Increased cutaneous cells following warm water challenge in pruritus-related polycythemia vera (P... more Increased cutaneous cells following warm water challenge in pruritus-related polycythemia vera (PV) have been reported, but their nature and magnitude are not known. Qualitative and quantitative assessments (digital image analysis) of the cutaneous mononuclear cells, eosinophils and mast cells were carried out in PV patients and healthy controls (n = 10 each) following exposures to water at room temperature and warm water. Infiltration of the spongiotic epidermis and dermis by mononuclear cells and eosinophils together with edema and vasodilatation of upper dermis following warm water contact was clearly observed only in PV patients. In contrast to controls, significant increase in numbers of mononuclear cells and eosinophils in comparison with exposure to water at room temperature at the dermal-epidermal junction (p < 0.01), papillary dermis (p < 0.01) and perivascular area (p < 0.05) was found. Obvious mast cell degranulation was seen in PV sections after warm water contact, but no significant increase of their numbers was observed whether among PV patients or healthy controls (p > 0.05). However, the numbers of papillary dermal mast cells in specimens obtained from PV patients following room temperature water exposure were significantly more than those of healthy controls (p < 0.05). PV represents an invisible dermatosis in which the infiltrating mononuclear cells and eosinophils may have a role in warm water-induced pruritus.
2011 28th National Radio Science Conference (NRSC), 2011
In this paper, it was intended to investigate the possibility of generating a random chaotic sequ... more In this paper, it was intended to investigate the possibility of generating a random chaotic sequence, having a uniform histogram, using a chaotic sequence matching a given histogram and a chaotic sequence matching the complement of this histogram . To study the relation between these two sequences three methods are used to determine the complement of the histogram . Then based on the chaotic map tailoring synthesis method, the given histogram and a chosen starting point are used to generate the ftrst chaotic sequence of a length L. The same procedure is repeated with the complement histogram to generate the second chaotic sequence of same length L. Histograms are computed for each of the sequences. The two generated chaotic sequences are then combined through simple interleaving resulting in a third sequence of length 2L whose histogram is then determined. The process is repeated for the two methods used to determine the complement histogram. Unlike expected, the third sequence histogram is not a uniform one. In the third method ,t o obtain a sequence having uniform histogram, it is found necessary to combine, through simple concatenation, two relatively computed different lengths of ftrst and second chaotic sequences generated using original and complement histograms of the second or ftrst methods.
Digital signal classification using clustering has many applications in the civilian and military... more Digital signal classification using clustering has many applications in the civilian and military domains. Most of the proposed classifiers can only recognize a few types of digital signals. This paper presents a novel technique that deals with the classification of multi-user chirp modulation signals using clustering techniques. In this technique, a combination of higher order moments and cumulants are proposed as the effective features. Simulation results show that the proposed technique is able to classify the different types of chirp signals in additive white Gaussian noise (AWGN) channels and fuzzy c-means clustering (FCM) outperform fuzzy k-means clustering (FKM).
ABSTRACT In the context of cognitive radio or military applications, it is a crucial task to dist... more ABSTRACT In the context of cognitive radio or military applications, it is a crucial task to distinguish various OFDM based systems such as fixed WiMAX and Wi-Fi from each others. This paper presents a novel technique that deals with the classification of OFDM signals using higher order moments and cumulants with different types of classifiers and clustering techniques is proposed. Four classification techniques were considered, namely, Support Vector Machines, K-nearest neighbors, Maximum Likelihood and neural network (NN) classifiers. Two clustering techniques were utilized, namely, Fuzzy K-Means and Fuzzy C-means. Simulation results show that the proposed technique is able to classify different types of OFDM signals in Rayleigh fading and additive white Gaussian noise (AWGN) channels with high accuracy. It is also shown that the NN classifier outperforms the other three considered classifiers.
Thank you for choosing Leviton Network Solutions. Our copper, fiber, power, and Connected Home so... more Thank you for choosing Leviton Network Solutions. Our copper, fiber, power, and Connected Home solutions are ideal for today's most demanding applications, consistently exceeding our customers' expectations. Leviton CAT 6A structured cabling solutions are no exception. UTP eXtreme ® 6A channel-and component-rated performance options plus a shielded solution meet the needs of any application.
