bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of Plasmodium falciparum Histidine-Rich Protein-2 in Cerebrospinal Spinal Fluid from Cerebral Malaria Patients
Authors: Mikita Kei , Thakur Kiran , Anstey Nicholas M. , Piera Kim A. , Pardo Carlos A. , Weinberg J. Brice , Mukemba Jackson , Florence Salvatore , Mwaikambo Esther D. , Granger Donald L. , Sullivan David J.
Published: July 2014

A cerebrospinal fluid (CSF) biomarker for cerebral malaria (CM) has not been validated. We examined the detection, semiquantification, and clinical use of the Plasmodium falciparum histidine-rich protein-2 (PfHRP-2) as a parasite antigen biomarker for CM. The PfHRP-2 was detected in archival CSF samples from CM patients from Tanzania both by a newly developed sensitive and specific immuno-polymerase chain reaction (72 of 73) and by rapid diagnostic tests (62 of 73). The geometric mean PfHRP-2 CSF concentration was 8.76 ng/mL with no differences in those who survived (9.2 ng/mL), those who died (11.1 ng/mL), and those with neurologic sequelae (10.8 ng/mL). All aparasitemic endemic and nonendemic control samples had undetectable CSF PfHRP-2. In a separate group of 11 matched plasma and CSF cerebral malaria patient samples, the ratio of plasma to CSF PfHRP-2 was 175. The CSF PfHRP-2 reflects elevated plasma PfHRP-2 rather than elevated CM-specific CSF ratios, falling short of a validated biomarker.
The effects of turbulent collision–coalescence on precipitation formation and precipitation-dynamical feedbacks in simulations of stratocumulus and shallow cumulus convection
Authors: Franklin C. N.
Published: July 2014

Abstract. A double moment warm rain scheme that includes the effects of turbulence on droplet collision rates has been implemented in a large-eddy model to investigate the impact of turbulence effects on clouds and precipitation. Simulations of shallow cumulus and stratocumulus show that different precipitation-dynamical feedbacks occur in these regimes when the effects of turbulence are included in the microphysical processes. In both cases inclusion of turbulent microphysics increases precipitation due to a more rapid conversion of cloud water to rain. In the shallow convection case, the greater water loading in the upper cloud levels reduces the buoyancy production of turbulent kinetic energy and the entrainment. The stratocumulus case on the other hand shows a weak positive precipitation feedback, with enhanced rainwater producing greater evaporation, stronger circulations and more turbulence. Sensitivity studies in which the cloud droplet number was varied show that greater number concentrations suppress the stratocumulus precipitation leading to larger liquid water paths. This positive second indirect aerosol effect shows no sensitivity to whether or not the effects of turbulence on droplet collision rates are included. While the sign of the second indirect effect is negative in the shallow convection case whether the effects of turbulence are considered or not, the magnitude of the effect is doubled when the turbulent microphysics are used. It is found that for these two different cloud regimes turbulence has a larger effect than cloud droplet number and the use of a different bulk microphysics scheme on producing rainfall in shallow cumuli. However, for the stratocumulus case examined here, the effects of turbulence on rainfall are not statistically significant and instead it is the cloud droplet number concentration or the choice of bulk microphysics scheme that has the largest control on the rain water.
Microfungi of the Tatra Mts. 6. Fungus-like organisms: Albuginales, Peronosporales and Pythiales
Authors: Mułenko Wiesław , Kozłowska Monika , Bacigálová Kamila , Świderska-Burek Urszula , Wołczańska Agata
Published: July 2014

A list and the distribution of Oomycota species in the Tatra Mts (Western Carpathian Mts) are presented. Revised herbarium vouchers and literature data were used for analysis. Thirty two species of oomycetes on fifty seven plant species were noted in the area, including two species of the order Albuginales (genera: Albugo and Pustula, on nine plant species), 29 species of the order Peronosporales (genera: Bremia, Hyaloperonospora, Peronospora and Plasmopara, on 49 plant species), and one species of the order Pythiales (genus: Myzocytium, on one species of algae). Twenty nine species were collected on the Polish side of the Tatra Mts and ten species were collected on the Slovak side. The oomycetes were collected at 185 localities.
Diversity of yeast-like fungi and their selected properties in bioaerosol premises utility
Authors: Ejdys Elżbieta , Dynowska Maria , Biedunkiewicz Anna , Sucharzewska Ewa
Published: July 2014

A total of 69 isolates of yeasts were recorded in the indoor air of the school buildings: 43 in heated rooms and 26 in unheated rooms. Perfect stages prevailed. Fungi isolated in our study belonged to 39 species. These were mostly monospecific isolates although five two-species isolates were noted. Differences in the properties of physiological characters of fungi isolated in both study seasons were observed. As indoor and outdoor air does not mix during the heating season, a specific substrate for prototrophic, non-fermenting yeastlike fungi forms. Acid production allows fungi to dissolve inorganic compounds in building structures and to release needed microcomponents. Abilities to produce carotenoid pigments are clearly promoted in yeast-like fungi living indoor. This may be related to the accumulation of compounds that are indirect stages in the cycle of biosynthesis of carotenoids or a surplus of oxidizing compounds.
Leccinum variicolor (Basidiomycota, Boletales) in Poland
Authors: Stasińska Małgorzata , Sotek Zofia
Published: July 2014

Leccinum variicolor Watling is widespread but it is a rare species in Poland and some other countries, and is either protected or red-listed. This paper describes the morphology and ecology of L. variicolor as well as its distribution in Poland.
Grazing preference of Ceratophysella sp. 1 (Collembola) for Pseudoperonospora cubensis - fungal pathogen of Cucumis sativus
Authors: Chlebicki Andrzej , Radwański J. M.
Published: July 2014

