bluuebunny/crossref_metadata_2025 huggingface dataset:
Four types of anti-politics: Insights from the Italian case
Authors: Mete Vittorio
Published: February 2010

The wordantipolitica(‘anti-politics’) is widely used in contemporary Italian political debate. The concept of ‘anti-politics’ is also frequently used by social scientists in explaining the Italian political transition that took place during the 1990s and analysing the current political situation. In spite of this wide use, sociopolitical literature does not provide a consensual definition of the term. As result, the semantic field of the concept as yet appears poorly defined. This article provides a detailed look at the use of the term ‘anti-politics’ in the sociopolitical literature. Structuring the analysis around some basic conceptual distinctions, the article proposes a taxonomy of the meanings related to the term ‘anti-politics’, highlighting four different meanings of the concept. Referring in particular to the Italian political system, the article provides examples of the meanings of the concept of ‘anti-politics’ using phenomena occurring in the peninsula during the 1990s – phenomena which were central to the increasing use of the term in Italy during that decade.
A Eurosceptic vision in a europhile country: The case of the Lega Nord
Authors: Huysseune Michel
Published: February 2010

As a consequence of Italy's integration in the EMU in 1998, the Lega Nord shifted from a pro-European to a Eurosceptic position. The Lega's Eurosceptic vision combines a strong identification with Europe with a hostile attitude towards the institutions of the EU. Identification with Europe expresses in the first place the party's geopolitical view of Padania as a European and hence modern and entrepreneurial region. Its critique of the EU incorporates numerous, sometimes contradicting influences such as the neo-liberal vision of a free-trade based Europe with minimal rules and regulations, and a protectionist defence of northern Italian economic interests. It is in particular the party's institutional vision that attributes centrality to the right of Padania to autonomy and self-government which leads to its rejection of the centralism and dirigism of the European Union.
The Republic after Berlusconi: Some reflections on historiography, politics and the political use of history in post-1994 Italy
Authors: Orsina Giovanni
Published: February 2010

The Italian political crisis of 1993–1994 and the new political dynamics to which it gave rise, and which persist today, have strongly shaped both public debate and historiographical reflection on the Italian Republic. This article assesses the impact of the political changes of the post-1994 period (and notably Berlusconi's entry into politics) on the debate over the so-called First Republic, with regard to: Italian national identity in the post-Fascist period; the functioning of the political system, especially in relation to the role of the political parties; anti-Fascism and its internal divisions; communism and anti-communism.
Advanced glycation end‐products, anti‐hypertensive treatment and diastolic function in patients with hypertension and diastolic dysfunction
Authors: Hartog Jasper W.L. , van de Wal Ruud M. , Schalkwijk Casper G. , Miyata Toshio , Jaarsma Wybren , Plokker H.W. Thijs , van Wijk Leen M. , Smit Andries J. , van Veldhuisen Dirk J. , Voors Adriaan A.
Published: February 2010

Aims

To investigate the relationship between advanced glycation end‐products (AGEs) and diastolic function and the response to blood pressure treatment in patients with hypertension and diastolic dysfunction.

Methods and results

Data were analysed from 97 patients (aged 65 ± 10 years, 36% male) who were randomly assigned to 6 months open‐label treatment with either eprosartan on top of other anti‐hypertensive drugs (n = 47) or other anti‐hypertensive drugs alone (n = 50). Tissue AGE accumulation was measured using a validated skin‐autofluorescence (skin‐AF) reader (n = 26). Plasma Nɛ‐(carboxymethyl)lysine (CML), Nɛ‐(carboxyethyl)lysine (CEL), and pentosidine were measured by LC‐MS/MS and HPLC. Diastolic function was assessed using echocardiography. Blood pressure was reduced from 157/91 to 145/84 mmHg (P < 0.001) in the eprosartan group and from 158/91 to 141/83 mmHg (P < 0.001) in the control group. No effect of eprosartan was found on AGE levels. In patients with baseline skin‐AF < median, E/A ratio (P = 0.04) and the mean peak early‐diastolic filling velocity (E′) improved (P = 0.001). In contrast, in patients with skin‐AF levels > median, E/A ratio (P = 0.84) and mean E′ (P = 0.32) remained unchanged.

Conclusion

Although eprosartan did not decrease levels of AGEs, patients with lower skin‐AF at baseline showed a larger improvement in diastolic function in response to either anti‐hypertensive treatment compared with patients with higher skin‐AF.
Efficient recovery of dysferlin deficiency by dual adeno-associated vector-mediated gene transfer
Authors: Lostal William , Bartoli Marc , Bourg Nathalie , Roudaut Carinne , Bentaïb Azeddine , Miyake Katsuya , Guerchet Nicolas , Fougerousse Françoise , McNeil Paul , Richard Isabelle
Published: February 2010

