bluuebunny/crossref_metadata_2025 huggingface dataset:
A theoretical study of the changes occurring in the ozonosphere during a total eclipse of the sun
Authors: Hunt B. G.
Published: January 2012

A theoretical investigation has been made into the variation of the ozone concentration in the atmosphere which results from an eclipse of the sun. The variation of the ozone concentration with time was followed by numerically integrating the relevant differential equations, allowing for the change in the solar radiation intensity reaching the earth's atmosphere during the eclipse. The results show that an increase of only 0.6 % occurs in the total ozone amount, and that the eclipse does not affect the ozonosphere below 45 km. The theoretical results are compared with experimental observations and reasons are advanced for the discrepancy between the two, which indicate that better agreement should be obtained when corrections for limb darkening of the sun are incorporated in the analysis of the experimental results.
Hemispheric water balance for the IGY
Authors: Starr Victor P. , Peixoto Jose P. , Crisi Alfred R.
Published: January 2012

A study of the hemispheric water balance over the northern hemisphere during the IGY covering the mean conditions for the calendar year 1958 is presented. The study includes analyses of the amount of precipitable water, of the vertically integrated water vapor transport vector field and of the divergence of water vapor transport for the hemisphere. Some implications of the water vapor divergence field are deduced which are important for hydrology and oceanography. Finally, the water vapor balance is discussed in the light of various meteorological considerations.
Energy distribution near jet stream, and associated wave-amplitude relations
Authors: Newton Chester W. , Omoto Yukio
Published: January 2012

In a progressive wave system, the meander of the jet-stream axis typically exceeds the amplitude of the streamlines. This feature is shown to be required by both kinematic and energetic considerations. The specific energy (sum of stream function and kinetic energy) varies along the jet-stream axis, being greatest at the troughs and smallest at the ridges, in proportion to the celerity and amplitude of the wave pattern. In a synoptic example, it is demonstrated that the jet-stream axis is essentially advected by the wind in an isentropic surface, with satisfaction of energy requirements. Schematic illustrations are given, of some relationships between the jet-stream axis and the contour field.
Further studies of the properties of cellular convection in a conditionally unstable atmosphere
Authors: Kuo H. L,
Published: January 2012

The problem of convection in an atmosphere which is stable for dry adiabatic descending motion but unstable for saturated ascending motion is analyzed, with a view to the determinations of the preferred areas of the ascending and descending regions and the distributions of the convection currents. Two somewhat different approaches have been formulated, one is based on an integral relation obtained from the governing linearized differential equation while the other is based on the energy integral. It is found that the area of the ascending region tends to decrease while that of the descending region tends to increase with increasing static stability for unsaturated motion, but both of them are finite under all realistic conditions. On the other hand, when the mean lapse-rate is far above the moist-adiabatic lapse-rate, the consideration of the maximum efficiency in the production of available potential energy gives a much larger preferred area ratio, which tends to approach a constant value for every given static stability factor in the descending region.The theory predicts that for large stability factor R′2 (> 100) in the descending region the area ratio Aa/Ad increases linearly with the ratio R1/R′2 of the stability factors whereas for smaller R′2 (< 100) Aa/Ad increases more slowly.The predicted area ratio of the ascending and descending regions may vary from 1/2 to 1/30 from nearly neutral to normal conditions in the atmosphere, which agree quite closely with that obtained from satellite observations when reasonable values of eddy viscosity and eddy conductivity are assumed. Alternatively, we may also make use of this theory and the observed area ratio to determine the appropriate eddy viscosity coefficient, if the static stability factor in either the ascending or the descending region is known. The nonlinear heat transfer has also been analyzed.
Methods of measuring solar and terrestrial atmospheric circulations
Authors: Macdonald Norman J.
Published: January 2012

In order either to support or to cast doubt upon the mode of study of the circulation of the solar photosphere recently employed by Ward, a comparable use of his methods is made in a test study of the terrestrial atmosphere for which extensive investigations by independent procedures are available. In a qualified over-all manner, Ward's procedures for measuring the large-scale horizontal eddy components from sunspot displacements are given vindication.
Sur la circulation transversale associée à un courant atmosphérique
Authors: Van Mieghem Jacques
Published: January 2012

A criticism of the interpretation of the circulation theorem is followed by an
investigation of the different factors which contribute to a transversal circulation in
a horizontal current.
Duration of Lightning Strokes and Occurrence of Multiple Strokes
Authors: Norinder Harald
Published: January 2012

It is shown that the total duration of lightning strokes, the occurrence of
multiple strokes and the time interval between them are partially influenced when
measurements are made on direct strokes to tall objects. By recording the radiated
electromagnetic field of lightning discharges in antenna circuits with cathode ray
oscillographs at great distances from the lightning paths it was possible to obtain
extensive data on the variation characteristics of lightning. Special methods were
developed in order to analyse the lightning discharges with regard to the sequence of
multiple strokes and the slow moving after-variation. A comparison of the discharge
characteristics of lightning in Sweden with corresponding results from lower latitudes
leads to the assumption that the intensity of thunderstorms is greater in low latitudes
than in high latitudes. This involves researches of a geophysical problem of greatest
interest from different points of view.
The Circulation of the High Troposphere over China in the Winter of 1945–46
Authors: Yeh Tu-Cheng
Published: January 2012

