56 research outputs found
Variational methods for fitting complex Bayesian mixed effects models to health data
No full text© 2016 John Wiley & Sons, Ltd. We consider approximate inference methods for Bayesian inference to longitudinal and multilevel data within the context of health science studies. The complexity of these grouped data often necessitates the use of sophisticated statistical models. However, the large size of these data can pose significant challenges for model fitting in terms of computational speed and memory storage. Our methodology is motivated by a study that examines trends in cesarean section rates in the largest state of Australia, New South Wales, between 1994 and 2010. We propose a group-specific curve model that encapsulates the complex nonlinear features of the overall and hospital-specific trends in cesarean section rates while taking into account hospital variability over time. We use penalized spline-based smooth functions that represent trends and implement a fully mean field variational Bayes approach to model fitting. Our mean field variational Bayes algorithms allow a fast (up to the order of thousands) and streamlined analytical approximate inference for complex mixed effects models, with minor degradation in accuracy compared with the standard Markov chain Monte Carlo methods
Event-related potential responses of individuals with Autism spectrum development to atypical auditory processing-a narrative review
No full text202505 bcwcVersion of RecordOthersInnovation and Technology Fund (ITF) of Hong Kong matching with Innovation Technology Company Limited; Peter T. C. Lee Endowed Professorship fundPublishedSpringer Nature (2025)T
Yi wei fei xian xing Kelaiyin--Kedeng xi tong re li xue te xing zhi yan jiu
No full textLee Joy Yan Agatha.Thesis (M.Phil.)--Chinese University of Hong Kong, 1999.Includes bibliographical references (leaves [112]-114).Text in English; abstracts in English and Chinese.Lee Joy Yan Agatha.Abstract --- p.iiAcknowledgement --- p.iiiContents --- p.ivList of Figures --- p.viiiList of Tables --- p.xiiChapter Chapter 1. --- Introduction --- p.1Chapter Chapter 2. --- The Transfer Integral Equation Method --- p.3Chapter 2.1 --- The System --- p.3Chapter 2.1.1 --- The Hamiltonian --- p.4Chapter 2.1.2 --- The length parameter --- p.5Chapter 2.1.3 --- The temperature parameter --- p.5Chapter 2.2 --- The Transfer Integral Equation --- p.6Chapter 2.2.1 --- The partition function --- p.6Chapter 2.2.2 --- The transfer integral equation --- p.6Chapter 2.2.3 --- The pseudo-Schrodinger equation approximation --- p.7Chapter 2.2.4 --- Distribution function of the displacements --- p.9Chapter 2.3 --- The Thermodynamics --- p.10Chapter 2.3.1 --- Internal energy and heat capacity --- p.10Chapter 2.3.2 --- Displacement fluctuation --- p.12Chapter 2.3.3 --- Displacement correlation function --- p.12Chapter Chapter 3. --- The Φ4 Chain --- p.14Chapter 3.1 --- Soliton In The Chain --- p.15Chapter 3.1.1 --- Kink soliton and antikink soliton --- p.15Chapter 3.1.2 --- Energy of a static kink --- p.18Chapter 3.2 --- Low Temperature WKB Approximation for the Φ4 Chain --- p.20Chapter 3.2.1 --- The ground state energy ε0 and tunneling-splitting contribution --- p.20Chapter 3.2.2 --- First order WKB approximation of ΨRo( φ) --- p.22Chapter 3.2.3 --- Second order WKB wavefunction