bluuebunny/crossref_metadata_2025 huggingface dataset:
Active-layer thickness estimation from X-band SAR backscatter intensity
Authors: Widhalm Barbara , Bartsch Annett , Leibman Marina , Khomutov Artem
Published: February 2017

Abstract. The active layer above the permafrost, which seasonally thaws during summer, is an important parameter for monitoring the state of permafrost. Its thickness is typically measured locally, but a range of methods which utilize information from satellite data exist. Mostly, the normalized difference vegetation index (NDVI) obtained from optical satellite data is used as a proxy. The applicability has been demonstrated mostly for shallow depths of active-layer thickness (ALT) below approximately 70 cm. Some permafrost areas including central Yamal are, however, characterized by larger ALT. Surface properties including vegetation structure are also represented by microwave backscatter intensity. So far, the potential of such data for estimating ALT has not been explored. We therefore investigated the relationship between ALT and X-band synthetic aperture radar (SAR) backscatter of TerraSAR-X (averages for 10  ×  10 m window) in order to examine the possibility of delineating ALT with continuous and larger spatial coverage in this area and compare it to the already-established method of using NDVI from Landsat (30 m). Our results show that the mutual dependency of ALT and TerraSAR-X backscatter on land cover types suggests a connection of both parameters. A range of 5 dB can be observed for an ALT range of 100 cm (40–140 cm), and an R2 of 0.66 has been determined over the calibration sites. An increase of ALT with increasing backscatter can be determined. The root mean square error (RMSE) over a comparably heterogeneous validation site with maximum ALT of  >  150 cm is 20 cm. Deviations are larger for measurement locations with mixed vegetation types (especially partial coverage by cryptogam crust) with respect to the spatial resolution of the satellite data.
An error reduction algorithm to improve lidar turbulence estimates for wind energy
Authors: Newman Jennifer F. , Clifton Andrew
Published: February 2017

Abstract. Remote-sensing devices such as lidars are currently being investigated as alternatives to cup anemometers on meteorological towers for the measurement of wind speed and direction. Although lidars can measure mean wind speeds at heights spanning an entire turbine rotor disk and can be easily moved from one location to another, they measure different values of turbulence than an instrument on a tower. Current methods for improving lidar turbulence estimates include the use of analytical turbulence models and expensive scanning lidars. While these methods provide accurate results in a research setting, they cannot be easily applied to smaller, vertically profiling lidars in locations where high-resolution sonic anemometer data are not available. Thus, there is clearly a need for a turbulence error reduction model that is simpler and more easily applicable to lidars that are used in the wind energy industry. In this work, a new turbulence error reduction algorithm for lidars is described. The Lidar Turbulence Error Reduction Algorithm, L-TERRA, can be applied using only data from a stand-alone vertically profiling lidar and requires minimal training with meteorological tower data. The basis of L-TERRA is a series of physics-based corrections that are applied to the lidar data to mitigate errors from instrument noise, volume averaging, and variance contamination. These corrections are applied in conjunction with a trained machine-learning model to improve turbulence estimates from a vertically profiling WINDCUBE v2 lidar. The lessons learned from creating the L-TERRA model for a WINDCUBE v2 lidar can also be applied to other lidar devices. L-TERRA was tested on data from two sites in the Southern Plains region of the United States. The physics-based corrections in L-TERRA brought regression line slopes much closer to 1 at both sites and significantly reduced the sensitivity of lidar turbulence errors to atmospheric stability. The accuracy of machine-learning methods in L-TERRA was highly dependent on the input variables and training dataset used, suggesting that machine learning may not be the best technique for reducing lidar turbulence intensity (TI) error. Future work will include the use of a lidar simulator to better understand how different factors affect lidar turbulence error and to determine how these errors can be reduced using information from a stand-alone lidar.
For Whose Eyes Only?: China's Journalistic Internal Reference and Its Legal and Political Implications
Authors: Tang Yong
Published: February 2017

Journalistic internal reference is a highly secretive system that allows reporters in China to submit investigative journalism exclusively to party and government leaders. The article explores how the system was established and how it operates in today's communication, legal, and political environments. In particular, the article investigates the method's legal and political implications, with a special focus on examining the conflicts the concept and practice of journalistic internal reports may have with China's first freedom of information law, and the unfairness secretive journalism may bring to enforcement of libel law. Furthermore, the article identifies news media internal reports' failure to hold party and government accountable and its inappropriate role as think tank for senior party and government leaders. Despite recent party and government efforts to revitalize the system, the article proposes an eventual elimination of the century-long practice of sealing newsworthy information. The article argues that phasing out journalistic internal reference would create a better international image for the Chinese state, ensure more transparent and accountable governance, facilitate freer flow of information, guarantee better exercise of people's right to know, and help to establish more credible media institutions.
Chintrepreneurship – The China-way of Entrepreneurship Government Intervention, Seedling Approach – A Network-based Model of Entrepreneurship
Authors: Zhao Jiangning , Zhang Bin
Published: February 2017

