bluuebunny/crossref_metadata_2025_split huggingface dataset:
The QuantumCor device for treating mitral regurgitation: An animal study
Authors: Goel Ramil , Witzel Thomas , Dickens Duane , Takeda Patricia A. , Heuser Richard R. 
Published: May 2009

AbstractObjectives: The mitral annular contraction achieved could help reduce mitral regurgitation (MR), and with appropriate modifications, be applied to human subjects providing a potentially effective percutaneous method of valve repair. Background: MR is an important source of morbidity and is an independent predictor of mortality. A variety of percutaneous approaches are being developed to address this issue. We introduce a novel potential method utilizing radiofrequency (RF) energy to heat and shrink the mitral valve annulus in an animal model. Methods: In open‐heart procedures in 16 healthy sheep (six with naturally occurring MR), we used a malleable probe (QuantumCor, Lake Forest, CA) that conforms to the annular shape to deliver RF energy via a standard generator to replicate a surgical mitral annular ring. Seven sheep were followed chronically and their mitral annulus dimensions measured serially. Results: All sheep underwent intracardiac echocardiography or direct circumferential measurement of the mitral annulus before and after RF therapy. RF therapy was administered in less than 4 min in each case, and the mean anteroposterior (AP) annular distance was reduced by a mean of 23.8% (AP diameter reduction 5.75 ± 0.86 mm, P < 0.001) acutely. In the six sheep with nonischemic MR, regurgitation was eliminated. Acute histopathology (HP) demonstrated no damage to the leaflets, coronary sinuses, or coronary arteries. At the end of the intended 6‐month period of the chronic part of the study, four of the seven animals survived. The four treatment animals showed significant reductions in mitral A‐P dimension, with a percent diameter reduction of 26.4% (AP diameter reduction 7 ± 2.3 mm). Conclusion: The application of RF directly to heat the mitral annulus has resulted in sustained contraction of the annulus in this limited preclinical animal study. With further study and possible modifications, it holds promise for future application in human subjects with MR. © 2009 Wiley‐Liss, Inc.
A new generalized high‐frequency voltage injection method and mirror‐phase estimation method for sensorless drive of salient‐pole PMSMSs
Authors: Shinnaka Shinji 
Published: May 2009

AbstractThis paper proposes a new generalized high‐frequency voltage injection method for sensorless drive of salient‐pole permanent‐magnet synchronous motors. The injected high‐frequency voltage has a unique spatially‐rotating elliptical shape, with the amplitudes of both the major and minor axes varying with the motor speed, and can be designed by selecting a design parameter. The high‐frequency current caused by the injected voltage, which has information on the rotor phase to be estimated, is speed‐independent, that is, is not affected by the motor speed at all. Consequently, the rotor phase can be estimated in a wide speed range from zero to the rated speed. By selection of the design parameter, the properties of the high‐frequency current can be adjusted appropriately to the associated motor‐drive system consisting of a motor and an inverter. As a versatile phase estimation method for estimating rotor phase using the high‐frequency current, the “mirror‐phase estimation method” is reconstructed and reproposed. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(3): 67–82, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20803
Three‐dimensional tree simulation utilizing a three‐layer model
Authors: Uehara Hiroaki , Kudo Katsutoshi 
Published: May 2009

AbstractRecently, polymer/polymer composite insulating systems have been widely used in high‐voltage equipment and power cables. Such composite insulating systems always have an interface between two polymeric insulating materials. This interface may cause partial discharge and electrical treeing under high electric stresses. The electrical properties of this polymer/polymer interface have not yet been fully understood. It has been shown that the propagation characteristics of electrical trees in polymer/polymer composite insulating materials considerably vary depending on the combination of polymers. It has also been shown that a cavity or a thin gas layer generates near the polymer barrier molded in the base polymer, by the pressure of decomposing gas occurring in the tree channels during AC tree extension.In this study, we will investigate the three‐dimensional simulated tree utilizing a three‐layer model considering a thin gas layer on a barrier based on a DBM model with growth probability.The results show that the critical fields of air layer are related to the easiness of tree propagation in the air layer. Moreover, it is suggested that the three‐layer model is more effective than the two‐layer model when the tree propagation is discussed in detail. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(3): 1–9, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20808
Cooperative operation of a wind energy conversion system with a hydrogen electrolyzer by using an adjustable speed flywheel generator
Authors: Nobuta Masaaki , Takahashi Rion , Murata Toshiaki , Tamura Junji , Sugimasa Masatoshi , Komura Akiyoshi , Futami Motoo , Ichinose Masaya , Ide Kazumasa 
Published: May 2009

