bluuebunny/crossref_metadata_2025 huggingface dataset:
Food allergy knowledge of parents – is ignorance bliss?
Authors: Goossens Nicole J. , Flokstra‐de Blok Bertine M. J. , van der Meulen Gerbrich N. , Botjes Erna , Burgerhof Hans G. M. , Gupta Ruchi S. , Springston Elizabeth E. , Smith Bridget , Duiverman Eric J. , Dubois Anthony E. J.
Published: June 2013

Background

Food allergic children are at least partially dependent on their parents to care for their food allergy. In addition, parents are often responsible for the education of others regarding food allergy, including the family, school, neighbors, and friends. The aim of this study was to investigate food allergy knowledge, attitudes, and beliefs of parents with food allergic children in the Netherlands. In addition, a cross‐cultural comparison was made between parents from the USA and parents from the Netherlands.

Methods

The original Chicago Food Allergy Research Survey for Parents of Children with Food Allergy (CFARS‐PRNT) was translated into Dutch. Parents of children with at least one doctor‐diagnosed food allergy were included. Knowledge scores and attitude/beliefs scores were determined and compared with the data from 2945 parents from the USA. Predictors of overall knowledge scores were investigated.

Results

Dutch parents of children completed the translated CFARS‐PRNT (n = 299). The mean overall knowledge score in the Netherlands was 9.9 after adjusting for guessing, compared with 12.7 in the USA (p < 0.001). Attitudes and beliefs regarding food allergy among parents from the Netherlands were generally more optimistic. The overall knowledge scores could be predicted by country of origin, educational degree, being member of a patient organization, visiting an allergist, and a history of anaphylaxis.

Conclusions

Food allergy knowledge among parents of food allergic children from the Netherlands is suboptimal when compared with their counterparts from the USA, although these parents tend to be more optimistic toward food allergy than parents from the USA.
Analysis of carotenogenic gene expression in petals and leaves of carnation (Dianthus caryophyllus L.)
Authors: Ohmiya Akemi , Tanase Koji , Hirashima Masumi , Yamamizo Chihiro , Yagi Masafumi
Published: June 2013

Carnation (Dianthus caryophyllus L.) belongs to the family Caryophyllaceae in the order Caryophyllales. Plants in this order do not accumulate carotenoids in petals. To understand how carotenoid accumulation is controlled in carnation petals, we analysed the expression of genes related to carotenoid accumulation. Petals at an early stage of development accumulated small amounts of carotenoids. As petals matured, their carotenoid content decreased to extremely low levels. In contrast, carnation leaves contained substantial amounts of carotenoids that are essential for photosynthesis. Most of the carotenogenic genes were expressed in petals at levels similar to those in leaves, and the expression levels of these genes increased during petal development. Genes encoding phytoene synthase and lycopene ε‐cyclase were exceptions. Their expression levels in petals were very low compared with those in leaves. Expression of the gene encoding carotenoid cleavage dioxygenase 4 was detected in neither leaves nor petals. These data suggest that the low levels of carotenoids in carnation petals are caused not by enzymatic degradation but rather by low rates of carotenoid biosynthesis.
Impact of Dye‐Protein Interaction and Silver Nanoparticles on Rose Bengal Photophysical Behavior and Protein Photocrosslinking
Authors: Simpson Madeline J. , Poblete Horacio , Griffith May , Alarcon Emilio I. , Scaiano Juan C.
Published: June 2013

The role of recombinant Type‐I human collagen in the free form or forming AgNP@collagen on the photophysical and photochemical behavior of rose Bengal was analyzed. The formation of dye aggregates on the protein surface was experimentally observed and corroborated by docking calculations. The formation of such aggregates is believed to change the main oxidative mechanism from Type‐II (singlet oxygen) to Type‐I (free radical) photosensitization. Remarkably, the presence of AgNP in the form of AgNP@collagen altered the dynamics of dye triplet deactivation, effectively preventing the dye degradation and reducing the extent of protein crosslinked. Both crosslinked rHC and AgNP@collagen were able to support fibroblasts proliferation, but only the material containing silver was resistant to S. epidermidis infection.
Improved In vitro and In vivo Cutaneous Delivery of Protoporphyrin IX from PLGA‐based Nanoparticles
Authors: da Silva Carolina L. , Del Ciampo José O. , Rossetti Fábia C. , Bentley Maria V. L. B. , Pierre Maria B. R.
Published: June 2013

We report the development of d, l lactic co‐glycolic acid) (PLGA)‐based nanoparticles (NPs) for topical delivery of protoporphyrin IX (PpIX), a photosensitizer (PS), in treatments like photodynamic therapy (PDT) of skin cancers. PpIX‐NPs were obtained in ~75.0% yield, encapsulation efficiency of 67.7%, drug content of 50.3 μg mg−1, average diameter of 290 nm maintained up to 30 days and a zeta potential of 32.3 mV. Sustained in vitro release of PpIX through artificial membranes following Higuchi kinetics was kept up to 10 days. In vitro retentions of PpIX both in stratum corneum (SC) and epidermis + dermis ([EP + D]) were higher from NPs (23.0 and 10.0 times, respectively) compared to control solutions at all times. Quantification of PpIX by extraction, after in vivo skin application of NPs‐PpIX on hairless mice, showed higher retention of the PS both in SC and in [EP + D] (3.0 and 2.0 times, respectively) compared to control solutions. Taken together, the results indicate that NPs are suitable for PpIX encapsulation showing minimal permeation through the skin and a localized effect, characteristics of a potential and promising delivery system for PDT‐associated treatments of skin cancers, photodiagnosis and their off‐label uses.
Immunity, resistance and tolerance in bird–parasite interactions
Authors: Sorci G.
Published: June 2013

