bluuebunny/crossref_metadata_2025_split huggingface dataset:
Harmonic‐free AC/DC rectifiers for HVDC systems
Authors: Villablanca Miguel E. , Rojas Felix E. 
Published: September 2009

AbstractThis paper presents an innovative method for reducing current distortion on the AC side of 12‐pulse series‐connected line‐commutated AC/DC rectifiers. Furthermore, the overlap conduction of thyristors is completely eliminated. The methodology involves an accurate shaping of the DC current by using two self‐commutated switches. This DC‐current shaping is reflected back into the shaping of the AC input currents, which become pure sine waves. Rectifying operation is possible with a simple control circuit, which is able to deal with both rapid load variations and failures in the self‐commutated switches. HVDC application of this innovative method is briefly examined, together with experimental results showing both the steady state and transient behavior of the technology by using a 380‐V 20‐kVA 50‐Hz laboratory prototype. Copyright © 2009 John Wiley & Sons, Ltd.
The novel adaptive sliding mode controller for synchronous reluctance motor speed drive
Authors: Chen Chien‐An , Chiang Huann‐Keng , Lin Bor‐Ren 
Published: September 2009

AbstractThis paper presents an adaptive sliding mode speed control design procedure for robust stabilization and disturbance rejection of the synchronous reluctance motor (SynRM) drive system. In general, the conventional sliding mode control design method is assumed that the upper boundary of parameter variations and external disturbances is known and the sign function is used. Therefore, it causes high frequency chattering and high gain phenomenon. In this paper, we proposed an adaptive sliding mode control of the SynRM speed drive system to avoid the above drawbacks. This method utilizes Lyapunov function candidate to guarantee the convergence and track the speed command of the SynRM drive system asymptotically. The estimator of parameter variations and external disturbances is designed to estimate the unknown uncertainty values in real‐time. This is different from conventional adaptive sliding mode control to estimate the unknown uncertainty upper boundary. Finally, we employ the experiments to validate the proposed method. Copyright © 2009 John Wiley & Sons, Ltd.
A Hermite finite element method for incompressible fluid flow
Authors: Holdeman J. T. 
Published: September 2009

AbstractWe describe some Hermite stream function and velocity finite elements and a divergence‐free finite element method for the computation of incompressible flow. Divergence‐free velocity bases defined on (but not limited to) rectangles are presented, which produce pointwise divergence‐free flow fields (∇·uh≡0). The discrete velocity satisfies a flow equation that does not involve pressure. The pressure can be recovered as a function of the velocity if needed. The method is formulated in primitive variables and applied to the stationary lid‐driven cavity and backward‐facing step test problems. Copyright © 2009 John Wiley & Sons, Ltd.
Multiple‐relaxation‐time lattice Boltzmann computation of channel flow past a square cylinder with an upstream control bi‐partition
Authors: Moussaoui M. A. , Jami M. , Mezrhab A. , Naji H. , Bouzidi M. 
Published: September 2009

AbstractThe present paper deals with the application of the multiple‐relaxation‐time lattice Boltzmann equation (MRT‐LBE) for the simulation of a channel flow with a bi‐partition located upstream of a square cylinder in order to control the flow. Numerical investigations have been carried out for different heights and positions of the bi‐partition at Reynolds number of 250. Key computational issues involved are the computation of fluid forces acting on the square cylinder, the vortex shedding frequency and the impact of such bluff body on the flow pattern. A particular attention is paid to drag and lift coefficients on the square cylinder. The predicted results from MRT‐LBE simulations show that in most cases, the interaction was beneficial insofar as the drag of the square block was lower with the bi‐partition than without it. Fluctuating side forces due to vortex shedding from the main body were also reduced for most bi‐partition positions. Copyright © 2009 John Wiley & Sons, Ltd.
Willingness‐to‐pay to avoid the time spent and discomfort associated with screening colonoscopy
Authors: Jonas Daniel E. , Russell Louise B. , Chou Jon , Pignone Michael 
Published: September 2009

