Nanoscience and Nanotechnology Commons^™

Forisome Performance In Artificial Sieve Tubes, Michael Knoblauch, Mike Stubenrauch, Aart J.E. Van Bel, Winfried S. Peters

Winfried S. Peters

Social Networks And Web2.0 Among Youth: Lessons For Pacific Island Nations, Deogratias Harorimana Sr

Dr Deogratias Harorimana

This study is on social networks and web2 among youths and the lessons for Pacific Island nation. This study defines commonly used social networking sites used by the Pacific youths, average time spent, reasons behind the use of social networking sites and how social networking sites can be used as a development tool for Pacific Island nation. It was found that the popularity of social networking amongst youths in Pacific Island Countries is fast growing, increasing more than three folds year on year in the last 3years. Social Networks are a vital part of life for PIC youths, where, now …

Using The Case Study Methodology In Teaching, Deogratias Harorimana Mr

Dr Deogratias Harorimana

This paper reviews the Why, How, to use the Case Study Methods in MBA teaching. The Presentation was prepared for and delivered as part of MBA students induction Programme in the Graduate School of Business.

The Gatekeeper And The Knowledge Environment-Who They Are, How They Work Empirical Evidences From High-Tech Manufacturing And R&D Firms, Deogratias Harorimana

Dr Deogratias Harorimana

Purpose of the Study: The purpose of this study was to critically study the role of the Knowledge Gatekeeper within the manufacturing and high tech selected case studies and by explaining who they are, how they work and identify and analyse the barriers to knowledge creation and knowledge sharing. Methodology: The research was guided by an inductive approach with a multiple case study strategy. Research instruments included a questionnaire and interviews from respectively 105 and 40 respondents. Findings: In the African Manufacturing context, and in absence of sophisticated technologies and highly qualified personnel, technical knowledge can be obtained from organizational …

Review Of Economics Of Manamagement Information Systems, Deogratias Harorimana Sr

Dr Deogratias Harorimana

“Information technology is the "digital nervous system" of any business.” (Bill Gates, Chairman, Microsoft Corporation, 1997)

The way business is conducted in this era is phenomenal. Almost everything is a “click” away. The customers are satisfied, businesses are satisfied, Government is satisfied and the entire globe is gratified by the work of information technology (IT). This research discloses the several returns and shortcomings of IT, and how businesses use IT to realize their strategic goals.

The report presents discussion on two organisations, Dell Computer Corporation and Sydney Waters, which had a prosperous and disastrous implementation of IT systems respectively. The …

Using Mis To Deliver Essential Services:Case Of Healthcare Provision Support In Fiji, Deogratias Harorimana Sr

Dr Deogratias Harorimana

In comparison to other Pacific Island countries, Fiji’s health system is the most developed amongst Pacific Island countries (UNDP 2006) and has undergone significant change in the last decade. From 1999 – 2009, AusAid, a major donor to Fiji’s health system, has supported two stage health sector improvement programs. The first stage (1999 - 2003) was a management reform program designed to improve decision making by supporting a new model of decentralized management. The second phase (2004 – 2009) looked at improving governance, health systems performance, clinical outcomes and supported public health and infrastructure initiatives at the divisional level (WHO …

Impact Of Crm Systems On Organisational Performance: A Case Study Of Anz Bank, Deogratias Harorimana Sr

Dr Deogratias Harorimana

This paper reports case study results analysis of the ANZ Bank in the Pacific Region. The case study results show that ANZ has a well-established CRM system supporting its marketing and sales activities, but equally the results indicate mixed scenarios. A positive relationship between CRM to performance was established. That is, it has a positive contribution to the bank’s performance, both financial and non-financial. There is also negative feedback on the bank’s CRM system which illustrates that CRM system can also have negative consequences. CRM success is questionable from a stand-alone perspective. Although there are encouraging results from the use …

