bluuebunny/crossref_metadata_2025 huggingface dataset:
Impedance matching condition analysis of the multi-filar tape-helix Blumlein PFL with discontinuous dielectrics
Authors: Zhang Y. , Liu J.L.
Published: November 2012

In this paper, the characteristic impedance matching of the inner line and outer line of the multi-filar tape-helix Blumlein pulse forming line (BPFL) is analyzed in detail by dispersion theory of tape helix. Analysis of the spatial harmonics of multi-filar tape-helix BPFL shows that the integer harmonic numbers of the excited spatial harmonics are not continuous. In addition, the basic harmonic component still dominates the dispersion characteristics of the multi-filar tape-helix BPFL at low frequency band. The impedance mismatching phenomenon caused by the discontinuity of filling dielectrics in the inner line of BPFL is studied as an important issue. Effects of dielectric discontinuity on the coupled electromagnetic fields and the parameters of the outer line are also analyzed. The impedance matching conditions are both obtained under the situations of continuous filling dielectric and discontinuous dielectrics, respectively. Impedance characteristics of these two situations are analyzed by comparison, and effects of the thickness of support dielectric on the impedance are also presented. When the 6 mm-thickness nylon support of the multi-filar tape helix is used in the filling dielectric of de-ionized water, the characteristic impedances of the inner line and outer line of BPFL are 53 Ω and 14.7 Ω, respectively. After the improvement about substituting de-ionized water by castor oil, the relative permittivities of the support dielectric and filling dielectric are almost the same, and the impedances of the inner and outer line of BPFL become 80 Ω and 79 Ω, respectively. That is to say, the impedance mismatching problem caused by dielectric discontinuity is solved. Circuit simulation and experimental results basically correspond to the theoretical results, and the fact demonstrates that impedance analysis of the multi-filar tape-helix BPFL based on dispersion theory is correct.
The “Halakhic Kernel” as a Criterion for Dating Babylonian Aggadah: Bavli Ḥullin 110a–b and Parallels
Authors: Amit Aaron
Published: November 2012

Contemporary scholarship no longer seeks to identify what was once termed “the historical kernel” of stories in the Bavli. According to scholarly consensus these longer narratives in the Bavli were formulated more or less while the Bavli as a whole was being redacted and, as Jeffrey Rubenstein has argued, reflect later Babylonian rabbinic culture. Regarding the building blocks of these stories, literary analysis at times indicates that what the historian once believed to be primitive exaggeration is in fact the earliest element of the story. With this in mind, Shamma Friedman coined the term “literary kernel” to replace the former “historical kernel.” The advantage of the term “literary kernel” is that it can be defined in a fairly objective way as the common storyline that can be identified by comparing the Bavli narrative with the story as it appears in aggadic sources in the Yerushalmi or other Palestinian traditions.
Stent therapy for acute and chronic obstructions in extracardiac Fontan conduits
Authors: Sreeram Narayanswami , Emmel Mathias , Bennink Gerardus
Published: November 2012

We describe transcatheter therapy for early onset occlusion or stenoses of extracardiac conduits in three children who had undergone Fontan completion. Successful stent implantation was associated with complete resolution of symptoms.
Mathematical Outcomes and Working Memory in Children With TBI and Orthopedic Injury
Authors: Raghubar Kimberly P. , Barnes Marcia A. , Prasad Mary , Johnson Chad P. , Ewing-Cobbs Linda
Published: November 2012

This study compared mathematical outcomes in children with predominantly moderate to severe traumatic brain injury (TBI;n= 50) or orthopedic injury (OI;n=47) at 2 and 24 months post-injury. Working memory and its contribution to math outcomes at 24 months post-injury was also examined. Participants were administered an experimental cognitive addition task and standardized measures of calculation, math fluency, and applied problems; as well as experimental measures of verbal and visual-spatial working memory. Although children with TBI did not have deficits in foundational math fact retrieval, they performed more poorly than OIs on standardized measures of math. In the TBI group, performance on standardized measures was predicted by age at injury, socioeconomic status, and the duration of impaired consciousness. Children with TBI showed impairments on verbal, but not visual working memory relative to children with OI. Verbal working memory mediated group differences on math calculations and applied problems at 24 months post-injury. Children with TBI have difficulties in mathematics, but do not have deficits in math fact retrieval, a signature deficit of math disabilities. Results are discussed with reference to models of mathematical cognition and disability and the role of working memory in math learning and performance for children with TBI. (JINS, 2013,19, 1–10)
L1–L2 convergence in clausal packaging in Japanese and English
Authors: BROWN AMANDA , GULLBERG MARIANNE
Published: November 2012

This study investigates L1–L2 convergence among bilinguals at an intermediate (CEFR-B2) level of L2 proficiency, focusing on the clausal packaging of Manner and Path of motion. Previous research has shown cross-linguistic differences between English and Japanese in this domain (Allen et al., 2003; Kita & Özyürek, 2003, though note Brown & Gullberg, 2012). We compared descriptions of motion from monolingual English and Japanese speakers to L1 and L2 descriptions from Japanese users of English as a second (ESL) and foreign (EFL) language. Results showed no significant difference between the monolinguals, who predominately used single-clause constructions packaging Manner and Path. However, bilinguals, both ESL and EFL speakers, used significantly more multi-clause constructions in both their L1 and L2. Following Pavlenko (2011a), findings are interpreted as evidence for L1–L2 convergence. We discuss potential bi-directional cross-linguistic influences underpinning the L1–L2 convergence and implications for the restructuring of bilingual systems.
Evaluation of photographs supporting an FFQ developed for adolescents
Authors: Brito Alessandra Page , Guimarães Celso Pereira , Pereira Rosangela Alves
Published: November 2012

Objective

To evaluate the validity of food photographs used to support the reporting of food intake with an FFQ designed for adolescents from Rio de Janeiro, Brazil.

