bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid learning of an abstract language-specific category: Polish children's acquisition of the instrumental construction
Authors: DĄBROWSKA EWA , TOMASELLO MICHAEL
Published: June 2008

Rapid acquisition of linguistic categories or constructions is sometimes regarded as evidence of innate knowledge. In this paper, we examine Polish children's early understanding of an idiosyncratic, language-specific construction involving the instrumental case – which could not be due to innate knowledge. Thirty Polish-speaking children aged 2 ; 6 and 3 ; 2 participated in a elicited production experiment with novel verbs that were demonstrated as taking nouns in the instrumental case as patients. Children heard the verbs in sentences with either masculine or feminine nouns (which take different endings in the instrumental case), and were tested with new nouns of the same and of the opposite gender. In both age groups, a substantial majority of children succeeded in generalizing from one gendered form of the instrumental case to the other (especially to the masculine), thus indicating that they have some kind of abstract understanding of the instrumental case in this construction. This relatively early abstract knowledge of an idiosyncratic construction casts doubt on the view that early acquisition requires innate linguistic knowledge.
Rigid thinking about deformables: do children sometimes overgeneralize the shape bias?
Authors: SAMUELSON LARISSA K. , HORST JESSICA S. , SCHUTTE ANNE R. , DOBBERTIN BRANDI N.
Published: June 2008

Young children learning English are biased to attend to the shape of solid rigid objects when learning novel names. This study seeks further understanding of the processes that support this behavior by examining a previous finding that three-year-old children are also biased to generalize novel names for objects made from deformable materials by shape, even after the materials are made salient. In two experiments, we examined the noun generalizations of 72 two-, three- and four-year-old children with rigid and deformable stimuli. Data reveal that three-year-old, but not two- or four-year-old, children generalize names for deformable things by shape, and that this behavior is not due to the syntactic context of the task. We suggest this behavior is an overgeneralization of three-year-old children's knowledge of how rigid things are named and discuss the implications of this finding for a developmental account of the origins of the shape bias.
Early vocabulary development in Danish and other languages: A CDI-based comparison
Authors: BLESES DORTHE , VACH WERNER , SLOTT MALENE , WEHBERG SONJA , THOMSEN PIA , MADSEN THOMAS O. , BASBØLL HANS
Published: June 2008

The main objective of this paper is to describe the trajectory of Danish children's early lexical development relative to other languages, by comparing a Danish study based on the Danish adaptation of The MacArthur-Bates Communicative Development Inventories (CDI) to 17 comparable CDI-studies. The second objective is to address the feasibility of cross-linguistic CDI-comparisons. The main finding is that the developmental trend of Danish children's early lexical development is similar to trends observed in other languages, yet the vocabulary comprehension score in the Danish children is the lowest across studies from age 1 ; 0 onwards. We hypothesize that the delay is related to the nature of Danish sound structure, which presents Danish children with a harder task of segmentation. We conclude that CDI-studies are an important resource for cross-language studies, but reporting of studies needs to be standardized and the availability of published data improved in order to make comparisons more straightforward.
The Early Language in Victoria Study: predicting vocabulary at age one and two years from gesture and object use
Authors: BAVIN E. L. , PRIOR M. , REILLY S. , BRETHERTON L. , WILLIAMS J. , EADIE P. , BARRETT Y. , UKOUMUNNE O. C.
Published: June 2008

The Macarthur-Bates Communicative Development Inventories (CDI) have been used widely to document early communicative development. The paper reports on a large community sample of 1,447 children recruited from low, middle and high socioeconomic (SES) areas across metropolitan Melbourne, Australia. Regression analyses were conducted to determine the extent to which communicative behaviours reported at 0 ; 8 and 1 ; 0 predicted vocabulary development at 1 ; 0 and 2 ; 0. In support of previous findings with smaller, often less representative samples, gesture and object use at 1 ; 0 were better predictors of 2 ; 0 vocabulary than were gesture and object use at 0 ; 8. At 1 ; 0, children from the lower SES groups were reported to understand more words than children from the higher SES groups, but there were no SES differences for words produced at 1 ; 0 or 2 ; 0. The findings add to our understanding of the variability in the development of early communicative behaviours.
Social and political thresholds in Stockholm,c.1720–1770
Authors: SENNEFELT KARIN
Published: June 2008

This article explores the significance of mobility in the everyday structures of political life through a case study of political space in mid-eighteenth-century Stockholm. Analytical in approach, the study focuses on political action in public space, in its spatial negotiations of inclusion and exclusion, and investigates three particular places: the city itself, the central square Riddarhustorget and the city's wine shops. It shows that temporary political density and geographical proximity during meetings of the Estates of the Realm, when a large influx of people upset the corporate social division of the city, gave the lower orders the opportunity to cross thresholds into elite places. In addition, mobility between sites and the use of many places, rather than the mastering of one particular site, was a means for these orders to take part in political life. Results show that a unified ‘public sphere’ was not a prerequisite for extra-parliamentary politics. Instead, participation was made possible by moving between places, and learning how to navigate many different social and political boundaries.
From German-speaking Catholics to French carpenters: Strasbourg guilds and the role of confessional boundaries in the inclusion and exclusion of foreigners in the eighteenth century
Authors: SONKAJÄRVI HANNA
Published: June 2008

