bluuebunny/crossref_metadata_2025_split huggingface dataset:
Re‐ignition surge and high‐frequency arc extinction phenomena at 550‐kV shunt reactor current interruption
Authors: Okabe Shigemitsu , Koto Masanori , Koshizuka Tadashi , Shinkai Takeshi , Nishiwaki Susumu , Miyake Nobuyuki , Nakamoto Tetsuya , Saida Toshiyuki 
Published: October 2004

AbstractAt substations connected with transmission lines and cables, shunt reactors are sometimes installed to compensate the capacitive current of these lines and cables. It is known that re‐ignitions occur and high‐frequency currents flow during interruption of the shunt reactor currents by switches. When the high‐frequency currents are interrupted immediately after the re‐ignitions (which is called high‐frequency arc extinction), the result is often repetitive re‐ignitions or voltage escalations that produce dangerous overvoltages.The authors investigated the occurrence of high‐frequency arc extinctions in a 550‐kV one‐break SF6 gas circuit breaker during interruption of a 550‐kV shunt reactor current. Computations for a real 550‐kV substation gave a minimum frequency of 290 kHz for the high‐frequency current. However, 550‐kV reactor current interruption tests showed that high‐frequency arc extinctions did not occur even when this frequency was lowered to 26 kHz. Since high‐frequency arc extinction is generally likely to occur at lower frequencies, it was concluded that high‐frequency arc extinction will not occur in a 550‐kV one‐break SF6 gas circuit breaker during interruption of shunt reactor current in real substations. © 2001 Scripta Technica, Electr Eng Jpn, 136(2): 18–25, 2001
Wavelet matrix transform approach for electromagnetic scattering by a dielectric cylinder
Authors: Kigoshi Katsunori , Guan Ning , Yashiro Ichiro , Ohkawa Sumio 
Published: October 2004

AbstractThe wavelet matrix transform approach, in combination with the conventional method of moments, is used to solve the problem of electromagnetic scattering by a dielectric cylinder. First, the problem is formulated in terms of the integral equation for the field of a harmonic source in the presence of the cylinder. Then the equation is discretized to obtain a dense system of linear equations by dividing the cylinder into square cells which are small enough so that the field intensity is nearly uniform in each cell. Finally, the wavelet matrix transform is applied to produce a sparse system of linear equations which is treated effectively by a sparse linear system solver. © 2001 Scripta Technica, Electr Eng Jpn, 137(3): 1–9, 2001
A power factor correction with two‐input current mode using voltage doubler rectifier
Authors: Yamamoto Isamu , Matsui Keiju 
Published: October 2004

AbstractFor rectifier circuits with a small capacity, such as those for consumer electronics and appliances, capacitor input‐type rectifier circuits are generally used. Consequently, various harmonics generated within the power system become a serious problem. Various studies of this effect have been reported. However, most of these employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to overload, and brings low radio noise benefits. We propose a power factor correction scheme using a voltage doubler rectifier without switching devices. In this method, the input current is divided into two periods, where one period charges the small input capacitor and the other charges the large output capacitor. By dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be canceled between the two modes. Hence, the harmonic characteristics can be significantly improved, whereby the lower‐order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theoretical and experimental implementations. © 2001 Scripta Technica, Electr Eng Jpn, 137(3): 52–58, 2001
Cover Picture: Complex Formation of ICL670 and Related Ligands with FeIII and FeII (Eur. J. Inorg. Chem. 20/2004)
Authors: Steinhauser Stefan , Heinz Uwe , Bartholomä Mark , Weyhermüller Thomas , Nick Hanspeter , Hegetschweiler Kaspar 
Published: October 2004

AbstractThe cover picture shows the structure of the FeIII‐selective chelating agent ICL670 (R = COOH). ICL670 has a high potential for the oral treatment of iron overload, a condition that originates from regular blood transfusions, as are necessary in the treatment of β‐Thalassaemia. However, a possible problem arising from this treatment is the production of OH· radicals, which can be catalysed by redox‐cycling of labile FeII/FeIII species. For a conclusive consideration of potential oxidative stress, a careful elucidation of the stability and redox properties of the various FeII/FeIII species, which are present at physiological conditions, has been performed. Details are discussed in the article by K. Hegetschweiler et al. on p. 4177 ff.
Functional expression of V‐ATPases in the plasma membrane of glial cells
Authors: Philippe Jean‐Marc , Dubois Jean‐Marc , Rouzaire‐Dubois Beatrice , Cartron Pierre‐François , Vallette François , Morel Nicolas 
Published: October 2004

