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Dengue fever (DF) and leptospirosis are serious public problems in tropical regions, especially in Manila, the Philippines. In attempting to understand the causes of DF and leptospirosis seasonality, meteorological factors have been suspected, but quantitative correlation between seasonality and meteorological factors has not been fully investigated. In this study, we investigated correlation of temporal patterns of reported numbers of laboratory-confirmed cases of both DF and leptospirosis with meteorological conditions (temperature, relative humidity, rainfall) in Manila. We used time-series analysis combined with spectral analysis and the least squares method. A 1-year cycle explained underlying variations of DF, leptospirosis and meteorological data. There was a peak of the 1-year cycle in temperature during May, followed by maxima in rainfall, relative humidity and number of laboratory-confirmed DF and leptospirosis cases. This result suggests that DF and leptospirosis epidemics are correlated not only with rainfall but also relative humidity and temperature in the Philippines. Quantifying the correlation of DF and leptospirosis infections with meteorological conditions may prove useful in predicting DF and leptospirosis epidemics, and health services should plan accordingly.
Looking for and studying very distant galaxy clusters, clusters at z > 1, are one of the prime subjects of the modern observational cosmology. If the metallicity of the hot intra-cluster medium in very distant galaxy clusters is measured for example, it provides fruitful informations for us to understand the formation and evolution of galaxies. However, difficulty of the study is that there is few confirmed very distant galaxy clusters yet. We first have to search for very distant clusters but it requires very deep observations. A random selection of sky is not practical. We have to select the sky. In this article, it is demonstrated that missing lens problem has close connection with very distant cluster of galaxies and dark lens searches could open a new window for studying very distant cluster of galaxies.
Although the Great Basin of North America has produced some of the most robust and ancient fiber artifact assemblages in the world, many were recovered with poor chronological controls. Consequently, this class of artifacts has seldom been effectively incorporated into general discussions of early chronological and cultural patterns. In recent years, the Great Basin Textile Dating Project has accumulated direct AMS dates on textiles (bags, sandals, mats, cordage, and basketry) from dry caves in the Great Basin, particularly in the northern and western areas. We focus here on the terminal Pleistocene/early Holocene, to identify chronological patterns in this class of artifacts and to evaluate Adovasio’s characterization of the region’s earliest basketry as simple and undecorated. New AMS dates now suggest that the region’s earliest people had sophisticated textile traditions that incorporated numerous decorative elaborations. Some distinctive structures, including Fort Rock sandals and weft-faced plaited textiles, have limited early temporal ranges and may serve as diagnostic indicators for terminal Pleistocene/early Holocene times. Other basketry forms and structures that appear by about 9000 cal B.P. persist into the historic period, suggesting a stronger thread of continuity (especially in the north) from this time than is apparent in lithic traditions
Seyfert galaxies often have extended emission line regions around their nucleus. We started an observation program of optical tridimensional spectroscopy for circumnuclear regions of nearby Seyfert galaxies to investigate the ionization source of the gas of just vicinity(typically several hundred pc) of nucleus.
A narrow-band imaging observation of the Seyfert galaxy NGC1068 was made in the Fabry-Perot mode of the Kyoto 3D Spectrograph attached to the 188cm telescope of the Okayama Astrophysical Observatory. We observed at wavelengths of Hα, [S ii]λ6716, [S ii]λ6731 and adjacent continua of the respective lines with a “tunable filter”, i.e. a gap-scanning etalon with a spectral resolution of 20 Å.
The Kyoto 3-D Spectrograph was commissioned successfully at the 188-cm telescope of the Okayama Astrophysical Observatory in the spring of 1996. This instrument has four distinct modes (Ohtani et al. 1994): (1) narrow-band imager, which is an ordinary focal-reducer camera; (2) Spectro-NebulaGraph (long-slit spectrograph; Kosugi et al. 1995); (3) imaging Fabry-Perot interferometer, using either of two Fabry-Perot etalons from Queensgate Instruments (a tunable filter with R = 300 and another with R = 7000 for velocity-field observations. Broad-band (400–700 nm) coatings are deposited on both etalons. During observations, the etalon temperature is stabilized within 0.5°C); and (4) integral-field spectrograph of the TIGER-type (Bacon et al. 1995). In this mode, the spectra of 7 × 11 objects can be recorded simultaneously, along with 7 × 2 spectra of the sky 4′ away. The spatial resolution is 1″.3 and the field of view is 9″ × 14″.
Variability of the light curves of the short-period eclipsing binary system GR Tau (, almost-contact binary) is studied. It is found that GR Tau experienced both the state which is characterized by asymmetric light curves and the state characterized by symmetrical light curves.
