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result(s) for
"Abdelrasoul, Mohamed M. M."
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Structure of the moiré exciton captured by imaging its electron and hole
by
Pareek, Vivek
,
Zhu, Xing
,
Heinz, Tony F.
in
639/624/399
,
639/766/119/1000/1018
,
639/925/357/1018
2022
Interlayer excitons (ILXs) — electron–hole pairs bound across two atomically thin layered semiconductors — have emerged as attractive platforms to study exciton condensation
1
–
4
, single-photon emission and other quantum information applications
5
–
7
. Yet, despite extensive optical spectroscopic investigations
8
–
12
, critical information about their size, valley configuration and the influence of the moiré potential remains unknown. Here, in a WSe
2
/MoS
2
heterostructure, we captured images of the time-resolved and momentum-resolved distribution of both of the particles that bind to form the ILX: the electron and the hole. We thereby obtain a direct measurement of both the ILX diameter of around 5.2 nm, comparable with the moiré-unit-cell length of 6.1 nm, and the localization of its centre of mass. Surprisingly, this large ILX is found pinned to a region of only 1.8 nm diameter within the moiré cell, smaller than the size of the exciton itself. This high degree of localization of the ILX is backed by Bethe–Salpeter equation calculations and demonstrates that the ILX can be localized within small moiré unit cells. Unlike large moiré cells, these are uniform over large regions, allowing the formation of extended arrays of localized excitations for quantum technology.
Imaging the electron and hole that bind to form interlayer excitons in a 2D moiré material enables direct measurement of its diameter and indicates the localization of its centre of mass.
Journal Article
Moiré-localized interlayer exciton wavefunctions captured by imaging its electron and hole constituents
2021
Interlayer excitons (ILXs) - electron-hole pairs bound across two atomically thin layered semiconductors - have emerged as attractive platforms to study exciton condensation, single-photon emission and other quantum-information applications. Yet, despite extensive optical spectroscopic investigations, critical information about their size, valley configuration and the influence of the moiré potential remains unknown. Here, we captured images of the time- and momentum-resolved distribution of both the electron and the hole that bind to form the ILX in a WSe2/MoS2 heterostructure. We thereby obtain a direct measurement of the interlayer exciton diameter of ~5.4 nm, comparable to the moiré unit-cell length of 6.1 nm. Surprisingly, this large ILX is well localized within the moiré cell to a region of only 1.8 nm - smaller than the size of the exciton itself. This high degree of localization of the interlayer exciton is backed by Bethe-Salpeter equation calculations and demonstrates that the ILX can be localized within small moiré unit cells. Unlike large moiré cells, these are uniform over large regions, thus allowing the formation of extended arrays of localized excitations for quantum technology.
Review on the Development of Mining Method Selection to Identify New Techniques Using a Cascade-Forward Backpropagation Neural Network
by
Ali, Mahrous A. M.
,
Abd-El-Hakeem Mohamed, Mohamed
,
Abdelrasoul, Mohamed E. I.
in
Ambiguity
,
Artificial intelligence
,
Back propagation
2022
The most crucial event in a mining project is the selection of an appropriate mining method (MMS). Consequently, determining the optimal choice is critical because it impacts most of the other key decisions. This study provides a concise overview of the development of multiple selection methods using a cascade-forward backpropagation neural network (CFBPNN). Numerous methods of multicriteria decision-making (MCDM) are discussed and compared herein. The comparison includes several factors, such as applicability, subjectivity, qualitative and quantitative data, sensitivity, and validity. The application of artificial intelligence is presented and discussed using CFBPNN. The Chengchao iron mine was selected for this investigation to pick the optimum mining method. The results revealed that cut and fill stoping is the most appropriate mining method, followed by sublevel and shrinkage stoping methods. The least appropriate method is open-pit mining, followed by room and pillar and longwall mining methods.
Journal Article
Enhancement of cellulolytic enzyme production from intrageneric protoplast fusion of Aspergillus species and evaluating the hydrolysate scavenging activity
by
Abdelrasoul, Hager A.
,
Goda, Doaa A.
,
Shakam, Huda M.
in
Analysis
,
Antioxidants
,
Applied Microbiology
2024
Background
Lignocellulosic biomass provides a great starting point for the production of energy, chemicals, and fuels. The major component of lignocellulosic biomass is cellulose, the employment of highly effective enzymatic cocktails, which can be produced by a variety of microorganisms including species of the genus
Aspergillus
, is necessary for its utilization in a more productive manner. In this regard, molecular biology techniques should be utilized to promote the economics of enzyme production, whereas strategies like protoplast fusion could be employed to improve the efficacy of the hydrolytic process.
