bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical Characterization of Yellow and Orange Pollen (Helianthus annuus) and its Effect in the Growth of Hydroxyapatite
Authors: Sánchez Juárez D.L. , Martínez Montes G. , Rubio Rosas E.
Published: April 2013

In this work orange pollen grains (Helianthus annuus) were immersed in a supersaturated ionic solution (similar to human extracellular fluid) during different times at 37 °C, atmospheric pressure and pH of 7.4. By Fourier transform infrared spectroscopy (FT-IR) we confirmed the presence of the functional groups carbonyl, amide I, amide II, carboxyl and phosphate in both samples. Nevertheless, yellow pollen owns a greater amount of phosphate groups than orange pollen. By scanning electron microscopy (SEM), differences in the morphology, shape and size of both samples were not observed. In orange pollen grains, amorphous agglomerates can be observed for periods smaller to 14 days and spherical structures formed by nanocrystals of laminar form were observed on their surface at 17 days. By energy dispersive spectroscopy (EDS) confirms the presence of calcium and phosphorous in the agglomerates with different Ca/P ratio and by X-ray diffraction (XRD) the hydroxyapatite (HAp) phase was verified.
Microstructural Behavior during Bonding of Alumina to Niobium by Liquid State Diffusion
Authors: Alonso-Santos Julieta , Téllez-Arias Mercedes G. , Bedolla Egberto , Lemus-Ruiz José
Published: April 2013

The objective of this work was to study various aspects of liquid state diffusion bonding of cylindrical samples of Al2O3 and commercially pure niobium (99.7%) by brazing using a 25 µm thick 70Cu-30Zn (wt%) alloy as joining element. Initially, sintering of alumina powder was carried out in order to produce a 7 mm diameter samples at 1550°C by 120 minutes. Joining experiments were carried out on Al2O3/Cu-Zn/Nb/Cu-Zn/Al2O3 sandwich-like combinations at temperature of 920°C, 950°C and 980°C using different holding times under argon (Ar) atmosphere. The experimental results show a successful joining of alumina to niobium at 950°C and 980°C, however not at 920°C. Joining of Al2O3/Cu-Zn/Nb/Cu-Zn/Al2O3 occurred by the formation of a homogeneous diffusion zone with no interfacial cracking or porosity at the interface. Scanning electron microscopy (SEM) micrographs show the layer formed in the reaction zone. It was observed that the width of the reaction zone increases with bonding temperature and time. Electron probe microanalysis (EPMA) revealed that at any particular bonding temperature, Nb travel into the Cu-Zn joining element forming a circular precipitate phase near to the alumina ceramic.
Effects of Welding Conditions by TIG and Post Weld Heat Treatment in Ductile Cast Iron on the Corrosion Resistance
Authors: Gaxiola Peralta A.J. , Pérez-López M.J. , Almanza Casas E.
Published: April 2013

In this study ductile cast iron plates were welded by tungsten inert gas process (TIG). The objective was to evaluate the effect of filler metals; current welding and post weld heat treatment (PWHT) on the microstructure and corrosion resistance of joints. Metallographic examination of welded plates showed three different zones: fusion zone with a dendritic structure, heat affected zone with mixture of martensite and ledeburite structure and ferritic-pearlitic structure in base metal. Microstructure of welded area changes drastically to acicular ausferrite when the PWHT was applied. Corrosion rates values of 4.5 mpy were obtained in plates welded with E-FeNiCI filler metal and current of 125 and 150 A; this value is approximately half of the ones obtained in the ductile cast iron (10.5 mpy). These results are associated with: a good chemical compatibility of the filler material and ductile cast iron, increases of Ni content, refinement of the structure and a higher dissolution of graphite nodules that mitigate graphitic corrosion mechanism. The PWHT plates showed a slightly decrease in corrosion rates. In particular, plates welded with E-FeNiCI filler material and 125 A of current intensities exhibited the best corrosion resistance (3.75 mpy). This phenomenon can be attributed to homogenization of nickel in the weld bead forming passive layers that increase the corrosion resistance.
High-Energy Ball-Milling of FeAl2 and Fe2Al5 Intermetallic Systems
Authors: Romero-Romero J.R. , López-Miranda J. Luis , Esparza Muñoz Rodrigo Alonso , Espinosa-Medina M.A. , Rosas G.
Published: April 2013

In this study, FeAl2 and Fe2Al5 intermetallic alloys were prepared by conventional casting technique. In order to study their structural stability the alloys were subjected to high-energy ball milling process for 1, 2.5, 5 and 10 h. The structural and chemical characterizations were conducted by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and differential scanning calorimetry. After 10 h of milling, the experimental results indicated a phase transformation from FeAl2-triclinic phase to Fe2Al5-ortorrombic structure. This phase transformation is characterized by a change from low to high symmetry systems.
Lysine 313 of T-box Is Crucial for Modulation of Protein Stability, DNA Binding, and Threonine Phosphorylation of T-bet
Authors: Jang Eun Jung , Park Hye Ryeon , Hong Jeong-Ho , Hwang Eun Sook
Published: April 2013