Interacting pathogens and hosts have evolved reciprocal adaptations whose function is to allow host exploitation (from the pathogen stand point) or minimize the cost of infection (from the host stand point). Once infected, two strategies are offered to the host: parasite clearing (resistance) and withstanding the infection while paying a low fitness cost (tolerance). In both cases, the immune system plays a central role. Interestingly, whatever the defence strategy adopted by the host, this is likely to have an effect on parasite evolution. Given their short generation time and large population size, parasites are expected to rapidly adapt to the environmental conditions provided by their hosts. The immune system can therefore represent a powerful engine of parasite evolution, with the direction of such evolutionary trajectory depending on, among other factors, (i) the type of mechanism involved (resistance or tolerance) and (ii) the damage induced by overreacting immune defences. In this article, I will discuss these different issues focusing on selected examples of recent work conducted on two bird pathogens, the protozoa responsible for avian malaria (Plasmodium sp.) and the bacterium Mycoplasma gallisepticum.
Competitive Quality Choice and Remanufacturing
Authors: Örsdemir Adem , Kemahlıoğlu‐Ziya Eda , Parlaktürk Ali K.
Published: June 2013

We consider an original equipment manufacturer (OEM) who faces competition from an independent remanufacturer (IR). The OEM decides the quality of the new product, which also determines the quality of the competing remanufactured product. The OEM and the IR then competitively determine their production quantities. We explicitly characterize how the OEM competes with the IR in equilibrium. Specifically, we show that the OEM relies more on quality as a strategic lever when it has a stronger competitive position (determined by the relative cost and value of new and remanufactured products), and in contrast it relies more heavily on limiting quantity of cores when it has a weaker competitive position. The IR's entry threat as well as its successful entry can decrease the consumer surplus. Furthermore, our results illustrate that ignoring the competition or the OEM's quality choice leads to overestimating benefits of remanufacturing for consumer and social welfare. In addition, we show an IR with either a sufficiently weak competitive position (so the OEM deters entry) or a sufficiently strong one (so the OEM is forced to limit quantity of cores) is desirable for reducing the environmental impact. Comparing our results with the benchmark in which the OEM remanufactures suggests that encouraging IRs to remanufacture in lieu of the OEMs may not benefit the environment. Furthermore, the benchmark illustrates that making remanufacturing more attractive improves the environmental impact when the remanufacturer is the OEM, while worsening it when remanufacturing is done by the IR.
Spectral Estimation of Covolatility from Noisy Observations Using Local Weights
Authors: Bibinger Markus , Reiß Markus
Published: June 2013

We propose localized spectral estimators for the quadratic covariation and the spot covolatility of diffusion processes, which are observed discretely with additive observation noise. The appropriate estimation for time‐varying volatilities is based on an asymptotic equivalence of the underlying statistical model to a white‐noise model with correlation and volatility processes being constant over small time intervals. The asymptotic equivalence of the continuous‐time and discrete‐time experiments is proved by a construction with linear interpolation in one direction and local means for the other. The new estimator outperforms earlier non‐parametric methods in the literature for the considered model. We investigate its finite sample size characteristics in simulations and draw a comparison between various proposed methods.
Dyadic Analyses of Preschool‐aged Children's Friendships: Convergence and Differences between Friendship Classifications from Peer Sociometric Data and Teacher's Reports
Authors: Shin Nana , Kim Mina , Goetz Stephanie , Vaughn Brian E.
Published: June 2013

Peer sociometrics and teachers' friendship reports were compared in 2179 preschool dyads. One hundred twenty of 306 reciprocated friend dyads from peer sociometric data were also identified as good friends by their classroom teachers, and 301 of 600 of non‐reciprocated dyads in peer data were named as friends by one or both classroom teachers (overall kappa = .16). Friendship classifications from both peer and teacher data had significant relations with variables relevant to peer interactions, social skills, peer acceptance, and teacher‐rated scales (six of seven tests significant for peer data; five of eight significant for teacher data). Multilevel analyses indicated that friendship status effects were not qualified by classroom‐level differences. Findings suggest that sociometric tasks can identify preschoolers' peer friendships and that the range of correlates may be broader in peer‐choice data than in teachers' friendship evaluations.
Functional variants of ERAP1 gene are associated with HLA‐B27 positive spondyloarthritis
Authors: Cherciu M. , Popa L. O. , Bojinca M. , Dutescu M. I. , Bojinca V. , Bara C. , Popa O. M.
Published: June 2013