The development of entrepreneurship in China is coined in this paper as the ‘Chintrepreneurship’, namely, theChina-way of entrepreneurship, which is defined synthetically as an integral result of ideological transformation,industrial institutionalization and privatization, and technological transition from imitation and innovation. From anevolutionary perspective, China-way of entrepreneurship is resulted from the three-staged economic reformation.From a dialectic perspective, government intervention is not only a driver but also an obstacle to the formation ofChina-way of entrepreneurship, which is outlined as a compounded effect of dual-track policy, financial policy, FDIpolicy, science, technology, and innovation policy, education and human capital policy. As an exploratory study andrelying on an in-depth and extensive literature review, on-site observations and thousands of interviews, this paperendeavors to establish a theoretical framework, to contour the taxonomy and the four constraints, and to distinguishthe formational mechanism of China-way of entrepreneurship from the previously defined ones. Theoretically, thispaper proposes a need for a paradigm shift from polarized (Washington Consensus) to de-polarized (BeijingConsensus), and argues that, the network-based framework (aka: the neo-classical economics) fits to rationalize thepeculiarity and mechanism of China-way of entrepreneurship, uniquely incubated from the politically autocratic,bureaucratic and cronyism oriented social and institutional systems. This paper concludes that entrepreneurship doesexist in China, and that, government intervention and seedling approach serve as strategic and exogenous forces,while imitation and low marginal price act as tactical and endogenous factors – together, they constitute thedevelopmental mechanism of CHINTREPRENEURSHIP, in parallel with economic transition, from traditionally theglobal production networks (GPNs) to presently the global production and trade networks (GPTNs), frommanufacturing-based to service and consumption oriented. From the perspective of Darwin’s ‘survival of the fittest’,criticism is definitely needed, in order to legitimize the theory of CHINTREPRENEURSHIP.
Assessing Miles and Snow Typology through the Lens of Managerial Discretion: How National-Level Discretion Impact Firms Strategic Orientation
Authors: Haj Youssef Moustafa Salman , Christodoulou Ioannis
Published: February 2017

Studies on the implications of managerial discretion have mainly focused on the firm, executive or industry levelattributes. Little work has tackled the national-level aspect of this construct and its potential implication on firmstrategies. We seek to theoretically establish an association between the construct of managerial discretion and firmstrategic orientation from a national-level. Our theoretical analysis strongly suggests that the degree of managerialdiscretion available to executives in each country could have a strong influence on companies’ competitive strategy.We contribute to the strategic management field and the discretion literature by uncovering new national-levelimplications.
Spatial Mapping of Carbon Stock in Riverine Mangroves Along Amanzule River in the Ellembelle District of Ghana
Authors: Yevugah Lily L. , Osei Jnr. Edward M. , Ayer John , Osei Nti. Joshua
Published: February 2017

Compared to other wetland ecosystems mangroves are well known for their numerous ecosystem services, especially carbon pool. In Ghana, there is limited information on the sequestered carbon in mangroves. There is increasing interest on national climate change mitigation and adaptation plans in mangroves in developing nations, and Ellembelle in the Western Region of Ghana is of no exception. Ellembelle is one of the areas with little information on the size and variation of mangrove carbon stock which needs to be addressed. This research is aimed at determining the carbon stock from the carbon sequestered in mangrove and the areal extent in mangrove forest using remote sensing and allometric equation. The ecosystem carbon density estimate for the mangrove forest was weighted based on their spatial distribution across the landscape to yield a total carbon stock of for the Ellembelle mangrove forest. The error obtained from the 95% Confidence Interval was + 1.53%, which is within the acceptable levels of uncertainty based on the Monte Carlo Analysis. The overall carbon estimated for 2015 based on the area for mangrove (374.49 ha) was 1.550Mt with an uncertainty of +57.125Kt indicating a high amount of carbon sequestered in mangroves.
Estimation of the Depth of Major Subsurface Discontinuities Beneath the Mount Cameroon Region, Central Africa, Based on New and Existing Gravity Data Analysis
Authors: Victor KENFACK Jean , Joseph Kamguia , Armand Kagou Dongmo , Lucas Kengni , Bertrand Mbog Michel , Bernard Tassongwa , Charles Tabod Tabod
Published: February 2017

The Mount Cameroon region is investigated using 2-D spectral analysis of the gravity data, in order to determine the depth of subsurface interfaces beneath the region. New gravity data are combined to existing ones to determine the depth of the major subsurface discontinuities throughout the region. Depths are established from the slope of the log-power radial spectrum et the lower end of the wave number band. Three major subsurface density discontinuities are determined beneath the Mount Cameroon: (1) 0.41 ±  0.02 km, (2) 1.26 ± 0.06 km, (3) 4.73 ± 0.24 km. This result has the best precision comparing with the those from the former Bouguer anomaly where the major subsurface discontinuities obtained are: (1) 0.48 ± 0.02 km for the first layer, 1.81 ± 0.09 km for the second and 6.87 ± 0.34 km for the third. This difference is probabely due to the densification of gravity data.  The knowledge on the depth of different interfaces in the crust is very important in the reconstitution of the earth history. These results will the support of prospective investigations throughout this region.
Excessive Debt or Excess Savings -- Transition Countries Sovereign Bond Spread Assessment
Authors: Petkov Boris T.
Published: February 2017

