bluuebunny/crossref_metadata_2025 huggingface dataset:
Westerly Wind Bursts and Their Relationship with Intraseasonal Variations and ENSO. Part I: Statistics
Authors: Seiki Ayako , Takayabu Yukari N.
Published: October 2007

Statistical features of the relationship among westerly wind bursts (WWBs), the El Niño–Southern Oscillation (ENSO), and intraseasonal variations (ISVs) were examined using 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis data (ERA-40) for the period of January 1979–August 2002. WWBs were detected over the Indian Ocean and the Pacific Ocean, but not over the Atlantic Ocean. WWB frequencies for each region were lag correlated with a sea surface temperature anomaly over the Niño-3 region. WWBs tended to occur in sequence, from the western to eastern Pacific, leading the El Niño peak by 9 months to 1 month, respectively, and after around 11 months, over the Indian Ocean. These results suggest that WWB occurrences are not random, but interactive with ENSO. Composite analysis revealed that most WWBs were associated with slowdowns of eastward-propagating convective regions like the Madden–Julian oscillation (MJO), with the intensified Rossby wave response. However, seasonal and interannual variations in MJO amplitude were not correlated with WWB frequency, while a strong MJO event tended to bear WWBs. It is suggested that the strong MJO amplitude promotes favorable conditions, but it is not the only factor influencing WWB frequency. An environment common to WWB generation in all regions was the existence of background westerlies around the WWB center near the equator. It is inferred that ENSO prepares a favorable environment for the structural transformation of an MJO, that is, the intensified Rossby wave response, that results in WWB generations. The role of the background wind fields on WWB generations will be discussed in a companion paper from the perspective of energetics.
Preemptive Forecasts Using an Ensemble Kalman Filter
Authors: Etherton Brian J.
Published: October 2007

An ensemble Kalman filter (EnKF) estimates the error statistics of a model forecast using an ensemble of model forecasts. One use of an EnKF is data assimilation, resulting in the creation of an increment to the first-guess field at the observation time. Another use of an EnKF is to propagate error statistics of a model forecast forward in time, such as is done for optimizing the location of adaptive observations. Combining these two uses of an ensemble Kalman filter, a “preemptive forecast” can be generated. In a preemptive forecast, the increment to the first-guess field is, using ensembles, propagated to some future time and added to the future control forecast, resulting in a new forecast. This new forecast requires no more time to produce than the time needed to run a data assimilation scheme, as no model integration is necessary. In an observing system simulation experiment (OSSE), a barotropic vorticity model was run to produce a 300-day “nature run.” The same model, run with a different vorticity forcing scheme, served as the forecast model. The model produced 24- and 48-h forecasts for each of the 300 days. The model was initialized every 24 h by assimilating observations of the nature run using a hybrid ensemble Kalman filter–three-dimensional variational data assimilation (3DVAR) scheme. In addition to the control forecast, a 64-member forecast ensemble was generated for each of the 300 days. Every 24 h, given a set of observations, the 64-member ensemble, and the control run, an EnKF was used to create 24-h preemptive forecasts. The preemptive forecasts were more accurate than the unmodified, original 48-h forecasts, though not quite as accurate as the 24-h forecast obtained from a new model integration initialized by assimilating the same observations as were used in the preemptive forecasts. The accuracy of the preemptive forecasts improved significantly when 1) the ensemble-based error statistics used by the EnKF were localized using a Schur product and 2) a model error term was included in the background error covariance matrices.
Total Lightning Signatures of Thunderstorm Intensity over North Texas. Part II: Mesoscale Convective Systems
Authors: Steiger Scott M. , Orville Richard E. , Carey Lawrence D.
Published: October 2007

Total lightning data from the Lightning Detection and Ranging (LDAR II) research network in addition to cloud-to-ground flash data from the National Lightning Detection Network (NLDN) and data from the Dallas–Fort Worth, Texas, Weather Surveillance Radar-1988 Doppler (WSR-88D) station (KFWS) were examined from individual cells within mesoscale convective systems that crossed the Dallas–Fort Worth region on 13 October 2001, 27 May 2002, and 16 June 2002. LDAR II source density contours were comma shaped, in association with severe wind events within mesoscale convective systems (MCSs) on 13 October 2001 and 27 May 2002. This signature is similar to the radar reflectivity bow echo. The source density comma shape was apparent 15 min prior to a severe wind report and lasted more than 20 min during the 13 October storm. Consistent relationships between severe straight-line winds, radar, and lightning storm cell characteristics (e.g., lightning heights) were not found for cells within MCSs as was the case for severe weather in supercells in Part I of this study. Cell interactions within MCSs are believed to weaken these relationships as reflectivity and lightning from nearby storms contaminate the cells of interest. Another hypothesis for these weak relations is that system, not individual cell, processes are responsible for severe straight-line winds at the surface. Analysis of the total lightning structure of the 13 October 2001 MCS showed downward-sloping source density contours behind the main convective line into the stratiform region. This further supports a charge advection mechanism in developing the stratiform charge structure. Bimodal vertical source density distributions were observed within MCS convection close to the center of the LDAR II network, while the lower mode was not detected at increasing range.
Observed Enhancement of Reflectivity and the Electric Field in Long-Lived Florida Anvils
Authors: Dye James E. , Willett John C.
Published: October 2007

