bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modular Stack‐Internal Air Humidification Concept‐Verification in a 1 kW Stack
Authors: Santis M. , Schmid D. , Ruge M. , Freunberger S. , Büchi F.N. 
Published: July 2004

AbstractThe analysis of the complete H2/air polymer electrolyte fuel cell system shows that process air humidification is one of the biggest obstacles for a high performance portable system in the kW range. Therefore, a new concept, with passive process air humidification integrated into the stack, has been developed. Humidification in each cell makes the process independent from the number of cells and the operation mode, thus making the concept fully scalable. Without external humidification the system is simpler, smaller, and cheaper. The humidification of the process air is achieved by transfer of product water from the exhaust air, through part of the membrane, to the dry intake air. Tests have shown that cells using the concept of internal humidification and operated with dry air at 70 ° have almost the same performance as when operated with external humidification. A 42‐cell stack with this internal humidification concept was built and integrated into a portable 1 kW power generator system.
How good are the Electrodes we use in PEFC?
Authors: Eikerling M. , Ioselevich A.S. , Kornyshev A.A. 
Published: July 2004

AbstractBasically, companies and laboratories implement production methods for their electrodes on the basis of experience, technical capabilities and commercial preferences. But how does one know whether they have ended up with the best possible electrode for the components used? What should be the (i) optimal thickness of the catalyst layer? (ii) relative amounts of electronically conducting component (catalyst, with support – if used), electrolyte and pores? (iii) “particle size distributions” in these mesophases? We may be pleased with our MEAs, but could we make them better? The details of excellently working MEA structures are typically not a subject of open discussion, also hardly anyone in the fuel cell business would like to admit that their electrodes could have been made much better. Therefore, we only rarely find (far from systematic) experimental reports on this most important issue. The message of this paper is to illustrate how strongly the MEA morphology could affect the performance and to pave the way for the development of the theory. Full analysis should address the performance at different current densities, which is possible and is partially shown in this paper, but vital trends can be demonstrated on the linear polarization resistance, the signature of electrode performance. The latter is expressed through the minimum number of key parameters characterizing the processes taking place in the MEA. Model expressions of the percolation theory can then be used to approximate the dependence on these parameters. The effects revealed are dramatic. Of course, the corresponding curves will not be reproduced literally in experiments, since these illustrations use crude expressions inspired by the theory of percolation on a regular lattice, whereas the actual mesoscopic architecture of MEA is much more complicated. However, they give us a flavour of reserves that might be released by smart MEA design.
Interdealer trading in futures markets
Authors: Locke Peter R. , Sarajoti Pattarake 
Published: July 2004

AbstractTrading amongst dealers on the floor of the futures exchange is examined. Since there is only one trading venue, the common floor area, trading between dealers is carried on in the presence of trades involving customer orders as well, offering a unique setting for testing the effect of inventory on dealer pricing. The findings are that these futures floor traders implicitly engage in interdealer trading as an inventory management tool. Interdealer trades are more likely to be position reducing than other trades, at higher costs than offsetting with customers. In addition, the concept of a dealer hierarchy is developed, where some floor traders, who generally are more successful, profit from their trades with other dealers. Furthermore, these more successful traders are more likely to use interdealer trading in position reducing trades, which is consistent with the existence of a dealer hierarchy. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:923–944, 2004
Conditional OLS minimum variance hedge ratios
Authors: Miffre Joëlle 
Published: July 2004

AbstractThe paper presents a new methodology to estimate time dependent minimum variance hedge ratios. The so‐called conditional OLS hedge ratio modifies the static OLS approach to incorporate conditioning information. The ability of the conditional OLS hedge ratio to minimize the risk of a hedged portfolio is compared to conventional static and dynamic approaches, such as the naïve hedge, the roll‐over OLS hedge, and the bivariate GARCH(1,1) model. The paper concludes that, both in‐sample and out‐of‐sample, the conditional OLS hedge ratio reduces the basis risk of an equity portfolio better than the alternatives conventionally used in risk management. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:945–964, 2004
Towards modelling production of clean fuels: sour gas formation in catalytic cracking
Authors: Villafuerte‐Macías Eduardo F , Aguilar Ricardo , Maya‐Yescas Rafael 
Published: July 2004

