bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of cutting direction of cork planks on the quality and porosity characteristics of natural cork stoppers
Authors: Costa A. , Pereira H.
Published: July 2014

In the industrial production of natural cork stoppers, cork planks are cut transversely into strips and stoppers are
bored in the axial direction, therefore with their cylinder axis parallel to the tree axial direction. The influence of
cutting direction of cork planks (transverse or longitudinal), and therefore the orientation of stoppers cylindrical axis (longitudinal or tangential, respectively) on yields, quality profile and porosity characteristics was studied in a random sampling of planks of different quality classes that were bored to produce 45 mm × 24 mm stoppers. The stoppers quality profile and production values were not influenced by the cutting direction, although in good quality planks (1st/2nd) the longitudinal cut led to a higher proportion of good quality stoppers in comparison to the transversal cut, 32% vs. 23%. Regarding porosity characteristics, pore orientation differed between the two cutting directions but not the porosity coefficient, with the exception of the poor quality classes.
An Alarming Lack of Feeling: Urban Travel, Emotions, and British National Character in Post-Revolutionary Paris
Authors: Thompson Victoria E.
Published: July 2014

This article analyzes British narratives of voyages made to Paris during three periods: the Peace of Amiens (March 1802 to May 1803), the first Restoration (April 1814 to May 1815), and in the first few years of the second Restoration (June 1815 to ca. 1820). These accounts reveal a consistent use of strong and distressing expressions of emotion when describing locations in the city associated with the events of the French Revolution. An analysis of these “emotional landmarks” allows us to understand the role of trauma in unsettling distinctions between the British and French in the aftermath of the Revolution. It also demonstrates that travel writers participated in an emotional community consistent with the nation, one that used these emotional landmarks to establish a new distinction between the two national characters based on emotion.
The Role of Emotions in Protests against Modernist Urban Redevelopment in Perth and Halifax
Authors: Gregory Jenny , Grant Jill L.
Published: July 2014

In the 1950s and 1960s modernist town planning reordered countless cities through urban renewal and freeway-building projects. Applying rational planning expertise generated emotional responses that often lingered long after redevelopment occurred. This article considers the emotional response to urban renewal in two cities advised by the British town planner Gordon Stephenson. In Perth, Australia, Stephenson was amongst a group of experts who planned a freeway that obliterated part of the valued river environment and threatened a historic structure. In Halifax, Stephenson prepared the initial scientific study used to justify dismantling part of the downtown and a historic black community on the urban fringe. While the Perth case generated an explosion of emotional intensity that failed to prevent environmental despoliation but saved some heritage assets, the Halifax example initiated a lingering emotional dispute involving allegations of neglect and racism. Comparing cases resulting from the activities of a noted practitioner illustrates differing emotional trajectories produced in the wake of the modernist planning project.
Core promoter factor TAF9B regulates neuronal gene expression
Authors: Herrera Francisco J , Yamaguchi Teppei , Roelink Henk , Tjian Robert
Published: July 2014

Emerging evidence points to an unexpected diversification of core promoter recognition complexes that serve as important regulators of cell-type specific gene transcription. Here, we report that the orphan TBP-associated factor TAF9B is selectively up-regulated upon in vitro motor neuron differentiation, and is required for the transcriptional induction of specific neuronal genes, while dispensable for global gene expression in murine ES cells. TAF9B binds to both promoters and distal enhancers of neuronal genes, partially co-localizing at binding sites of OLIG2, a key activator of motor neuron differentiation. Surprisingly, in this neuronal context TAF9B becomes preferentially associated with PCAF rather than the canonical TFIID complex. Analysis of dissected spinal column from Taf9b KO mice confirmed that TAF9B also regulates neuronal gene transcription in vivo. Our findings suggest that alternative core promoter complexes may provide a key mechanism to lock in and maintain specific transcriptional programs in terminally differentiated cell types.
Induction of homologous recombination between sequence repeats by the activation induced cytidine deaminase (AID) protein
Authors: Buerstedde Jean-Marie , Lowndes Noel , Schatz David G
Published: July 2014

The activation induced cytidine deaminase (AID) protein is known to initiate somatic hypermutation, gene conversion or switch recombination by cytidine deamination within the immunoglobulin loci. Using chromosomally integrated fluorescence reporter transgenes, we demonstrate a new recombinogenic activity of AID leading to intra- and intergenic deletions via homologous recombination of sequence repeats. Repeat recombination occurs at high frequencies even when the homologous sequences are hundreds of bases away from the positions of AID-mediated cytidine deamination, suggesting DNA end resection before strand invasion. Analysis of recombinants between homeologous repeats yielded evidence for heteroduplex formation and preferential migration of the Holliday junctions to the boundaries of sequence homology. These findings broaden the target and off-target mutagenic potential of AID and establish a novel system to study induced homologous recombination in vertebrate cells.
The inherent mutational tolerance and antigenic evolvability of influenza hemagglutinin
Authors: Thyagarajan Bargavi , Bloom Jesse D
Published: July 2014