A T-box–containing protein expressed in T cells (T-bet) is a key transcription factor involved in the regulation of Th cell differentiation. Although T-bet–deficient CD4+ T cells fail to produce IFN-γ and typically differentiate into Th2 cells in vitro, ectopic overexpression of T-bet elevates IFN-γ and suppresses production of IL-2 and Th2 cytokines through different mechanisms. Despite the importance of the T-bet protein level, the regulatory mechanisms that control T-bet protein stability are largely unknown. In this study, we found that T-bet underwent proteasomal degradation via ubiquitination at Lys-313. Despite its robust accumulation following lysine mutation, T-betK313R failed to increase IFN-γ production because of diminished DNA binding activity, as demonstrated in the crystal structure of T-bet–DNA complex. Strikingly, T-betK313R entirely lost the ability to suppress IL-2 production and Th2 cell development; this was due to loss of its interaction with NFAT1. We further identified that the T-betK313R reduced the phosphorylation of T-bet at Thr-302, and that threonine phosphorylation was essential for T-bet interaction with NFAT1 and suppression of NFAT1 activity. Retroviral transduction of T-betT302A into T-bet–deficient cells restored IFN-γ levels compared with those induced by wild-type T-bet, but this mutant failed to inhibit IL-2 and Th2 cytokine production. Collectively, these data show that Lys-313 in the T-box domain is essential for controlling T-bet protein stability via ubiquitin-dependent degradation, T-bet binding to the IFN-γ promoter, and for the interaction with and suppression of NFAT1. Thus, multiple posttranslational modifications of T-bet are involved in fine-tuning cytokine production during Th cell development.
Rational Engineering of a Minimized Immune Inhibitor with Unique Triple-Targeting Properties
Authors: Schmidt Christoph Q. , Bai Hongjun , Lin Zhuoer , Risitano Antonio M. , Barlow Paul N. , Ricklin Daniel , Lambris John D.
Published: April 2013

Inadequate control of the complement system is the underlying or aggravating factor in many human diseases. Whereas treatment options that specifically target the alternative pathway (AP) of complement activation are considered highly desirable, no such option is available in the clinic. In this study, we present a successful example of protein engineering, guided by structural insight on the complement regulator factor H (FH), yielding a novel complement-targeted therapeutic (mini-FH) with clinical potential. Despite a 70% reduction in size, mini-FH retained and in some respects exceeded the regulatory activity and cell surface–recognition properties of its parent protein FH, including the recently described recognition of sites of oxidative stress. Importantly, the chosen design extended the functional spectrum of the inhibitor, as mini-FH showed increased binding to the surface-bound opsonins iC3b and C3dg when compared with FH. Thus, mini-FH is equipped with a unique and clinically valuable triple-targeting profile toward diseased host cells, through its binding to sites of ongoing complement activation, markers of oxidative damage, and host surface-specific polyanions. When assessed in a clinically relevant AP-mediated disease model of paroxysmal nocturnal hemoglobinuria, mini-FH largely outperformed FH and indicated advantages over clinically evaluated AP inhibitors. Thus, the rational engineering of a streamlined FH construct not only provided insight into the function of a key complement regulator, but also yielded a novel inhibitor that combines a triple-targeting approach with high AP-specific inhibitory activity (IC50 ∼ 40 nM), which may pave the way toward new options for the treatment of complement-mediated diseases.
The brand image and performance of small and medium enterprises: How can social responsibility activities help?
Authors: Rootman Chantal , Zeka Bomikazi
Published: April 2013

Orientation: Business social responsibility (BSR) activities may lead to benefits for small and medium enterprises (SMEs).Research purpose: To investigate how SMEs could use BSR activities to improve their brand image and business performance.Motivation for the study: In a competitive environment, SMEs face various challenges such as financial constraints, lack of resources or lack of managerial experience. BSR activities pave the way for an SME to make a positive contribution toward the environment in which it operates, as they indicate a level of care for the natural environment and show commitment toward the upliftment of communities. The benefits that accrue to SMEs that engage in BSR activities are yet to be determined and the need for research on SMEs’ BSR activities and results led to this study.Research design, approach and method: Structured questionnaires were distributed to 320 SMEs in the Eastern Cape, South Africa. A total of 200 usable questionnaires were received, obtaining a response rate of 62.5%, and these were analysed quantitatively.Main findings: Significant relationships were found between three BSR activities, namely stakeholder relations, community development and environmental awareness, and the SME’s brand image; as well as between the SME’s brand image and business performance.Practical and managerial implications: Implemented BSR recommendations may lead to improved brand images and business performance; and therefore an increased success rate amongst SMEs in South Africa.Contribution and value-add: BSR research has predominantly been in the sphere of larger and more established enterprises. The study suggests practical recommendations to SMEs to improve their brand image and business performance by employing BSR strategies relating to stakeholder relations, community development and environmental awareness.
Impact of climate change scenarios on Canadian agroclimatic indices
Authors: Qian Budong , De Jong Reinder , Gameda Sam , Huffman Ted , Neilsen Denise , Desjardins Raymond , Wang Hong , McConkey Brian
Published: April 2013

