bluuebunny/crossref_metadata_2025 huggingface dataset:
Can methylene amidogene and its isomers be formed by a concerted reaction?
Authors: Metropoulos Aristophanes
Published: November 2009

We have explored the possibility of occurrence of the concerted formation of the methylene amidogene radical and its cis isomer from H2 and CN at energy regimes of over 60 kcal/mol relative to the ground state of the radical. We have concluded that for the cases of parallel and perpendicular orientations of H2 and CN, a concerted reaction is possible in principle provided that H2 is vibrationally excited. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Bond percolation with attenuation in high dimensional Voronoĭ tilings
Authors: Balister Paul , Bollobás Béla
Published: November 2009

Let $\cal{P}$ be the set of points in a realization of a uniform Poisson process in ℝn. The set $\cal{P}$ determines a Voronoĭ tiling of ℝn. Construct an infinite graph $\cal{G}$ with vertex set $\cal{P}$ and edges joining vertices when the corresponding Voronoĭ cells share a (n − 1)‐dimensional boundary face. We consider bond percolation models on $\cal{G}$ obtained by declaring each edge xy of $\cal{G}$ open independently with probability p(∥x − y∥), depending only on the Euclidean distance ∥x − y∥ between the vertices. We give some sufficient conditions on p(t) that ensures that an infinite connected component (i.e., percolation) occurs, or does not occur. In particular, we show that for p(t) = p is a constant, there is a phase transition at a critical probability p = pc(n), where 2−n(5nlog n)−1 ≤ pc(n) ≤ C2−n $\sqrt{n}\;{\rm log} \; n$. We also show that if p(t) = e−λt then there is a phase transition at a critical parameter λ = λc(n), where λc(n) = (log e2 + o(1))n/2rn, where rn is the radius of the n‐dimensional sphere that, on average, contains a single point of $\cal{P}$. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Coloring H‐free hypergraphs
Authors: Bohman Tom , Frieze Alan , Mubayi Dhruv
Published: November 2009

Fix r ≥ 2 and a collection of r‐uniform hypergraphs $\cal{H}$. What is the minimum number of edges in an $\cal{H}$‐free r‐uniform hypergraph with chromatic number greater than k? We investigate this question for various $\cal{H}$. Our results include the following:

An (r,l)‐system is an r‐uniform hypergraph with every two edges sharing at most l vertices. For k sufficiently large, there is an (r,l)‐system with chromatic number greater than k and number of edges at most c(kr−1 log k)l/(l−1), where

This improves on the previous best bounds of Kostochka et al. (Random Structures Algorithms 19 (2001), 87–98). The upper bound is sharp apart from the constant c as shown in (Random Structures Algorithms 19 (2001) 87–98).

The minimum number of edges in an r‐uniform hypergraph with independent neighborhoods and chromatic number greater than k is of order kr+1/(r−1) log O(1)k as k → ∞. This generalizes (aside from logarithmic factors) a result of Gimbel and Thomassen (Discrete Mathematics 219 (2000), 275–277) for triangle‐free graphs.

Let T be an r‐uniform hypertree of t edges. Then every T‐free r‐uniform hypergraph has chromatic number at most 2(r − 1)(t − 1) + 1. This generalizes the well‐known fact that every T‐free graph has chromatic number at most t.

Several open problems and conjectures are also posed. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Exemplary data set sample size calculation for Wilcoxon–Mann–Whitney tests
Authors: Divine George , Kapke Alissa , Havstad Suzanne , Joseph Christine L. M.
Published: November 2009

Zhao, Rahardja and Qu consider sample size calculation for Wilcoxon–Mann–Whitney (WMW) tests for data with ties, and present a straightforward formula. We observe that the ‘exemplary data set’ approach, usually applied in more complex situations, has a close relationship to the Zhao–Rahardja–Qu method for WMW sample size estimation and they are asymptotically equivalent. Therefore, the exemplary data set approach can be used to easily obtain estimates similar to those that the closed formula gives. We illustrate application of both methods for a WMW sample size estimation example, and also extend the simulation study presented by Zhao et al. We find that the Zhao–Rahardja–Qu formula (and by extension the exemplary data set method) can give estimates just as accurate as those obtained using either the Kolassa approach (via nQuery Advisor) or the O'Brien–Castelloe approach (via SAS 9.2 PROC POWER), for 1:1 and 1:2 allocation ratios. However, the latter two methods can be more accurate for a ratio of 1:4 or 1:19. Finally, we note the general utility of the exemplary data set approach for sample size estimation, even in other situations where closed‐form sample size formulae exist. Copyright © 2009 John Wiley & Sons, Ltd.
An FGF4-FRS2α-Cdx2 Axis in Trophoblast Stem Cells Induces Bmp4 to Regulate Proper Growth of Early Mouse Embryos
Authors: Murohashi Michiko , Nakamura Takahisa , Tanaka Satoshi , Ichise Taeko , Yoshida Nobuaki , Yamamoto Tadashi , Shibuya Masabumi , Schlessinger Joseph , Gotoh Noriko
Published: November 2009