This article deals with the importance of religion as a factor influencing the inclusion and exclusion of foreigners from – and inside – the guilds in eighteenth-century Strasbourg. We consider the different notions of theétrangeras socially constructed and circumstantial. Together with factors such as social status, family ties, gender, systems of patronage, wealth, language and the citizenship rights of a town, religious and denominational boundaries constituted a major factor for influencing the inclusion and exclusion of foreigners in the early modern society. The construction and preservation of such boundaries are explored here through the examples of the carpenters' and the shipmen's guild found in the eighteenth-century multiconfessional city of Strasbourg.
Urban history in the new South Africa: continuity and innovation since the end of apartheid
Authors: BICKFORD-SMITH VIVIAN
Published: June 2008

The Soweto uprising of 1976 confirmed to most observers that the anti-apartheid struggle (in contrast to anti-colonial struggles in many other parts of Africa) would be largely urban in character. This realization gave impetus to a rapid growth in the hitherto small field of South African urban history. Much new work predictably sought to understand the nature of conflict and inequality in South African cities and its possible resolution.
Expression and biological activity assay of bovine interleukin-18 fusion protein
Authors: Zhao-Ju Tian , Yu-Shu Zheng , Cui-Yan Liu , Jing-Dong Hu , Hong-Kun Zhao
Published: June 2008

The cDNA of bovine interleukin-18 (BoIL-18) was subcloned into pGEX6P-1 vector and transformed into Escherichia coli BL21(DE3). The recombinant protein was successfully expressed in E. coli by induction of isopropyl β-d-1-thiogalactopyranoside (IPTG) at 0.3 mmol/l for 8 h. SDS-PAGE indicated that the BoIL-18 fusion protein, 44 kDa, was highly expressed. Densitometric scanning showed that the fusion protein expression was about 31.8% of the total bacterial protein. The biological activity of the chromatographically purified protein was assayed. The peripheral blood mononuclear cells (PBMC) proliferation test indicated that the BoIL-18 fusion protein could enhance PBMC proliferation when its concentration was more than 0.10 mg/l. Enzyme-linked immunosorbent assay (ELISA) showed that the BoIL-18 fusion protein could induce interferon (IFN)-γ production from spleen lymphocytes when it was at a concentration of more than 0.20 mg/l, and that the inducing effect of BoIL-18 fusion protein on IFN-γ was directly proportional to its concentration. This verified that the purified BoIL-18 fusion protein possessed a functional activity and could be applied in further studies.
Lentiviral vector transfection of chicken embryo primordial germ cells in vitro
Authors: Hong-Mei Ding , Shi-Yong Xu , Gen-Bao Shao , Yan Sun , Meng Wang , Hong-Lin* Liu
Published: June 2008

Lentiviruses as gene transfer vectors have been used successfully to transfect mammal embryonic stem cells and germline stem cells, but this has not been attempted in avian primordial germ cells (PGCs). PGCs were isolated from the gonads of Isa-brown chicken embryos at stage 28 and co-cultured with gonadal stroma cells. A lentiviral vector pLenti-CMV-EGFP was constructed and the virus harvested by cotransfecting 293FT cells with the vector and packaging plasmids. Concentrated lentiviruses were used to transfect chicken PGCs, the transfection efficiency was up to 24.19%.
Screening, cloning and sequence analysis ofgBTN1A1gene in mammary gland of Xinong Saanen goat
Authors: Li-Juan Zhang , Hui-Juan Wu , Jun Luo , Jun-Xia Liu , Ning Zhang , Hai-Bing Wang , Cui-Yan Shan , Gang Yu
Published: June 2008

Butyrophilin 1A1 (BTN1A1), which is a member of the Ig superfamily, is highly expressed in the lactating mammary gland and is secreted into milk in association with lipid droplets, and concentrated in the apical plasma membranes of mammary epithelial cells. Because butyrophilin is expressed only during lactation, it appears to be essential for milk fat globule production. However, there is little information about its properties in the dairy goat. The objective of this study was to confirm whether butyrophilin was related to milk changes in different lactation periods of Xinong Saanen goats. Using suppression subtractive hybridization analysis, we identified a significant increase in butyrophilin mRNA in Xinong Saanen goat mammary gland at middle lactation when compared to that of late lactation. The gBTN1A1 complementary DNA has an open reading frame of 1581 nucleotides encoding a putative protein of 526 amino acids. Amino acids 1–26 were the signal peptide domain. The homologies of nucleotide and peptide sequences of goat butyrophilin with bovine (NM_174508), human (NM_001732) and mouse (AK145168) butyrophilin were 97 and 96%, 88 and 84%, 84 and 70%, respectively. The secondary structure, transmembrane domain and hydrophilicity of goat butyrophilin were similar to the those of the bovine, human and mouse protein. In conclusion, we confirmed that the goat mammary gland mRNA level of gBTN1A1 was responsible for goat milk fat globule secretion.
RAPD analysis on genetic diversity of typical tea populations in Hunan Province
Authors: Cheng-Wen Shen , Yi-Huan Huang , Jian-An Huang , Jun-Wu Luo , Chun-Lin Liu , De-Hua Liu
Published: June 2008