Influenza is notable for its evolutionary capacity to escape immunity targeting the viral hemagglutinin. We used deep mutational scanning to examine the extent to which a high inherent mutational tolerance contributes to this antigenic evolvability. We created mutant viruses that incorporate most of the ≈104 amino-acid mutations to hemagglutinin from A/WSN/1933 (H1N1) influenza. After passaging these viruses in tissue culture to select for functional variants, we used deep sequencing to quantify mutation frequencies before and after selection. These data enable us to infer the preference for each amino acid at each site in hemagglutinin. These inferences are consistent with existing knowledge about the protein's structure and function, and can be used to create a model that describes hemagglutinin's evolution far better than existing phylogenetic models. We show that hemagglutinin has a high inherent tolerance for mutations at antigenic sites, suggesting that this is one factor contributing to influenza's antigenic evolution.
New volcanoes discovered in southeast Australia
Authors: Wendel JoAnna
Published: July 2014

Scientists have discovered three new active volcanoes in the Newer Volcanics Province (NVP) in southeast Australia. Researchers from Monash University in Melbourne describe in the Australian Journal of Earth Sciences how they used a combination of satellite photographs, detailed topography models from NASA, the distribution of magnetic minerals in the rocks, and site visits to analyze the region.
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Authors: Howard Claire
Published: July 2014

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Sea level and climate forcing of the Sr isotope composition of lateMioceneMediterranean marine basins
Authors: Schildgen T. F. , Cosentino D. , Frijia G. , Castorina F. , Dudas F. Ö. , Iadanza A. , Sampalmieri G. , Cipollari P. , Caruso A. , Bowring S. A. , Strecker M. R.
Published: July 2014

Sr isotope records from marginal marine basins track the mixing between seawater and local continental runoff, potentially recording the effects of sea level, tectonic, and climate forcing in marine fossils and sediments. Our 110 new87Sr/86Sr analyses on oyster and foraminifera samples from six late Miocene stratigraphic sections in southern Turkey, Crete, and Sicily show that87Sr/86Sr fell below global seawater values in the basins several million years before the Messinian Salinity Crisis, coinciding with tectonic uplift and basin shallowing.87Sr/86Sr from more centrally located basins (away from the Mediterranean coast) drop below global seawater values only during the Messinian Salinity Crisis. In addition to this general trend, 55 new87Sr/86Sr analyses from the astronomically tuned Lower Evaporites in the central Apennines (Italy) allow us to explore the effect of glacio‐eustatic sea level and precipitation changes on87Sr/86Sr. Most variation in our data can be explained by changes in sea level, with greatest negative excursions from global seawater values occurring during relative sea level lowstands, which generally coincided with arid conditions in the Mediterranean realm. We suggest that this greater sensitivity to lowered sea level compared with higher runoff could relate to the inverse relationship between Sr concentration and river discharge. Variations in the residence time of groundwater within the karst terrain of the circum‐Mediterranean region during arid and wet phases may help to explain the single (robust) occurrence of a negative excursion during a sea level highstand, but this explanation remains speculative without more detailed paleoclimatic data for the region.
Needs before Tools: Using Technology in Environmental Conflict Resolution
Authors: Cravens Amanda E.
Published: July 2014

Environmental conflict resolution practitioners have become increasingly interested in using information technology to work collaboratively across sectors. Discussions to date, however, have focused on specific tools rather than the underlying objectives that software can accomplish. Technology, like any other technique in a practitioner's repertoire, is a solution to a specific challenge identified through reflection‐in‐action. Explicitly defining the needs one wishes software to meet prevents using technology for technology's sake, provides criteria to choose between similar products or evaluate a tool's success, and helps identify needs for which suitable tools do not currently exist.
Highly Crystalline Lithium Titanium Oxide Sheets Coated with Nitrogen‐Doped Carbon enable High‐Rate Lithium‐Ion Batteries
Authors: Han Cuiping , He Yan‐Bing , Li Baohua , Li Hongfei , Ma Jun , Du Hongda , Qin Xianying , Yang Quan‐Hong , Kang Feiyu
Published: July 2014

Sheets of Li4Ti5O12 with high crystallinity are coated with nitrogen‐doped carbon (NC‐LTO) using a controlled process, comprising hydrothermal reaction followed by chemical vapor deposition (CVD). Acetonitrile (CH3CN) vapor is used as carbon and nitrogen source to obtain a thin coating layer of nitrogen‐doped carbon. The layer enables the NC‐LTO material to maintain its sheet structure during the high‐temperature CVD process and to achieve high crystallinity. Doping with nitrogen introduces defects into the carbon coating layer, and this increased degree of disorder allows fast transportation of lithium ions in the layer. An electrode of NC‐LTO synthesized at 700 °C exhibits greatly improved rate and cycling performance due to a markedly decreased total cell resistance and enhanced Li‐ion diffusion coefficient (DLi). Specific capacities of 159.2 and 145.8 mA h g−1 are obtained using the NC‐LTO sheets, at charge/discharge rates of 1 and 10 C, respectively. These values are much higher than values for LTO particles did not undergo the acetonitrile CVD treatment. A capacity retention value as high as 94.7 % is achieved for the NC‐LTO sheets after 400 cycles in a half‐cell at 5 C discharge rate.
Autophagy defects suggested by low levels of autophagy activator MAP1S and high levels of autophagy inhibitor LRPPRC predict poor prognosis of prostate cancer patients
Authors: Jiang Xianhan , Zhong Weide , Huang Hai , He Huichan , Jiang Funeng , Chen Yanru , Yue Fei , Zou Jing , Li Xun , He Yongzhong , You Pan , Yang Weiqiang , Lai Yiming , Wang Fen , Liu Leyuan
Published: July 2014