AbstractVacuolar H+ ATPase (V‐ATPase) activity is essential for many cellular processes, including intracellular membrane traffic, protein processing and degradation, and receptor‐mediated endocytosis. Proton transport by V‐ATPases could also play a role during cell transformation, tumorigenesis, and cell metastasis, and V‐ATPase c‐subunit overexpression was reported to be correlated with invasiveness of pancreatic tumors (Ohta et al., 1996). In the present work, we found that mRNAs encoding V‐ATPase subunits are not overexpressed in C6 tumoral glioma cells when compared with immortalized astrocytes DI TNC1 and astrocytes in primary cultures. Accordingly, V‐ATPase subunit mRNA levels are similar in human gliomas (grade II or IV) and in peritumoral tissues. A significant proportion (25%) of V‐ATPase is present in the plasma membrane of both the C6 and the DI TNC1 astrocytic cells in culture. A bafilomycin‐sensitive hyperpolarizing pump current through the plasma membrane was detected and measured after ionic channel inhibition, which corresponds most probably to an electrogenic transport of protons. This suggests that the plasma membrane V‐ATPase is active. It could contribute to cytoplasmic pH regulation in astrocytic cells. GLIA 37:365–373, 2002. © 2002 Wiley‐Liss, Inc.
Identification of growth factors that promote long‐term proliferation of olfactory ensheathing cells and modulate their antigenic phenotype
Authors: Alexander Claire L. , Fitzgerald Una F. , Barnett Susan C. 
Published: October 2004

AbstractOlfactory ensheathing cells can develop into distinct subtypes in culture after incubation in serum‐free medium conditioned by astrocytes, which have Schwann cell–like and astrocyte‐like properties. It has not been possible so far to modulate and grow large numbers of these olfactory ensheathing cell subtypes. In this study, we have shown that astrocyte‐conditioned medium, although promoting differentiation of the two olfactory ensheathing cell types, is growth‐restrictive after 14 days, probably due to the upregulation of p16 and p27. Growth arrest can be overridden and cells maintained for a further 11 weeks, by a mitogen mix of fibroblast growth factor 2, forskolin, and heregulin (olfactory mitogen medium) combined with astrocyte‐conditioned medium. In the absence of astrocyte‐conditioned medium, combinations of the same factors can also override growth arrest but to a lesser extent. Olfactory mitogen medium combined with astrocyte‐conditioned medium upregulates O4 and low‐affinity nerve growth factor receptor expression on olfactory ensheathing cells, leading to a 100% Schwann cell–like phenotype. If cells are maintained in olfactory mitogen medium alone, or if they are treated with forskolin or fibroblast growth factor 2 diluted in serum‐free medium, O4 and low‐affinity nerve growth factor receptor expression remains at 100%, but there is also an increase in expression of E‐NCAM, the astrocyte‐like marker. Medium containing serum also overrides growth arrest, but for only 4 weeks, during which time most differentiation‐specific markers disappear. These studies have allowed us to define conditions to modulate the olfactory ensheathing cell phenotype. GLIA 37:349–364, 2002. © 2002 Wiley‐Liss, Inc.
Mts1 protein expression in the central nervous system after injury
Authors: Kozlova Elena N. , Lukanidin Eugene 
Published: October 2004

AbstractWe recently showed that Mts1 is expressed in white matter astrocytes in the rat brain and spinal cord from the first postnatal day. Its expression level declined in the adult CNS, but its topographical localization was maintained. Only white matter astrocytes in the cerebellum did not express Mts1. After dorsal root or sciatic nerve injury, we observed a marked upregulation of Mts1 in the area of the dorsal funiculus undergoing Wallerian degeneration. Here we show that upregulation of Mts1 is a consistent feature of astrocytes in white matter undergoing Wallerian degeneration. In addition, Mts1 is upregulated in astrocytes outlining the lesion site of a penetrating injury to the forebrain, or cerebellum. Gray matter astrocytes did not express Mts1, even after direct injury. In injured brain, we consistently noted a close relationship between Mts1‐expressing astrocytes and ED1‐positive microglia/macrophages, which are known to be highly motile cells. Mts1 was expressed in the periventricular area and the rostral migratory stream, i.e., sites of ongoing neuroplasticity in adulthood, and was upregulated in these areas after injury. These data suggest that Mts1‐expressing astrocytes play a significant role in degenerative events in the mature white matter, interact with phagocytic microglia/macrophages and regulate cell migration and differentiation in areas of the adult brain with a high degree of plasticity. GLIA 37:337–348, 2002. © 2002 Wiley‐Liss, Inc.
CNTF and CNTF receptor alpha are constitutively expressed by astrocytes in the mouse brain
Authors: Dallner Christine , Woods Alisa G. , Deller Thomas , Kirsch Matthias , Hofmann Hans‐Dieter 
Published: October 2004

