Mohamed Medhat

Followers

Following

Public Views

Interests

Uploads

Papers by Mohamed Medhat

The COVEG score to predict severity and mortality among hospitalized patients with COVID-19

Journal of Infection in Developing Countries, Jul 28, 2022

Introduction: COVID-19 severity and mortality predictors could determine admission criteria and r... more Introduction: COVID-19 severity and mortality predictors could determine admission criteria and reduce mortality. We aimed to evaluate the clinical-laboratory features of hospitalized patients with COVID-19 to develop a novel score of severity and mortality. Methodology: This retrospective cohort study was conducted using data from patients with COVID-19 who were admitted to five Egyptian university hospitals. Demographics, comorbidities, clinical manifestations, laboratory parameters, the duration of hospitalization, and disease outcome were analyzed, and a score to predict severity and mortality was developed. Results: A total of 1308 patients with COVID-19, with 996 (76.1%) being moderate and 312 (23.9%) being severe cases, were included. The mean age was 46.5 ± 17.1 years, and 61.6% were males. The overall mortality was 12.6%. Regression analysis determined significant predictors, and a ROC curve defined cutoff values. The COVEG severity score was defined by age ≥ 54, D-dimer ≥ 0.795, serum ferritin ≥ 406, C-reactive protein ≥ 30.1, and neutrophil: lymphocyte ratio ≥ 2.88. The COVEG mortality score was based on COVEG severity and the presence of cardiac diseases. Both COVEG scores had high predictive values (area under the curve 0.882 and 0.883, respectively). Conclusions: COVEG score predicts the severity and mortality of patients with COVID-19 accurately.

Download

Distance Measurement using Opto-Electronic Oscillators

Conference on Lasers and Electro-Optics

Precise distance measurement plays an important role in surveying, construction and advanced engi... more

Design of IR zoom lens system for long-range detection in uncooled LWIR camera

Journal of Optics

A new compact optical zoom lens system with variable focal length 100–200 mm for uncooled LWIR (8... more A new compact optical zoom lens system with variable focal length 100–200 mm for uncooled LWIR (8–12 μm) camera is designed. It is used for long-range detection. The optimized IR zoom lens consists of four group elements. The F/# of the zoom system is F/1.4 at all zoom positions. Its performance reaches the diffraction limit at each focal length position. Moreover, optical design and image quality are calculated by ZEMAX optical software. The imaging quality performance is steady during zoom process. In addition to the above benefits, the optimized IR zoom lens is light and compact (200 mm) with 4 lenses and only one of them has diffractive surface to lower production cost. Upon applying anti-reflection coating, the total transmittance of the optical system is enhanced from 2 to 99% at λ = 10 µm.

Download

Sofosbuvir/ledipasvir in combination or nitazoxanide alone are safe and efficient treatments for COVID-19 infection: A randomized controlled trial for repurposing antivirals

Arab Journal of Gastroenterology

Ulcerative colitis as a possible sequela of COVID-19 Infection: The endless story

Arab Journal of Gastroenterology

The coronavirus disease 2019 (COVID-19), caused by the novel coronavirus SARS-CoV-2, is a new typ... more The coronavirus disease 2019 (COVID-19), caused by the novel coronavirus SARS-CoV-2, is a new type of acute infectious respiratory syndrome that usually presents with mild flu-like symptoms. However, the disease caused widespread illness and death worldwide, and new sequelae are still being discovered. SARS-CoV-2 RNA was isolated from the fecal samples of some infected patients. Many pathogens, including many viral infections, were linked either to the onset or the exacerbation of inflammatory bowel disease (IBD). With this, we report a series of 2 IBD cases that were diagnosed shortly after recovery from COVID-19. This is the first report that discusses the possibility of developing IBD following COVID-19 infection to the best of our knowledge. This could highlight the importance of thoroughly investigating COVID-19 patients who presented with diarrhea, particularly those with bloody diarrhea, and not consider it a simple manifestation of COVID-19 infection.