A variety of stem cells are controlled by the actions of multiple growth factors in vitro. However, it remains largely unclear how growth factors control the proliferation and differentiation of stem cells in vivo. Here, we describe a novel paracrine mechanism for regulating a stem cell niche in early mammalian embryos, which involves communication between the inner cell mass (ICM) and the trophectoderm, from which embryonic stem (ES) cells and trophoblast stem (TS) cells can be derived, respectively. It is known that ES cells produce fibroblast growth factor (FGF)4 and that TS cells produce bone morphogenetic protein (Bmp)4. We provide evidence that FRS2α mediates activation of the extracellular signal-regulated progein kinase (ERK) pathway to enhance expression of transcription factor Cdx2 in TS cells in response to FGF4. Cdx2 in turn binds to an FGF4-responsive enhancer element of the promoter region of Bmp4, leading to production and secretion of Bmp4. Moreover, exogenous Bmp4 is able to rescue the defective growth of Frs2α-null ICM. These findings suggest an important role of Cdx2 for production of Bmp4 in TS cells to promote the proper growth of early mouse embryos.
Reprogramming of Human Fibroblasts to Induced Pluripotent Stem Cells under Xeno-free Conditions
Authors: Rodríguez-Pizà Ignasi , Richaud-Patin Yvonne , Vassena Rita , González Federico , Barrero María José , Veiga Anna , Raya Angel , Belmonte Juan Carlos Izpisúa
Published: November 2009

The availability of induced pluripotent stem cells (iPSCs) has created extraordinary opportunities for modeling and perhaps treating human disease. However, all reprogramming protocols used to date involve the use of products of animal origin. Here, we set out to develop a protocol to generate and maintain human iPSC that would be entirely devoid of xenobiotics. We first developed a xeno-free cell culture media that supported the long-term propagation of human embryonic stem cells (hESCs) to a similar extent as conventional media containing animal origin products or commercially available xeno-free medium. We also derived primary cultures of human dermal fibroblasts under strict xeno-free conditions (XF-HFF), and we show that they can be used as both the cell source for iPSC generation as well as autologous feeder cells to support their growth. We also replaced other reagents of animal origin (trypsin, gelatin, matrigel) with their recombinant equivalents. Finally, we used vesicular stomatitis virus G-pseudotyped retroviral particles expressing a polycistronic construct encoding Oct4, Sox2, Klf4, and GFP to reprogram XF-HFF cells under xeno-free conditions. A total of 10 xeno-free human iPSC lines were generated, which could be continuously passaged in xeno-free conditions and maintained characteristics indistinguishable from hESCs, including colony morphology and growth behavior, expression of pluripotency-associated markers, and pluripotent differentiation ability in vitro and in teratoma assays. Overall, the results presented here demonstrate that human iPSCs can be generated and maintained under strict xeno-free conditions and provide a path to good manufacturing practice (GMP) applicability that should facilitate the clinical translation of iPSC-based therapies.
Effect of filler material on local and global behaviour of buckling‐restrained braces
Authors: Gheidi Ali , Mirtaheri Masoud , Zandi Amir Peyman , Alanjari Pejman
Published: November 2009

The nonlinear response of buildings has attracted a tremendous amount of attention in recent years. Braces, as lateral force‐resisting elements of a structure, are designed to not only react in the elastic region, but also to exhibit nonlinear response beyond the elastic limit. However, buckling in compression drastically degrades the performance of braces under earthquake loading. Buckling restrained braces (BRBs) have been evolved into very effective systems for severe seismic applications. They prevent buckling in compression through the encasing of core steel into a steel tube and confining infill concrete.

The effect of infill material is investigated in this research through the use of experimental tests. Filler material may be concrete, grout or mortar, as well as granular material such as compacted aggregate. Moreover, lightweight concrete or lean concrete may be utilized as filler to reduce the overall structural weight. Furthermore, the need for unbonding material may not arise when sand and gravel mixture is used. Nevertheless, the strength of the aggregate should be such that no buckling or strength deterioration is observed. Parametric studies on BRB characteristics are carried out in this research. Results of cyclic loading tests are then provided for individual cases to characterize the effect of response parameters of BRB assemblages. Copyright © 2009 John Wiley & Sons, Ltd.
Metal‐Rich Phosphide Lu3Ir7P5 – Flux Growth and Crystal Chemistry
Authors: Pfannenschmidt Ulrike , Rodewald Ute Ch. , Pöttgen Rainer
Published: November 2009

The metal rich phosphide Lu3Ir7P5 was synthesized from the elements in a bismuth flux (1:2:2:60 molar ratio, 1370 K, slow cooling rate). Lu3Ir7P5 crystallizes with a new structure type which was characterized by powder and single‐crystal X‐ray diffraction: Cmcm, a = 390.30(8), b = 3238.3(6), c = 1515.4(3) pm, wR2 = 0.0634, 1642 F2 values and 101 variables. The iridium and phosphorus atoms build up a complex three‐dimensional [Ir7P5]δ– polyanionic network, in which the lutetium atoms fill slightly distorted hexagonal prisms. The nine crystallographically independent iridium atoms have between three and five phosphorus neighbors in trigonal or square planar, tetrahedral, and square pyramidal coordination. All phosphorus atoms are isolated with coordination number 9 in the form of tricapped trigonal prisms. Lu3Ir7P5 belongs to the large family of metal rich phosphides with a metal:phosphorus ratio of 2:1.
Complex regional pain syndrome type I: efficacy of stellate ganglion blockade
Authors: Yucel Istemi , Demiraran Yavuz , Ozturan Kutay , Degirmenci Erdem
Published: November 2009

Background

This study was performed to evaluate the treatment of complex regional pain syndrome (CRPS) type I with stellate ganglion blockade.

Materials and methods

We performed three blockades at weekly intervals in 22 patients with CRPS type I in one hand. The patients were divided into two groups depending on the time between symptom onset and treatment initiation. Group 1and 2 patients had short and long symptom-onset-to-treatment intervals, respectively. Pain intensity, using a visual analog score (VAS), and range of motion (ROM) for the wrist joint were assessed before and 2 weeks after treatment and were compared using nonparametric statistical analysis.