Hockett et al. 's (2014) comment argues two points: (1) the Nicholarsen Cache does not contain both dart and arrow points;, and (2) the “early“ Elko points in our sample are Large Side-notched points. We appreciate their reanalysis of the Nicholarsen Cache points using a different approach, which leads them to the same conclusion made in our original article. Whereas we concede that one of the Elko points is difficult to classify and could be viewed as a Large Side-notched point, we find no evidence that the other specimen is anything but an Elko point directly dated to the middle Holocene.
This study considers the convective-type instability of the near-field flow of a planar, pure thermal plume with a finite area source. Previous studies revealed the existence of an off-axis thermal boundary-layer instability, driving a puffing instability in the central ascending column, and qualitatively showed correlations between instabilities in these two flow regions. This paper extends the analysis to examine the effect of Prandtl number on transitional near-field behaviours and reports on the stability characteristics of a near-field, pure thermal plume based on a direct stability analysis. The variations in flow behaviours in response to symmetric and asymmetric disturbances suggest the existence of coupled instability mechanisms in the off-axis thermal boundary layer and the central ascending column.
Typological cross-dating is the primary means by which archaeological sites are placed into chronological frameworks. This approach relies on the assumption that artifacts at undated sites—usually projectile points—are coeval with similar artifacts found at Other, dated sites. While typological cross-dating is necessary in regions dominated by open-air lithic scatters, the approach can be problematic when undated and dated sites are separated by significant distances. Here, we present radiocarbon dates on projectile points with organic hafting material still attached or found within organic storage bags. Our results provide unequivocal ages for various morphological projectile point types at several Great Basin locales and should be useful to researchers seeking local age estimates for those point types, which often involves relying on chronological data from more distant sites. The results also highlight potential issues with uncritically applying typological cross-dating using typologies based on metric attributes, and in two cases, suggest the need to revise the age ranges for certain point styles in the western Great Basin.
Ferritchromite is rarely reported in forearc mantle peridotites. This contribution describes ferritchromite alteration and zoned Cr-spinel in serpentinites from the Rio San Juan Complex in the Dominican Republic. These rocks originated from the forearc mantle and protruded along lithosphere-scale faults in the mid Eocene. The cores of the Cr-spinel grains have Cr# ratios [i.e.atomic Cr/(Cr + Al)] between 0.48 and 0.66; such values are relatively high and are considered to represent primary compositions. Relatively high Zn contents in the grain cores (0.46 c 0.95 wt.% ZnO) are also thought to be primary; they reflect exceptionally cool conditions in the northern Caribbean forearc mantle. A progressive change in the zoning of Cr-spinel is recorded in the samples. Weakly zoned grains of Cr-spinel have rims with lower Mg# ratios [i.e.atomic Mg/(Mg + Fe2+)] and slightly higher Cr# ratios than the cores. More strongly zoned grains of Cr-spinel, in addition to low Mg# and high Cr# in their rims, have a marked increase in Fe3+# [i.e.Fe3+/(Fe3+ + Al + Cr)] of up to 0.35 in their rims and are partially coated by Mg-rich chlorite. All grains show core-to-rim decreases in their Zn content and increases in Ti, Mn and V. The association with Mg-rich chlorite and the compositional zoning are reminiscent of those reported for ferritchromite. Ferritchromite (with Fe3+# >0.5) is common in ultramafic rocks in amphibolite-grade terranes; however, the serpentinite samples described herein show little evidence of high-grade metamorphism. The lowtemperature serpentine-group mineral lizardite is dominant and high-temperature antigorite is either very rare or absent; other high-temperature minerals, such as talc, tremolite and cummingtonite, are trace constituents. The observed zoning in the Cr-spinel is thought to represent 'immature' ferritchromite, probably formed in response to a short-lived thermal event. This event appears to have been on too short a timescale to produce either proper ferritchromite or significant quantities of high-temperature minerals. It may be related to the emplacement of the nearby Rio Boba Intrusion, or the upward protrusion of the serpentinites along the lithosphere-scale Septentrional fault zone from the base of the mantle wedge through its hotter interior. We suggest that such alteration is rare in forearc serpentinites because they are not commonly heated during exhumation along the plane of subduction. This work demonstrates that Cr-spinel compositions can be modified by relatively low-grade metamorphism.
Using the Subaru telescope and its FOCAS spectrograph in multi-object mode, we have obtained spectra of a selection of bright PNs in two galaxies: the Virgo giant elliptical M 60 (NGC 4649), and the starburst spiral M 82. We report on individual extinctions, as determined from the Balmer decrement, and also on the intensities of [O III] 4959 and 5007 relative to Hβ.