Design

A set of ninety-five food photographs was elaborated. The photographs’ evaluation process included the acknowledgement of foods and portions in the pictures. In the identification of foods (ninety-five photographs) and typical portions (twelve photographs), the adolescents were requested to answer a structured questionnaire related to the food photographs. The identification of the portion size of amorphous foods (forty-three photographs) was performed using three different portion sizes of actual preparations. The proportions (and 95 % confidence intervals) of adolescents who correctly identified foods and portion size in each photograph were estimated.

Setting

A public school in Niterói, Rio de Janeiro State, Brazil.

Subjects

Sixty-two adolescents between 11·0 and 18·9 years old, randomly selected.

Results

At least 90 % of adolescents correctly identified the food in ninety-two photographs and the food in the three remaining photographs was recognized by 80–89 % of the adolescents. At least 98 % of the adolescents correctly identified eleven typical or natural portions in the food photographs. For amorphous foods, at least 70 % of teenagers correctly identified the portion size in the photograph of thirty-one foods; for the other photographs, the portion size was correctly recognized by 50–69 % of the adolescents for eight foods and by less than 50 % of adolescents for four foods.

Conclusions

The analysed photographs are appropriate visual aids to the reporting of food consumption by adolescents.
Improving myelin/oligodendrocyte-related dysfunction: a new mechanism of antipsychotics in the treatment of schizophrenia?
Authors: Ren Yuan , Wang Hanzhi , Xiao Lan
Published: November 2012

Schizophrenia is a severe psychiatric disorder with complex clinical manifestations and its aetiological factors remain unclear. During the past decade, the oligodendrocyte-related myelin dysfunction was proposed as a hypothesis for schizophrenia, supported initially by a series of neuroimaging studies and genetic evidence. Recently, the effects of antipsychotics on myelination and oligodendroglial lineage development and their underlying molecular mechanisms were evaluated. Data from those studies suggest that the antipsychotics-resulting improvement in myelin/oligodendrocyte-related dysfunction may contribute, at least in part, to their therapeutic effect on schizophrenia. Importantly, these findings may provide the basis for a new insight into the therapeutic strategy by targeting the oligodendroglia lineage cells against schizophrenia.
Personal Relevance Versus Contextual Relevance
Authors: Kim Nam Young , Sundar S. Shyam
Published: November 2012

Personalization, or the tailoring of content to meet users’ unique needs, is considered a desirable feature of digital media, particularly websites, because it results in content that is highly relevant to the user. However, it is not always possible to provide personally relevant content. Under such circumstances, the best that a system can do is provide contextually relevant peripheral content (e.g., ads) based on the topic of the main content (e.g., search-engine output). This raises an important question: Does context relevance have the same positive effects on user perceptions of websites as personal relevance? If context relevance can indeed make up for the lack of personalization, then boosting it via ad content on the site should serve to enhance appeal even when the main content is not personalized. Using a 2 × 2 factorial experiment (N = 60), we investigated whether perceptions of a website and the ads themselves varied as a function of the presence of personalized site content and ad relevance to website context. Results indicate that personal relevance and context relevance are fungible in contributing to user attitudes toward the site. Theoretical and practical implications are discussed.
Millennial scale impact on the marine biogeochemical cycle of mercury from early mining on the Iberian Peninsula
Authors: Serrano O. , Martínez‐Cortizas A. , Mateo M.A. , Biester H. , Bindler R.
Published: November 2012

The high‐resolution mercury record of a Posidonia oceanica mat in the northwest Mediterranean provides an unprecedented testimony of changes in environmental mercury (Hg) loading to the coastal marine environment over the past 4315 yr BP. The period reconstructed made it possible to establish tentative preanthropogenic background Hg levels for the area (6.8 ± 1.5 ng g–1 in bulk sediments). A small, but significant, anthropogenic Hg increase was identifiable by ~2500 yr BP, in agreement with the beginning of intense mining in Spain. Changes in the record suggest four major periods of anthropogenic Hg pollution inputs to the Mediterranean: first, during the Roman Empire (2100–1800 yr BP); second, in the Late Middle Ages (970–650 yr BP); third, in the modern historical era (530–380 yr BP); and fourth, in the industrial period (last 250 years), with Hg concentrations two‐, four‐, five‐, and tenfold higher than background concentrations, respectively. Hg from anthropogenic sources has dominated during the last millennium (increase from ~12 to ~100 ng g–1), which can be related to the widespread historical exploitation of ore resources on the Iberian Peninsula. The chronology of Hg concentrations in the mat archive, together with other Hg pollution records from the Iberian Peninsula, suggests regional‐scale Hg transport and deposition and shows earlier marine Hg pollution than elsewhere in Europe. Moreover, the mat also records a higher number of historic contamination phases, in comparison with other natural archives, probably due to the fact that the bioaccumulating capacity of P. oceanica magnify environmental changes in Hg concentrations. In this study, we demonstrate the uniqueness of P. oceanica meadows as a long‐term archive recording trends in Hg abundance in the marine coastal environment, as well as its potential role in the Mediterranean as a long‐term Hg sink.
Influence of interplanetary magnetic field and solar wind on auroral brightness in different regions
Authors: Yang Y. F. , Lu J. Y. , Wang J.‐S. , Peng Z. , Zhou L.
Published: November 2012