Genetic diversity and genetic variation of 240 adult plants of four tea populations in Hunan – Camellia sinensis var. sinensis, C. sinensis var. assamica cv. Duntsa, C. ptilophylla and C. sinensis var. assamica cv. Jianghua – were studied by rapid amplification of polymorphic DNA (RAPD) markers. The results showed 226 loci using 21 random primers (10 bp), of which 201 (88.9%) were polymorphic. The genetic diversity analysis indicated that Shannon's index was 0.43; 74.7% of which was within-population genetic diversity while 25.3% was among-population variation. The gene diversity indexes of total populations (HT), within populations (HS) and among populations (HST) were, respectively, 0.37, 0.28 and 0.09. The coefficient of gene differentiation (GST) among populations was 0.23, indicating a 76.7% variation within populations and 23.3% among populations. These results displayed a rich within-population genetic variation, as in Shannon's diversity index. Interpopulation gene flow (Nm) was 0.74, which indicates the limited genetic exchange between populations.
Bacillus thuringiensiscrystal protein toxicity against plant-parasitic nematodes
Authors: Zi-Quan Yu , Qian-Lan Wang , Bin Liu , Xue Zou , Zi-Niu Yu , Ming Sun
Published: June 2008

A bioassay method was developed to use the parasporal crystal protein ofBacillus thuringiensisagainst plant-parasitic nematodes. Using this method, the parasporal crystal proteins of tenBtstrains showed activity against plant-parasitic nematodes. The toxicity of YBT-021 againstMeloidogyne hapla,Pratylenchus scribneri,Tylenchorhynchussp.,Ditylenchus destructorandAphelenchoidessp. was also assayed. The resulting LC50values were 35.62 μg/ml, 75.65 μg/ml, 94.31 μg/ml, 215.21 μg/ml and 128.76 μg/ml, respectively.
Expression of modified VHb gene and fused insectidal gene in tobacco
Authors: You-Ru Wang , Hong-Zhi Cui , San-Dui Guo
Published: June 2008

The highly efficient plant binary expression vector pGBIF4ABCVHB was constructed using the artificially modified, synthesized VHb gene and fused insectidal gene (GFMcryIA and CPTI). Transgenic tobacco plants were obtained by Agrobacterium-mediated transformation. For 32 plants, the bivalent genes were inserted successfully into the tobacco genome and detected by polymerase chain reaction (PCR) amplification. Southern blot and Western blot analyses showed that VHb gene was expressed in the transgenic plants. Toxicity assay indicated that the fused insectidal gene expressed pesticidal toxin protein. The net weight of transgenic tobacco plants exceeded that of non-transgenic ones by 8%. Compared to non-transgenic tobacco plants, transgenic plants appeared to be high-yielding, insect-resistant varieties.
Construction of conjugal transfer system of Streptomyces cinnamonensis and effect of PCR-mediated nsdA gene disruption on its secondary metabolism
Authors: Fen Chen , Wei Xiong , Yong Min , Yu-Qing Fan , Yun-Xiang Liang , He-Ping Lü , Ren-Chang Xing , Ying-Hua Zheng
Published: June 2008

Intergeneric transfer of plasmid vectors pSET152 and pHL212 from donor Escherichia coli ET12567/pUZ8002 and S17-1 to Streptomyces cinnamonensis was demonstrated and optimized. Assisted by this conjugation system, nsdA gene disruption was achieved through PCR-targeted gene replacement. One AprRKanS exconjugant BIB309 was then isolated and confirmed to be the nsdA null mutant. Compared with the starting strain, monensin production by the nsdA− mutant BIB309 increased 270% in vitro.
THE ENLIGHTENMENT ON TRIAL: STATE SERVICE AND SOCIAL DISCIPLINE IN EIGHTEENTH-CENTURY GERMANY'S PUBLIC SPHERE
Authors: SAUTER MICHAEL J.
Published: June 2008

Prussia's Edict on Religion of 1788 forbade sermons that undermined popular belief in the Holy Trinity and the Bible. Scholars have assumed that this act was counter-enlightened because it limited the free use of reason in public. An analysis of two court cases related to the edict reveals, however, that both the edict and its “enlightened” opponents within the state assumed that public expression should be disciplined. With respect to the enlightened bureaucratic elite that opposed the edict, it identifies two factors that impelled them toward the disciplining of public communication: 1) German universities created an elite social group that assiduously cultivated its own intellectual sphere, and 2) having access to state power gave each member of the elite something to lose if the process of the Enlightenment proved politically or socially destabilizing. As a result, the fight over the Edict on Religion cannot be understood in terms of an Enlightenment/counter-Enlightenment dichotomy, but must be seen as a debate within the German elite about the level of social discipline that was sufficient for maintaining domestic tranquility.
INTEGRATING MUSIC INTO INTELLECTUAL HISTORY: NINETEENTH-CENTURY ART MUSIC AS A DISCOURSE OF AGENCY AND IDENTITY
Authors: TOEWS JOHN E.
Published: June 2008