A super-Chandrasekhar (SC) supernova (SN) has an extremely high luminosity and a slow decline rate of the light curve in the early-phase. We present late-phase observations of the SC SN 2009dc. We find that the optical luminosity a year after maximum is much fainter than that expected from its early luminosity. We attempt to fit the analytic light curve model to the observations using Arnett's rule. The model successfully explains the light curves until 120 days. This suggests that the extremely high luminosity originates from the 56Ni decay. We suggest that the late-phase decline would be caused by dust formation. The existence of strong carbon features in early-phase spectra would support this scenario. We also find a blend of [Ca ii] and [Ni ii] in its late-phase spectrum. This indicates that the calcium is distributed in the inner layer along with nickel and iron. We conclude that the mixing may occur in the inner parts of the ejecta.
We successfully obtained the first optical spectra of the faint light echoes around Cassiopeia A and Tycho Brahe's supernova remnants (SNRs) with FOCAS and the Subaru Telescope. We conclude that Cas A and Tycho's SN 1572 belong to the Type IIb and normal Type Ia supernovae, respectively. Light echo spectra are important in order to obtain further insight into the supernova explosion mechanism of Tycho's SN 1572: how the Type Ia explosion actually proceeds, and whether accretion occurs from a companion or by the merging of two white dwarfs. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. Future light-echo spectra, obtained in different spatial directions of SN 1572, will enable to construct a three-dimensional spectroscopic view of the explosion.
Interlayers of montmorillonite were pillared with TiO2, SiO2 -TiO2 and SiO2-Fe2O3 sols. The pillared structures were thermally stable at least up to 500°C and retained unusually large basal spacings in the range of 24–45Å and surface areas as high as 300–500 m2 /g. The TiO2 pillared clay showed Type IV adsorption isotherm for nitrogen. Although SiO2 -TiO2 and SiO2-Fe2O3 pillared clays had basal spacings much larger than that of TiO2 pillared clay, these mixed oxide pillared clays had small pores and exhibited Type I isotherm. The acidic strength distributions were determined by a titration method using n-butylamine and Hammett indicators. All of the pillared clays had large acidities, but the acidic strength decreased in the following order: TiO2 - SiO 2 » SiO2-Fe2O3 pillared clays. Temperature-programmed desorption (TPD) spectra of ammonia were measured and interpreted in relation to the acidity distribution. Infrared spectra of pyridine adsorbed on TiO2 pillared clay indicated that the acidity predominantly arises from Lewis acid sites.
We have investigated the dielectric properties of the Cr2O3 films using ferromagnetic electrode; (La0.66, Sr0.33)MnO3. The relationships between those properties and their crystallinity also have been investigated. The well crystallized sample was exhibited low leakage current density. Although all samples show capacitance decreasing by applying voltages, the decreasing ratio was the largest on the sample with lowest leakage current density. Since the Cr2O3 film with same leakage current density as that sample using non-magnetic electrode didn't show any capacitance changes by applying voltages, it is suggested that the dielectric properties of Cr2O3 film might be affected by the ferromagnetic film.
A series of systematic trials to improve the light emission efficiency has been made on thin film visible a-SiC LEDs. A wide variety of the approaches, such as a superlattice structure, p-i-n/p-i-n tandem structure, an efficient injection electrode with a wide-gap layer etc., have been done. From the results, two practically available new technologies for bright LEDs have been developed, that is; a) a hot carrier injection structure by inserting a highly- resistive layer between p-and i- or i- and n-layers and b) a wide-gap highly-conductive p-type injector layer prepared by ECR (Electron Cyclotron Resonance) CVD deposition. With these trials, the brightness of yellow LEDs have been increased by more than one order of magnitude to be about 5cd/m2
The degradation mechanism of the Schottky contact of Al/Ti/n-GaAs and Al/Pt/Ti/n-GaAs under the heat treatment of 300°C has been investigated. Barrier height of the Al/Ti/n-GaAs Schottky contact degrades drastically after the heat treatment, in which Ti-Al alloy and Ga out-diffusion have been observed. On the other hand, the barrier height of Al/Pt/Ti/n-GaAs contacts is stable under the heat treatment and, Al-Ti alloying as well as Ga out-diffusion in the metals could not be noticed. From these results, it is presumably concluded that the degradation of the Schottky contacts under the heat treatment is closely correlated with the Ga atom out-diffusion from GaAs surface into the metal films after Al-Ti alloy reach to the GaAs surface. The barrier height reduction after the heat treatment can be explained by the formation of the donor type level at the interface due to the Ga vacancy pile-up arose from the Ga out-diffusion. Pt layer was proved to be an effective barrier suppressing the intermetallic alloying and preventing out-diffusion of Ga.