Results
The current study focuses on cellulase production in
Aspergillus
species using intrageneric protoplast fusion, statistical optimization of growth parameters, and determination of antioxidant activity of fermentation hydrolysate. Protoplast fusion was conducted between
A. flavus
X
A. terreus
(PFFT),
A. nidulans
X
A. tamarii
(PFNT) and
A. oryzae
X
A. tubingensis
(PFOT), and the resultant fusant PFNT revealed higher activity level compared with the other fusants. Thus, this study aimed to optimize lignocellulosic wastes-based medium for cellulase production by
Aspergillus spp.
fusant (PFNT) and studying the antioxidant effect of fermentation hydrolysate. The experimental strategy Plackett-Burman (PBD) was used to assess how culture conditions affected cellulase output, the best level of the three major variables namely, SCB, pH, and incubation temperature were then determined using Box-Behnken design (BBD). Consequently, by utilizing an optimized medium instead of a basal medium, cellulase activity increased from 3.11 U/ml to 7.689 U/ml CMCase. The following medium composition was thought to be ideal based on this optimization: sugarcane bagasse (SCB), 6.82 gm; wheat bran (WB), 4; Moisture, 80%; pH, 4; inoculum size, (3 × 10
6
spores/ml); and incubation Temp. 31.8 °C for 4 days and the fermentation hydrolysate has 28.13% scavenging activities.
Conclusion
The results obtained in this study demonstrated the significant activity of the selected fusant and the higher sugar yield from cellulose hydrolysis over its parental strains, suggesting the possibility of enhancing cellulase activity by protoplast fusion using an experimental strategy and the fermentation hydrolysate showed antioxidant activity.
Journal Article
Retraction Note: Visnagin alleviates rheumatoid arthritis via its potential inhibitory impact on malate dehydrogenase enzyme: in silico, in vitro, and in vivo studies
by
Abdelrasoul, Elsayed A.
,
Mohamed, Tarek M.
,
Salem, Maha M.
in
Biomedical and Life Sciences
,
Biomedicine
,
Clinical Nutrition
2025
Journal Article
Visnagin alleviates rheumatoid arthritis via its potential inhibitory impact on malate dehydrogenase enzyme: in silico, in vitro, and in vivo studies
by
Abdelrasoul, Elsayed A.
,
Mohamed, Tarek M.
,
Salem, Maha M.
in
Adjuvants
,
Angina pectoris
,
animal models
2024
Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder. The present study aimed to evaluate the in silico, in vitro , and in vivo inhibitory effect of visnagin on malate dehydrogenase activity and elucidate its inflammatory efficacy when combined with methotrexate in the RA rat model. The molecular docking, ADMET simulations, MDH activity, expression, and X-ray imaging were detected. Moreover, CRP, RF, (anti-CCP) antibody, (TNF-α), (IL-6), (IL-17), and (IL-10) were evaluated. The expression levels of MMP3 and FOXP3 genes and CD4, CD25, and CD127 protein levels were assessed. Histological assessment of ankle joints was evaluated. The results revealed that visnagin showed reversible competitive inhibition on MDH with inhibitory constant (Ki) equal to 141 mM with theoretical IC50 equal to 1202.7 mM, LD50 equal to 155.39 mg/kg, and LD25 equal to 77.69 mg/kg. In vivo studies indicated that visnagin exhibited anti-inflammatory effects through decreasing MDH1 activity and expression and induced proliferation of anti-inflammatory CD4 + CD25 + FOXP3 regulatory T cells with increasing the anti-inflammatory cytokine IL-10 levels. Moreover, visnagin reduced the levels of inflammatory cytokines and the immuno-markers. Our findings elucidate that visnagin exhibits an anti-inflammatory impact against RA through its ability to inhibit the MDH1 enzyme, improve methotrexate efficacy, and reduce oxidative stress. Graphical Abstract
Journal Article
RETRACTED ARTICLE: Visnagin alleviates rheumatoid arthritis via its potential inhibitory impact on malate dehydrogenase enzyme: in silico, in vitro, and in vivo studies
by
Abdelrasoul, Elsayed A.
,
Mohamed, Tarek M.
