24 research outputs found
Minimal grid diagrams of the prime knots with crossing number 13 and arc index 13
We give a list of minimal grid diagrams of the 13 crossing prime
nonalternating knots which have arc index 13. There are 9,988 prime knots with
crossing number 13. Among them 4,878 are alternating and have arc index 15.
Among the other nonalternating knots, 49, 399, 1,412 and 3,250 have arc index
10, 11, 12, and 13, respectively. We used the Dowker-Thistlethwaite code of the
3,250 knots provided by the program Knotscape to generate spanning trees of the
corresponding knot diagrams to obtain minimal arc presentations in the form of
grid diagrams.Comment: 57 pages, 5 figures, 1 table and 3250 grid diagram
Retrospective analysis of autoimmune hepatitis-primary biliary cirrhosis overlap syndrome in Korea: characteristics, treatments, and outcomes
Background/AimsOverlap syndrome of autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) (AIH-PBC overlap syndrome) is a rare disease that has not been clearly characterized in Korean patients. This study investigated the clinical features of AIH-PBC overlap syndrome compared with those of AIH and PBC alone.MethodsThis retrospective cohort study included 158 consecutive patients who were diagnosed as AIH (n=61), PBC (n=81), or AIH-PBC overlap syndrome (n=9) based on the Paris and the International Autoimmune Hepatitis Group (IAIHG) criteria from 2001 to 2011 in Korea. We compared the clinical features of these three groups retrospectively, including their biochemical characteristics, treatments, responses, and clinical outcomes.ResultsThe AIH-PBC overlap syndrome patients exhibited biochemical characteristics of both AIH and PBC, and showed a similar response to ursodeoxycholic acid (UDCA) monotherapy as for the PBC patients. However, the response of AIH-PBC overlap syndrome patients to UDCA and steroid combination therapy was worse than the response of AIH patients to steroid-based therapy (P=0.024). Liver cirrhosis developed more rapidly in AIH-PBC overlap syndrome patients than in AIH patients group (P=0.013), but there was no difference between AIH-PBC overlap syndrome patients and PBC patients. The rates of developing hepatic decompensation did not differ significantly between the groups.ConclusionsThe AIH-PBC overlap syndrome patients exhibited a worse response to UDCA and steroid combination therapy and a faster cirrhotic progression compared with AIH patients
Dual-Color-Emitting Carbon Nanodots for Multicolor Bioimaging and Optogenetic Control of Ion Channels
The development of intrinsically multicolor-emitting carbon nanodots (CNDs) has been one of the great challenges for their various fields of applications. Here, the controlled electronic structure engineering of CNDs is performed to emit two distinct colors via the facile surface modification with 4-octyloxyaniline. The so-called dual-color-emitting CNDs (DC-CNDs) can be stably encapsulated within poly(styrene-co-maleic anhydride) (PSMA). The prepared water-soluble DC-CNDs@PSMA can be successfully applied to in vitro and in vivo dual-color bioimaging and optogenetics. In vivo optical imaging can visualize the biodistribution of intravenously injected DC-CNDs@PSMA. In addition, the light-triggered activation of ion channel, channelrhodopsin-2, for optogenetic applications is demonstrated. As a new type of fluorophore, DC-CNDs offer a big insight into the design of charge-transfer complexes for various optical and biomedical applications.112Ysciescopu
Nanoengineering room temperature ferroelectricity into orthorhombic SmMnO 3 films
Abstract: Orthorhombic RMnO3 (R = rare-earth cation) compounds are type-II multiferroics induced by inversion-symmetry-breaking of spin order. They hold promise for magneto-electric devices. However, no spontaneous room-temperature ferroic property has been observed to date in orthorhombic RMnO3. Here, using 3D straining in nanocomposite films of (SmMnO3)0.5((Bi,Sm)2O3)0.5, we demonstrate room temperature ferroelectricity and ferromagnetism with TC,FM ~ 90 K, matching exactly with theoretical predictions for the induced strain levels. Large in-plane compressive and out-of-plane tensile strains (−3.6% and +4.9%, respectively) were induced by the stiff (Bi,Sm)2O3 nanopillars embedded. The room temperature electric polarization is comparable to other spin-driven ferroelectric RMnO3 films. Also, while bulk SmMnO3 is antiferromagnetic, ferromagnetism was induced in the composite films. The Mn-O bond angles and lengths determined from density functional theory explain the origin of the ferroelectricity, i.e. modification of the exchange coupling. Our structural tuning method gives a route to designing multiferroics
Locomotion Control for Many-Muscle Humanoids
We present a biped locomotion controller for humanoid models actuated by more than a hundred Hill-type muscles. The key component of the controller is our novel algorithm that can cope with step-based biped locomotion balancing and the coordination of many nonlinear Hill-type muscles simultaneously. Minimum effort muscle activations are calculated based on muscle contraction dynamics and online quadratic programming. Our controller can faithfully reproduce a variety of realistic biped gaits (e.g., normal walk, quick steps, and fast run) and adapt the gaits to varying conditions (e.g., muscle weakness, tightness, joint dislocation, and external pushes) and goals (e.g., pain reduction and efficiency maximization). We demonstrate the robustness and versatility of our controller with examples that can only be achieved using highly-detailed musculoskeletal models with many muscles.N