AbstractCiliary neurotrophic factor (CNTF) is regarded as one of the signals that lead to astrocyte activation following central nervous system lesion. However, it is not clear if CNTF can directly initiate astrocytic responses to injury because CNTF levels are very low in most areas of the unlesioned brain and CNTF receptor (CNTFRα) expression by astrocytes has not yet been demonstrated in the intact brain. In the present study, the expression patterns of CNTF protein and CNTFRα mRNA were studied in the intact mouse brain using immunocytochemistry and in situ hybridization, respectively. These procedures were combined with immunocytochemistry for glial fibrillary acidic protein in order to identify CNTF‐ and CNTFRα‐expressing astrocytes. CNTF‐immunoreactive astrocytes were exclusively found in white matter structures such as the optical tract, the corticospinal tract, and the fimbria‐fornix. Gray matter astrocytes did not exhibit CNTF immunoreactivity. In contrast, CNTFRα mRNA‐expressing astrocytes were found in gray matter areas, preferentially in the molecular layers of the cortex and hippocampus. White matter astrocytes did not show a detectable CNTFRα mRNA signal. These data demonstrate that both CNTF and its receptor are constitutively expressed by astrocytes in mouse brain. The nonoverlapping locations of astrocytes expressing detectable levels of CNTF and CNTFRα, respectively, may be related to distinct postlesional functions of these two glial cell populations. GLIA 37:374–378, 2002. © 2002 Wiley‐Liss, Inc.
Astrocyte‐derived factors modulate the inhibitory effect of ethanol on dendritic development
Authors: Yanni Penelope A. , Rising Lisa J. , Ingraham Christine A. , Lindsley Tara A. 
Published: October 2004

AbstractNumerous studies in vivo and in vitro have demonstrated that ethanol disrupts neuromorphogenesis. However, it has not been determined what role, if any, is played by non‐neuronal cells in mediating this effect. We recently reported that ethanol inhibits dendritic development in low‐density cultures of fetal rat hippocampal pyramidal neurons (Yanni and Lindsley, 2000: Dev Brain Res 120:233–243). In this culture system, cortical astrocytes precondition neuronal culture media for 2 days before the addition of neurons, which then develop on a separate substrate in coculture with the astrocytes. To determine whether astrocyte response to ethanol mediates the effects of ethanol on neurons, the present study compared dendritic development of neurons after 6 days in medium containing 400 mg/dl ethanol in coculture with live astrocytes and in conditioned medium from astrocytes that were never exposed to ethanol. The same experiment was also performed with and without ethanol present during astrocyte preconditioning of the medium. The effects of ethanol differed depending on when it was added to the cultures relative to addition of newly dissociated neurons. However, the effects of ethanol were not related to whether neurons were cocultured with live astrocytes. When astrocytes preconditioned the medium normally, ethanol added at plating inhibited dendritic development of neurons regardless of whether they were maintained in coculture with live astrocytes or in conditioned medium. In surprising contrast, the presence of ethanol during astrocyte preconditioning of the media had a growth promoting effect on subsequent dendrite development despite the continued presence of ethanol in the medium. Thus, astrocytes release soluble factors in response to ethanol that can protect neurons from the inhibitory effects of ethanol on dendritic growth, but the timing of neuronal exposure to these factors, or their concentration, may influence their activity. GLIA 38:292–302, 2002. © 2002 Wiley‐Liss, Inc.
Areas of brain activation in males and females during viewing of erotic film excerpts
Authors: Karama Sherif , Lecours André Roch , Leroux Jean‐Maxime , Bourgouin Pierre , Beaudoin Gilles , Joubert Sven , Beauregard Mario 
Published: October 2004