Deficiency of the dysferlin protein presents as two major clinical phenotypes: limb–girdle muscular dystrophy type 2B and Miyoshi myopathy. Dysferlin is known to participate in membrane repair, providing a potential hypothesis to the underlying pathophysiology of these diseases. The size of the dysferlin cDNA prevents its direct incorporation into an adeno-associated virus (AAV) vector for therapeutic gene transfer into muscle. To bypass this limitation, we split the dysferlin cDNA at the exon 28/29 junction and cloned it into two independent AAV vectors carrying the appropriate splicing sequences. Intramuscular injection of the corresponding vectors into a dysferlin-deficient mouse model led to the expression of full-length dysferlin for at least 1 year. Importantly, systemic injection in the tail vein of the two vectors led to a widespread although weak expression of the full-length protein. Injections were associated with an improvement of the histological aspect of the muscle, a reduction in the number of necrotic fibers, restoration of membrane repair capacity and a global improvement in locomotor activity. Altogether, these data support the use of such a strategy for the treatment of dysferlin deficiency.
Ventral lateral geniculate input to the medial pons is necessary for visual eyeblink conditioning in rats
Authors: Halverson Hunter E. , Freeman John H.
Published: February 2010

The conditioned stimulus (CS) pathway that is necessary for visual delay eyeblink conditioning was investigated in the current study. Rats were initially given eyeblink conditioning with stimulation of the ventral nucleus of the lateral geniculate (LGNv) as the CS followed by conditioning with light and tone CSs in separate training phases. Muscimol was infused into the medial pontine nuclei (MPN) after each training phase to examine conditioned response (CR) retention to each CS. The spread of muscimol infusions targeting the MPN was examined with fluorescent muscimol. Muscimol infusions into the MPN resulted in a severe impairment in retention of CRs with the LGNv stimulation and light CSs. A less severe impairment was observed with the tone CS. The results suggest that CS information from the LGNv and light CSs is relayed to the cerebellum through the MPN. Retrograde tracing with fluoro-gold (FG) showed that the LGNv and nucleus of the optic tract have ipsilateral projections to the MPN. Unilateral inputs to the MPN from the LGNv and nucleus of the optic tract may be part of the visual CS pathway that is necessary for visual eyeblink conditioning.
Assessment of the role of MAP kinase in mediating activity-dependent transcriptional activation of the immediate early gene Arc/Arg3.1 in the dentate gyrus in vivo
Authors: Chotiner Jennifer K. , Nielson Jessica , Farris Shannon , Lewandowski Gail , Huang Fen , Banos Karla , de Leon Ray , Steward Oswald
Published: February 2010

Different physiological and behavioral events activate transcription of Arc/Arg3.1 in neurons in vivo, but the signal transduction pathways that mediate induction in particular situations remain to be defined. Here, we explore the relationships between induction of Arc/Arg3.1 transcription in dentate granule cells in vivo and activation of mitogen-activated protein (MAP) kinase as measured by extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation. We show that ERK1/2 phosphorylation is strongly induced in dentate granule cells within minutes after induction of perforant path long-term potentiation (LTP). Phospho-ERK staining appears in nuclei within minutes after stimulation commences, and ERK phosphorylation returns to control levels within 60 min. Electroconvulsive seizures, which strongly induce prolonged Arc/Arg3.1 transcription in dentate granule cells, induced ERK1/2 phosphorylation in granule cells that returned to control levels within 30 min. Following 30, 60, and 120 min of exploration in a novel complex environment, Arc/Arg3.1 transcription was activated in many more granule cells than stained positively for p-ERK at all time points. Although Arc/Arg3.1 transcription was induced in most pyramidal neurons in CA1 following exploration, very few pyramidal neurons exhibited nuclear p-ERK1/2 staining. Local delivery of U0126 during the induction of perforant path LTP blocked transcriptional activation of Arc/Arg3.1 in a small region near the injection site and blocked Arc/Arg3.1 protein expression over a wider region. Our results indicate that activation of Arc/Arg3.1 transcription in dentate granule cells in vivo is mediated in part by MAP kinase activation, but other signaling pathways also contribute, especially in the case of Arc/Arg3.1 induction in response to experience.
Perirhinal cortex is necessary for acquiring, but not for retrieving object–place paired association
Authors: Jo Yong Sang , Lee Inah
Published: February 2010

Remembering events frequently involves associating objects and their associated locations in space, and it has been implicated that the areas associated with the hippocampus are important in this function. The current study examined the role of the perirhinal cortex in retrieving familiar object–place paired associates, as well as in acquiring novel ones. Rats were required to visit one of two locations of a radial-arm maze and choose one of the objects (from a pair of different toy objects) exclusively associated with a given arm. Excitotoxic lesions of the perirhinal cortex initially impaired the normal retrieval of object–place paired-associative memories that had been learned presurgically, but the animals relearned gradually to the level of controls. In contrast, when required to associate a novel pair of objects with the same locations of the maze, the same lesioned rats were severely impaired with minimal learning, if any, taking place throughout an extensive testing period. However, the lesioned rats were normal in discriminating two different objects presented in a fixed arm in the maze. The results suggest that the perirhinal cortex is indispensable to forming discrete representations for object–place paired associates. Its role, however, may be compensated for by other structures when familiar object–place paired associative memories need to be retrieved.
Role of amygdala and hippocampus in the neural circuit subserving conditioned defeat in Syrian hamsters
Authors: Markham Chris M. , Taylor Stacie L. , Huhman Kim L.
Published: February 2010