A study of two long-lived Florida anvils showed that reflectivity >20 dBZ increased in area, thickness, and sometimes magnitude at the midlevel well downstream of the convective cores. In these same regions electric fields maintained strengths >10 kV m−1 for many tens of minutes and became quite uniform over tens of kilometers. Millimetric aggregates persisted at 9–10 km for extended times and distances. Aggregation of ice particles enhanced by the strong electric fields might have contributed to reflectivity growth in the early anvil, but is unlikely to explain observations farther out in the anvil. The enhanced reflectivity and existence of small, medium, and large ice particles far out into the anvil suggest that an updraft was acting, perhaps in weak convective cells formed by instability generated from the evaporation and melting of falling ice particles. It is concluded that charge separation must have occurred in these anvils, perhaps at the melting level but also at higher altitudes, in order to maintain fields >10 kV m−1 at 9–10 km for extended periods of time over large distances. The authors speculate that charge separation occurred as a result of ice–ice particle collisions (without supercooled water being present) via either a noninductive or perhaps even an inductive mechanism, given the observed broad ice particle spectra, the strong preexisting electric fields, and the many tens of minutes available for particle interactions. The observations, particularly in the early anvil, show that the charge structure in these anvils was quite complex.
The Interaction between Two Separate Propagations of Rossby Waves
Authors: Wang Yafei , Yamazaki Koji , Fujiyoshi Yasushi
Published: October 2007

This study deals with two teleconnection patterns and the subsequent wave train propagations during an East Asian summer. Diagnostic results are as follows: 1) a stationary wave ray with zonal wavenumber 5 approximates the arc path linking the correlation centers originating from the Caspian Sea via Lake Baikal to the sea off the southeast coast of Japan (i.e., the OKJ arc path as a focus area) in a pentad correlation map between 500-hPa geopotential height (Z500) and outgoing longwave radiation (OLR) at 30°N, 150°E in June 1979–98. Ray tracing shows that it took 8–10 days for this stationary wave to propagate from an initial position around the Caspian Sea to the focus area, which roughly coincides with the observed case in July 1998. 2) A wave train pattern (P-Ja) observed in the boreal summer propagated along the arc line in the same way as the normal poleward Rossby wave train originating from the Philippines across the North Pacific (P-J), but with a phase shift northeastward of about 90°. 3) Further correlation analyses showed that the P-J-like waves belong mainly to intraseasonal propagating ones while OKJ waves belong mainly to intraseasonal stationary ones. 4) Propagation of the newly observed wave train pattern (P-Ja) occurred following another wave train along the OKJ arc path in mid-July 1998. Both northeastward and southeastward wave propagations merged off the east coast of Japan. 5) The northeastward-propagating wave train observed in mid-July 1998 was triggered by the southeastward-propagating (OKJ) wave train that produced a deep cyclonic circulation and a strong convective activity in the focus area. The link of wave forcing and deep convection was made solely because of a strong upper-level divergence in the focus area.
Westerly Wind Bursts and Their Relationship with Intraseasonal Variations and ENSO. Part II: Energetics over the Western and Central Pacific
Authors: Seiki Ayako , Takayabu Yukari N.
Published: October 2007

The mechanism of synoptic-scale eddy development in the generation of westerly wind bursts (WWBs) over the western–central Pacific, and their relationship with the El Niño–Southern Oscillation (ENSO) and the Madden–Julian oscillation (MJO), were examined. In the WWB occurrences, barotropic structures of equatorial eddy westerlies with cyclonic disturbances were found from the surface to the upper troposphere. The dominant contributions to substantial eddy kinetic energy (EKE) were the barotropic energy conversion (KmKe) in the lower and middle tropospheres and the conversion from eddy available potential energy (PeKe) in the upper troposphere. Low-frequency environmental westerlies centered near the equator preceded strong zonal convergence and meridional shear, resulting in the substantial KmKe. The activation of synoptic convection also contributed to an increase in EKE through PeKe. These energies were redistributed to the lower-equatorial troposphere through energy flux convergence (GKe). These results showed that environmental fields contribute to the EKE increase near the equator and are important factors in WWB occurrences. Next, eddy growth was compared under different phases of MJO and ENSO. The MJO westerly phases of strong MJO events were classified into two groups, in terms of ENSO phases. Higher EKE values were found over the equatorial central Pacific in the WWB–ENSO correlated (pre–El Niño) periods. The energetics during these periods comported with those of the WWB generations. In the uncorrelated periods, the enhancement of eddy disturbances occurred far from the equator near the Philippines, where the activities of the easterly wave disturbances are well known. It is noteworthy that the enhanced region of the disturbances in the pre–El Niño periods coincided with the vicinity of large-scale MJO convection. It is suggested that coincidence corresponds with an enhancement of the internal disturbances embedded in the MJO, which is found only when the environmental conditions are favorable in association with ENSO.
Assessing Variation in Civil Society Organizations
Authors: Read Benjamin L.
Published: October 2007

