bluuebunny/crossref_metadata_2025 huggingface dataset:
Al otro lado del espejo de Joan Fontcuberta
Authors: Farell Lozano Pau
Published: October 2014

Joan Fontcuberta, fotógrafo y artista internacional, juega a menudo con las prácticas documentales, llevando al límite la veracidad de la narración y articulando la representación para ponerla en evidencia. Entre 2012 y 2013, realizó una muestra itinerante que consta de una colección de imágenes fotográficas particulares, encontradas en Internet. Este articulo gira entorno a una de sus últimas obras, combinando una conversación con el artista y una reflexión que puede ayudar a situar la autoría, la veracidad fotográfica y la identidad entorno la conjetura actual y ante el circuito de imágenes sin fin.http://dx.doi.org/10.7203/eari.5.3519
Iniciativas didácticas para el acercamiento en los centros educativos de propuestas sobre arte objetual.
Authors: Hervás Asins Lucía
Published: October 2014

El arte objetual nos ofrece distintas posibilidades en educación artística. Actualmente en nuestro país, existen diversas vías de expansión en este sentido, impulsadas por algunos profesores, centros educativos, asociaciones de colegios, museos y fundaciones, hecho que se ilustrará con algunos ejemplos relevantes para nuestro estudio. Por ello la intención que nos ocupa, es la de hacer una aportación innovadora que amplíe la investigación de resultados y procesos educativos artísticos distintos de los tradicionales que aun se siguen manteniendo en nuestro Sistema Educativo. Estamos rodeados de objetos en nuestra sociedad de consumo. Se podría decir, metafóricamente hablando, que los objetos se pueden convertir en extensiones de las funciones del ser humano. A partir de propuestas abiertas de trabajo y tomando como referencia la obra de los artistas como Carmen Calvo, Chema Madoz y Joan Brossa, se ha realizado en diferentes Institutos de Educación Secundaria de la Comunidad Valenciana, un proyecto del cual se analizarán algunos casos, que nos permitirán determinar el grado de competencias que es posible adquirir en Educación Artística por los alumnos, utilizando el objeto cotidiano como recurso, mostrando la idoneidad del arte objetual para la adquisición de las competencias establecidas en el currículum. El resultado de esta propuesta es la aportación de nuevos conceptos artísticos al estudiante, y a su entorno bien a su familia y al centro educativo en el que estudia.http://dx.doi.org/10.7203/eari.5.3553
Créditos
Authors: Domínguez Ruiz Ricardo
Published: October 2014

Créditos EARI 5
Adiponectin is essential for lipid homeostasis and survival under insulin deficiency and promotes β-cell regeneration
Authors: Ye Risheng , Holland William L , Gordillo Ruth , Wang Miao , Wang Qiong A , Shao Mengle , Morley Thomas S , Gupta Rana K , Stahl Andreas , Scherer Philipp E
Published: October 2014

As an adipokine in circulation, adiponectin has been extensively studied for its beneficial metabolic effects. While many important functions have been attributed to adiponectin under high-fat diet conditions, little is known about its essential role under regular chow. Employing a mouse model with inducible, acute β-cell ablation, we uncovered an essential role of adiponectin under insulinopenic conditions to maintain minimal lipid homeostasis. When insulin levels are marginal, adiponectin is critical for insulin signaling, endocytosis, and lipid uptake in subcutaneous white adipose tissue. In the absence of both insulin and adiponectin, severe lipoatrophy and hyperlipidemia lead to lethality. In contrast, elevated adiponectin levels improve systemic lipid metabolism in the near absence of insulin. Moreover, adiponectin is sufficient to mitigate local lipotoxicity in pancreatic islets, and it promotes reconstitution of β-cell mass, eventually reinstating glycemic control. We uncovered an essential new role for adiponectin, with major implications for type 1 diabetes.
Improving pandemic influenza risk assessment
Authors: Russell Colin A , Kasson Peter M , Donis Ruben O , Riley Steven , Dunbar John , Rambaut Andrew , Asher Jason , Burke Stephen , Davis C Todd , Garten Rebecca J , Gnanakaran Sandrasegaram , Hay Simon I , Herfst Sander , Lewis Nicola S , Lloyd-Smith James O , Macken Catherine A , Maurer-Stroh Sebastian , Neuhaus Elizabeth , Parrish Colin R , Pepin Kim M , Shepard Samuel S , Smith David L , Suarez David L , Trock Susan C , Widdowson Marc-Alain , George Dylan B , Lipsitch Marc , Bloom Jesse D
Published: October 2014

Assessing the pandemic risk posed by specific non-human influenza A viruses is an important goal in public health research. As influenza virus genome sequencing becomes cheaper, faster, and more readily available, the ability to predict pandemic potential from sequence data could transform pandemic influenza risk assessment capabilities. However, the complexities of the relationships between virus genotype and phenotype make such predictions extremely difficult. The integration of experimental work, computational tool development, and analysis of evolutionary pathways, together with refinements to influenza surveillance, has the potential to transform our ability to assess the risks posed to humans by non-human influenza viruses and lead to improved pandemic preparedness and response.
Phase transitions of multivalent proteins can promote clustering of membrane receptors
Authors: Banjade Sudeep , Rosen Michael K
Published: October 2014

Clustering of proteins into micrometer-sized structures at membranes is observed in many signaling pathways. Most models of clustering are specific to particular systems, and relationships between physical properties of the clusters and their molecular components are not well understood. We report biochemical reconstitution on supported lipid bilayers of protein clusters containing the adhesion receptor Nephrin and its cytoplasmic partners, Nck and N-WASP. With Nephrin attached to the bilayer, multivalent interactions enable these proteins to polymerize on the membrane surface and undergo two-dimensional phase separation, producing micrometer-sized clusters. Dynamics and thermodynamics of the clusters are modulated by the valencies and affinities of the interacting species. In the presence of the Arp2/3 complex, the clusters assemble actin filaments, suggesting that clustering of regulatory factors could promote local actin assembly at membranes. Interactions between multivalent proteins could be a general mechanism for cytoplasmic adaptor proteins to organize membrane receptors into micrometer-scale signaling zones.
Development of the Online Repository of Theses and Dissertations of the University of Cebu – Graduate School Library (ucGSLIB)
Authors: DINAUANAO AAHRON M.
Published: October 2014

