Excess Returns in the Hong Kong Commercial Real Estate Market

This study examines the existence of excess returns of the office, retail and industrial real estate sectors in Hong Kong using time series of both valuations and transaction prices. The analysis covers the period from 1980 to 1995. If valuations are an accurate reflection of transaction prices then excess returns, if they exits, should be detected in both series. Our findings confirm that excess returns can be detected in both valuation and transaction-based series. They are not, however, persistent although there appear to be greater opportunities for earning excess returns in the office sector.

Past and Future Sources of Real Estate Returns in Hong Kong

Historical commercial real estate returns are attributed to three fundamental factors: initial current yield, growth in net operating income, and changes in going-in versus going-out capitalization rates (i.e., pricing movements). Separating returns into these three factors appears to provide more insightful information than the traditionally reported income and appreciation returns. Using this three-factor model, historical real returns and inflation pass-through rates are estimated for each major type of real estate (residential A/B/C, residential D/E, office, retail, industrial).

Quantum Convolutional Error Correcting Codes

I report two general methods to construct quantum convolutional codes for $N$-state quantum systems. Using these general methods, I construct a quantum convolutional code of rate 1/4, which can correct one quantum error for every eight consecutive quantum registers.Comment: Minor revisions and clarifications. To appear in Phys. Rev.

Direct CP violation in two-body hadronic charmed meson decays

Motivated by the recent observation of CP violation in the charm sector by LHCb, we study direct CP asymmetries in the standard model (SM) for the singly Cabibbo-suppressed two-body hadronic decays of charmed mesons using the topological-diagram approach. In this approach, the magnitude and the phase of topological weak annihilation amplitudes which arise mainly from final-state rescattering can be extracted from the data. Consequently, direct CP asymmetry $a_{dir}^{\rm (tree)}$ at tree level can be reliably estimated. In general, it lies in the range $10^{-4}<a_{dir}^{\rm (tree)}<10^{-3}$. Short-distance QCD penguins and penguin annihilation are calculated using QCD factorization. Their effects are generally small, especially for $D\to VP$ modes. Since weak penguin annihilation receives long-distance contributions from the color-allowed tree amplitude followed by final-state rescattering, it is expected to give the dominant contribution to the direct CP violation in the decays $D^0\to K^+K^-$ and $D^0\to \pi^+\pi^-$ in which $a_{dir}^{\rm (tree)}$ is absent. The maximal $\Delta a_{CP}^{\rm dir}$, the direct CP asymmetry difference between the above-mentioned two modes, allowed in the SM is around -0.25%, more than $2\sigma$ away from the current world average of $-(0.645\pm 0.180)$.Comment: 19 pages, 2 figures; typos correcte

Quantum Convolutional Error Correction Codes

I report two general methods to construct quantum convolutional codes for quantum registers with internal $N$ states. Using one of these methods, I construct a quantum convolutional code of rate 1/4 which is able to correct one general quantum error for every eight consecutive quantum registers.Comment: To be reported in the 1st NASA Conf. on Quantum Comp., uses llncs.sty, 12 page

A Meta-narrative Review of Textured Implants and Associated Lymphoma Risks

In 2011, the Food and Drug Administration (FDA) identified that breast implants are associated with breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). Until 2022, a total of 1130 cases were globally recorded (Health, 2021). Even though researchers are attempting to determine the risks, the accurate etiology has not been determined yet. Comparisons of previous published works are widespread in different potential causes. Hence, we aim to focus on defining how different implants link to BIA-ALCL, especially smooth and textured implants. The review follows the meta-narrative approach with the Pubmed database (2018- now) to collect, combine, and contrast data. All the articles focus on the correlation between the texture of breast implants and BIA-ALCL. The 5 selected studies highlighted similarities and differences to find gaps, limitations among articles and investigate answers for new findings. Classification systems for implant surfaces are divided into groups based on texturing, the parameters of surface area, and bacteria growth. There have been no confirmed cases of BIA-ALCL in patients who have received only smooth breast implants while evidence has reflected textured surface links to the risk of this cancer. Intermediate and high textured surfaces are 10 times higher that links to ALCL than low-surface-area texture (Siltex). Silimed polyurethane, measured as surface grade 4, carries the highest surface area and surface roughness and has been demonstrated to have significantly higher rates of bacterial growth. Without a uniform definition, using the same terms (eg, microtexture and macrotexture) in multiple contexts causes difficulties to compare risks for BIA-ALCLhttps://openworks.mdanderson.org/rmps/1001/thumbnail.jp