Theories of civil society set high expectations for grassroots associations, claiming that they school citizens in democracy and constrain powerful institutions. But when do real-life organizations actually live up to this billing? Homeowner organizations in the United States and elsewhere have sparked debate among political scientists, criticized by some as nonparticipatory and harmful to the overall polity and defended by others as benign manifestations of local self-governance. With this as a backdrop, China's emerging homeowner groups are used as a testing ground for exploring variation in three criteria of performance: self-organization, participation, and the exercising of power. Comparisons are drawn cross-nationally, among 23 cases in four Chinese cities and over time within neighborhoods. The article puts forward several factors affecting the properties of grassroots groups, highlighting the role of conflict, the political—legal environment, and collective action problems in shaping the way they engage their members and take political action.
Contingencies of Self-Worth, Academic Failure, and Goal Pursuit
Authors: Park Lora E. , Crocker Jennifer , Kiefer Amy K.
Published: October 2007

Two studies examine the effects of failure on explicit and implicit self-esteem, affect, and self-presentation goals as a function of people's trait self-esteem and academic contingency of self-worth. Study 1 shows that participants with low self-esteem (LSE) who receive failure feedback experience lower state self-esteem, less positive affect, and less desire to be perceived as competent the more they base self-worth on academics. In contrast, participants with high self-esteem (HSE) who strongly base self-worth on academics show a slight boost in state self-esteem and desire to be perceived as competent following failure. Study 2 shows that following failure, academically contingent LSE participants downplay the importance of appearing competent to others and associate themselves with failure on an implicit level. Taken together, these findings suggest that academically contingent HSE people show resilience following failure, whereas academically contingent LSE people experience negative outcomes and disengage from the pursuit of competence self-presentation goals.
One-Shot Illusory Correlations and Stereotype Formation
Authors: Risen Jane L. , Gilovich Thomas , Dunning David
Published: October 2007

In four studies, the authors explored the emergence of one-shot illusory correlations—in which a single instance of unusual behavior by a member of a rare group is sufficient to create an association between group and behavior. In Studies 1, 2, and 3, unusual behaviors committed by members of rare groups were processed differently than other types of behaviors. They received more processing time, prompted more attributional thinking, and were more memorable. In Study 4, the authors obtained evidence from two implicit measures of association that one-shot illusory correlations are generalized to other members of a rare group. The authors contend that one-shot illusory correlations arise because unusual pairings of behaviors and groups uniquely prompt people to entertain group membership as an explanation of the unusual behavior.
Ideological and Personal Zeal Reactions to Threat Among People With High Self-Esteem: Motivated Promotion Focus
Authors: McGregor Ian , Gailliot Matthew T. , Vasquez Noelia A. , Nash Kyle A.
Published: October 2007

After a mortality salience manipulation, participants completed measures of either ideological zeal (Study 1) or personal project zeal (Study 3). Mortality salience increased both kinds of zeal but only among participants with high self-esteem. High self-esteem was positively correlated with dispositional tendencies toward promotion focus, action orientation, and behavioral activation; it was negatively correlated with behavioral inhibition and rumination (Study 2). These findings clarify the role of dispositional self-esteem in mortality salience research and confirm that, as has been found with various other threats, zealous reactions to mortality salience are most pronounced among participants with high self-esteem. Results support a regulatory focus perspective on zealous reactions to threat. Ideological and personal zeal reflect motivated promotion focus reactions that are rewarding because they decrease the motivational relevance, regulatory fit, and subjective salience of threats.
Why Do Some Men Misperceive Women's Sexual Intentions More Frequently Than Others Do? An Application of the Confluence Model
Authors: Jacques-Tiura Angela J. , Abbey Antonia , Parkhill Michele R. , Zawacki Tina
Published: October 2007

Although many researchers have documented men's tendency to misperceive women's friendliness as a sign of sexual interest, few have examined individual differences in men's attitudes and past experiences that might predict their likelihood of making these types of misjudgments. We applied an expanded version of Malamuth, Sockloskie, Koss, and Tanaka's (1991) Confluence model to predict frequency of misperception of women's sexual intent with a sample of 356 male college students. Using structural equation modeling, hostile masculinity, impersonal sex, and drinking in dating and sexual situations predicted men's frequency of misperception. Furthermore, the more risk factors men possessed, the more times they misperceived women's sexual intentions. Suggestions are made for theory development and future research incorporating situational as well as personality measures in longitudinal studies.
Feelings About Language Brokering and Family Relations Among Mexican American Early Adolescents
Authors: Weisskirch Robert S.
Published: October 2007

Children and adolescents of immigrant and non-English proficient parents often translate for their parents and other adults, a practice known as language brokering. The personal and emotional impact for adolescents of having to language broker for parents is not well understood. Ninety-eight Mexican American 7th graders (female = 47, male = 49, and did not state = 2) answered a questionnaire about their language brokering experience, their emotions experienced when language brokering, their level of self-esteem, and problems within the family. Participants who had more problematic family relations had higher ratings of negative emotions such as feeling angry, anxious, ashamed, calm, embarrassed, nervous, obligated, scared, uncomfortable, and worried when language brokering. Self-esteem related to translating for parents, for friends, for other people who work at school, and at a restaurant. Negative language brokering experiences may be symptomatic of poor family functioning or intrapsychic variables more than just discomfort with acting as a language broker.
Coping With Academic Failure
Authors: Altermatt Ellen Rydell
Published: October 2007