Library provides both printed and unprinted materials that contain informationbasic in today’sknowledge-basedsociety.The roleof the libraryis not lim-ited to the promotion of readership but also includes the promotion of interests of readers who are ready to embrace technological advancements brought aboutby the emerging technologies of the 21st century. These digital technologies havechanged the way the library materials are accessed, maintained, and preserved ina repository.  At the University of Cebu (UC), materials such as theses and dissertationsdone bythe graduate students arenot availableonline. Mostof the librarypatronshavedifficulty in locating these resources.The goal of this study was todevelopan online repositoryof theses and dissertationsof the UCGS . A combinationof descriptiveand quasi-experimental designs was used. Dataobtainedthroughquestionnaires,interviews,and content analysis wereused in systemconstruction.The researcherdesigned and developedthe online repositorythatadheresto the standardsfor database management, searchquery,user applicationinterface,and data integrity as tested byIT expertsand end-users. The researcherrecommendsthe deployment,promotionand maintenance of the ucGSlib.Keywords: ICT, electronic thesis and dissertation (ETD), institutional repository (IR),library, Graduate School, ucGSlib, descriptive design, Cebu City, Philippines
Communication Styles, Multiple Intelligences, and Job Satisfaction of the SPED-Integrated School for Exceptional Children Graduates
Authors: JUDITH VANESSA JOY Z.
Published: October 2014

The search for effective approaches to educating and preparing “gifted”students for the world of work continues. These approaches guide administratorsin developing appropriate responses. The study aimed at identifying thecommunication styles, multiple intelligences, and job satisfaction of the graduatesof SPED-Integrated School for Exceptional Children in Iloilo City, Philippineswhen taken as a whole and grouped according to certain variables. It utilized thedescriptive research design. Pilot-tested questionnaires were used to gather datafrom 85 participants representing 53% of the graduates of SPED-ISEC from1978-1988. The participants were selected using incidental sampling technique.The statistical measures used were mean, standard deviation, percentage, t-test, Pearson’s r, and ANOVA.  The study reveals that the graduates were aggressive communicators, with varied intelligences, and were satisfied with their jobs.Hence, the administration of SPED-ISEC should conduct regular evaluation ofthe curricula to respond to the dynamic giftedness of each student. Likewise,teachers should be given opportunities for professional growth and be updated of the recent innovations in educating “gifted students.”Keywords: Education, graduates, multiple intelligences, communication styles, jobsatisfaction, SPED-Integrated school, descriptive design, Philippines
Ethnoscience among Select Indigenous Groups in Mindanao
Authors: VALDEZ ANABELIE V.
Published: October 2014

New technologies and scientific discoveries are upon modern man, rendering obsolete at a very rapid pace existing technology. In the maelstrom of all these prodigious changes, some groups of people have not felt the impact of modern science on their lives. It is in this line where the ethnoscience of some select indigenous groups in Mindanao were explored, specifically the ethnoscinece among Subanen in Lapuyan Zamboanga del Sur and the Mansaka in Mabini Compostela Valley. Purposive and snowball sampling were used in selecting the participants. Ethnographic techniques were used in this naturalistic and qualitative study. The researcher immersed in each community using questionnaire, interview guide, individual and focus group discussions, observation checklist, field notebook, and other instruments. Results revealed that the Subanen and Mansaka farmers were mostly 61 years old and have low level of educational attainment. Magical, traditional, and factual procedures and techniques figured prominently among the crop farming practices, food gathering and food preparation among Subanen and Mansaka. Their balyan healer used a combination of magical, traditional, and factual techniques in treating diseases. Therefore, these groups of people retained and preserved their unique identity and natural knowledge despite tremendous impact of modern technologies and discoveries in multifarious disciplines.Keywords: Ethnoscience, ethnofarming, ethnomedicine, qualitative research usingethnographic techniques, Philippines
The Mansaka Culture of Maragusan in Southern Philippines: From the Elders’ Lens
Authors: ANGON-OPENA HILDA V. , GEMPES GLORIA P.
Published: October 2014

This ethnographic study portrays and documents the culture of the Mansaka tribe in Maragusan,a municipality of Davao Del Norte, Philippines. The term Mansaka stems from the place of origin, as a group of people living in the center of the forest. They are the first settlers of Maragusan. This qualitative study aims to document a narrative description of Mansaka culture as a ready reference for the people of Maragusan. This undertaking involved two focus group discussions (FGD) with seven participants each group and 14 key informants or a total of 28 Mansaka elders. We employed purposive sampling in determining the samples of the study. In Mansaka culture, the elders are the fundamental link in the continuity of the past to the future to complete the circle of life. Aside from focus group discussion and in-depth interview, we employed other data gathering techniques like participant observation and field notes. The findings revealed that the majority of the Mansakas have no college education, mostly farmers, and willing to die for the ownership of their land. The majority was converted to Christianity, but still holding on to their customs and traditions. These customs and traditions are authentically described in this study.Keywords: Ethnography, Mansaka, culture, elders, qualitative, Philippines
Determinants of Purchase Decisions and Consumers’ Willingness to Pay for Green Products
Authors: SALVADOR LISA S.
Published: October 2014