We investigated two nonsynonymous variants (rs30187 and rs27044) of ERAP1 gene in HLA‐B27 positive individuals (150 spondyloarthritis and 108 controls) and in general ankylosing spondylitis (AS) patients (n = 137) vs random controls (n = 139). Both single nucleotide polymorphisms (SNPs) were associated with the risk of spondyloarthritis [odds ratio (OR) 1.80, 95% confidence interval (CI) 1.24–2.62, P = 0.001 for rs30187, OR 1.58, 95% CI 1.07–2.34, P = 0.02 for rs27044]. The CC haplotype was a protective factor (P = 0.002), while the TG haplotype was a risk factor (P = 0.01) for spondyloarthritis. The SNP rs30187 was also associated with the risk of HLA‐B27+ AS. For the general group of AS, the carriers of minor alleles showed an increased risk for the disease (OR 1.92, 95% CI 1.17–3.13 for rs30187, OR 1.74, 95% CI 1.08–2.80 for rs27044). This is the first study that shows the association of ERAP1 gene variants and haplotypes with HLA‐B27 positive spondyloarthritis.
The role of FaBG3 in fruit ripening and B. cinerea fungal infection of strawberry
Authors: Li Qian , Ji Kai , Sun Yufei , Luo Hao , Wang Hongqing , Leng Ping
Published: June 2013

In plants, β–glucosidases (BG) have been implicated in developmental and pathogen defense, and are thought to take part in abscisic acid (ABA) synthesis via hydrolysis of ABA glucose ester to release active ABA; however, there is no genetic evidence for the role of BG genes in ripening and biotic/abiotic stress in fruits. To clarify the role of BG genes in fruit, eight Fa/FvBG genes encoding β–glucosidase were isolated using information from the GenBank strawberry nucleotide database. Of the Fa/FvBG genes examined, expression of FaBG3 was the highest, showing peaks at the mature stage, coincident with the changes observed in ABA content. To verify the role of this gene, we suppressed the expression of FaBG3 via inoculation with Agrobacterium tumefaciens containing tobacco rattle virus carrying a FaBG3 fragment (RNAi). The expression of FaBG3 in FaBG3‐RNAi‐treated fruit was markedly reduced, and the ABA content was lower than that of the control. FaBG3‐RNAi‐treated fruit did not exhibit full ripening, and were firmer, had lower sugar content, and were pale compared with the control due to down‐regulation of ripening‐related genes. FaBG3‐RNAi‐treated fruit with reduced ABA levels were much more resistant to Botrytis cinerea fungus but were more sensitive to dehydration stress than control fruit. These results indicate that FaBG3 may play key roles in fruit ripening, dehydration stress and B. cinerea fungal infection in strawberries via modulation of ABA homeostasis and transcriptional regulation of ripening‐related genes.
EMU and Trade Revisited: Long‐Run Evidence Using Gravity Equations
Authors: Camarero Mariam , Gómez Estrella , Tamarit Cecilio
Published: June 2013

In this paper, we present evidence of the long‐run effect of the euro on trade for the twelve initial EMU countries for the period 1967–2008 from a double perspective. First, we pool all the bilateral combinations of trade flows among the EMU countries in a panel cointegration gravity specification. Second, we estimate a gravity equation for each of the EMU members vis‐à‐vis the other eleven partners. We apply panel cointegration techniques based on factor models that account for cross‐dependence and structural breaks. Whereas the joint gravity equation provides evidence on the aggregate effect of the euro on intra‐European trade, by isolating the individual countries, we assess which of the member countries have obtained a larger benefit from the euro. The results show that the euro has had a positive though small effect on trade. Belgium and Luxembourg, France and Italy are the countries more benefited from the introduction of the euro. The effects for exports to third countries are in general more moderate, and, with the exception of Greece, there is no evidence of diversion effects.
Blade Loading Effects on Axial Turbine Tip Leakage Vortex Dynamics
and Loss
Authors: Huang Arthur C. , Greitzer Edward M. , Tan Choon S. , Clemens Eugene F. , Gegg Steven G. , Turner Edward R.
Published: June 2013

Numerical simulations have been carried out to define the loss generation mechanisms associated with tip leakage in unshrouded axial turbines. Tip clearance vortex dynamics are a dominant feature of two mechanisms important in determining this loss: (i) decreased swirl velocity due to vortex line contraction in regions of decreasing axial velocity, i.e., adverse pressure gradient, and (ii) vortex breakdown and reverse flow in the vortex core. The mixing losses behave differently from the conventional view of flow exiting a turbine tip clearance. More specifically, it is shown through control volume arguments and computations that as a swirling leakage flow passes through a pressure rise, such as in the aft portion of the suction side of a turbine blade, the mixed-out loss can either decrease or increase. For turbines, the latter typically occurs if the deceleration is large enough to initiate vortex breakdown, and it is demonstrated that this can occur in modern turbines. The effect of blade pressure distribution on clearance losses is illustrated through computational examination of turbine blades with forward loading at the tip and with aft loading. A 15% difference in leakage loss is found between the two due to lower clearance vortex deceleration (lower core static pressure rise) with forward loading and, hence, lower vortex breakdown loss. Additional computational experiments, carried out to define the effects of blade loading, incidence, and solidity, are found to be consistent with the proposed ideas linking blade pressure distribution, vortex breakdown, and turbine tip leakage loss.
Identifying the Interaction Between Influenza and Pneumococcal Pneumonia Using Incidence Data
Authors: Shrestha Sourya , Foxman Betsy , Weinberger Daniel M. , Steiner Claudia , Viboud Cécile , Rohani Pejman
Published: June 2013

Influenza virus increases susceptibility to pneumococcal pneumonia in individuals but has only a modest impact on the total population.
Restoring the Hormone-Making Machinery
Authors: Balcells Mercedes
Published: June 2013