MAP1S (originally named C19ORF5) is a widely distributed homolog of neuronal‐specific MAP1A and MAP1B, and bridges autophagic components with microtubules and mitochondria to affect autophagosomal biogenesis and degradation. Mitochondrion‐associated protein LRPPRC functions as an inhibitor for autophagy initiation to protect mitochondria from autophagy degradation. MAP1S and LRPPRC interact with each other and may collaboratively regulate autophagy although the underlying mechanism is yet unknown. Previously, we have reported that LRPPRC levels serve as a prognosis marker of patients with prostate adenocarcinomas (PCA), and that patients with high LRPPRC levels survive a shorter period after surgery than those with low levels of LRPPRC. MAP1S levels are elevated in diethylnitrosamine‐induced hepatocelular carcinomas in wildtype mice and the exposed MAP1S‐deficient mice develop more malignant hepatocellular carcinomas. We performed immunochemical analysis to evaluate the co‐relationship among the levels of MAP1S, LRPPRC, P62, and γ‐H2AX. Samples were collected from wildtype and prostate‐specific PTEN‐deficient mice, 111 patients with PCA who had been followed up for 10 years and 38 patients with benign prostate hyperplasia enrolled in hospitals in Guangzhou, China. The levels of MAP1S were generally elevated so the MAP1S‐mediated autophagy was activated in PCA developed in either PTEN‐deficient mice or patients than their respective benign tumors. The MAP1S levels among patients with PCA vary dramatically, and patients with low MAP1S levels survive a shorter period than those with high MAP1S levels. Levels of MAP1S in collaboration with levels of LRPPRC can serve as markers for prognosis of prostate cancer patients. © 2014 Wiley Periodicals, Inc.
Overexpression of DNAJB6 promotes colorectal cancer cell invasion through an IQGAP1/ERK‐dependent signaling pathway
Authors: Zhang Tong‐Tong , Jiang Yan‐Yi , Shang Li , Shi Zhi‐Zhou , Liang Jian‐Wei , Wang Zheng , Zhang Yu , Hao Jia‐Jie , Jia Xue‐Mei , Xu Xin , Cai Yan , Zhan Qi‐Min , Wang Ming‐Rong
Published: July 2014

DNAJB6 is a member of the heat shock protein 40 (Hsp40) family. We here investigated the clinical correlation and biological role of DNAJB6 overexpression in colorectal cancer (CRC). The expression of DNAJB6 protein was examined in 200 cases of colorectal adenocarcinomas by immunohistochemistry (IHC) technology. Gene transfection and RNA interference were performed to determine the effect of DNAJB6 expression on the invasion of CRC cells and to explore the underlying molecular mechanisms in vitro and in vivo. Overexpression of DNAJB6 was found in 39% (78/200) of the CRC tissues, especially in tumors at pT4 as compared with at pT1–3 (P = 0.02). A Kaplan–Meier survival analysis revealed a correlation between DNAJB6 expression and overall survival (OS) times (P = 0.003). Multivariate analysis confirmed that DNAJB6 overexpression was an independent prognostic factor for CRC (P = 0.002). RNA interference‐mediated silencing of the DNAJB6 gene inhibited the invasion of CRC cells in vitro were accompanied by a significant reduction in the protein levels of IQ‐domain GTPase‐activating protein 1 (IQGAP1) and phosphorylated ERK (pERK). An in vivo assay showed that inhibition of DNAJB6 expression decreased the lung metastases of CRC cells. IHC analysis of serial sections showed that there was a positive correlation between DNAJB6 and IQGAP1 expression in primary CRC tissues (P = 0.013). The data suggest that DNAJB6 plays an important oncogenic role in CRC cell invasion by up‐regulating IQGAP1 and activating the ERK signaling pathway and that DNAJB6 may be used as a prognostic marker for CRC. © 2014 Wiley Periodicals, Inc.
Reliability Analysis Using Chaotic Particle Swarm Optimization
Authors: Zhao Hongbo , Ru Zhongliang , Chang Xu , Li Shaojun
Published: July 2014

Reliability analysis is an important and practical way of considering uncertainty in an engineering system. In practical engineering, the limit state functions are usually implicit in terms of random variables. Traditional reliability analysis methods are time‐consuming and require derivative computing. In this paper, particle swarm optimization (PSO) is applied to reliability analysis by combining it with the first‐order reliability method. To improve the global search performance, chaotic PSO (CPSO) was proposed by combining PSO with a chaotic system. CPSO‐based reliability analysis is described and applied to four classic examples. The results show that implementation of CPSO‐based reliability analysis is easy and can yield a reliability index and design point with good accuracy. The proposed method was applied to analyze the reliability of a circular tunnel in different cases. The results show that the CPSO algorithm is very efficient at solving global optimization problems and is a good approach for reliability analysis. Copyright © 2014 John Wiley & Sons, Ltd.
A New Exponentially Weighted Moving Average Control Chart for Monitoring the Process Mean
Authors: Haq Abdul , Brown Jennifer , Moltchanova Elena
Published: July 2014