The purpose of the study was to investigate the influence of consumers buyingdecisions and willingness to pay for green products. Five variables were examinedfor the determinants, and three questions were considered for the willingness to payfor green products. Data were collected through questionnaires. Utilizing stratifiedsampling technique, the researcher considered 310 respondents. The study revealeda low to moderate influence of personal , social , economic, psychological factorsand product attributes on consumers purchase decision This means specific itemsare influential to one demographic but not to another. Eighty four percent of thetotal participants in the study are willing to pay for green products, and from thosewho are willing to pay, 39% perceived they have the willingness and ability topay up to 5% more of the product price. Statistical analysis revealed a significantdifference between income groups and willingness to pay while psychological and economic determinant were found to be significantly related to willingness to payfor green products. This means affordability, income adequacy, motivations andenvironmental concerns are positively linked to willingness to pay. This studyadded to the literature of green consumer behavior and provided a consumers’ viewpoint to aid in the development of marketing strategies.Keywords: Economics, personal factors, social influence, economic factors, productattributes, psychological influence, descriptive-correlational design, Philippines
Influence of the sediment supply texture on morphological adjustments in gravel‐bed rivers
Authors: Ferrer‐Boix Carles , Hassan Marwan A.
Published: October 2014

The role played by the texture of the sediment supply on channel bed adjustments in gravel‐bed rivers is poorly understood. To address this issue, an experimental campaign has been designed. Flume experiments lasting 96 h in a 9 m long, 0.60 m wide have been performed with different sand‐gravel mixtures as feed textures. The response of the surface texture has been found to be highly dependent on the grain size distribution of the feed. When the feed texture included gravel, the finest fractions of the sediment supply infiltrate beneath the surface. Conversely, sand remains on the surface when the feed texture lacks gravel. This different textural response becomes obscured when water discharge increases. Further, the sediment transport rate approaches the feed rate differently depending on the content of gravel in the feed texture. When a small proportion of gravel is part of the feed texture, bed load transport rate asymptotically approaches the feed rate. However, when a significant fraction of gravel is part of the feed grain size distribution, bed load transport rate approaches the feed rate by following an oscillatory path. These findings have been verified in terms of a one‐dimensional numerical model. This modeling reveals that the higher the differences in mobility among the grain sizes contained in the feed texture, the more evident is the nonasymptotic transient trend toward equilibrium.
Seismic evidence of continental margin influence on the NinetyEast Ridge in the Bay of Bengal
Authors: Moeremans Raphaele E. , Singh Satish C.
Published: October 2014

The NinetyEast Ridge (NER), one of the most enigmatic features in the Indian Ocean, is covered by thick Bengal Fan sediment north of 9°N. We present seismic reflection data on the eastern flank of the NER, at 10°N, that show the presence of 4–5 km thick sediments beneath the Bengal Fan sediments. These sediments can be imaged up to 60 km beneath the Andaman fore‐arc accretionary wedge, suggesting that the décollement lies above these sediments. The presence of thick sediments above the northernmost segment of the NER suggests that this segment was close to a continental margin during its emplacement. We propose that these sediments were deposited soon after the breakup of India and Antarctica, between 130 and 100 Ma, and might act as source rocks for oil and gas generation beneath recent Bengal Fan sediments. Furthermore, subducting thick sediments can significantly change the seismogenic behavior of the Andaman subduction zone.
Upscaling carbon dioxide emissions from lakes
Authors: Seekell David A. , Carr Joel A. , Gudasz Cristian , Karlsson Jan
Published: October 2014

Quantifying CO2 fluxes from lakes to the atmosphere is important for balancing regional and global‐scale carbon budgets. CO2 emissions are estimated through statistical upscaling procedures that aggregate data from a large number of lakes. However, aggregation can bias flux estimates if the physical and chemical factors determining CO2 exchange between water and the atmosphere are not independent. We evaluated the magnitude of aggregation biases with moment expansions and pCO2 data from 5140 Swedish lakes. The direction of the aggregation bias depends on lake size; mean flux was overestimated by 4% for small lakes (0.01–0.1 km2) but underestimated by 13% for large lakes (100–1000 km2). Simple covariance‐based correction factors were generated to adjust for upscaling biases. These correction factors represent an easily interpretable and implemented approach to improving the accuracy of regional and global estimates of lake CO2 emissions.
Perchlorate‐induced combustion of organic matter with variable molecular weights: Implications for Mars missions
Authors: Sephton Mark A. , Lewis James M. T. , Watson Jonathan S. , Montgomery Wren , Garnier Carole
Published: October 2014

Instruments on the Viking landers and Curiosity rover analyzed samples of Mars and detected carbon dioxide and organic compounds of uncertain origin. Mineral‐assisted reactions are leading to uncertainty, particularly those involving perchlorate minerals which thermally decompose to produce chlorine and oxygen which can then react with organic matter to generate organochlorine compounds and carbon dioxide. Although generally considered a problem for interpretation, the release profiles of generated gases can indicate the type of organic matter present. We have performed a set of experiments with perchlorate and organic matter of variable molecular weights. Results indicate that organic susceptibility to thermal degradation and mineral‐assisted reactions is related to molecular weight. Low molecular weight organic matter reacts at lower temperatures than its high molecular weight counterparts. The natural occurrence and association of organic matter with differing molecular weights helps to discriminate between contamination (usually low molecular weight organic matter only) and indigenous carbon (commonly low and high molecular weight organic matter together). Our results can be used to provide insights into data returning from Mars.
Asymmetry of the Bjerknes positive feedback between the two types of El Niño
Authors: Zheng Fei , Fang Xiang‐Hui , Yu Jin‐Yi , Zhu Jiang
Published: October 2014

