3,624 research outputs found
Double solid twistor spaces: the case of arbitrary signature
In a recent paper (math.DG/0701278) we constructed a series of new Moishezon
twistor spaces which is a kind of variant of the famous LeBrun twistor spaces.
In this paper we explicitly give projective models of another series of
Moishezon twistor spaces on nCP^2 for arbitrary n>2, which can be regarded as a
generalization of the twistor spaces of a 'double solid type' on 3CP^2 studied
by Kreussler, Kurke, Poon and the author. Similarly to the twistor spaces of
'double solid type' on 3CP^2, projective models of present twistor spaces have
a natural structure of double covering of a CP^2-bundle over CP^1. We
explicitly give a defining polynomial of the branch divisor of the double
covering whose restriction to fibers are degree four. If n>3 these are new
twistor spaces, to the best of the author's knowledge. We also compute the
dimension of the moduli space of these twistor spaces. Differently from
math.DG/0701278, the present investigation is based on analysis of
pluri-(half-)anticanonical systems of the twistor spaces.Comment: 30 pages, 3 figures; v2: title changed (the original title was
"Explicit construction of new Moishezon twistor spaces, II".
Scaling of dynamics with the range of interaction in short-range attractive colloids
We numerically study the dependence of the dynamics on the range of
interaction for the short-range square well potential. We find that,
for small , dynamics scale exactly in the same way as thermodynamics,
both for Newtonian and Brownian microscopic dynamics. For interaction ranges
from a few percent down to the Baxter limit, the relative location of the
attractive glass line and the liquid-gas line does not depend on . This
proves that in this class of potentials, disordered arrested states (gels) can
be generated only as a result of a kinetically arrested phase separation.Comment: 4 pages, 4 figure
Entanglement transformation between sets of bipartite pure quantum states using local operations
Alice and Bob are given an unknown initial state chosen from a set of pure
quantum states. Their task is to transform the initial state to a corresponding
final pure state using local operations only. We prove necessary and sufficient
conditions on the existence of such a transformation. We also provide efficient
algorithms that can quickly rule out the possibility of transforming a set of
initial states to a set of final states.Comment: 19 pages, 1 figure, minor revision, to appear in J.Math.Phy
Diffusive Evolution of Stable and Metastable Phases II: Theory of Non-Equilibrium Behaviour in Colloid-Polymer Mixtures
By analytically solving some simple models of phase-ordering kinetics, we
suggest a mechanism for the onset of non-equilibrium behaviour in
colloid-polymer mixtures. These mixtures can function as models of atomic
systems; their physics therefore impinges on many areas of thermodynamics and
phase-ordering. An exact solution is found for the motion of a single, planar
interface separating a growing phase of uniform high density from a
supersaturated low density phase, whose diffusive depletion drives the
interfacial motion. In addition, an approximate solution is found for the
one-dimensional evolution of two interfaces, separated by a slab of a
metastable phase at intermediate density. The theory predicts a critical
supersaturation of the low-density phase, above which the two interfaces become
unbound and the metastable phase grows ad infinitum. The growth of the stable
phase is suppressed in this regime.Comment: 27 pages, Latex, eps
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Human resource management changes in China: a case study of the banking industry
Change in human resource management (HRM) has attracted attention in a range of management disciplines. Examining the influences on HRM change relates to several areas, including the discussion of convergence and divergence, institutional forces and cultural heritages, as well as HRM transferability and adoption. Evidence supporting these views remains diverse and not complete enough to explain the issues. To address the gap in the literature, the current research conducted an in-depth study of the banking industry in the People's Republic of China (henceforth China). China's entry into the World Trade Organisation (WTO) and its economic reforms have exerted pressures on local Chinese banks (LCBs) while offering business opportunities to foreign-invested banks (FIBs). Two research questions were formulated: (1) to assess if LCBs and FIBs operating in China have changed their HRM practices towards or from each other; and (2) to examine which contextual factors relate to HRM change.
Based on the research findings, changes were observed in both LCBs and FIBs during the period 2000 to 2008 in several HRM areas ("change content"), including resourcing and retention, rewards and performance, and training and development. LCBs used many Western HRM practices. Objective-setting performance management, graduate trainee programme, market-adjusted bonus schemes etc. were introduced due to competition and institutional isomorphism ("change context"). However, some of these changes were implemented for a couple of years but were not successfully carried forward because resistance was felt from employees and organisation inertia restrained LCBs from full absorption of new practices. On the other hand, FIBs transferred many global HRM practices to their local branches. Embedded culture and contingent impediments made neither customisation of global plans nor adoption of local approaches easy.
