Novel CCII-based Field Programmable Analog Array and its Application to a Sixth-Order Butterworth LPF

In this paper, a field programmable analog array (FPAA) is proposed. The proposed FPAA consists of seven configurable analog blocks (CABs) arranged in a hexagonal lattice such that the CABs are directly connected to each other. This structure improves the overall frequency response of the chip by decreasing the parasitic capacitances in the signal path. The CABS of the FPAA is based on a novel fully differential digitally programmable current conveyor (DPCCII). The programmability of the DPCCII is achieved using digitally controlled three-bit MOS ladder current division network. No extra biasing circuit is required to generate specific analog control voltage signals. The DPCCII has constant standby power consumption, offset voltage, bandwidth and harmonic distortions over all its programming range. A sixth-order Butterworth tunable LPF suitable for WLAN/WiMAX receivers is realized on the proposed FPAA. The filter power consumption is 5.4mW from 1V supply; it’s cutoff frequency is tuned from 5.2 MHz to 16.9 MHz. All the circuits are realized using 90nm CMOS technology from TSMC. All simulations are carried out using Cadence

Gold Nanoparticles: Synthesis, Surface Modification and Functionalization for Biomedical Applications

The nanoparticles (NPs) surface plays an important role in the interaction of the NPs with surrounding environments, defines their fate in the biological media and it can be engineered to provide a large number of functional groups for different applications. The main topic of this thesis is the synthesis, the surface modification and the characterization of gold NPs (GNPs). The NPs were prepared with different sizes (up to 100 nm) and shapes (spherical and rods). The employed NPs were prepared originally in aqueous medium, stabilized by citric ions in case of spherical GNPs (SGNPs) and by hexadecyltrimethylammonium bromide (CTAB) in case of gold nanorods (GNRs). These ligand molecules are weakly bound to the NPs surface and thus, they are unsuitable for biomedical applications. Stabilizing of these NPs was the target of this work and then, it was achieved by exchange these ligands by other molecules with higher affinity and finally wrapping the NPs with an amphiphilic polymer (poly(isobutylene-alt-maleic anhydride) dodecylamine grafted, (PMA)). The polymer coating technique has been used over the past years for coating of NPs, which are synthesized originally, and only dispersible in organic media. The NPs obtained using this methodology are highly stable in physiological media. Aiming to use this technique in water-soluble NPs, a new round-trip process was developed using a phase transfer step before the polymer coating. The NPs were stabilized with α-metoxi-ω-thiol-poly-(ethyleneglycol)- (PEG) chains (mPEG-SH (Mw= 750 Da)) and then transferred from water to chloroform using dodecylamine (DDA). The DDA-capped NPs were coated with a modified amphiphilic polymer due to the hydrophobic interaction between the hydrophobic ligands (carbon chains) on the surface of the NPs and the hydrophobic side chains of the used polymer. The resulted polymer coated NPs were cleaned and characterized using different techniques, such as agarose gel electrophoresis, UV-Vis spectroscopy, dynamic light scattering (DLS), laser Doppler anemometry (LDA) and transmission electron microscopy (TEM). Furthermore, the surface of the polymer-coated NPs was modified using different molecular weight of PEG to provide them with higher colloidal stability and prevent the formation of the so-called protein corona. The colloidal stability of all particles was assayed against different biological media via UV-Vis spectroscopy and DLS. The toxicity of these NPs was tested in cancer and non-cancer cells lines showing no-toxicity up to 1 mg/mL concentration levels. Additionally, the effect of NPs size, shape, and surface coating on their interaction with plasma proteins and blood cells was studied

Design of Observer-Based Robust Power System Stabilizers

Power systems are subject to undesirable small oscillations that might grow to cause system shutdown and consequently great loss of national economy. The present manuscript  proposes two  designs for observer-based robust power system stabilizer (PSS) using Linear Matrix Inequality (LMI) approach to damp such oscillations. A model to describe power system dynamics for different loads is derived in the norm-bounded form. The first controller design is based on the derived model to achieve  robust stability against load variation. The design is based on a new Bilinear matrix inequality (BMI) condition. The BMI optimization  is solved interatively in terms of Linear Matrix Inequality (LMI) framework. The condition contains a symmetric positive definite full matrix to be obtained, rather than the commonly used block diagonal form. The difficulty in finding a feasible solution is thus alleviated. The resulting LMI is of small size, easy to solve. The second PSS design shifts the closed loop poles in a desired region so as to achieve a favorite  settling time and damping ratio via a non-iterative solution to a set of LMIs.  The approach provides a systematic way to design a robust output feedback PSS which  guarantees good dynamic performance for different loads. Simulation results based on single-machine and multi-machine power system models verify the ability of the proposed PSS to satisfy control objectives for a wide range of load conditions

