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Boring sponges are an important component of bioeroder assemblages in tropical coral reefs. They are considered as a potential threat for coral reef health, and the increase of dead corals is expected to promote their abundance. The relationship between the availability of dead coral substrata and the development of boring sponge assemblages was evaluated during El Niño 2015–16 at five reefs from Zihuatanejo, Guerrero, Mexico. Environment and substrate quality were assessed. Overall, environment conditions remained normal in relation to previous studies in the area. Only water temperature showed unusually high records at all sites and coincided with bleaching and mortality of corals, possibly caused by the effects of the El Niño event. Abundance of boring sponges in dead corals and coral rubble was lower than during previous studies. Although sponge abundance was not directly related to cover of both dead corals and coral rubble, cover of dead corals showed a high correlation with the variation in the structure of sponge assemblages across sites. Cliona vermifera dominated sponge assemblages at all sites, and its abundance was high under conditions of high cover of live corals and low cover of bleached corals. Since overall sponge abundance responded in a similar way, these results suggest that boring sponge assemblages dominated by C. vermifera are enhanced by conditions favourable for corals. Our results imply that El Niño events in the Mexican Pacific are not likely to cause immediate population outbreaks of boring sponges.
For optimal application of Nesidiocoris tenuis as a biological control agent, adequate field management and programmed mass rearing are essential. Mathematical models are useful tools for predicting the temperature-dependent developmental rate of the predator. In this study, the linear model and nonlinear models Logan type III, Lactin and Brière were estimated at constant temperatures and validated at alternating temperatures and under field conditions. N. tenuis achieved complete development from egg to adult at constant temperatures between 15 and 35°C with high survivorship (>80%) in the range 18–32°C. The total developmental time decreased from a maximum at 15°C (76.74 d) to a minimum at 33°C (12.67 d) and after that, increased to 35°C (13.98 d). Linear and nonlinear developmental models all had high accuracy (Ra2 >0.86). The maximum developmental rate was obtained between 31.9°C (Logan type III and Brière model for N1) and 35.6°C (for the egg stage in the Brière model). Optimal survival and the highest developmental rate fell within the range 27–30°C. The field validation revealed that the Logan type III and Lactin models offered the best predictions (95.0 and 94.5%, respectively). The data obtained on developmental time and mortality at different temperatures are useful for mass rearing this predator, and the developmental models are valuable for using N. tenuis as a biological control agent.
Lizards of the genus Anolis have been widely studied, however, little is known about the effects of environmental seasonality, food availability and geographic isolation on body condition, growth rate and habitat use of lizards. The existence of an insular and a continental population of Anolis nebulosus (clouded anole), separated by only 0.47 km, represents an ideal opportunity to address this topic. We compared seasonal fluctuations in food availability (arthropod density) for anoles, as well as body condition, growth rate and habitat use in the two populations. Food availability throughout the year was sampled every 2 mo by trapping arthropods at each site. Lizards were also monitored and measured every 2 mo by surveying three quadrats in each site over 2 y giving a total of 30 visits for each quadrat. Results suggested that composition and density of food supply was similar for the two populations. Nevertheless, food supply responded to seasonality of rainfall, with an increase of 1.5 times during the rainy season. Despite similarity in food availability, insular anoles had body condition that was 5–10 times better, with growth rate twice as fast, and used similar perches. The role of predation, and inter- and intraspecific competition are discussed as possible drivers.
This paper offers new quantitative evidence on living standards in Bourbon America through a pioneering study of both wages and heights. Wages were not low, nor were heights short, by the international standards of the period. The living standards of Spanish Americans thus compare favourably with those of other regions of the world, including Europe. As in many parts of the West, one can observe a trend towards the deterioration of real wages in Spanish America at the end of the period. Our findings suggest that the ‘Great Divergence’ in living standards between Spanish America and the developed Western countries might have taken place mainly after independence and that currently available GDP per capita estimates might be too low.
