727 research outputs found
Avalanche frontiers in dissipative abelian sandpile model as off-critical SLE(2)
Avalanche frontiers in Abelian Sandpile Model (ASM) are random simple curves
whose continuum limit is known to be a Schramm-Loewner Evolution (SLE) with
diffusivity parameter . In this paper we consider the dissipative
ASM and study the statistics of the avalanche and wave frontiers for various
rates of dissipation. We examine the scaling behavior of a number of functions
such as the correlation length, the exponent of distribution function of loop
lengths and gyration radius defined for waves and avalanches. We find that they
do scale with the rate of dissipation. Two significant length scales are
observed. For length scales much smaller than the correlation length, these
curves show properties close to the critical curves and the corresponding
diffusivity parameter is nearly the same as the critical limit. We interpret
this as the ultra violet (UV) limit where corresponding to .
For length scales much larger than the correlation length we find that the
avalanche frontiers tend to Self-Avoiding Walk, the corresponding driving
function is proportional to the Brownian motion with the diffusion parameter
corresponding to a field theory with . This is the infra
red (IR) limit. Correspondingly the central charge decreases from the IR to the
UV point.Comment: 11 Pages, 6 Figure
Patterned and Disordered Continuous Abelian Sandpile Model
We study critical properties of the continuous Abelian sandpile model with
anisotropies in toppling rules that produce ordered patterns on it. Also we
consider the continuous directed sandpile model perturbed by a weak quenched
randomness and study critical behavior of the model using perturbative
conformal field theory and show the model has a new random fixed point.Comment: 11 Pages, 6 figure
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Lamina Cribrosa and Choroid Features and Their Relationship to Stage of Pseudoexfoliation Glaucoma.
PurposeTo better understand the relationship of lamina cribrosa (LC) and choroid features to the severity of pseudoexfoliation glaucoma (PXG).MethodsIn this cross-sectional study, 137 eyes of 122 subjects (47 eyes with moderate/advanced PXG [mean deviation (MD), -15.0 ± 7.7 dB], 34 eyes with mild PXG [MD, -2.7 ± 1.5 dB], 32 aged-matched pseudoexfoliation syndrome [PXS] eyes, and 24 aged-matched control eyes) were investigated. Optic discs, LC thickness, and anterior LC depth (ALD; midsuperior, center, and midinferior) as well as peripapillary choroidal thickness were determined. Linear mixed modeling was used to adjust for age, sex, and axial length.ResultsA progressive decrease in LC thickness was found when comparing controls (271.9 ± 61.3 μm), PXS (212.6 ± 51.5 μm), mild PXG (180.8 ± 24.6 μm), and moderate/advance PXG (138.9 ± 37.5 μm) (P < 0.001). ALD was greater (P < 0.001) in moderate/advance glaucoma (306.7 ± 105.3 μm) and mild PXG (209.5 ± 79.7 μm) compared with PXS (155 ± 86.7 μm) and healthy controls (149.2 ± 103 μm). Although eyes with moderate/advance PXG had the thinnest choroid (117.2 ± 36.6 μm), choroidal thickness was comparable in mild PXG, PXS, and controls (150.0 ± 46.1, 159.7 ± 65.5, and 157.5 ± 51.1 μm, respectively; P = 0.002). Worse MD was the only factor associated with thinner LC (β = 2.344, P < 0.001) and choroid (β = 1.717, P = 0.009 μm) in PXG eyes. Higher IOP (β = 4.305, P = 0.013) and worse MD (β = -6.390, P < 0.001) were associated with deeper ALD in PXG.ConclusionsIn pseudoexfoliation, LC thinning is an early sign, and there is progressive thinning with advancing glaucoma. Choroidal thinning is observable only with moderate/advanced glaucoma. In PXG eyes, LC thickness, depth, and peripapillary choroidal thickness are associated with glaucoma severity
Jordan derivations on certain Banach algebras
In this paper, we study the types of Jordan derivations of a Banach algebra
with a right identity . We show that if is commutative and
semisimple, then every Jordan derivation of is a derivation. In this
case, Jordan derivations map into the radical of . We also prove that
every Jordan triple left (right) derivation of is a Jordan left (right)
derivation. Finally, we investigate the range of Jordan left derivations and
establish that every Jordan left derivation of maps into
Spatial Asymmetric Two dimensional Continuous Abelian Sandpile Model
We insert some asymmetries in the continuous Abelian sandpile models, such as
directedness and ellipticity. We analyze probability distribution of different
heights and also find the field theory corresponding to the models. Also we
find the fields associated with some height variables.Comment: 14 Pages, 11 Figure
A Mathematical Model to Investigate Heat Transfer in Footwear during Walking and Jogging
Foot temperature during activities of daily living affects the human performance and well-being. Footwear thermal characteristics affect the foot temperature inside the shoe during activities of daily living. The temperate at the sole of the foot (plantar temperature) is influenced by different thermal properties such as heat capacity, heat diffusivity, and thermal conductivity of the shoe sole in addition to its mechanical properties. Hence the purpose of this study was to propose a method to allow investigating the effect of footwear thermal characteristics on the foot temperature during activities of daily living, like walking or jogging.
