Factors Associated with Early Adverse Events after Coronary Artery Bypass Grafting Subsequent to Percutaneous Coronary Intervention

Yasser Ali Kamal, M.Sc.,Yasser Shaban Mubarak, M.D.,Ashraf Ali Alshorbagy, M.D. 대한흉부외과학회 2016 Journal of Chest Surgery (J Chest Surg) Vol.49 No.3

Background: A previous percutaneous coronary intervention (PCI) may affect the outcomes of patients who undergo coronary artery bypass grafting (CABG). The objective of this study was to compare the early in-hospital postoperative outcomes between patients who underwent CABG with or without previous PCI. Methods: The present study included 160 patients who underwent isolated elective on-pump CABG at the department of cardiothoracic surgery, Minia University Hospital from January 2010 to December 2014. Patients who previously underwent PCI (n=38) were compared to patients who did not (n=122). Preoperative, operative, and early in-hospital postoperative data were analyzed. The end points of the study were in-hospital mortality and postoperative major adverse events. Results: Non-significant differences were found between the study groups regarding preoperative demographic data, risk factors, left ventricular ejection fraction, New York Heart Association class, EuroSCORE, the presence of left main disease, reoperation for bleeding, postoperative acute myocardial infarction, a neurological deficit, need for renal dialysis, hospital stay, and in-hospital mortality. The average time from PCI to CABG was 13.9±5.4 years. The previous PCI group exhibited a significantly larger proportion of patients who experienced in-hospital major adverse events (15.8% vs. 2.5%, p=0.002). On multivariate analysis, only previous PCI was found to be a significant predictor of major adverse events (odds ratio, 0.16; 95% confidence interval, 0.03 to 0.71; p=0.01). Conclusion: Previous PCI was found to have a significant effect on the incidence of early major adverse events after CABG. Further large-scale and long-term studies are recommended.

Pneumothorax secondary to acupuncture in an adolescent girl

Yasser AlFraih,Hasan S. Merali 대한소아응급의학회 2021 대한소아응급의학회지 Vol.8 No.1

Although acupuncture is a form of traditional Chinese medicine that is gaining popularity and usage in children, the relevant complications are rarely reported. We present a case of 17-year-old girl who underwent acupuncture. The girl visited the emergency department with chest pain and dyspnea on the day after receiving the acupuncture. A chest radiograph showed a left-sided pneumothorax. She was hospitalized for observation and supplemental oxygen, and improvement was noted on follow-up radiograph. She continued to follow up in the outpatient clinic until complete resolution of the pneumothorax. Raising awareness of the potential complications of acupuncture is crucial to aid in patient education and establishment of safety guidelines.

Egypt's Science and Technology Parks Outlook : A Focus on SRTACity : City for Scientific Research and Technology Applications

Yasser R. Abdel-Fattah,Abdel-Hady B. Kashyout,Walaa M. Sheta 세계과학도시연합 2013 World Technopolis Review Vol.2 No.2

Egypt has been known as the light house of science and innovation not only in the Middle East but to the world across ages. Recently, there have been many ups and downs that positioned Egypt in a lower rank that it actually deserves according to its long history. This review entitles the current condition of science, technology and innovation in Egypt and the consequent setting up of best practices of science and technology parks (STPs) experiences. Egypt’s science, technology and innovation (STI) system is highly centralized and dominated by the public sector, with R&D happening mostly in state-run universities and research centers supervised by the Ministry of Higher Education and Ministry of Scientific Research. R&D indicators state that Egypt ranking is 40th worldwide for the published articles (around 10,000 papers in 2011), while the numbers of issued patents (350 local and 50 international in 2011) is still far beyond expected. STPs in Egypt are addressed in this review by three examples; smart village in Cairo, Investment zone in Borg El-Arab City and Technology Valley in Ismailia. The three models are discussed in details and a suggested road map for developing more STPs is estimated.

A Novel Technique of Purse-string with barbed suture for Circular-stapled Esophagojejunostomy in Laparoscopic Assisted Total Gastrectomy

Yasser M. ALMAHDI,Tae Sung SOHN,Jeong Eun SEO,Sung Eun OH,Ji Yeong AN,Min-Gew CHOI,Jun Ho LEE,Jae Moon BAE,Sung KIM 대한외과학회 2019 대한외과학회 학술대회 초록집 Vol.2019 No.10

Self-Initiated Imitation Learning. Discovering what to imitate

Yasser Mohammad,Toyoaki Nishdia 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

Imitation learning is an important area in robotics and agents research because it provides an easy way for robot programming and also a bootstrapping technique for social learning. Available learning by imitation systems implicitly or explicitly assume that the boundaries of the actions to be imitated are set by the demonstrator and that the robot is in some imitation mode during the whole interaction session. A less researched area is self-initiated imitation in which the robot needs to decide for itself what to imitate from another imitatee that may not be actively involved in the demonstration process. In this paper, we propose a self-initiated imitation engine based on combining techniques from time-series analysis and causality discovery. The paper also reports a series of proof of concept experiments using simulated and real robots. These evaluations show that the proposed approach is capable of discovering important patterns of behavior during the interaction session and faithfully reproduces them.