Qian, B., De Jong, R., Gameda, S., Huffman, T., Neilsen, D., Desjardins, R., Wang, H. and McConkey, B. 2013. Impact of climate change scenarios on Canadian agroclimatic indices. Can. J. Soil Sci. 93: 243–259. The Canadian agricultural sector is facing the impacts of climate change. Future scenarios of agroclimatic change provide information for assessing climate change impacts and developing adaptation strategies. The goal of this study was to derive and compare agroclimatic indices based on current and projected future climate scenarios and to discuss the potential implications of climate change impacts on agricultural production and adaptation strategies in Canada. Downscaled daily climate scenarios, including maximum and minimum temperatures and precipitation for a future time period, 2040–2069, were generated using the stochastic weather generator AAFC-WG for Canadian agricultural regions on a 0.5°×0.5° grid. Multiple climate scenarios were developed, based on the results of climate change simulations conducted using two global climate models – CGCM3 and HadGEM1 – forced by IPCC SRES greenhouse gas (GHG) emission scenarios A2, A1B and B1, as well as two regional climate models forced by the A2 emission scenario. The agroclimatic indices that estimate growing season start, end and length, as well as heat accumulations and moisture conditions during the growing season for three types of field crops, cool season, warm season and over-wintering crops, were used to represent agroclimatic conditions. Compared with the baseline period 1961–1990, growing seasons were projected to start earlier, on average 13 d earlier for cool season and over-wintering crops and 11 d earlier for warm season crops. The end of the growing season was projected on average to be 10 and 13 d later for over-wintering and warm season crops, respectively, but 11 d earlier for cool season crops because of the projected high summer temperatures. Two indices quantifying the heat accumulation during the growing season, effective growing degree days (EGDD) and crop heat units (CHU) indicated a notable increase in heat accumulation: on average, EGDD increased by 15, 55 and 34% for cool season, warm season and over-wintering crops, respectively. The magnitudes of the projected changes were highly dependent on the climate models, as well as on the GHG emission scenarios. Some contradictory projections were observed for moisture conditions based on precipitation deficit accumulated over the growing season. This confirmed that the uncertainties in climate projections were large, especially those related to precipitation, and such uncertainties should be taken into account in decision making when adaptation strategies are developed. Nevertheless, the projected changes in indices related to temperature were fairly consistent.
NH3 volatilization, soil concentration and soil pH following subsurface banding of urea at increasing rates
Authors: Rochette Philippe , Angers Denis A. , Chantigny Martin H. , Gasser Marc-Olivier , MacDonald J. Douglas , Pelster David E. , Bertrand Normand
Published: April 2013

Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH 3 volatilization, soil [Formula: see text] concentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH3) emissions following a local increase in soil ammonium ([Formula: see text]) concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH3 volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m−1. Ammonia volatilization (wind tunnels), and soil [Formula: see text] concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH3. Cumulative NH3-N emissions were closely related (R 2≥0.85) to maximum increases in soil [Formula: see text] concentration and pH, and their combined influence likely contributed to the nonlinearity of the volatilization response to urea application rate. However, the rapid increase in NH3 losses when soil pH rose above 7 suggests that soil pH was the main factor explaining the nonlinear response of NH3 volatilization. When compared with previous studies, our results suggest that the response of NH3 volatilization losses to urea application rate in acidic soils are controlled by similar factors whether urea is broadcasted at the soil surface or subsurface banded.
Serpentine affected soils and the formation of magnesium phosphates (struvite)
Authors: Baugé S. M. Y. , Lavkulich L. M. , Schreier H. E.
Published: April 2013

Baugé, S. M. Y., Lavkulich, L. M. and Schreier, H. E. 2013. Serpentine affected soils and the formation of magnesium phosphates (struvite). Can. J. Soil Sci. 93: 161–172. The Sumas River watershed, located in the intensive agricultural region of the Lower Fraser Valley of British Columbia (Canada), contains serpentine asbestos from a natural landslide. Serpentinic soils have a high Mg to Ca ratio that can affect soil fertility, including soil-solution P relations. The objectives of the study were: (i) to evaluate some common methods of estimating plant available phosphorus in the surface horizons of the serpentine-affected soils and those receiving large quantities of livestock manure, and (ii) to determine if there is evidence for the formation of soluble Mg phosphates, e.g., struvite, a meta-stable P phase in these soils. Seven soil nutrient extractants were used to determine major and minor elemental concentrations. Acid ammonium oxalate, 1 M HCl and Bray P1 extractions were most effective for measuring available phosphorus in these soils. Manure and fertilizer applications appear to favor the formation of Mg-phosphates, and are considered to be more soluble in terms of phosphorus than either calcium-phosphates or aluminum/iron-phosphates. X-ray diffraction, scanning electron microscopy and nuclear magnetic resonance examinations gave positive evidence for the presence of struvite in the soils.
A comparison of three colorimetric methods of ferrous and total reactive iron measurement in freshwaters
Authors: Verschoor Mark J. , Molot Lewis A.
Published: April 2013

The measurement of low levels of ferrous and total reactive iron (TRFe) using three common colorimetric methods (bathophenanthroline (BPA), triazine (TPTZ), and ferrozine) in freshwater was evaluated. The BPA method, due to a hexanol extraction step, had unacceptably high limits of detection with small sample volumes. Humic matter also interfered by forming a precipitate. Although ferrozine&s limit of detection was lower, recovery of Fe spikes by TPTZ was much higher in samples with high levels of colored dissolved organic carbon (CDOC) at pH 6 (90 versus 60%) using the standard development time of 10 min because the iron reduction rate is much slower with ferrozine, which requires 1 hr. Recovery of spiked Fe at sample pH 9 was very poor (32 versus 39%). TPTZ with ascorbic acid in samples adjusted to pH 6 is recommended for TRFe analysis. In the absence of a reducing agent and CDOC, TPTZ reagents reduce ferric to ferrous iron (autoreduction), whereas ferrozine has negligible autoreducing properties. CDOC produced significant autoreducing effects using either TPTZ or ferrozine methods, leading to overestimates unless measured immediately upon reagent addition. Hence, immediate measurement with ferrozine is most suitable for ferrous. Ascorbic acid reduces more rapidly than hydroxylamine and does not need to be purified.
Enfoques da informação presentes em diferentes publicações periódicas brasileiras da área de Ciência da Informação
Authors: Vanti Nadia Aurora , Nascimento Bruna Laís , Felipe Carla Beatriz
Published: April 2013