The paper studies the structure of the high troposphere over China in the autumn
of 1945 and winter of 1945–46. The principal feature is the existence of two belts of
maximum westerlies, one flowing around the southern and the other around the northern
edge of the Tibetan Plateau. The southern jet stream (the main one) is extremely
stationary in position. Its speed increases downstream beyond the edge of the Asiatic
continent. The onset of this southern jet stream is abrupt in the middle of October over
central and southwestern China and advances downstream at a speed of about 3° longitude
per day.
South of this main jet stream is a belt of extremely uniform absolute
vorticity which is zero in December and January. In spite of the existence of zero
absolute vorticity the circulation above 15,000 feet is strikingly stable. Below 10,000
feet is the regular procession of warm troughs and cold ridges.
Comparison with the
conditions along 76° E and the east coast of United States has also been made. The
difference in the structure of the basic current along the east coasts of the two
continents suggests an explanation of the observed formation of winter typhoons off the
Chinese coasts versus the non-existence of such storms in the Caribbean Sea in the cold
season.
The Effect of Atlantic Blocking Action upon European Climate
Authors: Rex Daniel F.
Published: January 2012

The results of the individual analysis of six cases of Atlantic blocking action are presented in the form of mean surface and upper-level pressure distributions and of mean regional precipitation and surface-temperature isanomal patterns for winter and for summer blocked periods over the European area. A “mean” blocked sea-level pressure distribution, together with its associated isanomal pattern, are compared with similar charts constructed for a case of strong European zonal flow. A summary of the weather regime associated with European blocking is given, and variable blocking activity is discussed as a factor in the recent climatic change which has been observed over the North Atlantic-European area.
Eddy Flux of Heat and Momentum during Two Years at Stockholm-Bromma
Authors: Nyberg A. , Schmacke E.
Published: January 2012

The eddy flux of momentum, sensible heat and latent heat has been computed from measured temperature, humidity and wind data from the aerological station Bromma 59° 21ʹ  N, 17° 57ʹ  E. The results obtained have been compared with similar computations for Larkhill 51° 11ʹ  N, 01° 48ʹ  W made by Priestley. A comparison has also been made with values obtained by using geostrophic winds kaken from synoptic charts. An estimation of the heat and momentum gained by eddy flux in the zone between 51° N and 59° N and north of 60° N has been made.
Meridional Flux of Angular Momentum in the Tropics
Authors: Starr V. P. , White R. M.
Published: January 2012

The results of an attempt to measure the meridional flux of angular momentum across the vicinity of 13° N latitude from actual wind data are presented. It is found that the average flux for one year is directed northward but is much smaller than the corresponding flux at 31° N as obtained from a similar hemispheric study made earlier for that latitude. According to the data the flux at 13° is due mainly to horizontal exchange processes which are most vigorous at an elevation of about 35,000 feet.
Composition of Atmospheric Precipitation: I. Nitrogen compounds
Authors: Eriksson Erik
Published: January 2012

The purpose of this paper is to present a survey of published data on chemical analysis of atmospheric precipitation; to discuss different cycles proposed for inorganic compounds in atmospheric precipitation and, finally, to assess the importance of these compounds from different points of view. Investigations of rainwater with a view to determine atmospheric pollution in industrial areas will be mentioned incidentally but no results will be given in detail as they concern only small areas and abnormal conditions. The literature on this special subject is, furthermore, rather voluminous and should well deserve a separate review.
A Laboratory Study of the Wind-driven Ocean Circulation
Authors: Von Arx William S.
Published: January 2012

Experiments with rotating oceanographic models are being attempted in the laboratory at Woods Hole in the hope that some information may be gained which will help to close the gap between recent theories of ocean circulation and the observed nature of the circulation. Recent theoretical descriptions by STOMMEL (1948) and MUNK (1950) indicate the broad features of the climatological mean circulation pattern. In contrast, observations usually allow description of possibly transient situations in only relatively small regions. The major observational problem at the moment, short of synoptic measurements over large areas, is to learn how the observations made from moving ships fit into the pattern of very large scale fluid processes. Some insight has already been gained through the search for atmospheric counterparts initiated by Dr C.-G. Rossby, and it is hoped that a wind-driven model of the oceans may offer additional clues. It is recognized that ocean models cannot be scaled in every particular and that the scales taken into account may lead to error since processes of verification, ordinarily used to test the suitability of hydraulic models, cannot be applied. Thus the behavior of a rotating model can bear a limited resemblance only to contemporary ideas of what the primary ocean circulation may be like. In terms of these ideas, however, it has been possible to reproduce westward intensification of the primary circulations in compartments shaped like the North Atlantic and North Pacific basins. Sargasso Sea-like features and several details have also appeared which are qualitatively like contemporary views of the major motions of the sea. These major, and some minor features of the circulation develop rapidly under wind-stress applied to homogeneous water.
The Tyndall Effect of Uniform Minerogenic Suspensions
Authors: Jerlov N. G. , Kullenberg B.
Published: January 2012

The distribution of matter suspended in ocean water was studied during the Swedish Deep-sea Expedition be measuring the Tyndall effect in water samples (JERLOV, 1953). The scattering, s km–1, caused by particles in suspension was computed.
A Study of T Phases Recorded at the Kiruna Seismograph Station
Authors: Båth Markus
Published: January 2012