Hippocampal sclerosis (HS) has been recognized as the most commonly encountered pathological substrate of mesial temporal lobe epilepsy (MTLE). The pathological condition was initially described by early neuropathologists based on postmortem material. Studies in familial MTLE are also important for better understanding of the pathogenesis of HS. HS identified by magnetic resonance imaging (MRI) has been associated with poor medical control of seizures. Neurologic examination is usually normal except for facial asymmetry and memory deficits, which are material-specific for the side of ictal onset. Interictal electroencephalogram (EEG) findings in patients with MTLE typically include unilateral or bilaterally independent mesial temporal spikes, best seen with basal derivations. Treatment should start with a first-line antiepileptic drug (AED) in monotherapy, the dose of which is increased until seizure freedom or the occurrence of side effects such as tiredness, dizziness, diploplia, or gait disturbance.
The synthesis of Al2O3-based functional materials having 10 vol. % of fine aluminum or titanium and aluminum-disperse or titanium-dispersed nitride hardened-particles has been explored. Two experimental steps have been set for the synthesis; specifically, sintering of Al2O3-aluminum or Al2O3-titanium powders which were thoroughly mixed under high energy ball-milling, pressureless-sintered at 1400°C during 1 h in argon atmosphere and then for the second step it was induced formation of aluminum nitride or titanium nitride at 500°C during different times (24, 72 and 120 h) by a nitriding process via immersion in ammoniac salts. SEM analyses of the microstructures obtained in nitride bodies were performed in order to know the effect of the ammoniac salts used as nitrating on the microstructure of aluminum or titanium for each studied functional material. It was observed that an aluminum nitride or titanium nitride layer growth from the surface into the bulk and reaches different depth as the nitriding time of the functional material was increased. The use of aluminum or titanium significantly enhanced density level and hardness of the functional materials.
We have carried out a comparison between flat-band transients displayed in metal-oxide-semiconductor (MOS) structures fabricated on several atomic layer deposited (ALD) high-k dielectric films: HfO2, ZrO2, Al2O3, Ta2O5, TiO2, and Gd2O3. The gate voltage as a function of time is recorded while keeping constant the capacitance at the initial flat band condition (CFB). Since samples are in darkness, under no electric fields and no charge-injection conditions, transients must be due to charge trapping of localized states produced by electrons (holes) coming from the semiconductor by tunnelling. The process is assisted by phonons and it is therefore thermally activated. The temperature-transient amplitude relation follows an Arrhenius plot which provides the thermal activation energy of soft-optical phonons. Finally, we describe the dependencies of the flat-band voltage on the setup bias history (accumulation or inversion) and the hysteresis sign (clockwise or counter-clockwise) of the capacitance-voltage (C-V) characteristics of MOS structures.
Brazing is a unique method to permanently join a wide range of materials without oxidation. It has wide commercial application in fabricating components. This paper discusses results regarding the brazing process of 304 stainless steel. The experimental brazing is carried out using a nickel-based (Ni-11Cr-3.5Si-2.25B-3.5Fe) filler alloy. In this process, boron and silicon are incorporated to reduce the melting point, however they form hard and brittle intermetallic compounds with nickel (eutectic phases) which are detrimental to the mechanical properties of brazed joints. This investigation deals with the effects of holding time and brazing temperature on the microstructure of joint and base metal, intermetallic phases formation within the brazed joint as well as measurement of the tensile strength. The results show that a maximum tensile strength of 464 MPa is obtained at 1120°C and 4 h holding time. The shortest holding times will make boron diffuse insufficiently and generate a great deal of brittle boride components.
Composites of M-2.5 mol. % Fullerene C60 composites (where M= Fe or Al) are prepared by mechanical milling and Spark Plasma Sintering (SPS). The SPS technique has been used to consolidate the resulting powders and preserve the massive nanostructure. Results of X-Ray Diffraction and Raman Spectroscopy show that larger milling balls (9.6 mm in diameter) produce transformation of the fullerene phase during mechanical milling. Alternatively smaller milling balls (4.9 mm in diameter) allow retention of the fullerene phase. SEM shows homogeneous powders with different particle sizes depending on milling times. Sintering produces nanostructured composite materials with different reinforcing phases including C60 fullerenes, diamonds and metal carbides. The presence of each phase depends characteristically on the energy input during milling. Transmission Electron Microscopy (TEM) and Raman Spectroscopy show evidence of the spatial distribution and nature of phases. Diamonds and carbides can be identified for the sintered Fe containing composites with a relatively high volume fraction.