Grazing preferences of collembolans Ceratophysella sp. 1 were noted. The collembolans feed on the sporangia of Pseudoperonospora cubensis growing on plants Cucumis sativus in greenhouses in Esfahan province in Iran. Sporangia of Pseudoperonospora cubensis were the preferred food of all fungal species noted in the alimental tract of the springtails. All digestive tracts of the springtails contained sporangia of P. cubensis.
RELIGIÃO E CULTURA: UM BREVE ITINERÁRIO DO FIM DO MUNDO ANTIGO AOS DIAS DE KIERKEGAARD
Authors: Gimenes de Paula Marcio
Published: July 2014

Kierkegaard nos mostra, em boa parte de suas obras, sua categórica rejeição em aceitar que a religião cristã pudesse ser reduzida a uma questão de cultura. Mesmo vivendo numa época em que muitos parecem aceitar essa premissa, o filósofo enfrenta inúmeras dificuldades para fazer valer seu posicionamento e, por outro lado, sua proposta parece, ao mesmo tempo, profundamente discutível e polêmica. O cristianismo parece se confundir com a cultura desde seus primórdios e, inclusive, talvez tenha dependido disso para sua sobrevivência até a atualidade. Desse modo, a tese kierkegaardiana de recusa a uma ligação mais efetiva entre cristianismo e cultura não pode ter, em si mesma, um aspecto intolerante ou reacionário? Para investigar tal questão, almejamos analisar aspectos da obra kierkegaardiana e, a partir de um dado recorte, o contexto de implantação do cristianismo no fim do mundo antigo.
A HIPÓTESE DO CONTINUUM DE DARWIN E A DISTRIBUIÇÃO DOS FENÔMENOS MENTAIS
Authors: Octavio de Melo Araújo Arthur
Published: July 2014

Neste trabalho, procuro explorar o significado filosófico da chamada hipótese do continuum de Darwin e a possibilidade de atribuir mente ou mentalidade a criaturas não-humanas: de um lado, temos o chamado problema de ‘distribuição dos fenômenos mentais’ na recente Etologia Cognitiva; e, de outro, o problema filosófico ‘outras mentes’. Assim, o trabalho procurar indicar uma possível ponte conceitual entre problemas em Filosofia da Mente e estudos em Etologia Cognitiva. Esta é, portanto, uma abordagem interdisciplinar entre filosofia e biologia tendo em vista uma concepção ampla de mente ou mentalidade.
¿POBRES Y RICOS DE MUNDO? REPENSANDO LA NOCIÓN HEIDEGGERIANA DE LA ANIMALIDAD
Authors: Neira Hernán , Aurenque Diana
Published: July 2014

Heidegger genera la idea de que el animal es “pobre de mundo”, a diferencia del Dasein, que es “configurador de mundo”. Sobre esta distinción entre animales y el Dasein caben dos hipótesis: si se trata de algo puramente descriptivo, no implica jerarquía de lo humano sobre lo animal. Si, en cambio, en la descripción se mezclan aspecto valóricos o agrega aspectos (no necesariamente explícitos) de dominio de lo humano sobre lo animal, entonces Heidegger restablece algunos rasgos de la metafísica de lo animal, contrariamente a su propósito de cuestionar la metafísica. La consecuencia de ello sería, también, recomponer algunos aspectos de la metafísica humana. ¿Hasta qué punto y por qué exactamente la concepción heideggeriana del ser humano como “Dasein” o “configurador de mundo”, o del animal como un ente “pobre de mundo”, representan un aporte significativo para una investigación que piense los límites y alcances de la relación hombre-animal-mundo?, y, ¿cuáles son algunas de las consecuencias que se deducirían si en la descripción heideggeriana del tema aparecen aspectos normativos no previstos por su mismo autor?
TELA DESCONSTRUCIONISTA: ARQUIVO E MAL DE ARQUIVO A PARTIR DE JACQUES DERRIDA
Authors: Eleonora Nigro Solis Dirce
Published: July 2014

Considerando os vários sentidos da palavra "tela" em português, tela como resultante do entrelaçamento de fios, tela como tecido, tela de cinema ou de televisão, quadro pintado, ou como questão (o assunto, a notícia “em tela”), pretendo trazer à discussão o despojamento de Jacques Derrida ao propor, sob o prisma da desconstrução, o deslocamento do velho conceito de arquivo para uma noção de arquivo aberta a possibilidades imprevisíveis. Para tanto, seu entendimento do que ele chamou de “impressão freudiana”, sua interpretação da pulsão de morte como “mal de arquivo”, nos colocará em contato com uma espécie de revolução “arquiviolítica” nos textos de toda ordem, em especial o texto psicanalítico e as artes.
Sobre la interpretación en psicoanálisis: Ricoeur, Freud y Lacan
Authors: Esteban Peppino Santiago
Published: July 2014

El siguiente trabajo se propone, en primer lugar, contraponer la lectura fi losófi ca de Ricoeur sobre la interpretación en psicoanálisis con algunos desarrollos clave de Freud y Lacan al respecto. Luego, se mostrará desde la obra del fi lósofo esloveno Slavoj Žižek cómo este concepto psicoanalítico puede ser utilizado dentro del marco de la crítica de las ideologías. De esta manera, se intentará determinar y fundamentar, al menos de manera aproximada, si la interpretación en psicoanálisis constituye una exégesis o desciframiento del símbolo, o si la estructura del discurso analítico mismo exige otra concepción que no se agota en una hermenéutica.
El concepto de sujeto en Badiou y Lacan
Authors: Farrán Roque
Published: July 2014