We study the sovereign yield spreads determinants in transition – Central and Eastern Europe (CEE) and Caucasus and Central Asia (CCA) -- countries and try to provide an answer to the key question: was the narrowing of the spreads and their compression a result of improvement of CEECCA countries sovereign’s macroeconomic policy (implemented in early to mid 2000s), or was it due to global excess liquidity provision? If better domestic macroeconomic policy efforts and solid reforms implemented in this period have led to: i) improvement in sovereign debt management e.g., by increasing the average debt portfolio duration and reducing the stock of FOREX debt; ii) development of domestic financial markets with enlargement of the investor’s base and enhancement of the risk management techniques; iii) continuing financial liberalization; iv) sustainable fiscal adjustment, reserve accumulation and price stability; and v) adoption of the most conductive to prosperity institutional structure, then it would be expected that any tighter monetary policy environment in the developed economies should have only a tiny effect on spreads.The models are estimated on an individual basis -- country by country -- using a framework allowing for fractionally integrated variables (ARDL) as well as, by utilising panel data (cross-sectional-time-series) estimation whenever data availability allows.We utilise daily data over the period 2006-2012 and quarterly data over the period 2002-2011. These are the periods for which meaningful comparable data are available for Bulgaria, Croatia, Hungary, Kazakhstan, Poland, Russia, Serbia, and Ukraine (in various combinations).We are careful not to attempt to split the sample into (say two) potential segments for comparison of “normal” versus “crises” period estimates (as customary) as since 2002 / 2003 the transition economies have started to experience the powerful financial effect generated by the excess global liquidity, i.e., the entire period under consideration is constituted by two phases characterised by: i) excess liquidity (2002-2008); and, ii) the Great Depression Mark II (2008 – to present).
Spectrophotometric Methods for Simultaneous Determination of Sofosbuvir and Ledipasvir (HARVONI Tablet): Comparative Study with Two Generic Products
Authors: Abo-Talib Nisreen F , El-Ghobashy Mohamed R , Tammam Marwa H
Published: February 2017

Sofosbuvir and ledipasvir are the first drugs in a combination pill to treat chronic hepatitis C virus. Simple, sensitive, and rapid spectrophotometric methods are presented for the determination of sofosbuvir and ledipasvir in their combined dosage form. These methods were based on direct measurement of ledipasvir at 333 nm (due to the lack of interference of sofosbuvir) over a concentration range of 4.0–14.0 µg/mL, with a mean recovery of 100.78 ± 0.64%. Sofosbuvir was determined, without prior separation, by third-derivative values at 281 nm; derivative ratio values at 265.8 nm utilizing 5.0 µg/mL ledipasvir as a divisor; the ratio difference method using values at 270 and 250 nm using 5.0 µg/mL ledipasvir as a divisor; and the ratio subtraction method using values at 261 nm. These methods were found to be linear for sofosbuvir over a concentration range of 5.0–35.0 µg/mL. The suggested methods were validated according to International Conference on Harmonization guidelines. Statistical analysis of the results showed no significant difference between the proposed methods and the manufacturer's LC method of determination with respect to accuracy and precision. These methods were used to compare the equivalence of an innovator drug dosage form and two generic drug dosage forms of the same strength.
Empoasca papayae Oman, 1937 (Hemiptera: Cicadellidae) the simultaneous vector of phytoplasmas and rickettsia associated with “Bunchy Top Symptom” in Cuba
Authors: Acosta Karel Ismar , Zamora Loidy , Piñol Berta , Quiñones Madelaine Luisa , Ramos Pedro Luis , Luis Maritza , Leyva-López Norma Elena , Arocha Yaima
Published: February 2017

Ensayos de transmisión mostraron desarrollo de síntomas típicos de BTS en todas las plantas de papaya después de tres meses de post-inoculadas con Empoasca papayae. El fitoplasma identificado en 28 de 45 las plantas inoculadas, presentó, en secuencia de ADN ribosomal 16S, un 99,9% igual al identificado en plantas de campo y con las detectadas previamente en E. papayae en Cuba. Todos son miembros del subgrupo de fitoplasma 16SrI-B. Una rickettsia se identificó en 41 de las 45 plantas inoculadas. Su secuencia parcial del gen sdhA mostró un 100% de identidad con la rickettsia identificada en plantas de campo, E. papayae y las previamente publicadas. Los resultados confirmaron la habilidad de E. papayae para transmitir simultáneamente el fitoplasma y la rickettsia.

Transmission trials showed typical BTS symptoms developed in all papaya plants after three months post-inoculated with Empoasca papayae. The BTS phytoplasma was identified in 28 out of 45 inoculated papayas, whose partial 16S rDNA sequence was 99.9% identical to those of the phytoplasma identified in the field-collected papayas, and that previously detected in E. papayae in Cuba. These are all members of the phytoplasma subgroup 16SrI-B. A rickettsia was identified in 41 out of 45 inoculated papayas. It showed a 100% of identity of its partial sdhA sequence to those from the field-collected papayas, E. papayae and the rickettsia previously identified. Results confirmed the ability of E. papayae to simultaneously transmit the BTS phytoplasma and the rickettsia pathogen.
Eksemplets magt
Authors: Stage Lilian
Published: February 2017

No abstract.
Koncernspecifik brancheordbog med særligt henblik på teknisk engelsk: Prækonceptionelle overvejelser og koncept
Authors: Pedersen Jette
Published: February 2017

No abstract.
Text condensation in consecutive interpreting - summary of a Ph.D. dissertation
Authors: Dam Helle V.
Published: February 2017

No abstract.
El Derecho de Habitar. Reflexión sobre los Desplazamientos Forzosos Y Los Movimientos Sociales / The Right to Inhabit. Reflection on Forced Displacement and Social Movements.
Authors: Sánchez Estévez Reyna
Published: February 2017