Results

Treatment produced a statistically significant difference in wrist ROM for all patients (P < 0.001). VAS values showed an overall decrease from 8 ± 1 to 1 ± 1 following treatment, and there was a significant difference in VAS value between groups 1 and 2 (P < 0.05).

Conclusions

We concluded that stellate ganglion blockade successfully decreased VAS and increased ROM of wrist joints in patients with CRPS type I. Further, the duration between symptom onset and therapy initiation was a major factor affecting blockade success.
Can emergency medical services personnel identify pneumothorax on focused ultrasound examinations?
Authors: Raio Christopher C. , Modayil Veena , Cassara Michael , Dubon Mary , Patel Jagruti , Shah Trupti , Chun Penelope , Nelson Mathew , Chiricolo Gerardo , Sama Andrew E. , Liu Yiju Teresa
Published: November 2009

Background

Ultrasound is of proven accuracy in the diagnosis of pneumothorax. In certain locations, pre-hospital providers are adopting its use for the management of critically ill patients.

Objectives

To determine the sensitivity and specificity of emergency medical service (EMS) providers in identifying pneumothorax on ultrasound examinations.

Methods

This was an educational study evaluating 33 EMS providers. Each subject went through a brief didactic session covering the use of ultrasound in diagnosis of pneumothorax. They were then given an examination consisting of 20 individual ultrasound real-time video cases depicting either a pneumothorax or normal lung sliding. Sensitivities and specificities with 95% confidence intervals (95% CIs) were calculated for recognition of pneumothorax.

Results

The 33 study participants were able to identify pneumothorax with a sensitivity of 82% (95% CI 77–86%), specificity of 94% (95% CI 90–96%), positive predictive value of 93% (95% CI 89–95%), and negative predictive value of 84% (95% CI 80–87%).

Conclusions

Emergency medical service providers were able to identify pneumothorax at a relatively high rate. Real-time scanning by the study subjects might lead to even better results.
Role of vesicle tethering factors in the ER–Golgi membrane traffic
Authors: Sztul Elizabeth , Lupashin Vladimir
Published: November 2009

Tethers are a diverse group of loosely related proteins and protein complexes grouped into three families based on structural and functional similarities. A well‐accepted role for tethering factors is the initial attachment of transport carriers to acceptor membranes prior to fusion. However, accumulating evidence indicates that tethers are more than static bridges. Tethers have been shown to interact with components of the fusion machinery and with components involved in vesicle formation. Tethers belonging to the three families act at the same stage of traffic, suggesting that they mediate distinct events during vesicle tethering. Thus, multiple tether‐facilitated events are required to provide selectivity to vesicle fusion. In this review, we highlight findings that support this model.
Intraperitoneal bleeding following transvaginal oocyte retrieval
Authors: Zhen Xiumei , Qiao Jie , Ma Caihong , Fan Yanhong , Liu Ping
Published: October 2009

Objective

To investigate the risk factors for intraperitoneal bleeding following transvaginal oocyte retrieval (TVOR).

Methods

Retrospective review of records from patients who underwent TVOR between 2004 and 2008. Patients who had mild and severe intraperitoneal bleeding were compared with the same number of patients without intraperitoneal bleeding (control group) who underwent oocyte retrieval on the same day performed by the same doctor as those who experienced bleeding.

Results

Of 10251 retrieval cycles performed, 22 (0.2%) patients had intraperitoneal bleeding. Five (0.05%) patients with severe bleeding underwent laparotomy or laparoscopy, while 17 patients were managed conservatively for mild bleeding. Among patients with no bleeding, mild bleeding, or severe bleeding, there were significant differences in body mass index (P < 0.02) and number of oocytes retrieved (P < 0.01), while no differences were seen for age and pregnancy rate.

Conclusion

Patients with severe intraperitoneal bleeding had a lower body mass index, a history of surgery, were younger, and had a moderate ovarian response; those with mild bleeding were young and had a high ovarian response.
Claiming Rights across Borders: International Human Rights and Democratic Sovereignty
Authors: BENHABIB SEYLA
Published: November 2009

The status of international law and transnational legal agreements with respect to the sovereignty claims of liberal democracies has become a highly contentious theoretical and political issue. Although recent European discussions focus on global constitutionalism, there is increasing reticence on the part of many that prospects of a world constitution are neither desirable nor salutary. This article more closely considers criticisms of these legal transformations by distinguishing the nationalist from democratic sovereigntiste positions, and both, from diagnoses that see the universalization of human rights norms either as the Trojan horse of a global empire or as neocolonialist intentions to assert imperial control over the world. These critics ignore “the jurisgenerativity of law.” Although democratic sovereigntistes are wrong in minimizing how human rights norms improve democratic self-rule; global constitutionalists are also wrong in minimizing the extent to which cosmopolitan norms require local contextualization, interpretation, and vernacularization by self-governing peoples.
Variegate porphyria induces plasma and neutrophil oxidative stress: effects of dietary supplementation with vitamins E and C
Authors: Ferrer Miguel D. , Tauler Pedro , Sureda Antoni , Palacín Clara , Tur Josep A. , Pons Antoni
Published: November 2009

