bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of diet transition on serum calcium and phosphorus and fatty acids in Zoo giraffe (Giraffa camelopardalis)
Authors: Koutsos E.A. , Armstrong D. , Ball R. , Dikeman C. , Hetherington J. , Simmons L. , Valdes E.V. , Griffin M.
Published: October 2010

In response to new recommendations for feeding giraffe in zoos, giraffe (n = 6) were transitioned from a typical hoofstock diet to diets containing reduced starch, protein, Ca and P and added n3 fatty acids. This diet was fed as a 50:50 mix with alfalfa and grass hay. Over the next 4 years, serum Ca, P, and fatty acids were measured every 6 months (summer and winter). Serum Ca was not affected by season (P = 0.67) or by diet (P = 0.12). Serum P was not affected season (P = 0.14), but was reduced by diet (P<0.01), and serum Ca:P was also increased by diet (P<0.01). The ratio of serum Ca:P tended to be affected by season (P = 0.07), in which animals tended to have greater Ca:P during the summer vs. the winter. The diet transition resulted in reduced serum saturated fatty acids (including lauric, myristic, palmitic, arachidic, and behenic acids), and increases in n6 fatty acids (including linolenic and arachidonic acids) and n3 fatty acids (docosahexaenoic acid) (P<0.05 for each). Overall, this diet transition resulted in blood nutrient profiles that more closely match that of values found in free‐ranging giraffe. Zoo Biol 30:523–531, 2011. © 2010 Wiley Periodicals, Inc.
All Quiet on the Eastern Front?—Temporary contract migration in Asia revisited from a development perspective
Authors: Piper Nicola
Published: October 2010

Although as such not new, the revival or continuation as well as expansion of temporary contract schemes as the main method by which to regulate economic migration legally is part and parcel of a new discourse on migration policy making: ‘management of migration’. Furthermore, this discourse and concomitant policy descriptions are related to the current phase of the debate on the relationship between migration and development. The focus on managing migration in its link to development revolves around the idea that orderly, legal migration schemes can benefit sending and receiving countries’ developmental and labour market needs as well as individual migrants themselves. The welfare and rights of migrant workers, however, remain the neglected dimension in this equation. As preference is given to temporary or circular migration policies, while little attention is paid to migrants’ rights beyond the rhetorical level, the question which arises pertains to migrants’ actual capability to contribute to development. In the attempt to address this question, the normative starting point of this paper is a rights-based approach to migration and development. The argument advanced revolves around the need to re-politicize this discourse and policy prescriptions. Empirically, my discussion is based on the ‘political activist work’ carried out by the regional migrant rights network in Asia, the Migrant Forum in Asia (MFA).
AN IRRIGATED EMPIRE: THE VIEW FROM OTTOMAN FAYYUM
Authors: Mikhail Alan
Published: October 2010

Using both Ottoman Turkish and Arabic archival materials, this article narrates the history of irrigation in Fayyum during the first half of the 18th century. Its environmental perspective shows how a shared reliance on natural resource management bound together extremely rural regions of the Ottoman Empire like Fayyum with centers of power in Istanbul and Cairo. It seeks to make two historiographical interventions. First, its focus on irrigation reveals how the center–periphery model of early modern empires fails to capture the complexity of relationships that rural regions of the Ottoman Empire maintained with other provinces and towns both in the empire and beyond. Water in Fayyum grew food that forged connections of commodity movement with areas of the Mediterranean and Red Seas. Second, through an examination of such intraimperial and transregional ties, this article argues that Egyptian peasants held much of the power in these relationships.
THE ROLE OF SECTARIANISM IN THE ALLOCATION OF PUBLIC EXPENDITURE IN POSTWAR LEBANON
Authors: Salti Nisreen , Chaaban Jad
Published: October 2010

The purpose of this article is twofold. First, we aim to evaluate the records of executive branches of the Lebanese government that are involved in public social spending in terms of their ability to respond to need. Second, we attempt to uncover the criteria underlying the distribution of public social spending. The allocation of funds across sectors and administrative districts is evaluated according to a vector of the socioeconomic characteristics of each locality thought to be of relevance. We find that the association between need and spending is, at best, very loose. When we use the geographical distribution of spending and voting data from each locality to estimate each religious sect's share of public spending, we find a striking conformity between the sectarian composition of the population and each sect's estimated share of national public spending. The logic of the disbursement of public funds and the mechanism underlying the observed one-man one-dollar distribution rule—a rule with primacy over health, education, and infrastructure needs as well as imbalances across regions—is that distribution be balanced across sects.
The Effectiveness of Monetary Policy Anchors: Firm-Level Evidence
Authors: Broz J. Lawrence , Plouffe Michael
Published: October 2010

Analyses of monetary policy posit that exchange-rate pegs, inflation targets, and central bank independence can help anchor private-sector inflation expectations. Yet there are few direct tests of this argument. We offer cross-national, micro-level evidence on the effectiveness of monetary anchors in controlling private-sector inflation concerns. Using firm-level data from eighty-one countries (approximately 10,000 firms), we find evidence that “international” anchors (exchange-rate commitments) correlate significantly with a substantial reduction in private-sector concerns about inflation while “domestic” anchors (inflation targeting and central bank independence) do not. Our conjecture is that private-sector inflation expectations are more responsive to exchange-rate anchors because they are more transparent, more constraining, and more costly than domestic anchoring arrangements.
Oil and Revolutionary Governments: Fuel for International Conflict
Authors: Colgan Jeff D.
Published: October 2010