Reinforcement larning in gaming

Mestrado em IPB-ESTGA inteligência artificial em videojogos é uma área de investigação de longa data. É um conceito importante em muitos jogos e estuda como utilizar tecnologias de IA para alcançar o desempenho a nível humano durante o jogo. No entanto, quando se trata de IA e videojogos, a Reinforcement Learning tem de ser mencionada. RL define os agentes que enfrentam os problemas que aprendem a tomar boas decisões apenas através da acção e observação. Este projecto centra-se na integração de um algoritmo de Machine Learning chamado Reinforcement Learning no desenvolvimento de um videojogo do género Tower Defense. O projeto foi desenvolvido pelo motor Unity3D que incorpora um agente que utiliza a técnica RL para simular o comportamento de um jogador humano e continuar a melhorá-lo, com base em experiências de jogo anteriores, até ser totalmente optimizado com uma pontuação imbatível pelo jogador médio. O agente irá imitar o comportamento de um humano, comprando, actualizando e colocando torres enquanto obtém a pontuação mais alta, utilizando o menor número de moedas. Além disso, o relatório irá também rever vários conceitos de Aprendizagem Automática, incluindo o Processo de Decisão de Markov e o Q-Learning.Artificial intelligence in video games is a longstanding research area. It is a major concept in a lot of games and it studies how to use AI technologies to achieve human-level performance when playing games. However, when it comes to AI and video games, Reinforcement Learning has to be mentioned. RL defines the problem-facing agents that learn to make good decisions through action and observation alone. This project focuses on integrating a Machine Learning algorithm called Reinforcement Learning in the development of a video game of the Tower Defense genre developed by the Unity3D engine that incorporates an agent that uses the RL technique to simulate the behavior of a human player and keep on improving it, based on previous game experiences, until it’s fully optimized with a score unbeatable by the average player. The agent will imitate the behavior of a human, buying, upgrading, and placing towers while getting the highest score by using the lowest number of currencies. Moreover, the report will also review several Machine Learning concepts, including Markov-Decision Process and Q-Learning

Neuroglial Mechanisms Involved In The Anti-Inflammatory Effect Of Acetate Supplementation

Acetate supplementation increases brain acetyl-CoA and attenuates lipopolysaccharide (LPS)-induced neuroinflammation in vivo. To explain the anti-inflammatory effect of acetate treatment, we proposed that acetate treatment disrupts inflammatory signaling in microglia and astrocytes, and induces histone hyperacetylation known to be correlated with anti-inflammatory properties. To test this hypothesis, we measured the effects that LPS and acetate treatment had on histone acetylation, mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB), and eicosanoid signaling. A single oral dose of acetate treatment (6 g/kg) in normal animals induced a time- and site-specific pattern of histone hyperacetylation, associated with reduction of histone deacetylase (HDAC) activity and expression. Long-term acetate treatment over 28 days induced the same site-specific pattern of histone hyperacetylation, and reversed LPS-induced histone H3 at lysine 9 (H3K9) hypoacetylation and interleukin (IL)-1β expression. In LPS-stimulated BV-2 microglia, acetate treatment reversed LPS-induced H3K9 hypoacetylation, IL-1β, IL-6, tumor necrosis factor (TNF)-α, cyclooxygenase (Cox)-1 and 2 protein levels, and NF-κB p65 protein level and phosphorylation at serine 468. Further, acetate treatment increased IL-4 and transforming growth factor (TGF)-β1 expression, and NF-κB p65 acetylation at lysine 310. Conversely, acetate treatment did not alter LPS-induced cytosolic (c) phospholipase A2 (PLA2), transiently reduced MAPK p38 and JNK phosphorylation, and increased MAPK ERK1/2 phosphorylation. In LPS-stimulated astrocyte, acetate treatment induced H3K9 hyperacetylation, reversed LPS-induced increases in IL-1β, TNF-α, NF-κB p65, and Cox-1 protein levels, MAPK p38 and cPLA2 phosphorylation and PGE2 release, and reversed LPS-induced decreases in TGF-β1 and IL-4. Moreover, acetate treatment reduced basal levels of IL-6, phosphorylated ERK1/2 and NF-κB p65 at serine 536, sPLA2 IIA and PLCβ1. Acetate treatment also increased acetylated H3K9 bound to the promoters of the genes of Cox-1, Cox-2, IL-1β and NF-κB p65, but not IL-4 in BV-2 microglia, which suggests that acetate treatment-induced H3K9 hyperacetylation can potentially be involved in the alteration of the expression of these genes. These data suggest that acetate treatment has net anti-inflammatory effects in vivo and in vitro both in LPS-stimulated microglia and astrocyte cultures through neuroglial cell type-distinct mechanisms