Our aim was to analyse the influence of variegate porphyria (VP) on the antioxidant defenses and markers of oxidative damage and inflammation in plasma and neutrophils and the effects of dietary supplementation with vitamins E and C on these parameters in plasma, neutrophils and erythrocytes. Twelve women affected by VP and twelve pair-matched healthy control women participated in a double-blind crossover study. Each participant took 50 mg/d of vitamin E and 150 mg/d of vitamin C, or a placebo, for 6 months, by consuming an almond-based beverage as the vehicle. Women affected by VP presented higher C-reactive protein and malondialdehyde (MDA) circulating levels. Plasma antioxidant defenses were not different between porphyric and control women. Neutrophils from VP women presented decreased catalase (CAT) and glutathione reductase (GR) activities together with increased protein carbonyl levels. Reactive oxygen species (ROS) production from stimulated neutrophils was also higher in porphyric women than their controls. Dietary supplementation was effective in increasing α-tocopherol levels in neutrophils and in reducing MDA levels in plasma. Erythrocyte CAT and GR activities were enhanced by the enriched beverage only in the control subjects. In conclusion, women affected by VP present a situation of inflammation, plasma oxidative damage and neutrophils more primed to the oxidative burst, with decreased antioxidant activities and increased ROS production capabilities and protein oxidative damage. Dietary supplementation with vitamin E (50 mg/d) and vitamin C (150 mg/d) for 6 months decreased plasma oxidative damage and enhanced the erythrocyte activities of CAT and GR.
Soft-part preservation in a bivalved arthropod from the Late Ordovician of Wales
Authors: PAGE ALEX , WILBY PHILIP R. , WILLIAMS MARK , VANNIER JEAN , DAVIES JEREMY R. , WATERS RICHARD A. , ZALASIEWICZ JAN A.
Published: November 2009

A new component of the Early Palaeozoic arthropod fauna is described from a monospecific accumulate of carapaces in a Late Ordovician (Katian) hemipelagic mudstone from the Cardigan district of southwest Wales (UK). Its non-biomineralized carapace is preserved as a carbonaceous residue, as is more labile anatomy (soft-parts) including the inner lamella and sub-ovate structures near its antero-dorsal margin, which we interpret to be putative eyes. The depositional context and associated fauna indicate that the arthropods inhabited an area of deep water and high primary productivity above a pronounced submarine topography. The preserved density of carapaces suggests the arthropods may have congregated into shoals or been transported post-mortem into depressions which acted as detritus traps. The accumulate provides a rare example of soft-part preservation in hemipelagic mudstones and highlights the role of organic material as a locus for authigenic mineralization during metamorphism.
Gonad morphology and gametogenesis in the deep-sea jellyfish Atolla wyvillei and Periphylla periphylla (Scyphozoa: Coronatae) collected from Cape Hatteras and the Gulf of Mexico
Authors: Lucas Cathy H. , Reed Adam J.
Published: November 2009

Observations on gonad morphology and the structure of ovaries and testes of the coronate scyphozoans Atolla wyvillei and Periphylla periphylla are described based on samples collected from the Gulf of Mexico and Cape Hatteras (north-western Atlantic). In A. wyvillei, gonads of distinguishable sex were observed in medusae as small as 17 mm bell diameter (BD). Spermatogenesis occurred within follicles (average 366 × 254 μm) that were evenly distributed throughout the gonad. Oocytes in different stages of development were observed in all the females with gonads. Oocytes arise from the gastrodermis and migrate into the mesoglea to develop from early-mid to late vitellogenic oocytes characterized by a large nucleus and granular (organic-rich) cytoplasm. The largest oocytes measured were 543 μm and 263 μm from the Gulf of Mexico and Cape Hatteras respectively. Possible reasons for this difference are discussed. In P. periphylla gonads were also initially observed in medusae 17 mm BD, although not all larger medusae had obvious gonads. Unlike A. wyvillei sperm follicles were arranged in long convoluted rows normally only one follicle thick. The organization of ooytes in female P. periphylla was very similar to A. wyvillei, although the gonads were small and the number of oocytes present in each gonad very low (<22). The largest oocyte measured was 777 μm in a 53 mm BD medusa. Although medusae were collected from one time period only (September) in this study, our findings appear to be in agreement with literature evidence indicating that coronate jellyfish produce few eggs continuously over a long time period. Aspects of gonad development and gametogenesis are discussed with respect to potential differences in site productivity and species identification.
Reappraisal ofCerithiella danielsseni(Gastropoda: Caenogastropoda: Cerithiopsidae): a taxon confined to negative temperatures in the Norwegian Sea
Authors: Høisæter Tore
Published: November 2009

Since 1993Cerithiella danielsseni(Friele, 1877) has been regarded as a variety ofC. metula(Lovén, 1846). An argument is made for reinstatingC. danielssenias a valid taxon inhabiting below-zero waters on the slope around the Nordic Seas. This conclusion is based on lack of overlap in shell morphology between specimens found below and above the ecotone where the thermocline meets the slope. Just above the ecotone and also in the Barents Sea north of ~72°N, the shelf speciesC. metulaoccurs, but with morphology slightly modified from that of the ‘typical’ form.
“DARN THAT MERRY WIDOW HAT”: THE ON- AND OFFSTAGE LIFE OF A THEATRICAL COMMODITY, CIRCA 1907–1908
Authors: Schweitzer Marlis
Published: November 2009

Decades before the rise of the international megamusical, Franz Lehár's operettaDie lustige Witwe(The Merry Widow) traveled the world, becoming a franchise surrounded by a constellation of commodities. Within two years of its opening in Vienna on 30 December 1905, the romantic tale of Hanna Glawari's second chance at love was playing in theatres across Europe and in “virtually every city in the German-speaking world,” including colonial communities in Africa and Asia. In Argentina, as many as five versions of the operetta opened simultaneously in Buenos Aires, each in a different language. By 1908, threeMerry Widowroad companies were touring the United States, and numerous burlesques of the piece were vying for the attention of theatregoers.
MEDIEVAL STAGES
Authors: Enders Jody
Published: November 2009