ΨRo( φ)） --- p.26Chapter 3.2.4 --- Third order WKB wavefunction for ΨRo( φ) --- p.27Chapter 3.3 --- Thermodynamics --- p.28Chapter 3.3.1 --- Ground state energy ε0 and wavefunction Ψo( φ) --- p.28Chapter 3.3.2 --- Internal energy and heat capacity --- p.33Chapter 3.3.3 --- Displacement correlation function --- p.36Chapter Chapter 4. --- Other Nonlinear Klein-Gordon Models --- p.42Chapter 4.1 --- The φ8 Chain --- p.42Chapter 4.1.1 --- The potential --- p.42Chapter 4.1.2 --- The ground state energy εo and wavefunction Ψo( φ) --- p.44Chapter 4.1.3 --- Internal energy and heat capacity --- p.49Chapter 4.1.4 --- Displacement correlation function cyy(n) --- p.51Chapter 4.2 --- The Gaussian-Double-Well Chains --- p.53Chapter 4.2.1 --- The potential --- p.53Chapter 4.2.2 --- The ground state energy εo and wavefunction ψo --- p.55Chapter 4.2.3 --- Internal energy and heat capacity --- p.58Chapter 4.2.4 --- Displacement correlation function cyy(n) --- p.59Chapter 4.3 --- Comparison Between Different NKG Models --- p.61Chapter 4.3.1 --- The potentials --- p.61Chapter 4.3.2 --- Ground state energy εo and wavefunction ψo(ψ) --- p.65Chapter 4.3.3 --- Internal energy and heat capacity --- p.68Chapter 4.3.4 --- Displacement fluctuation --- p.70Chapter 4.3.5 --- Displacement correlation function cyy(n) --- p.71Chapter 4.4 --- Linear Response of a NKG Chain to a Static Perturbing Field --- p.75Chapter 4.4.1 --- The external perturbing field --- p.75Chapter 4.4.2 --- The linear response --- p.75Chapter 4.4.3 --- Linear response of an array of weakly coupled NKG chains --- p.80Chapter Chapter 5. --- Quantum Corrections --- p.86Chapter 5.1 --- The Effective Potential --- p.86Chapter 5.1.1 --- The smearing parameter --- p.86Chapter 5.1.2 --- The effective potential --- p.88Chapter 5.2 --- Quantum Corrections on Thermodynamics --- p.90Chapter 5.2.1 --- The ground state energy εo and wavefunction ψo(ψ) --- p.90Chapter 5.2.2 --- The heat capacity --- p.94Chapter 5.2.3 --- Displacement correlation function and displacement fluctuation --- p.97Chapter Chapter 6. --- Conclusion --- p.103Appendix A. Infinite-Square-Well Basis Diagonalization --- p.105Appendix B. Oscillator Basis Diagonalization --- p.110Bibliography --- p.11
The use of traditional Chinese medicine and food avoidance by Chinese breast cancer patients
No full textAim: To determine the prevalence and pattern of the use of traditional Chinese medicine (TCM) and food avoidance in Chinese breast cancer patients.
Methods: 824 consecutive Chinese breast cancer patients who received operation at our Centre were recruited to fill a questionnaire on TCM and food avoidance.
Results: Data of 802 participants was analysed, excluding 22 questionnaires with missing data (completion rate 97.3%). 181 (22.0%) patients were on TCM after the diagnosis of breast cancer. Patients on TCM were younger (P = 0.000) and had higher educational level (P = 0.038) as compared to those not on TCM. There was no association between marital status, occupation, household income, number of dependents and TCM use.
The most frequently cited reason for TCM use was body conditioning (82.5%). Nearly half the patients (47.7%) did not inform their doctors of TCM use.
495 (61.7%) patients reported food avoidance after breast cancer diagnosis, with chicken being the most commonly avoided (63%).