Cell Permeabilization And Inhibition Of Voltage-Gated Ca²+ And Na+ Channel Currents By Nanosecond Pulsed Electric Fields, Vasyl Nesin, Angela M. Bowman, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Previous studies have found that nanosecond pulsed electric field (nsPEF) exposure causes long-term permeabilization of the cell plasma membrane. In this study, we utilized the whole-cell patch-clamp method to study the nsPEF effect on currents of voltage-gated (VG) Ca²⁺ and Na⁺ channels (I_Ca and I_Na) in cultured GH3 and NG108 cells. We found that a single 300 or 600 ns pulse at or above 1.5-2 kV/cm caused prolonged inhibition of I_Ca and I_Na. Concurrently, nsPEF increased a non-inactivating leak current (I_leak), presumably due to the formation of nanoelectropores or larger …

Structural Basis Of Substrate Recognition In Thimet Oligopeptidase And Development Of Nanoparticles For Therapeutic Enzyme Delivery, Jonathan Mark Wagner

Theses and Dissertations--Molecular and Cellular Biochemistry

Neuropeptidases are responsible for degradation of signaling peptides in the central nervous system and periphery. Some neuropeptidases have also been shown to play a role as part of the cell’s hydrolytic machinery responsible for breaking down proteins and peptides into amino acids, and these enzymes therefore influence small peptide availability for antigen presentation. A better understanding of how neuropeptidases recognize their substrates could lead to therapeutics that modulate the activity of these important enzymes. Alternatively, re-engineering these enzymes to selectively hydrolyze undesirable peptides could make them attractive as therapeutics themselves. A key question in understanding the activity of these enzymes …

Virus Capsids As Nanoscale Delivery Vessels Of Photoactive Compounds For Site-Specific Photodynamic Therapy, Brian Alexander Cohen

Legacy Theses & Dissertations (2009 - 2024)

The research presented in this work details the use of a viral capsid as an addressable delivery vessel of photoactive compounds for use in photodynamic therapy. Photodynamic therapy is a treatment that involves the interaction of light with a photosensitizing molecule to create singlet oxygen, a reactive oxygen species. Overproduction of singlet oxygen in cells can cause oxidative damage leading to cytotoxicity and eventually cell death. Challenges with the current generation of FDA-approved photosensitizers for photodynamic therapy primarily stem from their lack of tissue specificity. This work describes the packaging of photoactive cationic porphyrins inside the MS2 bacteriophage capsid, followed …

Micropatterned Electrospun Nanofibrous Substrates As Scaffolds For Engineered Salivary Glands, David Alexander Soscia

Legacy Theses & Dissertations (2009 - 2024)

The salivary gland is a complex organ exhibiting a branching, 3-dimensional structure made up of acinar (saliva-producing), and ductal (saliva transporting and modifying) epithelial cells. The high surface area of the gland allows it to efficiently provide the mouth with saliva, maintaining oral cleanliness and comfort. Salivary gland hypofunction, a significant clinical problem often caused by the autoimmune disease Sjögren's syndrome or head and neck radiation for cancer patients, affects millions of Americans and is characterized by a loss of function of salivary gland acinar cells. Chronic xerostomia, or dry mouth, arises as a result of salivary gland hypofunction and …

Investigations Of Oxidative Stress Effects And Their Mechanisms In Rat Brain After Systemic Administration Of Ceria Engineered Nanomaterials, Sarita S. Hardas

Theses and Dissertations--Chemistry

Advancing applications of engineered nanomaterials (ENM) in various fields create the opportunity for intended (e.g. drug and gene delivery) or unintended (e.g. occupational and environmental) exposure to ENM. However, the knowledge of ENM-toxicity is lagging behind their application development. Understanding the ENM hazard can help us to avoid potential human health problems associated with ENM applications as well as to increase their public acceptance. Ceria (cerium [Ce] oxide) ENM have many current and potential commercial applications. Beyond the traditional use of ceria as an abrasive, the scope of ceria ENM applications now extends into fuel cell manufacturing, diesel fuel additives …

Microfluidic Separation Of Live And Dead Yeast Cells Using Reservoir-Based Dielectrophoresis, Saurin Patel, Daniel Showers, Pallavi Vedantam, Tzuen-Rong Tzeng, Shizhi Qian, Xiangchun Xuan