By integrating and averaging the auroral brightness from Polar Ultraviolet Imager auroral images, which have the whole auroral ovals, and combining the observation data of interplanetary magnetic field (IMF) and solar wind from NASA Operating Missions as a Node on the Internet (OMNI), we investigate the influence of IMF and solar wind on auroral activities, and analyze the separate roles of the solar wind dynamic pressure, density, and velocity on aurora, respectively. We statistically analyze the relations between the interplanetary conditions and the auroral brightness in dawnside, dayside, duskside, and nightside. It is found that the three components of the IMF have different effects on the auroral brightness in the different regions. Different from the nightside auroral brightness, the dawnside, dayside, and duskside auroral brightness are affected by the IMF Bx, and By components more significantly. The IMF Bx and By components have different effects on these three regional auroral brightness under the opposite polarities of the IMF Bz. As expected, the nightside aurora is mainly affected by the IMF Bz, and under southward IMF, the larger the |Bz|, the brighter the nightside aurora. The IMF Bx and By components have no visible effects. On the other hand, it is also found that the aurora is not intensified singly with the increase of the solar wind dynamic pressure: when only the dynamic pressure is high, but the solar wind velocity is not very fast, the aurora will not necessarily be intensified significantly. These results can be used to qualitatively predict the auroral activities in different regions for various interplanetary conditions.
Steep plasma depletion in dayside polar cap during a CME‐driven magnetic storm
Authors: Sakai J. , Taguchi S. , Hosokawa K. , Ogawa Y.
Published: November 2012

A series of steep plasma depletions was observed in the dayside polar cap during an interval of highly enhanced electron density on 14 October 2000 through EISCAT Svalbard Radar (ESR) field‐aligned measurements and northward‐directed low‐elevation measurements. Each depletion started with a steep dropoff to as low as 1011 m− 3 from the enhanced level of ∼3 × 1012 m−3 at F2 region altitudes, and it continued for 10–15 min before returning to the enhanced level. These depletions moved poleward at a speed consistent with the observed ion drift velocity. DMSP spacecraft observations over an extended period of time which includes the interval of these events indicate that a region of high ion densities extended into the polar cap from the equatorward side of the cusp, i.e., a tongue of ionization existed, and that the ion densities were very low on its prenoon side. Solar wind observations show that a sharp change from IMF By > 0 to By < 0 is associated with each appearance of the ESR electron density dropoff. From this unprecedented clear correlation we present a specific scenario: the series of plasma density depletions observed using the ESR is a result of the poleward drift of the undulating boundary of the tongue of ionization; this undulation is created in the cusp roughly 20 min before the ESR observation by the azimuthal intrusion, in response to the rapid prenoon shift of the footprint of the reconnection line, of the low‐density plasmas originating in the morning sector.
High‐frequency source radiation during the 2011 Tohoku‐Oki earthquake, Japan, inferred from KiK‐net strong‐motion seismograms
Authors: Kumagai Hiroyuki , Pulido Nelson , Fukuyama Eiichi , Aoi Shin
Published: November 2012

To investigate source processes of the 2011 Tohoku‐Oki earthquake, we utilized a source location method using high‐frequency (5−10 Hz) seismic amplitudes. In this method, we assumed far‐field isotropic radiation of S waves, and conducted a spatial grid search to find the best fitting source locations along the subducted slab in each successive time window. Our application of the method to the Tohoku‐Oki earthquake resulted in artifact source locations at shallow depths near the trench caused by limited station coverage and noise effects. We then assumed various source node distributions along the plate, and found that the observed seismograms were most reasonably explained when assuming deep source nodes. This result suggests that the high‐frequency seismic waves were radiated at deeper depths during the earthquake, a feature which is consistent with results obtained from teleseismic back‐projection and strong‐motion source model studies. We identified three high‐frequency subevents, and compared them with the moment‐rate function estimated from low‐frequency seismograms. Our comparison indicated that no significant moment release occurred during the first high‐frequency subevent and the largest moment‐release pulse occurred almost simultaneously with the second high‐frequency subevent. We speculated that the initial slow rupture propagated bilaterally from the hypocenter toward the land and trench. The landward subshear rupture propagation consisted of three successive high‐frequency subevents. The trenchward propagation ruptured the strong asperity and released the largest moment near the trench.
Mesenchymal stromal cells: radio‐resistant members of the bone marrow
Authors: Sugrue Tara , Lowndes Noel F , Ceredig Rhodri
Published: November 2012