Conclusion: While younger patients with higher education tended to opt for TCM use, there did not appear to be any significant association with other demographic factors. Breast cancer patients were commonly advised to avoid consumption of fried and fatty foods but this study showed that the majority were under a false belief that avoidance of chicken was most important. Given the increasing use of TCM as an adjunct to therapy in breast cancer patients, this study highlighted the need for further research in this area and for better education on healthy balanced diet.abstrac
Epigenetic regulation of centromere function
No full textThe centromere is a specialized region on the chromosome that directs equal chromosome segregation. Centromeres are usually not defined by DNA sequences alone. How centromere formation and function are determined by epigenetics is still not fully understood. Active centromeres are often marked by the presence of centromeric-specific histone H3 variant, centromere protein A (CENP-A). How CENP-A is assembled into the centromeric chromatin during the cell cycle and propagated to the next cell cycle or the next generation to maintain the centromere function has been intensively investigated. In this review, we summarize current understanding of how post-translational modifications of CENP-A and other centromere proteins, centromeric and pericentric histone modifications, non-coding transcription and transcripts contribute to centromere function, and discuss their intricate relationships and potential feedback mechanisms.link_to_subscribed_fulltex
Magnetization Reversal of Exchange-biased Bilayers and Trilayers Probed using Front and Back LT-MOKE
No full textMagneto-optical Kerr effect (MOKE) magnetometry was used to investigate magnetization reversal dynamics in 30-nm NiFe/15-nm FeMn, 15-nm FeMn/30-nm CoFe bilayers, and 30-nm NiFe/(2,10)-nm FeMn/30-nm CoFe trilayers. The in-plane magnetization components of each ferromagnetic layer, both parallel and perpendicular to the applied field, were separately determined by measuring the longitudinal and transverse MOKE hysteresis loops from both the front and back sides of the film for an oblique incident s-polarized beam. The magnetization of the FeMn/CoFe bilayer was reversed abruptly and symmetrically through nucleation and domain wall propagation, while that of the NiFe/FeMn bilayer was reversed asymmetrically with a dominant rotation. In the NiFe/FeMn/CoFe trilayers, the magnetic reversal of the two ferromagnetic layers proceeded via nucleation and domain wall propagation for 2-nm FeMn, but via asymmetric rotation for 10-nm FeMn. The exchange-biased ferromagnetic layers showed the magnetization reversal along the same path in the film plane for the decreasing and increasing field branches from transverse MOKE hysteresis loops, which can be qualitatively explained by the theoretical model of the exchange-biased ferromagnetic/antiferromagnetic systems.This work was supported by KOSEF (Nuclear R&D
program) and KICOS (Global Partnership Program, No.
K20702020014) through a grant provided by the Korean
government (MEST). CYY was supported by Nano R&D
program through the Korea Science and Engineering
Foundation funded by the Ministry of Science & Technology
(2008-02553)
Simplified analytic formulae for magneto-optical Kerr effects in ultrathin magnetic films
No full textExpressions are presented for various magneto-optical Kerr effects in the ultrathin film limit with arbitrary magnetization direction by considering the multiple reflections within an optically thin film. The Kerr effect of p- and s-polarization consists of products of two factors: the prefactor, dependent only on the optical parameters of the system, and the main factor of the polar Kerr effect for normal incidence in the ultrathin limit. (C) 1999 Elsevier Science B.V. All rights reserved.This work was supported by the Creative Research Initiatives of the Ministry of Science and Technology of Korea, and
one author (CYY) wishes to acknowledge the financial support of the Korea Research Foundation made in program
Year 1997, and the hospitality of Argonne National Laboratory. Argonne was supported by the US Department of
Energy, BES-Material Science, under contract No. W-31-109-ENG-38
Hamiltonian simulation with optimal sample complexity
No full text© 2017 Author(s). We investigate the sample complexity of Hamiltonian simulation: how many copies of an unknown quantum state are required to simulate a Hamiltonian encoded by the density matrix of that state? We show that the procedure proposed by Lloyd, Mohseni, and Rebentrost [Nat. Phys., 10(9):631-633, 2014] is optimal for this task. We further extend their method to the case of multiple input states, showing how to simulate any Hermitian polynomial of the states provided. As applications, we derive optimal algorithms for commutator simulation and orthogonality testing, and we give a protocol for creating a coherent superposition of pure states, when given sample access to those states. We also show that this sample-based Hamiltonian simulation can be used as the basis of a universal model of quantum computation that requires only partial swap operations and simple single-qubit states
Proximal Interphalangeal Joint Adipofascial Flap (PIPJAF) Resurfacing Improves the Active Motion of the Proximal Interphalangeal Joint after Contracture Release
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