64 research outputs found

    Removing grain boundaries from three-dimensional colloidal crystals using active dopants

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    Using computer simulations we explore how grain boundaries can be removed from three-dimensional colloidal crystals by doping with a small fraction of active colloids. We show that for sufficient self-propulsion, the system is driven into a crystal-fluid coexistence. In this phase separated regime, the active dopants become mobile and spontaneously gather at the grain boundaries. The resulting surface melting and recrystallization of domains result in the motion of the grain boundaries over time and lead to the formation of a large single crystal. However, when the self-propulsion is too low to cause a phase separation, we observe no significant enhancement of grain growth.Comment: 6 pages, 5 figure

    Point Defects in Crystals of Charged Colloids

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    Charged colloidal particles - both on the nano and micron scales - have been instrumental in enhancing our understanding of both atomic and colloidal crystals. These systems can be straightforwardly realized in the lab, and tuned to self-assemble into body-centered cubic (BCC) and face-centered cubic (FCC) crystals. While these crystals will always exhibit a finite number of point defects, including vacancies and interstitials - which can dramatically impact their material properties - their existence is usually ignored in scientific studies. Here, we use computer simulations and free-energy calculations to characterize vacancies and interstitials in both FCC and BCC crystals of point-Yukawa particles. We show that, in the BCC phase, defects are surprisingly more common than in the FCC phase, and the interstitials manifest as so-called crowdions: an exotic one-dimensional defect proposed to exist in atomic BCC crystals. Our results open the door to directly observing these elusive defects in the lab.Comment: 8 pages, 4 figure

    PERANAN WEBSITE DALAM AKTIVITAS PUBLIC RELATIONS SEBAGAI MEDIA PENGHUBUNG ANTARA MASYARAKAT DAN PEMERINTAH DI DISHUBKOMINFO KARANGANYAR

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    SUMMARY Ni Nyoman Ayu A.W, D1613067, Public Relations, Utilization Website Functions in Public Relations Activities as Media Communicator between the Community and the Government in Dishubkominfo Karanganyar, 2016. Kuliah Kerja Media (KKM) or we called Job Training do it by the author in Dishubkominfo Karanganyar. The reason why the author chose Dishubkominfo Karanganyar as a job training (KKM) in the field of communication and information technology, especially because it looks a lot of public relations activities or practice public speaking especially between government Karanganyar Regent and his Deputy with a lot of community. Here Public Relations is a communication method that is where the various forms of communication. Which in Punlic Relations that there is an attempt to realize the harmonious relationship between an organization and its publics. Public Relations is a deliberate effort, planned on an on going basis to create mutual understanding between an institution / organization with the public. Public Relations can also be regarded as an art as well as social science of analyzing trends, predicting their consequences, briefed the leaders of the institution / organization and implementing planned programs to meet the interests of both the institution / organization and the people involved. At the time of the job training writers do a lot of practice public relations or public relations starting from routine activities for official that morning assembly, socializing with office workers, mutual coordination with staff-related staff, and lobbied with related parties participating in activities , documenting coverage and must maintain good relations between the internal and external Dishubkominfo Karanganyar District. Even job training is very useful for writing because it can prepare for the world of work that requires professional workers and authors directly to gain knowledge related to the field of public relations in order practices. Based on reports from the job training the institution Dishubkominfo Karangayar District, the authors conclude that public relations activities are vital to maintaining good relations between the internal and external Dishubkominfo Karanganyar District

    Simultaneous measurement of excitation-contraction coupling parameters identifies mechanisms underlying contractile responses of hiPSC-derived cardiomyocytes

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    Cardiomyocytes from human induced pluripotent stem cells (hiPSC-CMs) are increasingly recognized as valuable for determining the effects of drugs on ion channels but they do not always accurately predict contractile responses of the human heart. This is in part attributable to their immaturity but the sensitivity of measurement tools may also be limiting. Measuring action potential, calcium flux or contraction individually misses critical information that is captured when interrogating the complete excitation-contraction coupling cascade simultaneously. Here, we develop an hypothesis-based statistical algorithm that identifies mechanisms of action. We design and build a high-speed optical system to measure action potential, cytosolic calcium and contraction simultaneously using fluorescent sensors. These measurements are automatically processed, quantified and then assessed by the algorithm. Multiplexing these three critical physical features of hiPSC-CMs allows identification of all major drug classes affecting contractility with detectio

    A randomized controlled trial of eplerenone in asymptomatic phospholamban p.Arg14del carriers

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    INTRODUCTION Phospholamban (PLN; p.Arg14del) cardiomyopathy is an inherited disease caused by the pathogenic p.Arg14del variant in the PLN gene. Clinically, it is characterized by malignant ventricular arrhythmias and progressive heart failure.1,2 Cardiac fibrotic tissue remodelling occurs early on in PLN p.Arg14del carriers.3,4 Eplerenone was deemed a treatment candidate because of its beneficial effects on ventricular remodelling and antifibrotic properties.5,6 We conducted the multicentre randomized trial ‘intervention in PHOspholamban RElated CArdiomyopathy STudy’ (i-PHORECAST) to assess whether treatment with eplerenone of asymptomatic PLN p.Arg14del carriers attenuates disease onset and progression

    A randomized controlled trial of eplerenone in asymptomatic phospholamban p.Arg14del carriers

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    Phospholamban (PLN; p.Arg14del) cardiomyopathy is an inherited disease caused by the pathogenic p.Arg14del variant in the PLN gene. Clinically, it is characterized by malignant ventricular arrhythmias and progressive heart failure.1,2 Cardiac fibrotic tissue remodelling occurs early on in PLN p.Arg14del carriers.3,4 Eplerenone was deemed a treatment candidate because of its beneficial effects on ventricular remodelling and antifibrotic properties.5,6 We conducted the multicentre randomized trial ‘intervention in PHOspholamban RElated CArdiomyopathy STudy’ (i-PHORECAST) to assess whether treatment with eplerenone of asymptomatic PLN p.Arg14del carriers attenuates disease onset and progression

    Blinded, multi-centre evaluation of drug-induced changes in contractility using human induced pluripotent stem cell-derived cardiomyocytes

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    Animal models are 78% accurate in determining whether drugs will alter contractility of the human heart. To evaluate the suitability of human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for predictive safety pharmacology, we quantified changes in contractility, voltage, and/or Ca2+ handling in 2D monolayers or 3D engineered heart tissues (EHTs). Protocols were unified via a drug training set, allowing subsequent blinded multicenter evaluation of drugs with known positive, negative, or neutral inotropic effects. Accuracy ranged from 44% to 85% across the platform-cell configurations, indicating the need to refine test conditions. This was achieved by adopting approaches to reduce signal-to-noise ratio, reduce spontaneous beat rate to ≤ 1 Hz or enable chronic testing, improving accuracy to 85% for monolayers and 93% for EHTs. Contraction amplitude was a good predictor of negative inotropes across all the platform-cell configurations and of positive inotropes in the 3D EHTs. Although contraction- and relaxation-time provided confirmatory readouts forpositive inotropes in 3D EHTs, these parameters typically served as the primary source of predictivity in 2D. The reliance of these “secondary” parameters to inotropy in the 2D systems was not automatically intuitive and may be a quirk of hiPSC-CMs, hence require adaptations in interpreting the data from this model system. Of the platform-cell configurations, responses in EHTs aligned most closely to the free therapeutic plasma concentration. This study adds to the notion that hiPSC-CMs could add value to drug safety evaluation

    Large-scale ICU data sharing for global collaboration: the first 1633 critically ill COVID-19 patients in the Dutch Data Warehouse

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