In 1996, R. Howard Bloch and Stephen G. Nichols edited a remarkable volume of essays calledMedievalism and the Modernist Temper, in which seventeen scholars pondered, through detailed philological analysis and imaginative cultural-studies approaches, the legacy of the Middle Ages and its relevance to modern times. “WORD'S OUT,” they began, “There's something exciting going on in medieval studies, and maybe in the Renaissance too. The study of medieval literature and culture has never been more alive or at a more interesting, innovative stage.” Bloch and Nichols understood, as few others, the pertinentcritical stagesof the interdiscipline of medieval studies. But, critically speaking, where was thestage? With the exception of Seth Lerer's terrific piece on Eric Auerbach's gender-biased editorial establishment of the text of the twelfth-centuryPlay of Adam, theatre was nowhere to be found.
UNCOVERING GEMS: THEATRICAL DESIGN COLLECTIONS AT THE WISCONSIN HISTORICAL SOCIETY
Authors: Tarantino Mary
Published: November 2009

The Wisconsin Center for Film and Theater Research (WCFTR), which is housed at the Wisconsin Historical Society in Madison, Wisconsin, and partners the historical society with the University of Wisconsin's Department of Communication Arts, was formed in 1960. It maintains a diverse collection of entertainment media, including collections of papers, audio and/or visual materials, and other creative documents such as scripts and designs. The majority of the WCFTR's collections feature film, radio, and television productions and various photographs and promotional material. The smaller theatre collections include papers related to notable actors and playwrights such as Alfred Lunt, Lynn Fontanne, Moss Hart, Langston Hughes, and George S. Kaufman; lyricists and composers such as Marc Blitzstein and Stephen Sondheim; and designers for film and theatre. This article examines the WCFTR collections of three twentieth-century theatrical designers: Wolfgang Roth, Jean Rosenthal, and Gilbert Hemsley.
Assessment of variation in seed longevity within rye, wheat and the intergeneric hybrid triticale
Authors: Niedzielski Maciej , Walters Christina , Luczak Wieslav , Hill Lisa M. , Wheeler Lana J. , Puchalski Jerzy
Published: November 2009

Seed shelf-life or longevity is difficult to predict or to measure on a practical time scale. Predictive models suggest that water has the same effect on ageing rate for all seed lots within a species and that initial seed quality is the dominating factor explaining within-species variation. These assumptions are used in ‘accelerated ageing’ or ‘controlled deterioration’ (AA/CD) tests, which are commonly used to predict seed longevity in commercial and research applications. In this study, we describe within-species variation of longevity for seeds of Secale cereale and S. strictum (cultivated rye and its wild progenitor) under typical dry storage conditions of a genebank, and show that initial seed quality is an important, but not sole, factor explaining measured longevity. We also test the correlation of seed longevity, measured under humid and dry conditions, using 50 cultivars of rye, wheat (Triticum aestivum) and the intergeneric cross triticale, to assess how well AA/CD tests predict seed shelf-life during dry storage. Known differences in longevity between wheat and rye were confirmed at all water contents, and triticale seeds demonstrated intermediate behaviour. Longevity measured for humid and dry conditions were weakly correlated when comparisons included all grain types and were not correlated in within-grain-type comparisons. Response to moisture varied among cultivars. These findings do not support assumptions made in seed ageing models that use AA/CD tests. Our results suggest that more traits are involved in the expression of seed longevity than those typically measured in studies of initial seed vigour.
Seed dormancy and germination in the Australian baobab, Adansonia gregorii F. Muell.
Authors: Turner S.R. , Dixon K.W.
Published: November 2009

Seeds of the iconic Australian baobab Adansonia gregorii display physical dormancy (PY) and germinate readily once they become water permeable, a trait found in most other species in this genus. Highest germination (100%) was observed when seeds were placed in concentrated sulphuric acid (H2SO4) for 24 h, although exposure to H2SO4 for 6–12 h also resulted in >85% germination. Exposure to boiling water for 1–5 min was far less effective in promoting germination (0–23%), although a high number of seeds were water permeable (67–99%) following boiling water treatment. However, the majority of these water-permeable seeds appeared to have been injured by boiling water exposure. Germination at warmer temperatures (30 or 35°C) was found to be optimal (81–83% germination) and proceeded rapidly, with maximum germination occurring after incubation for only 8 d. In comparison, germination at 15–25°C resulted in 3–67% germination over a longer time frame (up to 20 d). While seeds of A. gregorii display PY they are unusually sensitive to dipping in boiling water and are therefore atypical when compared to most other Adansonia species.
MODELLING SEA ICE GROWTH
Authors: MCGUINNESS MARK J.
Published: November 2009

The freezing of water to ice is a classic problem in applied mathematics, involving the solution of a diffusion equation with a moving boundary. However, when the water is salty, the transport of salt rejected by ice introduces some interesting twists to the tale. A number of analytic models for the freezing of water are briefly reviewed, ranging from the famous work by Neumann and Stefan in the 1800s, to the mushy zone models coming out of Cambridge and Oxford since the 1980s. The successes and limitations of these models, and remaining modelling issues, are considered in the case of freezing sea-water in the Arctic and Antarctic Oceans. A new, simple model which includes turbulent transport of heat and salt between ice and ocean is introduced and solved analytically, in two different cases—one where turbulence is given by a constant friction velocity, and the other where turbulence is buoyancy-driven and hence depends on ice thickness. Salt is found to play an important role, lowering interface temperatures, increasing oceanic heat flux, and slowing ice growth.
PRACTICAL RUNGE–KUTTA METHODS FOR SCIENTIFIC COMPUTATION
Authors: BUTCHER J. C.
Published: November 2009