RESUMENEn este trabajo se exponen datos iniciales de una investigación sobre las protestas y luchas sociales en contra de los desplazamientos forzosos de pobladores de México, se da a conocer los lugares en los que se desarrollan las movilizaciones, los motivos que las originan y características de los sujetos participantes, también se realiza un primer análisis de los objetivos de lucha y se ofrecen algunos elementos de sus repertorios de protesta. Se realiza una reflexión sobre los daños que ocasionan estos desplazamientos en los seres humanos y sobre las nociones de riesgo y vulnerabilidad.Palabras Clave: Movimientos sociales, desalojos, vulnerabilidad.RESUMONeste trabalho são expostos os dados iniciais de uma pesquisa sobre os protestos e lutas sociais contra os deslocamentos forçados de populações do México, dão-se a conhecer os locais onde são desenvolvidas as manifestações, os motivos que as originam e as características dos sujeitos participantes, também se faz uma primeira análise dos objetivos da luta y são oferecidos alguns elementos do seu repertório de protesto. Se faz uma reflexão sobre os danos que estes deslocamentos ocasionam nos seres humanos e sobre as noções de risco vulnerabilidade. Palavras-Chave: autoestradas urbanas, justiça espacial, balanças.ABSTRACTThis paper exposes initial data from an investigation into the protests and social struggles against forced displacement of people from Mexico, it is given to know the places where protests are developed, the reasons which originate them and the characteristics of the participant subjects, a first analysis of the resistance objectives is also done and some elements of their repertoires of protest are offered. A reflection on the damage caused by these displacements in human beings and on the notions of risk and vulnerability is made.Keywords: Social movements, evictions, vulnerability
Desastres Ambientais e Conflitos Socioespaciais no Brasil / Environmental Disasters and Socio-Spatial Conflicts in Brazil
Authors: Da Mata Siqueira Antenora Maria , Nazareno Mendes Juliana , Lemos Filho Alex José
Published: February 2017

RESUMOOs desastres relacionados às águas, ocorridos no Brasil, aprofundaram e ampliaram as pesquisas sobre tais fenômenos. Este artigo analisa os conflitos decorrentes da resposta do governo da cidade de Campos dos Goytacazes/RJ às consequências dos desastres: o programa de habitação popular “Morar Feliz”. Realizaram-se levantamentos bibliográficos, coleta de dados em órgãos públicos e entrevistas com moradores reassentados. Os resultados indicam a existência de conflito de interesses que opõem os moradores que reivindicam ficar no bairro em que residem, ou próximo a ele, e o governo municipal, que promove a expansão urbana em áreas com insuficiência de infraestrutura urbana.Palavras-Chave: desastres ambientais, habitação popular, risco.RESUMENLos desastres relacionados con el agua que ocurrieron en Brasil profundizaron y ampliaron las investigaciones sobre estos fenómenos. En este artículo se analizan los conflictos que surgen como resultado de la respuesta del gobierno de la ciudad de Campos dos Goytacazes / RJ frente a las consecuencias de los desastres: el programa de vivienda pública "Morar Feliz". La investigación se basó en la literatura sobre el tema, en recolección de datos en los organismos públicos y en entrevistas con residentes reasentados. Los resultados indican la existencia de conflictos de intereses que oponen a los residentes que pretenden permanecer en el distrito en el que residen, o al menos cerca; al gobierno municipal, que promueve la expansión urbana en las zonas con insuficiencia de infraestructura urbana.Palabras Clave: Desastres ambientales, viviendas públicas, riesgo.ABSTRACTWater-related disasters occurred in Brazil deepened and expanded researches on such phenomena. This article analyzes the conflicts arising from the response of the government of the city of Campos dos Goytacazes / RJ concerning the consequences of these disasters: the public housing program "Morar Feliz". There were conducted bibliographic researches, data collection in public entities and interviews with residents resettled. The results indicate the existence of conflict of interests that opposes residents who claim to stay in the district in which they reside, or close to it; and the municipal government, which promotes urban sprawl in areas with lack of urban infrastructure.Keywords: Environmental disasters, public housing, risk.
O que pode uma geografia como corpo que dança? linguagem-experiencia 'gesto -movimento' (fragmentos) / What can a geography as dancing body? language-experience 'gesture-movement-affection' (fragments)
Authors: Queiroz Filho Antonio Carlos
Published: February 2017

RESUMOFeito de fragmentos, esse texto propõe pensar sobre relações e rebatimentos possíveis existentes entre linguagem e experiência na perspectiva de alguns autores pós-estruturalistas. Busquei na reflexão sobre o corpo e a dança um meio de problematizar essa questão e, ao mesmo tempo, lidar com uma Geografia como gesto que se estabelece nos afetos que fazem movimentar em nós, intensidades, potências e devires. “O que pode uma Geografia como corpo que dança?” é, para além de uma pergunta, um convite, uma proposição: por uma Geografia bailarina. Palavras-chave: Corpo – Dança – Geografia RESUMENHecha de fragmentos, este documento propone que pensar en las relaciones y las posibles repercusiones existentes entre el lenguaje y la experiencia desde la perspectiva de algunos autores postestructuralistas. Busqué en la reflexión sobre el cuerpo y bailar una manera de hablar de este tema y, al mismo tiempo, haciendo una geografía como algo que produce en nosotros los afectos. "¿Qué puede hacer una geografía como cuerpo de baile?" Está más allá de una pregunta, una invitación, una proposición: una geografía bailarina.Palabras clave: Cuerpo - Danza - Geografía ABSTRACTMade of fragments, this paper proposes to think about relations and possible repercussions existing between language and experience from the perspective of some post-structuralist authors. I sought in reflection about body and dance a way to discuss this issue and at the same time, making a geography as something that produces in us affections. “What can a Geography as dancing body?” is beyond a question, an invitation, a proposition: a ballerina geography. Keywords: Body – Dance – Geography
Las industrias convergentes y la ópera en los cines: de espectáculo tecnológico a evento mediático
Authors: Villanueva Benito Isabel , Lacasa-Mas Iván
Published: February 2017