,
Salem, Maha M.
in
Biomedical and Life Sciences
,
Biomedicine
,
Clinical Nutrition
2024
Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder. The present study aimed to evaluate the in silico, in vitro
,
and in vivo inhibitory effect of visnagin on malate dehydrogenase activity and elucidate its inflammatory efficacy when combined with methotrexate in the RA rat model. The molecular docking, ADMET simulations, MDH activity, expression, and X-ray imaging were detected. Moreover, CRP, RF, (anti-CCP) antibody, (TNF-α), (IL-6), (IL-17), and (IL-10) were evaluated. The expression levels of MMP3 and FOXP3 genes and CD4, CD25, and CD127 protein levels were assessed. Histological assessment of ankle joints was evaluated. The results revealed that visnagin showed reversible competitive inhibition on MDH with inhibitory constant (Ki) equal to 141 mM with theoretical IC50 equal to 1202.7 mM, LD50 equal to 155.39 mg/kg, and LD25 equal to 77.69 mg/kg. In vivo studies indicated that visnagin exhibited anti-inflammatory effects through decreasing MDH1 activity and expression and induced proliferation of anti-inflammatory CD4
+
CD25
+
FOXP3 regulatory T cells with increasing the anti-inflammatory cytokine IL-10 levels. Moreover, visnagin reduced the levels of inflammatory cytokines and the immuno-markers. Our findings elucidate that visnagin exhibits an anti-inflammatory impact against RA through its ability to inhibit the MDH1 enzyme, improve methotrexate efficacy, and reduce oxidative stress.
Graphical Abstract
Journal Article
The association of LPCAT1-rs9728 polymorphism with cord blood IL-10, MIF, and VEGF levels in neonatal respiratory distress syndrome: a case–control study
by
El-Asheer, Osama Mahmoud
,
Sayed, Ahmed Abdelrasoul
,
El-Baz, Mona Abd El-Hamid Hassan
in
Apgar score
,
Biosynthesis
,
Birth weight
2024
Background
Lysophospholipid acyltransferase (LPCAT) is crucial for surfactant biosynthesis. It is encoded by
LPCAT
genes. We investigated the
LPCAT1
-rs9728 genotypes in neonatal respiratory distress syndrome (NRDS) cases and their possible association with the cord arterial serum interleukin-10 (IL-10), macrophage migration inhibitory factor (MIF), and vascular endothelial growth factor (VEGF) levels.
Methods
The study included 160 neonates grouped into G1: 60 healthy neonates and G2: 100 NRDS cases. IL-10, MIF, and VEGF levels were measured by their corresponding kits. The Gene JETTM Whole Blood Genomic DNA Purification Mini Kit was used to extract the DNA from the newborn venous blood. The quantitative real-time polymerase chain reaction was carried out for
LPCAT1
-rs9728 genotyping.
Results
The IL-10 and MIF levels were significantly higher, while VEGF levels were significantly lower in G2 than in G1. The percentages of
LPCAT1
-rs9728 AA and
LPCAT1
-rs9728 AG genotypes were significantly higher in G2 than in G1. The IL-10 and MIF levels were significantly higher, while the VEGF levels, birth weight, and APGAR score at 1 and 5 min were significantly lower in neonates with
LPCAT1
-rs9728 AA genotype than in neonates with
LPCAT1
-rs9728 AG and
LPCAT1
-rs9728 GG genotypes and in neonates with
LPCAT1
-rs9728 AG genotype than in neonates with
LPCAT1
-rs9728 GG genotype.
Conclusion
There is an association between the LPCAT1
-
rs9728 AA genotype and its A allele and the NRDS development and severity. Further research may provide a better understanding of this association to help future management.
Journal Article
The Role of the MAPK Signaling, Topoisomerase and Dietary Bioactives in Controlling Cancer Incidence
2017
Reactive oxygen species (ROS) are common products of mitochondrial oxidative phosphorylation, xenobiotics metabolism and are generated in response to several environmental stress conditions. Some of them play important biochemical roles in cellular signal transduction and gene transcription. On the other hand, ROS are known to be involved in a wide range of human diseases, including cancer. The excessive production of such ROS together with disruption of homeostasis detoxifying mechanisms can mediate a series of cellular oxidative stresses. The oxidative stress of redundant free radicals production can lead to oxidative denaturation of cellular macromolecules including proteins, lipids and DNA. Moreover, oxidative damage is one of the major causes of DNA mutations, replication errors and genomic abnormalities which result in either inhibition or induction of transcription, and end with the disturbance of signal transduction pathways. Among affected signaling pathways are redox-sensitive kinases. The stimulation of these kinases induces several transcription factors through the phosphorylation of their module proteins. The activation of such pathways induces proliferation and cellular transformation. A diet rich in antioxidant compounds has potential health benefits, and there is a growing interest in the role of natural antioxidants in nutrition for prevention and cure of cancer diseases. A controversy has risen regarding the relation between antioxidants and the significant decrease in the risk of cancer incidence. In this review, we will focus on redox-sensitive kinases signaling pathways, highlighting the effects of dietary antioxidant on the prevention, incidence, prognosis or even treatment of human cancers. In addition, we will place emphasis on the chemical classes of pterocarpans as natural anti-oxidants/cancers as well as their underlying mechanisms of action, including their effects on MAPKs and topoisomerase activities.
Journal Article