Implicit Runge–Kutta methods have a special role in the numerical solution of stiff problems, such as those found by applying the method of lines to the partial differential equations arising in physical modelling. Of particular interest in this paper are the high-order methods based on Gaussian quadrature and the efficiently implementable singly implicit methods.
MODELLING THE GROWTH OF ZINC OXIDE NANOSTRUCTURES
Authors: MACKAY JADE R. , WHITE STEPHEN P. , HENDY SHAUN C.
Published: November 2009

Zinc oxide is known to produce a wide variety of nanostructures that show promise for a number of applications. The use of electrochemical deposition techniques for growing ZnO nanostructures can allow tight control of the morphology of ZnO through the wide range of deposition parameters available. Here we model the growth of the rods under typical electrochemical conditions, using the Nernst–Planck equations in two dimensions to predict the growth rate and morphology of the nanostructures as a function of time. Generally good quantitative and qualitative agreement is found between the model predictions and recent experimental results.
Bovine viral diarrhea virus infections in heterologous species
Authors: Passler Thomas , Walz Paul H.
Published: November 2009

Infections with Bovine viral diarrhea virus (BVDV) are not limited to cattle, but may be detected in various species in the mammalian order Artiodactyla. Despite epidemiological evidence of BVDV infections in species other than cattle, current knowledge regarding the impact of BVDV on heterologous species is incomplete. In heterologous hosts, BVDV infections with clinical signs analogous to those in cattle have been described and include disease of multiple organ systems, most notably the reproductive tract and immune system. Clinical infections may negatively impact the health and well-being of heterologous species, including camelids and captive and free-ranging wildlife. Of additional importance are BVDV infections in small ruminants and swine where difficulties arise in laboratory testing for Border disease virus (BDV) and Classical swine fever virus (CSFV), respectively. Pestiviruses are antigenically closely related and their cross-reactivity requires additional efforts in virological testing. In cattle populations, persistently infected animals are considered the main source of BVDV transmission. This phenomenon has also been detected in heterologous species, which could facilitate reservoirs for BVDV that may be of great importance where control programs are in progress. This review summarizes the current epidemiological and clinical knowledge on heterologous BVDV infections and discusses their implications.
Sind Rechenstörungen genau so häufig wie Lese-Rechtschreibstörungen?
Authors: Wyschkon Anne , Kohn Juliane , Ballaschk Katja , Esser Günter
Published: November 2009

Fragestellung: In der Literatur wird immer wieder berichtet, dass die Prävalenzraten von Lese-Rechtschreibstörungen (LRS) und Rechenstörungen vergleichbar hoch seien. Dem entgegen steht die Tatsache, dass die Korrelation zwischen Intelligenz und Lese-Rechtschreibleistungen deutlich niedriger ist als jene zwischen Intelligenz und Rechenfertigkeiten. Dies lässt bei analoger Definition der Störungen eine deutlich geringere Prävalenzrate für Rechenstörungen erwarten. Es wird untersucht, wie groß die Unterschiede zwischen verschiedenen Prävalenzschätzungen für LRS und Rechenstörungen in Abhängigkeit von den Definitionskriterien sind. Methodik: Die Fragestellung wurde unter Verwendung der Daten einer großen repräsentativen deutschen Stichprobe (N = 1970) geprüft. Ergebnisse: In Abhängigkeit von der Definition von Rechenstörungen wurden an der gleichen Stichprobe Prävalenzraten zwischen 0.1 % und 8.1 % gefunden. Bei analoger Definition von LRS und Rechenstörungen finden sich etwa zwei- bis dreimal so viele Kinder mit LRS relativ zu solchen mit Rechenstörungen. Schlussfolgerungen: Bei Vergleichen von Kindern mit LRS und Rechenstörungen müssen die Definitionskriterien analog formuliert werden.
Einschätzung kindlichen Essverhaltens durch die Eltern mit einer Kurzform der Anorectic Behaviour Observation Scale
Authors: Thiels Cornelia , Schmitz Gerdamarie S.
Published: November 2009

Fragestellung: Eignet sich die für klinische Fragestellungen entwickelte Anorectic Behavior Observation Scale (ABOS) zur Erfassung elterlicher Einschätzungen des Essverhaltens ihrer Kinder auch in epidemiologischen Feldstudien? Methodik: In einer Befragung von 1.057 SchülerInnen im Alter von 10 bis 17 Jahren füllten diese das Eating Disorder Inventory, Child Version (EDI-C) aus, die Eltern von 922 Kindern auch die ABOS. Sie besteht aus 30 Aussagen, die in drei Subskalen unterteilt sind: Auffälliges Essverhalten, Bulimieähnliches Verhalten und Hyperaktivität. Ergebnisse: Die Daten ließen psychometrische Probleme des ABOS wie Varianzeinschränkungen und extreme Verteilungen erkennen. Dies ergibt sich aus der Checklisteneigenschaft der Skala, deren Aussagen von nicht Essgestörten vorwiegend verneint werden. Mit Hilfe von explorativen und konfirmatorischen Faktorenanalysen wurden diejenigen 10 Items ausgewählt, die über bessere psychometrische Eigenschaften als der 30-Item-ABOS verfügen, ohne dass diese Auswahl zu Lasten der Validität ging. Ähnlich wie im Original heißen drei Subskalen mit 4, 2 und 4 Items Essverhalten, bulimieähnliches Verhalten und Aktivitätsniveau/Fitness. Schlussfolgerung: Die Kurzform des ABOS mit dem Namen Eating and Activity Questionnaire for Parents (EAQP) ist ein sparsames Verfahren für das Screening elterlicher Einschätzung des Essverhaltens ihrer Kinder.
Programm Zappelphilipp – Frühintervention bei delinquenten Kindern
Authors: Ristow Gerhard , Hermens Angela , Schmidt Martin H. , Holtmann Martin , Banaschewski Tobias , Poustka Luise
Published: November 2009