Después de diez años, el cine y la ópera han consolidado un espectáculo en expansión global. Tras haber definido, en el año 2012, las características tecnológicas y comerciales que convertían estas retransmisiones en productos audiovisuales sostenibles, nuestro interés se centra ahora en conocer cuáles son las propiedades identitarias que, tras una década, han convertido a la ópera en los cines en un evento mediático nuevo y distinto en términos sociológicos. Superada una perspectiva principalmente tecnológica, el objetivo de esta investigación es, mediante una combinación de metodologías, (a) estudiar las particularidades de los eventos mediáticos operísticos, para (b) explicar algunos de los cambios en los comportamientos sociológicos de sus públicos. Este segundo estudio constata que estos espectáculos abren un “espacio entre convenciones” que brinda una gran oportunidad a ambas industrias culturales para dialogar con nuevas audiencias.
L’équipement emblématique, un levier de la régénération urbaine ?
Authors: Bouallag-Azoui Ouafida , Berezowska-Azzag Ewa
Published: February 2017

La réalisation d’équipements emblématiques (EE) pour affirmer l’identité métropolitaine de la capitale algérienne est l’une des priorités du Plan stratégique de développement d’Alger. Ces équipements sont imaginés comme des catalyseurs des mutations nécessaires à la régénération des localités pour s’adapter aux nouveaux besoins du développement métropolitain. Dans la réalité, cet urbanisme de projet n’apporte pas toujours les changements escomptés ; le centre des arts d’Alger Riad El Feth en est un exemple. Comment déterminer alors les facteurs de succès ou d’échec d’une telle édification dans le contexte local, en conjuguant les objectifs de métropolisation avec ceux de développement local ? Dans cet article, nous proposons la démarche de construction d’un outil qui permet de vérifier et d’évaluer l’effet de levier des EE sur les stratégies de régénération urbaine (RU) dans la perspective d’optimiser leurs effets positifs après leur réalisation ou, le cas échéant, de remédier aux insuffisances avant la prise de décision de localisation.
Spontaneous activation of visual pigments in relation to openness/closedness of chromophore-binding pocket
Authors: Yue Wendy Wing Sze , Frederiksen Rikard , Ren Xiaozhi , Luo Dong-Gen , Yamashita Takahiro , Shichida Yoshinori , Cornwall M Carter , Yau King-Wai
Published: February 2017

Visual pigments can be spontaneously activated by internal thermal energy, generating noise that interferes with real-light detection. Recently, we developed a physicochemical theory that successfully predicts the rate of spontaneous activity of representative rod and cone pigments from their peak-absorption wavelength (λmax), with pigments having longer λmax being noisier. Interestingly, cone pigments may generally be ~25 fold noisier than rod pigments of the same λmax, possibly ascribed to an ‘open’ chromophore-binding pocket in cone pigments defined by the capability of chromophore-exchange in darkness. Here, we show in mice that the λmax-dependence of pigment noise could be extended even to a mutant pigment, E122Q-rhodopsin. Moreover, although E122Q-rhodopsin shows some cone-pigment-like characteristics, its noise remained quantitatively predictable by the ‘non-open’ nature of its chromophore-binding pocket as in wild-type rhodopsin. The openness/closedness of the chromophore-binding pocket is potentially a useful indicator of whether a pigment is intended for detecting dim or bright light.
Combinatorial bZIP dimers display complex DNA-binding specificity landscapes
Authors: Rodríguez-Martínez José A , Reinke Aaron W , Bhimsaria Devesh , Keating Amy E , Ansari Aseem Z
Published: February 2017

How transcription factor dimerization impacts DNA-binding specificity is poorly understood. Guided by protein dimerization properties, we examined DNA binding specificities of 270 human bZIP pairs. DNA interactomes of 80 heterodimers and 22 homodimers revealed that 72% of heterodimer motifs correspond to conjoined half-sites preferred by partnering monomers. Remarkably, the remaining motifs are composed of variably-spaced half-sites (12%) or ‘emergent’ sites (16%) that cannot be readily inferred from half-site preferences of partnering monomers. These binding sites were biochemically validated by EMSA-FRET analysis and validated in vivo by ChIP-seq data from human cell lines. Focusing on ATF3, we observed distinct cognate site preferences conferred by different bZIP partners, and demonstrated that genome-wide binding of ATF3 is best explained by considering many dimers in which it participates. Importantly, our compendium of bZIP-DNA interactomes predicted bZIP binding to 156 disease associated SNPs, of which only 20 were previously annotated with known bZIP motifs.
Control of immune ligands by members of a cytomegalovirus gene expansion suppresses natural killer cell activation
Authors: Fielding Ceri A , Weekes Michael P , Nobre Luis V , Ruckova Eva , Wilkie Gavin S , Paulo Joao A , Chang Chiwen , Suárez Nicolás M , Davies James A , Antrobus Robin , Stanton Richard J , Aicheler Rebecca J , Nichols Hester , Vojtesek Borek , Trowsdale John , Davison Andrew J , Gygi Steven P , Tomasec Peter , Lehner Paul J , Wilkinson Gavin W G
Published: February 2017