AbstractBackground: The screening colonoscopy process requires a considerable amount of time and some discomfort for patients.Objective: We sought to use willingness‐to‐pay (WTP) to value the time required and the discomfort associated with screening colonoscopy. In addition, we aimed to explore some of the differences between and potential uses of the WTP and the human capital methods.Methods: Subjects completed a diary recording time and a questionnaire including WTP questions to value the time and discomfort associated with colonoscopy. We also valued the elapsed time reported in the diaries (but not the discomfort) using the human capital method.Results: 110 subjects completed the study. Mean WTP to avoid the time and discomfort was $263. Human capital values for elapsed time were greater. Linear regressions showed that WTP was influenced most by the difficulty of the preparation, which added $147 to WTP (p=0.03).Conclusions: WTP values to avoid the time and discomfort associated with the screening colonoscopy process were substantially lower than most of the human capital values for elapsed time alone. The human capital method may overestimate the value of time in situations that involve an irregular, episodic series of time intervals, such as preparation for or recovery after colonoscopy. Copyright © 2009 John Wiley & Sons, Ltd.
Workplace and organizational accident causation factors in the manufacturing industry
Authors: Katsakiori Panagiota , Kavvathas Aristomenis , Athanassiou George , Goutsos Stavros , Manatakis Emmanuel 
Published: September 2009

AbstractLabor inspectors investigate accidents to identify possible accident causes, initiate prosecution, and plan future accident prevention. The Method of Investigation for Labor Inspectors (MILI) was designed to help them to identify workplace and organizational factors in addition to immediate factors and legal breaches. The present study analyzes the impact of workplace (work design and provision of unsafe equipment) and organizational factors (training and employee involvement) on accident causation and validates MILI on real accident cases. Accident data from the manufacturing sector are analyzed with LISREL structural equation modeling. Results confirm the relationship between work design and training as well as between provision of unsafe equipment and employee involvement. The present study provides evidence that MILI is a structured accident investigation method allowing multiple accident causation factors to be revealed and that it could help all interested parts (not only labor inspectors, but companies as well) to thoroughly investigate occupational accidents. © 2009 Wiley Periodicals, Inc.
Identifying the age profile of patent citations: new estimates of knowledge diffusion
Authors: Mehta Aditi , Rysman Marc , Simcoe Tim 
Published: September 2009

AbstractPrevious research studies the age profile of patent citations to learn about knowledge flows over time. However, identification is problematic because of the collinearity between application year, citation year, and patent age. We show empirically that a patent's ‘citation clock’ does not start until it issues, and propose a highly flexible identification strategy that uses the lag between application and grant as a source of exogenous variation. We examine the potential bias if our assumptions are incorrect, and discuss extensions into other research areas. Finally, we use our method to re‐examine prior results on citation age profiles of patents from different technological fields and application year cohorts. Copyright © 2009 John Wiley & Sons, Ltd.
Why are gasoline prices sticky? A test of alternative models of price adjustment
Authors: Douglas Christopher , Herrera Ana María 
Published: September 2009

AbstractMacroeconomic models of business cycles rely on the assumption that firms adjust prices infrequently to generate the short‐run non‐neutrality of money documented by the monetary transmission literature. They posit different mechanisms to generate price stickiness, with correspondingly different implications for inflation dynamics. Using an autoregressive conditional binomial model, we test which mechanism is most consistent with the pattern of price adjustment found in daily wholesale gasoline price data. Our results lead us to reject menu costs and information‐processing delays but suggest that strategic considerations related to the idea of ‘fair pricing’ play an important role in accounting for price stickiness. Copyright © 2009 John Wiley & Sons, Ltd.
Nuclear matrix protein, prohibitin, was down‐regulated and translocated from nucleus to cytoplasm during the differentiation of osteosarcoma MG‐63 cells induced by ginsenoside Rg1, cinnamic acid, and tanshinone IIA (RCT)
Authors: Shi Song‐Lin , Li Qi‐Fu , Liu Qing‐Rong , Xu Dong‐Hui , Tang Jian , Liang Ying , Zhao Zhen‐Li , Yang Li‐Ming 
Published: September 2009