Oil-exporting states, or petrostates, engage in militarized interstate disputes (MIDs) at a much higher rate on average than nonpetrostates. Why is this so? Further, what explains the variation among the petrostates in adopting aggressive foreign policies and engaging in MIDs on that basis? This article develops a theory that proposes that revolutionary petrostates have a higher propensity to launch MIDs than comparable nonpetrostates. This theory is tested with statistical analysis using a new quantitative data set that identifies revolutionary governments in the period 1945–2001. The results show that petro-revolutionary governments constitute a special threat to international peace and security. This evidence of resource-backed aggression challenges the conventional view of petrostates as the targets of international competition for resources.
FERTILITY AMONG HIV-INFECTED INDIAN WOMEN: THE BIOLOGICAL EFFECT AND ITS IMPLICATIONS
Authors: DARAK SHRINIVAS , JANSSEN FANNY , HUTTER INGE
Published: October 2010

In India, nearly one million women of childbearing age are infected with HIV. This study sought to examine the biological effect of HIV on the fertility of HIV-infected Indian women. This is relevant for the provision of pregnancy-related counselling and care to the infected women, and for estimating the HIV prevalence among women and children. The study used retrospectively collected data from the National Family Health Survey (2005–2006) and applied a matched case control study design to compare the effect of HIV on conception, pregnancy rates and pregnancy outcomes among HIV-infected (N=69) and HIV-non-infected (N=345) women, both unaware of their HIV status. Pregnancy rates and pregnancy outcomes were compared through non-parametric statistical tests, whereas the effect of HIV on fecundity was studied by analysing the interval between last two pregnancies using Cox regression. The pregnancy rate was observed to be lower among HIV-infected than HIV-non-infected women (RR=0.77). The difference, however, was not statistically significant (p=0.064). There was also no statistically significant difference in the interval between last two pregnancies (p=0.898). Significantly higher number of pregnancies among HIV-infected women resulted in termination because of miscarriage or stillbirths (p=0.004). Therefore, while providing clinical care and counselling to infected women, the possibility of adverse pregnancy outcomes should be considered. Due to the higher rate of adverse pregnancy outcomes, attendance of HIV-infected women at antenatal clinics might be greater, which could lead to overestimation of HIV prevalence derived from antenatal care surveillance sites.
Drag and lift forces on a counter-rotating cylinder in rotating flow
Authors: SUN CHAO , MULLIN TOM , VAN WIJNGAARDEN LEEN , LOHSE DETLEF
Published: October 2010

Results are reported of an experimental investigation into the motion of a heavy cylinder free to move inside a water-filled drum rotating around its horizontal axis. The cylinder is observed to either co-rotate or, counter-intuitively, counter-rotate with respect to the rotating drum. The flow was measured with particle image velocimetry, and it was found that the inner cylinder significantly altered the bulk flow field from the solid-body rotation found for a fluid-filled drum. In the counter-rotation case, the generated lift force allowed the cylinder to freely rotate without contact with the drum wall. Drag and lift coefficients of the freely counter-rotating cylinder were measured over a wide range of Reynolds numbers, 2500 < Re < 25000, dimensionless rotation rates, 0.0 < α < 1.2, and gap to cylinder diameter ratios 0.003 < G/2a < 0.5. Drag coefficients were consistent with previous measurements on a cylinder in a uniform flow. However, for the lift coefficient, considerably larger values were observed in the present measurements. We found the enhancement of the lift force to be mainly caused by the vicinity of the wall.
Mechanisms of flow-induced deformation of porous media
Authors: HELLSTRÖM J. G. I. , FRISHFELDS V. , LUNDSTRÖM T. S.
Published: October 2010

The study investigates creeping flow-induced alteration in the permeability of deformable particle systems. Low-Reynolds-number transversal flow through random arrays of aligned cylinders is considered by means of a combined methodology of directly solving the two-dimensional (2D) Stokes equations for the flow in the vicinity of two particles and minimising the dissipation rate in a system comprising thousands of particles. The results demonstrate that the more compact the system, the greater the possible relative change of permeability when a high flow rate is applied. The permeability of large random arrays always increases when increasing the flow rate, which is most apparent in compact systems with equal-sized particles. The permeability can sometimes decrease but only in structured or small systems.
A first-principle predictive theory for a sphere falling through sharply stratified fluid at low Reynolds number
Authors: CAMASSA ROBERTO , FALCON CLAUDIA , LIN JOYCE , McLAUGHLIN RICHARD M. , MYKINS NICHOLAS
Published: October 2010

A sphere exhibits a prolonged residence time when settling through a stable stratification of miscible fluids due to the deformation of the fluid-density field. Using a Green's function formulation, a first-principles numerically assisted theoretical model for the sphere–fluid coupled dynamics at low Reynolds number is derived. Predictions of the model, which uses no adjustable parameters, are compared with data from an experimental investigation with spheres of varying sizes and densities settling in stratified corn syrup. The velocity of the sphere as well as the deformation of the density field are tracked using time-lapse images, then compared with the theoretical predictions. A settling rate comparison with spheres in dense homogeneous fluid additionally quantifies the effect of the enhanced residence time. Analysis of our theory identifies parametric trends, which are also partially explored in the experiments, further confirming the predictive capability of the theoretical model. The limit of infinite fluid domain is considered, showing evidence that the Stokes paradox of infinite fluid volume dragged by a moving sphere can be regularized by density stratifications. Comparisons with other possible models under a hierarchy of additional simplifying assumptions are also presented.
Novel management of cervical necrotising fasciitis in a developing country: case report
Authors: Salisu A , Adeosun A A , Emma-Nzekwue N H , Abubakar S B
Published: October 2010

Objective:

We report a rare case of cervical necrotising fasciitis arising from poorly managed acute tonsillitis.