We examined the roles of the amygdala and hippocampus in the formation of emotionally relevant memories using an ethological model of conditioned fear termed conditioned defeat (CD). Temporary inactivation of the ventral, but not dorsal hippocampus (VH, DH, respectively) using muscimol disrupted the acquisition of CD, whereas pretraining VH infusions of anisomycin, a protein synthesis inhibitor, failed to block CD. To test for a functional connection between the VH and basolateral amygdala (BLA), we used a classic functional connectivity design wherein injections are made unilaterally in brain areas either on the same or opposite sides of the brain. A functional connection between the BLA and VH necessary for the acquisition of CD could not be found because unilateral inactivation of either BLA alone (but not either VH alone) was sufficient to disrupt CD. This finding suggested instead that there may be a critical functional connection between the left and right BLA. In our final experiment, we infused muscimol unilaterally in the BLA and assessed Fos immunoreactivity on the contralateral side following exposure to social defeat. Inactivation of either BLA significantly reduced defeat-induced Fos immunoreactivity in the contralateral BLA. These experiments demonstrate for the first time that whereas the VH is necessary for the acquisition of CD, it does not appear to mediate the plastic changes underlying CD. There also appears to be a critical interaction between the two BLAs such that bilateral activation of this brain area must occur in order to support fear learning in this model, a finding that is unprecedented to date.
Recognition memory: Adding a response deadline eliminates recollection but spares familiarity
Authors: Sauvage Magdalena M. , Beer Zachery , Eichenbaum Howard
Published: February 2010

A current controversy in memory research concerns whether recognition is supported by distinct processes of familiarity and recollection, or instead by a single process wherein familiarity and recollection reflect weak and strong memories, respectively. Recent studies using receiver operating characteristic (ROC) analyses in an animal model have shown that manipulations of the memory demands can eliminate the contribution of familiarity while sparing recollection. Here it is shown that a different manipulation, specifically the addition of a response deadline in recognition testing, results in the opposite performance pattern, eliminating the contribution of recollection while sparing that of familiarity. This dissociation, combined with the earlier findings, demonstrates that familiarity and recollection are differentially sensitive to specific memory demands, strongly supporting the dual process view.
Role of the basolateral amygdala in the reinstatement and extinction of fear responses to a previously extinguished conditioned stimulus
Authors: Laurent Vincent , Westbrook R. Frederick
Published: February 2010

Four experiments used rats to study the role of the basolateral amygdala (BLA) in the reinstatement and extinction of fear responses (freezing) to a previously extinguished conditioned stimulus (CS). In Experiment 1, BLA inactivation before pairing the extinguished CS with the shock unconditioned stimulus (US) or before US-alone exposure impaired the restoration and the reinstatement of fear responses to the extinguished CS. In Experiment 2, BLA inactivation before extinction impaired long-term inhibition of fear responses, but its inactivation before extinction of fear responses restored by CS–US pairing did not impair long-term inhibition. In Experiment 3, BLA inactivation before extinction of fear responses or before the extinction of fear responses reinstated by US-alone exposure impaired long-term inhibition. In Experiment 4, BLA inactivation did not impair long-term inhibition of fear responses reinstated by US-alone exposure if the context where the US-alone exposure occurred had been previously extinguished. These results confirm that the BLA is critical for both learning fear and fear inhibition, but not for relearning this inhibition. The results are consistent with the view that reinstatement is due to the extinguished CS being tested in a dangerous context and are discussed in terms of a contemporary neural model of fear inhibition.
Synapsin is selectively required for anesthesia-sensitive memory
Authors: Knapek Stephan , Gerber Bertram , Tanimoto Hiromu
Published: February 2010

Odor-shock memory in Drosophila melanogaster consists of heterogeneous components each with different dynamics. We report that a null mutant for the evolutionarily conserved synaptic protein Synapsin entails a memory deficit selectively in early memory, leaving later memory as well as sensory motor function unaffected. Notably, a consolidated memory component remaining after cold-anesthesia is not impaired, suggesting that only anesthesia-sensitive memory [ASM] depends on Synapsin. The lack of Synapsin does not further impair the memory deficit of mutants for the rutabaga gene encoding the type I adenylyl cyclase. This suggests that cAMP signaling, through a Synapsin-dependent mechanism, may underlie the formation of a labile memory component.
Blockade of dopamine activity in the nucleus accumbens impairs learning extinction of conditioned fear
Authors: Holtzman-Assif Orit , Laurent Vincent , Westbrook R. Frederick
Published: February 2010

Three experiments used rats to investigate the role of dopamine activity in learning to inhibit conditioned fear responses (freezing) in extinction. In Experiment 1, rats systemically injected with the D2 dopamine antagonist, haloperidol, froze more across multiple extinction sessions and on a drug-free retention test than control rats. In Experiment 2, rats extinguished under an intracerebroventricular (ICV) infusion of haloperidol suppressed fear responses across extinction but froze more on a subsequent drug-free retention test than control rats. In Experiment 3, rats extinguished under an infusion of haloperidol in the nucleus accumbens were impaired in suppressing fear responses across extinction and froze more on subsequent drug-free retention test than control rats. These results show that learning to inhibit fear responses in extinction requires dopamine activity in the nucleus accumbens. They were interpreted to mean that dopaminergic activity in the nucleus accumbens regulates the prediction error required for learning to inhibit fear responses in extinction.
Increased expression of calcium‐sensing receptors induced by ox‐LDL amplifies apoptosis of cardiomyocytes during simulated ischaemia–reperfusion
Authors: Guo Jin , Li Hong‐Zhu , Zhang Wei‐Hua , Wang Lu‐Chuan , Wang Li‐Na , Zhang Li , Li Guang‐Wei , Li Hong‐Xia , Yang Bao‐Feng , Wu Lingyun , Wang Rui , Xu Chang‐Qing
Published: February 2010