Corresponding to the pronounced amplitude asymmetry for the central Pacific (CP) and eastern Pacific (EP) types of El Niño, an asymmetry in the strength of the Bjerknes positive feedback is found between these two types of El Niño, which is manifested as a weaker relationship between the zonal wind anomaly and the zonal gradient of sea surface temperature (SST) anomaly in the CP El Niño. The strength asymmetry mainly comes from a weaker sensitivity of the zonal gradient of sea level pressure (SLP) anomaly to that of diabatic heating anomaly during CP El Niño. This weaker sensitivity is caused by (1) a large cancelation induced by the negative SST‐cloud thermodynamic feedback to the positive dynamical feedback for CP El Niño, (2) an off‐equator shift of the maximum SLP anomalies during CP El Niño, and (3) a suppression of the mean low‐level convergence when CP El Niño events occur more often.
Proton acceleration at two‐dimensional dipolarization fronts in the magnetotail
Authors: Greco A. , Artemyev A. , Zimbardo G.
Published: October 2014

Transient reconnection events in the planetary magnetotail give rise to fast plasma jets, whose leading edges are called dipolarization fronts. We perform a test particle simulation of ion acceleration in a 2‐D model of dipolarization fronts. We study the dependence of acceleration on several parameters of the model. We obtain that the interaction between the dipolarization front and particles depends on their initial energy h0, resulting in a moderate increase of the gained energy with h0. The front amplitude Bmax has been varied from 10 nT to 40 nT in order to study its influence on the particle gyro‐radii and, in turn, on interaction with the front. As expected, the energy gained by particles increases with Bmax. We find that the acceleration strongly depends on the front velocity vφ, which we chose to vary from 200 km/s to 750 km/s. The simulations pointed out that higher energies have been reached with fast fronts, ranging from 50 to 100 keV. We also study how the average maximum energy attained by ions, 〈hmax〉, depends on the y extent of the front: at variance with expectations, the energy gain decreases with the increase of the y size of the front for small values of that size; increasing further, the scaling of 〈hmax〉 with the y size seems to indicate a slow growth. We also study the energy and velocity distributions functions of ions accelerated by dipolarization fronts and compare these distributions with spacecraft observations.
Coupling between atmospheric layers in gaseous giant planets due to lightning‐generated electromagnetic pulses
Authors: Luque A. , Dubrovin D. , Gordillo‐Vázquez F. J. , Ebert U. , Parra‐Rojas F. C. , Yair Y. , Price C.
Published: October 2014

Atmospheric electricity has been detected in all gaseous giants of our solar system and is therefore likely present also in extrasolar planets. Building upon measurements from Saturn and Jupiter, we investigate how the electromagnetic pulse emitted by a lightning stroke affects upper layers of a gaseous giant. This effect is probably significantly stronger than that on Earth. We find that electrically active storms may create a localized but long‐lasting layer of enhanced ionization of up to 103 cm−3 free electrons below the ionosphere, thus extending the ionosphere downward. We also estimate that the electromagnetic pulse transports 107 J to 1010 J toward the ionosphere. There emissions of light of up to 108 J would create a transient luminous event analogous to a terrestrial “elve.”
Mechanics of two interacting magma‐driven fractures: A numerical study
Authors: Zhang Xi , Bunger Andrew P. , Jeffrey Robert G.
Published: October 2014

To understand magma focusing from broad melting zones in the crust, propagation in brittle rocks of two interacting dikes ascending from a single deep source has been modeled using a time‐dependent plane strain hydraulic fracturing model. The source is assumed to generate a constant influx rate to feed the dike growth, which is also aided by buoyancy effects. In contrast to uncoupled model results, the simultaneous parallel growth of two dikes to a certain distance is found to occur provided that the two dikes are initially of different heights, which might be produced either by previous magma intrusion or during nucleation. The shorter dike will chase the longer one and they can either progressively merge or continue subparallel growth at a reduced spacing, depending on the deviator stress between the vertical and horizontal stresses and the initial lateral separation, with parameters given in dimensionless forms. Numerical results reveal the mechanics for simultaneous ascents of two subparallel dikes, in that dike interaction can produce a low‐stress field, which is just above the tip of the shorter dike, favorable to growth of the shorter dike. The energy analysis indicates that the energy required for two subparallel dikes is less than that for a single dike during the late‐time buoyancy‐viscosity propagation stage where considerable ascent occurs. This growth behavior might provide the mechanism for simultaneous, instead of sequential, growth of various dikes in a single set.
Nocturnal loss of NOx during the 2010 CalNex‐LA study in the Los Angeles Basin
Authors: Tsai Catalina , Wong Clare , Hurlock Steve , Pikelnaya Olga , Mielke Levi H. , Osthoff Hans D. , Flynn James H. , Haman Christine , Lefer Barry , Gilman Jessica , de Gouw Joost , Stutz Jochen
Published: October 2014

The chemical removal of NOx at night in urban areas remains poorly constrained due to uncertainties in the contribution of various loss pathways and the impact of the suppressed nocturnal vertical mixing. Here we present long‐path differential optical absorption spectroscopy observations of nocturnal vertical concentration profiles of O3, NO2, and NO3 in the lower atmosphere (33–556 m above ground level) measured during the CalNex‐LA 2010 study. Positive nocturnal vertical gradients of O3 and NO3 and negative gradients of NO2 were observed during the night. Relatively short lifetime of nocturnal NO3 (less than 1000 s) and high nighttime steady state N2O5 mixing ratios (up to 2 ppb) indicated active nocturnal chemistry during CalNex. Comparison of modeled and observed altitude‐resolved NO3 loss frequencies shows that hydrolysis of N2O5 on aerosols was the dominant loss pathway of NO3 and NOx. Based on this argument, the nocturnal loss rates of NOx, L(NOx), at different altitudes and averaged over the lowest 550 m of the atmosphere were calculated. The nocturnally averaged L(NOx) ranged between 0.8 and 1.3 ppb h−1 for the lower atmosphere with the L(NOx) for the first 8 days at about 1 ppb h−1. This number is close to the one previously determined in Houston in 2009 of ~0.9 ppb h−1. Comparisons between daytime NOx loss due to the OH + NO2 reaction and nighttime L(NOx) show that during CalNex, nocturnal chemistry contributed an average of 60% to the removal of NOx in a 24 h period in the lower atmosphere.
Observations of rock spectral classes by the Opportunity rover's Pancam on northern Cape York and on Matijevic Hill, Endeavour Crater, Mars
Authors: Farrand W. H. , Bell J. F. , Johnson J. R. , Rice M. S. , Jolliff B. L. , Arvidson R. E.
Published: October 2014