Islam and Otherness | PLURIEL 3rd International Congress

The PLURIEL network aims to promote the link between researchers on Islam and the Muslim-Christia... more The PLURIEL network aims to promote the link between researchers on Islam and the Muslim-Christian dialogue, in connection with Eastern Christians, and to foster the interaction between academics, social actors and economic organisations. The network gathers 150 researchers and 15 thematic groups. Its 3rd Congress will take place in Beirut, Lebanon from 14th to 17th April 2020. Congress website : https://evenement.pluriel.fuce.eu/ English THEME : ISLAM AND OTHERNESS True acceptance of otherness in a globalized and pluralistic world allows us to measure the capacity of religious, philosophical or political thought to fit in and assume the contemporary societal dynamics inherent to globalization (Taylor). This acceptance is not devoid of resistance that stem from the rise of entrenched identity expressions founded in particular on a vision of equality that is based on the &quot;similar&quot; which assumes a historical-ethnic [1] or religious identity. At the same time, the philosophy of interculturality and the policies of multiculturalism consider and support pluralism and multiculturalism (Fornet-Betencourt, Parekh, Taylor, Kymlicka, Tully). These lead to the reassessment of minority cultures, the rewriting of the history of solidarity, and the re-examination of the relationship between the center and the periphery within a national territory and in international relations. The 3rd International Congress of PLURIEL &quot;Islam and Otherness&quot; aims to address this societal movement from the perspective of Islam and beyond identity-based resistance. It will thus focus on how Islam can be considered a &#39;resource&#39; (Jullien) in order to approach the other in the globalized world. In this context, what is the other&#39;s specific thought that is being expressed to ground and support the dynamics of postmodernity? How is the other presented and brought together within contemporary Muslim movements and the policies of Muslim states to think differently about the legal evolution of personal status and equal civil rights? What thought-provoking strategies are being implemented to go beyond the classical frameworks established as orthodox principles, which are still maintained today to approach the dialogical relationship with the other? How does the rise of an inclusive or pluralistic Islamic thought lead non-Muslim theologians to renew their view of the Islamic reality, particularly with regard to Jews, Christians and atheists? Three approaches will make it possible to address the reality of otherness in Islam in terms of resources : Geopolitical, Dialogal, and Citizenship. [1] Pierre Rosanvallon, La Société des égaux, Paris, Seuil, 2011. Français THEME : ISLAM ET ALTÉRiTÉ Dans un monde globalisé et pluraliste, la reconnaissance de l’altérité permet de mesurer la capacité d’une pensée religieuse, philosophique ou politique à intégrer les dynamiques sociétales contemporaines inhérentes à la mondialisation (Taylor). Or l’acceptation de l’autre ne va pas sans susciter des résistances et réveiller des réactions identitaires fermées qui se réclament d’une vision où l’égalité est réservée au semblable et qui présuppose une identité religieuse ou historico-ethnique (Rosanvallon) [1]. C’est dans ce contexte que la philosophie de l’interculturalité et les politiques du multiculturalisme pensent le pluralisme et accompagnent le multiculturalisme (Fornet-Betencourt, Parekh, Taylor, Kymlicka, Tully). Elles conduisent à revaloriser les cultures minoritaires, à réécrire l’histoire des solidarités, à repenser le rapport centre / périphérie au sein d’un territoire national et au niveau des relations internationales. Le Congrès « Islam et altérité » propose de réfléchir sur la manière dont l’islam s’insère dans ce mouvement sociétal au-delà des résistances identitaires. Il s’agira ainsi de se demander comment l’islam se présente lui-même comme une « ressource » (Jullien) pour penser l’autre dans ce monde globalisé ? Quelle pensée spécifique de l’autre offre-t-il pour fonder les dynamiques de la postmodernité ? Comment l’autre est-il présenté au sein des mouvements musulmans contemporains et quel rôle lui est-il assigné dans les politiques des États musulmans en vue de faire évoluer le statut personnel et l’égalité des droits civiques ? Quelles stratégies réflexives sont mises en œuvre pour dépasser les cadres classiques toujours en applications ? Enfin, comment l’essor d’une pensée islamique inclusiviste ou pluraliste conduit à renouveler le regard qu’il porte sur la réalité islamique à l’égard notamment des juifs, chrétiens et athées ? Trois axes permettront d’approcher la réalité de l’altérité en islam en termes de ressources : axe géopolitique, axe dialogal et axe citoyenneté (muwatana). [1] Pierre Rosanvallon, La Société des égaux, Paris, Seuil, 2011.

$Research paper thumbnail of Kretschmann-Based Optical Sensor via Thermally Tunable Refractive Index$

Kretschmann-Based Optical Sensor via Thermally Tunable Refractive Index

Crystals, 2021

This study discusses whether the prism used in a Kretschmann-based surface plasmon sensor can be ... more This study discusses whether the prism used in a Kretschmann-based surface plasmon sensor can be fabricated from a thermotropic liquid crystal (TLC) material. The refractive index of the TLC prism can be thermally tuned to match the excitation requirements for the surface plasmon modes along the metal–TLC interface of the proposed sensing platform. The TLC material was chemically prepared in vitro and was thermally and optically characterized. The measurements reported a wide mesophase temperature range ΔT (~35 °C) and a relatively high clearing temperature TC (~84 °C) which constitutes a stable thermal control for the TLC optical parameters. The experimentally measured refractive indices of the TLC material reflect a linear change in line with the temperatures at several selected wavelengths in the visible region. A design of the surface plasmon sensor was proposed, which provided a linear response to the investigated analytes refractive index. This work highlights the importance o...