Synthesis of Nanoscale Zerovalent Iron Particle and Its Application to Cr(6) Removal from Aqueous Solutions

( Yasser M. Awad ),( Ahmed A. Abdelhafez ),( Mahtab Ahmad ),( Sang Soo Lee ),( Rog Young Kim ),( Jwa Kyung Sung ),( Yong Sik Ok ) 한국환경농학회 2010 한국환경농학회지 Vol.29 No.4

Zerovalent iron (ZVI) is one of the most commonly used metallic reducing agents for the treatment of toxic contaminants in wastewater. Traditional ZVIs are less effective than nanoscale ZVI (nZVI) due to prolonged reaction time. However, the reactivity can be significantly increased by reducing the size of ZVI particles to nanoscale. In this study, nZVI particles were synthesized under laboratory condition and their efficiency in removing hexavalent chromium (Cr(VI)) from aqueous solutions were compared with commercially available ZVI particles. The results showed that the synthesized nZVI particles (SnZVI) reduced >99% of Cr(VI) at the application rate of 0.2% (w/v), while commercial nZVI (CnZVI) particles resulted in 59.6% removal of Cr(VI) at the same application rate. Scanning electron micrographs (SEM) and energy dispersive spectra (EDS) of the nZVI particles revealed the formation of Fe-Cr hydroxide complex after reaction. Overall, the SnZVI particles can be used in treating chromium contaminated wastewater.

An Efficient Sweeping Beamforming Technique for Low-Altitude Platform-to-Sensor Communications

Yasser Albagory 한국통신학회 2021 ICT Express Vol.7 No.1

This paper develops a new technique for generating sweeping beams that originated from low-altitude drone platform to improve the communications performance and energy consumption at sensor nodes. The proposed technique uses two-dimensional array weighted by cosine-square amplitude profile with linear phase shift to enhance the received signal strength from sensors which reduces the energy consumption compared with continuous transmission in conventional wireless sensor networks. The analysis of the proposed technique shows that a sweeping area of 200-meter diameter can be served at the sub-drone point using an array of 14 × 14 elements with the proposed amplitude feeding.

Lateral Torsional Buckling Capacity Assessment of Castellated Steel Beams Using Artifi cial Neural Networks

Yasser Sharifi,Mahmoud Hosseinpour,Adel Moghbeli,Hojjat Sharifi 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.5

A new model based on Artifi cial Neural Network (ANN) was established as a trustworthy technique for predicting ultimate lateral torsional buckling (LTB) capacity of castellated steel beams. The required information for training, validating and testing of the developed model obtained from a reliable database. Consequently, a new formulation based on the ANN has been off ered for predicting the failure load of castellated steel beams exposed to LTB. All parameters which may aff ect the LTB capacity of castellated beams were considered for presentation of this formula. Then, outcomes of the proposed formula were compared with predictions of Australian Standard (AS4100) for LTB capacity of castellated beams. This comparison indicated that proposed formula has a good performance for prediction of ultimate strength in castellated beams subjected to LTB. At the end, Garson’s algorithm has been established as a sensitivity analysis to determinate importance of each input in the proposed formula.

Preconditioning of Human Decidua Basalis Mesenchymal Stem/Stromal Cells with Glucose Increased Their Engraftment and Anti-diabetic Properties

Yasser Basmaeil,Manar Al Rashid,Tanvir Khatlani,Manal AlShabibi,Eman Bahattab,Meshan L. Abdullah,Fawaz Abumary,Bill Kalionis,Safia Massoudi,Mohammad AbuMaree 한국조직공학과 재생의학회 2020 조직공학과 재생의학 Vol.17 No.2

Background: Mesenchymal stem/stromal cells (MSCs) from the decidua basalis (DBMSCs) of the human placenta have important functions that make them potential candidates for cellular therapy. Previously, we showed that DBMSC functions do not change significantly in a high oxidative stress environment, which was induced by hydrogen peroxide (H2O2) and immune cells. Here, we studied the consequences of glucose, another oxidative stress inducer, on the phenotypic and functional changes in DBMSCs. Methods: DBMSCs were exposed to a high level of glucose, and its effect on DBMSC phenotypic and functional properties was determined. DBMSC expression of oxidative stress and immune molecules after exposure to glucose were also identified. Results: Conditioning of DBMSCs with glucose improved their adhesion and invasion. Glucose also increased DBMSC expression of genes with survival, proliferation, migration, invasion, anti-inflammatory, anti-chemoattractant and antimicrobial properties. In addition, DBMSC expression of B7H4, an inhibitor of T cell proliferation was also enhanced by glucose. Interestingly, glucose modulated DBMSC expression of genes involved in insulin secretion and prevention of diabetes. Conclusion: These data show the potentially beneficial effects of glucose on DBMSC functions. Preconditioning of DBMSCs with glucose may therefore be a rational strategy for increasing their therapeutic potential by enhancing their engraftment efficiency. In addition, glucose may program DBMSCs into insulin producing cells with ability to counteract inflammation and infection associated with diabetes. However, future in vitro and in vivo studies are essential to investigate the findings of this study further.

The complex viscosity of polymer carbon nanotubes nanocomposites as a function of networks properties

Yasser Zare,Vesna Mišković‑Stanković,Kyong Yop Rhee 한국탄소학회 2019 Carbon Letters Vol.29 No.5

Cross model correlates the dynamic complex viscosity of polymer systems to zero complex viscosity, relaxation time and power-law index. However, this model disregards the growth of complex viscosity in nanocomposites containing filler networks, especially at low frequencies. The current paper develops the Cross model for complex viscosity of nanocomposites by yield stress as a function of the strength and density of networks. The predictions of the developed model are compared to the experimental results of fabricated samples containing poly(lactic acid), poly(ethylene oxide) and carbon nanotubes. The model’s parameters are calculated for the prepared samples, and their variations are explained. Additionally, the significances of all parameters on the complex viscosity are justified to approve the developed model. The developed model successfully estimates the complex viscosity, and the model’s parameters reasonably change for the samples. The stress at transition region between Newtonian and power-law behavior and the power-law index directly affects the complex viscosity. Moreover, the strength and density of networks positively control the yield stress and the complex viscosity of nanocomposites. The developed model can help to optimize the parameters controlling the complex viscosity in polymer nanocomposites.