Good backoff algorithms should be able to achieve high channel throughput while maintaining fairn... more Good backoff algorithms should be able to achieve high channel throughput while maintaining fairness among active nodes. In this paper, we propose a novel backoff algorithm to improve the fairness of random access channels, while maximizing channel throughput. The ...
The pathophysiology of liver injury has attracted the interest of experimentalists and clinicians... more The pathophysiology of liver injury has attracted the interest of experimentalists and clinicians over many centuries. With the discovery of liver-specific pericytes -formerly called fat-storing cells, Ito-cells, lipocytes, and currently designated as hepatic stellate cells (HSC) -the insight into the cellular and molecular pathobiology of liver fibrosis has evolved and the pivotal role of HSC as a precursor cell-type for extracellular matrixproducing myofibroblasts has been established. Although activation and transdifferentiation of HSC to myofibroblasts is still regarded as the pathogenetic key mechanism of fibrogenesis, recent studies point to a prominent heterogeneity of the origin of myofibroblasts. Currently, the generation of matrix-synthesizing fibroblasts by epithelialmesenchymal transition, by influx of bone marrow-derived fibrocytes into damaged liver tissue, and by differentiation of circulating monocytes to fibroblasts after homing in the injured liver are discussed as important complementary mechanisms to enlarge the pool of (myo-)fibroblasts in the fibrosing liver. Among the molecular mediators, transforming growth factor-beta (TGF-b) plays a central role, which is controlled by the bonemorphogenetic protein (BMP)-7, an important antagonist of TGF-b action. The newly discovered pathways supplement the linear concept of HSC activation to myofibroblasts, point to fibrosis as a systemic response involving extrahepatic organs and reactions, add further evidence to a more or less uniform concept of organ fibrosis in general (e.g. liver, lung, kidney), and offer innovative approaches for the development of non-invasive biomarkers and antifibrotic trials.
European Journal of Gastroenterology & Hepatology, 2007
Liver cirrhosis is considered as a premalignant state, as about 80% of hepatocellular carcinoma (... more Liver cirrhosis is considered as a premalignant state, as about 80% of hepatocellular carcinoma (HCC) is associated with liver cirrhosis. Although alpha-fetoprotein (AFP) has a high negative predictive value, its sensitivity for detecting HCC is poor. The aim of this study was to evaluate circulating endoglin (CD105) in the serum of patients with liver cirrhosis and at high risk for HCC. CD105 and AFP serum concentrations were measured in 70 healthy and 94 nonliver-diseased controls and 130 patients with chronic liver diseases and HCC, respectively. Fifty-seven liver cirrhotic patients, 45 patients with liver cirrhosis plus HCC, 19 liver fibrosis patients and nine patients with HCC only were studied. Serum CD105 is significantly elevated in liver cirrhotic patients compared with healthy (P<0.0001) and nonliver-diseased controls (P<0.0001). Patients with liver cirrhosis and HCC show the highest CD105 concentrations being significantly elevated in comparison to liver cirrhosis (P=0.0006) and HCC only (P=0.0134). A stronger positive correlation exists between CD105 and AFP in the patient group suffering from liver cirrhosis and HCC (r=0.479, P=0.0015) than the obtained correlation between both markers in the group of patients diagnosed with liver cirrhosis alone (r=0.358, P=0.0073). The logistic regression model identified CD105 as an independent marker (P=0.0077, odds ratio 1.3). CD105 has the potential to be a novel complementary biomarker that has some important bearing on the risk assessment for development of HCC in cirrhotic patients.
