Interactive Effects of Morphine on HIV Infection: Role in HIV-Associated Neurocognitive Disorder

HIV epidemic continues to be a severe public health problem and concern within USA and across the globe with about 33 million people infected with HIV. The frequency of drug abuse among HIV infected patients is rapidly increasing and is another major issue since injection drug users are at a greater risk of developing HIV associated neurocognitive dysfunctions compared to non-drug users infected with HIV. Brain is a major target for many of the recreational drugs and HIV. Evidences suggest that opiate drug abuse is a risk factor in HIV infection, neural dysfunction and progression to AIDS. The information available on the role of morphine as a cofactor in the neuropathogenesis of HIV is scanty. This review summarizes the results that help in understanding the role of morphine use in HIV infection and neural dysfunction. Studies show that morphine enhances HIV-1 infection by suppressing IL-8, downregulating chemokines with reciprocal upregulation of HIV coreceptors. Morphine also activates MAPK signaling and downregulates cAMP response element-binding protein (CREB). Better understanding on the role of morphine in HIV infection and mechanisms through which morphine mediates its effects may help in devising novel therapeutic strategies against HIV-1 infection in opiate using HIV-infected population.

Testing the Efficacy of Panax ginseng Extract as a Novel Anti-Quorum Sensing Agent

Quorum sensing (QS) is the phenomenon by which microorganisms regulate gene expression in response to cell-population density. These microorganisms synthesize and secrete small molecules known as autoinducers that increase in concentration as a function of cell density. Once the cell detects the minimal threshold concentration of an autoinducer, the gene expression is altered accordingly. Although the cellular circuitry responding to QS is relatively conserved, the cellular processes regulated by QS, for example are conjugation, motility, sporulation, biofilm formation and production of virulence factors importamt for infection. Since many pathogens have developed resistance to available antibiotics, novel therapies are required to further treat these pathogens. Inhibitors of QS are potential therapeutic candidates since they would inhibit virulence without selecting for antibiotic resistant strains. Previous studies have shown that the Chinese herb Panax ginseng contains compounds that inhibit QS activity. To further characterize this activity, a highly sensitive quantitative liquid assay was developed using a Chromobacterium violaceum AHL mutant, CV026 as a biomonitor strain. After confirmation that P. ginseng aqueous extracts had anti-QS activity, the extract was fractionated on a reverse phase C18 Sep Pak column. Most anti-QS activity was present in the flow through, and compounds eluted with ten percent acetonitrile in water antibacterial activity. We thus conclude that P. ginseng has anti-QS activity and the active compound is water soluble. Compounds from P. ginseng, could be used as a lead structure to design compound with higher anti-QS activity for therapeutic treatments.

Role of Pseudomonas aeruginosa mifSR Two-Component System in Antibiotic Resistance and Biofilm Formation

Pseudomonas aeruginosa is an opportunistic pathogen found in a wide variety of environments. It is one of the leading causes of morbidity and mortality in cystic fibrosis patients, and one of the main sources of nosocomial infections in the United States. One of the most prominent features of this pathogen is its wide resistance to antibiotics. P. aeruginosa employs a variety of mechanisms including efflux pumps and the expression of B-lactamases to overcome antibiotic treatment. Two chromosomally encoded lactamases, ampC and poxB, have been identified in P. aeruginosa. Sequence analyses have shown the presence of a two-component system (TCS) called MifSR (MifS-Sensor and MifR-Response Regulator), immediately upstream of the poxAB operon. It is hypothesized that the MifSR TCS is involved in B-lactam resistance via the regulation of poxB. Recently, the response regulator MifR has been reported to play a crucial role in biofilm formation, a major characteristic of chronic infections and increased antibiotic resistance. In this study, mifR and mifSR deletion mutants were constructed, and compared to the wild type parent strain PAOl for differences in growth and B-lactam sensitivity. Results obtained thus far indicate that mifR and mifSR are not essential for growth, and do not confer B-lactam resistance under the conditions tested. This study is significant because biofilm formation and antibiotic resistance are two hallmarks of P. aeruginosa infections, and finding a link between these two may lead to the development of improved treatment strategies.