It is argued that (a) while transfer and adoption of HRM practices was observed, the inter-group change between LCBs and FIBs was much larger and faster than intra-group change between FIBs home and host countries. (b) The change process was not smooth; rather, across-time change was in the form of waves and characterised by delays and oscillations. It is not sure (c) if change outcome would result in LCBs and FIBs having their HRM systems converged towards something similar, formed a hybrid transitionary model, or remained diverge. Finally, (d) firm nationality and firm size had significantly influence on HRM decision, but firm age did not have any change relationship with HRM practices
Using Positive Youth Development Constructs to Design a Drug Education Curriculum for Junior Secondary Students in Hong Kong
This paper outlines the design of a new curriculum for positive youth development (P.A.T.H.S. II) in Hong Kong. The paper discusses the conceptual base for designing a drug-education curriculum for junior-secondary students using four positive youth development constructs—cognitive competence, emotional competence, beliefs in the future, and self-efficacy. The program design is premised on the belief that adolescents do have developmental assets; therefore, the curriculum is designed to develop their psychosocial competencies. The goal of the curriculum is to develop the selfhood of these youths and ultimately achieve the goal of successful adolescent development
Using Positive Youth Development Constructs to Design a Money Management Curriculum for Junior Secondary School Students in Hong Kong
This paper aims to discuss the relationships between the selected positive youth development constructs and the enhancement of Hong Kong junior secondary school students' money management skills, values, and attitudes. Various issues of money management of adolescents are reviewed. These issues include the need for money management programs for adolescents, the content and coverage of an appropriate money management program, and its relationships with the selected positive youth development constructs. The curriculum units for secondary 3 students are taken as examples to illustrate the design of the program. It is believed that promoting cognitive competence, self-efficacy, and spirituality could be an effective way to enhance students' money management skills, values, and attitudes, thus preparing them better for facing the finance-related issues in life
Cost-utility analysis of robotic-assisted radical cystectomy for bladder cancer compared to open radical cystectomy in the United Kingdom
BACKGROUND: Bladder cancer is the tenth most common cancer in the United Kingdom. Currently, open radical cystectomy (ORC) is the gold standard. Due to the risk of complications and a 2.3-8% mortality rate1, there is growing interest in the use of robot-assisted radical cystectomy (RARC). The aim of this study is to perform a cost-utility analysis, comparing RARC to ORC for bladder cancer patients from the perspective of the National Health Service England. METHODS: A three-stage decision tree: surgery, post-surgery transfusions and complications, in a 90-day time horizon, was produced to simulate possible pathways of patients. The incremental cost-effectiveness ratio (ICER) was calculated based on data derived from current literature. Multiple univariate sensitivity analysis was carried out to evaluate influences of varying costs of RARC and ORC on the ICER. RESULTS: The ICER for RARC compared to ORC resulted in £25,536/QALY. At the lower threshold of £20,000/QALY, RARC resulted in a negative NMB (£-4,843.32) and at the upper threshold of £30,000/QALY, a positive NMB (£624.61) compared to ORC. Threshold analysis showed that the intervention costs of £13,497 and £14,403 are met at the lower and upper threshold respectively. The univariate sensitivity analysis showed that the intervention costs of RARC or ORC, and the probabilities of complications, had the greatest impact on the ICER. CONCLUSION: As the resultant ICER did not fall below the £20,000/QALY threshold, our study did not provide a definitive recommendation for RARC for bladder cancer. Negative values for the NMB at the lower threshold indicated the intervention was not feasible from a cost perspective. At the upper threshold of £30,000/QALY, this situation was reversed. The intervention became cost-effective. Therefore, further research is needed to justify the intervention
Induced Metric And Matrix Inequalities On Unitary Matrices
Recently, Chau [Quant. Inform. & Comp. 11, 721 (2011)] showed that one can
define certain metrics and pseudo-metrics on U(n), the group of all
unitary matrices, based on the arguments of the eigenvalues of the unitary
matrices. More importantly, these metrics and pseudo-metrics have quantum
information theoretical meanings. So it is instructive to study this kind of
metrics and pseudo-metrics on U(n). Here we show that any symmetric norm on
induces a metric on U(n). Furthermore, using the same
technique, we prove an inequality concerning the eigenvalues of a product of
two unitary matrices which generalizes a few inequalities obtained earlier by
Chau [arXiv:1006.3614v1].Comment: 6 pages, extensively rewritten with an earlier error fixed. It
generalizes and simplifies the mathematical results concerning certain matrix
inequalities originally reported in arXiv:1006.3614v1. To appear in J.Phys.
An H5N1-based matrix protein 2 ectodomain tetrameric peptide vaccine provides cross-protection against lethal infection with H7N9 influenza virus
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