Case report:

A 23-year-old woman presented with a two-week history of fever and an eight-day history of painful neck swelling. Nine days before presentation, she had received digital manipulation of her throat by a neighbour, which had worsened her throat pain. There was associated progressive generalised neck swelling, odynophagia, dysphagia and dyspnoea. An X-ray of the neck soft tissue showed multiple gas collections.

Conclusion:

Cervical necrotising fasciitis is rare and usually odontogenic in origin. It is associated with a high mortality rate. Our patient responded to aggressive daily bedside wound debridements and dressings, appropriate intravenous antibiotics and high-protein nutritional support. In this way, exploration under general anaesthesia was avoided, in a developing country with limited facilities.
Manipulation of fractured nose using mallet and champagne cork
Authors: Rollin M , De Zoysa N , Mochloulis G
Published: October 2010

We describe an alternative method of manipulating fractured nasal bones using a surgical mallet and a champagne cork. This method enables accurate fracture reduction with minimal skin trauma, by affording the surgeon a high level of control. This method may be applied successfully to late-presenting fractures.
From Child Labor “Problem” to Human Trafficking “Crisis”: Child Advocacy and Anti-Trafficking Legislation in Ghana
Authors: Lawrance Benjamin N.
Published: October 2010

This article examines the relationship between multidimensional child advocacy campaigns and the enactment of Ghana's Human Trafficking Act (2005). I argue that while child advocacy has a rich history, the diffuse labor-oriented advocacy characteristic of the 1990s failed to articulate an achievable goal. Child labor advocacy was impotent because the diverse agencies involved adopted different positions about the permissibility of child labor. By contrast, the anti-trafficking initiatives of the early 2000s focused narrowly on legislative remedy and formulated a discourse of “crisis.” An anti-trafficking coalition built on an international regulation model that emerged from the cocoa industry. As agents of social and political change, domestic, regional, and foreign nongovernmental organizations and intergovernmental organizations played important roles in shaping debates and framing new law. The Ghanaian law, however, is of limited effectiveness because it ignores autochthonous social practices with historically rich traditions, and it enjoins a narrow, economic model for the proliferation of trafficking.
Fixing America's Broken Immigration System: Introduction
Authors: Ngai Mae M.
Published: October 2010

In January 2008, at the meeting of the American Historical Association, I had coffee with two colleagues, Gary Gerstle and George Sánchez, with whom I share an abiding interest in labor and immigration history, as well as current politics. We hatched an idea to hold a conference on immigration policy reform, which we believed would potentially be back on Congress's agenda after the new administration—we did not know at the time who would be the next president—took office. Ours certainly would not be the first conference on immigration policy. But we wanted to bring two perspectives that are not commonly aired in policy debates today: the historical perspective and the international perspective. We decided to bring together historians, social scientists, advocates, policy analysts, and journalists for a gathering in Washington, D.C., where we hoped to get the attention of those on Capitol Hill. We were fortunate that the Woodrow Wilson Center for International Studies agreed to host and cosponsor the event and that we were able to work with historian Sonya Michel, the center's new director for United States studies. Additional cosponsors included Columbia University, the University of Southern California, and Vanderbilt University.
America, Germany, Israel: Three Modes of Citizenship and Incorporation
Authors: Abraham David
Published: October 2010

In today's liberal democracies, the “social question” and the “immigration question” have become entwined as rarely before. Elites and citizens alike ask who belongs to the national political and social community of the “we” and what belonging entails in the way of rights and obligations. Under the impact of unprecedented free mobility for both capital and labor and the crises of the social welfare state, the borders and bonds of citizenship have been changing, mostly weakening. This essay takes a preliminary look at how these two questions are intertwined in the United States, Germany, and Israel.
What Can the United States Learn from Europe?
Authors: Joppke Christian
Published: October 2010

This article gives an overview of the European “immigration system,” which includes both immigration control and immigrant integration. Special attention is given to the Euro-specific division of competences between supranational and national levels, which is still evolving. Some lessons, both positive and negative, for the United States are drawn. Most importantly, there cannot be a coherent “immigration system” but only a patchwork of divided legal regimes guided by conflicting principles, with friction between them likely to be permanent.
Iraqi Unions and Their American Labor Allies
Authors: Zweig Michael
Published: October 2010

Since the start of the Iraq war in 2003, images of suicide bombings, religious violence, and general chaos have come to mind when most Americans have thought about Iraq. Counterposed are thoughts of US military efforts to separate the combatants and restore order. Whether one has supported or opposed the US actions in Iraq, the actual Iraqi people, almost all of them ordinary working people, remain remote and unknown.
The first neo-conservative: James Burnham and the origins of a movement
Authors: KAMPMARK BINOY
Published: October 2010