Download

Using femtosecond laser pulses for electronic distance meter calibration

Applied Optics, 2020

Electronic distance meters (EDMs) are widely used in different applications, such as surveying an... more Electronic distance meters (EDMs) are widely used in different applications, such as surveying and civil engineering. In order to calibrate an EDM, different techniques can be used, including displacement interferometers and reference baselines. In this paper, an indoor baseline is designed and then accurately measured using femtosecond laser pulses from an optical frequency comb to be used for EDM calibration. The baseline consists of 13 fixed bases that cover 58 m distance. In order to accurately measure the distances between the bases, autocorrelation between femtosecond laser pulses is employed. The measurement shows a maximum precision of 14 µm over the 13 bases. Although this deviation is dominated mainly by the placement of the target mirror, the system capability is much more sufficient to safely calibrate the best available commercial EDM. The stability of the baseline is also investigated by measuring the interbase distances over long periods of time.

Workshop co-located with AI-2013 Thirty-third SGAI International Conference on Artificial Intelligence (BCS SGAI)

General knowledge sentiment lexicons have the advantage of wider term coverage. However, such lex... more General knowledge sentiment lexicons have the advantage of wider term coverage. However, such lexicons typically have inferior performance for sentiment classification compared to using domain focused lexicons or machine learning classifiers. Such poor performance can be attributed to the fact that some domain-specific sentiment-bearing terms may not be available from a general knowledge lexicon. Similarly, there is difference in usage of the same term between domain and general knowledge lexicons in some cases. In this paper, we propose a technique that uses distant-supervision to learn a domain focused sentiment lexicon. The technique further combines general knowledge lexicon with the domain focused lexicon for sentiment analysis. Implementation and evaluation of the technique on Twitter text show that sentiment analysis benefits from the combination of the two knowledge sources. The technique also performs better than state-of-the-art machine learning classifiers trained with distantsupervision dataset.

Download

DAAs treatment is associated with up-regulation of CD81 on peripheral B-lymphocytes

Access Microbiology, 2020

Cellular surface expression of CD81 (an essential co-receptor for HCV) is critical for successful... more Cellular surface expression of CD81 (an essential co-receptor for HCV) is critical for successful HCV infection. Furthermore, CD81 cross-linking with HCV-E2 protein impedes activation signaling pathways in different lymphocytes (T-cells, B -cells and NK cells). The expression of CD81 on peripheral lymphocytes is known to be downregulated following successful dual anti-HCV therapy. On the other hands, no reports are yet available regarding its expression levels following the newly used treatment regimen in Egypt; direct-acting antivirals (DAAs): Sofosubvir & daclatsvir for three months. Thus, the aim of the current study was to evaluate the expression levels of CD81 on T and B lymphocytes in HCV-infected patients before and after successful treatment with DAAs. Cellular CD81 expression was measured on CD3+ (T lymphocytes) and CD19+ (B Lymphocytes) lymphocytes by flow cytometry from 19 patients with chronic HCV infection. All the HCV viruses were of genotype 4. We found no correlation...

Collinear versus non-collinear autocorrelation between femtosecond pulses for absolute distance measurement

Measurement, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Download

Polyvinyl chloride/ styrene butadiene rubber polymeric blend filled with bismuth subcarbonate (BiO) 2 CO 3 as a shielding material for gamma rays

Polymer Composites, 2019

The polymer blend polyvinyl chloride/styrene-butadiene rubber filled of (BiO) 2 CO 3 with differe... more The polymer blend polyvinyl chloride/styrene-butadiene rubber filled of (BiO) 2 CO 3 with different concentrations (20, 30, 40, and 60 phr) were prepared by roll mill technique. The gamma-rays attenuation properties were carried out using NaI (Tl) gamma ray spectrometer using 232 Th. The attenuation coefficients, half value layer and mean free path were evaluated. The distribution of the filler within the polymer matrix was studied using scanning electron microscopy. The prepared polymer composites were characterized by X-ray diffraction technique to recognize the structural phase of the composites. The hardness and tensile strength of the composites were tested. The tensile strength of the composites was found to be

Download

Supervised learning algorithms for spacecraft attitude determination and control system health monitoring