A single differentiation strategy for embryonic and adult stem cells produces pancreatic β–like cells that control glucose levels in diabetic mice.
Of Mice and Men
Authors: Narla Goutham
Published: June 2013

Co-clinical trials of human and mouse prostate cancer reveal targets of castrate resistant prostate cancer.
Candida albicans CUG Mistranslation Is a Mechanism To Create Cell Surface Variation
Authors: Miranda Isabel , Silva-Dias Ana , Rocha Rita , Teixeira-Santos Rita , Coelho Carolina , Gonçalves Teresa , Santos Manuel A. S. , Pina-Vaz Cidália , Solis Norma V. , Filler Scott G. , Rodrigues Acácio G.
Published: June 2013

In the human fungal pathogen
Candida albicans
, the CUG codon is translated 97% of the time as serine and 3% of the time as leucine, which potentially originates an array of proteins resulting from the translation of a single gene. Genes encoding cell surface proteins are enriched in CUG codons; thus, CUG mistranslation may influence the interactions of the organism with the host. To investigate this, we compared a
C. albicans
strain that misincorporates 28% of leucine at CUGs with a wild-type parental strain. The first strain displayed increased adherence to inert and host molecules. In addition, it was less susceptible to phagocytosis by murine macrophages, probably due to reduced exposure of cell surface β-glucans. To prove that these phenotypes occurred due to serine/leucine exchange, the
C. albicans
adhesin and invasin
ALS3
was expressed in
Saccharomyces cerevisiae
in its two natural isoforms (Als3p-Leu and Als3p-Ser). The cells with heterologous expression of Als3p-Leu showed increased adherence to host substrates and flocculation. We propose that CUG mistranslation has been maintained during the evolution of
C. albicans
due to its potential to generate cell surface variability, which significantly alters fungus-host interactions.

IMPORTANCE
The translation of genetic information into proteins is a highly accurate cellular process. In the human fungal pathogen
Candida albicans
, a unique mistranslation event involving the CUG codon occurs. The CUG codon is mainly translated as serine but can also be translated as leucine. Leucine and serine are two biochemically distinct amino acids, hydrophobic and hydrophilic, respectively. The increased rate of leucine incorporation at CUG decoding triggers
C. albicans
virulence attributes, such as morphogenesis, phenotypic switching, and adhesion. Here, we show that CUG mistranslation masks the fungal cell wall molecule β-glucan that is normally recognized by the host immune system, delaying its response. Furthermore, we demonstrate that two different proteins of the adhesin Als3 generated by CUG mistranslation confer increased hydrophobicity and adhesion ability on yeast cells. Thus, CUG mistranslation functions as a mechanism to create protein diversity with differential activities, constituting an advantage for a mainly asexual microorganism. This could explain its preservation during evolution.
A qualitative study on the perceptions of preventing falls as a health priority among older people in Northern India
Authors: Jagnoor Jagnoor , Keay Lisa , Jaswal Nidhi , Kaur Manmeet , Ivers Rebecca
Published: June 2013

Background

In India, fall-related injury morbidity and mortality is an emerging public health problem in older people. Despite awareness of a growing burden, there is a scarcity of literature on effective and acceptable interventions. This study was undertaken to explore the perceptions of older people regarding the risk of falls and understanding of fall prevention programmes.

Methods

We conducted six focus group discussions (FGDs), comprising single gender for three socio-demographic groups in a north Indian city, Chandigarh, in 2011. FGDs were conducted in local language (Punjabi), recorded, transcribed and translated in English. Two researchers independently conducted thematic analysis.

Results

Focus group participants were aware of the devastating consequences of fall-related injuries. The predominant reasons for explaining an increased risk of falling was age, uneven surfaces, physical weakness and mental health. There were several other competing health priorities in this population. Preventive measures ranging from individual to government level initiatives were suggested. The experience, knowledge, perceptions and health priorities were diverse among the three socio-demographic groups. However, the feasibility, acceptability and effectiveness for improving balance and strength using yoga in this population needs to be evaluated.

Conclusions

Careful consideration of health priorities is required for development of falls prevention, particularly among the urban poor. Further, initiatives that foster community engagement, such as participatory action may increase acceptability of initiatives to prevent fall-related injury among older people in India.
Verification of serum reference intervals for free light chains in a local South African population
Authors: Zemlin Annalise E , Rensburg Megan A , Ipp Hayley , Germishuys Jurie J , Erasmus Rajiv T
Published: June 2013

Monoclonal serum free light chain measurements are used to follow up and manage patients with monoclonal gammopathies, and abnormal serum free light chain ratios are associated with risk of progression in certain diseases. We aimed to validate the reference intervals in our population. Reference intervals for κ and λ free light chains were established on 120 healthy adults. Creatinine levels were measured to exclude renal dysfunction and serum protein electrophoresis was performed. All creatinine values were within normal limits. After exclusion of subjects with abnormal serum protein electrophoreses, 113 subjects were available for analysis. The 95% reference interval was 6.3–20.6 mg/L for κ free light chains, 8.7–25.9 mg/L for λ free light chains and 0.46–1.23 for free light chain ratio. Most of the values fell within the manufacturer's recommended limits and therefore could be used for our population.
HYBRID OF GENETIC ALGORITHM AND SIMULATED ANNEALING FOR SUPPORT VECTOR REGRESSION OPTIMIZATION IN RAINFALL FORECASTING
Authors: ZHU CHANGMING , WU JIANSHENG
Published: June 2013