Five cases of clear T phases from earthquakes in the Norwegian Sea recorded at Kiruna since 1951 are studied. To the author's knowledge these observations are the first of this kind in Europe and also the first so far to the north – on the borders of the Arctic Ocean. It is verified that T propagates as a sound wave through the water. Different phases, constituting T, have been identified, travelling along the land path as Pg, Sg, and a third wave with a land velocity of 2.7 km/sec, probably an S wave in more superficial layers than granite. The conditions for sound-channel transmission in the ocean are studied. The efficient use which can be made of the T phase in epicentre locations is illustrated with a particular case. The period of T is remarkably constant and equal to 0.5 sec. By amplitude calculations it is shown among other things that different submarine earthquakes are not equally efficient in producing a T phase; reasons for this behaviour are discussed. A theoretical explanation is given for the fact that at the same time as the amplitude of T may be larger than that of P at Kiruna, there is no T, but a clear P recorded at Uppsala.
The Present Climatic Fluctuation and its Bearing on a Reconstruction of Pleistocene Climatic Conditions
Authors: Mather John R.
Published: January 2012

Study of the broad scale pressure, temperature, and precipitation changes which have occurred over the Northern Hemisphere during the last forty years gives considerable information concerning the nature and mechanism of a climatic change. If it is assumed that these small-scale changes resemble in certain aspects those that have occurred in the great glacial to interglacial changes of the Pleistocene period, conclusions concerning the broad scale meteorologic conditions of that period can be drawn. Evidence from synoptic meteorology is also used to reveal possible circulation changes accompanying the shift from a glacial to an interglacial period. Certain ideas obtained from these studies are further investigated by means of more detailed studies over North America.
Chemical Denudation in Sweden
Authors: Arrhenius O.
Published: January 2012

Many analyses of groundwater have been made by the Swedish Health authorities. Of those about 10,000 have been used for an attempt to map the geographic distribution of various substances. The factors analyzed are: Total amount of inorganic substances, Ca, Fe, Mn, NH4, SO4, Cl, NO3, HCO3, PO4, pH and oxidation by permanganate. It is found that the water of wells with a depth less than 2 m are more diluted than that of the deeper ones. Scania and the plains of the later district have rich waters whereas the Highlands of Southern Sweden and the northern part of the country (Norrland) have water with a low salt content. Drilled wells are richer than the shallow ground water wells. The chemical denudation is much stronger than formerly calculated. One can estimate that the topmost metre of the soil has lost about 1/5 of its weight by denudation since the ice age. Great losses are also caused through the sewage waters which are carried away to the sea, by the burning of straw etc. Very much may be done in order to stop or to counteract the chemical denudation. A well planned crop rotation, planning of a forest culture which improves the soil conditions, taking care of all affalls are some of the roads leading to a decreased chemical denudation of the soil.
On the Chemical Climate and its Variation with the Atmospheric Circulation Pattern
Authors: Rossby C.-G. , Egnér H.
Published: January 2012

A study of the chemical composition of monthly precipitation samples from a number of stations in Sweden brings out the existence of significant variations in the relative proportions of chlorides and sodium depending upon the general character of the prevailing circulation. In maritime westerly flows the weight ratio of chloride to sodium decreases eastward to values which lie far below the value characteristic of sea water. In precipitation falling from arctic or polar continental air masses the chloride component is almost completely absent. The highest amounts of chlorides relative to sodium are observed in precipitation from warm and most air masses reaching Sweden from the south or southeast.

Significant variations are observed also in the yearly means of the sodium and sulphur deposits depending upon the dominance of maritime or continental air currents.

A sketch map of the “average” chloride concentration in European precipitation prepared from miscellaneous older data lends support to the results of the analysis of the monthly data. The separation of the chemical components indicated by this study would seem to be of considerable geochemical interest since it would permit different maritime salts to be deposited in widely separated parts of the continents. It is not inconceivable that a detailed study of the association between different circulation patterns and the corresponding chemical climates might permit us to draw inferences concerning variations in the atmospheric circulation during post-glacial times, e.g. from the data on the chemical stratification in raised bogs now becoming available through the investigations by Mattson and Koutler-Andersson.
Distribution of Radioactivity in Pelagic Clays
Authors: Arrhenius Gustaf , Goldberg Edward D.
Published: January 2012

An attempt is made to study the localization of radioelements in different mineral phases of pelagic clay sediments. The results so far obtained indicate that the ionium supported radium is redistributed by diffusion through the interstitial solution and that the authigenic zeolite phillipsite plays an important role as a scavenger of radioelements within the deposit. The mechanism of transfer of radioelements from the ocean to pelagic deposits is discussed, and points of uncertainty in the interpretation of the distribution of gross beta-activity are indicated.
A Two-parameter Representation of the Normal Temperature Distribution of the 1,000—500 mb Layer
Authors: Arnason G. , Vuorela L.
Published: January 2012

