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1.
Sensors (Basel) ; 24(7)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38610483

ABSTRACT

Relative radiometric normalization (RRN) is a critical pre-processing step that enables accurate comparisons of multitemporal remote-sensing (RS) images through unsupervised change detection. Although existing RRN methods generally have promising results in most cases, their effectiveness depends on specific conditions, especially in scenarios with land cover/land use (LULC) in image pairs in different locations. These methods often overlook these complexities, potentially introducing biases to RRN results, mainly because of the use of spatially aligned pseudo-invariant features (PIFs) for modeling. To address this, we introduce a location-independent RRN (LIRRN) method in this study that can automatically identify non-spatially matched PIFs based on brightness characteristics. Additionally, as a fast and coregistration-free model, LIRRN complements keypoint-based RRN for more accurate results in applications where coregistration is crucial. The LIRRN process starts with segmenting reference and subject images into dark, gray, and bright zones using the multi-Otsu threshold technique. PIFs are then efficiently extracted from each zone using nearest-distance-based image content matching without any spatial constraints. These PIFs construct a linear model during subject-image calibration on a band-by-band basis. The performance evaluation involved tests on five registered/unregistered bitemporal satellite images, comparing results from three conventional methods: histogram matching (HM), blockwise KAZE, and keypoint-based RRN algorithms. Experimental results consistently demonstrated LIRRN's superior performance, particularly in handling unregistered datasets. LIRRN also exhibited faster execution times than blockwise KAZE and keypoint-based approaches while yielding results comparable to those of HM in estimating normalization coefficients. Combining LIRRN and keypoint-based RRN models resulted in even more accurate and reliable results, albeit with a slight lengthening of the computational time. To investigate and further develop LIRRN, its code, and some sample datasets are available at link in Data Availability Statement.

2.
Lang Speech ; : 238309231213580, 2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38156468

ABSTRACT

Persian polar questions are characterized by a rise-fall followed by a low F0 plateau and a final rise. A production experiment was designed which systematically manipulated question length and the position of stress in the nuclear accented word in the question. Results revealed that distances between tones can strongly affect their scaling and alignment in predictable manner. With respect to scaling, our data show that the postnuclear low F0 target is realized considerably higher in short questions in which tonal crowding is more acute. This scaling adjustment of the L affects the following H tone, such that the final H is realized higher in tonal space, relative to the other crowding contexts. The results for duration show that in short questions, syllable duration is significantly lengthened so that there is room for tonal targets to be realized. In addition, the alignment data in this study suggest that crowding contexts incrementally affect the temporal adjustment of tonal targets. In some circumstances, tonal crowding results in anticipatory retraction of tones, while in others it results in carry-over tonal displacement depending on the direction of the prosodic pressure. These results can best be explained in an auto-segmental approach to intonational phonology in which intonation contours are treated as strings of distinct high and low tones associated with specific elements in the segmental string.

3.
Foods ; 12(19)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37835212

ABSTRACT

This study shows the possibility of using gallic acid (GA) and/or methyl gallate (MG) accompanied by phosphatidylcholine (PC) instead of tert-butylhydoquinone (TBHQ) for frying purposes. The antioxidants and PC were added in the concentrations of 1.2 mM and 500-2000 mg/kg, respectively. Oxidative stability index (OSI) and the kinetics of change in conjugated dienes (LCD), carbonyls (LCO), and acid value (AV) were used to assess the antioxidative treatments. GA alone and GA/MG (50:50) plus PC at 2000 mg/kg yielded the same OSI as that of TBHQ (18.4 h). The latter was of the highest frying performance in preventing the formation of LCD (rn = 0.0517/h and tT = 10.6 h vs. rn = 0.0976/h and tT = 4.5 h for TBHQ), LCO (rn = 0.0411/h and tT = 12.7 h vs. rn = 0.15/h and tT = 4.3 h for TBHQ), and hydrolytic products (AVm = 37.8 vs. 24.0 for TBHQ); rn: normalized the maximum rate of LCD/LCO accumulation; tT: the time at which the rate of LCD/LCO accumulation is maximized; AVm: quantitative measure of hydrolytic stability.

4.
Risk Anal ; 43(10): 2082-2098, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36627823

ABSTRACT

The role played by information and communication technologies in today's businesses cannot be underestimated. While such technological advancements provide numerous advantages and opportunities, they are known to thread organizations with new challenges such as cyberattacks. This is particularly important for small and medium-sized enterprises (SMEs) that are deemed to be the least mature and highly vulnerable to cybersecurity risks. Thus, this research is set to assess the cyber risks in online retailing SMEs (e-tailing SMEs). Therefore, this article employs a sample of 124 small e-tailers in the United Kingdom and takes advantage of a multi-criteria decision analysis (MCDA) method. Indeed, we identified a total number of 28 identified cyber-oriented risks in five exhaustive themes of "security," "dependency," "employee," "strategic," and "legal" risks. Subsequently, an integrated approach using step-wise weight assessment ratio analysis (SWARA) and best-worst method (BWM) has been employed to develop a pathway of risk assessment. As such, the current study outlines a novel approach toward cybersecurity risk management for e-tailing SMEs and discusses its effectiveness and contributions to the cyber risk management literature.