AbstractVarious lines of evidence indicate that men generally experience greater sexual arousal (SA) to erotic stimuli than women. Yet, little is known regarding the neurobiological processes underlying such a gender difference. To investigate this issue, functional magnetic resonance imaging was used to compare the neural correlates of SA in 20 male and 20 female subjects. Brain activity was measured while male and female subjects were viewing erotic film excerpts. Results showed that the level of perceived SA was significantly higher in male than in female subjects. When compared to viewing emotionally neutral film excerpts, viewing erotic film excerpts was associated, for both genders, with bilateral blood oxygen level dependant (BOLD) signal increases in the anterior cingulate, medial prefrontal, orbitofrontal, insular, and occipitotemporal cortices, as well as in the amygdala and the ventral striatum. Only for the group of male subjects was there evidence of a significant activation of the thalamus and hypothalamus, a sexually dimorphic area of the brain known to play a pivotal role in physiological arousal and sexual behavior. When directly compared between genders, hypothalamic activation was found to be significantly greater in male subjects. Furthermore, for male subjects only, the magnitude of hypothalamic activation was positively correlated with reported levels of SA. These findings reveal the existence of similarities and dissimilarities in the way the brain of both genders responds to erotic stimuli. They further suggest that the greater SA generally experienced by men, when viewing erotica, may be related to the functional gender difference found here with respect to the hypothalamus. Hum. Brain Mapping 16:1–13, 2002. © 2002 Wiley‐Liss, Inc.
Monte Carlo simulation studies of EEG and MEG localization accuracy
Authors: Liu Arthur K. , Dale Anders M. , Belliveau John W. 
Published: October 2004

AbstractBoth electroencephalography (EEG) and magnetoencephalography (MEG) are currently used to localize brain activity. The accuracy of source localization depends on numerous factors, including the specific inverse approach and source model, fundamental differences in EEG and MEG data, and the accuracy of the volume conductor model of the head (i.e., the forward model). Using Monte Carlo simulations, this study removes the effect of forward model errors and theoretically compares the use of EEG alone, MEG alone, and combined EEG/MEG data sets for source localization. Here, we use a linear estimation inverse approach with a distributed source model and a realistic forward head model. We evaluated its accuracy using the crosstalk and point spread metrics. The crosstalk metric for a specified location on the cortex describes the amount of activity incorrectly localized onto that location from other locations. The point spread metric provides the complementary measure: for that same location, the point spread describes the mis‐localization of activity from that specified location to other locations in the brain. We also propose and examine the utility of a “noise sensitivity normalized” inverse operator. Given our particular forward and inverse models, our results show that 1) surprisingly, EEG localization is more accurate than MEG localization for the same number of sensors averaged over many source locations and orientations; 2) as expected, combining EEG with MEG produces the best accuracy for the same total number of sensors; 3) the noise sensitivity normalized inverse operator improves the spatial resolution relative to the standard linear estimation operator; and 4) use of an a priori fMRI constraint universally reduces both crosstalk and point spread. Hum. Brain Mapping 16:47–62, 2002. © 2002 Wiley‐Liss, Inc.
Necrotizing fasciitis of the head and neck: A report of two patients and review
Authors: Chattar‐Cora Deowall , Tulsyan Nirman , Cudjoe Ernest A. , Onime Godfrey D. , Pyo Daniel J. , Weinstein Larry 
Published: October 2004

AbstractBackgroundNecrotizing fasciitis is a disfiguring condition that can be fatal. The head and neck region is rarely affected. However, when involved, the functional and cosmetic sequelae can be considerable.Materials and MethodsWe present two case histories, discuss salient diagnostic points, treatment, and review published data on this topic.ResultsWith a timely diagnosis we were able to diagnose and appropriately treat these patients.ConclusionsNecrotizing fasciitis is a disfiguring condition that can be fatal if not diagnosed in a timely fashion. Diagnosis and treatment require a high index of suspicion, immediate operative intervention, broad‐spectrum antibiotics, and appropriate supportive care. © 2002 Wiley Periodicals, Inc.
Role of Epstein‐Barr virus and cytomegalovirus in the etiology of benign parotid tumors
Authors: Laane Christina J. , Murr Andrew H. , Mhatre Anand N. , Jones Kirk D. , Lalwani Anil K. 
Published: October 2004

