426 research outputs found
Rolling Stability of a Power-Generating Tumbleweed Rover
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140405/1/1.a32883.pd
Entangled Bessel beams
Orbital angular momentum (OAM) entanglement is investigated in the
Bessel-Gauss (BG) basis. Having a readily adjustable radial scale, BG modes
provide a more favourable basis for OAM entanglement over Laguerre-Gaussian
(LG) modes. The OAM bandwidth in terms of BG modes can be increased by
selection of particular radial modes and leads to a flattening of the spectrum.
The flattening of the spectrum allows for higher entanglement. We demonstrate
increased entanglement in terms of BG modes by performing a Bell-type
experiment and violating the appropriate Clauser Horne Shimony Holt (CHSH)
inequality. In addition, we reconstruct the quantum state of BG modes entangled
in high-dimensions.Comment: 8 pages, 4 figure
Suppression of Epithelial to Mesenchymal Transitioning (EMT) Enhances Ex Vivo Reprogramming of Human Exocrine Pancreatic Tissue towards Functional Insulin Producing ÎČ-Like Cells
Because of the lack of tissue available for islet transplantation, new sources of ÎČ-cells have been sought for the treatment of type 1 diabetes. The aim of this study was to determine whether the human exocrine-enriched fraction from the islet isolation procedure could be reprogrammed to provide additional islet tissue for transplantation. The exocrine-enriched cells rapidly dedifferentiated in culture and grew as a mesenchymal monolayer. Genetic lineage tracing confirmed that these mesenchymal cells arose, in part, through a process of epithelial-to-mesenchymal transitioning (EMT). A protocol was developed whereby transduction of these mesenchymal cells with adenoviruses containing Pdx1, Ngn3, MafA, and Pax4 generated a population of cells that were enriched in glucagon-secreting α-like cells. Transdifferentiation or reprogramming toward insulin-secreting ÎČ-cells was enhanced, however, when using unpassaged cells in combination with inhibition of EMT by inclusion of Rho-associated kinase (ROCK) and transforming growth factor-ÎČ1 inhibitors. Resultant cells were able to secrete insulin in response to glucose and on transplantation were able to normalize blood glucose levels in streptozotocin diabetic NOD/SCID mice. In conclusion, reprogramming of human exocrine-enriched tissue can be best achieved using fresh material under conditions whereby EMT is inhibited, rather than allowing the culture to expand as a mesenchymal monolayer
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Movements and Settlement Site Selection of Pygmy Rabbits After Experimental Translocation
We investigated the movements and selection of settlement sites of translocated pygmy rabbits (Brachylagus idahoensis) in southeastern Oregon from June to December 2008. We captured, radio tagged, and translocated 59 pygmy rabbits across big sagebrush (Artemisia tridentata ssp.) habitat with 3 categories of landscape fragmentation. We used radio telemetry to track the movements and document the fates of translocated individuals. We used Geographic Information Systems (GIS) and spatial analysis software (FRAGSTATS) to analyze the post-release movements and selection of settlement sites by pygmy rabbits. We found that pygmy rabbits settled closer to their release sites as the amount big sagebrush cover on the surrounding landscape increased. In addition, translocated pygmy rabbits settled on sites that, on average, had greater cover, greater landscape connectivity, and fewer but larger patches of big sagebrush than were present at their capture sites. Current or past presence of conspecifics also appeared to be a factor in selection of settlement sites by pygmy rabbits. Successful translocation of wild pygmy rabbits for augmenting depleted populations will require selection of release locations with continuous big sagebrush cover and a history of pygmy rabbit presence. Managers should also expect to lose a portion of translocated pygmy rabbits to homing attempts, post-release dispersal, and predation, so large numbers of individuals should be released to establish resident populations. 2013 The Wildlife Society.Keywords: habitat fragmentation, pygmy rabbit, sagebrush, Brachylagus idahoensis, dispersal, Great Basin, radio telemetry, experimental translocatio
Physician decision making in selection of second-line treatments in immune thrombocytopenia in children.