This study examined gender differences in the interactions early adolescent students report having with significant others following academic failure and the consequences of these interactions for student worry. The 5th- through 8th-grade students ( N = 297) reported on their general strategies for coping with academic failure, the nature of their everyday interactions with family members and friends following failure, and their levels of academic worry. Gender differences emerged in students' reports of their postfailure interactions and the consequences of these interactions for student worry. The findings are consistent with evidence that girls' interactions are more supportive than boys' interactions but that these seemingly supportive interactions may lead to some negative rather than positive outcomes, including worry.
Dynamic Simulation of Fusion Process and Analysis of Flow Field
Authors: Zheng Supei , Ouyang Jie , Zhang Ling , Zhang Hongping
Published: October 2007

Level set/ghost method for weldlines in the filling stage of injection molding is introduced in this article. The algorithm is based on non-isothermal, incompressible, generalized Hele-Shaw flow of a viscous fluid. The physical controlling equation systems are numerically simulated by the general finite difference scheme. Level set/ghost method captures the location and shape of the weldlines accurately and efficiently, the controlling equations of which are discretized by the fifth order weighted essentially non-oscillatory (WENO) scheme in space and by the total variation differencing Runge-Kutta (TVD-RK) method in time. As a result, the fusion process of weldlines is simulated accurately and the analysis of flow field is given correctly. Examples verify the proposed methodology.
Hygro-elastic Internal Stresses in Porous Composite Materials: A Multi-scale Analysis
Authors: Youssef Z. , Jacquemin F. , Gloaguen D. , Guillén R.
Published: October 2007

A multi-scale approach is devoted to the analysis of hygro-elastic internal stresses in porous composite materials. Voids in composite materials are known to cause a significant reduction of mechanical properties. Moreover, in a humid environment they also affect the moisture absorption and the induced internal stresses. In this work, a self-consistent approach is used to estimate internal stresses induced by moisture absorption in composite materials with porous matrices. This work shows that the interaction between voids and moisture has a severe impact on the transient hygro-elastic stresses at both microscopic (fiber and matrix) and macroscopic (ply) scales.
Buckling and Free Vibration Analysis of Symmetric and Antisymmetric Laminated Composite Plates on an Elastic Foundation
Authors: Akavci S.S.
Published: October 2007

Buckling and free vibration analysis of simply supported symmetric and antisymmetric cross-ply thick composite plates on elastic foundation are examined by a new hyperbolic displacement model in this paper. In this new model, inplane displacements vary as a hyperbolic function across the plate thickness, so account for parabolic distributions of transverse shear stresses and satisfy zero shear stress conditions at the top and bottom surfaces of the plate. In the analysis, the foundation is modeled as two parameter Pasternak type foundation, and Winkler type if the second foundation parameter is zero. The equation of motion for thick laminated rectangular plates resting on elastic foundation and subjected to inplane loads is obtained through Hamilton's principle. The closed form solutions are obtained by using Navier technique, and then buckling loads and fundamental frequencies are found by solving the results of eigenvalue problems. The numerical results obtained through the present analysis for free vibration and buckling of cross-ply laminated plates on elastic foundation are presented, and compared with the ones available in the literature.
Statistical Formulation for Time-temperature Dependent Flexural Strength of CFRP Laminates
Authors: Noda Junji , Nakada Masayuki , Miyano Yasushi
Published: October 2007

Statistical formulations of the master curves for the constant strain rate (CSR), creep and fatigue strengths of CFRP laminates, which depend on time and temperature as well as the number of cycles to failure, are proposed, based on Christensen's theory which describes statistically the crack kinetics in viscoelastic body. The master curves of these strengths of the plain-woven fabric T300/vinylester CFRP, the flat fabric T700/vinylester CFRP and the multi-axial knitted fabric T700/vinylester CFRP laminates were measured by the accelerated testing methodology in our previous paper. The quantitative characteristics of CSR, creep and fatigue master curves for these CFRP laminates are discussed using the results of our statistical formulations. Finally, it is demonstrated that our formulation of the master curves is available and practical for long-term durability design for CFRP laminate.
Applicability of the Student—Teacher Relationship Scale (STRS) in the Greek Educational Setting
Authors: Gregoriadis Athanasios , Tsigilis Nikolaos
Published: October 2007

The present study examined the applicability of the Student—Teacher Relationship Scale (STRS) within the Greek cultural context. Sixty-seven kindergarten teachers filled in a Greek version of the STRS concerning 403 kindergarten students. Exploratory factor analysis showed that a 26-item version of the STRS could be considered as a valid and reliable instrument to measure Closeness (α = .86), Conflict (α = .87) and Dependency (α = .79). Findings further indicated that teachers described young boys as having more conflictual relationships with their teachers and young girls as having closer and more dependent relationships with them. In contrast with previous studies, the Dependency subscale was positively correlated with the Closeness subscale ( r = .34) and did not associate with the Conflict subscale. These findings might be attributed to the different cultural background of the Greek kindergarten teachers or their differentiated interpretation of the notion of dependency.
Model Predictive Control of a Two Stage Actuation System using Piezoelectric Actuators for Controllable Industrial and Automotive Brakes and Clutches
Authors: Neelakantan Vijay A. , Washington Gregory N. , Bucknor Norman K.
Published: October 2007