Mesenchymal stromal cells (MSCs) are multi‐potent adult stem cells located in various tissues, including the bone marrow. MSCs are key components of the haematopoietic stem cell (HSC) niche within the bone marrow where they function to maintain haematopoietic homoeostasis by regulating HSC self‐renewal and function. Bone marrow exposure to ionising radiation causes rapid depletion of radio‐sensitive HSCs and their progenitors, leading to haematopoietic failure. However, host‐/patient‐derived MSCs can survive radiation doses lethal to the haematopoietic system. The mechanisms underlying MSC radio‐resistance are currently under intense investigation. Here, we review the current knowledge of MSC radio‐biology. The DNA damage response (DDR) represents an orchestrated network of signalling pathways that enable cells to respond to genotoxic damage. We discuss in detail the emerging importance of the DDR in mediating MSC radio‐resistance and examine the DDR of MSCs in the context of other stem cell types. Finally, we examine future advances in understanding MSC radio‐resistance and discuss the potential impact of the radio‐resistance of these stem cells for the clinic.
Diversity and population structure of Marine Group A bacteria in the Northeast subarctic Pacific Ocean
Authors: Allers Elke , Wright Jody J , Konwar Kishori M , Howes Charles G , Beneze Erica , Hallam Steven J , Sullivan Matthew B
Published: November 2012

Marine Group A (MGA) is a candidate phylum of Bacteria that is ubiquitous and abundant in the ocean. Despite being prevalent, the structural and functional properties of MGA populations remain poorly constrained. Here, we quantified MGA diversity and population structure in relation to nutrients and O2 concentrations in the oxygen minimum zone (OMZ) of the Northeast subarctic Pacific Ocean using a combination of catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) and 16S small subunit ribosomal RNA (16S rRNA) gene sequencing (clone libraries and 454-pyrotags). Estimates of MGA abundance as a proportion of total bacteria were similar across all three methods although estimates based on CARD-FISH were consistently lower in the OMZ (5.6%±1.9%) than estimates based on 16S rRNA gene clone libraries (11.0%±3.9%) or pyrotags (9.9%±1.8%). Five previously defined MGA subgroups were recovered in 16S rRNA gene clone libraries and five novel subgroups were defined (HF770D10, P262000D03, P41300E03, P262000N21 and A714018). Rarefaction analysis of pyrotag data indicated that the ultimate richness of MGA was very nearly sampled. Spearman’s rank analysis of MGA abundances by CARD-FISH and O2 concentrations resulted in significant correlation. Analyzed in more detail by 16S rRNA pyrotag sequencing, MGA operational taxonomic units affiliated with subgroups Arctic95A-2 and A714018 comprised 0.3–2.4% of total bacterial sequences and displayed strong correlations with decreasing O2 concentration. This study is the first comprehensive description of MGA diversity using complementary techniques. These results provide a phylogenetic framework for interpreting future studies on ecotype selection among MGA subgroups, and suggest a potentially important role for MGA in the ecology and biogeochemistry of OMZs.
Mediterranean diet- and exercise-induced improvement in age-dependent vascular activity
Authors: Klonizakis Markos , Alkhatib Ahmad , Middleton Geoff , Smith Mark F.
Published: November 2012

The aging effect on microvascular integrity, marked by endothelial dysfunction and reduction in exercise tolerance, is a major cause of CVD (cardiovascular disease). Improved dietary habits, known to reduce morbidity and mortality, are also known to attenuate those aging effects. The present study investigated the effects of combined MD (Mediterranean diet) and exercise intervention on lower- and upper-limb cutaneous microvascular functions in an older healthy population. A total of 22 sedentary healthy participants (age, 55±4 years) underwent cardiopulmonary exercise tolerance test, and were assessed for their upper- and lower-limb vascular endothelial CVC (cutaneous vascular conductance) using LDF (laser Doppler fluximetry) with endothelium-dependent [ACh (acetylcholine chloride)] and -independent [SNP (sodium nitroprusside)] vasodilation. Participants were then randomized into two groups: MD and non-MD, and followed an 8-week intervention programme, which included discontinuous treadmill running based on each individual's exertion, twice per week. Exercise training improved CVC in both groups (e.g. 0.42±0.19 compared with 1.50±1.05 and 0.47±0.26 compared with 1.15±0.59 at 1000 μCb for MD and non-MD respectively; P<0.001). This was also combined by improvement in the exercise tolerance indicated by increased VT (ventilatory threshold) in both groups [12.2±2.8 compared with 14.8±2.8 ml·(kg of body weight)−1·min−1 and 11.7±2.7 compared with 14.6±3.2 ml·(kg of body weight)−1·min−1 for MD and non-MD groups respectively; P<0.05]. However, the MD group showed greater improvement in endothelium-dependent vasodilation than non-MD [ANCOVA (analyses of co-variance), P=0.02]. The results of the present study suggest that compliance with MD, combined with regular moderate exercise, improves age-provoked microcirculatory endothelial dysfunction and increases exercise tolerance, both responsible for reducing cardiovascular risk in this age group.
Conductance enhancement due to atomic potential fluctuations in graphene
Authors: Bolmatov Dima , Zavialov D. V.
Published: November 2012