This article examines the origins of American neo-conservatism by assessing the contributions of one of its less known inspirations, James Burnham. In charting Burnham's political philosophies and various contemporary reactions to them, this article examines his legacy as it relates to the movement, specifically in his approach to foreign affairs and institutions. It argues that he was more a pioneer than is often acknowledged. In so doing this article also corrects misunderstandings that have arisen in critiques of neo-conservatism, suggesting that Burnham'soeuvremay offer more instructive guidance than some of his contemporaries in understanding the neo-conservative revolution in American foreign policy.
‘… This little ukulele tells the truth’: indie pop and kitsch authenticity
Authors: Dolan Emily I.
Published: October 2010

Indie pop, like rock and other independent genres more generally, has had a complicated relationship with mass culture. It both depends upon and simultaneously deconstructs notions of authenticity and truth. Independent genres have invited scholarly analysis and critique that often seek to unmask indie as ‘elite’ or to show the extent to which indie musics are, ironically, defined and shaped by consumer capitalism. Using songwriter Stephin Merritt's music and career as a case study, this essay explores the kinds of authenticities at work in indie pop. Indie pop, I argue, is a genre especially adept at generating ‘personal authenticity’. It is useful to turn to the concept of kitsch, understood here as an aesthetic and not a synonym for ‘bad’. Kitsch functions to cultivate personal attachment in the face of impersonal mass culture; it is this aesthetic, I argue, that indie pop has cultivated through its lo-fi and often nostalgic sound world and through its dissemination, which has relied upon dedicated collectors. The ‘honesty’ of this music does not arise from an illusion of unmediated communication, but instead from the emphasis on the process of mediation, which stresses the materiality of the music and the actual experience of listening.
‘How do you know he's not playing Pac-Man while he's supposed to be DJing?’: technology, formats and the digital future of DJ culture
Authors: Montano Ed
Published: October 2010

In light of the growing literature on DJ culture, this article explores how technological change is having a significant impact on specific areas of music production and distribution within contemporary electronic dance music culture. An ethnographic methodology is employed, based around research conducted in the Sydney dance music scene between 2002 and 2007. The aim of the article is to reveal some of the discourses and reactions in DJ practice that result from shifts in technology. With the increasing use of CDs, mp3s and computer programs such as Ableton Live, the notion that vinyl and turntables represent the authentic technology of DJ culture seems somewhat redundant. The physical movement required to mix vinyl records has meant that the associated skills of DJing have become bound up in notions of physical and visible manipulation of technology, and so the use of technology that does not require and afford such physical expression has raised questions around the fundamental skills of DJing. As such, it would seem that there needs to be a redefinition of the concept of DJing, and a reframing of the skills and abilities seen as being essential to DJ practice.
Trajectory planning for a 1-DOF clutched robotic arm
Authors: Gu Hao , Ceccarelli Marco
Published: October 2010

In this paper, we have reported a trajectory planning for a 1-degree-of-freedom clutched robotic arm. This novel robotic arm has only one actuator, but it can work in a spatial space by using a proper clutch system and a suitable trajectory planning. An algorithm has been proposed for generating a prescribed trajectory by means of seven operation modes, which are generated by different states of clutches.
Design and operation of a tripod walking robot via dynamics simulation
Authors: Liang Conghui , Gu Hao , Ceccarelli Marco , Carbone Giuseppe
Published: October 2010

A mechanical design and dynamics walking simulation of a novel tripod walking robot are presented in this paper. The tripod walking robot consists of three 1-degree-of-freedom (DOF) Chebyshev–Pantograph leg mechanisms with linkage architecture. A balancing mechanism is mounted on the body of the tripod walking robot to adjust its center of gravity (COG) during walking for balancing purpose. A statically stable tripod walking gait is performed by synchronizing the motions of the three leg mechanisms and the balancing mechanism. A three-dimensional model has been elaborated in SolidWorks® engineering software environment for a characterization of a feasible mechanical design. Dynamics simulation has been carried out in the MSC.ADAMS® environment with the aim to characterize and to evaluate the dynamic walking performances of the proposed design with low-cost easy-operation features. Simulation results show that the proposed tripod walking robot with proper input torques, gives limited reaction forces at the linkage joints, and a practical feasible walking ability on a flatten ground.
From the gut to the peripheral tissues: the multiple effects of butyrate
Authors: Guilloteau P. , Martin L. , Eeckhaut V. , Ducatelle R. , Zabielski R. , Van Immerseel F.
Published: October 2010