Novel therapeutic approach for regulating the susceptibility of epitheliato adenovirus infection

Human Adenoviruses (AdVs) are etiologic agents for respiratory tract, digestive tract, heart, and eye infections. Although most AdV infections are self-resolving, some infections progress to acute respiratory disease with up to 50% mortality, particularly in immunosuppressed people. Except for vaccines for serotypes, 4 and 7, serotypes that are prevalent in the military, no vaccines or therapeutics that specifically prevent or treat AdV infection exist. On the other hand, AdV remains the most common vector system used in gene therapy clinical trials worldwide and several AdV vectors show promise in phase III clinical trials. The majority of AdVs use the coxsackievirus and adenovirus receptor (CAR) as a primary receptor. We have characterized an alternatively spliced eight-exon containing isoform (CAREx8) that localizes at the apical surface of epithelial cells and is responsible for the initiation of apical AdV infection. A cellular scaffold protein named Membrane Associated Guanylate Kinase, WW and PDZ Domain Containing 1 (MAGI-1) directly interacts with and alternatively regulates CAREx8 through the C-terminal PDZ-binding domain. The alternative regulation is due to the interaction with two different domains, namely PDZ1 and PDZ3, within the same molecule (MAGI-1). I hypothesized that cell permeable peptides that target the interaction between MAGI-1 PDZ1 domain and CAREx8 (TAT-PDZ1) would be able to decrease CAREx8 protein levels and prevent AdV infection. On the other hand, peptides that target the interaction between MAGI-1 PDZ3 domain and CAREx8 (TAT-PDZ3) would be able to increase CAREx8 and enhance AdV mediated gene therapy. Decoy peptides that target the assigned domain were synthesized and conjugated to TAT cell permeable peptide to facilitate peptide entry (TAT-PDZ1; TAT-NET1, TAT-E6) or (TAT-PDZ3; TAT-CAREx8-9c, TAT-ESAM). Peptide entry into the polarized epithelia was confirmed by mass spectroscopy and fluorescence microscopy. Treatment with TAT-PDZ1 peptides decreased the cellular levels of CAREx8 and suppressed AdV transduction in MDCK, human airway epithelia (HAE), as well as epithelia from cotton rats, an animal model of AdV pathogenicity. To determine the mechanism of peptide action, CAREx8 localization was tracked by immunofluorescence. Interestingly, TAT-PDZ1 caused nuclear translocation of CAREx8 C-term domain, an effect that was reversed by ADAM17 inhibitor (TIMP3) and ¿-secretase inhibitor (Comp E), implicating the regulated intramembrane proteolysis (RIP) pathway. Immunoprecipitation and direct ligand binding assays showed that ADAM17 interacts specifically with MAGI-1 PDZ2 domain, suggesting that TAT-PDZ1 peptides caused CAREx8 degradation by enhancing the proximity of the substrate (CAREx8) and enzyme (ADAM17). Finally, ADAM17 caused CAREx8 extracellular domain (ECD) shedding that was able to significantly decrease AdV-GFP transduction, indicating a second protective role against AdV entry by the shed ECD of CAREx8. By contrast, TAT-PDZ3 peptides increased the levels of CAREx8 and significantly increased AdV entry and transduction in MDCK, HAE, and cotton rat epithelia. Upon TAT-PDZ3 peptide administration, CAREx8 was localized in vesicular pattern compartments distinct from MAGI-1 and spread throughout the apical trafficking pathway and at the apical surface of the epithelium. Investigation of the trafficking pathway of CAREx8 using Rabs reveal the possibility of CAREx8 is residing within the recycling Endosomal-Golgi pathway. Neither TAT-PDZ1 nor TAT-PDZ3 binding peptides altered epithelium formation, as measured by transepithelial resistance (TER) as well as dextran permeability across the epithelia, indicating the safety of the peptides on epithelial integrity. Moreover, intranasal administration of TAT-PDZ3 peptides increased AdV transduction by 300-500% while TAT-PDZ1 peptides decreased AdV transduction by 80-95% after intrana..