The surface of 25 copper IUCDs and 25 inert IUCDs that had been in utero for less than 6 months o... more The surface of 25 copper IUCDs and 25 inert IUCDs that had been in utero for less than 6 months or more than a year was examined by the scanning electron microscope and the deposits were extracted from another 100 copper and inert IUCDs that had been in utero for less than 6 months or more than a year and examined by the atomic analyser. The most apparent changes were, respectively, amorphous deposits and cellular debris, crystalline deposits, cracks, duplex coating, distortion and corrosion. Duplex coating was found only on inert IUCDs, but corrosion was found on copper IUCDs. The duration of use of the IUCDs had marked effect on the type of the deposits. Bleeding with IUCDs was associated with a thick layer of amorphous deposits. The contraceptive effect of the IUCDs was found to depend on the reaction of the host to the applied IUCDs rather than the type of device. The surface deposits were found to contain mainly calcium, phosphorus and magnesium.
The purpose of this study was to compare the error rates in breast imaging reports generated with... more The purpose of this study was to compare the error rates in breast imaging reports generated with automated speech recognition (ASR) technology as opposed to conventional dictation transcription. Breast imaging reports reviewed from January 2009 to April 2010 during multidisciplinary tumor board meetings at two hospitals were scrutinized for minor and major errors. Of 615 reports obtained, 308 were generated with ASR and 307 with conventional dictation transcription. At least one major error was found in 23% of ASR reports, as opposed to 4% of conventional dictation transcription reports (p < 0.01). Major errors were more common in breast MRI reports (35% of ASR and 7% of conventional reports), the lowest error rates occurring in reports of interventional procedures (13% of ASR and 4% of conventional reports) and mammography reports (15% of ASR and no conventional reports) (p < 0.01). The error rates did not differ substantially between reports generated by staff radiologists and trainees or between reports generated by speakers who spoke English as their first language and those whose native language was not English. After adjustment for academic rank, native language, and imaging modality, reports generated with ASR were 8 times as likely as conventional dictation transcription reports to contain major errors (p < 0.01). Reports generated with ASR are associated with higher error rates than reports generated with conventional dictation transcription. The imaging modality used is a predictor of the occurrence of reporting errors. Conversely, native language and academic rank of the speaker do not have a significant influence on error rate.
Increased cutaneous cells following warm water challenge in pruritus-related polycythemia vera (P... more Increased cutaneous cells following warm water challenge in pruritus-related polycythemia vera (PV) have been reported, but their nature and magnitude are not known. Qualitative and quantitative assessments (digital image analysis) of the cutaneous mononuclear cells, eosinophils and mast cells were carried out in PV patients and healthy controls (n = 10 each) following exposures to water at room temperature and warm water. Infiltration of the spongiotic epidermis and dermis by mononuclear cells and eosinophils together with edema and vasodilatation of upper dermis following warm water contact was clearly observed only in PV patients. In contrast to controls, significant increase in numbers of mononuclear cells and eosinophils in comparison with exposure to water at room temperature at the dermal-epidermal junction (p < 0.01), papillary dermis (p < 0.01) and perivascular area (p < 0.05) was found. Obvious mast cell degranulation was seen in PV sections after warm water contact, but no significant increase of their numbers was observed whether among PV patients or healthy controls (p > 0.05). However, the numbers of papillary dermal mast cells in specimens obtained from PV patients following room temperature water exposure were significantly more than those of healthy controls (p < 0.05). PV represents an invisible dermatosis in which the infiltrating mononuclear cells and eosinophils may have a role in warm water-induced pruritus.
2011 28th National Radio Science Conference (NRSC), 2011
In this paper, it was intended to investigate the possibility of generating a random chaotic sequ... more In this paper, it was intended to investigate the possibility of generating a random chaotic sequence, having a uniform histogram, using a chaotic sequence matching a given histogram and a chaotic sequence matching the complement of this histogram . To study the relation between these two sequences three methods are used to determine the complement of the histogram . Then based on the chaotic map tailoring synthesis method, the given histogram and a chosen starting point are used to generate the ftrst chaotic sequence of a length L. The same procedure is repeated with the complement histogram to generate the second chaotic sequence of same length L. Histograms are computed for each of the sequences. The two generated chaotic sequences are then combined through simple interleaving resulting in a third sequence of length 2L whose histogram is then determined. The process is repeated for the two methods used to determine the complement histogram. Unlike expected, the third sequence histogram is not a uniform one. In the third method ,t o obtain a sequence having uniform histogram, it is found necessary to combine, through simple concatenation, two relatively computed different lengths of ftrst and second chaotic sequences generated using original and complement histograms of the second or ftrst methods.