Height normals for 1,000, 700 and 500 mb, published by U.S. Weather Bureau, have been used to study the normal temperature field of the 1,000—500 mb layer by means of a simple model. In this model the normal temperature-height curve is replaced by one having a temperature lapse-rate independent of height in such a way that the thicknesses of the sub-layers 1,000—700 and 700—500 mb are correctly represented by the model. As a consequence, the temperature as well as its horizontal gradient and the thermal wind all have a linear variation with height and may be described in terms of two parameters, the temperature lapse-rate k and a “representative” 1,000 mb temperature τ0. Hemispheric maps for these parameters as well as the thermal wind at 1,000 and 500 mb have been prepared for the months January and July. The major frontal zones of the atmosphere appear clearly on the τ0-maps in positions which agree essentially with those shown earlier by a number of meteorologists. The July map reveals, however, a strong baroclinic zone in high latitudes, surrounding the polar cap, not shown clearly in earlier presentations of the low-level baroclinity. The k-charts disclose large horizontal variation in the temperature lapse-rate, and the charts for the thermal wind show that its variation with height is very pronounced in middle and high latitudes.
Salt Nuclei, Wind and Daily Rainfall in Hawaii
Authors: Woodcock A. H. , Mordy W. A.
Published: January 2012

The discovery of large sea-salt particles at cloud levels led to the hypothesis that these particles act as nuclei on which raindrops initially form within clouds and to the suggestion that the amount of rainfall on an oceanic island might be a function of the number of the salt particles in the air. Exploratory observations of rain and airborne salt in Hawaii, which were intended to test this suggestion, are presented and discussed. These observations do not prove that greater numbers of salt nuclei are related to greater amounts of rain. They do, however, indicate that such a relationship may exist, and that additional field studies should be made which utilize the pertinent results of the present study.
Tests of the Salt-Nuclei Hypothesis of Rain Formation
Authors: Woodcock A. H. , Blanchard D. C.
Published: January 2012

Atmospheric chlorides in sea-salt nuclei and the chlorides dissolved in shower rainwaters were recently measured in Hawaii. A comparison of these measurements reveals the remarkable fact that the weight of chloride present in a certain number of nuclei in a cubic meter of clear air tends to be equal to the weight of chloride dissolved in an equal number of raindrops in a cubic meter of rainy air. This result is explained as an indication that the raindrops grow on the salt nuclei in some manner which prevents a marked change in the distribution of these nuclei during the drop-growth process.

The data presented add new evidence in further support of the salt-nuclei raindrop hypothesis previously proposed by the first author (WOODCOCK, 1952).
Accelerated Dust Grains and the Highest Cosmic Ray Energies
Authors: Herlofson N.
Published: January 2012

The events following the impact of a fast ionised grain with the atmosphere are examined, and some similarity is found between the expected air shower and observations of the largest cosmic ray showers. It is concluded that the largest air showers are in any case initiated by primaries accelerated outside the solar system, whether the primaries are dust grains or single nuclei.
Experimental Investigation of the Inhibition of Convection by a Magnetic Field
Authors: Jirlow K.
Published: January 2012

The theory of stability of a layer of fluid heated below has been developed by RAYLEIGH (1916), JEFFREYS (1926, 1928) and PELLEW and SOUTHWELL (1940).
Mineral Composition of Rainwater
Authors: Larson T. E. , Hettick Irene
Published: January 2012

Analyses of 62 rainwater samples collected at the University of Illinois Airport near Savoy, Ill., showed that on the basis of equivalent concentrations, the chloride is equal to the sum of sodium and potassium. Sodium was three times the potassium. Calcium plus magnesium was 10 times the chloride and equal to the sum of the bicarbonate and sulfate. The sulfate was equal to twice the sum of ammonium and nitrate.

These results indicate salt from sea mist to constitute a negligible proportion of the mineral content. They also indicate the presence of air pollution by the combustion of fuel.
Trade Cumulus Cloud Groups: Some Observations Suggesting a Mechanism of Their Origin
Authors: Malkus Joanne Starr
Published: January 2012

On a recent field trip to the western Caribbean, temperature gradients in the surface layers of the trade-wind oceans were found and related to the presence of cumulus cloud groups. The cloud groups generally formed over and slightly downwind of warm spots which were several kilometers in extent along the wind and 0.1—0.3° C in amplitude. Clouds were not found in the absence of warm spots although warm spots were occasionally encountered without clouds.

Air circulations, similar to but weaker than those produced by heated land masses, are hypothesized to exist over oceanic warm spots and their magnitude is estimated from previous work on heated islands. Observed differences in low-level moisture structure between clear and cloudy areas may be interpreted in terms of such circulations and their evolution with time. Some suggestions are made concerning the life cycles of trade cumuli.
The Natural Distribution of Radiocarbon and the Exchange Time of Carbon Dioxide Between Atmosphere and Sea
Authors: Craig Harmon
Published: January 2012

Steady-state equations governing the transfer and distribution of a radioactive isotope between its various exchange reservoirs are applied to the natural distribution of carbon 14. The radiocarbon enrichment or depletion in each reservoir, relative to the hypothetical state in which mixing is infinitely faster than the decay rate, is evaluated as a quantitative function of the exchange rates between the reservoirs. From the observed distribution of C12, C13, and C14 in the atmosphere, biosphere, and sea, and from the estimated production rate of C14 by cosmic rays, the residence time of a carbon dioxide molecule in the atmosphere, before entering the sea, is found to be between four and ten years.