This paper attempts to contribute to the ongoing debate on the historical roots of the high economic inequality of contemporary Iberian America. Our approach, which is basically empirical, departs from the mainstream scholarship. We show new data on wages and heights in several viceroyalties that (1) suggest relatively medium-to-high levels of material welfare among the commoners in Bourbon Hispanic America; and (2) allow us to build indexes of economic inequality. An international comparison of those indexes casts some doubts on the widely accepted view that Viceroyal America’s economy was exclusively based on extremely unequal or extractive institutions, as it has been popularized by the influential works by Engerman and Sokoloff and Acemoglu et al.
Background: Very few studies have compared the efficacy of individual and group cognitive behaviour therapy (CBT) for the treatment of Obsessive-Compulsive Disorder (OCD) by taking into consideration the change in OCD severity in both the short and long term. Aims: To conduct an open trial of individual versus group CBT for OCD, comparing the clinical and statistically significant changes in severity both at post-treatment and one year later. Method: Forty-two OCD subjects were assigned to individual (n = 18) or group CBT (n = 24, in four groups). Sixteen and 22 subjects completed the treatment in the individual and group conditions, respectively. The Yale-Brown Obsessive Compulsive Scale was recorded at pre-treatment, post-treatment and at the one-year follow-up. Results: At the end of treatment, the clinically significant change was comparable for the two treatment conditions and remained stable at the one-year follow-up. Of the 16 participants who completed the individual CBT treatment, 68.75% were classified as recovered at post-treatment, compared to 40.9% of those receiving group CBT. At follow-up the rate of recovery decreased to 62.5% in individual CBT and to 31.8% in group CBT. Conclusions: Group CBT is effective in decreasing OCD severity. The post-treatment changes were maintained one year later. Nevertheless, these changes were higher in the individual delivery of CBT.
In this paper two characterizations of the Pólya
distribution are obtained when its contagion parameter is
negative. One of them is based on mixtures and the other one is
obtained by characterizing a subfamily of the discrete Pearson
Rosa González-Delgado, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain,
Enrique Pérez, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain,
Guillermo Tenorio-Tagle, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain,
José M. Víchez, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain,
Elena Terlevich, Royal Greenwich Observatory, Madingley Road, Cambridge CB3 0EZ, UK,
Roberto J. Terlevich, Royal Greenwich Observatory, Madingley Road, Cambridge CB3 0EZ, UK,
Eduardo Telles, Royal Greenwich Observatory, Madingley Road, Cambridge CB3 0EZ, UK,
José M. Rodríguez-Espinosa, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain,
Miguel Mas-Hesse, Laboratorio de Astrofísica Espacial y Física Fundamental (LAEFF), Apdo. 50727, 28080 Madrid, Spain,
María Luisa García-Vargas, Depto. Física Teórica CIX, Universidad Autónoma, Cantoblanco, 28049 Madrid, Spain,
Ángeles I. Díaz, Depto. Física Teórica CIX, Universidad Autónoma, Cantoblanco, 28049 Madrid, Spain,
Jordi Cepa, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain,
Hector Castañeda, Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain
We present narrow-band Hα imaging and long-slit optical and near infrared spectroscopy of the giant HII region NGC 2363. We have found broad emission lines at 4686 Å and at 5810 Å attributed to WC stars at 6 arcsec to the East of the brightest core of the region. We confirm the existence of low-intensity broad components in Hα and [OIII] which extend some 500 pc. We have derived the physical conditions and chemical composition of the gas in 15 different zones in the region, and do not find significant variations in the abundances. The Paschen discontinuity has been found in emission. The Pa electron temperatures obtained are significantly smaller than those obtained from the [OIII] and [SIII] emission lines, indicating the presence of large temperature fluctuations.
One of the targets of the GEFE programme is the giant HII region NGC 2363 located in the SW of the irregular galaxy NGC 2366. This is one of the largest extragalactic HII regions with high surface brightness. The object was observed in La Palma in narrow band Hα and long-slit spectrophotometry from [OII] λ3227 to [SIII] λ9532 at two positions, at the brighest core of the region (which we call knot A) and at 6 arcsec to the East (knot B).
The object was observed with the 1-m JKT telescope. We used a CCD with a spatial scale of 0.3 arcsec pixel−1.
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