1. Acute myocardial infarction (AMI) is strongly associated with atherosclerosis, and is responsible for significant morbidity and mortality worldwide. The pathogenic mechanisms that underlie atherosclerosis and AMI are undefined at present. The calcium‐sensing receptor (CaSR) is a member of the superfamily of G‐protein coupled receptors. It has been demonstrated previously that the expression of CaSR is increased in atherosclerotic cardiac tissue of rats. It has also been suggested that CaSR has a crucial role in cardiac ischaemia–reperfusion injury, apoptosis and hypertrophy. However, it remains to be determined whether an increase in the expression of CaSR influences the sensitivity of cardiomyocytes to AMI.

2. The present study used cultured ventricular cardiomyocytes from neonatal rats to investigate the effect of oxidized low‐density lipoprotein (ox‐LDL), ischaemia–reperfusion, GdCl3 (an agonist of CaSR) and NPS‐2390 (an antagonist of CaSR) on the expression of CaSR. The amount of apoptosis, alterations in the morphology of the cells, the intracellular calcium concentration ([Ca2+]i) and components of critical mitochondrial pathways were also analysed.

3. Cardiomyocytes treated with ox‐LDL showed upregulated expression of CaSR, cytochrome c (cyt‐c), Bax and activated caspase 3 (17 kD) and downregulated expression of Bcl‐2, as well as elevated [Ca2+]i and apoptosis. Application of GdCl3 augmented these effects, and NPS‐2390 decreased the expression of CaSR and reduced apoptosis.

4. In conclusion, ox‐LDL was found to increase the expression of CaSR in a manner that was dependent on time and dose. It also augmented apoptosis during simulated ischaemia–reperfusion in cultured ventricular cardiomyocytes from neonatal rats.
Vitamin D and increasing incidence of type 1 diabetes—evidence for an association?
Authors: Hyppönen E.
Published: February 2010

There has been an important shift in the views about the actions of vitamin D during the past decade. In addition to its well‐established role in the regulation of calcium metabolism, vitamin D deficiency has been associated with the risk of several extra‐skeletal diseases, including type 1 diabetes among other chronic conditions. It is notable that 1,25(OH)2D is known to regulate the expression of over 200 different genes, including the ones related to apoptosis and immune modulation. Increased vitamin D intake is currently considered as one of the most promising candidates for the prevention of type 1 diabetes, and it has been suggested that changes in vitamin D intake during the past decades have contributed to the recent trends in the incidence of the disease. This study reviews the evidence for the role of vitamin D in type 1 diabetes development, demonstrating that support has been obtained from various lines of investigation and that the possible biological mechanisms are plausible. However, much of the evidence has been obtained from animal experiments or observational studies in humans and there is an urgent need for well‐designed, randomized, controlled trials to show whether the observed associations are indeed causal.
Cultural Criminology and Sex Work: Resisting Regulation through Radical Democracy and Participatory Action Research (PAR)
Authors: O'Neill Maggie
Published: February 2010

Taking a feminist cultural criminological analysis to the regulation of sex work in the United Kingdom, this paper argues against the dominant deviancy and the increasingly abolitionist criminal justice model for regulating sex work. The paper begins by offering a critique of the dominant regulatory regimes which have operated since the Victorian era, amended in part in the 1950s with Wolfenden, and currently being reinscribed with the Home Office strategy on prostitution and various pieces of legislation. The focus is specifically upon research with female sex workers and the usefulness of using Participatory Action research methodologies (PAR) with sex workers, agencies, and policy makers in order to foreground the diverse voices and experiences of sex workers, challenge the current focus on abolitionist criminal justice regimes and outcomes, and offer an alternative framework for a cultural materialist analysis of sex work, drawing upon the work of Nancy Fraser.
Role of vision on early motor development: lessons from the blind
Authors: Prechtl Heinz FR , Cioni Giovanni , Einspieler Christa , Bos Arend F , Ferrari Fabrizio
Published: February 2010

For a better understanding of the contribution vision makes to the development of other sensory systems and to movement and posture, we studied effects of early blindness by examining video recordings of 14 totally blind infants. Infants were born at term or preterm and showed no evidence of brain damage. During preterm and term periods no noticeable changes in motor activity were observed. Around 2 months postterm all infants showed clear delay in head control and abnormal, exaggerated type of ‘fidgety movements’. Later, postural control was characterized by a prolonged period of ataxic features. Results indicate a lack of normal calibration exerted by vision on proprioceptive and vestibular systems. Early visuomotor coordination such as coordinated eye‐head scanning and head orientating were present but disappeared after several weeks.
AN ATYPICAL LOCALISATION OF TUBERCULOSIS INFECTION IN PATIENTS UNDERGOING HAEMODIALYSIS: A CASE REPORT
Authors: Kayabasi Hasan , Sit Dede , Kadiroglu Ali Kemal , Yilmaz Zulfukar , Bukte Yasar
Published: February 2010

