How Do Students Select Courses in a Liberal Arts University in Hong Kong:a Mixed-Methods Study

Undergraduate students need to choose different (elective) courses each term. This study examines the Course Selection (CS) decision by undergraduate students at a liberal arts university in Hong Kong. It suggests the use of Social Cognitive Theory (SCT) with CS. In addition, this study tries to compare the CS decisions of local (Hong Kong) students with those of mainland (Chinese) students. It builds a 5-factor model ((1) degree of concern about assessment methods, (2) instructor-related issues, (3) interest and career effects, (4) demanding courses and (5) weighting of assessments) using factor analysis and found that Factors 1, 2, 3 and 4 are statistically different between local and mainland students. Using qualitative analysis, themes are identified concerning CS (mainland students: (1) prefer an interesting course, but academic results are a prerequisite; (2) prefer certain qualities of the instructor, but this is not a decisive factor; (3) prefer to balance workload and individual assessment rather than conducting group projects; (4) prefer to have daytime classes and no days off; (5) take advice from peers but make their own decisions; and (6) prefer courses not to have SL elements and local students: (1) regard interest as their top priority; (2) prefer certain qualities/skills of the instructor; (3) are neutral regarding workload but prefer certain assessment methods; (4) have no preference regarding class time but wish to have a day off; (5) are minimally influenced by peers; and (6) dislike Service Learning). Two new factors emerged in this study, and they are (1) the day/time of courses and (2) service-learning elements. This study fills the research gap using a mixed-methods approach provides evidence to support the findings from previous studies and gives insights into the field of CS in the undergraduate context

Supernova-like explosion of massive rotating stars from disks surrounding a black hole

We perform a new general-relativistic viscous-radiation hydrodynamics simulation for supernova-like explosion associated with stellar core collapse of rotating massive stars to a system of a black hole and a massive torus paying particular attention to large-mass progenitor stars with the zero-age main-sequence mass of $M_\mathrm{ZAMS}=$20, 35, and 45$M_\odot$ of Ref.~\cite{Aguilera-Dena2020oct}. Assuming that a black hole is formed in a short timescale after the onset of the stellar collapse, the new simulations are started from initial data of a spinning black hole and infalling matter that self-consistently satisfy the constraint equations of general relativity. It is found that with a reasonable size of the viscous parameter, the supernova-like explosion is driven by the viscous heating effect in the torus around the black hole irrespective of the progenitor mass. The typical explosion energy and ejecta mass for the large-mass cases ($M_\mathrm{ZAMS}=35$ and $45M_\odot$) are $\sim 10^{52}$ erg and $\sim 5M_\odot$, respectively, with $^{56}$Ni mass larger than $0.15M_\odot$. These are consistent with the observational data of stripped-envelope and high-energy supernovae such as broad-lined type Ic supernovae. This indicates that rotating stellar collapses of massive stars to a black hole surrounded by a massive torus can be a central engine for high-energy supernovae. By artificially varying the angular velocity of the initial data, we explore the dependence of the explosion energy and ejecta mass on the initial angular momentum and find that the large explosion energy $\sim 10^{52}$ erg and large $^{56}$Ni mass $\geq 0.15M_\odot$ are possible only when a large-mass compact torus with mass $\gtrsim 1M_\odot$ is formed.Comment: 20 pages, 11 figures, submitted to PR

Novel impeller design for stem cell bioprocessing and its application in hMSC stirred-tank bioreactor cultures

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Toward a Millimeter-Scale Tendon-Driven Continuum Wrist with Integrated Gripper for Microsurgical Applications