High bandwidth actuation systems that are capable of simultaneously producing relatively large forces and displacements are required for use in automobiles and other industrial applications. Conventional hydraulic actuation mechanisms used in automotive brakes and clutches are complex, inefficient and have poor control robustness. These lead to reduced fuel economy, controllability issues and other disadvantages. Recently, a two-stage hybrid actuation mechanism was proposed by combining classical electromechanical actuators like DC motors and advanced smart material devices like piezoelectric actuators. This article discusses the development and implementation of a model predictive control methodology for controlling this two-stage actuation system in tracking various reference inputs. Additionally, this methodology also employs a unit-step delayed disturbance estimate to account for actuator hysteresis, other nonlinearities and unmodeled dynamics in the system. Finally, the article highlights the effectiveness of this control methodology experimentally by tracking various reference inputs.
Biaxial Constrained Recovery in Shape Memory Alloy Rings
Authors: Videnic Tomaz , Kosel Franc , Sajn Viktor , Brojan Miha
Published: October 2007

In this article biaxial constrained recovery in a thick-walled shape memory alloy (SMA) ring with a rectangular cross-section is modeled using the theory of generalized plasticity, which is developed by Jacob Lubliner and Ferdinando Auricchio. As a mechanical obstacle that delays free recovery in a SMA ring, a steel ring is used. The result of constrained recovery is the generation of high stresses in both the rings. All equations are written in a closed form in terms of infinite series. Theoretical results are compared with experimental findings and good agreement is found when SMA rings are in the domain of recoverable strains.
Modal Analysis on Macro-strain Measurements from Distributed Long-gage Fiber Optic Sensors
Authors: Suzhen Li  , Zhishen Wu
Published: October 2007

In a recent study by the authors, an advanced structural health monitoring (SHM) strategy based on distributed fiber optic sensing techniques has been proposed to utilize the strain responses throughout the full or some partial areas of structures to detect the arbitrary and unforeseen damages. As one of the essential components, a two-level scheme based on modal parameters from distributed dynamic macro-strain responses has been developed for damage locating and quantifying. This work further investigates the superiority and some concerns of using distributed long-gage fiber optic sensing technique for vibration based SHM through a theoretical modal analysis on the dynamic macro-strain distribution. Modal testing is also carried out to verify the performance of macro-strain frequency response function (FRF) and identify the modal parameters including resonant frequency, damping ratio, and modal macro-strain vector (MMSV). From the SHM point of view, their applications are summarized finally.
An Experimental Study of Semiactive Modal Neuro-control Scheme Using MR Damper for Building Structure
Authors: Lee Heon-Jae , Jung Hyung-Jo , Cho Sang-Won , Lee In-Won
Published: October 2007

In this study, a semiactive modal neuro-control scheme which combines the modal neuro-control algorithm with a semiactive MR damper is proposed, and its effectiveness is experimentally verified through a series of shaking table tests. A modal neuro-control scheme uses modal coordinates as inputs of neuro-controller. Hence, it is more convenient to design the controller compared with conventional neuro-control schemes. A Kalman filter is introduced to estimate modal states from measurements. Moreover, the clipped algorithm is adopted to provide an appropriate command voltage to an MR damper. For shaking table tests, a scaled three-story shear building model is considered. Two types of semiactive modal neuro-controllers are trained with a reproduced El Centro earthquake for their own purposes. The performance of the proposed semiactive modal neuro-control scheme is compared with that of the passive-optimal case. In the experiments, the proposed semiactive modal neuro-controllers show better performance than the passive-optimal case, especially in adaptability over various excitations and reducing inter-story drifts as well as accelerations. Moreover, the proposed scheme can be designed for specific purpose which fulfills the designer's requirement (e.g., focusing on reducing inter-story drifts). Therefore, the proposed semiactive modal neuro-controller can be effectively used in reducing seismic responses of large engineering structures.
An Elliptic Thermopiezoelectric Inclusion Problem in An Anisotropic Thermopiezoelectric Medium
Authors: Longchao Dai  , Xinwei Wang
Published: October 2007

This study presents an analytical solution for an elliptical anisotropic piezoelectric inclusion embedded in an infinite anisotropic piezoelectric matrix subjected to arbitrary far-field uniform loadings by employing the Stroh formalism, the method of analytical continuation, the technique of conformal mapping, and the concept of superposition. Solutions of the temperature and stress functions either in the matrix or in the inclusion are expressed in complex matrix notation. It shows that the mechanic and electric loading leads to the appearance of the constant stress fields in the inclusion and the heat flux only leads to that of the linear stress fields. Comparison with some related works shows that the present solutions are valid and general.
Why Using Current Medications to Select a Medicare Part D Plan May Lead to Higher Out-of-Pocket Payments
Authors: Domino Marisa Elena , Stearns Sally C. , Norton Edward C. , Yeh Wei-Shi
Published: October 2007