AbstractHydrogen is considered as the energy source of the next generation. This paper proposes a system which consists of Flywheel Generator (FWG), Wind Energy Conversion System (WECS), and Hydrogen Electrolyzer (HE), for the purpose of hydrogen generation and grid output power smoothing. The cooperative control among flywheel generator, hydrogen electrolyzer, and wind generator is performed by controlling the flywheel generator. Simulations have been done by PSCAD/EMTDC. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(3): 19–27, 2009; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/eej.20863
QM/MM calculation of solvent effects on absorption spectra of guanine
Authors: Parac Maja , Doerr Markus , Marian Christel M. , Thiel Walter 
Published: May 2009

AbstractElectronic spectra of guanine in the gas phase and in water were studied by quantum mechanical/molecular mechanical (QM/MM) methods. Geometries for the excited‐state calculations were extracted from ground‐state molecular dynamics (MD) simulations using the self‐consistent‐charge density functional tight binding (SCC‐DFTB) method for the QM region and the TIP3P force field for the water environment. Theoretical absorption spectra were generated from excitation energies and oscillator strengths calculated for 50 to 500 MD snapshots of guanine in the gas phase (QM) and in solution (QM/MM). The excited‐state calculations used time‐dependent density functional theory (TDDFT) and the DFT‐based multireference configuration interaction (DFT/MRCI) method of Grimme and Waletzke, in combination with two basis sets. Our investigation covered keto‐N7H and keto‐N9H guanine, with particular focus on solvent effects in the low‐energy spectrum of the keto‐N9H tautomer. When compared with the vertical excitation energies of gas‐phase guanine at the optimized DFT (B3LYP/TZVP) geometry, the maxima in the computed solution spectra are shifted by several tenths of an eV. Three effects contribute: the use of SCC‐DFTB‐based rather than B3LYP‐based geometries in the MD snapshots (red shift of ca. 0.1 eV), explicit inclusion of nuclear motion through the MD snapshots (red shift of ca. 0.1 eV), and intrinsic solvent effects (differences in the absorption maxima in the computed gas‐phase and solution spectra, typically ca. 0.1–0.3 eV). A detailed analysis of the results indicates that the intrinsic solvent effects arise both from solvent‐induced structural changes and from electrostatic solute–solvent interactions, the latter being dominant. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
Can DFT methods correctly and efficiently predict the coordination number of copper(I) complexes? A case study
Authors: Ansbacher Tamar , Srivastava Hemant Kumar , Martin Jan M. L. , Shurki Avital 
Published: May 2009

AbstractThe coordination number of various experimentally known Cu(I) compounds is studied using density functional theory. Various basis sets are tested, aiming to establish a reliable level for prediction of the coordination number of these and other Cu(I) complexes. It is found that most levels exhibit correct trends, namely, the bulkier ligands demonstrate larger preference for coordination of two ligands. Proper absolute values are obtained when dispersion corrections are also included in the calculations. It is concluded that the fairly small modified 6‐31+G* basis set due to Pulay represents a good compromise between accuracy and efficiency, followed by Balabanov and Peterson's all‐electron aug‐cc‐pVDZ basis set. The overall energy is decomposed into various components whose relative contribution to the overall tendency of forming a complex with a particular coordination is examined. It is shown that two opposing contributions play a major role: the interaction energy of the ligand being added and the deformation energy of the copper's coordination sphere prior to the ligand addition. The former being a stabilizing contribution, leads to higher coordination numbers while the later, a destabilizing contribution, is shown to favor lower coordination numbers. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
Episodic coastal dune development in the Taean Peninsula and Anmyeon Island, Korea, during the mid to late Holocene
Authors: Yu Keun Bae , Brook George A. , Rhew Hosahng , Shin Young Ho , Kim Sung Hwan , Brook Fong Z. 
Published: May 2009