The human cytomegalovirus (HCMV) US12 family consists of ten sequentially arranged genes (US12-21) with poorly characterized function. We now identify novel natural killer (NK) cell evasion functions for four members: US12, US14, US18 and US20. Using a systematic multiplexed proteomics approach to quantify ~1300 cell surface and ~7200 whole cell proteins, we demonstrate that the US12 family selectively targets plasma membrane proteins and plays key roles in regulating NK ligands, adhesion molecules and cytokine receptors. US18 and US20 work in concert to suppress cell surface expression of the critical NKp30 ligand B7-H6 thus inhibiting NK cell activation. The US12 family is therefore identified as a major new hub of immune regulation.
Folding behavior of a T-shaped, ribosome-binding translation enhancer implicated in a wide-spread conformational switch
Authors: Le My-Tra , Kasprzak Wojciech K , Kim Taejin , Gao Feng , Young Megan YL , Yuan Xuefeng , Shapiro Bruce A , Seog Joonil , Simon Anne E
Published: February 2017

Turnip crinkle virus contains a T-shaped, ribosome-binding, translation enhancer (TSS) in its 3’UTR that serves as a hub for interactions throughout the region. The viral RNA-dependent RNA polymerase (RdRp) causes the TSS/surrounding region to undergo a conformational shift postulated to inhibit translation. Using optical tweezers (OT) and steered molecular dynamic simulations (SMD), we found that the unusual stability of pseudoknotted element H4a/Ψ3 required five upstream adenylates, and H4a/Ψ3 was necessary for cooperative association of two other hairpins (H5/H4b) in Mg2+. SMD recapitulated the TSS unfolding order in the absence of Mg2+, showed dependence of the resistance to pulling on the 3D orientation and gave structural insights into the measured contour lengths of the TSS structure elements. Adenylate mutations eliminated one-site RdRp binding to the 3’UTR, suggesting that RdRp binding to the adenylates disrupts H4a/Ψ3, leading to loss of H5/H4b interaction and promoting a conformational switch interrupting translation and promoting replication.
Atomistic simulations indicate the c-subunit ring of the F1Fo ATP synthase is not the mitochondrial permeability transition pore
Authors: Zhou Wenchang , Marinelli Fabrizio , Nief Corrine , Faraldo-Gómez José D
Published: February 2017

Pathological metabolic conditions such as ischemia induce the rupture of the mitochondrial envelope and the release of pro-apoptotic proteins, leading to cell death. At the onset of this process, the inner mitochondrial membrane becomes depolarized and permeable to osmolytes, proposedly due to the opening of a non-selective protein channel of unknown molecular identity. A recent study purports that this channel, referred to as Mitochondrial Permeability Transition Pore (MPTP), is formed within the c-subunit ring of the ATP synthase, upon its dissociation from the catalytic domain of the enzyme. Here, we examine this claim for two c-rings of different lumen width, through calculations of their ion conductance and selectivity based on all-atom molecular dynamics simulations. We also quantify the likelihood that the lumen of these c-rings is in a hydrated, potentially conducting state rather than empty or blocked by lipid molecules. These calculations demonstrate that the structure and biophysical properties of a correctly assembled c-ring are inconsistent with those attributed to the MPTP.
Synchronous Double Cancer of the Common Bile Duct and the Ampulla of Vater Without Pancreaticobiliary Maljunction: A Case Report
Authors: Tanaka Ryota , Yamazoe Sadaaki , Amano Ryosuke , Kimura Kenjiro , Ohira Go , Hirata Keiichiro , Nishio Kohei , Miura Kotaro , Ohira Masaichi , Hirakawa Kosei
Published: February 2017

Synchronous double cancers in the biliary system are rare. Double cancer of the common bile duct (CBD) and the ampulla of Vater without pancreaticobiliary maljunction (PBM) is extremely rare. To our knowledge, only 7 cases have been reported previously. Here we report a case of synchronous double cancer of the CBD and the ampulla of Vater without PBM. A 63-year-old man was referred to our hospital with epigastric pain and jaundice. Computed tomography (CT) showed dilatation of both intrahepatic and intrapancreatic bile ducts, and slightly enhanced tumor in the middle part of the CBD and the ampulla of Vater. Endoscopic retrograde cholangiopancreatography (ERCP) showed a tuberous filling defect in the middle part of the CBD and an exposed tumor of the ampulla of Vater. Under a diagnosis of synchronous double cancer of the middle bile duct and the ampulla of Vater, pancreaticoduodenectomy was performed. Histopathologically, the ampulla of Vater tumor was well-differentiated tubular adenocarcinoma while the middle bile duct tumor was moderately-differentiated tubular adenocarcinoma. Normal mucosa was interposed between both tumors. These findings suggest that they were 2 primary tumors. Double cancer of the CBD and the ampulla of Vater without PBM is extremely rare. We report a case of synchronous double cancer of the CBD and the ampulla of Vater without PBM.
Amyloidogenicity and toxicity of the reverse and scrambled variants of amyloid‐β 1‐42
Authors: Vadukul Devkee M. , Gbajumo Oyinkansola , Marshall Karen E. , Serpell Louise C.
Published: February 2017