Digital signal classification using clustering has many applications in the civilian and military... more Digital signal classification using clustering has many applications in the civilian and military domains. Most of the proposed classifiers can only recognize a few types of digital signals. This paper presents a novel technique that deals with the classification of multi-user chirp modulation signals using clustering techniques. In this technique, a combination of higher order moments and cumulants are proposed as the effective features. Simulation results show that the proposed technique is able to classify the different types of chirp signals in additive white Gaussian noise (AWGN) channels and fuzzy c-means clustering (FCM) outperform fuzzy k-means clustering (FKM).
ABSTRACT In the context of cognitive radio or military applications, it is a crucial task to dist... more ABSTRACT In the context of cognitive radio or military applications, it is a crucial task to distinguish various OFDM based systems such as fixed WiMAX and Wi-Fi from each others. This paper presents a novel technique that deals with the classification of OFDM signals using higher order moments and cumulants with different types of classifiers and clustering techniques is proposed. Four classification techniques were considered, namely, Support Vector Machines, K-nearest neighbors, Maximum Likelihood and neural network (NN) classifiers. Two clustering techniques were utilized, namely, Fuzzy K-Means and Fuzzy C-means. Simulation results show that the proposed technique is able to classify different types of OFDM signals in Rayleigh fading and additive white Gaussian noise (AWGN) channels with high accuracy. It is also shown that the NN classifier outperforms the other three considered classifiers.
Thank you for choosing Leviton Network Solutions. Our copper, fiber, power, and Connected Home so... more Thank you for choosing Leviton Network Solutions. Our copper, fiber, power, and Connected Home solutions are ideal for today's most demanding applications, consistently exceeding our customers' expectations. Leviton CAT 6A structured cabling solutions are no exception. UTP eXtreme ® 6A channel-and component-rated performance options plus a shielded solution meet the needs of any application.
Good backoff algorithms should be able to achieve high channel throughput while maintaining fairn... more Good backoff algorithms should be able to achieve high channel throughput while maintaining fairness among active nodes. In this paper, we propose a novel backoff algorithm to improve the fairness of random access channels, while maximizing channel throughput. The ...
The pathophysiology of liver injury has attracted the interest of experimentalists and clinicians... more The pathophysiology of liver injury has attracted the interest of experimentalists and clinicians over many centuries. With the discovery of liver-specific pericytes -formerly called fat-storing cells, Ito-cells, lipocytes, and currently designated as hepatic stellate cells (HSC) -the insight into the cellular and molecular pathobiology of liver fibrosis has evolved and the pivotal role of HSC as a precursor cell-type for extracellular matrixproducing myofibroblasts has been established. Although activation and transdifferentiation of HSC to myofibroblasts is still regarded as the pathogenetic key mechanism of fibrogenesis, recent studies point to a prominent heterogeneity of the origin of myofibroblasts. Currently, the generation of matrix-synthesizing fibroblasts by epithelialmesenchymal transition, by influx of bone marrow-derived fibrocytes into damaged liver tissue, and by differentiation of circulating monocytes to fibroblasts after homing in the injured liver are discussed as important complementary mechanisms to enlarge the pool of (myo-)fibroblasts in the fibrosing liver. Among the molecular mediators, transforming growth factor-beta (TGF-b) plays a central role, which is controlled by the bonemorphogenetic protein (BMP)-7, an important antagonist of TGF-b action. The newly discovered pathways supplement the linear concept of HSC activation to myofibroblasts, point to fibrosis as a systemic response involving extrahepatic organs and reactions, add further evidence to a more or less uniform concept of organ fibrosis in general (e.g. liver, lung, kidney), and offer innovative approaches for the development of non-invasive biomarkers and antifibrotic trials.