The atmospheric residence time may also be evaluated, independently of the estimated C14 production rate, by considering the functional dependence of the C14 concentration in the oceanic mixed layer on the residence times in the atmosphere and the deep sea. This second method of evaluation also leads to an atmospheric residence time of about seven years. The average annual exchange flux of carbon dioxide into the sea is thus about 2 × 10−2 moles per square centimeter of sea surface. The average residence time of carbon dioxide in the deep sea is estimated as probably not more than about 500 years.
A Transparency-Meter for Ocean Water
Authors: Jerlov N. G.
Published: January 2012

The significance of the geometry of the optical system in extinction measurements for a liquid dispersion is emphasized. In particular, the mechanism by which light is lost by scattering in a transparency-meter in the sea is discussed. The strongly selective absorption of yellow substance is demonstrated. A new transparency-meter sufficiently accurate for measurements in clear ocean water is described. A long optical path in the meter is attained by multiple reflection between three concave mirrors of equal curvature. The depth is recorded by means of a new device.
Preliminary Research in Objective Analysis
Authors: Johnson D. H.
Published: January 2012

Simple mathematical surfaces are used to interpolate numerically within two-dimensional networks of 500 mb contour heights and winds. The effect on the errors of interpolation of varying (i) the relative weights given to the measured contour heights and winds, (ii) the complexity of the mathematical surface, and (iii) the layout and dimensions of the network is examined. It is concluded that in areas where observations are reasonably dense, numerical analysis will be at least as satisfactory as the currently used subjective graphical method.
Determination of Deuterium-Hydrogen Ratios in Hawaiian Waters
Authors: Friedman I. , Woodcock A. H.
Published: January 2012

Previous determinations of the deuterium-hydrogen ratios in natural waters revealed the fractionation of deuterium; a fractionation resulting from differences in the vapor pressure of H2O and HDO. Measurements of the deuterium in sea, rain, and condensate waters of Hawaii, are reported here. These results show a concentration of deuterium in sea-surface waters, and an inverse relationship of D with altitude in rain and condensate taken on a mountain side. The possible significance of these measurements for cloud physics studies is briefly discussed.
Factors Associated with Serum Hepatitis B Surface Antigen Levels and Its On-Treatment Changes in Patients under Lamivudine Therapy
Authors: Chen Jinjun , Wang Zhanhui , Zhou Bin , Wang Yanjun , Hou Jinlin
Published: January 2012

Background

We aimed to investigate factors associated with serum hepatitis B surface antigen (HBsAg) levels and its kinetics under lamivudine treatment in chronic hepatitis B patients.

Methods

HBsAg levels were measured with the Architect HBsAg assay (Abbott laboratories, Abbott Park, IL, USA) in genotype B (HBV/B) or C (HBV/C) patients ( n=218). Early HBsAg kinetics in 86 hepatitis B e antigen (HBeAg)- positive patients and long-term HBsAg changes in 45 patients with rapid and sustained viral suppression were further analysed.

Results

Mean HBsAg levels were higher in male ( n=181) than in female ( n=37) patients (3.59 versus 3.23 log10 IU/ ml; P=0.036), and higher in 121 HBV/B than in 97 HBV/C patients (3.68 versus 3.34 log10 IU/ml; P=0.006). In addition to HBV DNA loads ( P<0.001), male gender ( P=0.012) and HBV/B infection ( P=0.035) were independently associated with higher HBsAg levels in antiviral-naive patients. HBsAg increases (0.00–0.87 log10) were found in 28/86 patients who obtained viral suppression under 12 weeks of lamivudine therapy. Higher baseline HBsAg levels ( P=0.046), HBV/B infection ( P=0.007) and faster HBV DNA declines ( P=0.006) independently contributed to greater HBsAg decreases under 12 weeks treatment. An apparent dissociation between HBsAg and HBV DNA changes were found in 14/45 patients with rapid and sustained viral suppression, who had low baseline HBsAg levels and predominant HBV/C infection.

Conclusions

HBV/B and male gender were associated with higher HBsAg levels in antiviral-naive patients. Higher baseline HBsAg levels and HBV/B infection contributed to greater early HBsAg declines in HBeAg-positive patients, and might correlate with discordance between HBsAg and HBeAg or HBV DNA under long-term lamivudine treatment.
Los métodos pedagógicos de la Corona para disciplinar la experiencia de los navegantes en el siglo XVI
Authors: Sánchez Martínez Antonio
Published: January 2012

Dada la escasa formación científica de los pilotos que viajaban a Indias en los primeros años del siglo XVI, la Corona española, primero con Carlos I al frente y más tarde con Felipe II, no sólo se conformó con crear instituciones y cargos científicos para organizar el saber náutico y cosmográfico del Nuevo Mundo, sino que además diseñó métodos pedagógicos, en forma de cátedras, cursos y exámenes, para la formación y licencia de aquellos navegantes dispuestos a surcar el “Mar Océano”. El objetivo último de la Monarquía era, por un lado, garantizar el mantenimiento de su productivo imperio de ultramar y, por el otro, velar tanto por la seguridad de sus flotas y hombres como por las arcas del Estado, pues los naufragios de los navíos suponían grandes pérdidas económicas. La unión entre ciencia y experiencia sería el mejor remedio.
Hacia una Historia Atlántica: visiones religiosas compartidas
Authors: Contreras Jaime , Martínez de Codes Rosa María
Published: January 2012

