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A Randomized Controlled Trial of Device Guided, Slow-Paced Respiration in Women with Overactive Bladder Syndrome.
PurposeWe evaluated the effects of device guided, slow-paced respiration on urgency associated urinary symptoms, perceived stress and anxiety, and autonomic function in women with overactive bladder syndrome.Materials and methodsWe performed a randomized, parallel group trial of slow-paced respiration to improve perceived stress and autonomic dysfunction as potential contributors to overactive bladder. Ambulatory women who reported at least 3 voiding or incontinence episodes per day associated with moderate to severe urgency were randomized to use a portable biofeedback device to practice daily, slow, guided breathing exercises or a control device which appeared identical and was reprogrammed to play music without guiding breathing. During 12 weeks we evaluated changes in urinary symptoms by voiding diaries, perceived stress and anxiety by validated questionnaires, and autonomic function by heart rate variability and impedance cardiography.ResultsIn the 161 randomized participants, including 79 randomized to paced respiration and 82 randomized to the control group, the average Ā± SD baseline frequency of voiding or incontinence associated with moderate to severe urgency was 6.9 Ā± 3.4 episodes per day. Compared to controls the participants randomized to paced respiration demonstrated greater improvement in perceived stress (average Perceived Stress Scale score decrease 2.8 vs 1.1, p=0.03) but not in autonomic function markers. During 12 weeks the average frequency of voiding or incontinence associated with moderate to severe urgency, which was the study primary outcome, decreased by a mean of 0.9 Ā± 3.2 episodes per day but no significant between group difference was detected.ConclusionsAmong women with overactive bladder slow-paced respiration was associated with a modest improvement in perceived stress during 12 weeks. However, it was not superior to a music listening control for reducing urinary symptoms or changing autonomic function
A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological Particles with an Acoustic Microdevice.
A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. However, to achieve robust sample manipulation it is necessary to address device integration with the macroscale environment. To realize repeatable, sensitive particle separation with microfluidic devices, this protocol presents a complete automated and integrated microfluidic platform that enables precise processing of 0.15-1.5 ml samples using microfluidic devices. Important aspects of this system include modular device layout and robust fixtures resulting in reliable and flexible world to chip connections, and fully-automated fluid handling which accomplishes closed-loop sample collection, system cleaning and priming steps to ensure repeatable operation. Different microfluidic devices can be used interchangeably with this architecture. Here we incorporate an acoustofluidic device, detail its characterization, performance optimization, and demonstrate its use for size-separation of biological samples. By using real-time feedback during separation experiments, sample collection is optimized to conserve and concentrate sample. Although requiring the integration of multiple pieces of equipment, advantages of this architecture include the ability to process unknown samples with no additional system optimization, ease of device replacement, and precise, robust sample processing
Carbon sequestration monitoring with acoustic double-difference waveform inversion: A case study on SACROC walkaway VSP data
Geological carbon sequestration involves largeāscale injection of carbon dioxide into underground geologic formations and is considered as a potential approach for mitigating global warming. Changes in reservoir properties resulting from the CO2 injection and migration can be characterized using waveform inversions of timeālapse seismic data. The conventional approach for analysis using waveform tomography is to take the difference of the images obtained using baseline and subsequent timeālapse datasets that are inverted independently. By contrast, doubleādifference waveform inversion uses timeālapse seismic datasets to jointly invert for reservoir changes. We apply conventional and double difference methods to a field timeālapse walkaway VSP data set acquired in 2008 and 2009 for monitoring CO2 injection at an enhanced oil recovery field at SACROC, Texas. The doubleādifference waveform inversion gives a cleaner and more easily interpreted image of reservoir changes, as compared to that obtained with the conventional scheme. Our results from the applicatoin of acoustic doubleādifference waveform tomography shows some zones with decreased Pāwave velocity within the reservoir due to CO2 injection and migration
Time-lapse walkaway vertical seismic profile monitoring for CO2 injection at the SACROC enhanced oil recovery field: A case study
Geologic carbon storage involves large-scale injections of carbon dioxide into underground geologic formations. Changes in reservoir properties resulting from CO2CO2 injection and migration can be characterized using monitoring methods with time-lapse seismic data. To achieve economical monitoring, vertical seismic profile (VSP) data are often acquired to survey the local injection area. We investigated the capability of walkaway VSP monitoring for CO2CO2 injection into an enhanced oil recovery field at SACROC, West Texas. VSP data sets were acquired in 2008 and 2009, and CO2CO2 injection took place after the first data acquisition. Because the receivers were located above the injection zone, only reflection data contain the information from the reservoir. Qualitative comparison between reverse-time migration images at different times revealed vertical shifts of the reflectorsā center, indicating the presence of velocity changes. We examined two methods to quantify the changes in velocity: standard full-waveform inversion (FWI) and image-domain wavefield tomography (IDWT). FWI directly inverts seismic waveforms for velocity models. IDWT inverts for the time-lapse velocity changes by matching the baseline and time-lapse migration images. We found that, for the constrained geometry of VSP surveys, the IDWT result was significantly more consistent with a localized change in velocity as expected from a few months of CO2CO2 injection. A synthetic example was used to verify the result from the field data. By contrast, FWI failed to provide quantitative information about the volumetric velocity changes because of the survey geometry and data frequency content
Use of Coniothyrium minitans transformed with the hygromycin B resistance gene to study survival and infection of Sclerotinia sclerotiorum sclerotia in soil