Accurate forecasting of rainfall has been one of the most important issues in hydrological research such as river training works and design of flood warning systems. Support vector regression (SVR) is a popular regression method in rainfall forecasting. Type of kernel function and kernel parameter setting in the SVR traing procedure, along with the input feature subset selection, significantly influence regression accuracy. In this paper, an effective hybrid optimization strategy by combining the strengths of genetic algorithm (GA) and simulated annealing (SA), is employed to simultaneously optimize the input feature subset selection, the type of kernel function and the kernel parameter setting of SVR, namely GASA–SVR. The developed GASA–SVR model is being applied for monthly rainfall forecasting in Guilin of Guangxi. The GA is carried out as a main frame of this hybrid algorithm while SA is used as a local search strategy to help GA jump out of local optima and avoid sinking into the local optimal solution early. Compared with SVR, pure GA–SVR and HGA–SVR, results show that the hybrid GASA–SVR model can correctly select the discriminating input features subset, successfully identify the optimal type of kernel function and all the optimal values of the parameters of SVR with the lowest prediction error values in rainfall forecasting, can also significantly improve the rainfall forecasting accuracy. Experimental results reveal that the predictions using the proposed approach are consistently better than those obtained using the other methods presented in this study in terms of the same measurements. Those results show that the proposed GASA–SVR model provides a promising alternative to monthly rainfall prediction.
Thick-skin orogen–foreland interactions and their controlling factors, Northern Andes of Colombia
Authors: Hermeston S. , Nemčok M.
Published: June 2013

The study draws from reflection seismic,
in-situ
stress and low-temperature geochronology data on the Eastern Cordillera–Llanos foreland basin system of Colombia, which is an example of the retro-wedge of the orogen with an advancing subduction zone. The system was obliquely converging during deposition of the Lower Oligocene–Lower Miocene Carbonera to recent Guayabo formations, recording it by the northeastward depocentre shift in the proximal Llanos Basin. While the southern portion of the foreland did not flex and undergo flexural normal faulting after Carbonera deposition, the northern portion did. The earthquake data indicate that the northern Eastern Cordillera undergoes strengthening by internal deformation, while the southern segment is already strong enough to undergo significant displacements dominantly along its bounding fault systems. Furthermore, the southern segment initiated detachment of the first thick-skin blocks from the proximal Llanos Basin. Such co-existence of different convergence maturity stages along the orogen strike allows unravelling of its development starting with internal deformation and foreland flexure, followed by mountain building and large-scale boundary fault displacements, to the large-scale foreland deformation. The onset of new foreland accretion seems to be controlled by the resistance of the foreland plate to flexing, given that the orogenic engine continues to drive convergence.

Supplementary material:

Discussion of evidences for dextral transpression in the Eastern Cordillera, data on exhumation history of the Eastern Cordillera and colour versions of Figures 4–6 are available at
http://www.geolsoc.org.uk/SUP18629
Interaction between thin- and thick-skinned tectonics in the foothill areas of an inverted graben. The Middle Magdalena Foothill belt
Authors: Moreno Néstor , Silva Alejandro , Mora Andrés , Tesón Eliseo , Quintero Isaid , Rojas Luis Ernesto , Lopez Cristina , Blanco Vladimir , Castellanos Jaime , Sanchez Javier , Osorio Lidy , Namson Jay , Stockli Daniel , Casallas Wilson
Published: June 2013

The Magdalena Valley fold-and-thrust belt is a tectonic province associated with inverted rift zones. This belt displays a narrow and discontinuous deformation front indicating association with inversion tectonics. We show the differences with an analogue belt on the eastern side of the Eastern Cordillera (Llanos foothills). To do that we use structural data (seismic, wells and geological maps) which characterize different structural geometries as well as palaeocurrents, provenance and thermochronology to analyse the timing of deformation. The new datasets allowed us to detect that inversion is limited whenever the stresses are more orthogonal to the rift structures, whereas the mountain front is more segmented in comparison to the Eastern Foothills because of the absence of a continuous low basal friction detachment horizon and a pronounced eastwards basement dip. These two factors favoured fault hard linkage. It is remarkable that, in spite of the distinct segmentation, all the different segments in the Magdalena belt are coeval.

Supplementary material:

U–Pb Zircon data are available at:
http://www.geolsoc.org.uk/SUP18630
.
Mass Spectrometric Studies of Oxides
Authors: Jacobson Nathan S.
Published: June 2013

Current studies at NASA Glenn on oxide thermodynamics are discussed. Previous studies on the vaporization of B2O3 in reducing atmospheres led to inconsistent studies when B was used as a reductant. It is shown that liquid B2O3 does not wet B and a clear phase separation was noted in the Knudsen cell. This problem was solved by using FeB and Fe2B to supply a different and constant activity of B. The thermodynamic data thus derived are compared to quantum chemical composite calculations. A major problem in high temperature mass spectrometry is the determination of accurate ionization cross sections, particularly for molecules. The method of Deutsch and Mark shows promise and some sample calculations are discussed. Finally current studies on the thermodynamics of rare earth silicates are discussed. Here the problems are obtaining a measurable signal from SiO2 vaporization and non-equilibrium vaporization. The use of a Ta reducing agent provides a stronger signal, which is related to silica activity. The Whitman-Motzfeld relation adapted to KEMS measurements is applied to obtain equilibrium pressures.
Vaporization Processes and Thermodynamic Properties of Oxide Systems Studied by High Temperature Mass Spectrometry
Authors: Stolyarova V. L.
Published: June 2013