La historiografía de la cultura religiosa de los espacios atlánticos ha prestado escasa atención a los substratos comunes que la conformaron en el Nuevo Mundo. Lejos de reiterar los numerosos elementos que han diferenciado las formas culturales de colonización entre el espacio anglosajón y los espacios hispanos, se insiste en este estudio en el hecho de que fueron muchas las complementaciones entre ambos escenarios y que, en consecuencia, es preciso incidir más en esta línea de investigación. Ello ha de contribuir a asentar los elementos de una Historia Atlántica más integrada.
Presión e intereses en torno al cargo de protector general de indios del Nuevo Reino de León: el caso de Nicolás de Villalobos, 1714-1734
Authors: Baeza Martín Ascensión
Published: January 2012

La perniciosa transformación sufrida por el sistema de utilización de la mano de obra indígena en el Nuevo Reino de León, caracterizado por los estragos y esclavitud a los indios en las encomiendas o congregas, provocaban su rebeldía. Los frecuentes asaltos a los colonos españoles y sus propiedades, así como las expediciones y castigos de estos contra los aborígenes reflejaban las duras condiciones de vida en esa provincia del nordeste del Virreinato de Nueva España y el constante estado de guerra de la misma. Con los substanciales cambios implantados desde el gobierno virreinal mediante el envío en 1714 del comisionado Francisco de Barbadillo Victoria y la creación por éste del cargo de protector general de indios en esa tierra, se trató de frenar esta incontrolable situación. La dificultad de que se afianzara la figura del protector, tan necesaria en los primeros tiempos de las reformas, dejaría ver los partidismos, pasiones e intereses de las autoridades y de los diversos sectores sociales de esa región fronteriza.
Marine benthic cartography of the Cap de Creus (NE Catalan Coast, Mediterranean Sea)
Authors: Sardá Rafael , Rossi Sergi , Martí Xavier , Gili Josep Maria
Published: January 2012

The marine benthic cartography of the Cap de Creus and surrounding areas (NW Mediterranean Sea) was obtained by combining classical grabbing methods with more recent imaging methods based on a remotely operated vehicle. The goals of this particular survey can be summarized as follows: 1) to chart the benthic communities (and the area of each one); 2) to evaluate the benthic diversity of the areas; 3) to produce visual documentation of the distributions of the benthic organisms; 4) to identify human-induced pressures on the benthic environment; 5) to make recommendations for future management based on the visual assessment; and 6) to set up a new methodology for making large biocenosis maps that would help to manage marine protected and non-protected areas. The marine environment off the Alt Empordà County was shown to have a very rich diversity of benthic habitats. Twenty community categories were identified from videos and grabs. Though benthic habitats mostly located inside a marine protected area were assessed, man-made objects were seen in 10% of the analyzed minutes filmed. The study led to a comprehensive review of the main biotope systems of this coastal area, as well as their environmental condition, and this will be an essential element for their future management.
Revision and redescription of the species previously included in the genus Amphilaphis Studer and Wright in Studer, 1887 (Octocorallia: Primnoidae)
Authors: Zapata-Guardiola Rebeca , López-González Pablo J.
Published: January 2012

The taxonomy of the primnoid genus Amphilaphis Studer and Wright in Studer, 1887 has been in a confused state for a long time and a revision of the species included in that genus has become a necessity. We have revised and redescribed the species previously included in the genus using up-to-date technology, such as polyp and sclerite images obtained with scanning electron microscopy (SEM). As a result of this study, because the type species of Amphilaphis is actually a Thouarella species, we consider the genus Amphilaphis to be no longer valid. One of the species previously considered in Amphilaphis has a set of morphological characters that are not recognizable in any of the current primnoid genera. Primnocapsa n. gen. has a dichotomous branching pattern, polyps placed singly, in spirals around the branchlets, 8 opercular scales with the inner surface keeled and with 2 mounds basally and 8 marginal scales offset from the operculars. The new genus is described and illustrated. Moreover, one of the re-examined species has been included in a new subgenus, Faxiella n. subgen. of Plumarella Gray, 1870 because it has polyps placed in pairs. Finally, the remaining re-examined species have been included in the genus Thouarella Gray, 1870, one of the most specious primnoid genera.
Seasonal, lunar and tidal control of ichthyoplankton dynamics at the interface between a temperate estuary and adjacent coastal waters (western Portugal)
Authors: Lígia Primo Ana , Miranda Azeiteiro Ulisses , Cotrim Marques Sónia , Ré Pedro , Ângelo Pardal Miguel
Published: January 2012