Exponentially weighted moving average (EWMA) quality control schemes have been recognized as a potentially powerful process monitoring tool because of their superior speed in detecting small to moderate shifts in the underlying process parameters. In quality control literature, there exist several EWMA charts that are based on simple random sampling (SRS) and ranked set sampling (RSS) schemes. Recently, a mixed RSS (MxRSS) scheme has been introduced, which encompasses both SRS and RSS schemes, and is a cost‐effective alternative to the RSS scheme. In this paper, we propose new EWMA control charts for efficiently monitoring the process mean based on MxRSS and imperfect MxRSS (IMxRSS) schemes, named EWMA–MxRSS and EWMA–IMxRSS charts, respectively. Extensive Monte Carlo simulations are used to estimate the run length characteristics of the proposed EWMA charts. The run length performances of the suggested EWMA charts are compared with the classical EWMA chart based on SRS (EWMA–SRS). It turns out that both EWMA–MxRSS and EWMA–IMxRSS charts perform uniformly better than the EWMA–SRS chart when detecting all different shifts in the process mean. An application to a real data set is provided as an illustration of the design and implementation of the proposed EWMA chart. Copyright © 2014 John Wiley & Sons, Ltd.
Structure and function of pseudoknots involved in gene expression control
Authors: Peselis Alla , Serganov Alexander
Published: July 2014

Natural RNA molecules can have a high degree of structural complexity but even the most complexly folded RNAs are assembled from simple structural building blocks. Among the simplest RNA elements are double‐stranded helices that participate in the formation of different folding topologies and constitute the major fraction of RNA structures. One common folding motif of RNA is a pseudoknot, defined as a bipartite helical structure formed by base‐pairing of the apical loop in the stem‐loop structure with an outside sequence. Pseudoknots constitute integral parts of the RNA structures essential for various cellular activities. Among many functions of pseudoknotted RNAs is feedback regulation of gene expression, carried out through specific recognition of various molecules. Pseudoknotted RNAs autoregulate ribosomal and phage protein genes in response to downstream encoded proteins, while many metabolic and transport genes are controlled by cellular metabolites interacting with pseudoknotted RNA elements from the riboswitch family. Modulation of some genes also depends on metabolite‐induced messenger RNA (mRNA) cleavage performed by pseudoknotted ribozymes. Several regulatory pseudoknots have been characterized biochemically and structurally in great detail. These studies have demonstrated a plethora of pseudoknot‐based folds and have begun uncovering diverse molecular principles of the ligand‐dependent gene expression control. The pseudoknot‐mediated mechanisms of gene control and many unexpected and interesting features of the regulatory pseudoknots have significantly advanced our understanding of the genetic circuits and laid the foundation for modulation of their outcomes. WIREs RNA 2014, 5:803–822. doi: 10.1002/wrna.1247

This article is categorized under:

RNA Structure and Dynamics > RNA Structure, Dynamics, and Chemistry

RNA Interactions with Proteins and Other Molecules > Protein–RNA Recognition

RNA Interactions with Proteins and Other Molecules > Small Molecule–RNA Interactions
In Operando GIXRD and XRR on Polycrystalline In52Pd48
Authors: Ivarsson Dennis C. A. , Neumann Matthias , Levin Alexander A. , Keilhauer Toni , Wochner Peter , Armbrüster Marc
Published: July 2014

A combined approach of grazing incidence X‐ray diffraction (GIXRD) and X‐ray reflectivity (XRR) under in operando conditions on polycrystalline materials is presented. This approach allows tracking of material changes of amorphous or crystalline nature in the near‐surface region. Crystalline phases formed in operando can be identified by X‐ray diffraction, while by XRR measurements information about the thickness and the density of overlayers is obtained. The setup also allows collection of data generated with higher incident angles which permit a direct comparison of the changes close to the surface and in the bulk of the materials. Results for the composition In52Pd48 – a mixture of the intermetallic compounds InPd and In3Pd2 catalyzing the steam reforming of methanol – in reducing atmosphere and under methanol steam reforming (MSR) conditions are presented. InPd exhibits a dynamic behavior, reacting to changes in atmosphere and temperature. The combination of GIXRD and XRR proves to be a powerful tool to examine model catalysts under catalytically relevant conditions providing complementary information to other methods.
HAAVELMO’S PROBABILITY APPROACH AND THE COINTEGRATED VAR
Authors: Juselius Katarina
Published: July 2014

Some key econometric concepts and problems of great importance to Trygve Haavelmo and Ragnar Frisch are discussed within the general framework of a cointegrated VAR. The focus is on problems typical of time-series data such as multicollinearity, spurious correlation and regression, time dependent residuals, model selection, missing simultaneity, autonomy, and identification. The paper argues that the more recent development of unit root econometrics has been instrumental for a solution to the above problems.
Autism and nutrition: the role of the gut–brain axis
Authors: van De Sande Marijke M. H. , van Buul Vincent J. , Brouns Fred J. P. H.
Published: July 2014

Autism spectrum disorder (ASD) is characterised by deficits in the ability to socialise, communicate and use imagination, and displays of stereotypical behaviour. It is widely accepted that ASD involves a disorder in brain development. However, the real causes of the neurodevelopmental disorders associated with ASD are not clear. In this respect, it has been found that a majority of children with ASD display gastrointestinal symptoms, and an increased intestinal permeability. Moreover, large differences in microbiotic composition between ASD patients and controls have been reported. Therefore, nutrition-related factors have been hypothesised to play a causal role in the aetiology of ASD and its symptoms. Through a review of the literature, it was found that abnormalities in carbohydrate digestion and absorption could explain some of the gastrointestinal problems observed in a subset of ASD patients, although their role in the neurological and behavioural problems remains uncertain. In addition, the relationship between an improved gut health and a reduction of symptoms in some patients was evaluated. Recent trials involving gluten-free diets, casein-free diets, and pre- and probiotic, and multivitamin supplementation show contradictive but promising results. It can be concluded that nutrition and other environmental influences might trigger an unstable base of genetic predisposition, which may lead to the development of autism, at least in a subset of ASD patients. Clear directions for further research to improve diagnosis and treatment for the different subsets of the disorder are provided.
Sportliche (In-)Aktivität depressiver Patienten
Authors: Grimm Nina C. I. , Krämer Lena V.
Published: July 2014