Information on the vaporization processes and thermodynamic properties of the ternary silicate systems Na2O-B2O3-SiO2, Cs2O-B2O3-SiO2, Rb2O-B2O3-SiO2, MgO-B2O3-SiO2, CaO-B2O3-SiO2, SrO-B2O3-SiO2, BaO-B2O3-SiO2, MgO-Al2O3-SiO2, CaO-Al2O3-SiO2, CaO-TiO2-SiO2, BaO-TiO2-SiO2, PbO-B2O3-SiO2 and ZnO-B2O3-SiO2 together with previously obtained data is discussed. Various types of vapour species were found over the oxide systems studied such as the associated, dissociated and polymerized products of vaporization. The systematic trends in the vaporization of binary and multicomponent oxide systems are illustrated and discussed from the point of view of the acid-base concept. Results on determination of thermodynamic functions in oxide systems were considered taking into account the main requirements for the confirmation of their reliability. The general lattice theory of associated solutions was used for the calculation of thermodynamic properties of the ternary silicate melts studied. Some industrial applications of multicomponent oxide systems are also illustrated.
Vapor Phase of Thermally Unstable Sm, Eu, Yb Bromides
Authors: Sergeev D. N. , Butman Mikhail F. , Motalov V. B. , Kudin L. S. , Krämer K. W.
Published: June 2013

Vaporization of thermally unstable SmBr3, YbBr3, SmBr2, EuBr2, and YbBr2 is investigated by the high temperature mass spectrometry. It is found that the composition of vapor phase changes in the course of vaporization due to thermal decomposition of tribromides and disproportionation of dibromides. The neutral (Ln, Br, Br2, LnBr, LnBr2, LnBr3, Ln2Br4, Ln2Br5, and Ln2Br6) and charged (Br–, LnBr3
–, LnBr4
–) species are present in vapor at various vaporization stages. Eventually for each sample studied the vaporization approaches steadiness when the LnBr2 molecules are predominant in the vapor.
Vaporizers for KEMS: Measurement Errors Depending on Their Design
Authors: Shilov A. L.
Published: June 2013

Three types of resistance heating vacuum furnaces for KEMS are considered. It is shown that the measured vapor species from the inner volume of the furnace resulting from dispersion of the molecular beam may introduce significant systematic error and restrict application of the direct comparison of ion currents method. The required corrections are assessed using the results of vaporization trials with Ag, Cu, CsCl.
A Fairly Common Error in Processing the Results of Knudsen Effusion Mass Spectrometry: Sublimation Enthalpy of Vanadium as an Example
Authors: Gusarov A. V.
Published: June 2013

It has been shown in this paper, that a fairly common approach of Knudsen effusion mass spectrometry based on the so called “self-calibration” for the instrument sensitivity (combination of single measurement for absolute vapor pressure by Knudsen method with the mass spectrometry for its temperature dependence) leads to a very large uncertainty for the enthalpy of sublimation for the substance under investigation. The uncertainty may not be less than the uncertainty of initial single measurement for vapor pressure, and so, the array of data obtained by its combination with the mass spectral data is not the array of independent measurements. The difference between the uncertainties for two approaches (considered and criticized) may be near one order of magnitude for vapor pressure. There are presented the results of 13 measurements of vapor pressure for vanadium in the paper (1). Formal statistical treating of these results leads to sublimation enthalpy with the uncertainty less than ±1 kJ·mol-1, although the uncertainty of the calibration experiments (2 experiments) amounts near ±13 kJ·mol-1.
Thermodynamic Properties of Al-Cr-Fe Alloys: Experimental Investigation by Knudsen Effusion Mass Spectrometry
Authors: Markus Torsten , Motalov V. B. , Kath D. , Singheiser Lorenz
Published: June 2013

Vaporization of ternary Al-Cr-Fe and binary Al-Fe, and Cr-Fe alloys has been investigated in the temperature range 1234-1608 K by Knudsen effusion mass spectrometry (KEMS). The atoms Al, Cr, and Fe were found to be the only vapor species. Partial pressures of the elements were evaluated from the measured ion intensities and thermodynamic activities of the alloy components were determined by pressure ratio method (p/p°). Reliable partial and integral molar enthalpies, entropies and Gibbs energies for all the components have been obtained for the systems under investigation. The partial molar enthalpies and entropies were found to be nearly temperature independent over the wide temperature range investigated.
Experimental Thermodynamics of New Electrode Materials for Li-Ion Batteries
Authors: Henriques D. , Motalov V. B. , Bencze L. , Markus Torsten
Published: June 2013

Vaporization of five liquid binary Li-Sn alloys (molar fractions x
Li = 0.1; 0.2; 0.3; 0.4; and 0.5) as well as pure Li have been investigated in the temperature range 576-1040 K by Knudsen effusion mass spectrometry (KEMS). The Thermodynamic activity of lithium was determined by the ratio of ion current intensities measured over the alloy and the pure metal. The activity of tin was determined by Gibbs-Duhem integration. The results were approximated by Redlich-Kister sub-regular solution model and compared with the available literature data.
Thermodynamic Measurement of Phosphates by Double Knudsen Cell Mass Spectrometry
Authors: Nagai T. , Maeda M.
Published: June 2013