Novel hybrid columns made of ultra-high performance concrete and fiber reinforced polymers

The application of advanced materials in infrastructure has grown rapidly in recent years mainly because of their potential to ease the construction, extend the service life, and improve the performance of structures. Ultra-high performance concrete (UHPC) is one such material considered as a novel alternative to conventional concrete. The material microstructure in UHPC is optimized to significantly improve its material properties including compressive and tensile strength, modulus of elasticity, durability, and damage tolerance. Fiber-reinforced polymer (FRP) composite is another novel construction material with excellent properties such as high strength-to-weight and stiffness-to-weight ratios and good corrosion resistance. Considering the exceptional properties of UHPC and FRP, many advantages can result from the combined application of these two advanced materials, which is the subject of this research. The confinement behavior of UHPC was studied for the first time in this research. The stress-strain behavior of a series of UHPC-filled fiber-reinforced polymer (FRP) tubes with different fiber types and thicknesses were tested under uniaxial compression. The FRP confinement was shown to significantly enhance both the ultimate strength and strain of UHPC. It was also shown that existing confinement models are incapable of predicting the behavior of FRP-confined UHPC. Therefore, new stress-strain models for FRP-confined UHPC were developed through an analytical study. In the other part of this research, a novel steel-free UHPC-filled FRP tube (UHPCFFT) column system was developed and its cyclic behavior was studied. The proposed steel-free UHPCFFT column showed much higher strength and stiffness, with a reasonable ductility, as compared to its conventional reinforced concrete (RC) counterpart. Using the results of the first phase of column tests, a second series of UHPCFFT columns were made and studied under pseudo-static loading to study the effect of column parameters on the cyclic behavior of UHPCFFT columns. Strong correlations were noted between the initial stiffness and the stiffness index, and between the moment capacity and the reinforcement index. Finally, a thorough analytical study was carried out to investigate the seismic response of the proposed steel-free UHPCFFT columns, which showed their superior earthquake resistance, as compared to their RC counterparts.

Development and verification of control and protection strategies in hybrid AC/DC power systems for smart grid applications

Modern power networks incorporate communications and information technology infrastructure into the electrical power system to create a smart grid in terms of control and operation. The smart grid enables real-time communication and control between consumers and utility companies allowing suppliers to optimize energy usage based on price preference and system technical issues. The smart grid design aims to provide overall power system monitoring, create protection and control strategies to maintain system performance, stability and security. This dissertation contributed to the development of a unique and novel smart grid test-bed laboratory with integrated monitoring, protection and control systems. This test-bed was used as a platform to test the smart grid operational ideas developed here. The implementation of this system in the real-time software creates an environment for studying, implementing and verifying novel control and protection schemes developed in this dissertation. Phasor measurement techniques were developed using the available Data Acquisition (DAQ) devices in order to monitor all points in the power system in real time. This provides a practical view of system parameter changes, system abnormal conditions and its stability and security information system. These developments provide valuable measurements for technical power system operators in the energy control centers. Phasor Measurement technology is an excellent solution for improving system planning, operation and energy trading in addition to enabling advanced applications in Wide Area Monitoring, Protection and Control (WAMPAC). Moreover, a virtual protection system was developed and implemented in the smart grid laboratory with integrated functionality for wide area applications. Experiments and procedures were developed in the system in order to detect the system abnormal conditions and apply proper remedies to heal the system. A design for DC microgrid was developed to integrate it to the AC system with appropriate control capability. This system represents realistic hybrid AC/DC microgrids connectivity to the AC side to study the use of such architecture in system operation to help remedy system abnormal conditions. In addition, this dissertation explored the challenges and feasibility of the implementation of real-time system analysis features in order to monitor the system security and stability measures. These indices are measured experimentally during the operation of the developed hybrid AC/DC microgrids. Furthermore, a real-time optimal power flow system was implemented to optimally manage the power sharing between AC generators and DC side resources. A study relating to real-time energy management algorithm in hybrid microgrids was performed to evaluate the effects of using energy storage resources and their use in mitigating heavy load impacts on system stability and operational security.