Susceptibility inhomogeneity and non-Fermi liquid behavior in UCu_{5-x}Pt_x

Transverse-field muSR shifts and relaxation rates have been measured in the non-Fermi liquid (NFL) alloy system UCu_{5-x}Pt_x, x = 1.0, 1.5, and 2.5. At low temperatures the fractional spread in Knight shifts delta K/K approx deltachi/chi is gtrsim 2 for x = 1, but is only half this value for x = 1.5 and 2.5. In a disorder-driven scenario where the NFL behavior is due to a broadly distributed (Kondo or Griffiths-phase cluster) characteristic energy E, our results indicate that delta E/E_{rm av} approx (delta K/K)_{T=0} is similar for UCu_{5-x}Pd_x (x = 1 and 1.5) and UCu_4Pt, but is reduced for UCu_{5-x}Pt_x, x = 1.5 and 2.5. This reduction is due to a marked increase of E with increasing x; the spread delta E is found to be roughly independent of x. Our results correlate with the observed suppression of other NFL anomalies for x > 1 in UCu_{5-x}Pt_x but not in UCu_{5-x}Pd_x, and are further evidence for the importance of disorder in the NFL behavior of both these alloy systems.Comment: 4 pages, 2 figures, submitted to 10th International Conference on Muon Spin Rotation, Relaxation, and Resonance, Oxford, UK, August 200

Dynamics of a suspended nanowire driven by an ac Josephson current in an inhomogeneous magnetic field

We consider a voltage-biased nanoelectromechanical Josephson junction, where a suspended nanowire forms a superconducting weak-link, in an inhomogeneous magnetic field. We show that a nonlinear coupling between the Josephson current and the magnetic field generates a Laplace force that induces a whirling motion of the nanowire. By performing an analytical and a numerical analysis, we demonstrate that at resonance, the amplitude-phase dynamics of the whirling movement present different regimes depending on the degree of inhomogeneity of the magnetic field: time independent, periodic and chaotic. Transitions between these regimes are also discussed.Comment: 7 pages, 5 figure

Observations of meteor-head echoes using the Jicamarca 50 MHz radar in interferometer mode

International audienceWe present results of recent observations of meteor-head echoes obtained with the high-power large-aperture Jicamarca 50 MHz radar (11.95° S, 76.87° W) in an interferometric mode. The large power-aperture of the system allows us to record more than 3000 meteors per hour in the small volume subtended by the 1° antenna beam, albeit when the cluttering equatorial electrojet (EEJ) echoes are not present or are very weak. The interferometry arrangement allows the determination of the radiant (trajectory) and speed of each meteor. It is found that the radiant distribution of all detected meteors is concentrated in relative small angles centered around the Earth's Apex as it transients over the Jicamarca sky, i.e. around the corresponding Earth heading for the particular observational day and time, for all seasons observed so far. The dispersion around the Apex is ~18° in a direction transverse to the Ecliptic plane and only 8.5° in heliocentric longitude in the Ecliptic plane both in the Earth inertial frame of reference. No appreciable interannual variability has been observed. Moreover, no population related to the optical (larger meteors) Leonid showers of 1998?2002 is found, in agreement with other large power-aperture radar observations. A novel cross-correlation detection technique (adaptive match-filtering) is used in combination with a 13 baud Barker phase-code. The technique allows us to get good range resolution (0.75 km) without any sensitivity deterioration for the same average power, compared to the non-coded long pulse scheme used at other radars. The matching Doppler shift provides an estimation of the velocity within a pulse with the same accuracy as if a non-coded pulse of the same length had been used. The velocity distribution of the meteors is centered around 60 km s?1 corresponding to velocities slightly under the solar escape velocity (72 km s?1). Less than 8% of the velocities correspond to interstellar speeds. Higher relative velocity accuracy is obtained by cross-correlating the echoes from pulse-to-pulse, albeit with an ambiguous velocity displacement which cannot be resolved with the current observing technique. This higher relative accuracy allows the precise measurement of the deceleration of the meteors as they enter the atmosphere. In addition, an independent radial velocity is determined from the derivative of the instantaneous position. Other statistical distributions of interest are also presented

Should Children Use Mobile Phones?

Should children be allowed to use mobile phones? Parents have been receiving mixed messages from health authorities, some of whom recommend that children limit their use of mobile phones on precautionary health grounds. Other health agencies make no such recommendation. Given the enormous popularity of mobile phones with children—indeed, in the United Kindom, more than half of all seven to 16 year-olds own a mobile phone—parents may be understandably confused and worried by such conflicting advice