Fragestellung: Vorliegende Pilotstudie untersucht in Kooperation mit der Mannheimer Polizei die Wirksamkeit eines Präventionsprogramms für erstmalig delinquent gewordene Kinder mit dissozial- aggressivem und hyperkinetischem Problemverhalten. Methodik: In einer offenen Inanspruchnahme Studie wurden Kinder im Alter von 8–13 Jahren, die einmalig der Polizei durch delinquente Handlungen auffällig geworden waren; eingeschlossen. In einer ca. 4-monatigen Hometreatmentphase wurden insgesamt 24 Familien pädagogische und verhaltenstherapeutische Strategien vermittelt. Mittels DISYPS-KJ wurden vor und nach dem Training die hyperkinetisch Kernsymptomatik sowie oppositionell- aggressives und dissozial-aggressives Verhalten erfasst. Ergebnisse: Am Ende des Programms zeigte sich eine signifikante Symptomreduktion in den hyperkinetischen Subskalen sowie bei dissozial-aggressivem Verhalten. 88 % der Eltern schilderten eine deutliche Verbesserung beim Hauptproblem der Kinder. Schlussfolgerung: Vorliegendes Präventionsprogramm als indizierte Präventionsmaßnahme bei delinquenten Kindern zeigte sich nach einer ersten Beurteilung als effektiv in der Behandlung dissozial- aggressiver Auffälligkeiten.
Reduzierung selbstverletzenden und aggressiven Verhaltens durch Funktionelles Kommunikationstraining
Authors: Bienstein Pia , Nußbeck Susanne
Published: November 2009

Carr (1977 ) postulierte erstmals, dass durch die Vermittlung kommunikativer Inhalte selbstverletzendes sowie aggressives Verhalten von Menschen mit intellektueller Beeinträchtigung reduziert werden kann. Mittlerweile existiert, vornehmlich im anglo-amerikanischen Sprachraum, eine Vielzahl von Publikationen, die die Bedeutung des Funktionellen Kommunikationstrainings thematisiert. In der vorliegenden Einzelfallstudie wurde ein Preference Assessment zur Identifizierung essbarer und materieller Verstärker sowie die Experimentelle Funktionale Analyse zur Erfassung der Funktionen des selbstverletzenden und aggressiven Verhaltens durchgeführt. In einem ABAB-Design wurde die Effektivität des Funktionellen Kommunikationstrainings ermittelt. Die Ergebnisse veranschaulichen die Bedeutung funktioneller Diagnostik und die Intervention führte zur signifikanten Reduzierung des selbstverletzenden Verhaltens.
Effects of seasonal drought on net carbon dioxide exchange from a woody‐plant‐encroached semiarid grassland
Authors: Scott Russell L. , Jenerette G. Darrel , Potts Daniel L. , Huxman Travis E.
Published: November 2009

Annual precipitation in the central and southern warm‐desert region of North America is distributed climatologically between summer and winter periods with two prominent dry periods between them. We used energy and carbon dioxide (CO2) fluxes from eddy covariance along with standard meteorological and soil moisture measurements at a semiarid savanna in southern Arizona, United States, to better understand the consequences of warm or cool season drought on ecosystem CO2 exchange in these bimodally forced water‐limited regions. Over the last 100 years, this historic grassland has converted to a savanna by the encroachment of the native mesquite tree (Prosopis velutina Woot.). During each of the 4 years of observation (2004–2007), annual precipitation (P) was below average, but monsoon (July–September) P was both above and below average while cool‐season (December–March) P was always less than average by varying degrees. The ecosystem was a net source of CO2 to the atmosphere, ranging from 14 to 95 g C m−2 yr−1 with the strength of the source increasing with decreasing precipitation. When the rainfall was closest to the long‐term average in its distribution and amount, the ecosystem was essentially carbon neutral. Summer drought resulted in increased carbon losses due mainly to a shortening of the growing season and the length of time later in the season when photosynthetic gain exceeds respiration loss. Severe cool season drought led to decreased spring carbon uptake and seemingly enhanced summer respiration, resulting in conditions that led to the greatest annual net carbon loss.
Quantification of the contribution of equatorial Kelvin waves to the QBO wind reversal in the stratosphere
Authors: Ern M. , Preusse P.
Published: November 2009

Both global scale waves (e.g., Kelvin, equatorial Rossby, or Rossby‐gravity waves) and mesoscale gravity waves contribute to the wind reversals of the quasi biennial oscillation (QBO). The relative contributions of the different wave types are highly uncertain. In our work we quantify the contribution of equatorial Kelvin waves to the reversal from stratospheric easterlies to westerlies averaged over two QBO cycles in the period 2002–2006. Our analysis is based on longitude‐time spectra of temperatures measured by the SABER satellite instrument, as well as temperatures from ECMWF operational analyses. Kelvin waves of zonal wavenumber 1–6 and periods longer than 2.5 days are covered. It is found that the contribution of Kelvin waves is about 30–50% of the observed wind reversal and only 20–35% of the expected total wave forcing. The larger part of the wave forcing therefore has to be contributed by other waves, likely mesoscale gravity waves.
Cirrus clouds and deep convection in the tropics: Insights from CALIPSO and CloudSat
Authors: Sassen Kenneth , Wang Zhien , Liu Dong
Published: November 2009