Development of High Efficiency Partial Nitrification as a First Step of Nitrite Shunt Process using Ammonium-Oxidizing Bacteria (AOB)

Shortcut biological nitrogen removal is a non-conventional way of removing nitrogen from wastewater using two processes either nitrite shunt or deammonification. In this research, a complete partial nitrification as a first step of the Nitrite Shunt process has been developed under a high nitrogen loading rate (NLR) using a novel strategy to control the DO depending on using a constant air flow rate with a variable mixing speed using a Sequential Batch Reactor (SBR). The SBR has been successfully running at NLR of 1.2 kg/ (m3.d) maintaining an ammonia removal efficiency (ARE) of 98.6 ± 2.8% with a nitrite accumulation rate (NAR) of 93.0 ± 0.7%, which is 2 times higher than the previous NLR reported in the literature. Moreover, a dynamic and pseudo-state model of partial nitrification has been developed and calibrated using BioWin software for long-term dynamic behavior of the lab-scale SBR at different nitrogen loading rates (NLR)

Análisis de la interlengua en el proceso aprendizaje y adquisición del español como lengua extranjera: el caso de aprendices arabófonos.

El presente trabajo busca brindar un acercamiento a la interlengua de los hablantes arabófonos a través de un análisis de error en su producción escrita. El concepto de la interlengua tiene que ver con la relación entre la lengua materna (LM) y otra lengua que se denomina objeto (LO). Esta mezcla entre la LM y la LO genera lo que llamamos transferencia lingüística, la cual a su vez es llamada interferencia cuando los aprendices usan reglas o sonidos de su LM en la LO de manera incorrecta. Las interferencias negativas siempre están presentes en el proceso de apropiación de un idioma y son un obstáculo para los aprendices. El objetivo de este trabajo es caracterizar la interlengua de los arabófonos en dos contextos diferentes, con el propósito de identificar aquellas interferencias que cometen. De hecho, la investigación lleva a cabo un análisis comparativo entre la interlengua formada a través de un proceso formal de aprendizaje y otro proceso informal de adquisición. De esta manera, la idea es comparar la producción escrita de un grupo de estudiantes del español como lengua extranjera (ELE) que viven en Egipto, y otro grupo de inmigrantes que viven en un país de habla española (Colombia). Para lograr ese objetivo hemos implementado como metodología para este estudio la lingüística del corpus (LC). La base metodológica de la LC, se enfoca en el análisis de un fenómeno lingüístico en el uso real de la lengua. Según los resultados del análisis del corpus se ha evidenciado que la LM influye en ambos procesos generando interferencias negativas. Por otro lado, hemos identificado aquellas interferencias en los dos contextos y en qué nivel lingüístico ocurren con mayor frecuencia.Magister en Enseñanza de Lenguas ExtranjerasMaestrí

The Effect of Ownership Structure on Firm’s Financial Performance: An Empirical Study on the Most Active Firms in the Egyptian Stock Exchange

This paper seeks to examine the effect of ownership structure on firm financial performance in Egypt. Using a sample of 50 more active Egyptian companies listed on the Egyptian Stock Exchange of the non-financial sector covering the period of three financial years from 2007 to 2009. Ownership Structure is represented by Managerial Ownership, Institutional Ownership, Block holder Ownership and Free Float Ownership. Return on Assets (ROA) and Return on Equity (ROE) are used as a proxy for Firm financial Performance. Using multiple linear regressions as method of estimation, the results provide evidences that there is no significant relationship between ownership structure variables and firm financial performance measures by (ROA and ROE). This study provides many recommendations to the regulatory authorities in Egypt regarding ways to strengthen and reinforce the internal governance structure of companies especially ownership structure. Keywords: Corporate governance, Ownership structure, Firm Financial Performance, Egyp

Exploring Cyber-Physical Systems’ Security Governance in the Oil and Gas Industry

The Fourth Industrial Revolution, which utilizes modern communication-dependent technologies, including cyber-physical systems (CPS), has made exploration and production operations more efficient in the oil and gas industry. CPS in this industry should be secured against operational threats to prevent interruption of critical oil and gas supplies and services. However, these systems are vulnerable to cyberattacks, and many oil and gas companies have not incorporated effective cybersecurity measures into their corporate management strategies. This qualitative, multiple-case study, which was guided by the routine activity theory, explored how cybersecurity governance was applied to develop controls that stopped or mitigated the consequences of cyberattacks against the CPS. Interview-based data were obtained through Zoom meetings with 20 global cybersecurity experts selected from cybersecurity-specialized groups on LinkedIn. These data were then triangulated with global CPS cybersecurity governance standards and methods. The data analysis resulted in nine themes, including CPS vulnerabilities and failure consequences, predominant cybersecurity governance, the efficiency of cybersecurity governance, governance challenges, offenders and motives, cybersecurity enhancement, CPS governance endorsement, cybersecurity performance assessment, and governance mandate. This study’s implications for positive social change include recommendations for applying cybersecurity governance strategies that reduce health and environmental incidents and prevent interruption of critical oil and gas deliveries due to cyberattacks. These results may also help improve the living conditions of the communities surrounding oil and gas fields and similar CPS-based industries worldwide