Spinal tuberculosis (TB) is a rare skeletal system localisation of TB in haemodialysis patients. In this paper, a case of Pott's disease with a psoas muscle abscess is reported. The patient had been on the dialysis programme for five years and was complaining of back pain, weight loss and weakness, which were investigated. A thoracolumbar magnetic resonance imaging showed multiple paravertebral abscesses invading the psoas muscle. TB diagnosis was made by microbiological analysis of specimen, which was obtained by fine needle aspiration under computerised tomography guidance.
Biomechanical Evaluation of Short-Segment Posterior Instrumentation With Crosslinks in an Unstable Human Burst Fracture Model
Authors: Wahba George M. , Bhatia Nitin N. , Lee Thay Q.
Published: February 2010

Unstable thoracolumbar burst fractures are serious injuries and their management remains controversial. Some authors advocate the use of short-segment posterior instrumentation (SSPI) for certain burst fractures which offers several benefits including preservation of motion segments; however, clinical studies have shown mixed results. Whether crosslinks contribute sufficient stability to this construct has not been determined, therefore the objective of this study was to evaluate the biomechanical characteristics of short-segment posterior instrumentation, with and without crosslinks, in an unstable human burst fracture model.
Numerical Simulation of Metal-Supported Solid Oxide Fuel Cell (mSOFC)
Authors: Phoocharoen Niwat , Charoensuk Jarruwat
Published: February 2010

In this paper we present the numerical results of planar solid oxide fuel cell at the level of membrane electrode assembly, MEA. The study is aimed at evaluating the performance of metal-supported design versus the conventional anode-cathode support under co-flow and counter-flow conditions. We have found that the value of peak temperature is lower therefore better temperature distribution is achieved for metal supported design with counter-flow configuration. Moreover the corresponding current density at maximum power is also higher with this configuration. This later design however possesses greater concentration loss or over-potential due to fuel concentration gradient at the porous layer of supporting metal. To compensate this difference, we have proposed the modification of the current collector at the cathode side to reduce the ohmic loss, while minimizing the concentration loss at the reaction site. The result of this modification suggests an improvement of maximum power density from 0.984 W/cm2 to 1.034 W/cm2. This is slightly less than the value of an original version for only 0.132%. At this counter-flow configuration the value of peak temperature is also lower as compared with its counterpart with co-flow configuration.
Testing Different Catalysts for a Vapor-Fed PBI-Based Direct Ethanol Fuel Cell
Authors: Lobato J. , Can˜izares P. , Rodrigo M. A. , Linares J. J. , Sa´nchez-Rivera B.
Published: February 2010

With the aim of improving the ethanol oxidation in fuel cells, researchers have developed numerous catalysts to break up the C-C bond. Most of the tests have been carried out at low temperature, using Nafion membrane as electrolyte. The cell performance of the Direct Ethanol Fuel Cells (DEFCs) at low temperature is still far from its industrial application. To improve the DEFC power density, high temperature operation (150–200 °C) has been suggested to promote the complete oxidation of ethanol. Thus, three different catalysts (Pt-Ru (1:1), Pt-Sn (1:1) and Pt-Sn-Ru (1:1:0.3), all of them supported on both non-activated and activated carbon were tested in H3PO4 doped PBI-based fuel cell, using vapour fed ethanol, operating in the range of 150–200 °C, and high ethanol concentration 6.7 M. The catalyst were synthesized using NaBH4 as reducing agent and were characterized by XRD, ICP-AES and TPR analyses. The best performance was reached at the highest temperature and with the catalyst based on Pt-Ru. The best results for the Ru-based catalyst can be explained by the higher level of alloying reached for the Ru than for Sn, which modifies the crystalline structure of Pt and enhances the activity oxidation of ethanol and of intermediates that are generated during the oxidation of ethanol.
3-D Multiphase Cold Start Model for PEMFCs
Authors: Jiao Kui , Li Xianguo
Published: February 2010

A three-dimensional multiphase model has been developed to simulate the cold start processes in a polymer electrolyte membrane fuel cell (PEMFC). This model uniquely includes the water freezing in the membrane, the non-equilibrium mass transfer between the water in the ionomer and the water (vapour, liquid and ice) in the pore region of the catalyst layer (CL), and the water freezing and melting in the CL and gas diffusion layer (GDL). Numerical simulations have been conducted for a single PEMFC starting from different subzero temperatures to investigate both the failed and successful cold start processes. Numerical results indicate that the ohmic heat is the largest heating source at low cell voltages. It is observed that water freezes first in the cathode CL under the land, and ice melts first in the CLs under the flow channel, the melted water in the anode is also removed faster than in the cathode.
Investigation of Mixed Conducting Cathode for Metal-Supported SOFC
Authors: Kim Yu-Mi , Bae Joongmyeon
Published: February 2010