Influence of season, lunar-tide cycle and tide on ichthyoplankton at the interface between Mondego estuary and the adjacent coast and on up-estuary transport was evaluated. Seasonal samples were collected at a fixed station at the mouth of the estuary during diel cycles, at neap and spring tides. Additionally, four sampling stations along the estuary were assessed. Pomatoschistus spp. was the main estuarine taxon, while Sardina pilchardus and Parablennius pilicornis were the most important marine species. Ichthyoplankton entrance and transport along the estuary presented a seasonal pattern with higher densities during summer. Lunar-tide cycle also represented an important influence, structuring communities that reach the estuary and their subsequent distribution. Solea senegalensis and Sardina pilchardus seemed to take advantage of spring tides to enter the estuary. S. pilchardus appear to be using tides to move upstream of the estuary. Ichthyoplankton entrance in the estuary seemed related to species spawning period, while its distribution within the estuary depends on in situ spawning and on the capacity of species to counteract currents and river flow. The present study provides a better understanding of ichthyoplankton dynamics at the interface of two coastal systems, reinforcing knowledge of the lunar-tide cycle influence on ichthyoplankton communities.
Identification of Lessepsian fish species using the sagittal otolith
Authors: Tuset Víctor Manuel , Azzurro Ernesto , Lombarte Antoni
Published: January 2012

Lessepsian species are marine organisms that enter the Mediterranean through the Suez Canal, a phenomenon that has dramatically increased in recent decades. The present study describes the morphological characteristics of the sagittal otoliths of 22 Lessepsian fish species collected at four locations in the Mediterranean Sea. These structures are commonly used in the identification of species found in the digestive tracts of predators, and their morphological description is mainly needed as a tool for trophic studies. Here we used the Automated Taxon Identification (ATI) system of the AFORO web database to determine the accuracy of classifying Lessepsian fish otoliths compared with otoliths of native Mediterranean species. The otolith contour analysis correctly classified 92.5% of the specimens, showing that these species have otoliths that can be clearly distinguished from native ones. Four different groups of otoliths were identified according to the morphological differences between the otoliths and the ATI analysis results: a) unusual shapes with no similarities to native species; b) unusual shapes with similarities to phylogenetically distant native species; c) common shapes with similarities to phylogenetically close native species; and d) common shapes with morphological characters related to other native congeners, although they are not classified with them.
Cutting Edge: A Variant of the IL-23R Gene Associated with Inflammatory Bowel Disease Induces Loss of MicroRNA Regulation and Enhanced Protein Production
Authors: Zwiers Antonie , Kraal Laurens , van de Pouw Kraan Tineke C. T. M. , Wurdinger Thomas , Bouma Gerd , Kraal Georg
Published: January 2012

IL-23R gene variants have been identified as risk factors for two major inflammatory bowel diseases (IBDs), Crohn’s disease and ulcerative colitis, but how they contribute to disease is poorly understood. In this study, we show that the rs10889677 variant in the 3′-untranslated region of the IL-23R gene displays enhanced levels of both mRNA and protein production of IL-23R. This can be attributed to a loss of binding capacity for the microRNAs (miRNAs) Let-7e and Let-7f by the variant allele. Indeed, inhibition and overexpression of these miRNAs influenced the expression of the wild type but not the variant allele. Our data clearly demonstrate a role for miRNA-mediated dysregulation of IL-23R signaling, correlated with a single nucleotide polymorphism in the IL-23R strongly associated with IBD susceptibility. This implies that this mutation, in combination with other genetic risk factors, can lead to disease through sustained IL-23R signaling, contributing to the chronicity of IBD.
Trypanosoma cruzi Immune Evasion Mediated by Host Cell-Derived Microvesicles
Authors: Cestari Igor , Ansa-Addo Ephraim , Deolindo Poliana , Inal Jameel M. , Ramirez Marcel I.
Published: January 2012

The innate immune system is the first mechanism of vertebrate defense against pathogen infection. In this study, we present evidence for a novel immune evasion mechanism of Trypanosoma cruzi, mediated by host cell plasma membrane-derived vesicles. We found that T. cruzi metacyclic trypomastigotes induced microvesicle release from blood cells early in infection. Upon their release, microvesicles formed a complex on the T. cruzi surface with the complement C3 convertase, leading to its stabilization and inhibition, and ultimately resulting in increased parasite survival. Furthermore, we found that TGF-β–bearing microvesicles released from monocytes and lymphocytes promoted rapid cell invasion by T. cruzi, which also contributed to parasites escaping the complement attack. In addition, in vivo infection with T. cruzi showed a rapid increase of microvesicle levels in mouse plasma, and infection with exogenous microvesicles resulted in increased T. cruzi parasitemia. Altogether, these data support a role for microvesicles contributing to T. cruzi evasion of innate immunity.
A Proposed Algorithm Predictive for Cytotoxic T Cell Alloreactivity
Authors: Jöris Monique M. , van Rood Jon J. , Roelen Dave L. , Oudshoorn Machteld , Claas Frans H. J.
Published: January 2012