Mapeamento dos enfoques sobre informação presentes em diferentes publicações periódicas brasileiras da área de Ciência da Informação a partir de três orientações conceituais: Informação para negócios, Informação para a cidadania e Informação para a emancipação. Utiliza-se como metodologia a pesquisa bibliográfica, a pesquisa qualitativa e quantitativa. Conclui-se que o conceito de informação adotado nos artigos analisados varia conforme a orientação teórica abordada pelos autores, sendo que para cada uma delas é utilizado um conjunto de termos que a identifica. Também foi possível constatar que o enfoque mais presente nos periódicos analisados é Informação para negócios.
Gestão da informação em bibliotecas universitárias: as práticas do Sistema de Bibliotecas da Universidade Federal de Goiás (Sibi/UFG)
Authors: Ferreira Luciana Alves , Maia Luiz Cláudio Gomes
Published: April 2013

Esta pesquisa descritiva e exploratória objetivou verificar se as atuais práticas de gestão da informação do Sistema de Bibliotecas da Universidade Federal de Goiás (Sibi/UFG) atendem às necessidades de informação dos usuários da área de saúde, dos cursos de graduação e pós-graduação (Stricto sensu) em Biomedicina e Enfermagem. Para tanto, utilizou-se o modelo de gerenciamento da informação proposto por Choo e realizou-se um estudo de usuário em relação ao uso da Biblioteca Virtual em Saúde da BIREME. Concluiu-se que a gestão da informação no Sibi/UFG é relativamente capaz de atender às necessidades de informação dos usuários dos cursos de Biomedicina e Enfermagem.
Biblioterapia na Ciência da Informação: Comunicação e Mediação
Authors: Guedes Mariana Giubertti , Baptista Sofia Galvão
Published: April 2013

O artigo apresenta uma reflexão crítica sobre a Biblioterapia como objeto de estudo da Ciência da Informação (CI), tendo nesta perspectiva, avaliação das características intrínsecas da Biblioterapia dentro da fundamentação da CI, destacando aspectos cognitivos, sociais e interdisciplinares. Pela aplicação variada, a Biblioterapia tem várias definições indicadas no artigo, sendo analisado seu processo no ponto de vista de diversos autores. Analisam-se princípios da Ciência da Informação e do processo comunicacional para a comparação com a Biblioterapia. Neste contexto, destaca-se a atuação biblioterapêutica como uma forma de comunicação e mediação da informação, sendo avaliado o processo comunicacional (seleção, leitura e interpretação de textos com indivíduos) e o profissional mediador (biblioterapêuta).
Le systeme d’information des reseaux de sante: la reorganisation de la medecine en e-sante
Authors: Margueritte Maryline , Gonzales-Aguilar Audilio
Published: April 2013

Les réseaux de santé ont développé depuis plusieurs années des dispositifs permettant une prise en charge coordonnée des patients en France, tant sur les plans médical que médico-psycho-social et humain. Certains ont développé des dossiers de santé partagés informatisés permettant la mise en commun d’informations utiles à la coordination et à la continuité des soins. Depuis 2009 avec la réforme de l’hôpital on veut installer des modes de fonctionnement coopératifs entre les professionnels et avec les usagers du système de santé. La mise en œuvre d’un système d’information de santé pour assurer d’une part, la transversalité du processus métier avec le patient et d’autre part pouvoir mesurer les résultats médicaux et économiques de cette évolution d’un système complexe d’information. Dans ce contexte, les possibilités offertes par les technologies de l’information et de la communication (TIC) permettent la mise en place d’applications favorisant une augmentation de la participation « on line » des citoyens. Le « virage ambulatoire » exporte la santé hors des murs. C’est une médecine innovante qui permet au patient de rester dans son « chez soi ». En France, ce re-engeneering repose sur quatre domaines : un dossier médical informatisé, une prise en charge collective par les professions médicales et paramédicales, une autonomisation et une mise en réseau du secteur de santé.
A three-dimensional variational data assimilation system for multiple aerosol species with WRF/Chem and an application to PM2.5 prediction
Authors: Li Z. , Zang Z. , Li Q. B. , Chao Y. , Chen D. , Ye Z. , Liu Y. , Liou K. N.
Published: April 2013

