Final Design Report: Polymer Fatigue Characterization Test Method

Polylogix is a team dedicated to the design, build, and testing of a fatigue machine to simulate cyclic loading on a biomedical polymer. This project is sponsored by Endologix, Inc. to provide test data characterizing mechanical material properties of various formulations of polymer used in abdominal aortic aneurysm surgeries. With this project goal, the machine must be able to test the polymer at body conditions; these include a testing temperature of 37°C and a cycling frequency ranging from 1 Hz to 10 Hz. This report proposes the following solution to this design challenge: an AC motor-driven mechanism utilizing a planetary gearbox and pulley system to reduce the speed of the motor to those necessary to achieve testing frequencies of 1 Hz, 2 Hz, 5 Hz, 8 Hz, and 10 Hz. From the drive mechanism, a shaft-mounted cam translates the rotational motion to linear motion through a cam follower. This cam follower carries a load cell and test specimen grip fixtures which clamp onto the specimen to apply cyclic loading. To vary the percent elongation applied to the test specimen, the cam has been designed to be interchangeable to accomplish a range of elongations: 10%, 20%, 30%, 40%, and 50%

Understanding fecal contamination dynamics through the integration of molecular pathogen quantification and land-water interface characteristics

To reduce public health risks and related economic losses, federal guidelines have been established to ensure surface waters meet water quality standards. For example, the United States Environmental Protection Agency released criteria in 1986 that recommended state and local governments establish and enforce regulations to protect ambient waters against naturally-occurring or anthropogenic contaminants. Most of the regulations that were enacted were designed to address recreational water quality because of the risk of illness associated with contact and ingestion of contaminated recreational waters. It wasn’t until 26 years after US EPA’s 1986 release of criteria that new guidance was issued regarding updated tools for managing recreational surface waters. In this report, US EPA included updated recommended criteria for acceptable levels of fecal indicator bacteria, E. coli and enterococci, within surface waters, while also introducing recommended molecular tools. In this dissertation, I applied these molecular methods with current regulatory tools, in an eastern North Carolina (NC) estuary heavily influenced by tidal inundation to better understand potential environmental drivers of surface water contaminant transport. Additionally, enterococci, which is the FIB used for NC’s regulatory assessment of surface water quality, can also be forecast using predictive modeling tools such as multiple linear regression (MLR) models. Similar to what was recommended with regards to incorporating molecular approaches, predictive modeling tools were also a newly suggested monitoring tool recommended by US EPA in the 2012 update. Using a combination of E. coli concentration, tidal phase, and antecedent rainfall, the first part of this dissertation focused on the combined assessment of quantitative-PCR (qPCR), FIB and environmental parameters to show the practicality of using MLR in a regulatory framework to provide estimates of water quality in estuaries, specifically impacted by tidal inundation. Additionally, recent advancements towards the implementation of a fecal indicator virus (FIV), coliphage, have also been proposed as a monitoring tool for use in fresh and marine surface waters. However, the utility of coliphage as an additional water quality management criterion has yet to be fully evaluated. Using US EPA developed protocols for quantification of somatic and male specific coliphage, the second focus of this work looked at the applicability of using such a fecal indicator virus into a monitoring framework by comparing relationships of coliphages with FIB and qMST approaches in surface waters with diffuse source pollution. It was determined that coliphage enumeration in this system proved to be cumbersome, and expensive and, as such, it is suggested that for surface water monitoring, it may be useful to focus on a combination of qPCR and FIB approaches to identify hot spots, and better quantify specific sources of human fecal contamination. Finally, watershed-scale drivers of fecal contamination were assessed in the context of qMST and FIB molecular markers with environmental parameters such as elevation, land use and land cover. Work here was conducted in an urban watershed within the Washington DC metropolitan area and detailed a prioritization of sites across the sampling landscape based on qMST and FIB marker concentrations most associated with risk. This study also incorporated the use of predictive modeling with the ultimate goal of the research being to provide coastal managers approaches that may be incorporated in future water quality monitoring program designs across vast geo-spatial scales.Doctor of Philosoph

‘Stuck in the System’: An Interpretative Phenomenological Analysis of Transmasculine Experiences of Gender Transition in the UK

A gender dysphoria diagnosis is currently required in the UK to access NHS transition-related treatment. However, this approach has been criticised by academics and activists as pathologising, ‘gatekeeping’ transgender identities, and can be viewed by the transgender community as a barrier to necessary medical care. The present research examines transmasculine experiences of gender transition in the UK, focusing on exploring the barriers encountered during identity development and medical transition. Semi-structured interviews were conducted with three individuals, and nine individuals took part in a single focus group. The data were analysed using Interpretative Phenomenological Analysis producing three main themes: ‘Conceptualising Stages of Transition’; ‘NHS Communication and Support’; and ‘Medicalisation, Power and Non-disclosure’. Participants conceptualised access to transition-related treatment as an intrusive and complicated process that negatively impacts identity development. They spoke of barriers such as lack of trans-specific healthcare knowledge, insufficient communication and support from healthcare professionals, and restricted autonomy arising from the pathologisation of trans identities. Results suggest transmasculine individuals may face numerous barriers when trying to access healthcare, and therefore, a move towards the Informed Consent Model could ameliorate many of these barriers and would empower service-users to make informed choices