Mechanical & Aerospace Engineering Faculty Publications

Separating live and dead cells is critical to the diagnosis of early stage diseases and to the efficacy test of drug screening, etc. This work demonstrates a novel microfluidic approach to dielectrophoretic separation of yeast cells by viability. It exploits the cell dielectrophoresis that is induced by the inherent electric field gradient at the reservoir-microchannel junction to selectively trap dead yeast cells and continuously separate them from live ones right inside the reservoir. This approach is therefore termed reservoir-based dielectrophoresis (rDEP). It has unique advantages as compared to existing dielectrophoretic approaches such as the occupation of zero channel space and …

A Review Of International Best Practice In E-Governmentsome Lessons For New Adopters, Deogratias Harorimana Sr

Dr Deogratias Harorimana

Efficient bureaucratic processes as essential to attract and retain investment, as well as promote SME growth. The e_Gov is one of many ways emerging economies have used to streamline public service delivery and create a freindly and conducive atmosphere for business -both MNC and SMEs. This presentation provide an overview of some of the World's most recent case examples on the successful design-plan-implementation of eGov to build a strong basis to attract investment and deliver seamless essential services to Citizens.

A Critical Review Of The Effectiveness Of Fiscal And Monetary Policies In The Pacific Island Countries (Pics) Between 1990-2010, Deogratias Harorimana Mr

Dr Deogratias Harorimana

The purpose of this paper is to critically assess the effectiveness of Fiscal and Monetary Policies in the South Pacific Island Countries. The paper tracks down the economic growth for the last 20 years between 1990-2010, and drawing from key fiscal and monetary policies in place during the time under consideration, as well as specific interventions in the region, we find that: 1) While the South Pacific Island Countries (SPICs) particularly the six major economies (Solomon Islands, Fiji, Vanuatu, PNG, Samoa, Tonga) pursued fiscal and monetary policies for promoting growth and diversification of their economies, their fiscal policies relied heavily …

Issues In Human Capital Development : Lessons For Public Administration And Governance, Deogratias Harorimana Mr

Dr Deogratias Harorimana

With few minerals or other natural resources, Rwanda believes that she can still achieve her ambitions by investing in human capital - her unique resource. If this ambition can be achieved, then is this the next role model for international development? We used a case study design and analysis methods to examine development models used elsewhere in recent decades, using both qualitative and quantitative data on Rwanda to establish the comparative advantages in relation to Singapore’s economic development model. The implications for international development are that (1) an effective human capital development strategy should be inclusive enough to respond to …

Exploring Bacterial Nanowires: From Properties To Functions And Implications, Kar Man Leung

Electronic Thesis and Dissertation Repository

The discovery of electrically conductive bacterial nanowires from a broad range of microbes provides completely new insights into microbial physiology. Shewanella oneidensis strain MR-1, a dissimilatory metal-reducing bacterium, produces extracellular bacterial nanowires up to tens of micrometers long, with a lateral dimension of ~10 nm. The Shewanella bacterial nanowires are efficient electrical conductors as revealed by scanning probe techniques such as CP-AFM and STM.

Direct electrical transport measurements along Shewanella nanowires reveal a measured nanowire resistivity on the order of 1 Ω∙cm. With electron transport rates up to 10⁹/s at 100 mV, bacterial nanowires can serve as a …

Toxicity Of Cdse Nanoparticles In Caco-2 Cell Cultures, Lin Wang, Dattatri K. Nagesha, Selvapraba Selvarasah, Mehmet R. Dokmeci, Rebecca L. Carrier

Dattatri K. Nagesha

BackgroundPotential routes of nanomaterial exposure include inhalation, dermal contact, and ingestion. Toxicology of inhalation of ultra-fine particles has been extensively studied; however, risks of nanomaterial exposure via ingestion are currently almost unknown. Using enterocyte-like Caco-2 cells as a small intestine epithelial model, the possible toxicity of CdSe quantum dot (QD) exposure via ingestion was investigated. Effect of simulated gastric fluid treatment on CdSe QD cytotoxicity was also studied. ResultsCommercially available CdSe QDs, which have a ZnS shell and poly-ethylene glycol (PEG) coating, and in-house prepared surfactant coated CdSe QDs were dosed to Caco-2 cells. Cell viability and attachment were studied …