AbstractAlthough one important by‐product of fluidised‐bed catalytic cracking of hydrocarbons is the sour gas (mainly hydrogen sulfide), there are no kinetic models to predict its generation. Moreover, if feedstock sulfur is not directed to sour gas, it will be present in gasoline, cycle oils and coke. These products are used as fuels, which could emit sulfur oxides during their combustion. In order to be able to model production of clean fuels, a kinetic scheme that considers sour gas as unmatched product was developed; meanwhile, the sulfur distribution in cracking products is predicted. Model parameters are validated using industrial operating data. This kinetic scheme is employed to model steady state operation of an industrial catalytic cracking riser and to find operating conditions that diminish the sulfur content in fuels. Copyright © 2004 Society of Chemical Industry
Color Doppler imaging of fibroadenomas of the breast with histopathologic correlation
Authors: Strano Selwyn , Gombos Eva C. , Friedland Orith , Mozes Marta 
Published: July 2004

AbstractPurposeThis study was conducted to characterize the spatial distribution of blood vessels in breast fibroadenomas.MethodsWe performed a prospective study to map the anatomic distribution of the vessels in 29 fibroadenomas of the breast using color Doppler sonography. We categorized the detected vessels according to their location in or on the fibroadenoma, counted the different types of vessels, and tested for correlations between vessel distributions or numbers and histopathologic findings.ResultsBlood flow was demonstrated in 24/29 (83%) of fibroadenomas. We found 3 vessel types: feeding vessels, which are prominent vessels leading from the surrounding breast tissue into the fibroadenoma; capsular vessels, which are located within the tissue capsule; and segmental vessels, which are located within the fibrous septa of the fibroadenoma. Capsular and segmental vessels were demonstrated in 23/24 (96%) and 24/24 (100%) of the cases, respectively. Feeding vessels were seen in 12/24 (50%) of the cases. Histopathologic analysis revealed the same location and distribution of the vessels as color Doppler imaging. However, there was no correlation between numbers of vessels counted on sonograms and on histopathologic specimens.ConclusionsExamination of the vascularity demonstrated on color Doppler imaging helps in the diagnosis of benign breast neoplasms such as fibroadenomas. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:317–322, 2004
Sonoanatomy of the Achilles tendon insertion in children
Authors: Grechenig Wolfgang , Mayr Johannes M. , Peicha Gernot , Hammerl Randolf , Schatz Bernd , Grechenig Stefan 
Published: July 2004

AbstractPurposeThe aim of this study was to describe typical age‐related sonographic features of the Achilles tendon and calcaneal apophysis in children, providing a reference for the assessment of heel pathologies during the growth period.MethodsThe calcaneal apophysis and Achilles tendon insertion of 100 children 2 months to 18 years old were examined by high‐frequency gray‐scale and color Doppler sonography along both the longitudinal and transverse planes. The thicknesses of the apophyseal cartilage at the calcaneal tuberosity and of the Achilles tendon were measured. Also, the sonographic appearance of the bone‐cartilage interface was studied.ResultsIn children 2 months to 3 years old, the cartilage of the calcaneal tuberosity apophysis was anechoic, with small scattered echoes. In 19 of these 25 children (76%), the echogenic areas contained at least 1 small vessel, visualized on color Doppler sonography. In 15 of 25 children (60%) 4–6 years old, a wavy interface was noted at the junction of the calcaneus and the apophyseal cartilage.ConclusionsHigh‐frequency sonography can yield reliable information about the bone‐cartilage interface and the Achilles tendon insertion site at the calcaneal tuberosity in children. The sonographic features of the normal heel described here may contribute to improved assessment of pathologies in this anatomic region. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:338–343, 2004
Primary hydatid cyst in the anterior thigh: Sonographic findings
Authors: Koc Zafer , Muhteşem Ağıldere A. , Yalcın Özlem , Pourbagher Aysin , Pourbagher MirAli 
Published: July 2004