The three-dimensional structure of the biotin carboxylase-biotin carboxyl carrier protein complex of E. coli acetyl-CoA carboxylase

Acetyl-coenzyme A (acetyl-CoA) carboxylase is a biotin-dependent, multifunctional enzyme that catalyzes the regulated step in fatty acid synthesis. The Escherichia coli enzyme is composed of a homodimeric biotin carboxylase (BC), biotinylated biotin carboxyl carrier protein (BCCP), and an α2β2 heterotetrameric carboxyltransferase. This enzyme complex catalyzes two half-reactions to form malonyl-coenzyme A. BC and BCCP participate in the first half-reaction, whereas carboxyltransferase and BCCP are involved in the second. Three-dimensional structures have been reported for the individual subunits; however, the structural basis for how BCCP reacts with the carboxylase or transferase is unknown. Therefore, we report here the crystal structure of E. coli BCCP complexed with BC to a resolution of 2.49 Å. The protein-protein complex shows a unique quaternary structure and two distinct interfaces for each BCCP monomer. These BCCP binding sites are unique compared to phylogenetically related biotin-dependent carboxylases and therefore provide novel targets for developing antibiotics against bacterial acetyl-CoA carboxylase. © 2013 Elsevier Ltd

Clinician and Patient Experiences of Managing and Living with Oral and Dental Manifestations of Scleroderma: A Scoping Review

Oral and dental manifestations of scleroderma are extremely common, yet they are often overlooked within rheumatology and poorly understood within dentistry. Previous research has indicated the need to understand the oral and dental experiences of people living with scleroderma and those involved in their care. This scoping review aims, for the first time, to comprehensively map what is known regarding the identification and management of oral and dental manifestations of scleroderma, how these are experienced by people living with scleroderma, and to explore key characteristics of barriers and enablers to good oral and dental care in scleroderma. A scoping review was conducted using six databases (Embase, PubMed, PsychINFO, ASSIA, Scopus, and SSCI), according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses – extension for Scoping Review. Grey literature were also included. Studies were eligible for inclusion if the full text and abstract were available in English, published between 2002 and 2022, and focused on the concept of oral and dental care in adults with scleroderma, either relating to identification and management, enablers and barriers to best practice, or patient experiences and wellbeing. Qualitative research which seeks to understand patients’ lived experiences was a notable gap in the literature. Similarly, there was a significant lack of focus on the oral and dental manifestations of scleroderma in rheumatology. Three key features were identified which would facilitate best practice in research and clinical contexts: the necessity of multidisciplinary care; the necessity of centralising patient experience; and the necessity of mitigating barriers to dental care. We conclude that increased awareness of scleroderma within dentistry, and streamlining referral procedures between the disciplines of dentistry and rheumatology, to enable the early identification and management of scleroderma, are crucial

Systems genetics of sensation seeking.

Sensation seeking is a multifaceted, heritable trait which predicts the development of substance use and abuse in humans; similar phenomena have been observed in rodents. Genetic correlations among sensation seeking and substance use indicate shared biological mechanisms, but the genes and networks underlying these relationships remain elusive. Here, we used a systems genetics approach in the BXD recombinant inbred mouse panel to identify shared genetic mechanisms underlying substance use and preference for sensory stimuli, an intermediate phenotype of sensation seeking. Using the operant sensation seeking (OSS) paradigm, we quantified preference for sensory stimuli in 120 male and 127 female mice from 62 BXD strains and the C57BL/6J and DBA/2J founder strains. We used relative preference for the active and inactive levers to dissociate preference for sensory stimuli from locomotion and exploration phenotypes. We identified genomic regions on chromosome 4 (155.236-155.742 Mb) and chromosome 13 (72.969-89.423 Mb) associated with distinct behavioral components of OSS. Using publicly available behavioral data and mRNA expression data from brain regions involved in reward processing, we identified (a) genes within these behavioral QTL exhibiting genome-wide significant cis-eQTL and (b) genetic correlations among OSS phenotypes, ethanol phenotypes and mRNA expression. From these analyses, we nominated positional candidates for behavioral QTL associated with distinct OSS phenotypes including Gnb1 and Mef2c. Genetic covariation of Gnb1 expression, preference for sensory stimuli and multiple ethanol phenotypes suggest that heritable variation in Gnb1 expression in reward circuitry partially underlies the widely reported relationship between sensation seeking and substance use

Results from Navigator GPS Flight Testing for the Magnetospheric MultiScale Mission

No abstract availabl

F17RS SGR No. 2 (Best Wishes Scalise)

A RESOLUTION Conveying Best Wishes to Rep. Steve Scalise on His Recover

Fairness at Trial: The Impact of Procedural Justice and Other Experiential Factors on Criminal Defendants' Perceptions of Court Legitimacy in Poland

A large body of research supports the procedural justice hypothesis that quality of treatment matters more than outcomes for institutional legitimacy. How fairness matters across legal institutions and geographic settings remains an open question, however. This article uses a survey of criminal defendants to test the factors associated with perceived legitimacy of courts in Poland, a country whose judiciary is currently subject to intense political contestation. The findings confirm the primacy of procedural justice, while also illustrating the influence of instrumental performance factors such as time and court organization. This suggests that in contexts of political transition with disputed legal institutions, citizens’ contact with procedurally fair, operationally efficient institutions can support the legitimacy of authorities and strengthen the rule of law