Metal-supported solid oxide fuel cell (SOFC) is a promising concept in solving serious problems associated with current SOFC design. Metal-supported SOFC have many advantages as compared to current SOFC such as easy sealing, mechanical durability and cost reduction. However, they have also disadvantages such as diffusion of metallic components between metal-substrate and anode, corrosion of metal at high temperatures. Due to the cell fabrication and oxidation of metal substrate, unsintered cathode with high electrochemical activity at operating temperature is essential in order to obtain the better performance in the metal-supported SOFC. For this purpose, mixed conducting cathode materials for metal-supported SOFC were investigated by using SEM, XRD, EIS and particle size distribution (PSD) measurement. From the results of half cell test using 8YSZ electrolyte and SEM images, it was observed that (Ba,Sr)(Co,Fe)O3-δ electrode showed the better electrochemical performance and sinterability at 1073 K than other conventional cathode material. It was also concluded from the long-term test that the buffer layer between electrolyte and cathode is necessary in order to eliminate the chemical reaction between the 8YSZ electrolyte and the cathode.
Graduated Flow Resistance Through a GDL in a Novel PEM Stack
Authors: Caston Terry B. , Bhamidipati Kanthi L. , Carney Haley , Harris Tequila A. L.
Published: February 2010

The goal of this study is to design a gas diffusion layer (GDL) for a polymer electrolyte membrane (PEM) fuel cell with a graduated permeability, and therefore a graduated resistance to flow throughout the GDL. It has been shown that using conventional materials the GDL exhibits a higher resistance in the through-plane direction due to the orientation of the small carbon fibers that make up the carbon paper or carbon cloth. In this study, a GDL is designed for an unconventional PEM fuel cell stack, where the reactant gases are supplied through the side of the GDL rather than through flow field channels, which are machined into a bipolar plate. The effects of changing in-plane permeability, through-plane permeability, and thickness of the GDL on the expected current density distribution at the catalyst layer are studied. Three different thicknesses are investigated, and it is found that as GDL thickness increases, more uniform reactant distribution over the face of the GDL is obtained. Results also show that it is necessary to design a GDL with a much higher in-plane resistance than through-plane resistance for the unconventional PEM stack studied.
Inorganic-Nano-Fiber-Based Catalyst for Hydrogen Fuel Cells With Superior Performance
Authors: Zhu Yimin , Stefan Ionel , Qian Baixin , Goldman Jay , Hofler Jurgen , Hartlove Jason
Published: February 2010

In this paper we report on a novel, cost-effective fuel cell catalyst solution that meets performance as well as reliability goals set forth by the Department Of Energy for transportation applications for 2010. Our fuel cell catalyst technology is based on an inorganic, conductive nano-fiber network decorated with Pt or Pt-alloy nano-particles. The nano-fibers have diameters in the 10s of nanometers and aspect ratios of ∼100:1. The resulting large surface area, high chemical activity, and efficient electron and proton transport in the membrane electrode assembly (MEA) allow for ultra-low material loading at very high performance. Specifically, with a total loading (anode and cathode) of only 0.2mg/cm2, we have demonstrated a performance of 0.25g/kW at 0.65V exceeding the 2010 DOE goal of 0.3g/kW. We also met the DOE target for power density of 0.25 W/cm2 at 0.8V. Very important for practical applications, the initial reliability tests show that our inorganic nano-fiber-based catalysts have a lifetime performance far superior to carbon-based approaches.
Current Distribution in a Polymer Electrolyte Membrane Fuel Cell Under Flooding Conditions
Authors: Jamekhorshid A. , Karimi G. , Li X.
Published: February 2010

Non-uniform current distribution in polymer electrolyte membrane fuel cells results in local over-heating, accelerated ageing, and lower power output than expected. This issue is very critical when fuel cell experiences water flooding. In this work, the performance of a PEM fuel cell is investigated under cathode flooding conditions. A partially flooded GDL model is proposed to study local current density distributions along flow fields over a wide range of cell operating conditions. The model results show as cathode inlet humidity and/or cell pressure increase the average current density for the unflooded portions of the cell increases but the system becomes more sensitive to flooding. Operating the cell at higher temperatures would lead to higher average current densities and the chance of system being flooded is reduced. In addition, higher cathode stoichiometries prevent system flooding but the average current density remains almost constant.
Condensation Based Pore Network Modelling of Water Transport in Hydrophobic PEM Fuel Cell GDLs
Authors: Hinebaugh James , Bazylak A.
Published: February 2010

In this work, a novel pore network model is employed to simulate water transport originating from condensation in the polymer electrolyte membrane (PEM) fuel cell gas diffusion layer (GDL). Liquid water transport follows the rules of invasion percolation with trapping, where two mobile phases are considered. Flow conditions are based on dynamic pressure changes in the network. The GDL is assumed to be a hydrophobic pore network, where capillary forces dominate over gravitational and viscous forces. The model follows a condensation based algorithm that begins with a single nucleation site from where liquid water spreads with continuing condensation. To account for a humidity gradient within the GDL, water flow is assumed to originate from condensation occurring in pores facing the cathode catalyst layer. Modelling parameters and their effect on the saturation profile are discussed. Little impact was found on the saturation profile when trapping logic was made more sophisticated, recognizing conditions leading to air trapping in a single throat. It is shown that saturation profiles for slow flow (i.e. slow condensation rates) can be predicted with reasonable accuracy from a known throat topology alone. However, as condensation rates are increased, raising network viscous forces to levels comparable to network capillary forces, the flow patterns begin to depend on a number of variables such as pore sizes and pore filling rates. At such condensation rates, flow patterns show high sensitivity to variance in condensation rates and become much less predictable from simple geometries.
Low-Temperature Prepared Multi-Elements Doped CeO2 Electrolyte
Authors: Chang Horng-Yi , Wang Yao-Ming
Published: February 2010