European Journal of Gastroenterology & Hepatology, 2007
Liver cirrhosis is considered as a premalignant state, as about 80% of hepatocellular carcinoma (... more Liver cirrhosis is considered as a premalignant state, as about 80% of hepatocellular carcinoma (HCC) is associated with liver cirrhosis. Although alpha-fetoprotein (AFP) has a high negative predictive value, its sensitivity for detecting HCC is poor. The aim of this study was to evaluate circulating endoglin (CD105) in the serum of patients with liver cirrhosis and at high risk for HCC. CD105 and AFP serum concentrations were measured in 70 healthy and 94 nonliver-diseased controls and 130 patients with chronic liver diseases and HCC, respectively. Fifty-seven liver cirrhotic patients, 45 patients with liver cirrhosis plus HCC, 19 liver fibrosis patients and nine patients with HCC only were studied. Serum CD105 is significantly elevated in liver cirrhotic patients compared with healthy (P<0.0001) and nonliver-diseased controls (P<0.0001). Patients with liver cirrhosis and HCC show the highest CD105 concentrations being significantly elevated in comparison to liver cirrhosis (P=0.0006) and HCC only (P=0.0134). A stronger positive correlation exists between CD105 and AFP in the patient group suffering from liver cirrhosis and HCC (r=0.479, P=0.0015) than the obtained correlation between both markers in the group of patients diagnosed with liver cirrhosis alone (r=0.358, P=0.0073). The logistic regression model identified CD105 as an independent marker (P=0.0077, odds ratio 1.3). CD105 has the potential to be a novel complementary biomarker that has some important bearing on the risk assessment for development of HCC in cirrhotic patients.
The surface of 25 copper IUCDs and 25 inert IUCDs that had been in utero for less than 6 months o... more The surface of 25 copper IUCDs and 25 inert IUCDs that had been in utero for less than 6 months or more than a year was examined by the scanning electron microscope and the deposits were extracted from another 100 copper and inert IUCDs that had been in utero for less than 6 months or more than a year and examined by the atomic analyser. The most apparent changes were, respectively, amorphous deposits and cellular debris, crystalline deposits, cracks, duplex coating, distortion and corrosion. Duplex coating was found only on inert IUCDs, but corrosion was found on copper IUCDs. The duration of use of the IUCDs had marked effect on the type of the deposits. Bleeding with IUCDs was associated with a thick layer of amorphous deposits. The contraceptive effect of the IUCDs was found to depend on the reaction of the host to the applied IUCDs rather than the type of device. The surface deposits were found to contain mainly calcium, phosphorus and magnesium.
The purpose of this study was to compare the error rates in breast imaging reports generated with... more The purpose of this study was to compare the error rates in breast imaging reports generated with automated speech recognition (ASR) technology as opposed to conventional dictation transcription. Breast imaging reports reviewed from January 2009 to April 2010 during multidisciplinary tumor board meetings at two hospitals were scrutinized for minor and major errors. Of 615 reports obtained, 308 were generated with ASR and 307 with conventional dictation transcription. At least one major error was found in 23% of ASR reports, as opposed to 4% of conventional dictation transcription reports (p < 0.01). Major errors were more common in breast MRI reports (35% of ASR and 7% of conventional reports), the lowest error rates occurring in reports of interventional procedures (13% of ASR and 4% of conventional reports) and mammography reports (15% of ASR and no conventional reports) (p < 0.01). The error rates did not differ substantially between reports generated by staff radiologists and trainees or between reports generated by speakers who spoke English as their first language and those whose native language was not English. After adjustment for academic rank, native language, and imaging modality, reports generated with ASR were 8 times as likely as conventional dictation transcription reports to contain major errors (p < 0.01). Reports generated with ASR are associated with higher error rates than reports generated with conventional dictation transcription. The imaging modality used is a predictor of the occurrence of reporting errors. Conversely, native language and academic rank of the speaker do not have a significant influence on error rate.
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Papers by Mohamed Rizk