5.
J Med Signals Sens ; 12(3): 202-218, 2022.
Article in English | MEDLINE | ID: mdl-36120402

ABSTRACT

Background: Due to imprecise/missing data used for parameterization of ordinary differential equations (ODEs), model parameters are uncertain. Uncertainty of parameters has hindered the application of ODEs that require accurate parameters. Methods: We extended an available ODE model of tumor-immune system interactions via fuzzy logic to illustrate the fuzzification procedure of an ODE model. The fuzzy ODE (FODE) model assigns a fuzzy number to the parameters, to capture parametric uncertainty. We used the FODE model to predict tumor and immune cell dynamics and to assess the efficacy of 5-fluorouracil (5-FU) chemotherapy. Result: FODE model investigates how parametric uncertainty affects the uncertainty band of cell dynamics in the presence and absence of 5-FU treatment. In silico experiments revealed that the frequent 5-FU injection created a beneficial tumor microenvironment that exerted detrimental effects on tumor cells by enhancing the infiltration of CD8+ T cells, and natural killer cells, and decreasing that of myeloid-derived suppressor cells. The global sensitivity analysis was proved model robustness against random perturbation to parameters. Conclusion: ODE models with fuzzy uncertain kinetic parameters cope with insufficient/imprecise experimental data in the field of mathematical oncology and can predict cell dynamics uncertainty band.

6.
Phys Eng Sci Med ; 44(1): 253-263, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33591540

ABSTRACT

Elastography as one of the non-invasive medical imaging techniques which can help determine the stiffness of organs and other structures is currently attracting more attention. An interesting imaging rate-independent technique which has been discussed in literature uses shear wave interference patterns (SWIP). In this method, two external continuous harmonic vibration sources were used to induced SWIP and the resulting tissue displacements are mapped using ultrasonic imaging called sonoelastography. In this paper, a finite element model (FEM) of viscoelastic soft tissue with circular stiffer lesion inside, is simulated for testing the effect of stimulation characteristics on the propagation of SWIPs and shear speed map reconstruction. Also, we proposed an elastography probe, including miniature vibration sources and ultrasound transducer, which can be appropriate for experimental tests. The elastographic average speed ratio (ASR) and some scores like Dice coefficient, related to the binary image of shear speed map, are calculated for quantitatively measuring the effect of different contributing harmonic vibration parameters. Results show that the potential of providing useful diagnostic information can be improved if the preferable parameters are considered for implementation. According to these results the ASR, Dice and Jaccard scores would diverge from the ground truth of FEA if the parameter level is not selected correctly. Particularly, the Dice and Jaccard coefficients are obtained about 0.9 and 0.8, respectively, for the best vibration parameters level choice.


Subject(s)
Elasticity Imaging Techniques , Finite Element Analysis , Phantoms, Imaging , Ultrasonography , Vibration
7.
Trans R Soc Trop Med Hyg ; 114(10): 770-781, 2020 10 05.
Article in English | MEDLINE | ID: mdl-32609840

ABSTRACT

BACKGROUND: Quinolones are broad-spectrum antibiotics, which are used for the treatment of different infectious diseases associated with Enterobacteriaceae. During recent decades, the wide use as well as overuse of quinolones against diverse infections has led to the emergence of quinolone-resistant bacterial strains. Herein, we present the development of quinolone antibiotics, their function and also the different quinolone resistance mechanisms in Enterobacteriaceae by reviewing recent literature. METHODS: All data were extracted from Google Scholar search engine and PubMed site, using keywords; quinolone resistance, Enterobacteriaceae, plasmid-mediated quinolone resistance, etc. RESULTS AND CONCLUSION: The acquisition of resistance to quinolones is a complex and multifactorial process. The main resistance mechanisms consist of one or a combination of target-site gene mutations altering the drug-binding affinity of target enzymes. Other mechanisms of quinolone resistance are overexpression of AcrAB-tolC multidrug-resistant efflux pumps and downexpression of porins as well as plasmid-encoded resistance proteins including Qnr protection proteins, aminoglycoside acetyltransferase (AAC(6')-Ib-cr) and plasmid-encoded active efflux pumps such as OqxAB and QepA. The elucidation of resistance mechanisms will help researchers to explore new drugs against the resistant strains.