The Opportunity rover's exploration of the portion of the rim of Endeavour crater known as Cape York included examination of the sulfate‐bearing Grasberg formation and the Matijevic Hill region. Multispectral visible and near‐infrared (VNIR) Pancam observations were used to characterize reflectance properties of rock units. Using spectral end‐member detection and classification approaches including a principal components/n‐dimensional visualization, automatic sequential maximum angle convex cone method, and classification through hierarchical clustering, six main spectral classes of rock surfaces were identified: light‐toned veins, Grasberg fm., the smectite‐bearing Matijevic formation, the hematitic “blueberry” spherules, resistant spherules within the Matijevic fm. dubbed “newberries,” and the Shoemaker formation impact breccia. Some of these could be divided into spectral subclasses. There were three types of veins: veins in the bench unit of Cape York, thinner veins in the Matijevic fm., and boxwork pattern‐forming veins. The bench unit veins had higher 535 nm band depths than the other two vein subclasses and a steeper 934 to 1009 nm slope. The Grasberg fm. has VNIR spectral features that are interpreted to indicate higher fractions of red hematite than in the sulfate‐bearing Burns Fm. The Matijevic fm. includes both light‐toned, fine‐grained matrix, and dark‐toned veneers. The latter has a weak near‐infrared absorption band centered near 950 nm consistent with nontronite. Observations of Rock Abrasion Tool brushed and ground newberries indicated that cuttings from the RAT grind had a longer wavelength reflectance maximum and deeper 535 nm band depth, consistent with more oxidized materials. Greater oxidation of cementing materials in the newberries is consistent with a diagenetic concretion origin.
Simultaneous measurement of unfrozen water content and ice content in frozen soil using gamma ray attenuation and TDR
Authors: Zhou Xiaohai , Zhou Jian , Kinzelbach Wolfgang , Stauffer Fritz
Published: October 2014

The freezing temperature of water in soil is not constant but varies over a range determined by soil texture. Consequently, the amounts of unfrozen water and ice change with temperature in frozen soil, which in turn affects hydraulic, thermal, and mechanical properties of frozen soil. In this paper, an Am‐241 gamma ray source and time‐domain reflectometry (TDR) were combined to measure unfrozen water content and ice content in frozen soil simultaneously. The gamma ray attenuation was used to determine total water content. The TDR was used to determine the dielectric constant of the frozen soil. Based on a four‐phase mixing model, the amount of unfrozen water content in the frozen soil could be determined. The ice content was inferred by the difference between total water content and unfrozen water content. The gamma ray attenuation and the TDR were both calibrated by a gravimetric method. Water contents measured by gamma ray attenuation and TDR in an unfrozen silt column under infiltration were compared and showed that the two methods have the same accuracy and response to changes of water content. Unidirectional column freezing experiments were performed to apply the combined method of gamma ray attenuation and TDR for measuring unfrozen water content and ice content. The measurement error of the gamma ray attenuation and TDR was around 0.02 and 0.01 m3/m3, respectively. The overestimation of unfrozen water in frozen soil by TDR alone was quantified and found to depend on the amount of ice content. The higher the ice content, the larger the overestimation. The study confirmed that the combined method could accurately determine unfrozen water content and ice content in frozen soil. The results of soil column freezing experiments indicate that total water content distribution is affected by available pore space and the freezing front advance rate. It was found that there is similarity between the soil water characteristic and the soil freezing characteristic of variably saturated soil. Unfrozen water content is independent of total water content and affected only by temperature when the freezing point is reached.
Bifunctional Squaramide Catalysts with the Same Absolute Chirality for the Diastereodivergent Access to Densely Functionalised Cyclohexanes through Enantioselective Domino Reactions. Synthesis and Mechanistic Studies
Authors: Martínez Jose I. , Villar Laura , Uria Uxue , Carrillo Luisa , Reyes Efraím , Vicario Jose L.
Published: October 2014

We have developed a procedure for the stereoselective and diastereodivergent synthesis of densely functionalised cyclohexanes containing four stereocentres through an asymmetric Michael‐initiated ring closure (MIRC) cascade reaction employing hydrogen‐bond catalysis, which is able to prepare adducts with different absolute configurations starting from the same starting materials. The overall process involves a highly diastereo‐ and enantioselective Michael/Henry cascade reaction between a wide range of nitroalkenes and α‐nitro‐δ‐oxo esters, allowing access to different diastereoisomers of the final adduct by introducing subtle changes in the general (R,R)‐configured bifunctional tertiary amine/squaramide catalyst structure. Moreover, this methodology is also amenable to a three‐component one‐pot procedure, leading to the formation of the same adducts with very good results directly from commercially available reagents, on a multigram scale, and employing a very low catalyst loading. Furthermore, a detailed experimental and computational study is described which shows the origin of the diastereodivergent behaviour of these structurally similar catalysts and the nature of the substrate–catalyst interaction.