Photoluminescent and biodegradable porous silicon nanoparticles for biomedical imaging
Porous silicon nanoparticles (PSiNPs) have attracted increasing interest as biomedical probes for drug delivery and imaging. In particular, a set of unique properties including biodegradability, intrinsic photoluminescence, and favorable mesoporous structure providing high drug loading allow PSiNPs to address current challenges of translational nanomedicine. In this review, the important features of PSiNPs considered as a biomedical imaging probe will be concisely discussed along with recent advances in fabrication and theranostic applications. Firstly, an overview of PSiNP fabrication with controllable geometry through top-down or bottom-up strategies is provided. Next, intrinsic photoluminescence, the key element allowing application of PSiNPs as an imaging agent, is highlighted with near-infrared emission and micro-second scale lifetime. Emerging technologies for biodegradable nanomedicine based on PSiNPs are then presented. Advances of PSiNPs for disease treaments including photodynamic and photothermal therapeutics are also discussed to open up potential translational medical strategies. In addition, the versatile surface chemistry and modification of PSiNPs in the context of biomedical applications are extensively discussed. Overall, the promising characteristics of PSiNPs encourage further exploration for biomedical research and translational medical platforms, particularly in biomedical imaging
Understanding the stability of deep control policies for biped locomotion
© 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Achieving stability and robustness is the primary goal of biped locomotion control. Recently, deep reinforcement learning (DRL) has attracted great attention as a general methodology for constructing biped control policies and demonstrated significant improvements over the previous state-of-the-art control methods. Although deep control policies are more advantageous compared with previous controller design approaches, many questions remain: Are deep control policies as robust as human walking? Does simulated walking involve strategies similar to human walking for maintaining balance? Does a particular gait pattern affect human and simulated walking similarly? What do deep policies learn to achieve improved gait stability? The goal of this study is to address these questions by evaluating the push-recovery stability of deep policies compared with those of human subjects and a previous feedback controller. Furthermore, we conducted experiments to evaluate the effectiveness of variants of DRL algorithms.N
VitalDB, a high-fidelity multi-parameter vital signs database in surgical patients
In modern anesthesia, multiple medical devices are used simultaneously to comprehensively monitor real-time vital signs to optimize patient care and improve surgical outcomes. However, interpreting the dynamic changes of time-series biosignals and their correlations is a difficult task even for experienced anesthesiologists. Recent advanced machine learning technologies have shown promising results in biosignal analysis, however, research and development in this area is relatively slow due to the lack of biosignal datasets for machine learning. The VitalDB (Vital Signs DataBase) is an open dataset created specifically to facilitate machine learning studies related to monitoring vital signs in surgical patients. This dataset contains high-resolution multi-parameter data from 6,388 cases, including 486,451 waveform and numeric data tracks of 196 intraoperative monitoring parameters, 73 perioperative clinical parameters, and 34 time-series laboratory result parameters. All data is stored in the public cloud after anonymization. The dataset can be freely accessed and analysed using application programming interfaces and Python library. The VitalDB public dataset is expected to be a valuable resource for biosignal research and development.N
Energy-filtered acceleration of charge-carrier transport in organic thermoelectric nanocomposites
Nanocomposite systems have notably improved the thermoelectric (TE) figure-of-merit ZT of organic materials; however, further studies are required to reveal the underlying TE charge transport in the heterogeneous organic system. Here, the relationship between the TE properties and the energy structure of the organic TE nanocomposite is investigated by developing different internal potential steps in poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) with carbon quantum dots (CQDs) of tunable electronic bands. The charge transport across the insulating PSS layer was facilitated by embedded CQDs, which accelerated the high-energy hole transport and increased both the Seebeck coefficient and the electrical conductivity. With a carefully tuned internal potential step, PEDOT:PSS/CQD nanocomposite showed a power factor of 584 μW m-1 K-2, which was 3 times larger than that of pristine PEDOT:PSS and yields a high ZT = 0.32. This work provides a fresh perspective on the energy-filtering effect for the design of high-performance organic TE nanocomposites.11Nsciescopu