Toxicity Of Cdse Nanoparticles In Caco-2 Cell Cultures, Lin Wang, Dattatri K. Nagesha, Selvapraba Selvarasah, Mehmet R. Dokmeci, Rebecca L. Carrier

Rebecca L. Carrier

BackgroundPotential routes of nanomaterial exposure include inhalation, dermal contact, and ingestion. Toxicology of inhalation of ultra-fine particles has been extensively studied; however, risks of nanomaterial exposure via ingestion are currently almost unknown. Using enterocyte-like Caco-2 cells as a small intestine epithelial model, the possible toxicity of CdSe quantum dot (QD) exposure via ingestion was investigated. Effect of simulated gastric fluid treatment on CdSe QD cytotoxicity was also studied. ResultsCommercially available CdSe QDs, which have a ZnS shell and poly-ethylene glycol (PEG) coating, and in-house prepared surfactant coated CdSe QDs were dosed to Caco-2 cells. Cell viability and attachment were studied …

Toxicity Of Cdse Nanoparticles In Caco-2 Cell Cultures, Lin Wang, Dattatri Nagesha, Selvapraba Selvarasah, Mehmet Dokmeci, Rebecca Carrier

Mehmet R. Dokmeci

Background
Potential routes of nanomaterial exposure include inhalation, dermal contact, and ingestion. Toxicology of inhalation of ultra-fine particles has been extensively studied; however, risks of nanomaterial exposure via ingestion are currently almost unknown. Using enterocyte-like Caco-2 cells as a small intestine epithelial model, the possible toxicity of CdSe quantum dot (QD) exposure via ingestion was investigated. Effect of simulated gastric fluid treatment on CdSe QD cytotoxicity was also studied.

Results
Commercially available CdSe QDs, which have a ZnS shell and poly-ethylene glycol (PEG) coating, and in-house prepared surfactant coated CdSe QDs were dosed to Caco-2 cells. Cell viability and attachment …

Artificial And Natural Nucleic Acid Self Assembling Systems, Marcus Wood

Wayne State University Dissertations

Nucleic acids are good candidates for nanomachine construction. They participate in all the processes of life, and so can function as structural building blocks and dynamic catalysts. However, to use nucleic acids as nanomachines, a better understanding of their material properties, how to design structures using them, and their dynamics is needed. We have tried to address these issues, in a small way, with nucleic acid force field development, an attempt at nanostructural design and synthesis using DNA, and a study of the RNA/protein regulatory dynamics of the tryptophan regulatory attenuation protein.

The Formation And Distribution Of Hippocampal Synapses On Patterned Neuronal Networks, Natalie Michelle Dowell-Mesfin

Legacy Theses & Dissertations (2009 - 2024)

ABSTRACT

A Cell Electrofusion Microfluidic Device Integrated With 3d Thin-Film Microelectrode Arrays, Ning Hu, Jun Yang, Shizhi Qian, Sang W. Joo, Xiaolin Zheng

Mechanical & Aerospace Engineering Faculty Publications

A microfluidic device integrated with 3D thin film microelectrode arrays wrapped around serpentine-shaped microchannel walls has been designed, fabricated and tested for cell electrofusion. Each microelectrode array has 1015 discrete microelectrodes patterned on each side wall, and the adjacent microelectrodes are separated by coplanar dielectric channel wall. The device was tested to electrofuse K562 cells under a relatively low voltage. Under an AC electric field applied between the pair of the microelectrode arrays, cells are paired at the edge of each discrete microelectrode due to the induced positive dielectrophoresis. Subsequently, electric pulse signals are sequentially applied between the microelectrode arrays …

Closing The Gap Between The Industry And Higher Education Institutions- Case Examples From East African Region, Deogratias Harorimana Mr

