2,014 research outputs found
P-Selectivity, Immunity, and the Power of One Bit
We prove that P-sel, the class of all P-selective sets, is EXP-immune, but is
not EXP/1-immune. That is, we prove that some infinite P-selective set has no
infinite EXP-time subset, but we also prove that every infinite P-selective set
has some infinite subset in EXP/1. Informally put, the immunity of P-sel is so
fragile that it is pierced by a single bit of information.
The above claims follow from broader results that we obtain about the
immunity of the P-selective sets. In particular, we prove that for every
recursive function f, P-sel is DTIME(f)-immune. Yet we also prove that P-sel is
not \Pi_2^p/1-immune
Wrinkling prediction in sheet metal forming and experimental verification
In this work, the analysis of Hutchinson and Neale is used for wrinkling prediction. Under a number of assumptions, limitations and simplifications a wrinkling criterion with some restrictive applicability, is obtained. Unfortunately, Hutchinson analysis is limited to regions of the sheet that are free of any contact. When contact is taken into account the problem is further complicated. Consequently, a local indicator based on the change of curvatures under compressive stresses is developed. Both wrinkling indicators are used to drive the adaptive mesh refinement in order to be able to accurately spot wrinkling. The numerical results will be compared to those obtained through experimental testing. A number of hemispherical product samples have been used with various blank holder forces and drawn to different depths to capture the onset of wrinkling, its mode and locatio
Behavior of heuristics and state space structure near SAT/UNSAT transition
We study the behavior of ASAT, a heuristic for solving satisfiability
problems by stochastic local search near the SAT/UNSAT transition. The
heuristic is focused, i.e. only variables in unsatisfied clauses are updated in
each step, and is significantly simpler, while similar to, walksat or Focused
Metropolis Search. We show that ASAT solves instances as large as one million
variables in linear time, on average, up to 4.21 clauses per variable for
random 3SAT. For K higher than 3, ASAT appears to solve instances at the ``FRSB
threshold'' in linear time, up to K=7.Comment: 12 pages, 6 figures, longer version available as MSc thesis of first
author at http://biophys.physics.kth.se/docs/ardelius_thesis.pd
RITUXIMAB DELAYS WOUND HEALING AND DECREASES WHITE BLOOD CELL COUNT IN MALE MICE
ABSTRACTObjective: The aims of this research are to evaluate the effect of rituximab on wound healing, some hematological parameters, histological changes inwound healing, and histopathological changes in some organs in male mice.Methods: Totally, 15 adult male mice (25-30 g) were enrolled in this study. Animals were kept in the animal house College of Medicine/Universityof Babylon, and the temperature was controlled on 25°C and 14 hrs light and 10 hrs dark cycles. The animals were provided with standard diet andwater ad libitum. The animals were divided randomly into 3 groups, five mice in each group, Group 1 (control group) received no treatment, Group 2received rituximab 1 m/kg, IP, at days 0, 5, and 10 after wounding, in Group 3, rituximab was topically applied to the wound at days 0, 5, and 10 afterwounding.Results: The results yield that the wound healing significantly decreased (p<0.05) in Groups 2 and 3 as compared to control group. While the resultsregarding white blood cells (WBCs) count, there is a significant decrease in WBC count in Group 2 (p>0.05). Platelets and red blood cell count insignificantly increased in Group 3 as compared to control group (p<0.05). There were no histopathological changes in the skin, kidneys, and spleen.In liver, nonsignificant histopathological changes (p>0.05) found in Group 2 and 3 as compared to control group.Conclusion: Rituximab delays wound healing and reduces WBC count in male mice.Keywords: Rituximab, Wound healing, Lymphocyte, CD20, White blood cells, Mice
Focused Local Search for Random 3-Satisfiability
A local search algorithm solving an NP-complete optimisation problem can be
viewed as a stochastic process moving in an 'energy landscape' towards
eventually finding an optimal solution. For the random 3-satisfiability
problem, the heuristic of focusing the local moves on the presently
unsatisfiedclauses is known to be very effective: the time to solution has been
observed to grow only linearly in the number of variables, for a given
clauses-to-variables ratio sufficiently far below the critical
satisfiability threshold . We present numerical results
on the behaviour of three focused local search algorithms for this problem,
considering in particular the characteristics of a focused variant of the
simple Metropolis dynamics. We estimate the optimal value for the
``temperature'' parameter for this algorithm, such that its linear-time
regime extends as close to as possible. Similar parameter
optimisation is performed also for the well-known WalkSAT algorithm and for the
less studied, but very well performing Focused Record-to-Record Travel method.
We observe that with an appropriate choice of parameters, the linear time
regime for each of these algorithms seems to extend well into ratios -- much further than has so far been generally assumed. We discuss the
statistics of solution times for the algorithms, relate their performance to
the process of ``whitening'', and present some conjectures on the shape of
their computational phase diagrams.Comment: 20 pages, lots of figure
Emisija kratkovalnog zračenja tijekom udara iona o čvrstu površinu
The possibility of short-wave photon emission during surface scattering of positive ions is investigated by selection of the type of charge-exchange process (one- or two-electron processes), through the calculation of the neutralization probabilities and the charge-transfer cross sections. These probabilities are calculated statically as a function of distance between the incident ion and the surface, and dynamically as a function of the ion velocity. The model is applied to real systems such as He+/semiconductor (silicon and germanium), taking into account the difference in the physical constants of the two systems. We found that emitted photons have short wavelengths, lying in the ultraviolet range of the electromagnetic spectrum of the helium emission spectrum.Istražujemo mogućnost emisije kratkovalnih fotona tijekom udara iona o čvrstu površinu odabirom procesa izmjene naboja (jedno i dvoelektronski procesi) i računanjem vjerojatnosti neutralizacije i udarnog presjeka za prijenos naboja. Te vjerojatnosti računamo statički kao funkcije udaljenosti upadnog iona i površine, i dinamički kao funkcije brzine iona. Model primjenjujemo stvarnim sustavima kao što su poluvodiči silicij i germanij, uzimajući u obzir razlike fizičkih svojstava dvaju sustava. Nalazimo da fotoni imaju kratke valne duljine, u području elektromagnetskog spektra helija
Massive Necrotizing Pancreatitis in an Immunosuppressed Renal Transplant Recipient (Successful Therapy)
Severe pancreatitis may be associated with massive necrosis of the pancreas and/or retroperitoneal
adipose tissue. Toxicity results from the dead tissue and secondary infection. A 45 year old patient,
while fully immunosuppressed, developed this complication following cadaveric renal transplantation.
He survived continued immunosuppression, 16 operative debridements of the retroperitoneum, and
maintained a functioning renal transplant
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