428 research outputs found

    Generalized Uncertainty Principle: Implications for Black Hole Complementarity

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    At the heart of the black hole information loss paradox and the firewall controversy lies the conflict between quantum mechanics and general relativity. Much has been said about quantum corrections to general relativity, but much less in the opposite direction. It is therefore crucial to examine possible corrections to quantum mechanics due to gravity. Indeed, the Heisenberg Uncertainty Principle is one profound feature of quantum mechanics, which nevertheless may receive correction when gravitational effects become important. Such generalized uncertainty principle [GUP] has been motivated from not only quite general considerations of quantum mechanics and gravity, but also string theoretic arguments. We examine the role of GUP in the context of black hole complementarity. We find that while complementarity can be violated by large N rescaling if one assumes only the Heisenberg's Uncertainty Principle, the application of GUP may save complementarity, but only if certain N-dependence is also assumed. This raises two important questions beyond the scope of this work, i.e., whether GUP really has the proposed form of N-dependence, and whether black hole complementarity is indeed correct.Comment: Added footnote 5; version accepted by JHE

    Emergency department nurses' experience of implementing discharge planning for emergency department patients in Taiwan : a phenomenographic study

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    During recent reforms to the Taiwanese health care system, discharge planning for hospital patients has become an issue of great concern as a result of shorter hospital stays, increased health care costs and a greater emphasis on community care. There are around five million patients visiting in emergency departments (ED) per year in Taiwan with up to 85% of these, 4,250,000 emergency patients, discharged directly from the emergency department. This significant number of ED visits highlights the need to implement discharge planning in the ED. ED nurses are not only responsible for providing appropriate assessments of a patient's future care needs but also for implementing effective discharge planning as a legal obligation; discharge planning is also a patient's right in Taiwan. For ED nurses to function effectively in the role of discharge planner, it is important that they have a comprehensive understanding of implementing discharge planning. To date, no published research focuses on nurses' experience of implementing discharge planning in the ED in Taiwan. This study is the first step in identifying the experience and understanding of nurses in implementing discharge planning in the ED in Taiwan and may have implications worldwide. The purpose of this study was to identify and describe the experience and understanding of the qualitatively different ways in which ED nursesā€™ experience of implementing discharge planning for emergency patients in Taiwan. In order to identify and describe the experience of implementing discharge planning, the qualitative approach of a phenomenography was chosen. Thirty-two ED nurses in Taiwan who matched the participant selection criteria were asked to describe their experience and understanding of the implementation of discharge planning in the ED. Semi-structured interviews were audio-taped and later transcribed verbatim. The data analysis process focused on identifying and describing ways ED nursesā€™ experience and understanding of implementing discharge planning in the ED. There were two major outcomes of this study: six categories of description and an outcome space. These six categories of description revealed the experience and understanding of implementing discharge planning in the ED. An outcome space portraying the logical relations between the categories of description was identified. The six categories of description were implementing discharge planning as ā€˜getting rid of my patientsā€™; implementing discharge planning as completing routines; implementing discharge planning as being involved in patient education; implementing discharge planning as professional accountability; implementing discharge planning as autonomous practice; implementing discharge planning as demonstrating professional nursing care in ED. The outcome space mapped the three levels of hierarchical relationship between these six categories of description. The referential meaning of implementing discharge planning was the commitment to providing discharge services in the ED. The results of this research contribute to describing the nursesā€™ experience in the implementation of the discharge planning process in the emergency nursing field, in order to provide accurate and effective care to patients discharged from the ED. This study also highlights key insights into the provision of discharge services both in Taiwan and World-wide

    Regular Black Hole Interior Spacetime Supported by Three-Form Field

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    In this paper, we show that a minimally coupled 3-form endowed with a proper potential can support a regular black hole interior. By choosing an appropriate form for the metric function representing the radius of the 2-sphere, we solve for the 3-form field and its potential. Using the obtained solution, we construct an interior black hole spacetime which is everywhere regular. The singularity is replaced with a Nariai-type spacetime, whose topology is dS2ƗS2\text{dS}_2 \times \text{S}^2, in which the radius of the 2-sphere is constant. So long as the interior continues to expand indefinitely, the geometry becomes essentially compactified. The 2-dimensional de Sitter geometry appears despite the negative potential of the 3-form field. Such a dynamical compactification could shed some light on the origin of de Sitter geometry of our Universe, exacerbated by the Swampland conjecture. In addition, we show that the spacetime is geodesically complete. The geometry is singularity-free due to the violation of the null energy condition.Comment: 13 pages, 6 figures. Updated to match the published versio

    Decentralizing Feature Extraction with Quantum Convolutional Neural Network for Automatic Speech Recognition