Este artículo es parte de un trabajo de investigación bastante más amplio, que llevó casi cinco años de duración, en el cual nos propusimos una lectura rigurosa como singular del concepto de sujeto en Alain Badiou y Jacques Lacan. En vistas a delimitar claramente el tema de estudio, la pregunta que nos formulamos como punto de partida fue la siguiente: ¿qué lugar (topos) ocupa el concepto de sujeto en la articulación lógica (logos) del pensamento de ambos autores, particularmente en sus dimensiones ontológicas y políticas? Como se podrá apreciar a continuación, dicho trabajo despliega una topología conceptual que a su vez presenta ciertos hitos históricos. Pues es sabido que uno de los temas centrales en torno al cual ha girado la fi losofía política contemporánea ha sido la cuestión del sujeto, y así también, correlativamente, de los saberes y verdades que lo fundamentan (PALTI, 2005; FOUCAULT, 2010). Se ha interrogado por ejemplo ¿cuál puede ser el lugar de este sujeto? ¿Es posible especifi car a priori su existencia? ¿De dónde deriva su estatuto? ¿Se trata de una función trascendental o sustancial, vacía o refl exiva? Estas preguntas responden, en cierta forma, a una concepción de sujeto más bien propia de la metafísica moderna que intentaremos desplazar.
Violação intraescolar de direitos humanos: jogo de espelhos
Authors: Gomes Candido Alberto , Acioli Diogo , Prieto Quezada María Teresa
Published: July 2014

Esta pesquisa exploratória de casos múltiplos analisa as dinâmicas das relações entre estudantes adolescentes em escolas consideradas de elevada violência, pelas quais se constituíam grupos de agressão/proteção, com os seus dominadores e dominados. Os estabelecimentos se configuraram como reflexos de contextos sociais violentos e, ao mesmo tempo, atuavam como laboratórios de violências, onde, a estas eram importadas, ressignificadas e devolvidas à sociedade. Com isso, tornavam-se âmbitos de violação dos direitos humanos. Políticas públicas amplas que desconheçam essa fina tessitura das relações sociais correm o risco de não chegar à intimidade das dinâmicas da violência e, assim, de não alcançar objetivos e metas. Propõem-se alternativas para a superação das violências, nas perspectivas da filosofia e sociologia da educação.
Diversidade cultural, desigualdade e exclusão: um encontro com professores da Educação Básica
Authors: Pavan Ruth
Published: July 2014

Este artigo é fruto da pesquisa financiada pelo CNPq que analisa a compreensão dos professores sobre os processos de exclusão na sociedade e na Educação Básica. O artigo refere-se apenas a professores das séries finais do Ensino Fundamental. No processo de análise, utilizamos teóricos que enfatizam a exclusão e a desigualdade numa perspectiva crítica, ou seja, defendem que elas são frutos das relações sociais assimétricas e desiguais, e não provocadas pelo próprio indivíduo. Para identificar a compreensão dos professores, foram realizadas entrevistas com oito docentes das séries finais do Ensino Fundamental, das diferentes áreas de conhecimento. A análise mostrou que a exclusão/desigualdade, quando percebida, não se refere apenas à questão econômica, mas a questões de raça, crença, geração, gênero e outras. Poucos professores afirmam existir processos de exclusão na escola, mas todos admitem que há processos de exclusão na sociedade. Essa forma de ver os processos de exclusão está relacionada aos processos de formação docente. A formação docente incluiu a discussão da desigualdade apenas na década de 1980 e, bem recentemente, a questão da diversidade cultural e exclusão. Nesse sentido, essa pesquisa contribui para que possamos entender criticamente as respostas dos entrevistados e, principalmente, oferece-nos pistas para qualificar o processo de formação docente.
Garantia de direitos e diálogo com a diversidade no cotidiano escolar da Educação Básica
Authors: Eyng Ana Maria , Ens Romilda Teodora
Published: July 2014

O estudo apresenta uma reflexão sobre as possibilidades de garantia de direitos e diálogo com a diversidade no cotidiano escolar para a efetivação da Educação Básica de qualidade social identificados nas representações dos sujeitos da/na escola. A análise foi realizada  com base na diversidade de traços e nas representações de 489 alunos, 126 pais, 50 professores, 20 gestores e 39 funcionários que circulam e significam o espaço escolar sobre expectativa de direitos, direitos fundamentais e finalidade da educação em 14 escolas públicas de Educação Básica de Curitiba e região metropolitana, sendo todas situadas em locais de grande vulnerabilidade social. As vozes dos sujeitos da escola confirmam e alertam sobre a educação como expectativa de direito e o respeito como direito fundamental, o que mostra a necessidade de políticas educacionais que orientem as propostas de formação inicial e continuada de professores nessa perspectiva.
Earliest Holocene south Greenland ice sheet retreat within its late Holocene extent
Authors: Carlson Anders E. , Winsor Kelsey , Ullman David J. , Brook Edward J. , Rood Dylan H. , Axford Yarrow , LeGrande Allegra N. , Anslow Faron S. , Sinclair Gaylen
Published: July 2014