Resistance Performances: (Re)constructing Spaces of Resistance and Contention in the 2010-2011 University of Puerto Rico Student Movement

On the night of April 20, 2010, a group of students from the University of Puerto Rico (UPR), Río Piedras campus, met to organize an indefinite strike that quickly broadened into a defense of accessible public higher education of excellence as a fundamental right and not a privilege. Although the history of student activism in the UPR can be traced back to the early 1900s, the 2010-2011 strike will be remembered for the student activists’ use of new media technologies as resources that rapidly prompted and aided the numerous protests. This activist research entailed a critical ethnography and a critical discourse analysis (CDA) of traditional and alternative media coverage and treatment during the 2010 -2011 UPR student strike. I examined the use of the 2010-2011 UPR student activists’ resistance performances in constructing local, corporeal, and virtual spaces of resistance and contention during their movement. In particular, I analyzed the different tactics and strategies of resistance or repertoire of collective actions that student activists used (e.g. new media technologies) to frame their collective identities via alternative news media’s (re)presentation of the strike, while juxtaposing the university administration’s counter-resistance performances in counter-framing the student activists’ collective identity via traditional news media representations of the strike. I illustrated how both traditional and alternative media (re)presentations of student activism developed, maintained, and/or modified students activists’ collective identities. As such, the UPR student activism’s success should not be measured by the sum of demands granted, but by the sense of community achieved and the establishment of networks that continue to create resistance and change. These networks add to the debate surrounding Internet activism and its impact on student activism. Ultimately, the results of this study highlight the important role student movements have had in challenging different types of government policies and raising awareness of the importance of an accessible public higher education of excellence.

Exoneration or Observation? Examining a Novel Difference Between Liars and Truth Tellers

Individual cues to deception are subtle and often missed by lay people and law enforcement alike. Linguistic statement analysis remains a potentially useful way of overcoming individual diagnostic limitations (e.g. Criteria based Content Analysis; Steller & Köhnken, 1989; Reality monitoring; Johnson & Raye, 1981; Scientific Content Analysis; Sapir, 1996). Unfortunately many of these procedures are time-consuming, require in-depth training, as well as lack empirical support and/or external validity. The current dissertation develops a novel approach to statement veracity analysis that is simple to learn, easy to administer, theoretically sound, and empirically validated. Two strategies were proposed for detecting differences between liars' and truth-tellers' statements. Liars were hypothesized to strategically write statements with the goal of self-exoneration. Liars' statements were predicted to contain more first person pronouns and fewer third person pronouns. Truth-tellers were hypothesized to be motivated toward being informative and thus produce statements with fewer first person pronouns and more third person pronouns. Three studies were conducted to test this hypothesis. The first study explored the verbal patterns of exoneration and informativeness focused statements. The second study used a traditional theft paradigm to examine these verbal patterns in guilty liars and innocent truth tellers. In the third study to better match the context of a criminal investigation a cheating paradigm was used in which spontaneous lying was induced and written statements were taken. Support for the first person pronoun hypothesis was found. Limited support was found for the third person pronoun hypothesis. Results, implications, and future directions for the current research are discussed.

Development and Verification of Control and Protection Strategies in Hybrid AC/DC Power Systems for Smart Grid Applications