Few intellectual historians of nineteenth-century Europe would deny that the tradition of art music that evolved between the revolutionary watershed at the end of the eighteenth century and the international wars and domestic convulsions of the first half of the twentieth century—a body of musical works from Haydn and Mozart to Mahler and Strauss that has been passed down to us in canonized form as the “imaginary museum” of “classical music” —was an enormously significant dimension of European cultural and intellectual history, especially in German-speaking central Europe. In the territories of the German Confederation, the Kingdom of Prussia and the Habsburg Empire, and later in the German and Austro-Hungarian Empires, the production, performance and consumption of classical music was not just an important element in the history of aesthetic and cultural forms but also a privileged site for imagining and enacting the organization of individuals into historical subjects (theBildungof modern individuals) and for the integration of individuals into collectivities through processes of subjective identification. Broad interest in the relations between agency and identity among historians, including European intellectual historians, should have drawn many of them, one would have thought, toward investigation of the ways the cultural work undertaken by music was connected to, and interacted with, the cultural role of the textual and visual arts, or of how musical performance and experience helped European individuals organize and perform their self-activity and self-consciousness in relation to the past, to other individuals within the networks of communal relations, and to the transcendent. The history of music would appear to be critical for understanding historical experiences of the relations between memory and expectation at both the individual and communal levels.
WHERE IS KARL BARTH IN MODERN EUROPEAN HISTORY?
Authors: KOSHAR RUDY
Published: June 2008

Anglophone historians of modern Europe know Karl Barth primarily as the intellectual leader of the anti-Nazi Church Struggle and the principle author of the Barmen Declaration of 1934, which spoke a dramatic “No” to National Socialism's attack on the German churches. But Barth was also arguably the most important—and most prolific—theologian of the twentieth century. Aside from his unfinished magnum opus, the fourteen-volumeChurch Dogmatics, he published more than one hundred books and articles, and he quite literally wrote until the day he died in 1968. Barth's output has elicited an equally impressive secondary literature, produced mostly by students of theology and amounting to around fourteen thousand titles in twenty-five languages. As might be expected, theologians differ in their interpretations of Barth, seeing him as a formative voice in “neo-orthodox” Protestantism, a left-wing socialist, a fitting subject of deconstructionist philosophical theology, a thinker who showed the way “past the modern,” or a “critically realistic dialectical theologian.” In view of this record it may come as a surprise to find that until recently the Swiss was still “habitually honored but not much read,” as theologian George Hunsinger wrote in 1991. Hunsinger was not the only observer to see that Barth's work was never fully integrated into the corpus of theological culture in Europe and the United States despite the scholarly interest in his thought. This situation may be changing, as a transatlantic “Barth renaissance” now gathers momentum, nearly forty years after the great theologian's death.
Urteilsfähigkeit als Voraussetzung für Aufklärung und Einwilligung
Authors: Dittmann Volker
Published: June 2008

Diagnostische oder therapeutische medizinische Eingriffe benötigen eine Rechtsgrundlage. Diese besteht in der Regel in der ausdrücklichen Einwilligung des Patienten nach angemessener Aufklärung. Voraussetzung für Aufklärung und Einwilligung ist die Urteilsfähigkeit. Sie ist grundsätzlich gegeben, wenn keine erhebliche psychische Störung vorliegt, dies ist im Rahmen des Aufklärungsgesprächs vom Arzt nach den Kriterien der allgemeinen Psychopathologie zu überprüfen.
Körperliche und sexuelle Gewalt an Erwachsenen – vom forensischen Denken und ärztlichen Handeln
Authors: Klopfstein Ursula , Streit Sven , Schön Corinna A.
Published: June 2008

Körperliche und sexuelle Gewalt an erwachsenen Personen ist ein aktuelles und relevantes Thema in der ärztlichen Praxis. Der Artikel fasst die verschiedenen Gewaltformen wie häusliche Gewalt, öffentliche Gewalt, Unfälle und Selbstverletzungen zusammen und geht dann vertieft auf die forensisch-medizinischen Aspekte des ärztlichen Handelns in Zusammenhang mit Gewaltopfern ein. Hierbei stehen die Erkennung von Verletzungen durch körperliche und sexuelle Gewalt und die Besonderheiten der forensischen Dokumentation im Vordergrund.
Der plötzliche Tod im Kindesalter
Authors: Hausmann Roland
Published: June 2008

Der plötzliche Kindstod (SIDS) stellt in den Industrieländern die häufigste Todesursache in der Postneonatalperiode dar. Die Inzidenz ist in den letzten Jahren rückläufig und liegt derzeit unter 0.5 von 1000 Lebendgeborenen. Die Ätiologie des SIDS ist nach wie vor ungeklärt. Vermutet wird ein Erstickungsvorgang, ausgelöst durch ein zentrales Atemversagen, CO2-Rückatmung oder Verlegung der Atemwege. Als weitere pathophysiologische Faktoren werden Hyperthermie sowie zentrale Störungen der Schlaf- und Aufwachreaktion diskutiert. Zu den wichtigsten Risikofaktoren gehören Bauchlage, Frühgeburtlichkeit, Rauchen und Drogenkonsum der Mutter während der Schwangerschaft, Stillverzicht, Alter der Mutter < 18 Jahre und Wärmebelastung des Kindes. Beim SIDS handelt es sich nicht um eine Entität, sondern um die deskriptive Bezeichnung für eine Gruppe von plötzlich und unerwartet eintretenden Säuglingstodesfällen, deren Ursache sich mit den derzeit zur Verfügung stehenden Methoden nicht nachweisen lässt (Ausschlussdiagnose). Die forensische Bedeutung des plötzlichen Kindstodes resultiert nicht nur aus seiner relativen Häufigkeit, sondern insbesondere aus den in jedem Einzelfall zu erwägenden Differentialdiagnosen. So müssen durch Obduktion und umfassende postmortale Zusatzuntersuchungen (histologische, toxikologische, mikrobiologische / virologische Untersuchungen) unter Einbeziehung der Umstände am Auffindeort und der klinischen Anamnese andere natürliche und insbesondere nicht-natürliche Todesursachen abgeklärt werden.
A German Adaptation of the UPPS Impulsive Behavior Scale: Psychometric Properties and Factor Structure
Authors: Schmidt Ralph E. , Gay Philippe , d’Acremont Mathieu , Van der Linden Martial
Published: June 2008