Microsurgery is a particularly impactful yet challenging form of surgery. Robot assisted microsurgery has the potential to improve surgical dexterity and enable precise operation on such small scales in ways not previously possible. Intraocular microsurgery is a particularly challenging domain in part due to the lack of dexterity that is achievable with rigid instruments inserted through the eye. In this work, we present a new design for a millimeter-scale, dexterous wrist intended for microsurgery applications. The wrist is created via a state-of-the-art two-photon-polymerization (2PP) microfabrication technique, enabling the wrist to be constructed of flexible material with complex internal geometries and critical features at the micron-scale. The wrist features a square cross section with side length of 1.25 mm and total length of 3.75 mm. The wrist has three tendons routed down its length which, when actuated by small-scale linear actuators, enable bending in any plane. We present an integrated gripper actuated by a fourth tendon routed down the center of the robot. We evaluate the wrist and gripper by characterizing its bend-angle. We achieve more than 90 degrees bending in both axes. We demonstrate out of plane bending as well as the robot's ability to grip while actuated. Our integrated gripper/tendon-driven continuum robot design and meso-scale assembly techniques have the potential to enable small-scale wrists with more dexterity than has been previously demonstrated. Such a wrist could improve surgeon capabilities during teleoperation with the potential to improve patient outcomes in a variety of surgical applications, including intraocular surgery.Comment: 2 pages, 3 figures, submitted to the 2023 Hamlyn Symposium on Medical Robotics conferenc

Binary neutron star mergers in massive scalar-tensor theory: Quasi-equilibrium states and dynamical enhancement of the scalarization

We study quasi-equilibrium sequences of binary neutron stars in the framework of Damour-Esposito-Farese-type scalar-tensor theory of gravity with a massive scalar field, paying particular attention to the case where neutron stars are already spontaneously scalarized at distant orbits, i.e., in the high coupling constant case. Although scalar effects are largely quenched when the separation $a$ is $\gtrsim 3$--$6$ times of the Compton length-scale that is defined by the scalar mass, we show that the interaction between the scalar fields of the two neutron stars generates a scalar cloud surrounding the binary at the price of orbital energy when $a \lesssim 3$--$6$ times of the Compton length-scale. This enables us to constrain the scalar mass $m_\phi$ from gravitational-wave observations of binary neutron star mergers by inspecting the dephasing due to such phenomenon. In particular, the event GW170817 is suggestive of a constraint of $m_\phi \gtrsim 10^{-11}$ eV and the coupling strength should be mild if the neutron stars in this system were spontaneously scalarized.Comment: 14 pages, 8 figures, 1 table. Submitted to PR

99 problems but a riff ain't one : How sampling helps copyright promote originality

This legal policy thesis asks: Is sampling so inconsistent with copyright that it warrants a unique system? Sampling is the musical practice of arranging new recordings from existing recordings. Often, it conflicts with copyright, a legal system that aims to encourage progress and innovation, primarily by granting exclusive rights as incentives to create and distribute original works. Two countervailing positions in existing literature articulate the conflict between sampling and copyright. The first views sampling as an appropriative practice that subverts copyright safeguards against unauthorised copying and adaptation. If this is true, then appropriation art cannot be reconciled with copyright law in any stable, lasting or meaningful manner. The second views copyright as an excessive restraint on creativity, a leash on artists. Scholars holding this position point to copyright's longstanding discrimination against sampling, evident from US copyright cases restricting 1990s hip-hop artists and admonishing one sampling artist with biblical commandment: 'Thou shalt not steal'. This thesis argues that sampling can align with the purpose of copyright to encourage progress and innovation. It shows how sampling is consistent with originality, the core concept that separates the copyright wheat from the unprotected chaff. Originality calls not for the conjuring of material from thin air, but rather the rearrangement of prior works, genres and conventions. By locating rearrangement at the heart of originality, we can see that sampling can contribute to the body of original works and therefore the purpose of copyright. In doing so, this thesis shows that sampling conflicts with the operation of copyright, as expressed in international treaty, national laws and industry conventions. While amending the operation of copyright is difficult, it is possible and indeed desirable to reform copyright to encourage rearrangement, not because it enables sampling, but because it promotes originality. Building on the concept that the rearrangement of past material is the foundation of originality, this thesis explains two potential policy responses to promote originality. Encouraging transformative use, as a conceptual foundation for fair use exceptions, can promote the rearrangement of existing original works into new original works. Likewise, ex post monitoring, as an alternative to ex ante licensing, can enable tolerated uses, incremental originality and distributed innovation at the scale of digital platforms