Using a 2‐year data set of combined lidar and cloud radar measurements from the Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) and CloudSat satellites, the occurrence of tropical cirrus and deep convective clouds is studied. The cloud identification algorithm takes advantage of the ability of the radar to probe deep precipitating clouds and of the lidar to sample even subvisual cirrus clouds. Examined are the frequency of occurrence and the geographical distribution of these clouds, and their apparent interconnections. There is a strong apparent diurnal variability in tropical cirrus mainly over land, with significantly more cirrus detected at night compared to day, but no clear diurnal pattern in deep convective activity. CALIPSO daylight signal noise effects do not appear to be not responsible for the diurnal cirrus pattern, because high, thin tropopause transitional layer (TTL) cirrus do not show a clear diurnal effect. Stratifying the global results by estimated visible cloud optical depth τ, we find that most of the planet's subvisual (τ < ∼0.03) cirrus clouds occur in the tropics and are more frequent at night and over ocean; thin (∼0.03 < τ < ∼0.3) cirrus have their highest global frequencies over equatorial landmasses and in the west Pacific region, and are also more frequent at night but occur mainly over land; and opaque (∼0.3 < τ < ∼3.0) cirrus are spread globally and tend to occur during the day over ocean. Although it is unknown which of the several proposed cirrus cloud formation mechanisms are key in the tropics, the close association of cirrus with convective clouds implies that tropical cirrus are linked to deep convective activity, with the likely exception of TTL cirrus clouds.
Global distribution of bedrock exposures on Mars using THEMIS high‐resolution thermal inertia
Authors: Edwards C. S. , Bandfield J. L. , Christensen P. R. , Fergason R. L.
Published: November 2009

We investigate high thermal inertia surfaces using the Mars Odyssey Thermal Emission Imaging System (THEMIS) nighttime temperature images (100 m/pixel spatial sampling). For this study, we interpret any pixel in a THEMIS image with a thermal inertia over 1200 J m−2 K−1 s−1/2 as “bedrock” which represents either in situ rock exposures or rock‐dominated surfaces. Three distinct morphologies, ranked from most to least common, are associated with these high thermal inertia surfaces: (1) valley and crater walls associated with mass wasting and high surface slope angles; (2) floors of craters with diameters >25 km and containing melt or volcanics associated with larger, high‐energy impacts; and (3) intercrater surfaces with compositions significantly more mafic than the surrounding regolith. In general, bedrock instances on Mars occur as small exposures (less than several square kilometers) situated in lower‐albedo (<0.18), moderate to high thermal inertia (>350 J m−2 K−1 s−1/2), and relatively dust‐free (dust cover index <0.95) regions; however, there are instances that do not follow these generalizations. Most instances are concentrated in the southern highlands, with very few located at high latitudes (poleward of 45°N and 58°S), suggesting enhanced mechanical breakdown probably associated with permafrost. Overall, Mars has very little exposed bedrock with only 960 instances identified from 75°S to 75°N with likely <3500 km2 exposed, representing ≪1% of the total surface area. These data indicate that Mars has likely undergone large‐scale surface processing and reworking, both chemically and mechanically, either destroying or masking a majority of the bedrock exposures on the planet.
Fluorescence‐based proxies for lignin in freshwater dissolved organic matter
Authors: Hernes Peter J. , Bergamaschi Brian A. , Eckard Robert S. , Spencer Robert G. M.
Published: November 2009

Lignin phenols have proven to be powerful biomarkers in environmental studies; however, the complexity of lignin analysis limits the number of samples and thus spatial and temporal resolution in any given study. In contrast, spectrophotometric characterization of dissolved organic matter (DOM) is rapid, noninvasive, relatively inexpensive, requires small sample volumes, and can even be measured in situ to capture fine‐scale temporal and spatial detail of DOM cycling. Here we present a series of cross‐validated Partial Least Squares models that use fluorescence properties of DOM to explain up to 91% of lignin compositional and concentration variability in samples collected seasonally over 2 years in the Sacramento River/San Joaquin River Delta in California, United States. These models were subsequently used to predict lignin composition and concentration from fluorescence measurements collected during a diurnal study in the San Joaquin River. While modeled lignin composition remained largely unchanged over the diurnal cycle, changes in modeled lignin concentrations were much greater than expected and indicate that the sensitivity of fluorescence‐based proxies for lignin may prove invaluable as a tool for selecting the most informative samples for detailed lignin characterization. With adequate calibration, similar models could be used to significantly expand our ability to study sources and processing of DOM in complex surface water systems.
Soil carbon accumulation in the dry tundra: Important role played by precipitation
Authors: Klaminder Jonatan , Yoo Kyungsoo , Giesler Reiner
Published: November 2009

A positive relationship between the mean annual precipitation (MAP) and soil organic carbon (SOC) is found in most surveys covering the subarctic and boreal region. In this paper we assess mechanisms behind variable SOC pools in dry tundra soils developed along a 50 km long subarctic precipitation (snow) gradient in northern Sweden. Lead 210 is used to infer SOC accumulation rates in the O horizon. Despite an unchanged or even slightly decreasing accumulation rate of SOC in the O horizon (range 0.02–0.06 kg C m−2 yr−1) along with increasing MAP and a relative constant litter input (∼0.04 kg C m−2 yr−1), the SOC pool in the upper 1 m increase significantly with increasing MAP. This trend is mainly due to a progressively buildup of SOC in the mineral soil and argued to be the result of an accelerated vertical translocation of SOC at sites overlain by a thick snowpack. Furthermore, the loss of SOC from the O horizon through wind erosion appears to be more pronounced at snow‐poor sites. We estimate that vegetated heath soil may loose >0.02 kg C m−2 yr−1 (∼half of the annual litter fall) due to wind erosion in snow‐poor areas. We stress that lateral and vertical translocation processes inherent by precipitation regimes may be of fundamental importance for the long‐term SOC accumulation in tundra soil.