Dr Deogratias Harorimana

Much complained about is the quality of graduates Universities put on the labour market. Less talked about however is why knowledge institutions seems to be bad knowledge managers. In this presentation I argue that DIRECT collaborative relationship between Industry,Governments and Higher Education Institutions is a per-requisite.Good relationship is key to building such a successful knowledge transfer strategies between Industries and Educational and Research Institutions. This paper explores what makes a good Knowledge Transfer Partnership Strategy and highlights some key lessons for businesses, Universities and Government bodies. This paper was a Key note presentation to the Annual International Conference on Building …

Negative Dielectrophoretic Capture Of Bacterial Spores In Food Matrices, Mehti Koklu, Seungkyung Park, Suresh D. Pillai, Ali Beskok

Mechanical & Aerospace Engineering Faculty Publications

A microfluidic device with planar square electrodes is developed for capturing particles from high conductivity media using negative dielectrophoresis (n-DEP). Specifically, Bacillus subtilis and Clostridium sporogenes spores, and polystyrene particles are tested in NaCl solution (0.05 and 0.225 S/m), apple juice (0.225 S/m), and milk (0.525 S/m). Depending on the conductivity of the medium, the Joule heating produces electrothermal flow (ETF), which continuously circulates and transports the particles to the DEP capture sites. Combination of the ETF and n-DEP results in different particle capture efficiencies as a function of the conductivity. Utilizing 20 μm height DEP chambers, “almost complete” and …

Münch, Morphology, Microfluidics – Our Structural Problem With The Phloem [Review Article], Michael Knoblauch, Winfried S. Peters

Winfried S. Peters

Rwanda National Customer Satisfaction Survey: Results And Conclusions, Deogratias Harorimana

Dr Deogratias Harorimana

It can be said that development practice requires more than financial and manpower inputs. Rwanda, in 1994 suffered a Genocide. The Society,collectively and under the leadership of His Excellence Paul Kagame the current elected President of Rwanda came together and designed strategies that would propel Rwanda to a Middle-Income, Private Sector Led Economy by the Year 2020.

In 2009, a client seating in one of the Hotels in a Suburb of Remera, in Kigali City, complained about poor service delivery he was experiencing from the waitress staff.Using his Blackberry message, the client forwarded an email to some of the RDB …

Enterprise Development Policies And Capacity-Building In Science, Technology And Innovation (Sti)-Response To The Issue Note, Deogratias Harorimana

Dr Deogratias Harorimana

Enterprise Development, Investment and Business Climate are all important for economic growth. But what policies, strategies are needed to make economic growth a reality. The author has followed one of the World's fastest reformer and emerging nation in the Heart of Africa-Rwanda. The paper shares lessons and practical aspects related to building an entrepreneurial population, and building a government which is a facilitator of business climate

Survey Report On Training And Spending On Customer Care Services, Deogratias Harorimana Sr

Dr Deogratias Harorimana

In a bid to promote and develop good customer care service in various sectors of Rwandan economy, a survey was conducted to assess progress and trends on customer service capacity building. Although shortcomings are there, there have been efforts and registered trends across the country on service delivery front. Investment in Capacity Building IS happening in certain sectors but this is unevenly distributed. In 2008 companies had started recognizing the significance of good service and cultivate a good working environment and training. From 2009, there was a decline in investment in capacity building in front office and key service delivery …

Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, Ye Ai, Shizhi Qian, Sheng Liu, Sang W. Joo

Mechanical & Aerospace Engineering Faculty Publications

Experiments show that particles smaller than the throat size of converging-diverging microchannels can sometimes be trapped near the throat. This critical phenomenon is associated with the negative dc dielectrophoresis arising from nonuniform electric fields in the microchannels. A finite-element model, accounting for the particle-fluid-electric field interactions, is employed to investigate the conditions for this dielectrophoretic (DEP) choking in a converging-diverging microchannel for the first time. It is shown quantitatively that the DEP choking occurs for high nonuniformity of electric fields, high ratio of particle size to throat size, and high ratio of particle's zeta potential to that of microchannel. © …