Morfología polínica de la familia Primulaceae en Andalucía Occidental

Se estudia la morfología pol inica de nueve especi es de Pri mulaceae en Andalucia Occidental, pertenecientes a los géneros Prímula, Lysimac hia, Asterolinon, Anagallis y Samolus , tanto al microscopi o óptico como electrónico de barrido. Los resultados expuestos ponen de manifiesto e l c aracter euripolínico de esta fami l ia , observandose di f erencias en e l tamaño , número de aperturas y ornamentac iónThe polleo morphology of nine species of Primulaceae from W. Andaluc ía bel onging to the genera Primula, Lysimachia, Asterolinon, Anagallis and Samolus are studied by l ight and scanning electron microscopy . This fami ly is eurypalynous. Sorne diff erences in size, aperture number and ornamentation have been observed

Could CODA methodology be useful in control chart techniques?

On standard control charts, the hypothesis of normality is usually assumed without any additional veri cation. Nevertheless, in some cases this assumption is not accurate and might cause errors in process quality monitoring. In particular, for the control of the proportion of nonconforming units (p-chart) the normality is doubtful when p is small and consequently, lower control limit less than or equal to zero are frequent. Some authors have proposed new techniques to de ne limits in the p-chart. Others have proposed transformations to improve the detection of special causes

Antiferromagnetism in four dimensions: search for non-triviality

We present antiferromagnetism as a mechanism capable of modifying substantially the phase diagram and the critical behaviour of statistical mechanical models. This is particularly relevant in four dimensions, due to the connection between second order transition points and the continuum limit as a quantum field theory. We study three models with an antiferromagnetic interaction: the Ising and the O(4) Models with a second neighbour negative coupling, and the \RP{2} Model. Different conclusions are obtained depending on the model.Comment: 4 pages LateX. Contribution to Lat9

On the interpretation of differences between groups for compositional data

Social polices are designed using information collected in surveys; such as the Catalan TimeUse survey. Accurate comparisons of time use data among population groups are commonlyanalysed using statistical methods. The total daily time expended on different activities by asingle person is equal to 24 hours. Because this type of data are compositional, its sample spacehas particular properties that statistical methods should respect. The critical points required tointerpret differences between groups are provided and described in terms of log-ratio methods.These techniques facilitate the interpretation of the relative differences detected in multivariateand univariate analysis

Synthetic precursor to make alkali activated cements

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Single-photon source over the terahertz regime

We present a proposal for a tunable source of single photons operating in the terahertz (THz) regime. This scheme transforms incident visible photons into quantum THz radiation by driving a single polar quantum emitter with an optical laser, with its permanent dipole enabling dressed THz transitions enhanced by the resonant coupling to a cavity. This mechanism offers optical tunability of properties such as the frequency of the emission or its quantum statistics (ranging from antibunching to entangled multi-photon states) by modifying the intensity and frequency of the drive. We show that the implementation of this proposal is feasible with state-of-the-art photonics technology.Comment: 18 pages, 14 figure

Analysis of fossil planktonic foraminifera: the sieve mesh effect

The choice of the sediment size fraction in the analysis of fossil planktonic foraminifera is of great importance in determining the composition of assemblages. In past studies several size fractions have been utilised. Imbrie and Kipp (1971) stated that “smaller fractions give rise to too many uncertainties in the identification of small specimens and require too long to process. Large mesh size yield undesiderable loss of small species, and small specimens of larger species”. The adoption of coarser sieve meshes has the effect to reduce the percentages of small sized (usually living in cold waters) species (Bé and Hutson, 1977). In a comparison between >63 μm and >150 μm size-fraction of planktonic foraminifera assemblages from NW Atlantic Ocean, Smart (2002), stated that because particular smaller species are either under-represented or even absent from the larger (>150 μm) size-fraction, the smaller (>63 μm) size-fraction must be included in studies of planktonic foraminifera. Di Donato et al. (2008) highlighted in the >150 μm size fraction of a core from the Tyrrhenian Sea, a great loss of the small-sized species Turborotalita quinqueloba in glacial samples, where this species is very abundant. This caused an increase in warm water species such as Globigerinoides ruber, apparently reaching typical Holocene values in some full glacial levels. From the above mentioned statements, it is clear that treatment changes can strongly influence the results of palaeoclimatic reconstructions based on planktonic foraminiferal assemblages. As stated by Aitchison (1986, 1992) scale invariance and subcompositional coherence are fundamental properties of the compositional data analysis (CODA). The main goal of this paper is to verify if the variable relationships pointing out from CODA of foraminiferal assemblages are or not influenced by the size fraction and, more in general, to test the robustness of CODA respect to treatment changes related to different preparation techniques for the analysis of planktonic foraminifera