Immune thrombocytopenia (ITP) is an acquired autoimmune bleeding disorder which presents with isolated thrombocytopenia and risk of hemorrhage. While most children with ITP promptly recover with or without drug therapy, ITP is persistent or chronic in others. When needed, how to select second-line therapies is not clear. ICON1, conducted within the Pediatric ITP Consortium of North America (ICON), is a prospective, observational, longitudinal cohort study of 120 children from 21 centers starting second-line treatments for ITP which examined treatment decisions. Treating physicians reported reasons for selecting therapies, ranking the top three. In a propensity weighted model, the most important factors were patient/parental preference (53%) and treatment-related factors: side effect profile (58%), long-term toxicity (54%), ease of administration (46%), possibility of remission (45%), and perceived efficacy (30%). Physician, health system, and clinical factors rarely influenced decision-making. Patient/parent preferences were selected as reasons more often in chronic ITP (85.7%) than in newly diagnosed (0%) or persistent ITP (14.3%, Pâ=â.003). Splenectomy and rituximab were chosen for the possibility of inducing long-term remission (Pâ<â.001). Oral agents, such as eltrombopag and immunosuppressants, were chosen for ease of administration and expected adherence (Pâ<â.001). Physicians chose rituximab in patients with lower expected adherence (Pâ=â.017). Treatment choice showed some physician and treatment center bias. This study illustrates the complexity and many factors involved in decision-making in selecting second-line ITP treatments, given the absence of comparative trials. It highlights shared decision-making and the need for well-conducted, comparative effectiveness studies to allow for informed discussion between patients and clinicians
The International Bathymetric Chart of the Arctic Ocean (IBCAO) Version 3.0
[1] The International Bathymetric Chart of the Arctic Ocean (IBCAO) released its first gridded bathymetric compilation in 1999. The IBCAO bathymetric portrayals have since supported a wide range of Arctic science activities, for example, by providing constraint for ocean circulation models and the means to define and formulate hypotheses about the geologic origin of Arctic undersea features. IBCAO Version 3.0 represents the largest improvement since 1999 taking advantage of new data sets collected by the circum-Arctic nations, opportunistic data collected from fishing vessels, data acquired from US Navy submarines and from research ships of various nations. Built using an improved gridding algorithm, this new grid is on a 500 meter spacing, revealing much greater details of the Arctic seafloor than IBCAO Version 1.0 (2.5 km) and Version 2.0 (2.0 km). The area covered by multibeam surveys has increased from âŒ6% in Version 2.0 to âŒ11% in Version 3.0
Characterization of pre-transplant psychosocial burden in an integrated national islet transplant programme
The psychological burden experienced by people with diabetes prior to islet transplantation is recognized but has not been studied comprehensively, especially in relation to glycemia. Therefore, we conducted a rigorous pre-operative psychosocial profile of UK islet transplant recipients, and compared groups with higher/lower HbA1 c to test the null hypothesis that pre-transplant hypoglycemia awareness and psychosocial burden would not be related to baseline HbA1 c in this high-risk cohort. Pre-transplant, recipients (n = 44) completed validated hypoglycemia awareness questionnaires and generic/diabetes-specific measures of psychological traits and states. Scores were compared in groups, dichotomized by HbA1 c (â€8% versus >8%). Participants were aged (mean±SD) 53 ± 10 years; 64% were women; with HbA1 c 8.3 ± 1.7%. Median rate of severe hypoglycemia over the preceding 12 months was 13 events/person-year and 90% had impaired awareness of hypoglycemia (Gold/Clarke score â„4). Participants had elevated fear of hypoglycemia (HFS-II Worry), impaired diabetes-specific quality of life (DQoL) and low generic health status (SF-36; EQ-5D). One quarter reported scores indicating likely anxiety/depression (HAD). Dispositional optimism (LOT-R) and generalized self-efficacy (GSE) were within published ânorms.â Despite negative perceptions of diabetes (including low personal control), participants were confident that islet transplantation would help (BIPQ). Hypoglycemia awareness and psychosocial profile were comparable in lower (n = 24) and higher (n = 20) HbA1 c groups. Islet transplant candidates report sub-optimal generic psychological states (anxiety/depressive symptoms), health status and diabetes-specific psychological states (fear of hypoglycemia, diabetes-specific quality of life). While their generic psychological traits (optimism, self-efficacy) are comparable with the general population, they are highly optimistic about forthcoming transplant. HbA1 c is not a proxy measure of psychosocial burden, which requires the use of validated questionnaires to systematically identify those who may benefit most from psychological assessment and support