CeO2 materials doped with the di- or tri-valent metals possess high oxide ionic conductivity at low temperature for potential electrolyte use in intermediate temperature solid oxide fuel cell (SOFC). However, multi-elements doped CeO2-based electrolyte, (La1-x-ySrxBay)0.175Ce0.825O2-δ (LSBC) in this work, with pure phase is difficultly synthesized at low calcination temperature. High sintering temperature, e.g. > 1500°C, is also needed in conventional mixed oxide method. In this work, nanoparticles less than 50nm of LSBC can be prepared by solution-evaporation method at constant temperature. Pure fluorite crystal structure can be obtained lower than 700°C. The optimal mole ratio of LSBC/citric acid in prepared solution is 1/2 to achieve homogeneous composition and pure phase of LSBC. Small grain size of about 1μm average is observed for 1300°C-microwave sintered LSBC by solution-evaporation method. The ionic conductivity of 1400°C-conventional sintered and 1300°C-microwave sintered LSBC prepared by solution-evaporation method is about 0.006 S/cm at 600°C but less than 0.004 S/cm at 600°C even for 1500°C-conventional sintered LSBC prepared by mixed oxide method.
A Study on Liquid Water Removal From Gas Diffusion Layer by Pressure Gradient
Authors: Park Jae Wan , Jiao Kui , Li Xianguo
Published: February 2010

Water removal from the gas diffusion layer (GDL) is crucial for the stable and efficient operation of proton exchange membrane (PEM) fuel cells. The static pressure gradient induced by reactant flow in the flow channel is one of the main driving potential for the liquid water to be drawn from the GDL. In the PEM fuel cells with interdigitated and serpentine flow channels, considerable amount of reactant flows through the GDL due to the pressure gradient between adjacent flow channels. Such pressure gradient and resultant cross flow may also play an important role for the water removal from GDL during operation. In this work, liquid water transport in the GDL is studied numerically to investigate the effect of pressure gradient and the surface hydrophobicity on the water removal from the GDL. The fibrous porous structure of carbon paper is modeled by distributing impermeable cylinders in random directions. Unsteady two phase simulation has been performed utilizing a commercial software FLUENT based on the volume of fluid (VOF) scheme to determine the phase boundary. The permeability of the numerical medium is compared with the experimental measurements in literature resulting in a good agreement. It is shown that the surface hydrophobicity of the fiber is a dominant parameter to initiate the water transport in the GDL for the pressure gradient in typical operating conditions. Cross flow occurring in the serpentine flow channels may be effective to get rid of the liquid water in the gas diffusion layer. Present work may provide useful data to design and optimize the important properties of gas diffusion layer such as permeability and surface hydrophobicity.
The Need to Address Aeromechanical T&E Requirements During Engine Inlet Distortion Testing
Authors: Mihigo Jean Paul , Malloy Donald J. , Vining Charles R. , McNiel Charles M. , Kidman David S. , Stevens Craig A. , Monaco Jeffrey F.
Published: February 2010

The need to address aeromechanical measurement requirements to fully characterize the impact of engine inlet distortion on the aeromechanical response of turbine engine fan blades is highlighted. Vibratory responses of a turbine engine fan with two distortion patterns are analyzed and compared. Fourier analysis is used to characterize the harmonic content of the vibration through amplitude coefficients associated with engine order. The effect of varying the number and orientation of the pressure distortion rake measurements is also analyzed. The key point presented, which ultimately has implications on the test procedures and the interpretation of the results, is that the number of rakes in the measurement array must be sufficient to accurately resolve the spatial distortion data into per-rev excitation amplitudes.
Prediction of Power Plant Exposure to Economic Losses Through a Property Risk Assessment Methodology
Authors: Orme G. J. , Venturini M.
Published: February 2010

In this paper, a procedure for Risk Assessment, which makes use of two risk indices (PML - Probable Maximum Loss and MFL - Maximum Foreseeable Loss) is applied to power plants to evaluate potential economic losses due to risk exposure for two different loss scenarios (probable and worst-case). The paper is mainly focused on Property Insurance aspects, though Boiler and Machinery Insurance and business interruption are also addressed. First, the procedure is applied to provide a prediction of probable and maximum loss as a function of power output. The results allow an estimate of whether the adoption of risk assessment procedures and devices allows an actual payback for plant owners. Second, the economic loss predicted through the risk assessment procedure is compared against real power plant loss values, taken from published data.
Assessment of the Performance and of the Profitability of CHP Energy Systems Fed by Vegetable Oils
Authors: Bettocchi R. , Cadorin M. , Morini M. , Pinelli M. , Spina P. R. , Venturini M.
Published: February 2010