Abstract. A three-dimensional variational data assimilation (3-DVAR) algorithm for aerosols in a WRF/Chem model is presented. The WRF/Chem model uses the MOSAIC (Model for Simulating Aerosol Interactions and Chemistry) scheme, which explicitly treats eight major species (elemental/black carbon, organic carbon, nitrate, sulfate, chloride, ammonium, sodium and the sum of other inorganic, inert mineral and metal species) and represents size distributions using a sectional method with four size bins. The 3-DVAR scheme is formulated to take advantage of the MOSAIC scheme in providing comprehensive analyses of species concentrations and size distributions. To treat the large number of state variables associated with the MOSAIC scheme, this 3-DVAR algorithm first determines the analysis increments of the total mass concentrations of the eight species, defined as the sum of the mass concentrations across all size bins, and then distributes the analysis increments over four size bins according to the background error variances. The number concentrations for each size bin are adjusted based on the ratios between the mass and number concentrations of the background state. Additional flexibility is incorporated to further lump the eight mass concentrations, and five lumped species are used in the application presented. The system is evaluated using the analysis and prediction of PM2.5 in the Los Angeles basin during the CalNex 2010 field experiment, with assimilation of surface PM2.5 and speciated concentration observations. The results demonstrate that the data assimilation significantly reduces the errors in comparison with a simulation without data assimilation and improved forecasts of the concentrations of PM2.5 as well as individual species for up to 24 h. Some implementation difficulties and limitations of the system are discussed.
A 20-day period standing oscillation in the northern winter stratosphere
Authors: Hocke K. , Studer S. , Martius O. , Scheiben D. , Kämpfer N.
Published: April 2013

Abstract. Observations of the ozone profile by a ground-based microwave radiometer in Switzerland indicate a dominant 20-day oscillation in stratospheric ozone, possibly related to oscillations of the polar vortex edge during winter. For further understanding of the nature of the 20-day oscillation, the ozone data set of ERA Interim meteorological reanalysis is analyzed at the latitude belt of 47.5° N and in the time from 1979 to 2010. Spectral analysis of ozone time series at 7 hPa indicates that the 20-day oscillation is maximal at two locations: 7.5° E, 47.5° N and 60° E, 47.5° N. Composites of the stream function are derived for different phases of the 20-day oscillation of stratospheric ozone at 7 hPa in the Northern Hemisphere. The streamline at Ψ = −2 × 107 m2 s−1 is in the vicinity of the polar vortex edge. The other streamline at Ψ = 4 × 107 m2 s1 surrounds the Aleutian anticyclone and goes to the subtropics. The composites show 20-day period standing oscillations at the polar vortex edge and in the subtropics above Northern Africa, India, and China. The 20-day period standing oscillation above Aral Sea and India is correlated to the strength of the Aleutian anticyclone.
How should sparse marine in situ measurements be compared to a continuous model: an example
Authors: de Mora L. , Butenschön M. , Allen J. I.
Published: April 2013

Abstract. This work demonstrates an example of the importance of an adequate method to sub-sample model results when comparing with in situ measurements. A test of model skill was performed by employing a point-to-point method to compare a multi-decadal hindcast against a sparse, unevenly distributed historic in situ dataset. The point-to-point method masked out all hindcast cells that did not have a corresponding in situ measurement in order to match each in situ measurement against its most similar cell from the model. The application of the point-to-point method showed that the model was successful at reproducing the inter-annual variability of the in situ datasets. Furthermore, this success was not immediately apparent when the measurements were aggregated to regional averages. Time series, data density and target diagrams were employed to illustrate the impact of switching from the regional average method to the point-to-point method. The comparison based on regional averages gave significantly different and sometimes contradicting results that could lead to erroneous conclusions on the model performance. Furthermore, the point-to-point technique is a more correct method to exploit sparse uneven in situ data while compensating for the variability of its sampling. We therefore recommend that researchers take into account for the limitations of the in situ datasets and process the model to resemble the data as much as possible.
Transient thermal modeling of permafrost conditions in Southern Norway
Authors: Westermann S. , Schuler T. V. , Gisnås K. , Etzelmüller B.
Published: April 2013

Abstract. Thermal modeling is a powerful tool to infer the temperature regime of the ground in permafrost areas. We present a transient permafrost model, CryoGrid 2, that calculates ground temperatures according to conductive heat transfer in the soil and in the snowpack. CryoGrid 2 is forced by operational air temperature and snow-depth products for potential permafrost areas in Southern Norway for the period 1958 to 2009 at 1 km2 spatial resolution. In total, an area of about 80 000 km2 is covered. The model results are validated against borehole temperatures, permafrost probability maps from "bottom temperature of snow" measurements and inventories of landforms indicative of permafrost occurrence. The validation demonstrates that CryoGrid 2 can reproduce the observed lower permafrost limit to within 100 m at all validation sites, while the agreement between simulated and measured borehole temperatures is within 1 K for most sites. The number of grid cells with simulated permafrost does not change significantly between the 1960s and 1990s. In the 2000s, a significant reduction of about 40% of the area with average 2 m ground temperatures below 0 °C is found, which mostly corresponds to degrading permafrost with still negative temperatures in deeper ground layers. The thermal conductivity of the snow is the largest source of uncertainty in CryoGrid 2, strongly affecting the simulated permafrost area. Finally, the prospects of employing CryoGrid 2 as an operational soil-temperature product for Norway are discussed.
Counterexamples as Starting Points for Reasoning and Sense Making
Authors: Yopp David A.
Published: April 2013

Asked to “fix” a false conjecture, students combine their reasoning and observations about absolute value inequalities, signed numbers, and distance to write true mathematical statements.
Derivative of Area Equals Perimeter—Coincidence or Rule?
Authors: Zazkis Rina , Sinitsky Ilya , Leikin Roza
Published: April 2013