AbstractHydatid cysts rarely involve the musculoskeletal system. We present the case of a 23‐year‐old man with a primary hydatid cyst between the femur and the quadriceps muscle in his left thigh. No cysts were located in the adjacent femur or quadriceps muscle. Cyst resection with sparing of the surrounding muscles, combined with anthelmintic therapy, was curative. In regions where hydatidosis is endemic, hydatid cysts should be included in the differential diagnosis of any unusual soft‐tissue swelling. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:358–360, 2004
Primary peripheral T‐cell lymphoma in subcutaneous tissue: Sonographic findings
Authors: Fujii Yasutomo , Shinozaki Takeshi , Koibuchi Harumi , Ono Tomoko , Omoto Kiyoka , Taniguchi Nobuyuki , Itoh Kouichi 
Published: July 2004

AbstractWe describe the sonographic findings in a case of Lennert's lymphoma, a rare type of peripheral T‐cell lymphoma, involving the subcutaneous tissues of the arm. The sonographic appearance was thought to be more helpful than MRI to establish the diagnosis. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:361–364, 2004
Enlargement and hypervascularity of both the epididymis and testis do not exclude involvement with lymphoma or leukemia
Authors: Ishigami Kousei , Yousef‐Zahra Dina M. , Abu‐Yousef Monzer M. 
Published: July 2004

AbstractWe present 3 cases of diffuse infiltration of the testes and epididymides by malignant lymphoma and leukemia. Gray‐scale and color Doppler sonograms showed diffuse hypoechoic enlargement and hypervascularity of the involved testes and epididymides. The authors emphasize that enlargement and hypervascularity of both the epididymis and testis can be caused by lymphomatous/leukemic involvement and is not always indicative of epididymo‐orchitis. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:365–369, 2004
Bilateral epidermoid cysts of the testis: Sonographic and MRI findings
Authors: Cittadini Giuseppe , Gauglio Cristina , Pretolesi Fabio , Santacroce Elena , Derchi Lorenzo E. 
Published: July 2004

AbstractEpidermoid cysts of the testis are rare benign lesions, without malignant potential, that can be managed conservatively with cyst enucleation and testis‐sparing surgery. Bilateral epidermoid cysts in the testes have been reported very infrequently. We report the sonographic and MRI findings in a patient who presented with a palpable nodule in only 1 testis, but in whom sonography showed bilateral lesions. On sonography, the cysts had an internal “onion‐ring” structure; color Doppler signals were absent. On MRI, the cysts had a laminated appearance, with alternating low‐ and high‐signal‐intensity areas on T2‐weighted images. These imaging findings and the negative results of laboratory tests for tumor markers suggested the correct diagnosis, and testis‐sparing surgery could be performed. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:370–372, 2004
Pleiotropic effects on mandibular morphology II: Differential epistasis and genetic variation in morphological integration
Authors: Cheverud James M. , Ehrich Thomas H. , Vaughn Ty T. , Koreishi Safina F. , Linsey Robin B. , Pletscher L. Susan 
Published: July 2004

AbstractThe evolution of morphological modularity through the sequestration of pleiotropy to sets of functionally and developmentally related traits requires genetic variation in the relationships between traits. Genetic variation in relationships between traits can result from differential epistasis, where epistatic relationships for pairs of loci are different for different traits. This study maps relationship quantitative trait loci (QTLs), specifically QTLs that affect the relationship between individual mandibular traits and mandible length, across the genome in an F2 intercross of the LG/J and SM/J inbred mouse strains (N = 1045). We discovered 23 relationship QTLs scattered throughout the genome. All mandibular traits were involved in one or more relationship QTL. When multiple traits were affected at a relationship QTL, the traits tended to come from a developmentally restricted region of the mandible, either the muscular processes or the alveolus. About one‐third of the relationship QTLs correspond to previously located trait QTLs affecting the same traits. These results comprise examples of genetic variation necessary for an evolutionary response to selection on the range of pleiotropic effects. J. Exp. Zool. (Mol. Dev. Evol.) 302B:000–000, 2004. © 2004 Wiley‐Liss, Inc.
Lovastatin modulation of microglial activation via suppression of functional CD40 expression
Authors: Townsend Kirk P. , Shytle Doug R. , Bai Yun , San Nan , Zeng Jin , Freeman Melissa , Mori Takashi , Fernandez Francisco , Morgan David , Sanberg Paul , Tan Jun 
Published: July 2004