Subject(s)
Enterobacteriaceae Infections/drug therapy , Enterobacteriaceae/drug effects , Plasmids/genetics , Porins/genetics , Quinolones/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacterial Proteins/genetics , Drug Resistance, Bacterial/drug effects , Drug Resistance, Bacterial/genetics , Enterobacteriaceae/genetics , Enterobacteriaceae/isolation & purification , Humans , Microbial Sensitivity Tests , Plasmids/drug effects , Porins/drug effects , Quinolones/therapeutic use
8.
J Glob Antimicrob Resist ; 17: 39-43, 2019 06.
Article in English | MEDLINE | ID: mdl-30445211

ABSTRACT

OBJECTIVES: This study assessed genetic alterations in gyrA, gyrB, parC and parE and the prevalence of plasmid-mediated quinolone resistance (PMQR) genes among Escherichia coli and Klebsiella pneumoniae isolates from urinary tract infections (UTIs) in Azerbaijan, Iran. METHODS: A total of 205 clinical isolates of E. coli (n=177) and K. pneumoniae (n=28) were obtained from UTIs. Antimicrobial susceptibility was determined by disk diffusion and agar dilution assays. The presence of PMQR genes was determined by PCR, and sequencing of the gyrA, gyrB, parC and parE was performed. RESULTS: The rate of fluoroquinolone (FQ) resistance among the isolates was 77.1%. The Ser83Leu mutation in gyrA was observed in all 60 FQ-resistant isolates selected for direct sequencing. The second most common mutation in gyrA was Asp87Asn. Frequent mutations in parC were Ser80Ile and Glu84Val. Ser359Ala+Ser367Thr and Gly385Cys mutations in gyrB were identified in one isolate each of K. pneumoniae and E. coli, respectively. The parE gene had mutations at Ile529Leu, Ser458Ala and Leu416Phe. Overall, PMQR determinants were identified in 90% of E. coli and 100% of K. pneumoniae. The prevalence of PMQR genes was as follows: aac(6')-Ib-cr, 71.7%; oqxB, 51.7%; oqxA, 36.7%; qnrB, 28.3%; qnrS, 21.7%; qnrD, 16.7%; qepA, 5.0%; qnrA, 1.7%; and qnrC, 1.7%. CONCLUSIONS: FQ resistance rates were high. Mutations in DNA gyrase and topoisomerase IV and the prevalence of PMQR genes in E. coli and K. pneumoniae isolates were alarming. Moreover, the combination of these resistance mechanisms plays an important role in high-level FQ resistance.


Subject(s)
DNA Gyrase/genetics , DNA Topoisomerase IV/genetics , Drug Resistance, Bacterial , Escherichia coli/genetics , Klebsiella pneumoniae/genetics , Plasmids/genetics , Quinolones/pharmacology , Urinary Tract Infections/microbiology , Adult , Aged , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , DNA Gyrase/metabolism , DNA Topoisomerase IV/metabolism , Escherichia coli/drug effects , Escherichia coli/enzymology , Female , Humans , Iran , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/enzymology , Male , Microbial Sensitivity Tests , Middle Aged , Mutation , Plasmids/metabolism
9.
Cont Lens Anterior Eye ; 41(6): 489-495, 2018 12.
Article in English | MEDLINE | ID: mdl-30029924

ABSTRACT

PURPOSE: To introduce a method for estimation of the rigid gas-permeable contact lens (RGP) movement. MATERIALS AND METHODS: Videos captured from normal blinking of keratoconus patients while wearing RGP lenses were used for this study. The videos are recorded using the CCD camera of a smart phone attached to the eyepiece of the slit lamp. The algorithm starts with extracting two frames of the video related to the highest and lowest positions of the lens during blinking, followed by an appropriate edge detection method. In the next step circular Hough transform is used to find the center of lens and to segment it in each image. Finally the lens movement is estimated by measuring vertical displacement of the lens center between these two frames. RESULTS: Mean and standard deviation of the difference between real movement and results of the algorithm for 20 cases are -8.66% and 10.71% respectively. The results are highly correlated with Pearson coefficient 0.986 P < 0.001. Bland-Altman plot with 95% levels of agreement (LoA) shows an agreement between exact manual measurement method and the proposed algorithm. CONCLUSION: The proposed algorithm shows a relatively high accuracy as the first attempt and compared to the routine qualitative visual estimation. Considering the importance of the lens movement, although this system was not tested on a series of RGP fitting patients yet, semi-automatic measurement may potentially help practitioners decide the appropriate RGP lens fit and reduce the fitting time.