A familiar relationship—the derivative of the area of a circle equals its circumference—is extended to other shapes and solids.
Delving Deeper: The Diver Problem: The Surfer Problem in 3D
Authors: Priest Dean B. , Smith Ronald G. , Carlisle Christin , Mays Rebecca
Published: April 2013

Mathematics is not a “handbag of tricks” but rather a discipline of inquiry and creativity, as Nabb (2010-11) notes, and he has shared his methods and excitement for the inquiry approach. By engaging calculus students in a search for examples of infinite series that meet certain conditions, or arguments that such series do not exist, Nabb appropriately aligns his teaching with the Standards for Mathematical Practice found in the Common Core State Standards (CCSSI 2010). In particular, three Standards for Mathematical Practice come to mind: (a) “make sense of problems and persevere in solving them”; (b) “reason abstractly and quantitatively”; and (c) “model with mathematics” (CCSSI 2010, pp. 6-8).
The Back Page: My Favorite Lesson: The Bulldog Lottery
Authors: Horwitz Kenneth A.
Published: April 2013

Several years ago I became the lead teacher for a newly created statistics course. I wanted the course to emphasize projects that would allow students to apply statistical knowledge to real-world situations. My Bulldog Lottery lesson allows students to apply the concepts of probability and expected value to a real-world phenomenon.
Analysis of Soybean Embryonic Axis Proteins by Two-Dimensional Gel Electrophoresis and Mass Spectrometry
Authors: Savithiry S. Natarajan  , Hari B. Krishnan  , Farooq Khan  , Xi Chen  , Wesley M. Garrett  , Dilip Lakshman
Published: April 2013

A proteomic approach based on two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) for protein separation and subsequent mass spectrometry (MS) for protein identification was applied to establish a proteomic reference map for the soybean embryonic axis. Proteins were extracted from dissected embryonic axes and separated in the first dimension using a pH range from 4-7. A total of 401 protein spots were isolated, digested with trypsin, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We identified 335 protein spots by searching National Center for Biotechnology Information (NCBI) non redundant databases using the Mascot search engine and found a total of 200 unique proteins. Gene Ontology (GO) analysis was employed to understand the molecular processes in which the identified embryonic axes proteins are involved. The majority of proteins play a functional role in catalytic activity (42.9%) and binding (39.3%), followed by nutrient reservoir activity (5.3%), structural molecular activity (4.0%), antioxidant activity (3.2%), transporter activity (2.4%), enzyme regulator activity (1.2%), molecular transducer activity (0.8%), and transcription regulator activity (0.8%). Our 2D-profiling of soybean axis proteins has established for the first time a baseline proteome on which to investigate and compare factors affecting soybean embryonic development and the interaction of beneficial and pathogenic soilborne organisms during seed germination.
Child Abuse: The Human Figure Drawing Test in Evaluating Minors
Authors: Lisi Andrea , Valentina Stallone , Giovanna Tomasino Maria , Valeria Affatati , Grattagliano Ignazio
Published: April 2013

The Human Figure Drawing Test (HFDT) is widely used in clinical and forensic settings. The inappropriate use of this instrument is widespread. This article highlights the expressive and communicative value of children’s drawings in child abuse investigations. The drawings of 3 groups of children (11 certified as abused; 11 suspected of being abused, and 11 certified as non-abused) were examined in order to determine the appropriateness of their use in suspected cases of child abuse. The results of our study appear to be divergent. As of the writing of this article, there is no methodologically correct way in which to utilize this instrument that would reveal specific “graphic indicators of abuse” using the drawings of abused, or presumably abused children.
A Simple Approach to Testing the Potency of Government Purchases to Stimulate Aggregate Demand
Authors: Hatzinikolaou Dimitris
Published: April 2013

Abstract: The paper proposes a new approach to testing the potency of government purchases to stimulate the economy by testing a set of conditions implied by the Ricardian Equivalence (RE) proposition that a typical household incorporates the government's budget constraint into its own. These conditions are as follows: (1) private consumption, income, and government purchases form a â€œlevels relationshipâ€; and (2) considering consumption as the dependent variable, the coefficients of income and of government purchases are 1 and -1. The last restriction is also implied by the hypothesis that consumption and government purchases are perfect substitutes, however, so the proposed approach cannot distinguish between the perfect substitutability and the RE hypotheses. This restriction is thus referred to in the paper as the hypothesis of direct or ex ante full crowding out. If it holds, then the multiplier of government purchases is zero. Using US quarterly data, 1947.1-2012.1, the results suggest that a â€œlevels relationshipâ€ exists and that the coefficient of government purchases is about -0.4 and significantly below -1, thus leading to the conclusion that government purchases stimulate aggregate demand and output.
Fracture Strength of Photovoltaic Silicon Wafers Evaluated Using a Controlled Flaw Method
Authors: Shi Meirong , Youssef Khaled , Rozgonyi George A.
Published: April 2013