Butyrate is a natural substance present in biological liquids and tissues. The present paper aims to give an update on the biological role of butyrate in mammals, when it is naturally produced by the gastrointestinal microbiota or orally ingested as a feed additive. Recent data concerning butyrate production delivery as well as absorption by the colonocytes are reported. Butyrate cannot be detected in the peripheral blood, which indicates fast metabolism in the gut wall and/or in the liver. In physiological conditions, the increase in performance in animals could be explained by the increased nutrient digestibility, the stimulation of the digestive enzyme secretions, a modification of intestinal luminal microbiota and an improvement of the epithelial integrity and defence systems. In the digestive tract, butyrate can act directly (upper gastrointestinal tract or hindgut) or indirectly (small intestine) on tissue development and repair. Direct trophic effects have been demonstrated mainly by cell proliferation studies, indicating a faster renewal of necrotic areas. Indirect actions of butyrate are believed to involve the hormono–neuro–immuno system. Butyrate has also been implicated in down-regulation of bacteria virulence, both by direct effects on virulence gene expression and by acting on cell proliferation of the host cells. In animal production, butyrate is a helpful feed additive, especially when ingested soon after birth, as it enhances performance and controls gut health disorders caused by bacterial pathogens. Such effects could be considered for new applications in human nutrition.
Definitions and markers of frailty: a systematic review of literature
Authors: Borges LL , Menezes RL
Published: October 2010

Frailty is a central concept in geriatric medicine, but without a clear definition. Many regard it as a syndrome with its own clinical manifestations and pathophysiology, whilst others consider it to be the result of the accumulation of age-related deficits that predict adverse changes in health. We analysed, through a systematic review, the definitions and markers of the frailty syndrome. Twenty-five articles were included and divided, according to design, into observational, intervention, review and qualitative studies. There was a predominance of operational definitions that used only physical markers to identify frailty. The only qualitative study found that health professionals chose a multidimensional definition that took into account factors other than just the physical. We conclude that there is still no standard definition or agreement about markers of the frailty syndrome.
A NEW SPECIES OF ROELLA (CAMPANULACEAE) FROM WESTERN CAPE, SOUTH AFRICA
Authors: Cupido C. N.
Published: October 2010

A new species, Roella uncinata Cupido (Campanulaceae), from Western Cape, South Africa, is described and illustrated, and its known distribution mapped. A proposed conservation assessment is provided, and its diagnostic characters and affinity are discussed.
A REVISION OF CAUTLEYA (ZINGIBERACEAE)
Authors: Auvray G. , Newman M. F.
Published: October 2010

Cautleya (Royle ex Benth.) Hook.f. (Zingiberaceae) is revised. Two species are recognised, one of them with two varieties. They are found in northern India, Nepal, Bhutan, southern China, Burma, Thailand and Vietnam. A key is given and all taxa are described. Preliminary conservation assessments are made.
Southeastern institutional change and biological variation: evidence from the 19th century Tennessee State Prison
Authors: CARSON SCOTT ALAN
Published: October 2010

The use of height data to measure living standards is now a well-established method in economics, and a number of core findings in the literature are widely agreed upon. There are still some populations, places, and times, however, for which anthropometric evidence remains thin. This paper introduces a new dataset from the Tennessee State Prison to track the heights of comparable black and white males born between 1820 and 1906. Shorter statures were associated with close proximity to the Mississippi River, and the largest share of the white–black stature gap was associated with nativity. Black and white statures declined throughout the 19th century, and farmers were taller than non-farmers.
Prävention von Lese-Rechtschreibstörungen
Authors: Hatz Hubertus , Sachse Steffi
Published: October 2010

Zusammenfassung. Die Bedeutung der phonologischen Bewusstheit für das Erlernen von Lesen und Schreiben wurde in zahlreichen Studien herausgestellt und vorschulische Trainings haben sich als erfolgreich für die Prävention von Lese-Rechtschreibstörungen erwiesen. Die vorliegende Studie untersucht, ob bei Risikokindern in der ersten Klasse ein altersangepasstes Training der phonologischen Bewusstheit allein oder in Kombination mit einem Rechtschreibtraining den Schriftspracherwerb positiv beeinflussen und die Häufigkeit von Lese-Rechtschreibstörungen verringern kann. Eine Überlegenheit einer Gruppe mit phonologischem Training konnte weder in Bezug auf phonologische Bewusstheit noch für Leistungen im Lesen und Schreiben gezeigt werden. Das zusätzliche Rechtschreibtraining entfaltete einen kurzfristigen Effekt mit einem deutlich geringeren Anteil an Kindern mit unterdurchschnittlicher Rechtschreibleistung am Ende der ersten Klasse. Am Ende der zweiten Klasse jedoch hatte sich der Anteil an Kindern mit einer Lese-Rechtschreibstörung nicht bedeutend reduziert. Für die schulische Prävention von Lese-Rechtschreibstörungen sollte demnach frühzeitig eine intensive Förderung der Rechtschreibung integriert und längerfristig aufrechterhalten werden.
Sagen Wahrnehmungsleistungen zu Beginn der Schulzeit den Lese-Rechtschreiberfolg in Klasse 1 und 2 voraus?
Authors: Steinbrink Claudia , Schwanda Simone , Klatte Maria , Lachmann Thomas
Published: October 2010