We solve the Dirac equation, which describes charge massless chiral relativistic carriers in a two-dimensional graphene. We have identified and analysed a novel pseudospin-dependent scattering effect. We compute the tunneling conductance and generalize the analytical result in the presence of the tunable atomic potential of a graphene strip. The absence of back scattering in graphene is shown to be due to Berry's phase which corresponds to a sign change of the wave function under a spin rotation of a particle. We use the transfer matrix approach and find that the electric conductance of doped graphene increases due to atomic potential fluctuations.
Ferroelectric properties of Pb(Zr,Ti)O3 films under ion-beam induced strain
Authors: Lee Jung-Kun , Nastasi Michael
Published: November 2012

The influence of an ion-beam induced biaxial stress on the ferroelectric and dielectric properties of Pb(Zr,Ti)O3 (PZT) films is investigated using the ion beam process as a novel approach to control external stress. Tensile stress is observed to decrease the polarization, permittivity, and ferroelectric fatigue resistance of the PZT films whose structure is monoclinic. However, a compressive stress increases all of them in monoclinic PZT films. The dependence of the permittivity on stress is found not to follow the phenomenological theory relating external forces to intrinsic properties of ferroelectric materials. Changes in the ferroelectric and dielectric properties indicate that the application of a biaxial stress modulates both extrinsic and intrinsic properties of PZT films. Different degrees of dielectric non-linearity suggests the density and mobility of non-180o domain walls, and the domain switching can be controlled by an applied biaxial stress and thereby influence the ferroelectric and dielectric properties.
Optimal distribution of imperfection in conductive constructal designs of arbitrary configurations
Authors: Eslami M. , Jafarpur K.
Published: November 2012

In the last decade, different conductive networks for cooling heat generating bodies have been proposed, analyzed, and optimized. Links of a highly conductive material collect the heat generated in an area and conduct it to a heat sink. The important design point is how to dedicate the limited and expensive high conductivity material to each link. Although optimizations have been performed for heat generating bodies of different shapes separately, the lack of a general method is quite obvious in the literature. Therefore, an analytical general solution for optimal distribution of highly conductive material in networks of arbitrary configuration is developed in the present article. The proposed method gives the optimum thickness of each link with a simple expression, which only depends on the geometry of heat generating bodies. Moreover, it is mathematically proved that total thermal resistance of the optimal links is a function of Bejan's parameter k̂φ and a purely geometrical function. This achievement greatly simplifies the design and optimization of any conductive cooling network. Results of the present simple formulation for configurations of various geometries are completely consistent with the available analytical and numerical solutions.
Translation and impropriety: A reading of Claude Bleton's les nègres du traducteur
Authors: Arrojo Rosemary
Published: November 2012

The hilarious plot of Claude Bleton’s novel, Les nègres du traducteur, published in France in 2004, allows us to explore the relationships that translators are often perceived to establish with their authors and originals. Bleton’s text is particularly helpful for a discussion of some notions that are usually related to contemporary theories of text and translation that revolve around the post-Nietzschean notion of the "death of the author." Aaron Janvier, Bleton’s narrator and protagonist, is a frustrated writer who manages to become a prominent translator of Spanish novels into French, and whose taste for domesticating translation strategies turns him into a powerful figure in the publishing circles of Paris, Madrid and Barcelona. As Janvier gets increasingly influential in the publishing world, he does not hesitate to turn the authors he should be translating into his "nègres," that is, into ghostwriters who are in charge of writing the "originals" that are expected to be strictly faithful to the "translations" he sends them. When some of his authors begin to reconsider their peculiar arrangement, Janvier simply kills them off. Through a close examination of Bleton’s characterization of the translator as killer, this essay proposes to rethink some recurrent clichés associated with translators, their craft, and the alleged impropriety of their close relationship with texts and authors.
The creation of shared space and the definition of a ‘light’ community in Italian television in the 1980s
Authors: Rizzo Marcella
Published: November 2012

In the mid-1970s the reform of Italy's radio and television system led to the end of RAI's monopoly and the advent of commercial television stations. This resulted in a reorganisation of the system according to the precepts of daily life and domesticity, with viewers at the centre of the relationship with the medium. This article, by analysing televisual archives such as game shows, explores how television formed part of the changes taking place in society and reveals how it became a kind of meeting-place, coinciding with the rise of an affluent society, between aspirations and desires and stereotypical models dictated by the market. These models were able to express new values that went beyond the boundaries of ideological affiliations and were in effect a response to the search for new forms of identity. In particular, television's place became an open space that was defined through modes of socialisation. It thus constructed a wider intimacy, a ‘mediatised hearth’, that progressively eroded the barriers between the private and the public sphere and led unexpectedly towards a ‘relationship of interest’ between television, competitors, viewers and financial backers. A new community then emerged, characterised more by possessing than by existing.
Local changes in lipid environment of TCR microclusters regulate membrane binding by the CD3ε cytoplasmic domain
Authors: Gagnon Etienne , Schubert David A. , Gordo Susana , Chu H. Hamlet , Wucherpfennig Kai W.
Published: November 2012