Theoretischer Hintergrund: Der Health Action Process Approach (HAPA) wurde dazu genutzt, die kognitiven Grundlagen des Sportverhaltens depressiver Patienten näher zu beschreiben. Fragestellung: Das Ziel bestand darin, depressive Patienten anhand von Prozessen der sportbezogenen Absichtsbildung (Motivation) und Absichtsumsetzung (Volition) zu typisieren. Methode: 62 depressive Patienten erhielten Selbstbeurteilungsfragebögen zu sportbezogenen Variablen. Die Typisierung erfolgte mittels einer Clusteranalyse. Ergebnisse: Es ergaben sich vier Cluster: Das erste Cluster wies keine Sportabsicht auf (Non-Intender), das zweite Cluster eine mittelstarke Absicht (Medium-Intender). Das dritte Cluster war charakterisiert durch eine hohe Absichtsstärke, bei mangelnder Absichtsumsetzung (High-Intender). Das vierte Cluster wies eine hohe Absichtsstärke sowie eine gelungene Absichtsumsetzung auf (Actor). Schlussfolgerung: Depressive Patienten sollten unseren Daten zufolge in vier sportbezogene Typen unterteilt werden. Anhand der Clusterprofile können typspezifische Interventionen zur Steigerung sportlicher Aktivität abgeleitet werden.
Facile one-pot synthesis of a aptamer-based organic–silica hybrid monolithic capillary column by “thiol–ene” click chemistry for detection of enantiomers of chemotherapeutic anthracyclines
Authors: Jiang Han-Peng , Zhu Jiu-Xia , Peng Chunyan , Gao Jiajia , Zheng Fang , Xiao Yu-Xiu , Feng Yu-Qi , Yuan Bi-Feng
Published: July 2014

Preparation of aptamer-based organic–silica hybrid monolithic capillary column by “thiol–ene” click chemistry for the detection of the enantiomers of chemotherapeutic anthracyclines.
Stabilization of β-peptide helices by direct attachment of trifluoromethyl groups to peptide backbones
Authors: Cho Joonil , Sawaki Kyohei , Hanashima Shinya , Yamaguchi Yoshiki , Shiro Motoo , Saigo Kazuhiko , Ishida Yasuhiro
Published: July 2014

Direct attachment of trifluoromethyl groups to peptide backbones was found to be a novel strategy for peptide folding stabilization, where the intramolecular hydrogen-bonding ability of backbone amides is enhanced.
Milk quality control: instant and quantitative milk fat determination with a BODIPY sensor-based fluorescence detector
Authors: Xu Wang , Bai Jiaojiao , Peng Juanjuan , Samanta Animesh , Divyanshu Divyanshu , Chang Young-Tae
Published: July 2014

The first fluorescent sensor for milk fat was developed.
Self-assembly of long chain fatty acids: effect of a methyl branch
Authors: Liljeblad Jonathan F. D. , Tyrode Eric , Thormann Esben , Dublanchet Ann-Claude , Luengo Gustavo , Magnus Johnson C. , Rutland Mark W.
Published: July 2014

The morphology and molecular conformation of monolayers of straight chain and methyl-branched fatty acids have been investigated by VSFS and AFM, revealing domains in the latter case, due to inverse micellar packing constraints.
Low-loss latching microwave switch using thermally pulsed non-volatile chalcogenide phase change materials
Authors: El-Hinnawy Nabil , Borodulin Pavel , Wagner Brian P. , King Matthew R. , Jones Evan B. , Howell Robert S. , Lee Michael J. , Young Robert M.
Published: July 2014

A high performance RF (radio-frequency) switch based on the phase change effect in germanium-telluride (GeTe) is described. Thermal pulses applied to a separate independent thin film heating element for 0.1–1.5 μs toggles the switch in a latching fashion. Being non-volatile, no power is required to hold the switch in the on- or off-state. State-of-the-art solid-state RF switches currently in use have an on-state loss of 1 dB; here, we demonstrate an inline phase change switch with a low on-state resistance showing over a frequency range of 0-40 GHz an insertion loss of just 0.1–0.24 dB.
A new neutron time-of-flight detector for fuel-areal-density measurements on OMEGA
Authors: Glebov V. Yu. , Forrest C. J. , Marshall K. L. , Romanofsky M. , Sangster T. C. , Shoup M. J. , Stoeckl C.
Published: July 2014

A new neutron time-of-flight (nTOF) detector for fuel-areal-density measurements in cryogenic DT implosions was installed on the OMEGA Laser System. The nTOF detector has a cylindrical thin-wall, stainless-steel, 8-in.-diam, 4-in.-thick cavity filled with an oxygenated liquid xylene scintillator. Four gated photomultiplier tubes (PMTs) with different gains are used to measure primary DT and D2 neutrons, down-scattered neutrons in nT and nD kinematic edge regions, and to study tertiary neutrons in the same detector. The nTOF detector is located 13.4 m from target chamber center in a well-collimated line of sight. The design details of the nTOF detector, PMT optimization, and test results on OMEGA will be presented.
Anisotropic In distribution in InGaN core-shell nanowires
Authors: Leclere C. , Katcho N. A. , Tourbot G. , Daudin B. , Proietti M. G. , Renevier H.
Published: July 2014