Double Knudsen cell mass spectrometry was adapted for thermodynamic measurement of phosphates to obtain the accurate thermodynamic information. The ion currents of gaseous phosphorus and phosphorus oxides in equilibrium with a mixture of AlPO4 and Al2O3 at 1473 – 1573 K were measured by double Knudsen cell mass spectrometry. The Gibbs energy change of formation of AlPO4 was estimated by using these ion currents.
Current Global Fuel Cell R&D and Future Research Needs
Authors: Behling Noriko
Published: June 2013

Abstract—Fuel cell research and business sectors must overcome fundamental barriers before they can field products that compete on their own in the energy and vehicle markets. Investment trends, R&D programs, and commercialization activities of 180 companies and 50 major government R&D programs worldwide indicate that total private sector and government investment in fuel cell technology and product development has amounted to US$22 billion over the past 18 years, funding a wide range of stationary and vehicle applications. Nonetheless, this investment has not led to commercially viable products. This article, based on my recently published book—Fuel Cells: Current Technology Challenges and Future Research Needs—provides the rationale for this ambitious research (1). We propose launching a National Fuel Cell Development Project (NFCDP)—a 5-year, $2-billion-a-year basic research effort—that would focus solely on obtaining detailed knowledge of fuel cell electrochemical operations and thereby lay the foundation for achieving major breakthroughs in fuel cell technology necessary for commercialization.
Direct Fuel Cell DFC Durability Progress
Authors: Farooque Mohammad , Hilmi A. , Venkataraman Ramki , Yuh Chao-Yi
Published: June 2013

FuelCell Energy, Inc. (FCE) is a global leader in providing ultra-clean baseload distributed generation at more than 50 locations worldwide. These plants have generated more than one billion kilowatt hours of ultra-clean power using a variety of fuels including renewable biogas, coal-bed methane, propane, and natural gas. The generator design is based on the internal reforming direct carbonate fuel cell (DFC®) concept. The key to widespread fuel cell commercial acceptance is grid competitive cost of electricity (COE). The prime contributor to the fuel cell COE is first-time and most importantly, periodic replacement costs of the fuel cell stack. As such, the focus of technology development is on reducing fuel cell cost as well as extending service. This paper reports on the progress on understanding and extending the carbonate fuel cell durability.
Optimization of the Working Conditions of a Laboratory Size (100 cm2) Molten Carbonate Fuel Cell
Authors: Milewski Jaroslaw , Wołowicz Marcin , Lewandowski Janusz
Published: June 2013

A mathematical model of a Molten Carbonate Fuel Cell (MCFC) is used to simulate an experimental lab-stand single fuel cell unit with a size of 100 cm2. The comparison of simulated data against the experimental results is shown and commented. The model was used for optimizing the working parameters of the cell. The results of the optimizing procedures were validated during experiments.
SOFC Technology Development for Distributed and Centralized Power Generation
Authors: Ghezel-Ayagh Hossein , Jolly Stephen , Patel Dilip , Nagar Jacob , Davis Keith E. , Willman Carl , Howard Chris , Lukas Michael , Tang Eric , Pastula Michael , Petri Randy
Published: June 2013

Integrated Gasification Fuel Cell (IGFC) power plants, incorporating solid oxide fuel cell (SOFC), are an attractive alternative to traditional pulverized coal-fired steam cycle and Integrated Gasification Combined Cycle power plants, for central power generation. Key features of the IGFC plants are: high efficiency, near-zero emissions of SOx and NOx, low water consumption, and amenability to carbon dioxide (CO2) capture. FuelCell Energy is developing SOFC systems and technology for very efficient, economically viable, coal-based power plants through a cooperative agreement with the U.S. Department of Energy. A key project objective is implementation of an innovative system concept in design of a Baseline Power Plant (>100 MW) to achieve an electrical efficiency of >55% based on coal higher heating value, exclusive of power requirements for CO2 compression. The Baseline system is designed to remove at least 90% of carbon in the syngas for sequestration as CO2. The coal-based power plant is targeted to have a cost of $700/kW (2007 US dollars) for the SOFC power block.
Research on the Relationship between SOFC Cell Performance, Adhesion Strength and Firing Temperature
Authors: Shimano Jun , Ogura Y. , Hisada K. , Katsurayama K.
Published: June 2013

SOFCs are expected to achieve high electrical conversion efficiency in the CHP systems with small generating power, but the improvement in durability performance is needed for commercialization. In order to improve durability, Toho gas is working on ways to prevent cathode from breaking away. In order to decrease abrasion, it is effective to rise the cathode’s firing temperature. However, the cell performance can decrease if the temperature is too high. This paper reports on the relationship between SOFC cell performance, adhesion strength, and calcination temperature in order to find the adequate firing temperature.
Carbon-Fuelled Solid Oxide Cells for Military Applications
Authors: Pointon Kevin David , Irvine John T.S. , Bonaccorso Alfredo Damiano
Published: June 2013

