332 research outputs found
Comparison of chemotherapy and hematopoietic stem cell transplantation pre and postterm DMFT scores: A preliminary study
Aims: Chemotherapy is frequently used as a conditioning regimen to destroy malignant marrow cells before transplantation. Xerostomia, dysphagia, altered taste perception, mucositis, soft‑tissue ulceration, and infection are common adverse oral effects of chemotherapy. The study was aimed to compare decayed, missing, filled teeth (DMFT) scores before and after hematopoietic stem cell transplantation (HSCT) and chemotherapy.Materials and Methods: Thirty‑six patients undergoing HSCT were included in the study. Apre‑HSCT dental treatment protocol was implemented that consisted of restoration of all active carious lesions, treatment of periodontal infections, and extraction of all teeth with advanced periodontal disease. Upon completion of dental treatment, the importance of rigorous and effective oral hygiene was reemphasized, and patients were recalled 6 months later. DMFT scores were calculated prior to the initiation of HSCT treatment and 6 months after transplantation.Statistical Analysis Used: Regression analysis was used to evaluate the effects of HSCT and chemotherapy on DMFT scores.Results: Wilcoxon T test showed a statistically significant difference in DMFT scores before and after HSCT (P < 0.001). Conclusions: DMFT scores were found to increase after chemotherapy and HSCT, suggesting that the risk of infection is higher among HSCT patients when compared to other individuals. The results emphasize the need for dental examinations as an integral part of examination and treatment planning for patients undergoing HSCT and chemotherapy.Key words: Chemotherapy, decayed missing filled teeth scores, hematopoietic stem cell transplantatio
Simulated Dynamical Weakening and Abelian Avalanches in Mean-Field Driven Threshold Models
Mean-field coupled lattice maps are used to approximate the physics of driven
threshold systems with long range interactions. However, they are incapable of
modeling specific features of the dynamic instability responsible for
generating avalanches. Here we present a method of simulating specific
frictional weakening effects in a mean field slider block model. This provides
a means of exploring dynamical effects previously inaccessible to discrete time
simulations. This formulation also results in Abelian avalanches, where rupture
propagation is independent of the failure sequence. The resulting event size
distribution is shown to be generated by the boundary crossings of a stochastic
process. This is applied to typical models to explain some commonly observed
features.Comment: 27 pages, 9 figure
Phase ordering and roughening on growing films
We study the interplay between surface roughening and phase separation during
the growth of binary films. Already in 1+1 dimension, we find a variety of
different scaling behaviors depending on how the two phenomena are coupled. In
the most interesting case, related to the advection of a passive scalar in a
velocity field, nontrivial scaling exponents are obtained in simulations.Comment: 4 pages latex, 6 figure
Passive Sliders on Growing Surfaces and (anti-)Advection in Burger's Flows
We study the fluctuations of particles sliding on a stochastically growing
surface. This problem can be mapped to motion of passive scalars in a randomly
stirred Burger's flow. Renormalization group studies, simulations, and scaling
arguments in one dimension, suggest a rich set of phenomena: If particles slide
with the avalanche of growth sites (advection with the fluid), they tend to
cluster and follow the surface dynamics. However, for particles sliding against
the avalanche (anti-advection), we find slower diffusion dynamics, and density
fluctuations with no simple relation to the underlying fluid, possibly with
continuously varying exponents.Comment: 4 pages revtex
Differential charging in SiO2/Si systems as determined by XPS
The Si2p binding and the SiKLL kinetic energy difference between the SiO2 layer and Si substrate is shown to be influence by application of external voltage bias to the sample holder due to the differential charging as was already reported earlier (Ulgut, B.; Suzer, S. J. Phys. Chem. B 2003, 107, 2939). The cause of this bias induced (physical)-shift is now proven to be mostly due to partial neutralization by the stray electrons within the vacuum system by (i) introducing additional stray electrons via a filament and following their influence on the measured binding energy as a function of the applied voltage, (ii) measuring and Auger parameter. It is also shown that citrate-capped gold nanoclusters deposited on the SiO2/Si system experience differential charging similar to that of the oxide layer rather than the silicon substrate
Enhanced thermal stability of eugenol by cyclodextrin inclusion complex encapsulated in electrospun polymeric nanofibers
Polyvinyl alcohol (PVA) nanofibers encapsulating eugenol (EG)/cyclodextrin (CD) inclusion complexes (IC) (EG/CD-IC) were produced via electrospinning technique in order to achieve high thermal stability and slow release of EG. In order to find out the most favorable CD type for the stabilization of EG, three types of native cyclodextrins (α-CD, β-CD, and γ-CD) were used for the formation of EG/CD-IC. In the case of PVA/EG/α-CD nanofibers, uncomplexed EG was detected indicating that α-CD is not a proper host for EG/CD-IC formation. However, for PVA/EG/β-CD-IC and PVA/EG/γ-CD-IC nanofibers, enhanced durability and high thermal stability for EG were achieved due to the inclusion complexation. The electrospun nanofibers encapsulating CD-IC of active compounds such as eugenol may be quite useful in the food industry due to the extremely large surface area of nanofibers along with specific functionality, enhanced thermal stability, and slow release of the active compounds by CD inclusion complexation. © 2013 American Chemical Society