Early Holocene summer warmth drove dramatic Greenland ice sheet (GIS) retreat. Subsequent insolation‐driven cooling caused GIS margin readvance to late Holocene maxima, from which ice margins are now retreating. We use 10Be surface exposure ages from four locations between 69.4°N and 61.2°N to date when in the early Holocene south to west GIS margins retreated to within these late Holocene maximum extents. We find that this occurred at 11.1 ± 0.2 ka to 10.6 ± 0.5 ka in south Greenland, significantly earlier than previous estimates, and 6.8 ± 0.1 ka to 7.9 ± 0.1 ka in southwest to west Greenland, consistent with existing 10Be ages. At least in south Greenland, these 10Be ages likely provide a minimum constraint for when on a multicentury timescale summer temperatures after the last deglaciation warmed above late Holocene temperatures in the early Holocene. Current south Greenland ice margin retreat suggests that south Greenland may have now warmed to or above earliest Holocene summer temperatures.
Effect of impeller design and power consumption on crystal size distribution
Authors: Rane Chinmay V. , Ekambara Kalekudithi , Joshi Jyeshtharaj B. , Ramkrishna Doraiswami
Published: July 2014

Crystallization processes in a 500 mL stirred tank crystallizer with computational fluid dynamics (CFD) and population balances toward estimating how crystal size distributions (CSDs) are influenced by flow inhomogeneities was explored. The flow pattern and CSD are presented here though extensive phase Doppler particle analyzer measurements and CFD predictions for three different impeller designs (disc turbine, pitched blade turbine, and Propeller) and each rotated at three different speeds (2.5, 5, and10 r/s). As crystallization processes in practice could involve break‐up and aggregation of crystals, some selected break‐up and aggregation kernels are incorporated. Extensive comparison of simulations with experimental data showed consistent trends in the proper quantitative range. An attempt has also been made to develop scaling laws: (a) mean particle size with average power consumption per unit mass and (b) particle‐size distribution with the turbulent energy dissipation distribution. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3596–3613, 2014
Modular Synthesis of Phenanthro[9,10‐c]thiophenes by a Sequence of CH Activation, Suzuki Cross‐Coupling and Photocyclization Reactions
Authors: Schnapperelle Ingo , Bach Thorsten
Published: July 2014

A total number of 15 different 3,4‐diarylthiophenes were synthesized, which bear a chlorine atom in ortho‐position of one of the aryl substituents. One aryl group was introduced by an oxidative cross‐coupling reaction, involving a CH activation at C4(3) of the thiophene core. The other aryl group was in most cases introduced by a Suzuki cross‐coupling reaction, which succeeded the oxidative cross‐coupling step. Photocyclization reactions of the 3,4‐diarylthiophenes were performed in a solvent mixture of benzene and acetonitrile (50:50 v/v) at λ=254 nm and proceeded to the title compounds in yields of 60–82 %. The selectivity of the photocyclization was determined at the ortho‐chloro‐substituted aryl ring by the position of the chlorine substituent. At the other ring, a single regioisomer was observed for phenyl and para‐substituted phenyl groups. For 2‐naphthyl and ortho‐substituted phenyl rings a clear preference was observed in favor of a major regioisomer, while meta‐substitution in the phenyl ring led to a about 1:1 mixture of 5‐ and 7‐substituted phenanthro[9,10‐c]thiophenes. Mechanistically, the photocyclization is likely to occur as a photochemically allowed, conrotatory [(4n+2)π] process accompanied by elimination of HCl. It was shown for two phenanthro[9,10‐c]thiophene products that they can be readily brominated in positions C1 and C3 (74–77 %), which in turn allows for further functionalization at these positions, for example, in the course of halogen–metal exchange and polymerization reactions.
Facile Access to 1H‐Indazoles through Iodobenzene‐Catalyzed C–H Amination under Mild, Transition‐Metal‐Free Conditions
Authors: Kashiwa Mitsuhiro , Sonoda Motohiro , Tanimori Shinji
Published: July 2014

The transition‐metal‐ and halogen‐free synthesis of N‐aryl‐substituted 1H‐indazole and derivatives was accomplished on the basis of the iodobenzene‐catalyzed intramolecular C–H amination of hydrazones under mild conditions. Reactions of hydrazones derived from ketones and hydrazines with a catalytic amount of iodobenzene in the presence of Oxone as an oxidant in trifluoroacetic acid took place to afford 1H‐indazoles in moderate to good yields. A plausible reaction mechanism was described on the basis of the control experiments.
RETHINKING HARDOWN HILL: OUR WESTERNMOST EARLY ANGLO-SAXON CEMETERY?
Authors: Austin Matthew
Published: July 2014

This paper reassesses the early Anglo-Saxon assemblage from Hardown Hill, Dorset. Wingrave excavated the objects in 1916 but apart from his 1931 report, and Evison's 1968 analysis, there has been little subsequent discussion. Despite a lack of human remains, the assemblage has been interpreted as representing an early Anglo-Saxon cemetery – our westernmost burial site by a considerable distance and one that pre-dates the historically attested seventh-century expansion of Wessex. The following typological reclassification and contextual analysis casts serious doubts on a funerary context. Instead, an alternative interpretation is presented that views the assemblage as a useful collection of metalwork, intended to be reforged and recycled, which was presumably deposited for safekeeping and never retrieved. Such a reinterpretation highlights the need for a critical reappraisal of material from older excavations. It also has implications for our understanding of post-Roman Dorset, and for the distribution of fifth- and sixth-century Anglo-Saxon material culture more broadly.
The Southern Bluefin Tuna Dispute Revisited: How Far Have We Come?
Authors: Schiffman Howard S. , MacPhee Briony Patricia
Published: July 2014

The Southern Bluefin Tuna dispute of the late 1990s will long be remembered as one of the most important fishery disputes of all time, influencing both ocean governance and international dispute settlement. This commentary explores the legacy of that dispute with a particular emphasis on the growth and development of the Commission for the Conservation of Southern Bluefin Tuna and how the regime is functioning with the addition of several new members. We will focus also on the specific challenges to the conservation and management of the southern bluefin tuna. This includes biological parameters and the legal and political landscape of global fisheries conservation generally. Finally, we will explore emerging conservation strategies to assist the recovery of this highly valuable fish species.
A fast and reliable LC-MS/MS method for simultaneous quantitation of fluoxetine and mirtazapine in human plasma
Authors: Alegete Pallavi , Kancherla Prasad , Albaseer Saeed S. , Boodida Sathyanarayana
Published: July 2014