AbstractGinsenoside Rg1, cinnamic acid, and tanshinone IIA (RCT) are effective anticancer and antioxidant constituents of traditional Chinese herbal medicines of Ginseng, Xuanseng, and Danseng. The molecular mechanisms of anticancer effects of those constituents and their targets are unknown. Prohibitin, an inner membrane‐bound chaperone in mitochondrion involved in the regulation of cell growth, proliferation, differentiation, aging, and apoptosis, was chosen as a candidate molecular target because of its frequent up‐regulation in various cancer cells. We demonstrated that prohibitin existed in the filaments of the nuclear matrix of the MG‐63 cell and its expression was down‐regulated by the treatment of RCT using proteomic methodologies and Western blot analysis. Immunogold electro‐microscopy also found that prohibitin was localized on nuclear matrix intermediate filaments (NM‐IF) that had undergone restorational changes after RCT treatment. Prohibitin may function as a molecular chaperone that might interact with multiple oncogenes and tumor suppressor genes. We found that oncogenes c‐myc and c‐fos and tumor suppressor genes P53 and Rb were regulated by RCT as well and that these gene products co‐localized with prohibitin. Our study identified prohibitin as a molecular target of the effective anticancer constituents of Ginseng, Xuanseng, and Danseng that down‐regulated prohibitin in nuclear matrix, changed prohibtin trafficking from nucleolus to cytoplasm, and regulated several oncogenes and tumor suppressor genes. Prohibitin downregulation and cellular trafficking from nucleolus to cytoplasm indicated RCT protective roles in cancer prevention and treatment. J. Cell. Biochem. 108: 926–934, 2009. © 2009 Wiley‐Liss, Inc.
Oxidized low density lipoprotein decreases Rankl‐induced differentiation of osteoclasts by inhibition of Rankl signaling
Authors: Mazière Cécile , Louvet Loïc , Gomila Cathy , Kamel Said , Massy Ziad , Mazière Jean‐Claude 
Published: September 2009

AbstractThe role of OxLDL in the generation and progression of atherosclerosis is well admitted. In addition, it is well known that atherosclerosis is often accompanied by perturbations in bone remodeling, resulting in osteoporosis. In the current studies, the effect of Cu2+‐oxidized LDL (OxLDL) on RANKL‐induced RAW264.7 mouse monocytes‐macrophages differentiation to osteoclasts and on RANKL signaling pathway was investigated. OxLDL, within the range of 10–50 µg protein/ml, prevented RANKL‐induced generation of multinucleated osteoclast‐like cells and RANKL‐induced tartrate resistant acid phosphatase (TRAP) activity. OxLDL also prevented the RANKL‐induced phosphorylation of ERK, p38 and JNK kinases, together with the RANKL‐induced DNA binding activities of NFkappaB and NFAT transcription factors. Concomitantly, OxLDL enhanced RANKL‐induced generation of reactive oxygen species in a dose‐dependent manner. The antioxidant glutathione (GSH) prevented whereas the prooxidant compound buthionine‐sulfoximine (BSO) enhanced the effect of OxLDL on RANKL‐induced oxidative stress and RANKL‐induced differentiation. Finally, OxLDL also prevented RANKL‐induced TRAP activity and RANKL‐induced bone resorbing activity of human peripheral blood mononuclear cells. These results demonstrate that OxLDL, by generation of an intracellular oxidative stress, prevents the differentiation of osteoclasts by inhibition of RANKL signaling pathway. This might be related to the fact that atherosclerosis is accompanied by perturbations in bone and vascular remodeling, leading to osteoporosis and vascular calcification. J. Cell. Physiol. 221: 572–578, 2009. © 2009 Wiley‐Liss, Inc.
Rab22B is expressed in the CNS astroglia lineage and plays a role in epidermal growth factor receptor trafficking in A431 cells
Authors: Ng Ee Ling , Ng Jun Jie , Liang Fengyi , Tang Bor Luen 
Published: September 2009

AbstractThe expression profile and functions of the brain‐enriched Rab22B/Rab31 small GTPase had remained uncharacterized. Using specific antibodies against Rab22B, we found the protein to be exceptionally enriched in nestin and RC2‐positive radial glia of the embryonic mouse brain. In the adult brain, Rab22B is rather specifically expressed in glial fibrillary acidic protein (GFAP)‐positive mature astrocytes, but is not clearly detectable in either 2′,3′‐cyclic nucleotide 3′‐phosphodiesterase (CNPase)‐positive mature oligodendrocytes or βIII‐tubulin (TuJ)‐positive neurons. In probing for specific functions of Rab22B, we found that Rab22B silencing in A431 cells resulted in abnormal trafficking of the epidermal growth factor receptor (EGFR), Texas‐red‐labeled EGF, and the cation‐independent mannose 6‐phosphate receptor (M6PR). Affinity pull‐down assays and co‐immunoprecipitation analysis indicated that Rab22B could associate with EGFR in a GTP‐dependent manner. Rab22B is thus a Rab protein specifically expressed in the astroglia lineage and may have a role in regulating EGFR trafficking in some cell types. Given that EGFR signaling modulates astrocyte development and oncogenesis of multiple cell types, Rab22B may thus have specific developmental or pathophysiological roles in cell types which it is enriched in. J. Cell. Physiol. 221: 716–728, 2009. © 2009 Wiley‐Liss, Inc.
OPLA scaffold, collagen I, and horse serum induce a higher degree of myogenic differentiation of adult rat cardiac stem cells
Authors: Di Felice Valentina , Ardizzone Nella Maria , De Luca Angela , Marcianò Vito , Marino Gammazza Antonella , Macaluso Filippo , Manente Lucrezia , Cappello Francesco , De Luca Antonio , Zummo Giovanni 
Published: September 2009