The CD3ε and ζ cytoplasmic domains of the T cell receptor bind to the inner leaflet of the plasma membrane (PM), and a previous nuclear magnetic resonance structure showed that both tyrosines of the CD3ε immunoreceptor tyrosine-based activation motif partition into the bilayer. Electrostatic interactions between acidic phospholipids and clusters of basic CD3ε residues were previously shown to be essential for CD3ε and ζ membrane binding. Phosphatidylserine (PS) is the most abundant negatively charged lipid on the inner leaflet of the PM and makes a major contribution to membrane binding by the CD3ε cytoplasmic domain. Here, we show that TCR triggering by peptide–MHC complexes induces dissociation of the CD3ε cytoplasmic domain from the plasma membrane. Release of the CD3ε cytoplasmic domain from the membrane is accompanied by a substantial focal reduction in negative charge and available PS in TCR microclusters. These changes in the lipid composition of TCR microclusters even occur when TCR signaling is blocked with a Src kinase inhibitor. Local changes in the lipid composition of TCR microclusters thus render the CD3ε cytoplasmic domain accessible during early stages of T cell activation.
Logarithmic Gromov-Witten invariants
Authors: Gross Mark , Siebert Bernd
Published: November 2012

The goal of this paper is to give a general theory of logarithmic Gromov-Witten invariants. This gives a vast generalization of the theory of relative Gromov-Witten invariants introduced by Li-Ruan, Ionel-Parker, and Jun Li and completes a program first proposed by the second named author in 2002. One considers target spaces

X
X

carrying a log structure. Domains of stable log curves are log smooth curves. Algebraicity of the stack of such stable log maps is proven, subject only to the hypothesis that the log structure on

X
X

is fine, saturated, and Zariski. A notion of basic stable log map is introduced; all stable log maps are pull-backs of basic stable log maps via base-change. With certain additional hypotheses, the stack of basic stable log maps is proven to be proper. Under these hypotheses and the additional hypothesis that

X
X

is log smooth, one obtains a theory of log Gromov-Witten invariants.
The digital read-out system CM—1: an instrument for rational measuring on radiographic headplates and dental models
Authors: Bondevik Olav , Røsler Marek , Slagsvold Olav
Published: November 2012

The design and mode of operation of a digital read-out system for rational measuring of radiographic headplates and dental models is described and the advantages and disadvantages of the instrument are discussed. The instrument allows direct reading of linear and angular measurements and of coordinates in a freely chosen coordinate system to a resolution of 0.1 mm and 0.1 degree. The instrument is connected to a teletype writer that can reproduce the results as hard copy print-outs and as punched paper tapes. Data can be transferred directly from the paper tapes to a computer for storage or calculation. Additionally the teletype can serve as a computer terminal with optional connection on-line with a computer.

In the conventional method of compiling data from radiographic headplates error can arise from landmark identification, tracing, measuring and recording. In the transfer of data to a computer the punching is another possible source of error. With the instrument described in this report, provided that it is in order and correctly operated, there is only one source of error, namely landmark identification.

The instrument is time-saving and simple to use. For clinical purposes direct measurement of linear and angular dimensions is the most rational approach but, in research, coordinate registration offers considerable advantages in that all parameters regularly used in roentgencephalometrics can be calculated by a computer on the basis of the coordinates of a relatively limited number of landmarks.
LEVER'S OBJECTIVES IN COLLECTING OLD FURNITURE
Authors: WOOD LUCY
Published: November 2012

Lever began acquiring old furniture in the 1870s and 1880s, first of all buying early English oak and then eighteenth-century French furntture. During the 1890s he turned to the Engltsh etghteenth century, and by 1900 was committed to forming an historically representatice collection ofEnglish furniture - the material equivalent of the various published histories that began to appear in the 1890s and 1900s. Several of the stylistic 'chapters 'were presented in period rooms, both in his houses and in the Lady Lerer Art Gallery. The major influence on Lever's career as a collector was the artist, dealer, collector and champion of British art, James Orrock , who saw furniture as an integral part of the British artistic achievement. Lever took this approach even further, seeking out mastetpieces of English cabinet-making that could vie with French furniture as works of art. At the same time he borrowed the moral clothing of the Vernacular Revival, paying lip-service to its cult of the ordinary object to endorse his deep-seated belief that art was good for people. It was this conviction, combined with his conrersion to Orrock's cause that led in 1913 to the foundation of the Lady Lever Art Gallery: the English furniture collection, selected by Lever from his own much larger holdings, remains one of the most important in public hands, and the late eighteenth-century marquetry is unrivalled.
Regulation of ribulose 1,5-bisphosphate carboxylase/oxygenase by metabolites
Authors: Servaites Jerome C. , Geiger Donald R.
Published: November 2012

Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and other enzymes and their common metabolites form a system regulated by feedforward and feedback mechanisms that is directly involved in assimilation of carbon. The interaction of these components in the chloroplast gives rise to properties, which can not be predicted from the study of isolated components alone. Experiments were conducted to explain how the observed pattern of system level regulation is consistent with the individual characteristics of Rubisco measured in vitro. In vitro Rubisco is responsive to a wide range of ribulose 1,5-bisphosphate and phosphoglycerate concentrations, similar to those found in leaves under field conditions. Metabolite regulation of carbon assimilation in vivo involves several processes. Among these are negative co-operativity of ribulose 1,5-bisphosphate binding by Rubisco, competitive inhibition of Rubisco by phosphoglycerate and inorganic phosphate, a high Rubisco active site concentration in the chloroplast, and maintenance of a constant phosphate concentration in the chloroplast resulting in reciprocal changes in the concentrations of ribulose 1,5-bisphosphate, phosphoglycerate and inorganic phosphate. High-light-grown plants exhibited higher assimilation rates than those growing under moderate light levels, but had similar Rubisco concentrations. Larger ribulose 1,5-bisphosphate/phosphoglycerate ratios in plants grown outdoors are responsible for the higher Rubisco activities and greater rates of carbon fixation observed under these conditions.
Integration of cytosolic and plastidic carbon metabolism by fructose 2,6-bisphosphate
Authors: Kruger Nicholas J. , Scott Peter
Published: November 2012

The aim of this report is to assess the role of fructose 2,6-bisphosphate (Fru-2,6-P2) in integration of metabolism between the cytosol and chloroplast during photosynthesis. Transgenic plants expressing modified copies of the rat liver bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase were used to obtain lines differing specifically in their Fru-2,6-P2 concentrations. Such plants differed in the quantum requirement for photosynthesis, rate of oxygen evolution, and the extent of fluorescence quenching at the onset of illumination. Increasing Fru-2,6-P2 resulted in a progressive increase in the period and number of oscillations in oxygen evolution and fluorescence following dark-light transition in saturating carbon dioxide. At the beginning of the photoperiod, transgenic lines with increased amounts of Fru-2,6-P2 showed greater starch accumulation and reduced fluxes to soluble sugars, organic acids and amino acids. In contrast, transgenic lines with reduced Fru-2,6-P2 concentrations accumulated sucrose more rapidly than untransformed plants, while the rate of starch synthesis was lower. The flux response coefficients for Fru-2,6-P2 on sucrose and starch synthesis were — 0.43 and 0.33, respectively. These results are interpreted as evidence that Fru-2,6-P2 makes a significant contribution to the potential limitation of photosynthesis by sucrose production in the cytosol.
Black hole mergers: do gas discs lead to spin alignment?
Authors: Lodato Giuseppe , Gerosa Davide
Published: November 2012

In this Letter, we revisit arguments suggesting that the Bardeen–Petterson effect can coalign the spins of a central supermassive black hole binary accreting from a circumbinary (or circumnuclear) gas disc. We improve on previous estimates by adding the dependence on system parameters and noting that the non-linear nature of warp propagation in a thin viscous disc affects alignment. This reduces the disc's ability to communicate the warp, and can severely reduce the effectiveness of disc-assisted spin alignment. We test our predictions with a Monte Carlo realization of random misalignments and accretion rates, and we find that the outcome depends strongly on the spin magnitude. We estimate a generous upper limit to the probability of alignment by making assumptions which favour it throughout. Even with these assumptions, about 40 per cent of black holes with a ≳ 0.5 do not have time to align with the disc. If the residual misalignment is not small and it is maintained down to the final coalescence phase, this can give a powerful recoil velocity to the merged hole. Highly spinning black holes are thus more likely being subject to strong recoils, the occurrence of which is currently debated.
Synthesis of Q base and related compounds
Authors: Ohgi Tadaaki , Kondo Tadao , Goto Toshio
Published: November 2012

Q base (6) and related compounds, 9 and 13, which could not be derived from the corresponding natural nucleosides, have been synthesized via the common key intermediate 2.
The Complexity of Aristotle's Study of Animals
Authors: Lennox James G.
Published: November 2012

Aristotle is the first person in the history of science to see the study of nature as an articulated complex of interrelated, yet somewhat autonomous, investigations. Understanding why goes to the heart of what is philosophically distinctive about him. Why does Aristotle present the investigation of “the common cause of animal motion” (as Aristotle characterizes the subject of De motu animalium) as distinct and independent from a study of the causes of the different forms of animal locomotion, the announced project of De incessu animalium? This article examines the puzzling complexity of Aristotle's investigations of animals, which can offer insights into his metaphysics and epistemology. It first briefly considers the range of Aristotle's writings related to animals, including Historia animalium, Dissections, De partibus animalium, De motu animalium, De incessu animalium, De Anima, and Meteorologica IV. The article then looks at his views on the limits of teleology in biology.
Performance Management: A Framework for Continuous Learning in Organizations
Authors: Mone Edward M.
Published: November 2012

Performance management, a critical business process, is discussed in this chapter as a framework for driving continuous learning at the individual, team, and organization levels, with an emphasis on the manager-employee relationship. The concepts of learning, continuous learning, and performance management are introduced, defined, and framed, setting the foundation for the subsequent discussion of each key component of the performance management process—goal setting, feedback, development, and appraisal—and its role in driving continuous learning. The discussion emphasizes the importance of goal cascading and alignment, the impact and influence of both performance and development goals on defining directions for continuous learning, understanding the conditions that enable the positive impact of feedback, knowing the factors that can promote employee development and continuous learning, and knowing how to use both informal and formal performance appraisals to identify, define, and plan for continuous learning. The chapter closes with a summary reinforcing the role of performance management as a framework for driving continuous learning in organizations.
Loop-Mediated Isothermal Amplification and Polymerase Chain Reaction Methods for Specific and Rapid Detection of Rhodococcus fascians
Authors: Serdani M. , Curtis M. , Miller M. L. , Kraus J. , Putnam M. L.
Published: November 2012