A rapid and sensitive ultra-performance liquid chromatographic/tandem mass spectrometric assay (LC-MS/MS) was developed to simultaneously quantify fluoxetine and mirtazapine in human plasma using fluoxetine-D5 and olanzapine as internal standards (IS), respectively.
Fast detection of nitroaromatics using phosphonate pyrene motifs as dual chemosensors
Authors: Venkatramaiah N. , Firmino Ana D. G. , Almeida Paz Filipe A. , Tomé João P. C.
Published: July 2014

A new class of dual fluorescent chemosensors for nitroaromatic compounds (NACs) based on phosphonated pyrene derivatives is reported, showing high selectivity towards trinitrotoluene (TNT).
Palladium catalyzed intramolecular acylcyanation of alkenes using α-iminonitriles
Authors: Rondla Naveen R. , Ogilvie Jodi M. , Pan Zhongda , Douglas Christopher J.
Published: July 2014

Catalytic C–C bond activation of accessible α-iminonitriles enable the first alkene acylcyanation reactionsviaa unimolecular reaction (crossover study).
Characteristics and behaviour of liposomes when incubated with natural bile salt extract: implications for their use as oral drug delivery systems
Authors: Hermida Laura G. , Sabés-Xamaní Manuel , Barnadas-Rodríguez Ramon
Published: July 2014

The use of liposomes for oral administration of drugs and for food applications is based on their ability to preserve entrapped substances and to increase their bioavailability.
Three-body interactions in complex fluids: Virial coefficients from simulation finite-size effects
Authors: Ashton Douglas J. , Wilding Nigel B.
Published: July 2014

A simulation technique is described for quantifying the contribution of three-body interactions to the thermodynamical properties of coarse-grained representations of complex fluids. The method is based on a new approach for determining virial coefficients from the measured volume-dependent asymptote of a certain structural function. By comparing the third virial coefficient B3 for a complex fluid with that of an approximate coarse-grained model described by a pair potential, three body effects can be quantified. The strategy is applicable to both Molecular Dynamics and Monte Carlo simulation. Its utility is illustrated via measurements of three-body effects in models of star polymers and in highly size-asymmetrical colloid-polymer mixtures.
Design of a compact spectrometer for high-flux MeV gamma-ray beams
Authors: Corvan D. J. , Sarri G. , Zepf M.
Published: July 2014

A novel design for a compact gamma-ray spectrometer is presented. The proposed system allows for spectroscopy of high-flux multi-MeV gamma-ray beams with MeV energy resolution in a compact design. In its basic configuration, the spectrometer exploits conversion of gamma-rays into electrons via Compton scattering in a low-Z material. The scattered electron population is then spectrally resolved using a magnetic spectrometer. The detector is shown to be effective for gamma-ray energies between 3 and 20 MeV. The main properties of the spectrometer are confirmed by Monte Carlo simulations.
Impact of process temperature on GaSb metal-oxide-semiconductor interface properties fabricated by ex-situ process
Authors: Yokoyama Masafumi , Asakura Yuji , Yokoyama Haruki , Takenaka Mitsuru , Takagi Shinichi
Published: July 2014

We have studied the impact of process temperature on interface properties of GaSb metal-oxide-semiconductor (MOS) structures fabricated by an ex-situ atomic-layer-deposition (ALD) process. We have found that the ALD temperature strongly affects the Al2O3/GaSb MOS interface properties. The Al2O3/GaSb MOS interfaces fabricated at the low ALD temperature of 150 °C have the minimum interface-trap density (Dit) of ∼4.5 × 1013 cm−2 eV−1. We have also found that the post-metalization annealing at temperature higher than 200 °C degrades the Al2O3/GaSb MOS interface properties. The low-temperature process is preferable in fabricating GaSb MOS interfaces in the ex-situ ALD process to avoid the high-temperature-induced degradations.
Evolution of ferroelectricity in tetrathiafulvalene-p-chloranil as a function of pressure and temperature
Authors: Dengl Armin , Beyer Rebecca , Peterseim Tobias , Ivek Tomislav , Untereiner Gabriele , Dressel Martin
Published: July 2014

The neutral-to-ionic phase transition in the mixed-stack charge-transfer complex tetrathiafulvalene-p-chloranil (TTF-CA) has been studied by pressure-dependent infrared spectroscopy up to p = 11 kbar and down to low temperatures, T = 10 K. By tracking the C=O antisymmetric stretching mode of CA molecules, we accurately determine the ionicity of TTF-CA in the pressure-temperature phase diagram. At any point, the TTF-CA crystal bears only a single ionicity; there is no coexistence region or an exotic high-pressure phase. Our findings shed new light on the role of electron-phonon interaction in the neutral-ionic transition.
High-pressure study of isoviolanthrone by Raman spectroscopy
Authors: Zhao Xiao-Miao , Huang Qiao-Wei , Zhang Jiang , Zhong Guo-Hua , Lin Hai-Qing , Chen Xiao-Jia
Published: July 2014