AbstractIn the last few years, a major goal of cardiac research has been to drive stem cell differentiation to replace damaged myocardium. Several research groups have attempted to differentiate potential cardiac stem cells (CSCs) using bi‐ or three‐dimensional systems supplemented with growth factors or molecules acting as differentiating substances. We hypothesize that these systems failed to induce a complete differentiation because they lacked an architectural space. In the present study, we isolated a pool of small proliferating and fibroblast‐like cells from adult rat myocardium. The phenotype of these cells was assessed and the characterized cells were cultured in a collagen I/OPLA scaffold with horse serum to obtain fine myocardial differentiation. C‐KitPOS/Sca‐1POS CSCs fully differentiated in vitro when an environment more similar to the CSC niche was created. These experiments demonstrated an important model for the study of the biology of CSCs and the biochemical pathways that lead to myocardial differentiation. The results pave the way for a new surgical approach. J. Cell. Physiol. 221: 729–739, 2009. © 2009 Wiley‐Liss, Inc.
Molecular mechanisms mediating protective effect of cAMP on lipopolysaccharide (LPS)‐induced human lung microvascular endothelial cells (HLMVEC) hyperpermeability
Authors: Bogatcheva Natalia V. , Zemskova Marina A. , Kovalenkov Yevgeniy , Poirier Christophe , Verin Alexander D. 
Published: September 2009

AbstractUp to date, the nature of the sepsis‐induced vascular leakage is understood only partially, which limits pharmacological approaches for its management. Here we studied the protective effect of cAMP using endotoxin‐induced hyperpermeability as a model for barrier dysfunction observed in gram‐negative sepsis. We demonstrated that the alleviation of lipopolysaccharide (LPS)‐induced barrier compromise could be achieved by the specific activation of either protein kinase A (PKA) or Epac with cAMP analogs Bnz‐cAMP or O‐Me‐cAMP, respectively. We next studied the involvement of PKA substrates VASP and filamin1 in barrier maintenance and LPS‐induced barrier compromise. Depletion of both VASP and filamin1 with the specific siRNAs significantly exacerbated both the quiescent cells barrier and LPS‐induced barrier dysfunction, suggesting barrier‐protective role of these proteins. VASP depletion was associated with the more severe loss of ZO‐1 peripheral staining in response to LPS, whereas filamin1‐depleted cells reacted to LPS with more robust stress fiber induction and more profound changes in ZO‐1 and VE‐cadherin peripheral organization. Both VASP and filamin1 phosphorylation was significantly increased as a result of PKA activation. We next analyzed the effect of VASP and filamin1 depletion on the PKA‐dependent alleviation of LPS‐induced barrier compromise. We observed that Bnz‐cAMP ability to counteract LPS‐induced hyperpermeability was attenuated only by VASP, but not filamin1 depletion. Our data indicate that while PKA‐dependent VASP phosphorylation contributes to the protective effect of cAMP elicited on LPS‐compromised monolayers, filamin1 phosphorylation is unlikely to play a significant role in this process. J. Cell. Physiol. 221: 750–759, 2009. © 2009 Wiley‐Liss, Inc.
Osteoblast differentiation is functionally associated with decreased AMP kinase activity
Authors: Kasai Takayuki , Bandow Kenjiro , Suzuki Hiraku , Chiba Norika , Kakimoto Kyoko , Ohnishi Tomokazu , Kawamoto Shin‐ichiro , Nagaoka Eiichi , Matsuguchi Tetsuya 
Published: September 2009