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Membrane reactor immobilized with palladium‐loaded polymer nanogel for continuous‐flow Suzuki coupling reaction
Authors: Seto Hirokazu , Yoneda Tamami , Morii Takato , Hoshino Yu , Miura Yoshiko , Murakami Tatsuya
Published: October 2014

A catalytic membrane reactor, which was immobilized with palladium‐loaded nanogel particles (NPs), was developed for continuous‐flow Suzuki coupling reaction. Palladium‐loaded membranes were prepared by immobilization of NPs, adsorption of palladium ions, and reduction into palladium(0). The presence of palladium in the membrane was confirmed by the scanning electron microscopy; palladium aggregation was not observed. The catalytic activity of the membrane reactor in continuous‐flow Suzuki coupling reaction was approximately double that of a comparable reactor in which palladium ions were directly adsorbed onto an aminated membrane. This was attributed to the formation of small palladium particles. The reusability in the continuous‐flow system was higher than that in a batch system, and the palladium‐loaded membrane reactor had high long‐term stability. © 2014 American Institute of Chemical Engineers AIChE J, 61: 582–589, 2015
Formation of a Dimer of Trinuclear Helicates which Encapsulates an Array of Six Hydrogen‐Bonded Anions
Authors: Faulkner Robert A. , Harding Lindsay P. , Higginson Joshua , Rice Craig R. , Slater Christopher
Published: October 2014

The amine‐containing ligand L, composed of two bidentate pyridyl‐thiazole moieties linked by a 1,3‐diaminophenylene unit, reacts with copper(II) ions to form a dinuclear double helicate [Cu2L2]4+. Reaction of [Cu2L2]4+ with dihydrogen phosphate (0.5 equivalents) gives the unsaturated dinuclear double helicate [Cu2L2(OPO3H2)]3+. [Cu2L2(OPO3H2)]3+ further reacts with another 0.5 equivalents of dihydrogen phosphate to give a trinuclear circular helicate which then self‐assembles into a hexameric cluster [{Cu3L3(OPO3H2)3}]26+.
Synthesis of 2‐Aminoquinoline‐3‐carboamides and Pyrimido[4,5‐b]quinolin‐4‐ones through Copper‐Catalyzed One‐pot Multicomponent Reactions
Authors: Zhang Xin‐Ying , Guo Xiao‐Jie , Fan Xue‐Sen
Published: October 2014

Pyrimido[4,5‐b]quinolinones have attracted considerable interest from both chemical and medicinal scientists as these compounds display remarkable antimicrobial, anti‐inflammatory, antitumor, antiallergy, analgesic, and antioxidant activities. The importance of pyrimido[4,5‐b]quinolinones has stimulated enormous efforts to develop efficient methodologies for their synthesis. Herein, we disclose a novel synthetic protocol toward pyrimido[4,5‐b]quinolin‐4‐ones through Cu(OAc)2‐catalyzed one‐pot four‐component reactions of 2‐bromobenzaldehydes, aqueous ammonia, cyanoacetamides and aldehydes. The synthetic procedure combines amination/condensation/cyclization/dehydrogenation reactions in one pot, allowing synthesis of complex compounds in a simple and practical manner. Compared with literature procedures, the synthetic strategies developed herein showed advantages such as readily available and economically sustainable starting materials, structural diversity of products, good functional group tolerance, and a remarkably simple operation process.
Genetic basis of delay discounting in frequent gamblers: examination of a priori candidates and exploration of a panel of dopamine‐related loci
Authors: Gray Joshua C. , MacKillop James
Published: October 2014

Introduction

Delay discounting is a behavioral economic index of impulsivity that reflects preferences for small immediate rewards relative to larger delayed rewards. It has been consistently linked to pathological gambling and other forms of addictive behavior, and has been proposed to be a behavioral characteristic that may link genetic variation and risk of developing addictive disorders (i.e., an endophenotype). Studies to date have revealed significant associations with polymorphisms associated with dopamine neurotransmission. The current study examined associations between delay discounting and both previously linked variants and a novel panel of dopamine‐related variants in a sample of frequent gamblers.

Methods

Participants were 175 weekly gamblers of European ancestry who completed the Monetary Choice Questionnaire to assess delay discounting preferences and provided a DNA via saliva.

Results

In a priori tests, two loci previously associated with delayed reward discounting (rs1800497 and rs4680) were not replicated, however, the long form of DRD4 VNTR was significantly associated with lower discounting of delayed rewards. Exploratory analysis of the dopamine‐related panel revealed 11 additional significant associations in genes associated with dopamine synthesis, breakdown, reuptake, and receptor function (DRD3, SLC6A3, DDC, DBH, and SLC18A2). An aggregate genetic risk score from the nominally significant loci accounted for 17% of the variance in discounting. Mediational analyses largely supported the presence of indirect effects between the associated loci, delay discounting, and pathological gambling severity.

Conclusions

These findings do not replicate previously reported associations but identify several novel candidates and provide preliminary support for a systems biology approach to understand the genetic basis of delay discounting.
Chondrogenic differentiation of ChM‐I gene transfected rat bone marrow‐derived mesenchymal stem cells on 3‐dimensional poly (L‐lactic acid) scaffold for cartilage engineering
Authors: Xing Shuang‐Chun , Liu Yang , Feng Y. , Jiang Chen , Hu Yu‐Qiang , Sun Wei , Wang Xin‐Hui , Wei Zhi‐Yong , Qi Min , Liu Jing , Zhai Li‐Jie , Wang Zhi‐Qiang
Published: October 2014