Zusammenfassung. Die Studie überprüft die Validität der Differenzierungsproben (DP) 1 und 2 ( Breuer & Weuffen, 2006 ) bezüglich der Vorhersage von Lese-Rechtschreibschwierigkeiten am Ende von Klasse 1 und 2. Kinder mit deutscher Muttersprache wurden zu Beginn von Klasse 1 mit der DP 1 und in der Mitte von Klasse 1 mit der DP 2 getestet. Die Leistungen in den DP klären zwischen 3 und 9% der Varianz im späteren Lesen und Schreiben auf. Bei Einbeziehung zusätzlicher Prädiktoren erhöht sich die aufgeklärte Varianz. Es setzen sich aber andere Variablen, insbesondere IQ und vorschulische Lese-Rechtschreibfähigkeit als wichtigere Prädiktoren durch. Die klassifikatorischen Güteindizes Prädiktortrefferquote, Sensitivität und RATZ-Index liegen überwiegend im inakzeptablen Bereich. Somit ist die prognostische Validität von DP 1 und DP 2 als unzureichend zu bewerten. Die im Vergleich zu anderen Screeningverfahren geringere Validität wird auch im Zusammenhang mit Unterschieden hinsichtlich des Einschlusses von Kindern mit nicht-deutscher Muttersprache diskutiert.
Propagation of Jovian electron jets in heliospheric flux tube structures
Authors: Dunzlaff P. , Kopp A. , Heber B.
Published: October 2010

We discuss the propagation of magnetic flux tubes of solar origin through the heliosphere up to the orbit of Jupiter and the possibility that Jovian electron jets result from the interaction of these flux tubes with the magnetosphere of Jupiter. In order to do so, we analyze Ulysses observations in the interplanetary medium along the spacecraft's highly inclined orbit between the orbits of Earth and Jupiter. We apply a method originally developed for the analysis of ACE measurements at 1 AU, in which it was shown that the distribution of the relative change in plasma quantities can actually be attributed to plasma turbulence on the one hand and the existence of individual flux tubes in the solar wind on the other hand. The application to Ulysses data shows that this typical behavior can be observed even up to the orbit of Jupiter. In a first step, we discuss possible consequences of the existence of these flux tubes at such large distances for the transport of charged particles through the inner heliosphere. In a second step, we analyze observations of so‐called Jovian electron jets with Ulysses and Pioneer 10 data with regard to changes in the magnetic field and interpret these as the result of the magnetic interaction of flux tubes with the Jovian magnetosphere.
Low export flux of particulate organic carbon in the central Arctic Ocean as revealed by 234Th:238U disequilibrium
Authors: Cai P. , Rutgers van der Loeff M. , Stimac I. , Nöthig E.‐M. , Lepore K. , Moran S. B.
Published: October 2010

The loss of Arctic sea ice has accelerated in recent years. With the decline in sea ice cover, the Arctic Ocean biogeochemistry is undergoing unprecedented change. A key question about the changing Arctic Ocean biogeochemistry is concerning the impact of the shrinking sea ice cover on the particulate organic carbon (POC) export from the upper Arctic Ocean. Thus far, there are still very few direct measurements of POC export in the permanently ice‐covered central Arctic Ocean. A further issue is that the magnitude of the POC export so far documented in this region remains controversial. During the ARK‐XXII/2 expedition to the Arctic Ocean from 28 July to 7 October in 2007, we conducted a high‐resolution study of POC export using 234Th/238U disequilibrium. Depth profiles of total 234Th in the upper 200 m were collected at 36 stations in the central Arctic Ocean and its adjacent seas, i.e., the Barents Sea, the Kara Sea and the Laptev Sea. Samples were processed using a small‐volume MnO2 coprecipitation method with addition of a yield tracer, which resulted in one of the most precise 234Th data sets ever collected. Thorium‐234 deficit with respect to 238U was found to be evident throughout the upper 100 m over the Arctic shelves. In comparison, 234Th deficit was confined to the upper 25 m in the central Arctic Ocean. Below 25 m, secular equilibrium was approached between 234Th and 238U. The observed 234Th deficit was generally associated with enhanced total chlorophyll concentrations, indicating that in situ production and export of biogenic particles are the main mechanism for 234Th removal in the Arctic Ocean. Thorium‐234‐derived POC fluxes were determined with a steady state model and pump‐normalized POC/234Th ratios on total suspended particles collected at 100 m. Results showed enhanced POC export over the Arctic shelves. On average, POC export fluxes over the various Arctic shelves were 2.7 ± 1.7 mmol m−2 d−1 (the Barents Sea), 0.5 ± 0.8 mmol m−2 d−1 (the Kara Sea), and 2.9 ± 1.8 mmol m−2 d−1 (the Laptev Sea) respectively. In comparison, the central Arctic Ocean was characterized by the lowest POC export flux ever reported, 0.2 ± 1.0 mmol m−2 d−1 (1 standard deviation, n = 26). This value is very low compared to prior estimates and is also much lower than the POC export fluxes reported in other oligotrophic oceans. A ThE ratio (234Th‐derived POC export/primary production) of <6% in the central Arctic Ocean was estimated using the historical measurements of primary production. The low ThE ratio indicates that like other oligotrophic regimes, the central Arctic Ocean is characterized by low POC export relative to primary production, i.e., a tightly coupled food web. Our study strongly suggests that the current role of the central Arctic Ocean in C sequestration is still very limited. Meanwhile, this role might be altered because of global warming and future decline in sea ice cover.
Mixing by low‐ and high‐resolution surface geostrophic currents
Authors: Beron‐Vera F. J.
Published: October 2010