Vibrational properties of isoviolanthrone are investigated by Raman scattering at pressures up to 30.5 GPa and room temperature. A complete characterization of phonon spectra under pressure is given for this material. The onset of a phase transition at 11.0 GPa and the formation of a new phase above 13.8 GPa are identified from both the frequency shifts and the changes in the full width half maxima of the intra- and internal modes. The transition is proposed to result from the changes of intra- and intermolecular bonding. The tendencies of the intensity ratios with pressure are in good agreement with the pressure dependence of the resistance at room temperature, indicating that the phase transition may be an electronic origin. The absence of the changes in the lattice modes indicates that the observed phase transition is probably a result of the structural distortions or reorganizations. The reversible character of the transition upon compression and decompression is determined in the entire pressure region studied.
Canard-like phenomena in piecewise-smooth Van der Pol systems
Authors: Roberts Andrew , Gendinning Paul
Published: July 2014

We show that a nonlinear, piecewise-smooth, planar dynamical system can exhibit canard phenomena. Canard phenomena in nonlinear, piecewise-smooth systems can be qualitatively more similar to the phenomena in smooth systems than piecewise-linear systems, since the nonlinearity allows for canards to transition from small cycles to canards “with heads.” The canards are born of a bifurcation that occurs as the slow-nullcline coincides with the splitting manifold. However, there are conditions under which this bifurcation leads to a phenomenon called super-explosion, the instantaneous transition from a globally attracting periodic orbit to relaxations oscillations. Also, we demonstrate that the bifurcation—whether leading to canards or super-explosion—can be subcritical.
Experiments and theory on parametric instabilities excited in HF heating experiments at HAARP
Authors: Kuo Spencer , Snyder Arnold , Lee M. C.
Published: July 2014

Parametric instabilities excited by O-mode HF heater and the induced ionospheric modification were explored via HAARP digisonde operated in a fast mode. The impact of excited Langmuir waves and upper hybrid waves on the ionosphere are manifested by bumps in the virtual spread, which expand the ionogram echoes upward as much as 140 km and the downward range spread of the sounding echoes, which exceeds 50 km over a significant frequency range. The theory of parametric instabilities is presented. The theory identifies the ionogram bump located between the 3.2 MHz heater frequency and the upper hybrid resonance frequency and the bump below the upper hybrid resonance frequency to be associated with the Langmuir and upper hybrid instabilities, respectively. The Langmuir bump is located close to the upper hybrid resonance frequency, rather than to the heater frequency, consistent with the theory. Each bump in the virtual height spread of the ionogram is similar to the cusp occurring in daytime ionograms at the E-F2 layer transition, indicating that there is a small ledge in the density profile similar to E-F2 layer transitions. The experimental results also show that the strong impact of the upper hybrid instability on the ionosphere can suppress the Langmuir instability.
Buffer transport mechanisms in intentionally carbon doped GaN heterojunction field effect transistors
Authors: Uren Michael J. , Cäsar Markus , Gajda Mark A. , Kuball Martin
Published: July 2014

Temperature dependent pulsed and ramped substrate bias measurements are used to develop a detailed understanding of the vertical carrier transport in the buffer layers in a carbon doped GaN power heterojunction field effect transistor. Carbon doped GaN and multiple layers of AlGaN alloy are used in these devices to deliver an insulating and strain relieved buffer with high breakdown voltage capability. However, understanding of the detailed physical mechanism for its operation is still lacking. At the lowest electric fields (<10 MV/m), charge redistribution within the C doped layer is shown to occur by hole conduction in the valence band with activation energy 0.86 eV. At higher fields, leakage between the two-dimensional electron gas and the buffer dominates occurring by a Poole-Frenkel mechanism with activation energy ∼0.65 eV, presumably along threading dislocations. At higher fields still, the strain relief buffer starts to conduct by a field dependent process. Balancing the onset of these leakage mechanisms is essential to allow the build-up of positive rather than negative space charge, and thus minimize bulk-related current-collapse in these devices.
Band-selective shaped pulse for high fidelity quantum control in diamond
Authors: Chang Yan-Chun , Xing Jian , Zhang Fei-Hao , Liu Gang-Qin , Jiang Qian-Qing , Li Wu-Xia , Gu Chang-Zhi , Long Gui-Lu , Pan Xin-Yu
Published: July 2014

High fidelity quantum control of qubits is crucially important for realistic quantum computing, and it becomes more challenging when there are inevitable interactions between qubits. We introduce a band-selective shaped pulse, refocusing BURP (REBURP) pulse, to cope with the problems. The electron spin of nitrogen-vacancy centers in diamond is flipped with high fidelity by the REBURP pulse. In contrast with traditional rectangular pulses, the shaped pulse has almost equal excitation effect in a sharply edged region (in frequency domain). So the three sublevels of host 14N nuclear spin can be flipped accurately simultaneously, while unwanted excitations of other sublevels (e.g., of a nearby 13C nuclear spin) is well suppressed. Our scheme can be used for various applications such as quantum metrology, quantum sensing, and quantum information process.
Decoherence suppression combining quantum uncollapsing and dynamical decoupling
Authors: Xu K. , LinPeng X. Y. , Wang Z. L.
Published: July 2014

We demonstrate a protocol, that combines quantum uncollapsing and dynamical decoupling, to protect the quantum state stored in a qubit against decoherence errors. The protocol can simultaneously suppress the two kinds of decoherence processes: the energy relaxation and the low-frequency noise induced dephasing. We present the analytical derivation and numerical simulations in detail. We also provide a preliminary experimental test in superconducting phase qubits, using the process fidelity to calibrate the performance of the protocol. Our results suggest that the protocol can be effective against errors due to both energy relaxation and the low-frequency dephasing noise, except at a reduced probability of success.
Polar nanoregions of Ca0.28Ba0.72Nb2O6 probed by second harmonic generation and Raman spectroscopy at high pressure
Authors: Ruiz-Fuertes J. , Bayarjargal L. , Winkler B. , Burianek M. , Mühlberg M.
Published: July 2014