Previously, we showed that with an increasing number of amino acid differences in single HLA class I-mismatched molecules, the probability of T cell alloreactivity decreases. It is unlikely that every amino acid difference will affect T cell alloreactivity in a similar way; we hypothesized that the effect of an amino acid difference may be dependent on its position and/or physicochemical properties. We selected 131 patient/donor pairs with either a single HLA-A or -C mismatch in the graft-versus-host direction and that were compatible for HLA-B, -DRB1, and -DQB1. The alloreactive CTL precursor (CTLp) frequency was determined and associated with the amino acid differences between the single HLA class I mismatches. In the β sheet, only amino acids that are noncompatible in their physicochemical properties affect T cell alloreactivity, whereas in the α helices, both compatible and noncompatible amino acids affect CTLp outcome. Positions 62, 63, 73, 76, 77, 80, 99, 116, 138, 144, 147, and 163 were bivariately associated with CTLp outcome, irrespective of the total number of amino acid differences. In multivariate analysis, positions 62, 63, 73, 80, 116, 138, 144, and 163 were found to be most predictive for negative CTLp outcome. These results formed the basis for a weighted predictive mismatch score; pairs with the highest mismatch scores are estimated to be 13 times more likely to have a negative CTLp. This new algorithm may be a tool in donor selection for hematopoietic stem cell transplantation.
CD64 Expression Distinguishes Monocyte-Derived and Conventional Dendritic Cells and Reveals Their Distinct Role during Intramuscular Immunization
Authors: Langlet Christelle , Tamoutounour Samira , Henri Sandrine , Luche Hervé , Ardouin Laurence , Grégoire Claude , Malissen Bernard , Guilliams Martin
Published: January 2012

Although most vaccines are administered i.m., little is known about the dendritic cells (DCs) that are present within skeletal muscles. In this article, we show that expression of CD64, the high-affinity IgG receptor FcγRI, distinguishes conventional DCs from monocyte-derived DCs (Mo-DCs). By using such a discriminatory marker, we defined the distinct DC subsets that reside in skeletal muscles and identified their migratory counterparts in draining lymph nodes (LNs). We further used this capability to analyze the functional specialization that exists among muscle DCs. After i.m. administration of Ag adsorbed to alum, we showed that alum-injected muscles contained large numbers of conventional DCs that belong to the CD8α+- and CD11b+-type DCs. Both conventional DC types were capable of capturing Ag and of migrating to draining LNs, where they efficiently activated naive T cells. In alum-injected muscles, Mo-DCs were as numerous as conventional DCs, but only a small fraction migrated to draining LNs. Therefore, alum by itself poorly induces Mo-DCs to migrate to draining LNs. We showed that addition of small amounts of LPS to alum enhanced Mo-DC migration. Considering that migratory Mo-DCs had, on a per cell basis, a higher capacity to induce IFN-γ–producing T cells than conventional DCs, the addition of LPS to alum enhanced the overall immunogenicity of Ags presented by muscle-derived DCs. Therefore, a full understanding of the role of adjuvants during i.m. vaccination needs to take into account the heterogeneous migratory and functional behavior of muscle DCs and Mo-DCs revealed in this study.
Cullin 4B Is Recruited to Tristetraprolin-Containing Messenger Ribonucleoproteins and Regulates TNF-α mRNA Polysome Loading
Authors: Pfeiffer Jason R. , Brooks Seth A.
Published: January 2012

TNF-α is a central mediator of inflammation and critical for host response to infection and injury. TNF-α biosynthesis is controlled by transcriptional and posttranscriptional mechanisms allowing for rapid, transient production. Tristetraprolin (TTP) is an AU-rich element binding protein that regulates the stability of the TNF-α mRNA. Using a screen to identify TTP-interacting proteins, we identified Cullin 4B (Cul4B), a scaffolding component of the Cullin ring finger ligase family of ubiquitin E3 ligases. Short hairpin RNA knockdown of Cul4B results in a significant reduction in TNF-α protein and mRNA in LPS-stimulated mouse macrophage RAW264.7 cells as well as a reduction in TTP protein. TNF-α message t1/2 was reduced from 69 to 33 min in LPS-stimulated cells. TNF-3′ untranslated region luciferase assays utilizing wild-type and mutant TTP-AA (S52A, S178A) indicate that TTP function is enhanced in Cul4B short hairpin RNA cells. Importantly, the fold induction of TNF-α mRNA polysome loading in response to LPS stimulation is reduced by Cul4B knockdown. Cul4B is present on the polysomes and colocalizes with TTP to exosomes and processing bodies, which are sites of mRNA decay. We conclude that Cul4B licenses the TTP-containing TNF-α messenger ribonucleoprotein for loading onto polysomes, and reduction of Cul4B expression shunts the messenger ribonucleoproteins into the degradative pathway.
On the restricted divisor function in arithmetic progressions
Authors: Shparlinski Igor E.
Published: January 2012

We obtain several asymptotic estimates for the sums of the restricted divisor function

\tau_{M,N}(k) = \# \{1 \le m \le M, \ 1\le n \le N : mn = k\}

over short arithmetic progressions, which improve some results of J. Truelsen. Such estimates are motivated by the links with the pair correlation problem for fractional parts of the quadratic function

\alpha k^2

,

k=1,2,\dots

with a real

\alpha

.
A Critical Woman
Authors: Oakley Ann
Published: January 2012

Barbara Wootton was one of the extraordinary public figures of the twentieth century. She was an outstanding social scientist, an architect of the welfare state, an iconoclast who challenged conventional wisdoms and the first woman to sit on the Woolsack in the House of Lords.

Ann Oakley has written a fascinating and highly readable account of the life and work of this singular woman, but the book goes much further. It is an engaged account of the making of British social policy at a critical period seen through the lens of the life and work of a pivotal figure. Oakley tells a story about the intersections of the public and the private and about the way her subject’s life unfolded within, was shaped by, and helped to shape a particular social and intellectual context.