Aclimatación al frío en diferentes clones de Eucalyptus globulus Labill durante el régimen natural de endurecimiento

En la región mediterránea la principal limitación de la expansión del las plantaciones de Eucalyptus es la ocurrencia periódica de temperaturas bajas durante los meses de invierno (-5 a -10 oC). Por esta razón es crucial implementar un programa para mejorar la resistencia al frío en las especies utilizadas de este género. E. globulus, la especie más extendida en la península ibérica es considerada una especie moderadamente susceptible al frío. Se testaron 16 clones a los cuales se les realizó un seguimiento durante el régimen natural de endurecimiento y la salida del mismo para el periodo 2005-2006. La tolerancia al frío fue evaluada en tejido foliar desarrollado, tanto en hojas pecioladas maduras como en hojas sentadas juveniles, simulando condiciones de helada en ambiente controlado. De esta forma se demostró que existe un proceso de aclimatación de las plantas a las bajas temperaturas a medida que se acumulan las horas de frío y una desaclimatación de las mismas a medida que acaba el invierno. En todos los clones se determinó un máximo de tolerancia para la segunda quincena de enero, lo que corresponde con un total acumulado de 415 horas de frío por debajo de los 7 oC (HF7). Por otra parte se observó un cambio significativo en el umbral de temperaturas que causan un daño al 50% de la superficie del tejido foliar (TL50), siendo el valor medio de éstas -4,5 ºC antes de comenzar la temporada de frío y de – 6,5 ºC una vez alcanzado el máximo de endurecimiento.______________________________The greatest constraint on the expansion of Eucalyptus plantations in the Mediterranean region is the periodic occurrence of low temperatures (–5 to –10 oC) during winter. This has raised the need to launch a programme aimed at increasing the tolerance to cold weather of Eucalyptus species in the region. Eucalyptus globulus, which is the most widespread Eucalyptus species in the Iberian peninsula, is moderately vulnerable to cold. In this work, a total of 16 clones of this species were monitored during their natural hardening regime and at its end over the period 2005–06. Tolerance to cold was evaluated in well-developed tissue of both mature petiolate leaves and seated young leaves by mimicking freezing conditions in a controlled environment. The plants were found to gradually acclimate to low temperatures as the number of cold hours increased and to de-acclimate as the winter neared its end. Tolerance in all clones peaked in the second half of January, after an overall 415 could hours at temperatures below 7 oC (HF7). Also, the temperature threshold below which at least 50% of leaf surface tissue was damaged (TL50) varied markedly, from an average –4.5 oC at the beginning of the cold season to an average –6.5 oC at the point of maximum hardening

Human-vehicle interaction for autonomous vehicles in crosswalk scenarios: Field experiments with pedestrians and passengers

This paper presents the results of real-world testing of human-vehicle interactions with an autonomous vehicle equipped with internal and external Human Machine Interfaces (HMIs) in a crosswalk scenario. The internal and external HMIs were combined with implicit communication techniques using gentle and aggressive braking maneuvers in the crosswalk. Results have been collected in the form of questionnaires and measurable variables such as distance or speed when the pedestrian decides to cross. The questionnaires show that pedestrians feel safer when the external HMI or the gentle braking maneuver is used interchangeably, while the measured variables show that external HMI only helps in combination with the gentle braking maneuver. The questionnaires also show that internal HMI only improves passenger confidence in combination with the aggressive braking maneuver.Comment: 6 pages, 7 figures, 4 tables, conferecence pape