The pressure-induced ferroelectric phase transition of calcium barium niobate Ca0.28Ba0.72Nb2O6 is studied by second harmonic generation (SHG) and Raman spectroscopy. We observe the ferroelectric to paraelectric phase transition at Pc = 4 GPa and evidence for two additional local changes at 8.5 and 11.5 GPa that are interpreted as the characteristic intermediate P* and the Burns pressure PB of a relaxor phase. The pressure dependence of the SHG intensity has a Landau critical exponent of γ = 1.3 between 4 and 8.5 GPa, indicating the presence of static polar nanoregions. At higher pressures, from 8.5 to 11.5 GPa, these nanoregions become dynamic, with γ = 2.4, and disappear at 11.5 GPa. The polar nanoregions appear when only one of the two non-equivalent octahedral positions of Nb is centrosymmetric. A Landau exponent of γ = 1 above 11.5 GPa together with a change in the compression mechanism indicates that the system completes a phase transformation to a centrosymmetric space group and the polar nanoregions vanish.
Tunable microlens actuated via a thermoelectrically driven liquid heat engine
Authors: Ashtiani Alireza Ousati , Jiang Hongrui
Published: July 2014

We have developed a thermally actuated liquid microlens. An embedded thermoelectric element is used to actuate the liquid based heat engine. A closed-loop system is harnessed to drive and stabilize the temperature of the heat engine. Direct contact between the thermoelectric device and the water results in greatly improved, sub-second thermal rise time (0.8 s). The water based heat engine reacts to the variation in the temperature via expansion and contraction. In turn, the shape of a pinned water-oil meniscus at a lens aperture is deformed in response to the net volume change in the water, creating a tunable microlens. A method to fabricate microfluidic devices with relatively high thickness (250–750 μm) and large length-to-depth aspect ratio (280:1) was developed and used in the process. After fabrication and thermal calibration, optical characteristic of the microlens was assessed. Back focal length of the microlens was shown to vary continuously from −19.6 mm to −6.5 mm as the temperature increased from 5 °C to 35 °C. A thin film air was further introduced to insulate the heat engine from the substrate to protect the microlens area from the temperature fluctuation of the heat engine, thus preventing the change of the refractive indices and thermally induced aberrations. Wavefront aberration measurement was conducted. Surface profile of the microlens was mapped and found to have a conical shape. Both 3-dimensional and 1-dimensional thermal models for the device structure were developed and thermal simulation of the device was performed.
Clean surface processing of rubrene single crystal immersed in ionic liquid by using frequency modulation atomic force microscopy
Authors: Yokota Yasuyuki , Hara Hisaya , Morino Yusuke , Bando Ken-ichi , Imanishi Akihito , Uemura Takafumi , Takeya Jun , Fukui Ken-ichi
Published: July 2014

Surface processing of a rubrene single crystal immersed in ionic liquids is valuable for further development of low voltage transistors operated by an electric double layer. We performed a precise and clean surface processing based on the tip-induced dissolution of rubrene molecules at the ionic liquid/rubrene single crystal interfaces by using frequency modulation atomic force microscopy. Molecular resolution imaging revealed that the tip-induced dissolution proceeded via metastable low density states derived from the anisotropic intermolecular interactions within the crystal structure.
Micro-magnetic imprinting of high field gradient magnetic flux sources
Authors: Dempsey N. M. , Le Roy D. , Marelli-Mathevon H. , Shaw Gorky , Dias A. , Kramer R. B. G. , Viet Cuong Le , Kustov M. , Zanini L. F. , Villard C. , Hasselbach K. , Tomba C. , Dumas-Bouchiat F.
Published: July 2014

We report here on the fabrication of hard magnetic powder based micro-flux sources using micro-patterned hard magnetic films as templates or master structures. The micro-magnetic imprinting (μMI) process is simple and the constituent materials of the final structures, commercial hard magnetic powders and polymer, are inexpensive. The structures may be transparent, and either flexible or rigid, depending on the choice of polymer matrix used. The peak-to-peak intensity of the z-component of the stray magnetic field measured above a test μMI structure made with spherical NdFeB particles of average particle size 16 μm is in good agreement with simulated field values (150 mT at 5 μm). Simulations indicate magnetic field gradients of up to 5 × 105 T/m at the surface of such μMI structures. The trapping of cells functionalised with superparamagnetic beads by these structures has been demonstrated. The μMI fabrication technique has much potential for the development of high field gradient magnetic flux sources for applications in biology and beyond.
Linear-like dielectric behavior and low energy loss achieved in poly(ethyl methacrylate) modified poly(vinylidene-co-trifluoroethylene)
Authors: Li Junjie , Gong Honghong , Yang Qi , Xie Yunchuan , Yang Lanjun , Zhang Zhicheng
Published: July 2014

To realize linear-like dielectric characteristics in normal ferroelectric poly(vinylidene-co-trifluoroethylene) (P(VDF-TrFE)), poly(ethyl methacrylate) (PEMA) was grafted onto poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene) as side chains. The introduction of rigid PEMA segments resulted in the decreased crystallinity, crystal and ferroelectric domain size. As a result, reduced dielectric loss and improved modulus, therefore enhanced breakdown strength was obtained in the graft copolymers. Moreover, low energy loss (about 16.6%) and relatively high energy density (19.3 J cm−3) under high electric field (675 MV m−1) was achieved since the hysteresis induced by the ferroelectric relaxation of P(VDF-TrFE) has been completely eliminated.
Ultrafast crystalline-to-amorphous phase transition in Ge2Sb2Te5 chalcogenide alloy thin film using single-shot imaging spectroscopy
Authors: Takeda Jun , Oba Wataru , Minami Yasuo , Saiki Toshiharu , Katayama Ikufumi
Published: July 2014