The transient heat transfer between the foot and the ground was studied to drive the governing equation for heat transfer modelling in footwear and to predict foot sole temperature during walking, and jogging. Different thermo-mechanical properties of shoe sole, as well as geometrical parameters, were investigated. The proposed model showed to be able to adequately predict the plantar temperature at the ball of the foot when compared to the results from experimental measurements. Finally, using the proposed method, the thermal behaviour of two different shoes with two different sole materials EVA08 and EVA12 were compared. It was shown that heat capacity as compared to the thermal conductivity of the shoe sole is more effective in reducing the plantar temperature increase in short term. The proposed method proved to be able to accurately predict the thermal behaviour of shoes and can provide a tool to predict footwear thermal comfort
Bacterial spectrum and antimicrobial resistance pattern in cancer patients with febrile neutropenia
Background: Bacterial bloodstream infections are one of the most common complications in cancer patients under treatment. Bacteremia in these patients is a medical crisis that needs antibiotic treatment. The aim of this study was to determine bacterial spectrum and antimicrobial resistance pattern in febrile neutropenic cancer patients. Methods: In this prospective study, 212 cancer patients with febrile neutropenia who were referred to Shahid Sadoughi hospital in Yazd from 2012 to 2015 were participated. Bacterial pathogens isolated by the BACTEC media and antimicrobial susceptibility tests performed according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: The mean age of patients was 43.5 ± 24.98 years old. Out of 212 participants, 62.3 (132/212) were suffering from hematologic malignancies, and 37.7 (80/212) had solid tumors. Gram-negative bacteria were the predominant microorganisms (84.9). E.coli was the most frequently isolated pathogen (38.68 ), followed by Klebsiella (14.15) and Acinetobacter species (11.32). In addition, Staphylococcus epidermidis was the most common isolated Gram-positive bacteria (8.5). Gram-negative bacteria were susceptible to ciprofloxacin with a response range of 53.7 to 100. The majority of E.coli isolates were sensitive to ceftazidime (87.8) and were resistance to Co-trimoxazole (15.8). Klebsiella isolates were 100 susceptible to cephalosporins, meropenem and imipenem. Conclusion: The majority of bacterial pathogens were resistance to various antibiotics. Judicious use of antibiotic therapy can prevent the emergence and spread of antibiotic-resistant Gram-negative bacteria. © 2019, Asian Pacific Journal of Cancer Prevention
Prevalence of high-risk human papillomavirus types among women screened for cervical cancer in yazd, iran, and comparison of cytology, histology, and colposcopy results
Background: Human Papillomavirus (HPV) is a DNA virus with more than 100 genotypes, at least 12 of which are high-risk and associated with high-grade cervical lesions. Data on the prevalence of high-risk HPV genotypes among women are not yet available for the total regions of Iran. Objectives: The present study aimed to determine the prevalence of high-risk HPV types among women screened for cervical carci-noma in Yazd and compare the cytology, histology, and colposcopy results. Methods: In this cross-sectional study, 402 women referring to gynecology clinics of Shahid Sadoughi University of Medical Sci-ences, Yazd, Iran, were selected. The Pap smear and HPV typing were performed on cervical samples. The high-risk HPV types were detected by the polymerase chain reaction (PCR)-based reverse blot hybridization assay. Colposcopy was carried out on patients with high-risk HPV types, and biopsies were taken for histological examination. Results: Among 402 women screened by HPV-PCR, 32 (7.97) women were positive for high-risk HPV types. Human papillomavirus 16 and HPV18 were the most frequent genotypes (46.9). The cytology, histology, and colposcopy results were abnormal in 56.2, 29.1, and 71.9 of patients, respectively. Pap smear had 100 sensitivity and 58.3 specificity for the detection of high-grade cervical lesions, while these values for colposcopy were 75 and 87.5, respectively. Conclusions: The frequency of high-risk HPV types was relatively low among women living in Yazd than in those from other provinces of Iran. A significant percentage of patients with HPV had normal cervical cytology and histology. Therefore, HPV typing is recommended to decrease the development of cervical cancer. Colposcopy had acceptable sensitivity and specificity for the detection of high-grade cervical lesions. © 2020, Author(s)
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