Subject(s)
Blinking , Contact Lenses , Image Processing, Computer-Assisted/methods , Keratoconus/therapy , Prosthesis Fitting/methods , Visual Acuity , Cornea/pathology , Corneal Topography/methods , Female , Humans , Keratoconus/diagnosis , Male , Reproducibility of Results , Retrospective Studies , Video Recording
10.
Lang Speech ; 60(4): 571-596, 2017 12.
Article in English | MEDLINE | ID: mdl-28112017

ABSTRACT

Previous literature on the phonetics of stress in Persian has reported that fundamental frequency is the only reliable acoustic correlate of stress, and that stressed and unstressed syllables are not differentiated from each other in the absence of accentuation. In this study, the effects of lexical stress on duration, overall intensity and spectral tilt were examined in Persian both in the accented and unaccented conditions. Results showed that syllable duration is consistently affected by stress in Persian in both the accented and unaccented conditions across all vowel types. Unlike duration, the results for overall intensity and spectral tilt were significant only in the accented condition, suggesting that measures of intensity are not a correlate of stress in Persian but they are mainly caused by the presence of a pitch movement. The findings are phonologically interpreted as suggesting that word-level prominence in Persian is typologically similar to 'stress accent' languages, in which multiple phonetic cues are used to signal the prominence contrast in the accented condition, and stressed and unstressed syllables are different from each other even when the word is not pitch-accented.


Subject(s)
Phonetics , Speech Acoustics , Voice Quality , Acoustics , Adult , Female , Humans , Iran , Male , Sound Spectrography , Speech Production Measurement , Time Factors , Young Adult
11.
Iran J Pediatr ; 23(2): 183-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23724180

ABSTRACT

OBJECTIVE: The aim of this study was to compare the Persian version of the wechsler intelligence scale for children - fourth edition (WISC-IV) and cognitive assessment system (CAS) tests, to determine the correlation between their scales and to evaluate the probable concurrent validity of these tests in patients with learning disorders. METHODS: One-hundered-sixty-two children with learning disorder who were presented at Atieh Comprehensive Psychiatry Center were selected in a consecutive non-randomized order. All of the patients were assessed based on WISC-IV and CAS scores questionnaires. Pearson correlation coefficient was used to analyze the correlation between the data and to assess the concurrent validity of the two tests. Linear regression was used for statistical modeling. The type one error was considered 5% in maximum. FINDINGS: There was a strong correlation between total score of WISC-IV test and total score of CAS test in the patients (r=0.75, P<0.001). The correlations among the other scales were mostly high and all of them were statistically significant (P<0.001). A linear regression model was obtained (α = 0.51, ß = 0.81 and P<0.001). CONCLUSION: There is an acceptable correlation between the WISC-IV scales and CAS test in children with learning disorders. A concurrent validity is established between the two tests and their scales.

12.
Neurosci Lett ; 516(1): 156-60, 2012 May 10.
Article in English | MEDLINE | ID: mdl-22503723

ABSTRACT

Neurofeedback training is increasingly used for ADHD treatment. However some ADHD patients are not treated through the long-time neurofeedback trainings with common protocols. In this paper a new graph theoretical approach is presented for EEG-based prediction of ADHD patients' responses to a common neurofeedback training: rewarding SMR activity (12-15 Hz) with inhibiting theta activity (4-8 Hz) and beta2 activity (18-25 Hz). Eyes closed EEGs of two groups before and after neurofeedback training were studied: ADHD patients with (15 children) and without (15 children) positive response to neurofeedback training. Employing a recent method to measure synchronization, fuzzy synchronization likelihood, functional connectivity graphs of the patients' brains were constructed in the full-band EEGs and 6 common EEG sub-bands produced by wavelet decomposition. Then, efficiencies of the brain networks in synchronizability and high speed information transmission were computed based on mean path length of the graphs, before and after neurofeedback training. The results were analyzed by ANOVA and showed synchronizability of the neocortex activity network at beta band in ADHDs with positive response is obviously less than that of ADHDs resistant to neurofeedback therapy, before treatment. The accuracy of linear discriminant analysis (LDA) in distinguishing these patients based on this feature is so high (84.2%) that this feature can be considered as reliable characteristics for prediction of responses of ADHDs to the neurofeedback trainings. Also difference between flexibility of the neocortex in beta band before and after treatment is obviously larger in the ADHDs with positive response in comparison to those with negative response which may be a neurophysiologic reason for dissatisfaction of the last group to the neurofeedback therapy.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Attention Deficit Disorder with Hyperactivity/therapy , Biofeedback, Psychology/methods , Models, Neurological , Neocortex/physiopathology , Nerve Net/physiopathology , Therapy, Computer-Assisted/methods , Adolescent , Child , Computer Simulation , Female , Humans , Male
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