We have explored the role of Chondromodulin‐I (ChM‐I) in chondrogenesis of bone marrow‐derived mesenchymal stem cells (BMSCs) in 3‐dimensional (3D) scaffold for cartilage tissue engineering. BMSCs of Sprague Dawley (SD) rats were cultured on poly‐(L‐lactic acid) [PLLA] scaffolds with different pore sizes (80–200 μm, 200–450 μm) with or without surface modification by chitosan. Cell viability, proliferation, and morphology were measured using confocal microscope and the CCK‐8 method. Untransfected BMSCs, BMSCs expressing pcDNA3.1(+), BMSCs expressing plasmid pcDNA3.1 (+)/ChM‐I were cultured on 3D scaffolds in standard growth medium or transforming growth factor‐β1 (TGF‐β1) supplemented chondrogenic induction mediumin vitrofor 3 weeks and the expression of collagen type II was determined. Cell‐scaffolds constructs were implanted subcutaneously for 3 monthsin vivo. BMSCs had a higher viability and proliferation in PLLA scaffolds of pore size 200–450 μm than that of 80–200 μm, and surface modification with chitosan did not enhance cell attachment. The ChM‐I gene enhanced chondrogenesis and increased collagen type II synthesis. Immunohistochemistry fromin vivostudy showed enhanced cartilage regeneration in BMSCs expressing pcDNA3.1 (+)/ChM‐I on 3D PLLA scaffolds. It also demonstrated that TGF‐β1 might promote chondrogenesis of rat BMSCs by synergizing with the ChM‐I gene. ChM‐I could be beneficial to future applications in cartilage repair.
Geniposide protects pancreatic INS‐1E β cells from hIAPP‐induced cell damage: Potential involvement of insulin degrading‐enzyme
Authors: Zhang Yonglan , Yin Fei , Liu Jianhui , Wang Yanwen
Published: October 2014

Islet amyloid deposition is increasingly seen as a pathogenic feature of type 2 diabetes mellitus (T2DM), with the deposits containing the unique amyloidogenic peptide islet amyloid polypeptide (IAPP, also known as amylin). The fibril precursors of IAPP contribute to its cytotoxicity on pancreatic β cells and be important in causing β‐cell dysfunction in T2DM. However, the development of effective this study, inhibitors against the toxicity of IAPP has been extremely challenging. We have found that pre‐incubation with geniposide dose‐dependently prevented human IAPP (hIAPP)‐induced cell damage in INS‐1E cells, and bacitracin, an inhibitor of IDE activity, prevented significantly the protective effects of geniposide in pancreatic INS‐1E cells significantly. Geniposide induced the expression of insulin‐degrading enzyme (IDE), a key degrading protein of hIAPP, but had no significant effect on the aggregation of hIAPP. These findings indicate that geniposide prevents hIAPP‐induced cytotoxicity in INS‐1E cells involving upregulation of IDE expression.
ChemInform Abstract: Crystal Structure of Alluaudite‐Type Na4Co(MoO4)3.
Authors: Nasri Rawia , Bourguiba Noura Fakhar , Zid Mohamed Faouzi , Driss Ahmed
Published: October 2014

Na4Co(MoO4)3 is prepared by solid state reaction of Na2CO3, Co(NO3)2, and (NH4)2MoO4 in air (Na:Co:Mo = 3:1:3; porcelain crucible, 673 K, 1 d).
ChemInform Abstract: On the Crystal Structure and Physical Properties of the UFeSb2 Compound.
Authors: Goncalves A. P. , Henriques M. S. , Waerenborgh J. C. , Curlik I. , Il'kovic S. , Reiffers M.
Published: October 2014

The title compound is synthesized by arc‐melting of the elements followed by annealing at 750 °C (7 d) and characterized by powder XRD, Moessbauer spectroscopy, electrical resistivity, magnetization, and specific heat measurements.
ChemInform Abstract: Ba3GeS5 and Ba3InS4Cl: Interesting Size Effects Originated from the Tetrahedral Anions.
Authors: Pan Ming‐Yan , Xia Sheng‐Qing , Liu Xiao‐Cun , Tao Xu‐Tang
Published: October 2014

The new compounds Ba3GeS5 (I) and Ba3InS4Cl (II) are prepared by solid state reactions of BaCl2, BaS, and GeS or In2S3 with a small excess of BaCl2 as the flux (graphite crucible in evacuated silica tube, 1000 °C, 30 h).
ChemInform Abstract: One‐Dimensional Molybdenum Thiochlorides and Their Use in High Surface Area MoSx Chalcogels.
Authors: Islam Saiful M. , Subrahmanyam Kota S. , Malliakas Christos D. , Kanatzidis Mercouri G.
Published: October 2014

The new compounds α‐ and β‐MoSCl3 and MoSeCl3 are prepared by chemical vapor transport reaction of MoCl3 and elemental S or Se (sealed silica tubes, 48 h, 400 → 200 °C for α‐MoSCl3 and MoSeCl3 and 400 → 140 °C for β‐MoSCl3).
ChemInform Abstract: Structural, Magnetic and Transport Properties of 2D Structured Perovskite Oxychalcogenides.
Authors: Berthebaud David , Lebedev Oleg I. , Pelloquin Denis , Maignan Antoine
Published: October 2014

Ca2CuFeO3S, Sr2CuFeO3S, and the new compound Sr2CuFeO3Se are synthesized by solid state reactions using SrSe or SrS, SrO2, Cu, FeO, CaO, and S as starting materials (850 °C, 10 h).
ChemInform Abstract: Enantioselective Reduction of Prochiral Ketones with NaBH4/Me2SO4/(S)‐Me‐CBS.
Authors: Zhou Yuhan , Gao Guchao , Song Yuming , Qu Jingping
Published: October 2014

Borane, generated in situ via reaction of NaBH4 with DMSO, is successfully applied to reduce prochiral ketones.
ChemInform Abstract: Regioselectivity of Intramolecular Rhodium‐Catalyzed C—H Insertion Reactions of α‐Aryl‐α‐diazocarboxylates: Influence of the Aryl Substituent.
Authors: Wamser Maximilian , Bach Thorsten
Published: October 2014