AbstractRecent studies have shown that the 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase inhibitors (statins) possess antiinflammatory and immunomodulatory properties, distinct from their action of lowering serum lipid levels. Moreover, results of epidemiological studies suggest that long‐term use of statins is associated with a decreased risk for Alzheimer's disease (AD). Interestingly, lovastatin (one of the most commonly used anticholesterol drugs) treatment of vascular‐derived cells has been reported to antagonize activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway, and it is well known that the JAK/STAT pathway plays a central role in interferon‐γ (IFN‐γ)‐induced microglial CD40 expression. We and others have previously reported that microglial CD40 expression is significantly induced by IFN‐γ and amyloid‐β (Aβ) peptide. Moreover, it has been shown that CD40 signaling is critically involved in microglia‐related immune responses in the CNS. In this study, we examined the putative role of lovastatin in modulation of CD40 expression and its signaling in cultured microglia. RT‐PCR, Western immunoblotting, and flow cytometry data show that lovastatin suppresses IFN‐γ‐induced CD40 expression. Additionally, lovastatin markedly inhibits IFN‐γ‐induced phosphorylation of JAK/STAT1. Furthermore, lovastatin is able to suppress microglial tumor necrosis factor‐α, interleukin (IL)‐β1 and IL‐6 production promoted either by IFN‐γ or by Aβ peptide challenge in the presence of CD40 cross‐linking. To characterize further lovastatin's effect on microglial function, we examined microglial phagocytic capability following CD40 cross‐linking. Data reveal that lovastatin markedly attenuates CD40‐mediated inhibition of microglial phagocytosis of Aβ. These results provide an insight into the mechanism of the beneficial effects of lovastatin in neurodegenerative disorders, particularly Alzheimer's disease. © 2004 Wiley‐Liss, Inc.
Rapid analysis of triterpenic acids by liquid chromatography using porous graphitic carbon and evaporative light scattering detection
Authors: Bérangère Claude , Caussarieu Nathalie , Morin Philippe , Morin‐Allory Luc , Lafosse Michel 
Published: July 2004

AbstractAn original system which uses Porous Graphitic Carbon as support and a mixture of organic solvents as mobile phase is proposed for the analysis of triterpenic acids by liquid chromatography. The separation of betulinic acid, ursolic acid, oleanolic acid, and 18α‐ and 18β‐glycyrrhetinic acids was carried out within a short time and monitored by evaporative light scattering detection as universal detection method. Molecular modelling studies show that the main contribution to the selectivity comes from the electrostatic interaction characterised by the dipole moment of the products.
Mass spectrometric analysis of 1,2,4‐Oxadiazoles and 4,5‐Dihydro‐1,2,4‐Oxadiazoles
Authors: Srivastava Rajendra M. 
Published: July 2004

Abstract1,2,4‐Oxadiazoles and 4,5‐dihydro‐1,2,4‐oxadiazoles are an interesting class of compounds because of their pharmacological and other properties. Although short descriptions of these compounds under mass spectrometric conditions exist, we thought it worthwhile to write a comprehensive review of this class of compounds. Therefore, this revision deals first with 1,2,4‐oxadiazoles and then 4,5‐dihydro‐1,2,4‐oxadiazoles from 1964 until the year 2002. Much work on these compounds has been described under electron impact conditions and only a little under chemical ionization (CI). © 2004 Wiley Periodicals, Inc., Mass Spec Rev 24:328–346, 2005
Bacterial proteomics and its role in antibacterial drug discovery
Authors: Brötz‐Oesterhelt Heike , Bandow Julia Elisabeth , Labischinski Harald 
Published: July 2004