While medications are one of the most stable categories of health care expenses, the actual composition of drug products used may be highly variable over time. Medicare beneficiaries selecting among Part D prescription drug plans (PDPs) are often advised to base plan selection on current medication lists. However, this approach may lead to higher out-of-pocket payments relative to payments under other plans if drug switches are common. This article uses a sample of Medicare beneficiaries from the 2003 Medical Expenditure Panel Survey to estimate how changes in actual drug use during a 1-year period affect estimated annual costs, given the initial choice of the lowest-cost PDP. While 57% of the sample had no difference in expenditure for plans selected based on initial versus end-of-the-year drug lists, 43% experienced average increases of $556 in annualized expenses due to drug switches. Implementable suggestions for improving the selection of Part D plans are provided.
Validation of the Multiple Sclerosis International Quality of Life questionnaire
Authors: Simeoni MC , Auquier P. , Fernandez O. , Flachenecker P. , Stecchi S. , Constantinescu CS , Idiman E. , Boyko A. , Beiske AG , Vollmer T. , Triantafyllou N. , O'Connor P. , Barak Y. , Biermann L. , Cristiano E. , Atweh S. , Patrick DL , Robitail S. , Ammoury N. , Beresniak A. , Pelletier J.
Published: October 2007

This study aims to validate the Multiple Sclerosis (MS) International Quality of Life (MusiQoL) questionnaire, a multi-dimensional, self-administered questionnaire, available in 14 languages, as a disease-specific quality of life scale that can be applied internationally. A total of 1992 patients with different types and severities of MS from 15 countries were recruited. At baseline and day 21 ± 7, each patient completed the MusiQoL, a symptom checklist and the short-form (SF)-36 QoL questionnaire. Neurologists also collected socio-demographic, MS history and outcome data. The database was randomly divided into two subgroups and analysed according to different patient characteristics. For each model, psychometric properties were tested and the number of items was reduced by various statistical methods. Construct validity, internal consistency, reproducibility and external consistency were also tested. Nine dimensions, explaining 71% of the total variance, were isolated. Internal consistency and reproducibility were satisfactory for all the dimensions. External validity testing revealed that dimension scores correlated significantly with all SF-36 scores, but showed discriminant validity by gender, socio-economic and health status. Significant correlations were found between activity in daily life scores and clinical indices. These results demonstrate the validity and reliability of the MusiQoL as an international scale to evaluate QoL in patients with MS. Multiple Sclerosis 2008; 14: 219—230. http://msj.sagepub.com
Restless legs syndrome is a common finding in multiple sclerosis and correlates with cervical cord damage
Authors: Manconi M. , Rocca M.A. , Ferini-Strambi L. , Tortorella P. , Agosta F. , Comi G. , Filippi M.
Published: October 2007

In this prospective study, we estimated the prevalence of restless legs syndrome (RLS) in multiple sclerosis (MS) patients, and compared the extent of brain and cervical cord damage between patients with and without RLS using conventional and diffusion tensor magnetic resonance imaging (MRI). Eighty-two consecutive MS patients were evaluated. Each patient underwent a medical history interview, a neurological examination and brain/cervical cord MRI. Global and regional dual-echo lesion load (LL), number of cervical cord lesions, mean diffusivity (MD) and fractional anisotropy (FA) histograms metrics of the normal-appearing tissues of the brain and cervical cord were assessed. Thirty subjects had RLS; they showed a higher Expanded Disability Status Scale score than patients without. No difference between the two groups was found in whole brain, cerebellar and brainstem T2-LLs; MD and FA histograms derived metrics of the normal appearing brain tissues; basal ganglia MD; number of cervical cord lesions and cord MD histograms derived metrics. Cervical cord average FA was significantly reduced in MS patients with RLS compared to those without. RLS symptoms are very common in MS. This form of RLS should be considered as symptomatic. Higher disability and cervical cord damage represent a significant risk factor for RLS in MS patients. Multiple Sclerosis 2008; 14: 86—93. http://msj.sagepub.com
Retrospective comparison of the original and revised McDonald criteria in a general neurology practice in Ireland
Authors: McHugh J.C. , Galvin P.L. , Murphy R.P.
Published: October 2007

Background The McDonald criteria were introduced in 2001 as guidelines to facilitate early and accurate diagnosis of multiple sclerosis (MS). They were revised in 2005. Although validated in a number of research-focused clinical centres, their adequacy and utility in the general neurology setting is less certain.

Objective In this study, we assessed new diagnoses of MS in our practice for compliance with both the original and the revised criteria.

Methods We retrospectively identified new diagnoses of MS from 2001. Clinical notes and imaging were evaluated for compliance with McDonald criteria.

Results Sixty-two patients were included: 53 with `practice-definite' and nine with `practice-possible' diagnoses of MS. At the time of diagnosis, 47% of the `practice-definite' group fulfilled the 2001 criteria and 49% the revised criteria. Among patients not satisfying the criteria at time of diagnosis, 21% went on to fulfil the McDonald criteria over the 23-month follow-up.