The nature of mixing near the ocean's surface is investigated by considering passive tracer advection by currents derived geostrophically using sea surface height fields that differ in their spatiotemporal resolution. One is a low‐resolution field that can be thought of as being derived using current‐generation groundtrack altimetric measurements. The other is a high‐resolution field that may be envisioned as derived using hypothetical next‐generation wideswath altimetric measurements. The investigation is carried out in two world ocean regions with quite distinct characteristics and which have been the focus of recent studies on mixing by altimetry‐derived currents. One region corresponds to an ample domain in the South Atlantic, which is traversed by vortices shed from the Agulhas current. The other region corresponds to a portion of the Pacific sector of the Southern Ocean, which is dominated by multiple zonal jets associated with the Antarctic Circumpolar Current. It is argued that while altimetry‐derived currents capture the most salient characteristics of surface ocean mixing, deterministic Lagrangian calculations may be improved by considering surface geostrophic currents with greater spatiotemporal resolution. This is supported on analysis of probability distribution functions of finite‐time Lyapunov exponents (FTLEs); inspection of Lagrangian coherent structures (or LCSs), which constitute distinguished material fluid curves that organize mixing; computation of kinetic energy and FTLE variance spectra; and realization of explicit passive tracer advection experiments.
Dicarboxylic acids, ketocarboxylic acids, α‐dicarbonyls, fatty acids, and benzoic acid in urban aerosols collected during the 2006 Campaign of Air Quality Research in Beijing (CAREBeijing‐2006)
Authors: Ho K. F. , Lee S. C. , Ho Steven Sai Hang , Kawamura Kimitaka , Tachibana Eri , Cheng Y. , Zhu Tong
Published: October 2010

Ground‐based studies of PM2.5 were conducted for determination of 30 water‐soluble organic species, including dicarboxylic acids, ketocarboxylic acids and dicarbonyls, nine fatty acids, and benzoic acid, during the Campaign of Air Quality Research in Beijing 2006 (CAREBeijing‐2006; 21 August to 4 September 2006) at urban (Peking University, PKU) and suburban (Yufa) sites of Beijing. Molecular distributions of dicarboxylic acids demonstrated that oxalic acid (C2) was the most abundant species, followed by phthalic acid (Ph) and succinic acid (C4) at both sites. The sum of three dicarboxylic acids accounted for 71% and 74% of total quantified water‐soluble organics (327–1552 and 329–1124 ng m−3) in PKU and Yufa, respectively. Positive correlation was found between total quantified water‐soluble species and water‐soluble organic compounds (WSOC). On a carbon basis, total quantified dicarboxylic acids and ketocarboxylic acids and dicarbonyls account for up to 14.2% and 30.4% of the WSOC in PKU and Yufa, respectively, suggesting that they are the major WSOC fractions in Beijing. The distributions of fatty acids are characterized by a strong even carbon number predominance with maximum at hexadecanoic acid (C16:0). The ratio of octadecanoic acid (C18:0) to hexadecanoic acid (C16:0) (0.39–0.85, with an average of 0.36) suggests that in addition to vehicular emissions, an input from cooking emissions is important, as is biogenic emission. Benzoic acid that has been proposed as a primary pollutant from vehicular exhaust and a secondary product from photochemical reactions was found to be abundant: 72.2 ± 58.1 ng m−3 in PKU and 78.0 ± 47.3 ng m−3 in Yufa. According to the 72 hour back trajectory analysis, when the air mass passed over the southern or southeastern part of Beijing (24–25 August and 1–2 September), the highest concentrations of organic compounds were observed. On the contrary, when the clean air masses came straight from the north during 3–4 September, the lowest levels of organic compounds were recorded. This study demonstrates that pollution episodes in Beijing were strongly controlled by wind direction; that is, air quality in Beijing is good when air masses originate from the north and northwest, whereas it deteriorates when the air mass originates from the south and southeast.
Detection and mapping of hydrocarbon deposits on Titan
Authors: Clark Roger N. , Curchin John M. , Barnes Jason W. , Jaumann Ralf , Soderblom Larry , Cruikshank Dale P. , Brown Robert H. , Rodriguez Sébastien , Lunine Jonathan , Stephan Katrin , Hoefen Todd M. , Le Mouélic Stéphane , Sotin Christophe , Baines Kevin H. , Buratti Bonnie J. , Nicholson Philip D.
Published: October 2010

We report the identification of compounds on Titan's surface by spatially resolved imaging spectroscopy methods through Titan's atmosphere, and set upper limits to other organic compounds. We present evidence for surface deposits of solid benzene (C6H6), solid and/or liquid ethane (C2H6), or methane (CH4), and clouds of hydrogen cyanide (HCN) aerosols using diagnostic spectral features in data from the Cassini Visual and Infrared Mapping Spectrometer (VIMS). Cyanoacetylene (2‐propynenitrile, IUPAC nomenclature, HC3N) is indicated in spectra of some bright regions, but the spectral resolution of VIMS is insufficient to make a unique identification although it is a closer match to the feature previously attributed to CO2. We identify benzene, an aromatic hydrocarbon, in larger abundances than expected by some models. Acetylene (C2H2), expected to be more abundant on Titan according to some models than benzene, is not detected. Solid acetonitrile (CH3CN) or other nitriles might be candidates for matching other spectral features in some Titan spectra. An as yet unidentified absorption at 5.01‐μm indicates that yet another compound exists on Titan's surface. We place upper limits for liquid methane and ethane in some locations on Titan and find local areas consistent with millimeter path lengths. Except for potential lakes in the southern and northern polar regions, most of Titan appears “dry.” Finally, we find there is little evidence for exposed water ice on the surface. Water ice, if present, must be covered with organic compounds to the depth probed by 1–5‐μm photons: a few millimeters to centimeters.
Upper limits on Titan's magnetic moment and implications for its interior
Authors: Wei H. Y. , Russell C. T. , Dougherty M. K. , Neubauer F. M. , Ma Y. J.
Published: October 2010

