Use of manual adaptive remeshing in the mechanical modeling of an intraneural ganglion cyst

Intraneural Ganglion Cysts expand within in a nerve, causing neurological deficits in afflicted patients. Modeling the propagation of these cysts, originating in the articular branch and then expanding radially outward, will help prove articular theory, and ultimately allow for more purposeful treatment of this condition. In Finite Element Analysis, traditional Lagrangian meshing methods fail to model the excessive deformation that occurs in the propagation of these cysts. This report explores the method of manual adaptive remeshing as a method to allow for the use of Lagrangian meshing, while circumventing the severe mesh distortions typical of using a Lagrangian mesh with a large deformation. Manual adaptive remeshing is the process of remeshing a deformed meshed part and then reapplying loads in order to achieve a larger deformation than a single mesh can achieve without excessive distortion. The methods of manual adaptive remeshing described in this Master’s Report are sufficient in modeling large deformations

How Do Tor Users Interact With Onion Services?

Onion services are anonymous network services that are exposed over the Tor network. In contrast to conventional Internet services, onion services are private, generally not indexed by search engines, and use self-certifying domain names that are long and difficult for humans to read. In this paper, we study how people perceive, understand, and use onion services based on data from 17 semi-structured interviews and an online survey of 517 users. We find that users have an incomplete mental model of onion services, use these services for anonymity and have varying trust in onion services in general. Users also have difficulty discovering and tracking onion sites and authenticating them. Finally, users want technical improvements to onion services and better information on how to use them. Our findings suggest various improvements for the security and usability of Tor onion services, including ways to automatically detect phishing of onion services, more clear security indicators, and ways to manage onion domain names that are difficult to remember.Comment: Appeared in USENIX Security Symposium 201

Navigating the Self in Diverse Work Contexts

Navigating the self is critical for working in a diverse world, in which different identities interact in social space. This chapter presents five theoretical perspectives on how individuals navigate the self in diverse organizational contexts—social identity, critical identity, (role) identity, narrative-as-identity, and identity work. We review these five prominent theoretical perspectives on identity processes in diverse contexts to explicate various ways in which individuals actively participate in the co-construction of their identities in diverse contexts. As a next step in research, identity, diversity, and relationship scholars are encouraged to inquire into the generativity of proposed tactics for navigating the self in order to identify pathways for cultivating more positive identities in diverse work settings. The examination of positive relational identities is considered a promising path for further inquiry in this domain

Perceived stress and emotional social support among women who are denied or receive abortions in the United States: a prospective cohort study.

BackgroundExamining women's stress and social support following denial and receipt of abortion furthers understanding of the effects of unwanted childbearing and abortion on women's well-being. This study investigated perceived stress and emotional social support over time among women who were denied wanted abortions and who received abortions, and compared outcomes between the groups.MethodsThe Turnaway Study is a prospective cohort study of women who sought abortions at 30 abortion facilities across the United States, and follows women via semiannual phone interviews for five years. Participants include 956 English or Spanish speaking women aged 15 and over who sought abortions between 2008 and 2010 and whose gestation in pregnancy fit one of three groups: women who presented up to three weeks beyond a facility's gestational age limit and were denied an abortion; women presenting within two weeks below the limit who received an abortion; and women who received a first trimester abortion. The outcomes were modified versions of the Perceived Stress Scale and the Multidimensional Scale of Perceived Social Support. Longitudinal mixed effects models were used to assess differences in outcomes between study groups over 30 months.ResultsWomen denied abortions initially had higher perceived stress than women receiving abortions near gestational age limits (1.0 unit difference on 0-16 scale, P = 0.003). Women receiving first-trimester abortions initially had lower perceived stress than women receiving abortions near gestational age limits (0.6 difference, P = 0.045). By six months, all groups' levels of perceived stress were similar, and levels remained similar through 30 months. Emotional social support scores did not differ among women receiving abortions near gestational limits versus women denied abortions or women having first trimester abortions initially or over time.ConclusionsSoon after being denied abortions, women experienced higher perceived stress than women who received abortions. The study found no longer-term differences in perceived stress or emotional social support between women who received versus were denied abortions

Effect of Uveal Melanocytes on Choroidal Morphology in Rhesus Macaques and Humans on Enhanced-Depth Imaging Optical Coherence Tomography.