In this work, we investigate the local atomic structure of defect-free homogeneous and self-organized core-shell structure nanowires by means of X-ray Absorption Fine Structure (XAFS) Spectroscopy at the In LIII and K edges and Multiwavelength Anomalous Diffraction. The results are interpreted by comparison of the experimental data with X-ray absorption calculations carried out with ab initio structural models. Extended-XAFS data analysis at In K-edge shows an anisotropic In distribution in the second nearest neighbors pointing out to a deviation from randomness in In distribution for the core-shell sample.
High-refractive-index CuI waveguide with aligned cylindrical micropores for high-resolution X-ray imaging
Authors: Ohashi Yoshihiro , Yasui Nobuhiro , Den Toru
Published: July 2014

We have fabricated porous CuI crystals and used them as scintillator plates for high-resolution X-ray imaging by combining the properties of high-refractive-index light waveguide and scintillation. Porous CuI crystals containing aligned cylindrical micropores with pore volumes of 6% and 30% were fabricated by leaching directionally solidified CuI/NaCl and CuI/KCl eutectic crystals. The continuous cylindrical pores, which had a smooth surface, extended inward from the front to the back surface of the CuI crystal; therefore, light is confined in the CuI matrix with high refractive index (n ≈ 2.35) and transported along the pore direction by a total reflection mode. High-resolution X-ray imaging was demonstrated by using a 30% pore volume CuI crystal for an X-ray resolution chart and the 10 lp/mm pattern was clearly resolved.
Terahertz spectroscopy on hole transport in pentacene thin films
Authors: Engelbrecht S. G. , Prinz M. , Arend T. R. , Kersting R.
Published: July 2014

Charge transport in pentacene thin films is investigated using terahertz electromodulation spectroscopy. Although the material is highly polycrystalline, a hole mobility of about 20 cm2/Vs is found, which exceeds the mobility obtained in DC measurements by orders of magnitude. The high AC mobility results from a motion of charge carriers, which is not hindered by grain boundaries. An upper limit of mh*≈0.8 me is deduced for the conductivity effective mass of holes in pentacene.
Thermally activated delayed fluorescence from 3nπ* to 1nπ* up-conversion and its application to organic light-emitting diodes
Authors: Li Jie , Zhang Qisheng , Nomura Hiroko , Miyazaki Hiroshi , Adachi Chihaya
Published: July 2014

Intense nπ* fluorescence from a nitrogen-rich heterocyclic compound, 2,5,8-tris(4-fluoro-3-methylphenyl)-1,3,4,6,7,9,9b-heptaazaphenalene (HAP-3MF), is demonstrated. The overlap-forbidden nature of the nπ* transition and the higher energy of the 3ππ* state than the 3nπ* one lead to a small energy difference between the lowest singlet (S1) and triplet (T1) excited states of HAP-3MF. Green-emitting HAP-3MF has a moderate photoluminescence quantum yield of 0.26 in both toluene and doped film. However, an organic light-emitting diode containing HAP-3MF achieved a high external quantum efficiency of 6.0%, indicating that HAP-3MF harvests singlet excitons through a thermally activated T1 → S1 pathway in the electroluminescent process.
Resonant metallic nanostructure for enhanced two-photon absorption in a thin GaAs p-i-n diode
Authors: Portier Benjamin , Vest Benjamin , Pardo Fabrice , Péré-Laperne Nicolas , Steveler Emilie , Jaeck Julien , Dupuis Christophe , Bardou Nathalie , Lemaître Aristide , Rosencher Emmanuel , Haïdar Riad , Pelouard Jean-Luc
Published: July 2014

Degenerate two-photon absorption (TPA) is investigated in a 186 nm thick gallium arsenide (GaAs) p-i-n diode embedded in a resonant metallic nanostructure. The full device consists in the GaAs layer, a gold subwavelength grating on the illuminated side, and a gold mirror on the opposite side. For TM-polarized light, the structure exhibits a resonance close to 1.47 μm, with a confined electric field in the intrinsic region, far from the metallic interfaces. A 109 times increase in photocurrent compared to a non-resonant device is obtained experimentally, while numerical simulations suggest that both gain in TPA-photocurrent and angular dependence can be further improved. For optimized grating parameters, a maximum gain of 241 is demonstrated numerically and over incidence angle range of (−30°; +30°).
DEAD-box protein CYT-19 is activated by exposed helices in a group I intron RNA
Authors: Jarmoskaite Inga , Bhaskaran Hari , Seifert Soenke , Russell Rick
Published: July 2014

Significance

DEAD-box proteins are ubiquitous in RNA metabolism and can act as RNA chaperones by promoting folding and rearrangements of structured RNAs. However, the mechanistic basis for these chaperone activities is not well understood. Here we show that the DEAD-box protein CYT-19 unfolds a large, structured RNA molecule in a stability-dependent fashion and is more active toward less compact conformations of the RNA. Our results indicate that CYT-19 functions predominantly by disrupting accessible RNA secondary structure and depends on spontaneous openings in tightly packed RNAs to gain access to RNA helices. Unwinding of exposed secondary structure promotes global RNA unfolding and facilitates formation of new structures. Analogous mechanisms are observed in other molecular chaperones and are likely widespread among DEAD-box helicases.
Proton transfers are key elementary steps in ethylene polymerization on isolated chromium(III) silicates
Authors: Delley Murielle F. , Núñez-Zarur Francisco , Conley Matthew P. , Comas-Vives Aleix , Siddiqi Georges , Norsic Sébastien , Monteil Vincent , Safonova Olga V. , Copéret Christophe
Published: July 2014