Impulsivity occupies a prominent place in psychopathology, yet the precise nature of its implication in mental disorders is still poorly understood. This is partly due to inconsistencies among existing conceptualizations and measurements of impulsivity. In an attempt to overcome these inconsistencies, S. P. Whiteside and D. R. Lynam (2001) developed the UPPS Impulsive Behavior Scale, which distinguishes four facets of impulsivity: urgency, lack of premeditation, lack of perseverance, and sensation seeking. The present study examined the psychometric properties of a German adaptation of the UPPS Impulsive Behavior Scale by administering it to a sample of psychology students. Exploratory and confirmatory factor analyses of the responses of 310 native German speaking participants suggested a four-factor solution similar to that found in the original study. Results indicated that these four subscales possess very good internal consistency.
Scientific Problem Solving in a Virtual Laboratory: A Comparison Between Individuals and Pairs
Authors: Métrailler Yolanda A. , Reijnen Ester , Kneser Cornelia , Opwis Klaus
Published: June 2008

This study compared individuals with pairs in a scientific problem-solving task. Participants interacted with a virtual psychological laboratory called Virtue to reason about a visual search theory. To this end, they created hypotheses, designed experiments, and analyzed and interpreted the results of their experiments in order to discover which of five possible factors affected the visual search process. Before and after their interaction with Virtue, participants took a test measuring theoretical and methodological knowledge. In addition, process data reflecting participants’ experimental activities and verbal data were collected. The results showed a significant but equal increase in knowledge for both groups. We found differences between individuals and pairs in the evaluation of hypotheses in the process data, and in descriptive and explanatory statements in the verbal data. Interacting with Virtue helped all students improve their domain-specific and domain-general psychological knowledge.
A Psycholinguistic Investigation of Football Players’ Mental Representations of Game Situations: Does Expertise Count?
Authors: Gygax Pascal M. , Wagner-Egger Pascal , Parris Ben , Seiler Roland , Hauert Claude-Alain
Published: June 2008

In order to progress through a competitive sporting event, athletes need to form mental representations of the situations they encounter. In this paper, we present three experiments exploring the mental representations of football players when presented with written material describing football game situations. Experiment 1 assessed off-line processing by having players of different levels generate written football scripts. The results predominantly showed that players of lower expertise were less “other-oriented” and included more emotional elements in their mental representations. Experiments 2a and 2b further explored these differences. Using an on-line measure, a reading-time paradigm, we showed that First Division players’ mental representations more easily included “others” and less readily included emotions, as opposed to both National League and Fifth Division players. Although Fifth Division and National League were similar, different cognitive processes may underlie the construction of the players’ mental representations.
Mixing‐induced precipitation: Experimental study and multiscale numerical analysis
Authors: Tartakovsky A. M. , Redden G. , Lichtner P. C. , Scheibe T. D. , Meakin P.
Published: June 2008

Laboratory experiments, pore‐scale simulations, and continuum (Darcy) ‐scale simulations were used to study mixing‐induced precipitation in porous media. In the experimental investigation, solutions containing Na2CO3 and CaCl2 were each injected in different halves of a quasi two‐dimensional flow cell filled with quartz sand. As a result of the in situ mixing between the two solutions, a narrow calcite precipitate layer (less than 5 mm wide) of more or less uniform width was formed between the individual solutions. Pore‐scale simulations were conducted to help understand the mechanism of precipitation layer formation. The effect of the Peclet number, Pe, and the Damköhler number, Da, on mixing induced precipitation was also investigated. Pore‐scale simulations revealed the presence of large pore‐scale concentration gradients. This, and the presence of features, such as the precipitation layer, with characteristic lengths on the order of the average sand grain diameter, indicate the absence of a clear scale separation required for the strict derivation of Darcy‐scale advection‐dispersion equations. Nevertheless, we found that an adaptive high‐resolution model based on advection‐dispersion equations with grid sizes in the mixing zone smaller than the size of the sand grains can qualitatively reproduce the essential features of the experiment. As an alternative to computationally expensive high‐resolution simulations, we proposed new forms for the homogeneous and heterogeneous reaction terms in Darcy‐scale advection dispersion equations. These terms involve transport and mixing indices that account for highly nonuniform pore‐scale concentration distributions and highly localized reactions. The proposed model accurately estimates the changes in solute concentrations due to homogenous and heterogeneous reactions during precipitation of minerals, observed in the pore‐scale simulations, while conventional low‐resolution advective‐dispersion equations produced erroneous results.
Characterizing subpixel variability of low resolution radiometer derived soil moisture using high resolution radar data
Authors: Narayan Ujjwal , Lakshmi Venkat
Published: June 2008