IEEE Aerospace and Electronic Systems Magazine, 2017

Download

Context-aware adaptive data stream mining

Intelligent Data Analysis, 2009

Adsorption of phenol onto aluminium oxide and zinc oxide: A comparative study with titanium dioxide

Separation Science and Technology, 2018

This study conducted an investigation of aluminium oxide's and zinc oxide's ability to remove phe... more This study conducted an investigation of aluminium oxide's and zinc oxide's ability to remove phenol from wastewater through adsorption, and compare of their performance with titanium dioxide. The points of zero charge for the adsorbents were determined. The highest removal efficiencies for aluminium oxide, zinc oxide, and titanium dioxide were 14.7%, 12.2% and 33.5%, respectively. Equilibrium studies demonstrated the possibility of Frendluich isotherm, Temkin isotherm, and Dubinin-Radushkevich isotherm respectively expressing the adsorption isotherms for aluminium oxide, zinc oxide, and titanium dioxide. FTIR and SEM were used in conducting investigation on adsorbents. Among the three adsorbents, titanium dioxide was the best.

Download

Aktuelle Aspekte venerischer und genitaler Kontakinfektionen in Gynäkologie und Geburtshilfe

Gynäkologisch-geburtshilfliche Rundschau, 1985

Evaluation of moto-stand a new vehicle for upright ambulation in paraplegics

Spinal Cord, 1985

The Moto-Stand is a motorised vehicle to propel paraplegics in the upright position. It safely al... more The Moto-Stand is a motorised vehicle to propel paraplegics in the upright position. It safely allows handicapped persons a wide range of working capabilities and extends mobility far beyond the limits of a wheelchair. Twenty adults with spinal lesions were evaluated for using the Moto-Stand. The levels of lesion ranged from C6 to L ! . The tetraplegics studied had incomplete lesions and they could get on the Moto Stand but needed some assistance. All the paraplegics studied were able to use the Moto-Stand independently. The Moto-Stand was found to be superior for kitchen activities, especially when handling hot objects and reaching objects at different levels. As it turns in its own space it offers superior manoeuverability in the limited space of a kitchen, workshop or even a trailer home. Subjects with moderate to severe spasticity appear to have difficulty in using the Moto-Stand. It was found to be safe and comfortable by the majority of subjects studied.

Download

Synthesis, Characterization, Tautomeric Structure and Solvatochromic Behavior of Novel 4-(5-Arylazo-2-Hydroxystyryl)-1-Methylpyridinium Iodide as Potential Molecular Photoprobe

Materials, 2016

A novel series of the title compound 4-(5-arylazo-2-hydroxystyryl)-1-methylpyridinium iodide 6 ha... more A novel series of the title compound 4-(5-arylazo-2-hydroxystyryl)-1-methylpyridinium iodide 6 has been synthesized via condensation reactions of the arylazosalicylaldehyde derivatives 4a-i with 1-methyl-picolinium iodide 5. The structures of the new arylazo compounds were characterized by 1 H NMR, IR, mass spectroscopy, as well as spectral and elemental analyses. The electronic absorption spectra of arylazomerocyanine compounds 6 were measured in different buffer solutions and solvents. The pK s and pK* s in both the ground and excited states, respectively, were determined for the series and their correlations with the Hammett equation were examined. The results indicated that the title arylazomerocyanine dyes 6 exist in the azo form 6A in both ground and excited states. The substituent and solvent effects (solvatochromism) of the title compound arylazomerocyanine dyes were determined using the Kamlet-Taft equation and subsequently discussed.

Download

Distributed Classification Using Oiki DDM Model

Chem Erde Geochemistry, Aug 15, 2002

Distributed Data Mining is the process of extracting hidden knowledge from distributed data sourc... more Distributed Data Mining is the process of extracting hidden knowledge from distributed data sources. A number of DDM architectures are proposed during the last few years. Recently, Optimized Incremental Knowledge Integration Distributed Data Mining model is proposed. It is a mobile-agent based model that overcomes the drawbacks of the traditional models. In this paper, the classification mining is formulated using this new model in order to make it scalable to large amounts of data. The proposed model uses meta-learning methodology to integrate the generated knowledge.

MEMS tunable Michelson interferometer with robust beam splitting architecture

2009 IEEE/LEOS International Conference on Optical MEMS and Nanophotonics, 2009

... (2). B. Saadany, M. Medhat, and D. Khalil are with the MEMS Division of Si-Ware Systems, 3 Kh... more

Mohamed Medhat

Uploads

Papers by Mohamed Medhat

Log In