We are evaluating the suitability of solid oxide cells for efficient power generation from carbons delivered as solids to the anode space in order to satisfy the requirements of military applications such as waste-to-energy and portable power. Ample evidence in the literature testifies to the feasibility of this concept. In order to de-risk a portable battery system based on this concept, consideration is given in this paper to the anode type, gasification rate of carbons, heat and mass transfer within the cell and the control of a complete system. A palladium-based anode is preferred for operation of a cell with carbon adjacent to the anode since the electrical performance is higher and it is more resistant to oxidation under fuel starved conditions than traditional nickel anodes. There is ample experimental evidence that carbon can gasify in CO2 at sufficient rate to support operation of a battery system based on cells bearing these anodes. In fact, cell modelling suggests it is the activity of the anode that is limiting. There are significant heat and mass transfer effects within the components of the cell, but these may not prevent the achievement of sufficient electrical performance to enable a portable system. System modelling suggests such a system at the 150 W scale and equipped with enough carbon for 12 hour operation could be 48% efficient.
Field Test Results Of Residential SOFC Co-Generation System At Tokyo Gas
Authors: Ishikawa Tadaaki , Yamashita S.
Published: June 2013

Field test results of residential SOFC co-generation system at Tokyo Gas

T. Ishikawa, S. Yamashita

Product Development Dept., Tokyo Gas Lo., LTD., Tokyo, JAPAN We are developing residential SOFC co-generation system in order to commercialize it. One of our activities is to operate SOFC systems in field tests to make sure effects of installation and find technical issues. The detail is as below. A serious accident at nuclear power plants in Fukushima which was triggered by a huge earthquake on 11th March 2011 forces drastic re-formulation of Japan’s energy policy. In a series of discussions on the new energy policy, promoted use of distributed power generation is demanded more than ever as one of the main power systems, with extremely strong expectations for the fuel cell co-generation system. Tokyo Gas has been conducting research and development of solid oxide fuel cell (SOFC) which is expected to achieve the highest efficiency among all distributed power systems. In parallel with it, to verify the applicability of the SOFC for residential use and to identify technical challenges of SOFC, we have started field tests of SOFC systems of multiple manufacturers in the “Solid Oxide Fuel Cell (SOFC) demonstrative research project” with financial support from NEDO (Figure 1) [1][2]. We have installed a total of 23 units of four manufacturers in the field test of over four years (from 2007 to 2010), of which 14 units are still under operation as of April 30, 2012 (table 1). And the operating time has reached 18,600 hours at the longest, with 268,500 hours in total of 23 units. We have acquired the knowledge as shown below during the field tests conducted at general residences which we selected to reflect a variety of electrical and hot water demands (Figure 2). (1) Residential SOFC co-generation system contributes to the saving the preliminary energy consumptions and CO2 emissions by households in Japan (Figure 3, Figure 4). (2) SOFC system shows high electricity efficiency exceeding 45%LHV, and the transition of efficiency indicates that the durability of SOFC system including cell stack is estimated to be almost practical use (Figure 5). (3) SOFC system shows high reliability because of its simple system configuration. We will report the detailed results of SOFC field tests based on the latest data. Acknowledgments Finally, we would like to express our appreciation to NEDO, as this report is prepared mainly based on the results of the project supported by NEDO. Figure 2 Residential Demand (/Month) References [1] Solid Oxide Fuel Cell demonstrative research project final report (2011)
http://www.nef.or.jp/sofc/share/pdf/h22y.pdf [2] Y. KAWABATA, T.SEYAMA, T.SOBUE, International Gas Union Research Conference
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2011
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Development and Field Test of Residential SOFC Co-generation System with All-ceramics-segmented Cells
Assessment of the Performance of Fuel Cells and Batteries
Authors: Williams Mark C. , Suzuki Ai , Miyamoto Akira
Published: June 2013

The fuel cell together with a finite amount of fuel and oxidant is conceptually a battery. The stationary fuel cell in many applications is anticipated to be a 40,000 hour primary battery. Fuel cells are used for longer term operations or missions, the common battery for shorter term. Because of the short battery life, regenerablility is an important and desirable battery feature. Like a battery, some fuel cells are reversible or regenerable or rechargeable (electrolysis), but the development of regenerable fuel cells is not as imperative. While the perfect fuel cell would undergo no degradation, practical fuel cells, like batteries, will degrade. During battery discharge in a single cycle, degradation cannot be readily separated from power output. In the battery degradation can be seen definitively, macroscopically cycle-to-cycle. In the fuel cell, perhaps unlike a battery, the mechanism of degradation may not depend on current density of operation. The life, and hence capacity, of a degrading fuel cell depends on how the fuel cell is operated.
Visualization of Water Distribution in PEFC Short Stack
Authors: Takeda Atsushi , Yamauchi Makoto , Sugiura Kimihiko
Published: June 2013

Polymer electrolyte fuel cells (PEFCs) have water management issues, such as flooding and plugging. We confirmed by two-pole simultaneous image measurements that flooding and plugging in the anode gas channel occur during low-humidity conditions, when water is transported from the cathode to the anode through the membrane. A commercialized PEFC typically stacks two or more single cells. PEFC stacks have specific issues, such as different flow distributions and temperature distributions in the different cells. The amount of gas supplied to each cell of the stack depends on the energy loss of the fluid, and heat concentrates in the center of the stack by an exothermic reaction. Therefore, the distribution of the water produced in the cell of the stack must be different from that of a single cell. However, the gas channel in the stack cannot be directly observed with a video camera, such as that typically used in a single cell. Therefore, we conducted this study to observe the water distribution in the gas channel inside a PEFC short stack using a visualization cell with three pinpoint windows.