Measurements from the Cassini spacecraft reveal a largely magnetized ionosphere of Titan whose low‐altitude fields could be from the interior of Titan or from penetrating external fields. We use the Cassini magnetic field measurements obtained during 25 Titan flybys to examine the upper limit of Titan's internal magnetic moment. The radial component of the magnetic field near the Titan surface (from 950 to 1100 km) is used to calculate the permanent dipole moment. The calculated upper limit of the permanent dipole moment is 0.78 nT × RTi3, that is, for the z, y, and x directions (0.46, 0.55, 0.29, respectively) nT × RTi3, with an error of ∼0.5 nT in each component. This value is not significantly different from zero, but it is also a factor of 5 lower than the previous upper limit from Voyager observations. This small (possibly zero) magnetic moment of Titan indicates that the interior of the moon does not support a magnetic dynamo, in agreement with the results of recent gravity study which suggest an incompletely differentiated interior. The induced moment of Titan is examined to test the existence of a subsurface ocean in Titan. The data obtained thus far are not sufficient to provide definitive evidence of the existence and depth of a subsurface ocean. This situation will be improved with the addition of measurements after Saturn's equinox when the external inducing field changes significantly.
Quantifying ultrafine pedogenic magnetic particles in Chinese loess by monitoring viscous decay of superparamagnetism
Authors: Wang Xisheng , Løvlie Reidar , Zhao Xiangyu , Yang Zhenyu , Jiang Fuchu , Wang Shubing
Published: October 2010

We propose a new approach for quantifying pedogenically produced ultrafine (nanometer‐scale) magnetic particles in Chinese loess. We have recorded the viscous decay (Δt = 100 s) of imposed isothermal remanent magnetization (IRM) assumed to be selectively carried by superparamagnetic particles (Jv). Application of viscosity measurements (relaxometry) to loess‐paleosol sequences from the SE extremity of the Chinese Loess Plateau reveals that Jv aptly reflects contributions of viscous superparamagnetic (SP) particles to the total remanence carried by an assemblage of magnetic particles. Time decay of Jv can be determined with a higher resolution than the conventionally used frequency‐dependent susceptibility (χfd%) for characterizing the relative abundance of SP particles. The nearly logarithmic time decay of IRM implies a rather broad grain size distribution of pedogenic particles in Chinese loess that may range from a lower size limit of ∼10 nm to an upper limit of ∼40 nm with a prevalent grain size maximum of ∼21–25 nm. Numerical calculations of the time dependence of IRM decay demonstrate that the actual contribution of fine‐grained pedogenic magnetite/maghemite to the total remanence is at least twice as large as that estimated by both χfd% and our proposed Jv% parameter. We therefore propose that determination of superparamagnetic contributions by the time dependence of IRM viscosity is a useful technique for tracking pedogenic processes and hence paleoclimatic conditions of Chinese loess.
Dynamics and rapid migration of the energetic 2008–2009 Yellowstone Lake earthquake swarm
Authors: Farrell Jamie , Smith Robert B. , Taira Taka'aki , Chang Wu‐Lung , Puskas Christine M.
Published: October 2010

Yellowstone National Park experienced an unusual earthquake swarm in December–January, 2008–2009 that included rapid northward migration of the activity at 1 km per day and shallowing of the maximum focal depths from 12 to 2 km beneath northern Yellowstone Lake. The swarm consisted of 811 earthquakes, 0.5 <MW< 4.1, aligned on a N–S 12‐km‐long vertical plane of hypocenters. The largest earthquake of the swarm had a 50% tensile crack‐opening source determined by a full waveform inversion that we interpret as a magmatic expansion component. In addition, GPS data revealed E–W crustal extension coincident with the swarm. Modeling of GPS and seismic data is consistent with E–W opening of ∼10 cm on a N–S striking vertical dike. Our interpretation is that the swarm was induced by magmatic fluid migration or propagation of a poroelastic stress pulse along a pre‐existing fracture zone.
The slab ocean El Niño
Authors: Dommenget Dietmar
Published: October 2010

In a series of Atmospheric model simulations coupled to a simple slab ocean model it is illustrated that El Niño type of SST variability can exist in the absence of any ocean dynamics. Atmospheric feedbacks in cloud cover and changes in the wind field can produce positive and delayed negative feedbacks that together with the heat capacity of the upper ocean can produce a damped interannual oscillation in the equatorial Pacific that is comparable in strength and has characteristics to the observed phenomenon. The evolution of the SST pattern is similar to the SST‐mode of El Niño, but is entirely controlled by atmospheric feedbacks. The results challenge and extend our current understanding of the feedback mechanisms of El Niño in climate models and may also highlight possible atmospheric mechanisms that could partly control some observed ENSO events.