β‐amyloid 1‐42 (Aβ1‐42) is a self‐assembling peptide that goes through many conformational and morphological changes before forming the fibrils that are deposited in extracellular plaques characteristic of Alzheimer's disease. The link between Aβ1‐42 structure and toxicity is of major interest, in particular, the neurotoxic potential of oligomeric species. Many studies utilise reversed (Aβ42‐1) and scrambled (AβS) forms of amyloid‐β as control peptides. Here, using circular dichroism, thioflavin T fluorescence and transmission electron microscopy, we reveal that both control peptides self‐assemble to form fibres within 24 h. However, oligomeric Aβ reduces cell survival of hippocampal neurons, while Aβ42‐1 and Aβs have reduced effect on cellular health, which may arise from their ability to assemble rapidly to form protofibrils and fibrils.
Variations in pockmark composition at the Vestnesa Ridge: Insights from marine controlled source electromagnetic and seismic data
Authors: Goswami Bedanta K. , Weitemeyer Karen A. , Bünz Stefan , Minshull Timothy A. , Westbrook Graham K. , Ker Stephan , Sinha Martin C.
Published: February 2017

The Vestnesa Ridge marks the northern boundary of a known submarine gas hydrate province in the west Svalbard margin. Several seafloor pockmarks at the eastern segment of the ridge are sites of active methane venting. Until recently, seismic reflection data were the main tool for imaging beneath the ridge. Coincident controlled source electromagnetic (CSEM), high‐resolution two‐dimensional (2‐D) airgun, sweep frequency SYSIF, and three‐dimensional (3‐D) p‐cable seismic reflection data were acquired at the south‐eastern part of the ridge between 2011 and 2013. The CSEM and seismic data contain profiles across and along the ridge, passing several active and inactive pockmarks. Joint interpretation of resistivity models obtained from CSEM and seismic reflection data provides new information regarding the fluid composition beneath the pockmarks. There is considerable variation in transverse resistance and seismic reflection characteristics of the gas hydrate stability zone (GHSZ) between the ridge flanks and chimneys beneath pockmarks. Layered seismic reflectors on the flanks are associated with around 300 Ωm2 transverse resistance, whereas the seismic reflectors within the chimneys exhibit amplitude blanking and chaotic patterns. The transverse resistance of the GHSZ within the chimneys vary between 400 and 1200 Ωm2. Variance attributes obtained from the 3‐D p‐cable data also highlight faults and chimneys, which coincide with the resistivity anomalies. Based on the joint data interpretation, widespread gas hydrate presence is likely at the ridge, with both hydrates and free gas contained within the faults and chimneys. However, at the active chimneys the effect of gas likely dominates the resistive anomalies.
Ventilation history of Nordic Seas overflows during the last (de)glacial period revealed by species‐specific benthic foraminiferal 14C dates
Authors: Ezat Mohamed M. , Rasmussen Tine L. , Thornalley David J. R. , Olsen Jesper , Skinner Luke C. , Hönisch Bärbel , Groeneveld Jeroen
Published: February 2017

Formation of deep water in the high‐latitude North Atlantic is important for the global meridional ocean circulation, and its variability in the past may have played an important role in regional and global climate change. Here we study ocean circulation associated with the last (de)glacial period, using water‐column radiocarbon age reconstructions in the Faroe‐Shetland Channel, southeastern Norwegian Sea, and from the Iceland Basin, central North Atlantic. The presence of tephra layer Faroe Marine Ash Zone II, dated to ~26.7 ka, enables us to determine that the middepth (1179 m water depth) and shallow subsurface reservoir ages were ~1500 and 1100 14C years, respectively, older during the late glacial period compared to modern, suggesting substantial suppression of the overturning circulation in the Nordic Seas. During the late Last Glacial Maximum and the onset of deglaciation (~20–18 ka), Nordic Seas overflow was weak but active. During the early deglaciation (~17.5–14.5 ka), our data reveal large differences between 14C ventilation ages that are derived from dating different benthic foraminiferal species: Pyrgo and other miliolid species yield ventilation ages >6000 14C years, while all other species reveal ventilation ages <2000 14C years. These data either suggest subcentennial, regional, circulation changes or that miliolid‐based 14C ages are biased due to taphonomic or vital processes. Implications of each interpretation are discussed. Regardless of this “enigma,” the onset of the Bølling‐Allerød interstadial (14.5 ka) is clearly marked by an increase in middepth Nordic Seas ventilation and the renewal of a stronger overflow.
Mature adipocytes observed to undergo reproliferation and polyploidy
Authors: Xu Pengfei , Li Jiao , Liu Jin , Wang Jing , Wu Zekai , Zhang Xiaotian , Zhai Yonggong
Published: February 2017

Lipid‐filled mature adipocytes are important for the study of lipid metabolism and in the development of obesity, but whether they are capable of reproliferation is still controversial. Here, we monitored lipid droplet dynamics and adipocyte reproliferation in live, differentiated 3T3‐L1 cells using a phase‐contrast microscope in real time. Phase‐contrast microscopy achieves a similar visual effect in situ to that obtained using traditional dyes such as Oil Red O and BODIPY in vitro. Using this method, we captured the process that lipid droplets use for dynamic fusion in living cells. Unexpectedly, we acquired images of the moment that differentiated 3T3‐L1 cells containing lipid droplets entered mitosis. In addition, we observed some binucleated mature adipocytes. This information provides a better understanding of the adipocyte differentiation process.
A new two‐microphone Gauss‐Seidel pseudo affine projection algorithm for speech quality enhancement
Authors: Djendi Mohamed
Published: February 2017

