410 research outputs found
"Extension Field Specialists": Believable Label or Oxymoron?
Includes Poster and accompanying Poster PaperTeaching/Communication/Extension/Profession,
Microengineering Aligned Collagen Substrates In Microfluidic Systems
Cells in vivo are surrounded by a fibrous matrix of proteins and macromolecules called the extracellular matrix (ECM), of which type I collagen is the major constituent. During tissue development or cell-matrix interactions, collagen fibers organize into aligned domains with defined degrees of alignment and directionality. Aligned fibers guide stem cell differentiation and influence cell-cell communication and cell motility. In the tumor microenvironment, aligned fibers guide tumor cell invasion and have been linked to poor patient outcomes. Since fiber alignment instructs cell behavior in vivo, there is a need for in vitro models to replicate fiber alignment and thus provide a relevant microenvironment for cells. Microfluidic systems have been established as advanced cell culture platforms to provide precise control over soluble factor concentration, cell patterning, and fluid flow. However, controlling the fiber alignment of a 3D material within them has remained a challenge. This work addresses existing technological challenges to integrate 3D collagen matrices with aligned fibers into microfluidic platforms. To do so, this work i) Demonstrates for the first time that extensional flows can align 3D collagen matrices (250 µm thick) in a microchannel, ii) Develops modular microfluidic platforms with capabilities to directly access and perfuse 3D collagen, and iii) Develops biofabrication capabilities to create interfaces between different ECM materials in 3D, and create tissue barriers using ultrathin nanomembranes. It is anticipated that the novel ECM microengineering capabilities and approach to integrating the engineered matrices into microfluidic devices will provide a path to develop tissue-specific in vitro models with engineered matrices
Efficient Template-Based Nanomanufacturing of Carbon Nanotube Arrays for Cell Applications
Carbon nanotube arrays have been found to be highly effective at carrying out intracellular delivery of cargo at high efficiencies while ensuring cell viability. Template based chemical vapor deposition is a commonly used process to fabricate these arrays. However, current etching methods used to expose carbon nanotubes from templates are expensive and time consuming. The high cost and time-consuming processes currently required to fabricate such arrays are factors which limit the commercialization of this technology and inhibit scope for larger research programs. In this thesis, alternative nanofabrication methods were explored with the aim of making the fabrication of CNT arrays cost effective and efficient. Mechanical polishing coupled with wet chemical etching is shown as a feasible alternative option to dry etching. The effects of process variables on physical properties of CNT arrays have been studied and quantified in order to demonstrate control over the process. Scanning Electron Microscopy has been used to qualitatively understand the differences between CNT arrays fabricated using dry etching and the alternative process. Cell culture has been demonstrated on the CNT arrays and the potential to use 3D printing to fabricate a nanofluidic device is also demonstrated. The alternative process can save etching time by 97% while maintaining a similar level of control over the process. This study, therefore, opens the path to quicker production of CNT arrays at low cost for biomedical use
Crowdsourcing Rural Data Collection
The rise of geospatial information on popular websites and its comparative lack in rural areas prompted the pilot project described here to apply crowdsourcing techniques to community mapping. The 3-month project yielded many valuable lessons to apply to future endeavors, but did not yield enough point-of-interest (POI) data to merit an analysis of its accuracy. Results were disappointing in that few POIs were collected, despite participants\u27 initial enthusiasm and hours of training. Key questions for the future are the following. Is it feasible to sustain volunteer-based community mapping efforts in rural areas? And, if so, what kind of incentives should be offered
Strategies for prevention of road traffic injuries (RTIs) in Pakistan: situational analysis.
Road traffic injuries (RTIs) are one of the leading causes of death among productive age group. Using systems approach framework (SAF), current preventive strategies for RTI control were reviewed in Pakistan. A review of the literature was done using four international search engines. Only ten studies on preventive strategies for RTI stemming from Pakistan were found. The first Road Traffic Injuries Research Network (RTIRN) surveillance system for road traffic injuries was established in urban city (Karachi) in Pakistan has shown promise for injury control and should be scaled up to other cities. Enforcement of traffic laws on seat-belt and helmet wearing is poor. National Highway and Motorway Police Ordinance (2000) was one of the few legislative measure so far taken in Pakistan. Using SAF, efforts are required to implement interventions targeting human, vehicle design and also making environment safer for road users
THE RELATIONSHIP BETWEEN CORRUPTION AND ECONOMIC GROWTH IN PAKISTAN — LOOKING BEYOUND THE INCUMBENT
Corruption has opaque significant consideration for researchers during the last few decades due to its effect on economic growth. This study examines the relationship between corruption and economic growth in Pakistan, covering the period from 1985 to 2010. Stationarity of the variables was checked through unit root test and then apply multiple regression technique. The results shows that government expenditures, education expenditures and population growth has a positive impact on per capita GDP, however, domestic investment and corruption has a negative impact on per capita income in Pakistan. It implies that corruption is a major factor impeding economic development. Corruption hampers economic growth, disproportionately burdens the poor and undermines the effectiveness of investment and aid
Usability Studies In Virtual And Traditional Computer Aided Design Environments For Navigation
A usability study was used to measure user performance and user preferences for a CAVETM immersive stereoscopic virtual environment with wand interfaces compared directly with a workstation non-stereoscopic traditional CAD interface with keyboard and mouse. In both the CAVETM and the adaptable technology environments, crystal eye glasses are used to produce a stereoscopic view. An ascension flock of birds tracking system is used for tracking the user’s head and wand pointing device positions in 3D space. It is argued that with these immersive technologies, including the use of gestures and hand movements, a more natural interface in immersive virtual environments is possible. Such an interface allows a more rapid and efficient set of actions to recognize geometry, interaction within a spatial environment, the ability to find errors, and navigate through a virtual environment. The wand interface provides a significantly improved means of interaction. This study quantitatively measures the differences in interaction when compared with traditional human computer interfaces. This paper provides analysis via usability study methods for navigation termed as Benchmark 1. During testing, testers are given some time to “play around” with the CAVETM environment for familiarity before undertaking a specific exercise. The testers are then instructed regarding tasks to be completed, and are asked to work quickly without sacrificing accuracy. The research team timed each task, and recorded activity on evaluation sheets for Navigation Test. At the completion of the testing scenario involving navigation, the subject/testers were given a survey document and asked to respond by checking boxes to communicate their subjective opinions
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