Conclusions There is a considerable gap between the clinical diagnosis of MS in a general neurology setting and compliance with the McDonald criteria. Failure to perform follow-up MRI on patients with clinically isolated syndromes is a sizeable factor in this diagnostic-gap and needs to be improved. In this setting, practical differences between the original and revised criteria appear to be small.
Effects of interferon-β on co-signaling molecules: upregulation of CD40, CD86 and PD-L2 on monocytes in relation to clinical response to interferon-β treatment in patients with multiple sclerosis
Authors: Wiesemann Elke , Deb Milani , Trebst Corinna , Hemmer Bernhard , Stangel Martin , Windhagen Anja
Published: October 2007

Interferon-beta (IFN-β) reduces disease activity in a subgroup of patients with relapsing remitting multiple sclerosis (MS). The mechanism of action as well as the pathophysiological basis of responsiveness to IFN-β is not well understood. Since T-cell activation plays an important part in the pathophysiology of MS, we here investigated the effect of IFN-β on the expression of co-signaling pathways (CD28—CD80/CD86, CD154—CD40, ICOS—ICOSL, PD-1—PD-L1/2) in MS patients and correlated the results with the clinical response to IFN-β in individual patients. Expression of co-signaling molecules was measured by flow cytometry in vitro on peripheral blood mononuclear cells after incubation with IFN-β, and in vivo in whole blood samples of 32 untreated and 24 IFN-β treated MS patients, including 13 patients longitudinal. IFN-β treatment induced upregulation of CD40, CD80, CD86, PD-L1 and PD-L2 on monocytes as well as PD-L1 on CD4+-T-cells in vitro and in vivo. IFN-β treated MS patients were grouped into responders and non-responders on the basis of Kurtzkés EDSS (expanded disability status scale) progression and relapse rate. Upregulation of CD40, CD86 and PD-L2 on monocytes was associated with treatment response to IFN-β ( P < 0.001, P = 0.028 and P = 0.028, respectively). Our results show that IFN-β upregulates co-stimulatory as well as co-inhibitory molecules in vitro and in vivo implicating that modulation of the balance between positive and negative co-stimulatory signals might be an important part of the mechanism of action of IFN-β in MS. Upregulation of the expression of CD40, CD86 and PD-L2 may be useful as a predictive marker for clinical response to IFN-β treatment at early timepoints during IFN-β therapy. Multiple Sclerosis 2008; 14: 166—176. http://msj.sagepub.com
Acute 'upside-down' visual inversion due to multiple sclerosis
Authors: Okuyucu Esra Emine , Okuyucu Semsettin , Karazincir Sinem , Akoglu Ertap , Duman Taskin
Published: October 2007

In a 20-year-old male patient, a 180 degree inversion of visual image was found as a manifestation of multiple sclerosis. Upside down reversal of vision is not a well-known sign in multiple sclerosis. Exact mechanism is still unknown. Lesions involving cortical areas, mainly the parieto-occipital region, have occasionally been documented. To our knowledge this is the first report of upside-down reversal of vision in multiple sclerosis with cerebra lesion on MRI. Multiple Sclerosis 2008; 14: 266—267. http://msj.sagepub.com
Influence of oligoclonal IgM specificity in multiple sclerosis disease course
Authors: Villar LM , García-Barragán N. , Espiño M. , Roldán E. , Sádaba MC , Gómez-Rial J. , González-Porqué P. , Álvarez-Cermeño JC
Published: October 2007

Oligoclonal IgM bands (OCMB) against myelin lipids predict an aggressive multiple sclerosis (MS) course. However, the clinical significance of OCMB without lipid specificity, present in other MS patients, remains unknown. We describe here a characterization of these antibodies and study their role in MS progression. Fifty-four MS patients showing CSF-restricted OCMB were included in this study at disease onset and followed-up during 61.1 ± 2.7 months. The specificity of OCMB and the CSF B-cell profile were investigated. A second CSF IgM study was performed in a group of eight patients. Thirty-eight patients showed OCMB against myelin lipids (M+L+) and other sixteen had OCMB lacking this specificity (M+L-). The CD5+ B cell subpopulation, responsible for most persistent IgM responses, was considerably higher in M+L+ than in M+L- patients (3.3 ± 0.6% versus 0.8 ± 0.2, P = 0.009). In addition, M+L+ bands persisted during disease course, while M+L- disappeared during follow-up. M+L+ patients suffered more relapses (4.2 ± 0.6 versus 1.6 ± 0.3, P = 0.002) and reached higher disability (EDSS score of 2.2 ± 0.2 versus 1.2 ± 0.2, P = 0.02) than M+L- group. These data corroborate that anti-lipid OCMB associate with an aggressive MS course and show that OCMB that do not recognize myelin lipids represent a transient immune response related to a more benign disease course. Multiple Sclerosis 2008; 14: 183—187. http://msj.sagepub.com
Common infectious agents in multiple sclerosis: a case—control study in children
Authors: Krone Bernd , Pohl Daniela , Rostasy Kevin , Kahler Elke , Brunner Edgar , Oeffner Frank , Grange John M. , Gärtner Jutta , Hanefeld Folker
Published: October 2007