While phenyl‐substituted substrates (I) yield cis‐configured γ‐lactones under the presented reaction conditions, ortho‐bromo‐phenyl‐substituted substrates (IV) yield trans‐configured β‐lactones instead.
ChemInform Abstract: Mild and Chemoselective Lactone Ring‐Opening with (TMS)ONa. Mechanistic Studies and Application to Sweroside Derivatives.
Authors: Lemoine Hugues , Markovic Dean , Deguin Brigitte
Published: October 2014

The lactone ring opening allows a straightforward access to various hydroxy carboxylic acids including polyfunctionalized secoiridoid derivatives.
ChemInform Abstract: Heterogeneous Platinum Catalytic Aerobic Oxidation of Cyclopentane‐1,2‐diols to Cyclopentane‐1,2‐diones.
Authors: Reile Indrek , Kalle Sigrid , Werner Franz , Jaerving Ivar , Kudrjashova Marina , Paju Anne , Lopp Margus
Published: October 2014

The aerobic oxidation of cyclopentane‐1,2‐diols is conducted under air.
ChemInform Abstract: Catalytic Acceptorless Dehydrogenations: Ru‐Macho Catalyzed Construction of Amides and Imines.
Authors: Oldenhuis Nathan J. , Dong Vy M. , Guan Zhibin
Published: October 2014

A ruthenium(II) PNP type pincer catalyst promotes formation of amides and imines from alcohols and amines via an acceptorless dehydrogenation pathway.
ChemInform Abstract: Asymmetric Hydrogenation Reactions with Rh and Ru Complexes Bearing Phosphine—Phosphites with an Oxymethylene Backbone.
Authors: Kleman Patryk , Vaquero Monica , Arribas Inmaculada , Suarez Andres , Alvarez Eleuterio , Pizzano Antonio
Published: October 2014

The title ligands show good activity in Rh‐catalyzed hydrogenation reactions of olefinic substrates giving the corresponding products with enantioselectivities up to 96% enantiomeric excess.
ChemInform Abstract: Rhodium‐Catalyzed Transfer Hydrogenation with Aminophosphines and Analysis of Electrical Characteristics of Rhodium(I) Complex/n‐Si Heterojunctions.
Authors: Aydemir Murat , Ocak Yusuf Selim , Rafikova Khadichakhan , Kystaubayeva Nurzhamal , Kayan Cezmi , Zazybin Alexey , Ok Fatih , Baysal Akin , Temel Hamdi
Published: October 2014

The shown catalyst gives excellent conversions and shows the highest turnover frequencies.
ChemInform Abstract: NHC—Copper Hydrides as Chemoselective Reducing Agents: Catalytic Reduction of Alkynes, Alkyl Triflates, and Alkyl Halides.
Authors: Cox Nick , Dang Hester , Whittaker Aaron M. , Lalic Gojko
Published: October 2014

Highly chemoselective NHC—copper‐catalyzed reductions of unactivated terminal and internal alkynes, as well as of primary alkyl triflates and primary and secondary alkyl halides are described.
ChemInform Abstract: Copper‐Catalyzed Electrophilic Amination of Heteroarenes and Arenes by C—H Zincation.
Authors: McDonald Stacey L. , Hendrick Charles E. , Wang Qiu
Published: October 2014

A broader substrate scope for direct heteroarene amination is achieved by C—H zincation and subsequent Cu‐catalyzed electrophilic amination.
ChemInform Abstract: TBAOH Mediated: An Efficient and Simple Procedure for Alkylation of Alcohols, Phenols and Thiols under Neat Aqueous Conditions.
Authors: Soleiman‐Beigi Mohammad , Kazemi Mosstafa , Aryan Reza , Shiri Lotfi
Published: October 2014

Bu4NOH is used as strong base, reaction medium, and phase transfer reagent.
ChemInform Abstract: Synthesis and Characterization of Novel Chiral Bidentate P,N‐Containing Ligands and Ruthenium(II) Complex. The Application in Asymmetric Transfer Hydrogenation of Ketones.
Authors: Zeng Li , Wu Fang , Li Yan‐Yun , Dong Zhen‐Rong , Gao Jing‐Xing
Published: October 2014

The applied catalyst is prepared in four steps.
ChemInform Abstract: Three in the Spotlight: Photoinduced Stereoselective Synthesis of (Z)‐Acyloxyacrylamides Through a Multicomponent Approach.
Authors: Garbarino Silvia , Banfi Luca , Riva Renata , Basso Andrea
Published: October 2014

The synthesis of the title compounds in an operational simple reaction from a variety of diazoketones, isocyanides and carboxylic acids is presented.
ChemInform Abstract: Copper‐Catalyzed Decarboxylative C—N Triple Bond Formation: Direct Synthesis of Benzonitriles from Phenylacetic Acids under O2 Atmosphere.
Authors: Feng Qiang , Song Qiuling
Published: October 2014

The methodology is environmentally friendly and tolerates numerous functional groups.
ChemInform Abstract: Gold‐Catalyzed Intermolecular C—S Bond Formation: Efficient Synthesis of α‐Substituted Vinyl Sulfones.
Authors: Xi Yumeng , Dong Boliang , McClain Edward J. , Wang Qiaoyi , Gregg Tesia L. , Akhmedov Novruz G. , Petersen Jeffrey L. , Shi Xiaodong
Published: October 2014

The first gold‐catalyzed Markovnikov addition of sulfinic acids to terminal alkynes is presented.
ChemInform Abstract: Nickel‐Catalyzed Cross‐Coupling of Aryl Fluorides and Organozinc Reagents.
Authors: Zhu Feng , Wang Zhong‐Xia
Published: October 2014

It is found that NiCl2(PCy3)2 efficiently promotes the reaction of aromatic fluorides with organozinc reagents generated from ZnCl2 and alkyl‐ or aryllithium.