The Feasibility of Cuban Market Economy: A Comparison with Vietnam

In spite of the difficulties incurred by its people, Cuba has maintained a centrally planned economy with single party system. On the contrary, Vietnam has introduced a market economy under communist rule, and succeeded in generally improving living standards. The factors that contributed to the introduction of Vietnamese-style reforms are (1) severe economic crisis, (2) demonstration effects from neighboring countries, (3) poor social policy, (4) initiatives by ex-conservative leader/s, and (5) weak state capacity. The conditions to sustain high economic growth are (1) social sectors familiar with capitalist economics, (2) abundant labor forces with relatively low labor cost, and (3) investment by exiles. This paper analyzes to what extent Cuba meets these conditions.Cuba, Vietnam, Transition to market economy, Economic policy, Socialism, Economic crisis, Social policy, Economic reform, State capacity, governance, development strategy

Near-Infrared Colours of Active Galactic Nuclei

We propose near-infrared colour selection criteria to extract Active Galactic Nuclei (AGNs) using the near-infrared Colour-Colour Diagram (CCD) and predict near-infrared colour evolution with respect to redshift. First, we cross-identify two AGN catalogues with the 2MASS Point Source Catalogue, and confirm both the loci of quasars/AGNs in the near-infrared CCD and redshift-colour relations. In the CCD, the loci of over 70 - 80% of AGNs can be distinguished from the stellar locus. To examine the colours of quasars, we simulate near-infrared colours using Hyperz code. Assuming a realistic quasar SED, we derive simulated near-infrared colours of quasars with redshift (up to z ~ 11). The simulated colours can reproduce not only the redshift-colour relations but also the loci of quasars/AGNs in the near-infrared CCD. We finally discuss the possibility of contamination by other types of objects. We compare the locus of AGNs with the other four types of objects (namely, microquasars, CVs, LMXBs, and MYSOs) which have a radiation mechanism similar to that of AGNs. In the near-infrared CCD, each type of object is located at a position similar to the stellar locus. Accordingly, it is highly probable that the four types of objects can be distinguished on the basis of the locus in a near-infrared CCD. We additionally consider contamination by distant normal galaxies. The near-infrared colours of several types of galaxies are also simulated using the Hyperz code. Although galaxies with z ~ 1 have near-infrared colours similar to those of AGNs, these galaxies are unlikely to be detected because they are very faint. In other words, few galaxies should contaminate the locus of AGNs in the near-infrared CCD. Consequently, we can extract reliable AGN candidates on the basis of the near-infrared CCD.Comment: 7 pages, 6 figures, Accepted for publication in A&

Cuba's social policy after the disintegration of the Soviet Union -- social development as legitimacy of regime and its economy effectiveness

Since the disintegration of the Soviet Union, Cuba has experienced a severe economic crisis, and the country's social policy has played an important role in showing the people a raison-d'etre for the revolution. This role has become even stronger in recent years, as internal and external actors demand political reforms and economic liberalization. This article first examines the Cuban government's use of social development to counter the demands for changes. It then looks at the extent that government social policy contributes economically to improving the Cuban living standard. The article demonstrates empirically how the leadership emphasizes their social accomplishments whenever demands for change come, and then shows that after the suspension of Soviet aid, Cuban social policy has been able to provide services mainly by relying on human capital and reducing quality materially because of the shortage of foreign reserves. This has limited the economic effectiveness of the services.Cuba, Social security, Social development, Social policy

Masses of vector bosons in two-color dense QCD based on the hidden local symmetry

We construct a low energy effective Lagrangian for the two-color QCD including the "vector" bosons (mesons with J^P=1^- and diquark baryons with J^P=1^+) in addition to the pseudo Nambu-Goldstone bosons with a degenerate mass M_\pi (mesons with J^P=0^- and baryons with J^P=0^+) based on the chiral symmetry breaking pattern of SU(2N_f) \to Sp(2N_f) in the framework of the hidden local symmetry. We investigate the dependence of the "vector" boson masses on the baryon number density \mu_B. We show that the \mu_B-dependence signals the phase transition of U(1)_B breaking. We find that it gives information about mixing among "vector" bosons: e.g. the mass difference between \rho and \omega mesons is proportional to the mixing strength between the diquark baryon with J^P=1^+ and the anti-baryon. We discuss the comparison with lattice data for two-color QCD at finite density.Comment: 24 pages, 5 figure

Discovery of Extremely Large-Amplitude Quasi-Periodic Photometric Variability in WC9-Type Wolf-Rayet Binary, WR 104

We discovered that the Wolf-Rayet (WR)+OB star binary, WR 104, renowned for its associated "dusty pinwheel nebula" recently spatially resolved with infrared interferometry, exhibits strong quasi-periodic optical variations with a full amplitude of 2.7 mag. Such a large-amplitude, continuous variation has been unprecedented in a WR star. The optical quasi-period (~241 d) is in almost perfect agreement with the interferometric period (243.5+/-3 d). The remarkable agreement of the dominant period in optical variability with the orbital period supports that the strongly varying dust obscuration is physically related to the binary motion, rather than sporadic dust-forming episodes. Considering the low orbital inclination (11+/-7 deg) and the nearly circular orbit inferred from the interferometric observations, the strongly variable line-of-sight extinction suggests that the highly structured extinction can be being formed via an ejection of dust in the direction of the binary rotation axis. Another viable explanation is that the three-dimensional structure of the shock front, itself is the obscuring body. Depending on the geometry, the dusty shock front near the conjunction phase of the binary can completely obscure the inner WR-star wind and the OB star, which can explain the amplitude of optical fading and the past observation of remarkable spectral variation.Comment: 5 pages, 4 figures, to appear in PASJ (Letters), using an alternative style fil

Deep Transient Optical Fading in the WC9 Star WR 106

We discovered that the WR9-type star WR 106 (HDE 313643) underwent a deep episodic fading in 2000. The depth of the fading (dV ~ 2.9 mag) surpassed those of all known similar "eclipse-like" fadings in WR stars. This fading episode was likely to be produced by a line-of-sight episodic dust formation rather than a periodic enhancement of dust production in the WR-star wind during the passage of the companion star though an elliptical orbit. The overall 2000 episode was composed of at least two distinct fadings. These individual fadings seem to more support that the initial dust formation triggered a second dust formation, or that the two independent dust formations occurred by the same triggering mechanism rather than a stepwise dust formation. We also discuss on phenomenological similarity of the present fading with the double fading of R CrB observed in 1999-2000.Comment: 3 pages, 4 figures, to appear in Astron. Astrophys. (Letters

Recurrent Nova IM Normae

We detected the second historical outburst of the 1920 nova IM Nor. Accurate astrometry of the outbursting object revealed the true quiescent counterpart having a magnitude of R=17.0 mag and B=18.0 mag. We show that the quiescent counterpart shows a noticeable variation. From the comparison of light curves and spectroscopic signatures, we propose that IM Nor and CI Aql comprise a new class of recurrent novae bearing some characteristics similar to those of classical novae. We interpret that the noticeable quiescent variation can be a result of either high orbital inclination, which may be also responsible for the low quiescent brightness, or the presence of high/low states. If the second possibility is confirmed by future observations, IM Nor becomes the first recurrent nova showing state changes in quiescence. Such state changes may provide a missing link between recurrent novae and supersoft X-ray sources.Comment: 4 pages, 3 figures, submitted to Astronomy and Astrophysics Letter