AbstractThe episodic nature of coastal dune development has been widely identified in many dune areas over the world. What causes such episodicity is still hotly debated. Sea‐level change, climatic change and human impact have widely been reported as the main forcings, though there is no agreement yet upon which factors are critical. This research provides some evidence that sea‐level fluctuation and climatic factors controlled the episodic dune building together, based upon optically stimulated luminescence (OSL) dune ages on the west coast of Korea. The newly obtained and published OSL dune ages on the west coast of the Taean Peninsula and Anmyeon Island, Korea, indicate the six main periods of dune building: 5.5, 4.3, 1.5, 1.3, 1.1 and 0.7 ka. They correlate with evidence of colder climate in East Asia that imply stronger dune‐forming winds during the winter under the influence of a more intense Siberian High. They also correlate with periods of higher sea level over the present one with fluctuations. Thus, episodic dune activity along the west coast of the Korean Peninsula during the mid to late Holocene appears to be linked to stronger winter winds capable of moving sand from the beach to the foredune ridges with short‐term fluctuations during the high stands. Copyright © 2009 John Wiley & Sons, Ltd.
Attachment orientations in business‐to‐business relationships
Authors: Paulssen Marcel 
Published: May 2009

AbstractAttachment theory has produced an impressive body of evidence for explaining individual differences in personal relationship behavior. The current study examines whether attachment theory can be fruitfully extended to business‐to‐business relationships. Hypotheses about the impact of personal attachment orientations on key relationship constructs are developed and empirically tested in two business‐to‐business relationships. Customers who are securely attached in their personal relationships with their romantic partners experience higher levels of satisfaction, trust, and repurchase intent in their business‐to‐business relationships. In addition, an attachment scale that is specifically tailored for a business‐to‐business context is developed. Two dimensions of business attachment are empirically derived: secure business attachment measures the ability and willingness to rely on the business partner, and close business attachment measures the desire to develop personal bonds with a business partner or its employees. The two business attachment dimensions can be used to segment customers with respect to their intrinsic retainability and their preference for personal bonding with their business partners. © 2009 Wiley Periodicals, Inc.
Long‐term effects of pallidal or subthalamic deep brain stimulation on quality of life in Parkinson's disease
Authors: Volkmann Jens , Albanese Alberto , Kulisevsky Jaime , Tornqvist Aana‐Lena , Houeto Jean‐Luc , Pidoux Bernard , Bonnet Anne‐Marie , Mendes Alexandre , Benabid Alim‐Louis , Fraix Valerie , Van Blercom Nadege , Xie Jing , Obeso José , Rodriguez‐Oroz Maria Cruz , Guridi Jurge , Schnitzler Alfons , Timmermann Lars , Gironell Alexandre A. , Molet Juan , Pascual‐Sedano Benta , Rehncrona Stig , Moro Elena , Lang Anthony C. , Lozano Andres M. , Bentivoglio Anna Rita , Scerrati Massimo , Contarino Maria Fiorella , Romito Luigi , Janssens Marc , Agid Yves 
Published: May 2009

AbstractWe assessed the effects of deep brain stimulation of the subthalamic nucleus (STN‐DBS) or internal pallidum (GPi‐DBS) on health‐related quality of life (HrQoL) in patients with advanced Parkinson's disease participating in a previously reported multicenter trial. Sickness Impact Profile (SIP) questionnaires were available for analysis in a subgroup of n = 20/20 patients with GPi‐DBS and n = 45/49 patients with STN‐DBS at baseline, 6 and 36 months. The SIP provides a physical dimension and a psychosocial dimension sum score and 12 category scores: Alertness/Intellectual Behavior (AIB), Ambulation (A), Body Care and Movement (BCM), Communication (C), Eating (E), Emotional Behavior (EB), Home Management (HM), Mobility (M), Recreation and Pastimes (RP), Sleep and Rest (SR), Social Interaction (SI), and Work (W). Motor functioning was assessed by means of the Unified Parkinson's Disease Rating Scale and diaries. At 6 months significant improvements in off‐period motor symptoms and activities of daily living were paralleled by significant reductions in the total, physical, and psychosocial SIP score in both treatment groups. At 3 years, sustained improvements were observed in the physical dimension score, BCM, E, M, RP after STN‐DBS and M, SI after GPi‐DBS. All other SIP subscores approached baseline values, but were still the same or better (except C) whereas motor functioning remained stable after 36 months. STN‐DBS and GPi‐DBS led to significant early improvements in HrQoL. Despite sustained motor improvements many of these initial benefits were lost after 3 years. This may reflect either progression of the disease or adaptive changes in the subjective perception of health‐related wellbeing over time. © 2009 Movement Disorder Society
Recurrent acute dystonic reaction and oculogyric crisis despite withdrawal of dopamine receptor blocking drugs
Authors: Schneider Susanne A. , Udani Vrajesh , Sankhla Charulata Sawant , Bhatia Kailash P. 
Published: May 2009