PurposeTo compare cross-sectional choroidal morphology in rhesus macaque and human eyes using enhanced-depth imaging optical coherence tomography (EDI-OCT) and histologic analysis.MethodsEnhanced-depth imaging-OCT images from 25 rhesus macaque and 30 human eyes were evaluated for choriocapillaris and choroidal-scleral junction (CSJ) visibility in the central macula based on OCT reflectivity profiles, and compared with age-matched histologic sections. Semiautomated segmentation of the choriocapillaris and CSJ was used to measure choriocapillary and choroidal thickness, respectively. Multivariate regression was performed to determine the association of age, refractive error, and race with choriocapillaris and CSJ visibility.ResultsRhesus macaques exhibit a distinct hyporeflective choriocapillaris layer on EDI-OCT, while the CSJ cannot be visualized. In contrast, humans show variable reflectivities of the choriocapillaris, with a distinct CSJ seen in many subjects. Histologic sections demonstrate large, darkly pigmented melanocytes that are densely distributed in the macaque choroid, while melanocytes in humans are smaller, less pigmented, and variably distributed. Optical coherence tomography reflectivity patterns of the choroid appear to correspond to the density, size, and pigmentation of choroidal melanocytes. Mean choriocapillary thickness was similar between the two species (19.3 ± 3.4 vs. 19.8 ± 3.4 μm, P = 0.615), but choroidal thickness may be lower in macaques than in humans (191.2 ± 43.0 vs. 266.8 ± 78.0 μm, P < 0.001). Racial differences in uveal pigmentation also appear to affect the visibility of the choriocapillaris and CSJ on EDI-OCT.ConclusionsPigmented uveal melanocytes affect choroidal morphology on EDI-OCT in rhesus macaque and human eyes. Racial differences in pigmentation may affect choriocapillaris and CSJ visibility, and may influence the accuracy of choroidal thickness measurements

Out of the Box? How Managing a subordinate\u27s Multiple Identities Affects the Quality of a Manager-Subordinate Relationship

Positive manager-subordinate relationships are invaluable to organizations because they enable positive employee attitudes, citizenship behaviors, task performance, and more effective organizations. Yet extant theory provides a limited perspective on the factors that create these types of relationships. We highlight the important role subordinates also play in affecting the resource pool and propose that a subordinate’s multiple identities can provide him or her with access to knowledge and social capital resources that can be utilized for work-based tasks and activities. A manager and a subordinate may prefer similar or different strategies for managing the subordinate’s multiple identities, however, which can affect resource utilization and the quality of the manager-subordinate relationship. Our variance model summarizes our predictions about the effect of managers’ and subordinates’ strategy choices on the quality of manager-subordinate relationships. In doing so we integrate three divergent relational theories (leader-member exchange theory, relational-cultural theory, and a positive organizational scholarship perspective on positive relationships at work) and offer new insights on the quality of manager-subordinate relationships

Development of tools for in situ hybridization in human embryonic stem cells

Abstract only availableOur laboratory uses human embryonic stem cells (hESC) to understand how embryonic cells differentiate into the cells of the placenta. The long term goal of my research is to develop in situ hybridization methods and use them to determine where genes are being expressed within differentiating hESC colonies. I focused my research on two genes that code for transcription factors, OCT 4 and GATA 2. OCT 4 is required to maintain stem cells in an undifferentiated state. GATA 2 is thought to be one of the key transcription factors that promote stem cell differentiation into syncytiotrophoblast, a placental cell type. The first step in in situ hybridization is the development of a labeled RNA probe. I designed primers to amplify a 214bp portion of the GATA2 gene sequence by PCR, and then cloned the PCR product into E. coli bacteria. I confirmed the presence and orientation of the insert by using restriction digestion and DNA sequencing. I used bacteria already transformed with a 182bp OCT4 probe sequence to create a riboprobe. I grew up the bacteria overnight, lysed them, and purified the plasmid DNA. I linearized the plasmid with a restriction enzyme, purified it, and transcribed the DNA to RNA, incorporating digoxygenin (DIG) labeled nucleotides. In the near future, I will utilize the same method to transcribe the GATA2 probe, and use both RNA probes to perform in situ hybridizations on hESC.Life Sciences Undergraduate Research Opportunity Progra

Enhancing access to the Bibliome: the TREC 2004 Genomics Track

BACKGROUND: The goal of the TREC Genomics Track is to improve information retrieval in the area of genomics by creating test collections that will allow researchers to improve and better understand failures of their systems. The 2004 track included an ad hoc retrieval task, simulating use of a search engine to obtain documents about biomedical topics. This paper describes the Genomics Track of the Text Retrieval Conference (TREC) 2004, a forum for evaluation of IR research systems, where retrieval in the genomics domain has recently begun to be assessed. RESULTS: A total of 27 research groups submitted 47 different runs. The most effective runs, as measured by the primary evaluation measure of mean average precision (MAP), used a combination of domain-specific and general techniques. The best MAP obtained by any run was 0.4075. Techniques that expanded queries with gene name lists as well as words from related articles had the best efficacy. However, many runs performed more poorly than a simple baseline run, indicating that careful selection of system features is essential. CONCLUSION: Various approaches to ad hoc retrieval provide a diversity of efficacy. The TREC Genomics Track and its test collection resources provide tools that allow improvement in information retrieval systems