Modern power networks incorporate communications and information technology infrastructure into the electrical power system to create a smart grid in terms of control and operation. The smart grid enables real-time communication and control between consumers and utility companies allowing suppliers to optimize energy usage based on price preference and system technical issues. The smart grid design aims to provide overall power system monitoring, create protection and control strategies to maintain system performance, stability and security. This dissertation contributed to the development of a unique and novel smart grid test-bed laboratory with integrated monitoring, protection and control systems. This test-bed was used as a platform to test the smart grid operational ideas developed here. The implementation of this system in the real-time software creates an environment for studying, implementing and verifying novel control and protection schemes developed in this dissertation. Phasor measurement techniques were developed using the available Data Acquisition (DAQ) devices in order to monitor all points in the power system in real time. This provides a practical view of system parameter changes, system abnormal conditions and its stability and security information system. These developments provide valuable measurements for technical power system operators in the energy control centers. Phasor Measurement technology is an excellent solution for improving system planning, operation and energy trading in addition to enabling advanced applications in Wide Area Monitoring, Protection and Control (WAMPAC). Moreover, a virtual protection system was developed and implemented in the smart grid laboratory with integrated functionality for wide area applications. Experiments and procedures were developed in the system in order to detect the system abnormal conditions and apply proper remedies to heal the system. A design for DC microgrid was developed to integrate it to the AC system with appropriate control capability. This system represents realistic hybrid AC/DC microgrids connectivity to the AC side to study the use of such architecture in system operation to help remedy system abnormal conditions. In addition, this dissertation explored the challenges and feasibility of the implementation of real-time system analysis features in order to monitor the system security and stability measures. These indices are measured experimentally during the operation of the developed hybrid AC/DC microgrids. Furthermore, a real-time optimal power flow system was implemented to optimally manage the power sharing between AC generators and DC side resources. A study relating to real-time energy management algorithm in hybrid microgrids was performed to evaluate the effects of using energy storage resources and their use in mitigating heavy load impacts on system stability and operational security.

Exoneration or observation? Examining a novel difference between liars and truth tellers

Individual cues to deception are subtle and often missed by lay people and law enforcement alike. Linguistic statement analysis remains a potentially useful way of overcoming individual diagnostic limitations (e.g. Criteria based Content Analysis; Steller & Köhnken, 1989; Reality monitoring; Johnson & Raye, 1981; Scientific Content Analysis; Sapir, 1996). Unfortunately many of these procedures are time-consuming, require in-depth training, as well as lack empirical support and/or external validity. The current dissertation develops a novel approach to statement veracity analysis that is simple to learn, easy to administer, theoretically sound, and empirically validated. ^ Two strategies were proposed for detecting differences between liars' and truth-tellers' statements. Liars were hypothesized to strategically write statements with the goal of self-exoneration. Liars' statements were predicted to contain more first person pronouns and fewer third person pronouns. Truth-tellers were hypothesized to be motivated toward being informative and thus produce statements with fewer first person pronouns and more third person pronouns. Three studies were conducted to test this hypothesis. The first study explored the verbal patterns of exoneration and informativeness focused statements. The second study used a traditional theft paradigm to examine these verbal patterns in guilty liars and innocent truth tellers. In the third study to better match the context of a criminal investigation a cheating paradigm was used in which spontaneous lying was induced and written statements were taken. Support for the first person pronoun hypothesis was found. Limited support was found for the third person pronoun hypothesis. Results, implications, and future directions for the current research are discussed.^

Resistance performances: (Re)constructing spaces of resistance and contention in the 2010-2011 University of Puerto Rico student movement

On the night of April 20, 2010, a group of students from the University of Puerto Rico (UPR), Río Piedras campus, met to organize an indefinite strike that quickly broadened into a defense of accessible public higher education of excellence as a fundamental right and not a privilege. Although the history of student activism in the UPR can be traced back to the early 1900s, the 2010-2011 strike will be remembered for the student activists’ use of new media technologies as resources that rapidly prompted and aided the numerous protests. ^ This activist research entailed a critical ethnography and a critical discourse analysis (CDA) of traditional and alternative media coverage and treatment during the 2010 -2011 UPR student strike. I examined the use of the 2010-2011 UPR student activists’ resistance performances in constructing local, corporeal, and virtual spaces of resistance and contention during their movement. In particular, I analyzed the different tactics and strategies of resistance or repertoire of collective actions that student activists used (e.g. new media technologies) to frame their collective identities via alternative news media’s (re)presentation of the strike, while juxtaposing the university administration’s counter-resistance performances in counter-framing the student activists’ collective identity via traditional news media representations of the strike. I illustrated how both traditional and alternative media (re)presentations of student activism developed, maintained, and/or modified students activists’ collective identities. ^ As such, the UPR student activism’s success should not be measured by the sum of demands granted, but by the sense of community achieved and the establishment of networks that continue to create resistance and change. These networks add to the debate surrounding Internet activism and its impact on student activism. Ultimately, the results of this study highlight the important role student movements have had in challenging different types of government policies and raising awareness of the importance of an accessible public higher education of excellence.^