Soil moisture estimates obtained using passive remote sensing from satellite platforms often suffer from the drawback of coarse spatial resolution. In this current work, low resolution soil moisture estimates from passive remote sensing are fused with high resolution radar backscatter data to produce soil moisture change estimates at the spatial resolution of radar. More specifically, soil moisture estimated from AMSR‐E and TMI (separate cases) for a single 50 km × 50 km pixel has been fused with TRMM‐PR backscatter data at 5 km resolution to produce soil moisture change estimates at 5 km resolution. A brief sensitivity analysis has been presented as a baseline study for soil moisture sensitivity of TRMM‐PR backscatter. Soil moisture change estimates have been computed using a simple methodology and validated using in situ measurements from the Little Washita Micronet. It is seen that fusing radar data with radiometer soil moisture estimates leads to a better representation of the soil moisture variability within the radiometer pixel as compared to the baseline (radiometer estimate only) case where uniform subpixel distribution of soil moisture is assumed. The TMI/PR case performs better than the AMSR‐E/PR case indicating the need for temporally coincident radar radiometer observations for producing high resolution soil moisture change estimates.
Deep countercurrent beneath the Kuroshio in the Okinawa Trough
Authors: Nakamura Hirohiko , Nishina Ayako , Ichikawa Hiroshi , Nonaka Masami , Sasaki Hideharu
Published: June 2008

The Okinawa Trough is geographically separated into the northern and southern parts by the Kerama Gap, and the northern part is composed of the northern, central and southern subbasins formed by bights of the continental slope. Previous observations have indicated that a deep countercurrent is present beneath the Kuroshio on the continental slope in the northern Okinawa Trough. However, its persistence over time and its spatial structure over the entire basin have not been clarified to date. The present study examines moored current meter data on the continental slope in the southern and central subbasins of the northern Okinawa Trough for November 2004 to November 2006. Deep flows on the continental slope have a clear seasonality in the southern subbasin; eddy motions due to Kuroshio meanders are organized into a persistent countercurrent below the Kuroshio in the winter‐spring period. During this time, high‐frequency Kuroshio meanders with periods near 10 d are likely to diminish in the southern subbasin while low‐frequency Kuroshio meanders with periods of 1–3 months tend to dominate in the northern subbasin. In addition, a high‐resolution ocean general circulation model is used to explore the deep flow field over the entire Okinawa Trough. The model indicates that the deep flow field is stable in the southern Okinawa Trough over the year, whereas it is unstable in the northern Okinawa Trough particularly in the winter‐spring period. This results in a persistent countercurrent driven by cyclonic eddies on the continental slope in the northern Okinawa Trough.
Atmospheric CO2 in situ measurements: Two examples of Crown Design flights in NE Spain
Authors: Font A. , Morguí J. A. , Rodó X.
Published: June 2008

The new “Crown” aircraft sampling (CAS) approach integrates CO2 data obtained through horizontal transects and vertical profiles, sampling a specific volume of air at different atmospheric sections: 600 m, 1200 m, and 2500 m above the sea level (masl). This approach provides new tools to model fluxes in relation with meteorological conditions. It has been applied over a plain in the basin of the river called Ebre in the North East of Spain, with a triangular section defined by Linyola, Mequinensa's dam and Binèfar, taking up 1500 km2. The main human activity is agriculture, either irrigated or dry land. Horizontal transects at 600 and 1200 masl were sampled for CO2, with vertical profiles at the vertexes from 600 to 2500 masl (ground level is around 400 masl). The three‐dimensional configuration of the CAS Design enables the study of the CO2 fluxes between sections. Data have been obtained on a monthly basis since February 2006 until nowadays. In order to study the influence of forced turbulence in the atmospheric CO2 spatial distribution, two data sets are examined: the flight of 7 February 2006, performed under stable anticyclonic weather conditions; and the 6 March 2006 flight, characterized by strong northerly winds. The presence of stable/unstable layers in the February flight resulted in a stepwise vertical distribution of CO2 (with an increase from the free troposphere, 383 ppmv, to 400 ppmv close to the ground) whereas the unstable low troposphere sampled in March 2006 provided flat CO2 vertical profiles (concentrations ranging from 385 to 387 ppmv). In regard to the variability in the horizontal sections, the calculation of the Hurst exponents (H) provides a way to measure the persistence of vertical transport along the horizontal transects. In the February flight, CO2 concentration in transects shows the imprint of a spreading vertical transport from land (H > 0.90) but it is partially wiped away by high turbulence levels in the March flight (H = 0.79). From these results we expect CAS Design to provide better estimates of CO2 fluxes in the future.
A Multisensor satellite‐based assessment of biomass burning aerosol radiative impact over Amazonia
Authors: Patadia Falguni , Gupta Pawan , Christopher Sundar A. , Reid Jeffrey S.
Published: June 2008