AbstractOsteoblasts, originating from mesenchymal stem cells, play a pivotal role in bone formation and mineralization. Several transcription factors including runt‐related transcription factor 2 (Runx2) have been reported to be essential for osteoblast differentiation, whereas the cytoplasmic signal transduction pathways controlling the differentiation process have not been fully elucidated. AMP‐activated protein kinase (AMPK) is a serine–threonine kinase generally regarded as a key regulator of cellular energy homeostasis, polarity, and division. Recent lines of evidence have indicated that the activity of the catalytic α subunit of AMPK is regulated through its phosphorylation by upstream AMPK kinases (AMPKKs) including LKB1. Here, we explored the role of AMPK in osteoblast differentiation using in vitro culture models. Phosphorylation of AMPKα was significantly decreased during osteoblastic differentiation in both primary osteoblasts and MC3T3‐E1, a mouse osteoblastic cell line. Conversely, the terminal differentiation of primary osteoblasts and MC3T3‐E1 cells, represented by matrix mineralization, was significantly inhibited by glucose restriction and stimulation with metformin, both of which are known activators of AMPK. Matrix mineralization of MC3T3‐E1 cells was also inhibited by the forced expression of a constitutively active form of AMPKα. Metformin significantly inhibited gene expression of Runx2 along with osteoblast differentiation markers including osteocalcin (Ocn), bone sialo protein (Bsp), and osteopontin (Opn). Thus, our present data indicate that differentiation of osteoblasts is functionally associated with decreased AMPK activity. J. Cell. Physiol. 221: 740–749, 2009. © 2009 Wiley‐Liss, Inc.
Immunohistochemical characterization of TH13‐L2 spinal ganglia neurons in sheep (Ovis aries)
Authors: Russo Domenico , Clavenzani Paolo , Mazzoni Maurizio , Chiocchetti Roberto , Di Guardo Giovanni , Lalatta‐Costerbosa Giovanna 
Published: September 2009

AbstractSpinal ganglia (SG) neurons are commonly classified according to various specific features. The most widespread classification based on morphological and ultrastructural features subdivides SG neurons into light and small dark neurons. Using immunohistochemical, histochemical and lectin methods, it is possible to further subdivide the small dark neurons into two subpopulations: peptidergic and nonpeptidergic neurons. The majority of studies on SG neurons were carried out on mice and rats; there are few or no studies on large mammals. In this study, some of the widely used neuronal markers, neurofilament 200 kDa (NF200), substance P (SP), calcitonin gene‐related peptide (CGRP) and isolectin B4 (IB4), were employed to characterize neuronal nitric oxide synthase (nNOS)‐immunoreactivity (‐IR) in sheep (Ovis aries) SG (Th13‐L2) neurons. The majority of the SG neurons were IB4‐labeled (79 ± 10%), followed by NF200‐ (45 ± 4%), NOS‐ (44 ± 10%), SP‐ (42 ± 5%) and CGRP‐IR (35 ± 7%) neurons. The triple staining experiments showed that a higher percentage (75 ± 16%) of NOS‐IR neurons bound both IB4 and CGRP, or both IB4 and SP (49 ± 6%). The IB4 marker showed an unexpected staining pattern; in fact, IB4‐labeled neurons largely colocalized with NF200, usually considered a marker of light SG neurons, and with CGRP and SP. For this reason, IB4 cannot be employed in sheep to differentiate between light and dark neurons, or between peptidergic and nonpeptidergic neurons. These results suggest the importance of being cautious when comparing data among different species. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Time‐series investigation of fused vesicles in microvessel endothelial cells with atomic force microscopy
Authors: Chen Long , Chu Weiguo , Xu Yonggang , Chen Peipei , Lao Fang , Sun Quanmei , Feng Xizeng , Han Dong 
Published: September 2009

AbstractVesicles or caveolae within endothelial cells, fusing together to form vacuolar organelles, are implicated in macromolecular transport and cellular element transmigration across the blood–brain barrier (BBB) during inflammation and ischemia. Vacuolar organelles have been described by transmission electron microscopy and immunofluorescence, but the details of their dynamics have not been well addressed yet. Herein, by using tapping mode atomic force microscopy (AFM), we observed the time‐series changes of fused vesicles within the serum‐free cultured rat cerebral microvessel endothelial cells. The fused vesicles were certainly proved by fluorescent staining of Fm4‐64 combining simultaneous AFM imaging, as well as the field emission scanning electron microscopy technique. And energy dispersive spectrum results additionally implied that there may be specific structure and compositions around the vesicle region. These results indicate that increased vesicles in BBB may contribute to the formation of fused vesicles and a higher probability to construct the trans‐endothelial channel across endothelium layer. Furthermore, the AFM application may open up a new approach to investigate the details of transcellular process by fused vesicles. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.