AbstractAdverse events of dopamine‐blocking agents include acute dystonic reactions and oculogyric crises (OGCs). OGCs may be recurrent on maintenance of or re‐exposure to the drug. Thus, complete withdrawal is recommended. Recurrent episodes of acute dystonia despite withdrawal and the lack of further exposure to antidopaminergic agents are usually not seen. Here, we report three cases with recurrent OGCs despite complete withdrawal of neuroleptics. Triggering or priming factors were a single dose of haloperidol in two cases and a single dose of metoclopramide in one case. Episodes reoccurred spontaneously, but responded to anticholinergics. The pathomechanisms of acute dystonic reactions and OGCs remain unclear. Parallels to levodopa‐induced dyskinesias in Parkinson's disease, as well as to dopa‐responsive dystonia, paroxysmal dyskinesias, and channelopathies are discussed here. Whether there is a genetic susceptibility or some other reason for only some patients developing this phenomenon remains unclear. © 2009 Movement Disorder Society
Effect of movement frequency on repetitive finger movements in patients with Parkinson's disease
Authors: Stegemöller Elizabeth L. , Simuni Tanya , MacKinnon Colum 
Published: May 2009

AbstractPerformance of repetitive hand movements in patients with Parkinson's disease (PD) is characterized by slowness, reduced movement amplitude, and hesitation or arrests in ongoing movement. Currently, the factors and mechanisms contributing to impaired performance of these types of movement remain poorly understood. This study examined the effects of movement frequency and medication on the performance of unconstrained index finger flexion movements in patients with PD and matched control subjects. Movements were synchronized with an auditory tone as the frequency of the tone was increased from 1 to 3 Hz in 0.25 Hz increments. Movement performance was quantified based upon finger kinematics and electromyography (EMG) recorded from the index finger flexors and extensors. The principal finding was that patients with PD showed a dramatic reduction in movement amplitude, an increase in movement frequency, and a loss of phase when the movement frequency reached or exceeded 2 Hz. This deficit was not significantly improved with medications. In contrast, all control subjects could synchronize to 3 Hz. These findings show that movement frequency is a major determinant of hypokinesia during repetitive movements and may contribute to hesitations and movement arrest during clinical testing of bradykinesia in the upper limb of patients with PD. © 2009 Movement Disorder Society
Pain intensity on and off levodopa in patients with Parkinson's disease
Authors: Nebe Angelika , Ebersbach Georg 
Published: May 2009

AbstractPain is frequently reported by patients with Parkinson's disease (PD). In this study, intensity of pain as measured by a visual analogue scale (VAS) was assessed on and off levodopa in 15 patients with PD. All patients had motor fluctuations and suffered from pain of various types. Description of pain was assessed with the McGill pain questionnaire. Ratings for pain intensity on the VAS were increased during off period for all patients but one (P = 0.001). There was a correlation (P = 0.04) between changes in motor performance (Unified Parkinson's Disease Rating Scale part III) and pain intensity (VAS). Compared with a historical sample of subjects with different pain syndromes without PD, terms related to fear and punishment were used more frequently by patients with PD in this study. In two patients, pain was exclusively limited to the off period. The majority of subjects suffered from secondary pain possibly related to lumbar osteoarticular degeneration. Secondary pain was relieved but not completely abolished by levodopa. The results of this study suggest that aggravation of secondary pain should be considered as a part of the spectrum of nonmotor off symptoms. Analgesics should not be given as first line drugs when pain occurs or increases in off conditions, and pain can be significantly alleviated or abolished by adjustments of dopaminergic medication. © 2009 Movement Disorder Society
Perverted head‐shaking and positional downbeat nystagmus in patients with multiple system atrophy
Authors: Lee Jee‐Young , Lee Woong‐Woo , Kim Ji Soo , Kim Hee Jin , Kim Jin‐Kyung , Jeon Beom S. 
Published: May 2009