This study addresses the problem of speech quality enhancement by adaptive and nonadaptive filtering algorithms. The well‐known two‐microphone forward blind source separation (TM‐FBSS) structure has been largely studied in the literature. Several two‐microphone algorithms combined with TM‐FBSS have been recently proposed. In this study, we propose 2 contributions: In the first, a new two‐microphone Gauss‐Seidel pseudo affine projection (TM‐GSPAP) algorithm is combined with TM‐FBSS. In the second, we propose to use the new TM‐GSPAP algorithm in speech enhancement. Furthermore, we show the efficiency of the proposed TM‐GSPAP algorithm in speech enhancement when highly noisy observations are available. To validate the good performances of our algorithm, we have evaluated the adaptive filtering properties in computational complexity and convergence speed performance by system mismatch criteria. A fair comparison with adaptive and nonadaptive noise reduction algorithms are also presented. The adaptive algorithms are the well‐known two‐microphone normalized least mean square algorithm, and the recently published two‐microphone pseudo affine projection algorithm. The nonadaptive algorithms are the one‐microphone spectral subtraction and the two‐microphone Wiener filter algorithm. We evalute the quality of the output speech signal in each algorithm by several objective and subjective criteria as the segmental signal‐to‐noise ratio, cepstral distance, perceptual evaluation of speech quality, and the mean opinion score. Finally, we validate the superior performances of the proposed algorithm with physically measured signals.
Scaling the Aspect Ratio of Nanoscale Closely Packed Silicon Vias by MacEtch: Kinetics of Carrier Generation and Mass Transport
Authors: Kim Jeong Dong , Mohseni Parsian K. , Balasundaram Karthik , Ranganathan Srikanth , Pachamuthu Jayavel , Coleman James J. , Li Xiuling
Published: February 2017

Metal‐assisted chemical etching (MacEtch) has shown tremendous success as an anisotropic wet etching method to produce ultrahigh aspect ratio semiconductor nanowire arrays, where a metal mesh pattern serves as the catalyst. However, producing vertical via arrays using MacEtch, which requires a pattern of discrete metal disks as the catalyst, has often been challenging because of the detouring of individual catalyst disks off the vertical path while descending, especially at submicron scales. Here, the realization of ordered, vertical, and high aspect ratio silicon via arrays by MacEtch is reported, with diameters scaled from 900 all the way down to sub‐100 nm. Systematic variation of the diameter and pitch of the metal catalyst pattern and the etching solution composition allows the extraction of a physical model that, for the first time, clearly reveals the roles of the two fundamental kinetic mechanisms in MacEtch, carrier generation and mass transport. Ordered submicron diameter silicon via arrays with record aspect ratio are produced, which can directly impact the through‐silicon‐via technology, high density storage, photonic crystal membrane, and other related applications.
Nitrogen‐Doped Co3O4 Mesoporous Nanowire Arrays as an Additive‐Free Air‐Cathode for Flexible Solid‐State Zinc–Air Batteries
Authors: Yu Minghao , Wang Zhengke , Hou Cheng , Wang Zilong , Liang Chaolun , Zhao Cunyuan , Tong Yexiang , Lu Xihong , Yang Shihe
Published: February 2017

The kinetically sluggish rate of oxygen reduction reaction (ORR) on the cathode side is one of the main bottlenecks of zinc‐air batteries (ZABs), and thus the search for an efficient and cost‐effective catalyst for ORR is highly pursued. Co3O4 has received ever‐growing interest as a promising ORR catalyst due to the unique advantages of low‐cost, earth abundance and decent catalytic activity. However, owing to the poor conductivity as a result of its semiconducting nature, the ORR activity of the Co3O4 catalyst is still far below the expectation. Herein, we report a controllable N‐doping strategy to significantly improve the catalytic activity of Co3O4 for ORR and demonstrate these N doped Co3O4 nanowires as an additive‐free air‐cathode for flexible solid‐state zinc‐air batteries. The results of experiments and DFT calculations reveal that the catalytic activity is promoted by the N dopant through a combined set of factors, including enhanced electronic conductivity, increased O2 adsorption strength and improved reaction kinetics. Finally, the assembly of all‐solid‐state ZABs based on the optimized cathode exhibit a high volumetric capacity of 98.1 mAh cm‐3 and outstanding flexibility. The demonstration of such flexible ZABs provides valuable insights that point the way to the redesign of emerging portable electronics.
Electronic Properties of Copper(I) Thiocyanate (CuSCN)
Authors: Pattanasattayavong Pichaya , Promarak Vinich , Anthopoulos Thomas D.
Published: February 2017

With the emerging applications of copper(I) thiocyanate (CuSCN) as a transparent and solution‐processable hole‐transporting semiconductor in numerous opto/electronic devices, fundamental studies that cast light on the charge transport physics are essential as they provide insights critical for further materials and devices performance advancement. The aim of this article is to provide a comprehensive and up‐to‐date report of the electronic properties of CuSCN with key emphasis on the structure–property relationship. The article is divided into four parts. In the first section, recent works on density functional theory calculations of the electronic band structure of hexagonal β‐CuSCN are reviewed. Following this, various defects that may contribute to the conductivity of CuSCN are discussed, and newly predicted phases characterized by layered 2‐dimensional‐like structures are highlighted. Finally, a summary of recent studies on the band‐tail states and hole transport mechanisms in solution‐deposited, polycrystalline CuSCN layers is presented.