Using spatially and temporally collocated multispectral, multiangle and broadband data sets from the Terra satellite, the role of biomass burning (BB) smoke particles on cloud‐free top of atmosphere (TOA) direct shortwave aerosol radiative forcing (SWARF) is examined. A 5‐year analysis during the peak biomass burning months of August and September is presented over South America (0°–20°S and 45°W–65°W). Our results indicate that over 5 years, the TOA diurnally averaged SWARF (DSWARF) from the Clouds and the Earth's Radiant Energy System (CERES) scanner ranges between −5.2 Wm−2and −9.4 Wm−2with a mean value of −7.6 Wm−2and an estimated uncertainty of ±1.4 Wm−2. The corresponding Multi Angle Spectroradiometer (MISR) aerosol optical thickness (AOT at 0.558μm) ranged from 0.15 to 0.36 with a mean value of 0.24. The estimated mean TOA aerosol radiative forcing efficiency (Eτ) is −44.2 Wm−2τ−1and is in good agreement with previous studies. We also examined the beta versions of the MISR data products such as the angstrom exponent (AE) and fraction of AOT in different size bins to assess the role of BB aerosol particle properties on SWARF. Our analysis indicates that the MISR retrieved 5 year mean AE is 1.54. Contribution to total AOT from small, medium and large particles is 66%, 16% and 18% respectively. This is the first multiyear assessment of SWARF for biomass burning aerosol particles using satellite observations alone and should serve as a useful constraint for numerical modeling simulations that estimate SWARF.
Diurnal and vertical variability of the sensible heat and carbon dioxide budgets in the atmospheric surface layer
Authors: Casso‐Torralba Pau , Vilà‐Guerau de Arellano Jordi , Bosveld Fred , Soler Maria Rosa , Vermeulen Alex , Werner Cindy , Moors Eddy
Published: June 2008

The diurnal and vertical variability of heat and carbon dioxide (CO2) in the atmospheric surface layer are studied by analyzing measurements from a 213 m tower in Cabauw (Netherlands). Observations of thermodynamic variables and CO2mixing ratio as well as vertical profiles of the turbulent fluxes are used to retrieve the contribution of the budget terms in the scalar conservation equation. On the basis of the daytime evolution of turbulent fluxes, we calculate the budget terms by assuming that turbulent fluxes follow a linear profile with height. This assumption is carefully tested and the deviation from linearity is quantified. The budget calculation allows us to assess the importance of advection of heat and CO2during day hours for three selected days. It is found that, under nonadvective conditions, the diurnal variability of temperature and CO2is well reproduced from the flux divergence measurements. Consequently, the vertical transport due to the turbulent flux plays a major role in the daytime evolution of both scalars and the advection is a relatively small contribution. During the analyzed days with a strong contribution of advection of either heat or carbon dioxide, the flux divergence is still an important contribution to the budget. For heat, the quantification of the advection contribution is in close agreement with results from a numerical model. For carbon dioxide, we qualitatively corroborate the results with a Lagrangian transport model. Our estimation of advection is compared with traditional estimations based on the Net Ecosystem‐atmosphere Exchange (NEE).
Tidal excitation of elliptical instability in the Martian core: Possible mechanism for generating the core dynamo
Authors: Arkani‐Hamed J. , Seyed‐Mahmoud B. , Aldridge K. D. , Baker R. E.
Published: June 2008

We propose a causal relationship between the creation of the giant impact basins on Mars by a large asteroid, ruptured when it entered the Roche limit, and the excitation of the Martian core dynamo. Our laboratory experiments indicate that the elliptical instability of the Martian core can be excited if the asteroid continually exerts tidal forces on Mars for ∼20,000 years. Our numerical experiments suggest that the growth‐time of the instability was 5,000–15,000 years when the asteroid was at a distance of 50,000–75,000 km. We demonstrate the stability of the orbital motion of an asteroid captured by Mars at a distance of 100,000 km in the presence of the Sun and Jupiter. We also present our results for the tidal interaction of the asteroid with Mars. An asteroid captured by Mars in prograde fashion can survive and excite the elliptical instability of the core for only a few million years, whereas a captured retrograde asteroid can excite the elliptical instability for hundreds of millions of years before colliding with Mars. The rate at which tidal energy dissipates in Mars during this period is over two orders of magnitude greater than the rate at which magnetic energy dissipates. If only 1% of the tidal energy dissipation is partitioned to the core, sufficient energy would be available to maintain the core dynamo. Accordingly, a retrograde asteroid is quite capable of exciting an elliptical instability in the Martian core, thus providing a candidate process to drive a core dynamo.
Reducing antenna mechanical noise in precision spacecraft tracking
Authors: Armstrong J. W. , Estabrook F. B. , Asmar S. W. , Iess L. , Tortora P.
Published: June 2008

Doppler tracking of deep space probes is central to spacecraft navigation and many radio science investigations. The most sensitive Doppler observations to date were taken using the NASA/JPL Deep Space Network antenna DSS 25 (a 34 m diameter beam‐waveguide station instrumented with simultaneous X‐ and Ka‐band uplink and tropospheric scintillation calibration equipment) tracking the Cassini spacecraft. Those observations achieved Doppler fractional frequency stability (Doppler frequency fluctuation divided by center frequency, Δf/fo) ≈ 3 X 10−15 at 1000 s integration time. The leading noise in these very‐high‐sensitivity tracks was time‐dependent unmodeled motion of the ground antenna's phase center (caused, e.g., by antenna sag as elevation angle changes, unmodeled subreflector motion, wind loading, bulk motion of the antenna as it rolled over irregularities in its azimuth ring, etc.). This antenna mechanical noise has seemed irreducible since it is not clear how to build a large, moving, steel structure with intrinsic mechanical stability better than that of current tracking stations. Here we show how intrinsic mechanical noise of a large tracking antenna can be suppressed when two‐way Doppler tracking data and receive‐only Doppler data from a stiffer antenna are combined with suitable delays. Using this time delay correction procedure, the mechanical noise in the final Doppler observable can be reduced to that of the stiffer antenna. We demonstrate proof‐of‐concept experimentally and briefly discuss some practical considerations.
Fault growth and propagation during incipient continental rifting: Insights from a combined aeromagnetic and Shuttle Radar Topography Mission digital elevation model investigation of the Okavango Rift Zone, northwest Botswana
Authors: Kinabo B. D. , Hogan J. P. , Atekwana E. A. , Abdelsalam M. G. , Modisi M. P.
Published: June 2008