Rhodococcus fascians is a phytopathogenic actinobacterium which causes leafy galls and other plant distortions that result in economically significant losses to nurseries producing ornamental plants. Traditional assays for detection and identification are time-consuming and laborious. We developed a rapid polymerase chain reaction (PCR) diagnostic assay based on two primer pairs, p450 and fas, which target the fasA and fasD genes, respectively, that are essential for pathogenicity. We also developed a faster, more convenient, loop-mediated isothermal amplification (LAMP) assay targeting the fasR gene, which regulates expression of virulence genes. Both assays were evaluated for sensitivity and specificity in vitro and in planta. The p450 and fas primers amplified DNA only from pure cultures of pathogenic reference isolates of R. fascians. Nonpathogenic isolates and 51 other plant-associated bacteria were not amplified. The PCR primers correctly detected pathogenic R. fascians from 73 of 75 (97%) bacterial strains isolated from naturally infected plants. The PCR assay correctly discriminated between pathogenic R. fascians and other bacteria in 132 of 139 (95%) naturally infected plants, and in 34 of 34 (100%) artificially inoculated plants. The fas primers were slightly more accurate than the p450 primers. The LAMP assay accurately detected pathogenic R. fascians in 26 of 28 (93%) naturally infected plants and did not react with 23 asymptomatic plants. The LAMP primers also amplified product for DNA extracts of 40 of 41 bacterial strains isolated from plants with leafy galls. The detection limit of both the PCR and LAMP assays was approximately 103 CFU/30-μl reaction. These new tools allow fast, reliable, and accurate detection of R. fascians in vitro and in planta. The LAMP assay in particular is a significant advancement in rapid R. fascians diagnostics, and enables those with limited laboratory facilities to confirm the presence of this pathogen in infected plants.
Pecan Scab Severity—Effects of Assessment Methods
Authors: Bock Clive H. , Wood Bruce W. , Gottwald Tim R.
Published: November 2012

Pecan scab is caused by the fungus Fusicladium effusum, and is the most destructive disease of pecan in the United States. Accurate and reliable disease assessments are needed to ensure that data provide a measure of actual disease intensity. The Horsfall-Barratt (H-B) category scale and its derivatives are commonly used to assess disease. Estimates using the H-B scale were compared with nearest percent estimate (NPEs) for rating disease severity of pecan scab on valves of fruit. Both inexperienced and experienced raters were included in the experiment. Lin's concordance correlation showed that agreement using NPEs was variable (ρc = 0.57 to 0.96), whereas estimates of disease severity using the H-B scale had similar agreement among most raters (ρc = 0.59 to 0.98). Converted values of NPEs to the H-B midpoints (NPEH-B) also provided a similar range (ρc = 0.61 to 0.96). Neither experienced nor inexperienced raters were consistently better using any of the three methods. Bootstrap analysis indicated that, among experienced raters, precision (r) and agreement (ρc) were often reduced when using the H-B scale compared with NPEs. There was no consistent effect of converting NPEs to NPEH-B midpoint values compared with actual H-B values. Inter-rater reliability using the H-B scale was never better than NPEs. Bootstrap analysis indicated no difference in the length of time needed to assess disease but regression analysis suggested that raters who were inherently fast in assessing disease with NPEs were often slower when using the H-B scale; conversely, raters who were slow assessing with NPEs were often faster when using the H-B scale. Thus, there appears to be no advantage in accuracy or reliability or reduction in time when inexperienced or experienced raters used a category rating scale to assess pecan scab.
Effects of Contrast Agent and Outer Volume Saturation Bands on Water Suppression and Shimming of Hepatic Single-Volume Proton MR Spectroscopy at 3.0T
Authors: Xu Li , Huang Yan , Liu Xian , Liu Bo
Published: November 2012

Purpose. To determine whether administration of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) and whether placement of the outer volume saturation bands significantly affect shimming and water suppression on hepatic MR spectroscopic prescanning.Method. Region of interest (ROI) of 2 cm × 2 cm × 2 cm was carefully positioned in the region of the middle portion of the right hepatic lobe. 32 patients were examined before and after administration of Gd-DTPA with and without outer-volume saturation bands. Linewidths (Full-Width Half-Maximum (FWHM)) and water suppression were obtained. A pairedt-test for comparison of means was used.Results. (1) The group with the outer volume saturation bands demonstrated slightly better water suppression effect than the group without outer volume saturation bands before administration. (2) The group with the outer volume saturation bands demonstrated better water suppression effect than the group without outer volume saturation bands after administration. (3) Both shimming and water suppression effectswere decreased on enhanced MR spectroscopic prescanning (allP<0.05).Conclusions. Placement of the outer volume saturation bands is helpful to improve water suppression both before and after contrast agent administration. Gd-DTPA exerts a slightly adverse effect (a statistically significant but clinically unimportant) on magnetic resonance spectroscopic prescanning at 3T.