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    We propose a novel decentralized feature extraction approach in federated learning to address privacy-preservation issues for speech recognition. It is built upon a quantum convolutional neural network (QCNN) composed of a quantum circuit encoder for feature extraction, and a recurrent neural network (RNN) based end-to-end acoustic model (AM). To enhance model parameter protection in a decentralized architecture, an input speech is first up-streamed to a quantum computing server to extract Mel-spectrogram, and the corresponding convolutional features are encoded using a quantum circuit algorithm with random parameters. The encoded features are then down-streamed to the local RNN model for the final recognition. The proposed decentralized framework takes advantage of the quantum learning progress to secure models and to avoid privacy leakage attacks. Testing on the Google Speech Commands Dataset, the proposed QCNN encoder attains a competitive accuracy of 95.12% in a decentralized model, which is better than the previous architectures using centralized RNN models with convolutional features. We also conduct an in-depth study of different quantum circuit encoder architectures to provide insights into designing QCNN-based feature extractors. Neural saliency analyses demonstrate a correlation between the proposed QCNN features, class activation maps, and input spectrograms. We provide an implementation for future studies.Comment: Accepted to IEEE ICASSP 2021. Code is available: https://github.com/huckiyang/QuantumSpeech-QCN

    Hubba: hub objects analyzerā€”a framework of interactome hubs identification for network biology

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    One major task in the post-genome era is to reconstruct proteomic and genomic interacting networks using high-throughput experiment data. To identify essential nodes/hubs in these interactomes is a way to decipher the critical keys inside biochemical pathways or complex networks. These essential nodes/hubs may serve as potential drug-targets for developing novel therapy of human diseases, such as cancer or infectious disease caused by emerging pathogens. Hub Objects Analyzer (Hubba) is a web-based service for exploring important nodes in an interactome network generated from specific small- or large-scale experimental methods based on graph theory. Two characteristic analysis algorithms, Maximum Neighborhood Component (MNC) and Density of Maximum Neighborhood Component (DMNC) are developed for exploring and identifying hubs/essential nodes from interactome networks. Users can submit their own interaction data in PSI format (Proteomics Standards Initiative, version 2.5 and 1.0), tab format and tab with weight values. User will get an email notification of the calculation complete in minutes or hours, depending on the size of submitted dataset. Hubba result includes a rank given by a composite index, a manifest graph of network to show the relationship amid these hubs, and links for retrieving output files. This proposed method (DMNC || MNC) can be applied to discover some unrecognized hubs from previous dataset. For example, most of the Hubba high-ranked hubs (80% in top 10 hub list, and >70% in top 40 hub list) from the yeast protein interactome data (Y2H experiment) are reported as essential proteins. Since the analysis methods of Hubba are based on topology, it can also be used on other kinds of networks to explore the essential nodes, like networks in yeast, rat, mouse and human. The website of Hubba is freely available at http://hub.iis.sinica.edu.tw/Hubba

    Dominance of Tau Burden in Cortical Over Subcortical Regions Mediates Glymphatic Activity and Clinical Severity in PSP

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    Background: Progressive supranuclear palsy (PSP) is a tauopathy that involves subcortical regions but also extends to cortical areas. The clinical impact of different tau protein sites and their influence on glymphatic dysfunction have not been investigated. Patients and Methods: Participants (n = 55; 65.6 Ā± 7.1 years; 29 women) with PSP (n = 32) and age-matched normal controls (NCs; n = 23) underwent 18F-Florzolotau tau PET, MRI, PSP Rating Scale (PSPRS), and Mini-Mental State Examination. Cerebellar gray matter (GM) and parametric estimation of reference signal intensity were used as references for tau burden measured by SUV ratios. Glymphatic activity was measured by diffusion tensor image analysis along the perivascular space (DTI-ALPS). Results: Parametric estimation of reference signal intensity is a better reference than cerebellar GM to distinguish tau burden between PSP and NCs. PSP patients showed higher cortical and subcortical tau SUV ratios than NCs (P < 0.001 and <0.001). Cortical and subcortical tau deposition correlated with PSPRS, UPDRS, and Mini-Mental State Examination scores (all Pā€™s < 0.05). Cortical tau deposition was further associated with the DTI-ALPS index and frontal-temporal-parietal GM atrophy. The DTI-ALPS indexes showed a significantly negative correlation with the PSPRS total scores (P < 0.01). Finally, parietal and occipital lobe tau depositions showed mediating effects between the DTI-ALPS index and PSPRS score. Conclusions: Cortical tau deposition is associated with glymphatic dysfunction and plays a role in mediating glymphatic dysfunction and clinical severity. Our results provide a possible explanation for the worsening of clinical severity in patients with PSP

    Platform Deformation Phase Correction for the AMiBA-13 Coplanar Interferometer

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    [[abstract]]We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.[[notice]]č£œę­£å®Œē•¢[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]電子ē‰ˆ[[booktype]]ē“™ęœ¬[[countrycodes]]US
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