A Coniothyrium minitans strain (T3) co-transformed with the genes for Ī²-glucuronidase (uidA) and hygromycin phosphotransferase (hph), the latter providing resistance to the antibiotic hygromycin B, was used to investigate the survival and infection of sclerotia of Sclerotinia sclerotiorum by C. minitans over time in four different soils. Infection of sclerotia was rapid in all cases, with the behaviour of transformant T3 and wild type parent A69 being similar. Differences were seen between the soils in the rate of infection of sclerotia by C. minitans and in their indigenous fungal populations. Amendment of agar with hygromycin B enabled the quantification of C. minitans in soil by dilution plating where there was a high background of other microorganisms. In Lincoln soil from New Zealand, which had a natural but low population of C. minitans the hygromycin B resistance marker allowed the umambiguous discrimination of the applied transformed isolate from the indigenous hygromycin B sensitive one. In this soil, although the indigenous C. minitans population was detected from sclerotia, none were recovered on the dilution plates, indicating the increased sensitivity of C. minitans detection from soil using sclerotial baiting. C. minitans was a very efficient parasite, being able to infect a large proportion of sclerotia within a relatively short time from an initially low soil population. The addition of hygromycin B to agar also allowed the detection of C. minitans from decaying sclerotia by inhibiting secondary fungal colonisers. This is the first report to show that fungi colonising sclerotia already infected by C. minitans mask the detection of C. minitans from sclerotia rather than displacing the original parasite
What Ambitious Donors Can Learn From The Atlantic Philanthropies' Experience Making Big Bets
By the time The Atlantic Philanthropies closes its doors in 2020, it will have distributed more than 10 million or more. Thirty percent of those bets went to social change causes, including gifts to human services, the environment, and international development. Such big bets have the potential to have big impacts on advancing social change goals. Yet as Bridgespan reported in the December 2015 Stanford Social Innovation Review article,Ā "Making Big Bets for Social Change," investments of this size for social change are rare. Just 20 percent of philanthropic big bets went to social change causes between 2000 and 2012.Why? A number of barriers exist: it's hard to find and structure big bets, "shovel-ready" opportunities are few and far between, personal relationships between donors and nonprofit leaders can take years to nurture, and the long time horizons required for change and often-murky results make it difficult to measure success. In short, big bets on social change can feel risky.The story of Atlantic, however, illustrates what can happen when donors take that risk. This report, What Ambitious Donors Can Learn From The Atlantic Philanthropies' Experience Making Big Bets, looks at a number of big bets Atlantic made and how those achieved significant results. It identified four themes that ran through Atlantic's work and that were particularly evident in its most influential big bets:Pick distinctive investment spots and funding gaps in the landscape.Support organizations and strong leaders, often with unrestricted or capacity-building funding.Pursue advocacy in a complex social, policy and legal environment, and use both traditional grant funding and 501(c)(4) funding as tools.Give with the foundation's end in sight and sustainability in mind.The report also highlights the challenges and failures Atlantic faced along the way. Despite the inherent risk in big bets, Atlantic held the belief that a big bets strategy would be the best way to achieve lasting impact. It is a promising path that is yielding strong results, and Atlantic's experience offers potential strategies for other donors seeking similar goals
Investors Prefer Entrepreneurial Ventures Pitched by Attractive Men
Entrepreneurship is a central path to job creation, economic growth, and prosperity. In the earliest stages of start-up business creation, the matching of entrepreneurial ventures to investors is critically important. The entrepreneurās business proposition and previous experience are regarded as the main criteria for investment decisions. Our research, however, documents other critical criteria that investors use to make these decisions: the gender and physical attractiveness of the entrepreneurs themselves. Across a field setting (three entrepreneurial pitch competitions in the United States) and two experiments, we identify a profound and consistent gender gap in entrepreneur persuasiveness. Investors prefer pitches presented by male entrepreneurs compared with pitches made by female entrepreneurs, even when the content of the pitch is the same. This effect is moderated by male physical attractiveness: attractive males were particularly persuasive, whereas physical attractiveness did not matter among female entrepreneurs
HIV infection is an independent risk factor for decreased 6-minute walk test distance.
BackgroundAmbulatory function predicts morbidity and mortality and may be influenced by cardiopulmonary dysfunction. Persons living with HIV (PLWH) suffer from a high prevalence of cardiac and pulmonary comorbidities that may contribute to higher risk of ambulatory dysfunction as measured by 6-minute walk test distance (6-MWD). We investigated the effect of HIV on 6-MWD.MethodsPLWH and HIV-uninfected individuals were enrolled from 2 clinical centers and completed a 6-MWD, spirometry, diffusing capacity for carbon monoxide (DLCO) and St. George's Respiratory Questionnaire (SGRQ). Results of 6-MWD were compared between PLWH and uninfected individuals after adjusting for confounders. Multivariable linear regression analysis was used to determine predictors of 6-MWD.ResultsMean 6-MWD in PLWH was 431 meters versus 462 in 130 HIV-uninfected individuals (p = 0.0001). Older age, lower forced expiratory volume (FEV1)% or lower forced vital capacity (FVC)%, and smoking were significant predictors of decreased 6-MWD in PLWH, but not HIV-uninfected individuals. Lower DLCO% and higher SGRQ were associated with lower 6-MWD in both groups. In a combined model, HIV status remained an independent predictor of decreased 6-MWD (Mean difference = -19.9 meters, p = 0.005).ConclusionsHIV infection was associated with decreased ambulatory function. Airflow limitation and impaired diffusion capacity can partially explain this effect. Subjective assessments of respiratory symptoms may identify individuals at risk for impaired physical function who may benefit from early intervention
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