Isolation, genotyping and antimicrobial susceptibility of pathogenic Escherichia coli serotypes in ready to eat foods
NO ABSTRACT AVAILABLEIn this study, pathogenic Escherichia coli serotypes (E. coli O157:H7, O26, O111) and their molecular proximity and antimicrobial susceptibility were investigated in RTE foods. A total of 240 samples; consist of 105 stuffed mussel, 56 meatless cig kofte, 54 Russian salad, 25 cheese halva, were analyzed. The conventional culture and serotyping methods for determination of the organisms were performed and further confirmation by PCR was carried out. Confirmed E. coli O157 isolates were genotyped by the enterobacterial repetitive intergenic consensus(ERIC)-PCR. Antibacterial susceptibility testing of the isolates was performed by disc diffusion method. E. coli was detected in 7 (2.9 %) of 240 samples, including 3 (5.5%) Russian salad, 3 (2.8%) stuffed mussel, 1 (4 %) cheese halva. Two isolates from Russian salad, 1 from stuffed mussel and 1 from cheese halva were identified as E. coli O157 . In addition, stuffed mussel isolate was found to carry stx1 ve hlyA genes whereas one Russian salad isolate carried the stx1 gene. E. coli isolates were found to be resistant to amoxycillin/clavulonic acid, gentamicin and ciprofloxacin, at the rate of 29%, 14% and 29 %, respectively. Only one (14 %) isolate from stuffed mussel was classified as multidrug resistant to three antimicrobials. Furthermore, the isolates, related to O157 and O157:H7, presented different ribotypes in this study. The results provide useful data for the development of public health policy concerning the potential presence of pathogenic antimicrobial resistant E. coli serotypes in RTE foods. Strict surveillance of RTE foods at retail points for emerging pathogens, their antimicrobial resistance patterns and the potential likelihood of cross-contamination is required
Isolation, genotyping and antimicrobial susceptibility of pathogenic Escherichia coli serotypes in ready to eat foods
NO ABSTRACT AVAILABLEIn this study, pathogenic Escherichia coli serotypes (E. coli O157:H7, O26, O111) and their molecular proximity and antimicrobial susceptibility were investigated in RTE foods. A total of 240 samples; consist of 105 stuffed mussel, 56 meatless cig kofte, 54 Russian salad, 25 cheese halva, were analyzed. The conventional culture and serotyping methods for determination of the organisms were performed and further confirmation by PCR was carried out. Confirmed E. coli O157 isolates were genotyped by the enterobacterial repetitive intergenic consensus(ERIC)-PCR. Antibacterial susceptibility testing of the isolates was performed by disc diffusion method. E. coli was detected in 7 (2.9 %) of 240 samples, including 3 (5.5%) Russian salad, 3 (2.8%) stuffed mussel, 1 (4 %) cheese halva. Two isolates from Russian salad, 1 from stuffed mussel and 1 from cheese halva were identified as E. coli O157 . In addition, stuffed mussel isolate was found to carry stx1 ve hlyA genes whereas one Russian salad isolate carried the stx1 gene. E. coli isolates were found to be resistant to amoxycillin/clavulonic acid, gentamicin and ciprofloxacin, at the rate of 29%, 14% and 29 %, respectively. Only one (14 %) isolate from stuffed mussel was classified as multidrug resistant to three antimicrobials. Furthermore, the isolates, related to O157 and O157:H7, presented different ribotypes in this study. The results provide useful data for the development of public health policy concerning the potential presence of pathogenic antimicrobial resistant E. coli serotypes in RTE foods. Strict surveillance of RTE foods at retail points for emerging pathogens, their antimicrobial resistance patterns and the potential likelihood of cross-contamination is required
Anomalous Height Fluctuation Width in Crossover from Random to Coherent Surface Growths
We study an anomalous behavior of the height fluctuation width in the
crossover from random to coherent growths of surface for a stochastic model. In
the model, random numbers are assigned on perimeter sites of surface,
representing pinning strengths of disordered media. At each time, surface is
advanced at the site having minimum pinning strength in a random subset of
system rather than having global minimum. The subset is composed of a randomly
selected site and its neighbors. The height fluctuation width
exhibits the non-monotonic behavior with and it has a
minimum at . It is found numerically that scales as
, and the height fluctuation width at that minimum,
, scales as in 1+1 dimensions. It is found that
the subset-size is the characteristic size of the crossover from
the random surface growth in the KPZ universality, to the coherent surface
growth in the directed percolation universality.Comment: 13 postscript file
Separation quality of a geometric ratchet
We consider an experimentally relevant model of a geometric ratchet in which
particles undergo drift and diffusive motion in a two-dimensional periodic
array of obstacles, and which is used for the continuous separation of
particles subject to different forces. The macroscopic drift velocity and
diffusion tensor are calculated by a Monte-Carlo simulation and by a
master-equation approach, using the correponding microscopic quantities and the
shape of the obstacles as input. We define a measure of separation quality and
investigate its dependence on the applied force and the shape of the obstacles
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