Propagation of pre‐existing micro cracks and their associated residual contact stresses, generated from the wafer sawing process, is the leading cause for photovoltaic (PV) silicon wafer/cell breakage during handling and processing. In the current work, the impact of a single micro crack on the fracture strength of PV silicon wafer is investigated based on a controlled flaw method. Radial/median cracks with controllable scales are introduced through microindentation at the center of a PV silicon sample to simulate micro cracks resulting from wafer sawing, handling, or thermal processing. Results indicate that the fracture strength of PV silicon wafer decreases linearly with the increasing of the microindentation load (radial crack scale). In addition, it is found that the impurity carbon plays an important role in the contact cracking‐fracture process. The fracture strength increased ≈21% when the substitutional carbon concentration is increased from 1.2 × 1018 to 6.4 × 1018 cm−3.
Self‐Delivery Multifunctional Anti‐HIV Hydrogels for Sustained Release
Authors: Li Jiayang , Li Xinming , Kuang Yi , Gao Yuan , Du Xuewen , Shi Junfeng , Xu Bing
Published: April 2013

None of the clinical trials of anti‐HIV gels based on conventional polymers or lipid emulsions has been successful, suggesting the need of new molecular design of the anti‐HIV gels. This paper reports the conversion of anti‐HIV prodrugs into self‐delivery supramolecular hydrogels. By covalently conjugating reverse transcriptase inhibitors to a versatile self‐assembly motif, the hydrogelators that self‐assemble to form supramolecular nanofibers as the matrices of hydrogels in a weak acidic condition are obtained. Upon the treatment of prostate acid phosphatase (PAP), the hydrogels exhibit drastically enhanced elasticity. The hydrogelators are biocompatible and able to release the inhibitors under physiological condition. The use of the self‐assembly motif as a self‐delivery agent containing non‐steroid anti‐inflammatory drug (NSAID) renders this hydrogel to be both anti‐inflammatory and anti‐HIV. This work illustrates an unprecedented approach for designing multifunctional supramolecular hydrogels that may serve as potential anti‐HIV hydrogels for sustained drug release.
Novel high porosity mesoporous silica using new mixed two‐block copolymers as a template
Authors: Semsarzadeh Mohammad Ali , Fardi Milad , Khalilian Hamed , Amiri Sahar
Published: April 2013

Mixed block copolymers have been used as a template in the synthesis of new mesoporous silica particles, prepared from sol–gel method. The prominent effect of the block copolymers have been used to provide a new template that controls the surface area and porosity of the particles. Tetraethyl orthosilicate as silica source and two block copolymers, poly(propylene oxide)‐b‐poly(ethylene oxide)‐b‐poly(propylene oxide) and poly(ethylene oxide)‐b‐poly(propylene oxide)‐b‐poly(ethylene oxide) (Pluronics) as a surfactant, were used in water/n‐octane co‐solvent with citric acid catalyst to prepare new nanostructures of mesoporous silica (SPB1 and SPB1,2). The displacement of ethanol with cyclohexanol as a co‐surfactant drastically changed the surface properties of the new mesoporous silica particles (SPB1,2). The surface area, porosity, morphology, and microstructure of particles were characterized by X‐ray diffraction, nitrogen adsorption–desorption, scanning electron microscopy), and transmission electron microscopy. The prepared particles have been specifically characterized for specific use and applications as supporting catalysts for the polymerization of vinyl acetate, drugs delivery, and in the membranes manufacturing based on polyurethanes. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.
Adhesion of grafted polypropylene plates with enzymatically modified chitosan solutions and analysis of failed surfaces by X‐ray photoelectron spectroscopy
Authors: Yamada Kazunori , Naohara Yuki
Published: April 2013

In this study, hydrophilic monomers were photografted onto the PP plates at different monomer concentrations and temperatures, and grafted PP plates were bonded with enzymatically modified chitosan solutions. Their adhesive strength properties were discussed in relation to the grafting conditions and hydrophilic properties such as wettability and water‐absorptivity. In addition, the location of failure was investigated by X‐ray photoelectron spectroscopy analysis of failed surfaces. Wettability of the grafted PP plates except for the PP grafted with acrylic acid (PP‐g‐PAA) plates remained constant above the grafted amounts at which the PP surfaces were fully covered with grafted polymer chains. On the other hand, wettability of the PP‐g‐PAA plates passed through the maximum value and then gradually decreased with the grafted amount probably because of the aggregation of grafted PAA chains. Water‐absorptivity of the grafted layers formed at lower monomer concentrations or temperatures sharply increased at lower grafted amounts. The adhesive strength increased with an increase in the grafted amount and substrate breaking was observed for PP‐g‐PAA plates because enzymatically modified chitosan solutions were successfully penetrated in the grafted layers and quinone derivatives reacted with carboxy groups of grafted PAA chains. Failure occurred in the layers composed of grafted PAA chains and components containing in enzymatically modified chitosan solutions and the location was shifted to the inside of grafted layer, as the grafted amount increased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1369‐1376, 2013
Adaptive Integrated Guidance and Control Based on Backstepping and Input‐to‐State Stability
Authors: Yan Han , Wang Xinghu , Yu Bingfeng , Ji Haibo
Published: April 2013

This paper presents an approach of integrated guidance and control (IGC) design for interception of maneuvering targets (evaders). An IGC model with uncertainties in the pitch plane is formulated, and, by adopting a backstepping scheme, an adaptive nonlinear IGC approach is developed. Theoretical analysis shows that the design approach makes the line‐of‐sight (LOS) rate be input‐to‐state stable (ISS) with respect to target maneuvers and missile model uncertainties, and the stability of the missile dynamics can be guaranteed as well. The numerical simulation confirms the effectiveness of the proposed design approach.
Mixed response surface models and Bayesian analysis of variance components for electrically conductive adhesives
Authors: Berni Rossella , Scarano Valeria Leonarda , Bertocci Francesco , Catelani Marcantonio
Published: April 2013