AbstractThe diagnosis of multiple system atrophy (MSA) is mainly based on the clinical criteria, which are often of little assistance in the early stages of the disease. Positional downbeat nystagmus (pDBN) and perverted head‐shaking nystagmus (pHSN), possible signs of cerebellar dysfunction, may be useful in differentiating MSA from other parkinsonian disorders. To investigate the occurrences of pDBN and pHSN in patients with MSA compared with those in patients with Parkinson's disease (PD). A total of 127 consecutive patients with MSA and 274 patients with PD underwent a video‐oculographic recording of head‐shaking and positional nystagmus over a year. The occurrences of pDBN and pHSN were higher in MSA than in PD. pDBN was more frequently observed in MSA with overt cerebellar signs than in those without, but the occurrence of pHSN did not differ between the MSA groups. pHSN was more frequently observed in MSA‐p without overt cerebellar signs than in PD, but there was no difference in the occurrence of pDBN between them. The presence of pHSN and pDBN may be a clue for the diagnosis of MSA, and pHSN may be helpful in differentiating MSA‐p from PD when the patients do not have overt cerebellar features. © 2009 Movement Disorder Society
The course of depressive symptoms in early Parkinson's disease
Authors: Ravina Bernard , Elm Jordan , Camicioli Richard , Como Peter G. , Marsh Laura , Jankovic Joseph , Weintraub Daniel 
Published: May 2009

AbstractLittle is known about the course of depressive symptoms in Parkinson's disease (PD). We studied the course of clinically significant depressive symptoms using data from two clinical trials that followed 413 early, untreated PD subjects for 12 to 18 months. We measured depressive symptoms with the 15‐item geriatric depression scale (GDS‐15); a score of ≥5 indicates clinically significant depressive symptoms. We used a time‐dependent Cox model to examine the association between demographic variables, PD severity, and medication use on the time to resolution of depressive symptoms. One hundred fourteen of 413 (27.6%) subjects were screened positive for depression during the study, with a median GDS‐15 score of 6, indicating mild symptoms. Within 6 months, 47% of subjects experienced remission of clinically significant depressive symptoms. Subjects with mild depressive symptoms were more likely to develop moderate to severe depressive symptoms (GDS ≥ 10) than those without prior symptoms (relative risk = 6.16). Increasing severity of depressive symptoms, older age, and longer PD duration predicted a lower likelihood of symptom resolution (hazard ratios 0.83–0.92). Mild depressive symptoms have a variable course, with remission and development of more sustained and severe symptoms occurring over time. More severe depressive symptoms may herald a protracted course. © 2009 Movement Disorder Society
Cerebellar involvement in progressive supranuclear palsy: A clinicopathological study
Authors: Kanazawa Masato , Shimohata Takayoshi , Toyoshima Yasuko , Tada Mari , Kakita Akiyoshi , Morita Takashi , Ozawa Tetsutaro , Takahashi Hitoshi , Nishizawa Masatoyo 
Published: May 2009

AbstractThe clinical heterogeneity of progressive supranuclear palsy (PSP), which is classified as classic Richardson's syndrome (RS) and PSP‐Parkinsonism (PSP‐P), has been previously discussed. We retrospectively analyzed 22 consecutive Japanese patients with pathologically proven PSP to investigate the clinicopathological heterogeneity. We investigated the clinical features both early in and at any time during the disease course. The pathological severities of neuronal loss with gliosis and tau pathology were also evaluated. On the basis of the clinical features, 10 patients were categorized as having RS, and 8 were categorized as having PSP‐P. Four patients presenting with cerebellar ataxia or cerebral cortical signs were categorized as having unclassifiable PSP. Among them, 3 developed cerebellar ataxia as the initial and principal symptom. Notably, tau‐positive inclusion bodies in Purkinje cells were significantly more frequently observed in the patients with cerebellar ataxia than in those without cerebellar ataxia. All the patients with cerebellar ataxia exhibited more neuronal loss with gliosis and higher densities of coiled bodies in the cerebellar dentate nucleus than those without cerebellar ataxia. This study confirms the wide spectrum of clinicopathological manifestations associated with PSP regardless of different ethnic origin, and demonstrates that PSP patients manifest cerebellar ataxia. © 2009 Movement Disorder Society