AbstractGene‐expression profiling technologies in general, and proteomic technologies in particular have proven extremely useful to study the physiological response of bacterial cells to various environmental stress conditions. Complex protein toolkits coordinated by sophisticated regulatory networks have evolved to accommodate bacterial survival under ever‐present stress conditions such as varying temperatures, nutrient availability, or antibiotics produced by other microorganisms that compete for habitat. In the last decades, application of man‐made antibacterial agents resulted in additional bacterial exposure to antibiotic stress. Whereas the targeted use of antibiotics has remarkably reduced human suffering from infectious diseases, the ever‐increasing emergence of bacteria that are resistant to antibiotics has led to an urgent need for novel antibiotic strategies. The intent of this review is to present an overview of the major achievements of proteomic approaches to study adaptation networks that are crucial for bacterial survival with a special emphasis on the stress induced by antibiotic treatment. A further focus will be the review of the, so far few, published efforts to exploit the knowledge derived from bacterial proteomic studies directly for the antibacterial drug‐discovery process. © 2004 Wiley Periodicals, Inc., Mass Spec Rev 24:549–565, 2005
Maternal chromatin remodeling during maturation and after fertilization in mouse oocytes
Authors: Spinaci Marcella , Seren Eraldo , Mattioli Mauro 
Published: July 2004

AbstractImmunofluorescence staining with antibodies against acetylated histone H4 and 5‐methylcytosine was carried out to investigate female chromatin remodeling throughout oocyte maturation and chromatin rearrangement involving both male and female genomes after fertilization. Oocyte cytoplasm remodels female chromatin in preparation of the fertilizing event and the subsequent chromatin rearrangement. Histone H4 are in fact progressively deacetylated whereas demethylating enzymes do not seem to be active over this period. The acetylase/deacetylase balance seems to be cell cycle dependent as female chromatin is deacetylated during maturation and reacetylated at telophase II stage both after fertilization and activation. On the contrary, DNA demethylation seems to be strictly selective. It is in fact confined to the remodeling of paternal genome after fertilization of mature oocytes as the ooplasm is not effective in demethylating either paternal chromatin in germinal vesicle breakdown (GVBD) fertilized oocytes or maternal genome of partenogenetically activated oocytes. Surprisingly, we induced maternal chromatin demethylation after fertilization by treating oocytes with a combination of a methyltransferase inhibitor, 5‐azacytidine (5‐AzaC), and a reversible and specific inhibitor of histone deacetylase, trichostatin A (TSA). This treatment likely induces a hyperacetylation of histones (thus favoring the access to demethylating enzymes by opening female chromatin structure) associated with a block of reparative methylation by inhibiting methytransferases. This manipulation of chromatin remodeling may have applications regarding the biological significance of aberrant DNA methylation. Mol. Reprod. Dev. 69: 215–221, 2004. © 2004 Wiley‐Liss, Inc.
Thyroglobulin type‐1 domain protease inhibitors exhibit specific expression in the cortical ooplasm of vitellogenic rainbow trout oocytes
Authors: Wood Antony W. , Matsumoto Jacqueline , Kraak Glen Van Der 
Published: July 2004

AbstractThe synthesis, uptake, and processing of yolk proteins remain poorly described aspects of oviparous reproductive development. In this study, we report the identification and characterization of two protease inhibitors in rainbow trout ovary whose expression and distribution are directly associated with yolk protein uptake in vitellogenic oocytes. The first transcript, termed “oocyte protease inhibitor‐1” (OPI‐1), is predicted to encode a 9.1 kDa, 87 amino acid protein containing a single thyroglobulin type‐1 (TY) domain, identifying it as a putative TY domain inhibitor. The second transcript, termed OPI‐2, is predicted to encode an 18.3 kDa, 173 amino acid protein with two similar, but not identical, TY domains. Messenger RNA expression of both genes was first detected in ovarian tissues at the onset of vitellogenesis, and persisted throughout the vitellogenic growth phase. We did not detect expression of either gene in previtellogenic ovaries, nor in any somatic tissues examined. Expression of OPI‐1 mRNA was significantly reduced in atretic follicles as compared to healthy vitellogenic follicles, suggesting a downregulation of inhibitor expression during oocyte atresia. Western immunoblot analyses of whole yolk from vitellogenic oocytes revealed the presence of two immunoreactive proteins that corresponded to the predicted sizes of OPI‐1 and OPI‐2. We detected strong crossreactivity of this antiserum with specific vesicles in the cortical ooplasm of vitellogenic oocytes, in regions directly associated with vitellogenin processing. The identification of OPI‐1 and OPI‐2 provides new evidence for the expression of multiple TY domain protease inhibitors likely involved in the regulation of yolk processing during oocyte growth in salmonids. Mol. Reprod. Dev. 69: 205–214, 2004. © 2004 Wiley‐Liss, Inc.