Digital Elevation Models (DEM) extracted from the Shuttle Radar Topography Mission (SRTM) data and high‐resolution aeromagnetic data are used to characterize the growth and propagation of faults associated with the early stages of continental extension in the Okavango Rift Zone (ORZ), northwest Botswana. Significant differences in the height of fault scarps and the throws across the faults in the basement indicate extended fault histories accompanied by sediment accumulation within the rift graben. Faults in the center of the rift either lack topographic expressions or are interpreted to have become inactive, or have large throws and small scarp heights indicating waning activity. Faults on the outer margins of the rift exhibit either (1) large throws or significant scarp heights and are considered older and active or (2) throws and scarp heights that are in closer agreement and are considered young and active. Fault linkages between major fault systems through a process of “fault piracy” have combined to establish an immature border fault for the ORZ. Thus, in addition to growing in length (by along‐axis linkage of segments), the rift is also growing in width (by transferring motion to younger faults along the outer margins while abandoning older faults in the middle). Finally, utilization of preexisting zones of weakness allowed the development of very long faults (>100 km) at a very early stage of continental rifting, explaining the apparent paradox between the fault length versus throw for this young rift. This study clearly demonstrates that the integration of the SRTM DEM and aeromagnetic data provides a 3‐D view of the faults and fault systems, providing new insight into fault growth and propagation during the nascent stages of continental rifting.
Subduction dynamics as revealed by trench migration
Authors: Lallemand Serge , Heuret Arnauld , Faccenna Claudio , Funiciello Francesca
Published: June 2008

New estimates of trench migration rates allow us to address the dynamics of trench migration and back‐arc strain. We show that trench migration is primarily controlled by the subducting plate velocity Vsub, which largely depends on its age at the trench. Using the hot and weak arc to back‐arc region as a strain sensor, we define neutral arcs characterized by the absence of significant strain, meaning places where the forces (slab pull, bending, and anchoring) almost balance along the interface between the plates. We show that neutral subduction zones satisfy the kinematic relation between trench and subducting plate absolute motions: Vt = 0.5Vsub − 2.3 (in cm a−1) in the HS3 reference frame. Deformation occurs when the velocity combination deviates from kinematic equilibrium. Balancing the torque components of the forces acting at the trench indicates that stiff (old) subducting plates facilitate trench advance by resisting bending.
Probability distribution function of the upper equatorial Pacific current speeds
Authors: Chu Peter C.
Published: June 2008

The probability distribution function (PDF) of the upper (0–50 m) tropical Pacific current speeds (w), constructed from hourly ADCP data (1990–2007) at six stations for the Tropical Atmosphere Ocean project, satisfies the two‐parameter Weibull distribution reasonably well with different characteristics between El Nino and La Nina events: In the western Pacific, the PDF of w has a larger peakedness during the La Nina events than during the El Nino events; and vice versa in the eastern Pacific. However, the PDF of w for the lower layer (100–200 m) does not fit the Weibull distribution so well as the upper layer. This is due to the different stochastic differential equations between upper and lower layers in the tropical Pacific. For the upper layer, the stochastic differential equations, established on the base of the Ekman dynamics, have analytical solution, i.e., the Rayleigh distribution (simplest form of the Weibull distribution), for constant eddy viscosity K. Knowledge on PDF of w during the El Nino and La Nina events will improve the ensemble horizontal flux calculation, which contributes to the climate studies.
Oxygen declines and the shoaling of the hypoxic boundary in the California Current
Authors: Bograd Steven J. , Castro Carmen G. , Di Lorenzo Emanuele , Palacios Daniel M. , Bailey Helen , Gilly William , Chavez Francisco P.
Published: June 2008

We use hydrographic data from the California Cooperative Oceanic Fisheries Investigations program to explore the spatial and temporal variability of dissolved oxygen (DO) in the southern California Current System (CCS) over the period 1984–2006. Large declines in DO (up to 2.1 μmol/kg/y) have been observed throughout the domain, with the largest relative DO declines occurring below the thermocline (mean decrease of 21% at 300 m). Linear trends were significant (p < 0.05) at the majority of stations down to 500 m. The hypoxic boundary (∼60 μmol/kg) has shoaled by up to 90 m within portions of the southern CCS. The observed trends are consistent with advection of low‐DO waters into the region, as well as decreased vertical oxygen transport following near‐surface warming and increased stratification. Expansion of the oxygen minimum layer could lead to cascading effects on benthic and pelagic ecosystems, including habitat compression and community reorganization.