Bostonia: The Boston University Alumni Magazine. Volume 31
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
The impact of islet mass, number of transplants, and time between transplants on graft function in a national islet transplant program
The UK islet allotransplant program is nationally funded to deliver one or two transplants over 12 months to individuals with type 1 diabetes and recurrent severe hypoglycemia. Analyses were undertaken 10 years after program inception to evaluate associations between transplanted mass; single versus two transplants; time between two transplants and graft survival (stimulated C-peptide >50 pmol/L) and function. In total, 84 islet transplant recipients were studied. Uninterrupted graft survival over 12 months was attained in 23 (68%) single and 47 (94%) (p =.002) two transplant recipients (separated by [median (IQR)] 6 (3â8) months). 64% recipients of one or two transplants with uninterrupted function at 12 months sustained graft function at 6 years. Total transplanted mass was associated with Mixed Meal Tolerance Test stimulated C-peptide at 12 months (p <.01). Despite 1.9-fold greater transplanted mass in recipients of two versus one islet infusion (12 218 [9291â15 417] vs. 6442 [5156â7639] IEQ/kg; p <.0001), stimulated C-peptide was not significantly higher. Shorter time between transplants was associated with greater insulin dose reduction at 12 months (beta â0.35; p =.02). Graft survival over the first 12 months was greater in recipients of two versus one islet transplant in the UK program, although function at 1 and 6 years was comparable. Minimizing the interval between 2 islet infusions may maximize cumulative impact on graft function
Surgical Treatment for Recurrent Bulbar Urethral Stricture: A Randomised Open-label Superiority Trial of Open Urethroplasty Versus Endoscopic Urethrotomy (the OPEN Trial)
BackgroundUrethral stricture affects 0.9% of men. Initial treatment is urethrotomy. Approximately, half of the strictures recur within 4âŻyr. Options for further treatment are repeat urethrotomy or open urethroplasty.ObjectiveTo compare the effectiveness and cost-effectiveness of urethrotomy with open urethroplasty in adult men with recurrent bulbar urethral stricture.Design, setting, and participantsThis was an open label, two-arm, patient-randomised controlled trial. UK National Health Service hospitals were recruited and 222 men were randomised to receive urethroplasty or urethrotomy.InterventionUrethrotomy is a minimally invasive technique whereby the narrowed area is progressively widened by cutting the scar tissue with a steel blade mounted on a urethroscope. Urethroplasty is a more invasive surgery to reconstruct the narrowed area.Outcome measurements and statistical analysisThe primary outcome was the profile over 24 mo of a patient-reported outcome measure, the voiding symptom score. The main clinical outcome was time until reintervention.Results and limitationsThe primary analysis included 69 (63%) and 90 (81%) of those allocated to urethroplasty and urethrotomy, respectively. The mean difference between the urethroplasty and urethrotomy groups was â0.36 (95% confidence interval [CI] â1.74 to 1.02). Fifteen men allocated to urethroplasty needed a reintervention compared with 29 allocated to urethrotomy (hazard ratio [95% CI] 0.52 [0.31â0.89]).ConclusionsIn men with recurrent bulbar urethral stricture, both urethroplasty and urethrotomy improved voiding symptoms. The benefit lasted longer for urethroplasty.Patient summaryThere was uncertainty about the best treatment for men with recurrent bulbar urethral stricture. We randomised men to receive one of the following two treatment options: urethrotomy and urethroplasty. At the end of the study, both treatments resulted in similar and better symptom scores. However, the urethroplasty group had fewer reinterventions
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