We have observed an irreversible ultrafast crystalline-to-amorphous phase transition in Ge2Sb2Te5 chalcogenide alloy thin film using broadband single-shot imaging spectroscopy. The absorbance change that accompanied the ultrafast amorphization was measured via single-shot detection even for laser fluences above the critical value, where a permanent amorphized mark was formed. The observed rise time to reach the amorphization was found to be ∼130–200 fs, which was in good agreement with the half period of the A1 phonon frequency in the octahedral GeTe6 structure. This result strongly suggests that the ultrafast amorphization can be attributed to the rearrangement of Ge atoms from an octahedral structure to a tetrahedral structure. Finally, based on the dependence of the absorbance change on the laser fluence, the stability of the photoinduced amorphous phase is discussed.
Multiple types of motives don't multiply the motivation of West Point cadets
Authors: Wrzesniewski Amy , Schwartz Barry , Cong Xiangyu , Kane Michael , Omar Audrey , Kolditz Thomas
Published: July 2014

Significance

Virtually any sustained, effortful activity can be motivated by factors internal to the activity (e.g., scientists pursuing discoveries) or instrumental to it (e.g., scientists pursuing promotions or status). Research in economics and psychology suggests that instrumental motives (often called “extrinsic motives”) undermine the positive impact of internal motives (often called “intrinsic motives”). However, despite 40 y of research, mostly using laboratory-based manipulations, the effect of instrumental motives on the impact of internal motives remains controversial, and naturalistic, long-term tests of its existence are lacking. We show that holding both internal and instrumental motives for attending West Point harms outcomes associated with persistence and performance quality in a sample of over 10,000 cadets over periods spanning up to 14 y.
Both protein dynamics and ligand concentration can shift the binding mechanism between conformational selection and induced fit
Authors: Greives Nicholas , Zhou Huan-Xiang
Published: July 2014

Significance

Mechanisms of protein–ligand binding have long generated interest in wide circles, including enzyme catalysis, receptor function, and drug design. This study reconciles some of the conflicting views. Using simulations of a model protein–ligand system, we demonstrate that neither conformational selection (CS) nor induced fit (IF) is the sole mechanism governing protein–ligand binding. Instead, both intrinsic and extrinsic factors can shift the binding mechanism between CS and IF. CS dominates when both protein conformational transition rate and ligand concentration are low. With the increase of either factor, the binding mechanism shifts to IF. The rigorous theoretical framework established here can guide experiments and simulations in determining the fraction of binding events achieved via either CS or IF.
Positron emission tomography probe demonstrates a striking concentration of ribose salvage in the liver
Authors: Clark Peter M. , Flores Graciela , Evdokimov Nikolai M. , McCracken Melissa N. , Chai Timothy , Nair-Gill Evan , O’Mahony Fiona , Beaven Simon W. , Faull Kym F. , Phelps Michael E. , Jung Michael E. , Witte Owen N.
Published: July 2014

Significance

The saccharide ribose is naturally present in food and circulates in the blood. Previous studies suggest that cells internalize ribose directly from the extracellular space, but how, why, and where this occurs in the body are not well understood. Here, we developed a new PET probe to monitor this process in vivo. Using this probe and [
14
C]ribose, we show that ribose salvage is concentrated in the liver. We identify that solute carrier family 2, member 2 is one of potentially several ribose transporters. We demonstrate that ribose salvage is down-regulated during metabolic syndrome. This work raises the possibility that ribose is an important sugar for whole-body metabolism.
COSMOS: Python library for massively parallel workflows
Authors: Gafni Erik , Luquette Lovelace J. , Lancaster Alex K. , Hawkins Jared B. , Jung Jae-Yoon , Souilmi Yassine , Wall Dennis P. , Tonellato Peter J.
Published: July 2014

Summary: Efficient workflows to shepherd clinically generated genomic data through the multiple stages of a next-generation sequencing pipeline are of critical importance in translational biomedical science. Here we present COSMOS, a Python library for workflow management that allows formal description of pipelines and partitioning of jobs. In addition, it includes a user interface for tracking the progress of jobs, abstraction of the queuing system and fine-grained control over the workflow. Workflows can be created on traditional computing clusters as well as cloud-based services.

Availability and implementation: Source code is available for academic non-commercial research purposes. Links to code and documentation are provided at http://lpm.hms.harvard.edu and http://wall-lab.stanford.edu .

Contact:  dpwall@stanford.edu or peter_tonellato@hms.harvard.edu .

Supplementary information : Supplementary data are available at Bioinformatics online.
Detection of Caspase Activity Using Antibody-Based Techniques
Authors: McStay Gavin P. , Green Douglas R.
Published: July 2014

A number of antibodies have been generated that recognize caspases from mammalian model organisms. These include antibodies that recognize specific caspase pro-forms and others that bind caspase cleavage fragments. These antibodies are excellent reagents for identifying which executioner caspases have been activated following application or induction of a specific apoptotic stimulus. This approach is more difficult to use with initiator caspases, however, because cleavage does not necessarily correlate with caspase activation. In this protocol, cultured cells are treated with a proapoptotic stimulus, and then protein lysates are prepared from the treated cells. The proteins are then separated by gel electrophoresis and transferred to a suitable membrane. The fragment-specific antibodies that recognize executioner caspases are used in a western analysis to determine the extent of activation and to aid in identifying which caspases have been activated.