Significance

The Phillips catalyst—CrO
x
/SiO
2
—produces 40–50% of global high-density polyethylene, yet several fundamental mechanistic controversies surround this catalyst. What is the oxidation state and nuclearity of the active Cr sites? How is the first Cr–C bond formed? How does the polymer propagate and regulate its molecular weight? Here we show through combined experimental (infrared, ultraviolet-visible, X-ray near edge absorption spectroscopy, and extended X-ray absorption fine structures) and density functional theory modeling approaches that mononuclear tricoordinate Cr(III) sites immobilized on silica polymerize ethylene by the classical Cossee–Arlman mechanism. Initiation (C–H bond activation) and polymer molecular weight regulation (the microreverse of C–H activation) are controlled by proton transfer steps.
Molecular mechanisms for the regulation of histone mRNA stem-loop–binding protein by phosphorylation
Authors: Zhang Jun , Tan Dazhi , DeRose Eugene F. , Perera Lalith , Dominski Zbigniew , Marzluff William F. , Tong Liang , Hall Traci M. Tanaka
Published: July 2014

Significance

As DNA is replicated during cell division, it must be packaged by histones. To match the level of available histones to DNA replication, histone mRNA expression is controlled by a 3′-end stem-loop structure unique to replication-dependent histone mRNAs. InDrosophila, this regulation is mediated by histone mRNA stem-loop–binding protein (dSLBP), which has minimal tertiary structure when not bound to RNA. We show here that phosphorylation of dSLBP dramatically increases binding affinity for stem-loop RNA. The phosphorylated C-terminal tail of dSLBP does not contact RNA. Instead, increased negative charge on the C-terminal tail and stabilization of structural elements by a phosphorylation site within the RNA-binding domain promote more compact conformations that should reduce the entropic barrier to binding histone mRNA.
Crystal structure and encapsulation dynamics of ice II-structured neon hydrate
Authors: Yu Xiaohui , Zhu Jinlong , Du Shiyu , Xu Hongwu , Vogel Sven C. , Han Jiantao , Germann Timothy C. , Zhang Jianzhong , Jin Changqing , Francisco Joseph S. , Zhao Yusheng
Published: July 2014

Significance

Clathrate hydrates have ice-like crystalline structures typically stabled under low-temperature and high-pressure conditions. They are of great importance as potential materials for energy storage and production and carbon dioxide sequestration. Here the first structural refinement data of neon hydrate, to our knowledge, are presented. Both the experimental observations by in situ neutron diffraction and molecular dynamics simulations demonstrate that neon atoms can be enclathrated to form ice II-structured hydrates. The guest Ne atoms occupy the center of ice channels and have substantial freedom of movement owing to the lack of strong bonding between guest molecules and host lattices. The framework of Ne hydrate can be self-stabilized without the encapsulation of guest atoms, which is very special in the hydrate family.
Transformation of the Agrifood Industry in Developing Countries
Authors: Reardon Thomas , Timmer C. Peter
Published: July 2014

Over the past 30 years, the agrifood industry in developing countries has been undergoing rapid transformation in structure and behavior. These changes have been driven by both market forces and government policy, particularly foreign direct investment, and have the potential to affect farmers and consumers; the former via increased incomes and modernized technologies, and the latter via cheaper and safer food. This article examines the transformation of the agrifood industry in developing countries, focusing on the sector’s three segments: retail, wholesale, and processing. It first looks at the factors that drive the transformation of the industry and its procurement systems/supply chains that are shared across the segments. It then considers the “symbioses” among the three segments, highlighting how they reinforce each other and enter preferred supplier relations with one another. It also discusses emerging impacts of the above transformations on farmers as well as small and medium enterprises. Finally, it describes programs that promote linkages for a faster, more integrated, and more inclusive growth path for these transformations over the next decade.
Genetic Animal Models
Authors: Crabbe John C. , Phillips Tamara J.
Published: July 2014

Genetic animal models have a long history of contribution to the understanding of alcohol dependence. Studies have provided insight into genetic contributions to risk and are beginning to be used to suggest better targeted pharmacotherapies. This review discusses how different species and genetic methods have been used to target specific aspects of alcohol dependence. It identifies areas of future promise and those in which more information is needed. It considers how genetic and environmental sources interact to affect risk and treatment response. The review concentrates on alcohol because the majority of data have come from alcohol studies, but it also gives examples of generalization of the alcohol work to other drugs of abuse and identifies some areas where drug-specific factors are important.
The Bourgeoisie, Capitalism, and the Origins of the French Revolution
Authors: Clay Lauren R.
Published: July 2014

