People with severe visual impairments cannot drive, so they often rely on public transit. The usability of the public transit system is, therefore, of crucial importance to blind people. One major challenge blind people experience when using public transportation is finding the exact location of bus stops. We have developed StopFinder, a system that uses crowdsourcing to provide information about non-visual landmarks around bus stops to enable blind people to find them more easily when navigating with a cane or a guide dog. It is developed in iPhone, and blind people can use our system using the access technology called VoiceOver, the built-in feature of iPhone that enables them to hear the information in the screen and navigate screen through simple hand gestures like single or double finger flicks, taps etc. The crowdsourced information includes which street/avenue has the bus stop, which direction to walk to reach the bus stop once you arrive at the intersection and what to expect once you arrive at the bus stop like the presence of shelters, garbage cans, benches etc. Since we are using crowsourcing for getting information, we provide an option to rate the entry. In addition to accessing and rating information about a bus stop, blind people can also contribute information through a non-graphical interface. The interface consists of mostly multiple-choice questions that are convenient to fill in a short time while waiting for a bus using VoiceOver. Since one of our primary foci has been the ease of using Stopfinder, we conducted interviews with blind people that informed the design of the application.

OneBusAway is an application providing real-time arrival information to tens of thousands of transit riders daily. As a system built on providing reliable information, one of the cornerstones of OneBusAway is threatened when it does not provide accurate information to its users. Our surveys and interviews of current OneBusAway users confirmed that inconsistencies in the application have a significant impact on riders’ transit experience by making them miss their bus and lose trust in the application. In addition, users of the application have limited options for reporting issues with inaccurate information and lack the means to easily receive targeted feedback about their reports. Furthermore, reports received by OneBusAway are not currently categorized, verified for validity, or sent to one central repository, leading to a significant amount of manual work for OneBusAway developers.To address this problem, we designed an issue-reporting system that relies on a network of users to submit, approve, and resolve issues encountered in OneBusAway. Using OneBusAway to establish communication between transit riders and agencies, our system will direct issue reports to the source for resolution and provide feedback to users when the problems are resolved. Our application will empower users with the tools to get actively involved in their transit community and improve the transit experience.

Understanding stem cell maintenance is crucial for delineating conditions such as tissue loss, aging, and cancer. Using the Drosophila female germ-line stem cell (GSC) model to observe stem cells in vivo, several extrinsic and intrinsic factors have been demonstrated to regulate maintenance of Drosophila GSCs; they have also been found to be conserved in mammalian systems. The search is on for novel regulatory factors of stem cell maintenance with the hope of extending our understanding to stem cells in mammalian systems. My project involves the characterization of the molecular function of Pineapple eye gene (Pie), a novel regulator of GSC maintenance. Through a loss-of-function screen in GSCs, it has been demonstrated that mutations of pie result in GSC maintenance failure. The amino acid sequence of pie revealed that it contains ring-domains suggesting possible E3 ubiquitin ligase function. Such proteins are key components of the ubiquitination pathway, which are involved in protein tagging and degradation. To test pie’s function as an E3 ligase, I am using a novel assay that employs the fact that bacteria do not have endogenous ubiquitination pathway and therefore utilizes Escheria coli as an in vivo system to express the components of the ubiquitination pathway and detect the formation of ubiquitin chains, a key indicator of E3 Ligase activity. I have demonstrated that the expression of pie’s ring-domains without a substrate is not sufficient for the detection of ubiquitin chains. I will now test whether the full length pie is necessary for proper ubiquitination. Further, I will also test whether pie’s functional domain needs a substrate in order to function effectively. Successful characterization of pie can reveal new pathways to target for conditions involving stem cell maintenance.

The lymphatic system is essential to fluid and cell transport, immune function, and tumor metastasis. Lymph drains from body extremities into lymph nodes, via lymphatic vessels, to present antigens to lymphocytes. This can result in an immune response. The existence of tumor cells in lymph nodes is a sign that cellular metastasis has occurred from the primary tumor. I am studying lymphangiogenesis, a process in which lymphatic vessels and sinuses grow and dilate in response to antigens or tumors, thus increasing the lymph flow and capacity to transport tumor cells in lymph nodes. Recently an antibody, 10.1.1, has been discovered to recognize an antigen that is selectively and highly expressed in lymphatic endothelium. The 10.1.1 antibody specifically induces lymph node lymphangiogenesis. This binding also induces proliferation of an unknown cell type in the lymph node. In comparison to the 10.1.1 antibody, injecting a nonspecific antibody control has no effect on lymphatic sinus growth. I am therefore studying how the 10.1.1 antibody rapidly induces lymphatic sinus growth, as well as what cell types contribute to making the new sinuses. I am using the technique of immunostaining to study the effects of the 10.1.1 antibody. By taking a frozen slice of lymphatic tissue and staining it with various antibodies to detect proliferating cells and their cell type, I can identify the specific kinds of cells that are forming into lymphatic sinuses. An understanding of how these lymphatic sinuses grow could help generate therapeutic strategies for manipulation of the lymphatic or immune responses. By inhibiting sinus growth and thus limiting lymph flow, it could be possible to prevent the metastasis of cancer.