Environmental factors, in particular infections, have been linked with the risk of developing multiple sclerosis (MS). The association of Epstein—Barr virus infection with childhood onset of MS has been recently recognized. As other infections characteristically experienced during childhood have not yet been studied in larger cohorts of paediatric MS, we conducted a study on 152 German children with MS (age at onset <16 years) and matched controls in the hope of gaining evidence for their possible aetiological role in MS. Patterns of antibody responses were determined to a range of infections which, in prior studies principally on adult patients, had revealed possible associations with MS. In this study on children the serology of several infections showed associations with MS. In the exceptional case of Chlamydia pneumoniae there was a significantly higher prevalence of IgM antibody but, more typically, as in the case of influenza A, measles, parainfluenza 2, varicella/zoster viruses and particularly to the herpes simplex virus type 2 (HSV-2) lysate antigen, there were significantly higher concentrations of IgG antibody. Additional investigations, however, make it highly unlikely that a relevant number of children have experienced infections with HSV-2. In general this study supports and emphasizes a complex infectious and immunologic background of MS. Multiple Sclerosis 2008; 14: 136—139. http://msj.sagepub.com
Peripheral blood leukocyte NO production and oxidative stress in multiple sclerosis
Authors: Koch Marcus , Mostert Jop , Arutjunyan Alexander , Stepanov Michael , Teelken Albert , Heersema Dorothea , De Keyser Jacques
Published: October 2007

Background The reason for increased peripheral blood leukocyte (PBL) nitric oxide (NO) production in patients with multiple sclerosis (MS) is unknown.

Objective To investigate whether PBL NO production is related to measures of oxidative stress.

Methods PBL nitrite, diene conjugates (DC, a measure of undergone oxidative stress), antiradical activity (ARA) and antioxidant acitvity (AOA) were measured in 35 healthy control persons and 80 patients with MS. We investigated the correlation of these measures with a partial correlation analysis, with age as the control variable.

Results There was a significant correlation in both MS patients and healthy control persons between PBL nitrite levels and PBL DC, ARA and AOA. The correlations were stronger in healthy control persons. An analysis by disease subtype showed that the correlations were present in patients with relapsing—remitting and secondary progressive MS, but absent in primary progressive MS.

Conclusions PBL nitrite levels and measures of oxidative stress are closely related in MS-patients as well as in healthy control persons. Increased serum NO levels in MS may be the result of a physiologic reaction to overall oxidative stress. The differences in the strength of correlation between different disease subtypes may reflect differences in leukocyte biology. Multiple Sclerosis 2008; 14: 159—165. http://msj.sagepub.com
Serum uric acid levels of patients with multiple sclerosis and other neurological diseases
Authors: Fuhua Peng  , Bin Zhang  , Xiufeng Zhong  , Jin Li  , Guihong Xu  , Xueqiang Hu  , Wei Qiu  , Zhong Pei
Published: October 2007

The serum uric acid (UA) levels were measured in 112 patients with multiple sclerosis (MS) and 794 patients with different types of other neurological diseases (OND) or healthy control group. Serum UA levels, along with relevant clinical parameters of MS and OND, were also investigated. MS patients had significantly lower UA levels than those with transient ischemia attack (344.6 ± 130.6 µmol/L, P = 0.000), cerebral hemorrhage (311.9 ± 104.7 µmol/L, P = 0.000), cerebral infarction (291.3 ± 101.6 µmol/L, P = 0.014) and the healthy control group (312.1 ± 92.8 µmol/L, P = 0.000). MS patients had significantly higher serum UA levels than those with cryptococcus meningitis or meningoencephalitis (178.9 ± 107.0 µmol/L, P = 0.000) and tuberculous meningitis or meningoencephalitis patients (175.7 ± 99.9 µmol/L, P = 0.000). There were no significant differences in UA levels between patients with MS and those with facial neuritis, viral meningitis or encephalitis, pulmonary tuberculosis, polymyositis or dermatomyositis, myasthenia gravis, subarachnoid hemorrhage, migraine, Guillain—Barre syndrome and myelitis. In addition, UA levels were independently correlated with gender and duration of MS, but neither with MRI activity, disability nor subtypes of the disease in MS patients. Our data suggest that UA has two biphasic functions: neuroprotective and injurious. Our studies may help physicians to deal with conditions having abnormal UA levels. Multiple Sclerosis 2008; 14: 188—196. http://msj.sagepub.com
Multiple sclerosis and the CTLA4 autoimmunity polymorphism CT60: no association in patients from Germany, Hungary and Poland
Authors: Greve Bernhard , Simonenko Rostislav , Illes Zsolt , Peterfalvi Agnes , Hamdi Nada , Mycko Marcin P , Selmaj Krzysztof W , Rozsa Csilla , Rajczy Katalin , Bauer Peter , Berger Klaus , Weissert Robert
Published: October 2007

Polymorphisms in the CTLA4 gene region have been associated with susceptibility to autoimmune diseases. The recently described single nucleotide polymorphism CT60, located in the 3' untranslated region of CTLA4 is associated with Graves' disease, thyroiditis, autoimmune diabetes and other autoimmune diseases. A case-control association study was conducted in German, Hungarian and Polish multiple sclerosis (MS) patients and regional control individuals for the CTLA4 CT60 and + 49A/G polymorphisms. No significant association of these polymorphisms or respective haplotypes with MS was found. No association of CT60 genotypes with T cell expression of ICOS and CTLA-4 after in vitro stimulation was detected. Multiple Sclerosis 2008; 14: 153—158. http://msj.sagepub.com