This paper deals with an analysis of random effects for microelectronic data. More precisely, by considering the technical challenges related to the use of electrically conductive adhesives such as soldering material in electronics, the sources of variabilities related to different electrically conductive adhesive characteristics and working process variables are evaluated. Random effects are involved in a response surface methodology setting, and the results are compared with a Bayesian approach where variance components are estimated through a log‐posterior expressed as the product of the information matrix and restricted maximum likelihood estimates of variance components. Copyright © 2013 John Wiley & Sons, Ltd.
Coexpression of luxA and luxB genes of Vibrio fischeri in NIH3T3 mammalian cells and evaluation of its bioluminescence activities
Authors: Tehrani Golnaz Asaadi , Mirzaahmadi Sina , Bandehpour Mojgan , Kazemi Bahram
Published: April 2013

Expression of bacterial luciferase enzyme (lux) in eukaryotic cells would provide a new bioreporter system for in vivo imaging and diagnostics technology. In spite of this, until now only a few efforts have been made to express bacterial luciferase enzyme in eukaryotic cells. We attempted to synthesize an expression construct of luxA and luxB genes from Vibrio fischeri. The luxA and luxB genes were cloned into the MCS of pTZ57R via the 5' kpnI, BamHI and BamHI, EcoRI restriction sites to generate pTZ57R/luxA and pTZ57R/luxB respectively, then newly synthesized constructs were cleaved with the same enzymes and respectively cloned into the pcDNA3.1+(Hyg) and pcDNA3.1+(Neo) expression vectors to create pcDNA3.1+(Hyg)/luxA and pcDNA3.1+(neo)/luxB. Recombinant constructs were cotransfected to the NIH3T3 cell line. Gene expression was confirmed by reverse transcription–polymerase chain reaction, sodium dodecyl sulfate–polyacrylamide gel electrophoresis and Western blotting; in addition, bioluminescence characteristics of transfected NIH3T3 cell lines were evaluated by decanal supplement. In conclusion, in the current research, separate vector systems were constructed, which are composed of bacterial luciferase genes (luxA and luxB) that accordingly have not already been reported. These results hold promise toward the potential development of an autonomous light‐generating lux reporter system in eukaryotic cells. Copyright © 2013 John Wiley & Sons, Ltd.
Microfluidic culture models to study the hydrodynamics of tumor progression and therapeutic response
Authors: Buchanan Cara , Rylander Marissa Nichole
Published: April 2013

The integration of tissue engineering strategies with microfluidic technologies has enabled the design of in vitro microfluidic culture models that better adapt to morphological changes in tissue structure and function over time. These biomimetic microfluidic scaffolds accurately mimic native 3D microenvironments, as well as permit precise and simultaneous control of chemical gradients, hydrodynamic stresses, and cellular niches within the system. The recent application of microfluidic in vitro culture models to cancer research offers enormous potential to aid in the development of improved therapeutic strategies by supporting the investigation of tumor angiogenesis and metastasis under physiologically relevant flow conditions. The intrinsic material properties and fluid mechanics of microfluidic culture models enable high‐throughput anti‐cancer drug screening, permit well‐defined and controllable input parameters to monitor tumor cell response to various hydrodynamic conditions or treatment modalities, as well as provide a platform for elucidating fundamental mechanisms of tumor physiology. This review highlights recent developments and future applications of microfluidic culture models to study tumor progression and therapeutic targeting under conditions of hydrodynamic stress relevant to the complex tumor microenvironment. Biotechnol. Biotechnol. Bioeng. 2013; 110: 2063–2072. © 2013 Wiley Periodicals, Inc.
Validated UPLC‐MS/MS method for determination of moclobemide in human brain cell supernatant and its application to bidirectional transport study
Authors: Li‐Bo Dai , Miao Yan , Huan‐De Li , Ping‐Fei Fang , Feng Wang , Yang Deng
Published: April 2013

A simple and sensitive analytical method based on ultraperformance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS) has been developed for determination of moclobemide in human brain cell monolayer as an in vitro model of blood–brain barrier. Brucine was employed as the internal standard. Moclobemide and internal standard were extracted from cell supernatant by ethyl acetate after alkalinizing with sodium hydroxide. The UPLC separation was performed on an Acquity UPLCTM BEH C18 column (50 × 2.1 mm, 1.7 µm, Waters, USA) with a mobile phase consisting of methanol–water (29.5:70.5, v/v); the water in the mobile phase contained 0.05% ammonium acetate and 0.1% formic acid. Detection of the analytes was achieved using positive ion electrospray via multiple reaction monitoring mode. The mass transitions were m/z 269.16 → 182.01 for moclobemide and m/z 395.24 → 324.15 for brucine. The extraction recovery was 83.0–83.4% and the lower limit of quantitation (LLOQ) was 1.0 ng/mL for moclobemide. The method was validated from LLOQ to 1980 ng/mL with a coefficient of determination greater than 0.999. Intra‐ and inter‐day accuracies of the method at three concentrations ranged from 89.1 to 100.9% for moclobemide with precision of 1.1–9.6%. This validated method was successfully applied to bidirectional transport study of moclobemide blood–brain barrier permeability. Copyright © 2013 John Wiley & Sons, Ltd.