When the long-dominant Marxist ‘rise of the bourgeoisie’ paradigm collapsed in the face of the revisionist challenge, scholars largely abandoned questions of capitalism and the bourgeoisie and their relationship to the origins of the Revolution. Research on the transformation of eighteenth-century consumer behaviours and the dramatic expansion of colonial trade, however, has sparked renewed interest in the consequences of these developments for the crisis of the old regime and the revolutionary reinvention of society and politics. Within this emergent scholarship, this essay highlights two trends: those who expand the frame of analysis to consider global economic exchanges, and those who focus in on the perspective of individual consumers. Further, by bringing to light the political mobilization of French business leaders in 1788–89, this chapter proposes that the political choices of the capitalist bourgeoisie may well provide a key to understanding the development of revolutionary politics after all.
Developmental Dyscalculia as a Heterogeneous Disability
Authors: Henik Avishai , Rubinsten Orly , Ashkenazi Sarit
Published: July 2014

This chapter discusses heterogeneous aspects of developmental dyscalculia (DD) in terms of behaviour, cognitive operations, and neural structures. It has been suggested that DD is an isolated learning deficiency, involves a domain-specific deficit (in the capacity to enumerate), and a specific neural deficiency (in the intraparietal sulcus). We present findings that (1) DD involves both domain-specific and domain-general abilities; (2) in many cases behaviours, as well as cognition in those with DD are characterized by deficits in other areas, such as attention or memory and not only as a number sense deficiency; and (3) studies of the neural structures involved in DD reveal areas and mechanisms that hint toward heterogeneous damage. We suggest that similar to other learning disabilities, heterogeneity is the rule, rather than an exception. Accordingly, in order to reach a comprehensive understanding of DD, studies should aim at unravelling the basis for this heterogeneity.
Cognitive Predictors of Mathematical Abilities and Disabilities
Authors: Desoete Annemie
Published: July 2014

The cognitive predictors of mathematical abilities and disabilities/disorders (MD) were investigated. An overview is given of the prediction by early numeracy skills such as Piagetian logical thinking, counting, and number comparison skills. In addition, studies of relationships between language and numeracy in kindergarten and grade 1 are discussed. Moreover, the chapter sought out to extend our knowledge regarding the relationship between motor, visual and visuomotor skills and mathematical abilities and disabilities. Furthermore, the chapter discusses studies of working memory, inhibition, naming speed and inference control as cognitive predictors for mathematical abilities and MD. Finally findings about the sensitivity of number sense for MD are provided.
Number Processing and Arithmetic in Children and Adults with Reading Difficulties
Authors: Göbel Silke M.
Published: July 2014

Basic number processing skills in individuals with reading difficulties (RD) are intact. However, children and adults with RD show clear difficulties in arithmetic, in particular in retrieving known answers from long-term memory (fact retrieval). Fact retrieval deficits are associated with weaknesses in phonological awareness, the ability to segment and manipulate speech sounds. The left angular gyrus has been suggested as a site of neurological overlap between RD and fact retrieval deficits. While there is evidence for an involvement of the angular gyrus in fact retrieval in adults, the evidence for children is less clear. The same genetic risk factors may underlie difficulties in reading and mathematics and cause the high co-morbidity between RD and mathematical difficulties. Implications for interventions are discussed.
Cities and Urbanization in American Political Development
Authors: Dilworth Richardson
Published: July 2014

I suggest in this chapter that the uneasy fit of cities in the American political system (something that has persisted despite the fact that both cities and the American political system, and their relationships to one another, have changed dramatically over the past two centuries) might tell us something interesting about American political development. My suggestion fits into the strain of historical institutionalist research that sees institutional ‘friction’ or ‘intercurrence’ as key to explaining significant change over time. It diverges, however, from the dominant traditions within the study of American urban politics. I provide an overview of these dominant traditions, and I then suggest how viewing cities as ill-fitting elements within American political development might open up new avenues for researching the relationships between cities and American political thought, federalism, and the construction of political roles and identities.
Poisoning the Well, or How Economic Theory Damages Moral Imagination
Authors: Nelson Julie A.
Published: July 2014

Contemporary mainstream economics has widely “poisoned the well” from which people get their ideas about the relationship between economics and ethics. The image of economic life as inherently characterized by self-interest, utility- and profit-maximization, and mechanical controllability has caused many businesspeople, judges, sociologists, philosophers, policymakers, critics of economics, and the public at large to come to tolerate greed and opportunism, or even to expect or encourage them. This chapter raises and discusses a number of counterarguments that might be made to the charge that current dominant professional practice is having negative ethical effects, as well as discussing some examples of the harms inflicted in the areas of law, care work, the environment, and ethics itself.
Understanding and Treating the Psychosocial Consequences of Pregnancy Complications and the Birth of a High-Risk Infant
Authors: Holditch-Davis Diane , Miles Margaret Shandor
Published: July 2014

This chapter examines parental responses to pregnancy complications and having a high-risk infant. Women with high-risk pregnancies have more depressive symptoms, stress, and anxiety than healthy pregnant women. They experience shock, worry, sadness, frustration, anger, guilt, and grief; perform fewer health-promoting behaviors; and have less intense maternal–fetal attachment. Parents also experience emotional distress after the birth of a high-risk infant, including worry about infant survival and outcomes, stress, anxiety, depression, post-traumatic stress, grief, hostility, and powerlessness. Distressed parents perceive their infants more negatively and are less sensitive in interactions than nondistressed parents. Several postnatal interventions have been implemented to ameliorate these negative responses. Overall, the responses of mothers to a high-risk pregnancy or birth of a high-risk infant are remarkably similar. More needs to be known about the effect of the parent’s past history, paternal responses, responses of minorities, experiences of parents of high-risk full-term infants, and interventions to ameliorate negative parental responses.