In this paper, energy and economic analyses of vegetable oil fed energy systems are presented. The paper focuses on the process from oil to energy, while the economic costs of the transformation process of the biomass from field to oil is assumed embodied in the cost of the oils. Five different oils are considered (sunflower, rapeseed, soybean, palm and waste fried oil) as fuels for cogenerative Internal Combustion Engines, also running in combined cycle configuration. In particular, the considered combined cycle is composed of Internal Combustion Engines and Organic Rankine Cycle modules. Energy analyses allow the evaluation of the installed power, of the produced energies, and of the primary energy saving index for different yearly oil mass values. The results of the economic analyses as a function of yearly oil mass are also presented. The cost sources are highlighted in order to point out the major contributors. Moreover, analyses of the limit value of incentive and oil price, in order to guarantee plant profitability, are carried out.
CFD Simulation of Fouling on Axial Compressor Stages
Authors: Morini Mirko , Pinelli Michele , Spina Pier Ruggero , Venturini Mauro
Published: February 2010

Three-dimensional numerical simulations of the effect of fouling on an axial compressor stage were carried out. As a case study, the NASA Stage 37 was considered for the numerical investigation, which was performed by means of a commercial computational fluid dynamic code. The numerical model was validated against the experimental data available from literature. Computed performance maps and main flow field features showed a good agreement with the experimental data. The model was considered representative of a realistic compressor stage. The model was then used to simulate the occurrence of fouling by imposing different combinations of added thickness and surface roughness levels. The effect of fouling on compressor performances was studied. Reductions of the flow coefficient and of the pressure coefficient were found to be of the same order of magnitude of the experimental results found in literature. The model developed seems to overcome some of the limitations of other models found in literature that tend to significantly underestimate the actual values of performance reduction. The numerical results were also used to analyze and debug the stage performance scaling procedure used in stage stacking models in order to represent fouling in multistage compressors. The analysis highlighted that scaling can adequately represent the behavior of the fouled stage in the choked flow region, but it does not capture the reduction of the maximum of the pressure coefficient which is instead revealed by the numerical simulations. Finally, blockage due to fouling was investigated both qualitatively and quantitatively.
Advanced Hydrogen Turbine Development Update
Authors: Bradley Tim , Fadok Joseph
Published: February 2010

Siemens Energy, Inc. was awarded a contract by the U.S. Department of Energy for the first two phases of the Advanced Hydrogen Turbine Development Program. The 3-phase, multi-year program goals are to develop an advanced syngas, hydrogen and natural gas fired gas turbine fully integrated into coal-based Integrated Gasification Combined Cycle (IGCC) plants. The program goal is to demonstrate by 2010 a 2–3% point improvement in combined cycle efficiency above the baseline, 20–30% reduction in combined cycle capital cost and emissions of 2 ppm NOx @ 15% O2. The 2012 goal is for IGCC-based power with carbon capture. Furthermore, by 2015, the goal is to demonstrate a 3–5% point improvement in combined cycle efficiency above the baseline, and 2 ppm NOx @ 15% O2. Recent activities have focused on the initiation of Phase 2. This included developing component level technologies and systems required to meet the 2010 and 2015 project objectives, developing validation test plans for systems and components, performing validation testing of component technologies, and demonstrating through system studies the ability to attain the 2010 and 2015 Turbine Program performance goals. The development effort was focused on engine cycles, combustion technology development and testing, turbine aerodynamics/cooling, modular component technology, materials/coatings technologies and engine system integration/flexibility considerations. The first series of oxidation and coating compatibility testing of modified superalloys was completed. High pressure combustion testing was performed with syngas fuels on a modified premixed combustor. High pressure testing of a second premixed combustion system was also performed. Novel turbine airfoil concept testing continued. Conceptual design reviews and risk analyses were carried out on new gas turbine components. Studies were conducted on gas turbine/IGCC plant integration, fuel dilution effects, varying air integration, plant performance and plant emissions. The results of these studies and developments provide a firm platform for completing the advanced Hydrogen Turbine technologies development in Phase 2.
Experimental Analysis of the Combustion Behavior of a Gas Turbine Burner by Laser Measurement Techniques
Authors: Ax Holger , Stopper Ulrich , Meier Wolfgang , Aigner Manfred , Gu¨the Felix
Published: February 2010

Experimental results from optical and laser spectroscopic measurements on a scaled industrial gas turbine (GT) burner at elevated pressure are presented. Planar laser induced fluorescence on the OH radical and OH* chemiluminescence imaging were applied to natural gas/air flames for a qualitative analysis of the position and shape of the flame brush, the flame front and the stabilization mechanism. The results exhibit two different ways of flame stabilization, a conical more stable flame and a pulsating opened flame. For quantitative results, 1D-laser Raman scattering was applied to these flames and evaluated on an average and single shot basis in order to simultaneously determine the major species concentrations, the mixture fraction and the temperature. The mixing of fuel and air as well as the reaction progress could thus be spatially and temporally resolved, showing differently strong variations depending on the flame stabilization mode and the location in the flame.