AbstractBackgroundPleomorphic adenomas and Warthin's tumors are the two most common benign parotid tumors. Previous studies investigating the role of viruses in tumorigenesis of these neoplasms have been conflicting. The aim of this study was to determine whether Epstein‐Barr virus (EBV) or cytomegalovirus (CMV) might play a role in the pathogenesis of pleomorphic adenomas and Warthin's tumors.MethodsParaffin‐embedded surgical specimens of 24 pleomorphic adenomas, 10 Warthin's tumors, and 13 normal parotid tissues were obtained from the University of California–San Francisco Pathology Department. Genomic DNA was extracted from the specimens, and primers for connexin 26, a gap junction protein, were used to confirm the integrity of this DNA. The presence or absence of EBV and CMV DNA within the samples was determined with PCR‐based assays, in which radiolabeled primers were used for maximal sensitivity of detection.ResultsPCR analysis of serially diluted control DNA revealed that using radiolabeled primers, five copies of viral DNA could be detected. By use of this method, we showed that none of the 24 pleomorphic adenomas, 10 Warthin's tumors, or 13 normal parotid samples contained EBV DNA or CMV DNA.Conclusions. These results do not support CMV or EBV as etiologic factors in pleomorphic adenomas or Warthin's tumors. In addition, normal parotid seems not to harbor either of these viruses. Future studies with larger numbers of specimens are needed to confirm these findings. © 2002 Wiley Periodicals, Inc.
Functional assessment using Constant's Shoulder Scale after modified radical and selective neck dissection
Authors: Chepeha Douglas B. , Taylor Rodney J. , Chepeha Judith C. , Teknos Theodoros N. , Bradford Carol R. , Sharma Pramod K. , Terrell Jeffrey E. , Wolf Gregory T. 
Published: October 2004

AbstractBackgroundConstant's Shoulder Scale is a validated and widely applied instrument for assessment of shoulder function. We used this instrument to assess which treatment and demographic variables contribute to shoulder dysfunction after neck dissection in head and neck cancer patients.MethodsA convenience sample of 54 patients with 64 neck dissections and minimum follow‐up of 11 months were evaluated. Thirty‐two accessory nerve–sparing modified radical (MRND) and 32 selective neck (SND) dissections were performed. Multivariable regression analysis was used to determine the variables that were predictive for shoulder dysfunction. Clinical variables included age, time from surgery, handedness, weight, radiation therapy, neck dissection type, tumor stage, and site.ResultsPatients receiving MRND had significantly worse shoulder function than patients with SND (p = .0007). Radiation therapy contributed negatively, whereas weight contributed positively (p = .0001).ConclusionsThe critical factors contributing to shoulder dysfunction after neck dissection were weight, radiation therapy, and neck dissection type. © 2002 Wiley Periodicals, Inc.
Prognostic factors in head and neck rhabdomyosarcoma
Authors: Simon James H. , Paulino Arnold C. , Smith Russell B. , Buatti John M 
Published: October 2004

AbstractBackgroundRhabdomyosarcoma comprises less than 1% of all head and neck cancer. The purpose of our study is to review our institutional experience in this disease and to identify possible prognostic factors for patients with head and neck rhabdomyosarcoma.MethodsOne hundred forty patients with rhabdomyosarcoma were identified from 1955–1999 within the tumor registry. Of these cases, 49 (35%) were noted to be primary head and neck rhabdomyosarcomas. Retrospective chart reviews were completed to obtain the following data: age, gender, site, tumor size, histologic findings, Intergroup Rhabdomyosarcoma Study Group, treatment, local control, and survival.ResultsThe 5‐year overall survival and local control rates were 60% ± 14% and 70% ± 14%, respectively. Tumor size ≤5 cm (p = .014) and age ≤11 years (p = .036) were predictive of improved survival, whereas age ≤11 years was predictive of improved local control (p = .006). Children ≤11 years with a≤5‐cm tumor have the best overall survival, whereas patients >11 years with a tumor >5 cm have the worst survival. The 5‐year survival was intermediate for children ≤11 years with a >5‐cm tumor and patients >11 years with a ≤5‐cm tumor. Radiotherapy treatment duration ≤45 days in group III disease was associated with improved overall survival but not local control. For the six patients with group I or II disease, who did not receive initial chemotherapy, five had relapses at the primary and/or distant sites.ConclusionsImprovement in outcome was obtained with multimodality treatment regimens for head and neck rhabdomyosarcoma. Both tumor size and age of patient were found to influence survival. © 2002 Wiley Periodicals, Inc.