bluuebunny/crossref_metadata_2025 huggingface dataset:
Decreased Delivery of Inappropriate Shocks Achieved by Remote Monitoring of ICD: A Substudy of the ECOST Trial
Authors: GUÉDON‐MOREAU LAURENCE , KOUAKAM CLAUDE , KLUG DIDIER , MARQUIÉ CHRISTELLE , BRIGADEAU FRANÇOIS , BOULÉ STÉPHANE , BLANGY HUGUES , LACROIX DOMINIQUE , CLÉMENTY JACQUES , SADOUL NICOLAS , KACET SALEM
Published: March 2014

Inappropriate Shocks Reduction by Remote ICD Monitoring

Introduction

Inappropriate shocks remain a highly challenging complication of implantable cardioverter defibrillators (ICD). We examined whether automatic wireless remote monitoring (RM) of ICD, by providing early notifications of triggering events, lowers the incidence of inappropriate shocks.

Methods and results

We studied 433 patients randomly assigned to RM (n = 221; active group) versus ambulatory follow‐up (n = 212; control group). Patients in the active group were seen in the ambulatory department once a year, unless RM reported an event requiring an earlier ambulatory visit. Patients in the control group were seen in the ambulatory department every 6 months. The occurrence of first and further inappropriate shocks, and their causes in each group were compared.

The characteristics of the study groups, including pharmaceutical regimens, were similar. Over a follow‐up of 27 months, 5.0% of patients in the active group received ≥1 inappropriate shocks versus 10.4% in the control group (P = 0.03). A total of 28 inappropriate shocks were delivered in the active versus 283 in the control group. Shocks were triggered by supraventricular tachyarrhythmias (SVTA) in 48.5%, noise oversensing in 21.2%, T wave oversensing in 15.2%, and lead dysfunction in 15.2% of patients. The numbers of inappropriate shocks delivered per patient, triggered by SVTA and by lead dysfunction, were 74% and 98% lower, respectively, in the active than in the control group.

Conclusion

RM was highly effective in the long‐term prevention of inappropriate ICD shocks.
An electron‐optical study of melt‐related microstructures in granulite facies rocks from the Torngat Orogen
Authors: Mason R. A. , Mitchell R. K. , Wirth R. , Indares A.
Published: March 2014

Cordierite–quartz and plagioclase–quartz intergrowths in a paragneiss from northern Labrador (the Tasiuyak Gneiss) were studied using SEM, STEM and TEM. The gneiss experienced granulite facies conditions and partial melting during both regional and, subsequently, during contact metamorphism. The microstructures examined all results from the contact metamorphism. Cordierite–quartz intergrowths occur on coarse and fine scales. The former sometimes exist as a ‘geometric’ intergrowth in which the interface between cordierite and quartz appears planar at the resolution of the optical microscope and SEM. The latter exists in several microstructural variants. Plagioclase is present as a minor component of the intergrowth in some examples of both the coarse and fine intergrowth. Grain boundaries in cordierite–quartz intergrowths are occupied by amorphous material or a mixture of amorphous material and chlorite. Cordierite and quartz are terminated by crystal faces in contact with amorphous material. Chlorite is sometimes found on cordierite surfaces and penetrating into cordierite grains along defects. Quartz contains (former) fluid inclusions 10–20 nm in maximum dimension. The presence of planar interfaces between cordierite and the amorphous phase is reminiscent of those between crystals and glass in volcanic rocks, but in the absence of compelling evidence that the amorphous material represents former melt, it is interpreted as a reaction product of cordierite. Plagioclase–quartz intergrowths occur in a number of microstructural variants and are commonly associated with cordierite–quartz intergrowths. The plagioclase–quartz intergrowths display simple, non‐planar interfaces between plagioclase and quartz. Quartz contains (former) fluid inclusions of dimensions similar to those observed in cordierite–quartz intergrowths. The boundary between quartz and enclosing K‐feldspar is cuspate, with quartz cusps penetrating a few tens of nanometres into K‐feldspar, commonly along defects in K‐feldspar and sometimes with very low dihedral angles at their tips. This cuspate microstructure is interpreted as melt pseudomorphs. The plagioclase–quartz intergrowths share some features with myrmekite, but differ in some respects: the composition of the plagioclase (An37Ab62Or1–An38Ab61Or1); the association with cordierite–quartz intergrowths; and microstructures that are atypical of myrmekite (e.g. quartz vermicules shared with cordierite–quartz intergrowths). It is inferred that the plagioclase–quartz intergrowths may have formed from, or in the presence of, melt. Inferred melt‐related microstructures preserved on the nanometre scale suggest that melt on grain boundaries was more pervasive than is evident from light optical and SEM observations.
How Do Intergroup Grievances Develop in the Absence of Oppression? Revolutions and Political Parties in Nineteenth‐Century Uruguay
Authors: Somma Nicolás M.
Published: March 2014

Political sociologists often assume that widespread grievances require a long legacy of intergroup oppression. Yet in nineteenth‐century Uruguay, supporters of the White and Red political parties developed intense grievances against each other even though a legacy of oppression was missing. For explaining this puzzle I present an alternative perspective. It states that grievances first originate among political elites, which mobilize the masses through selective incentives in order to impose their will. If elites and masses are bound by close ties, sustained mobilization facilitates cross‐class group identification and allows grievances to “trickle down” from the top to the bottom of the social structure.
“The Past in the Present:Mills,Tocqueville and the Necessity of History”
Authors: Kumar Krishan
Published: March 2014

Historical sociology has achieved a reasonable degree of respectability in the discipline, and there is much interesting work being produced. But a pronounced aspect of much of this work is an indifference to the question of the value of studying the past as a way to understanding the present. This article argues that, rather than trying to outdo the historians by producing “better,” more theoretically sophisticated history, sociologists would better advance the case for historical sociology by showing how any particular historical study helps illuminate contemporary concerns. The article draws upon the writings ofC.WrightMills andAlexis deTocqueville to show not just the need for historical sociology but also as indications of how this might best be done.
Intergroup Social Exclusion in Childhood: Forms, Norms, Context, and Social Identity
Authors: Bennett Mark
Published: March 2014

Humans are a profoundly social species, aligning with groups, forming group identification, and navigating the social world. One of the complex tasks of childhood is to understand when exclusion is necessary to make groups work well, and when it is wrong, creating unnecessary harm or unfairness. In this volume the authors grapple with many new aspects of exclusion not previously documented by taking a developmental and social psychological approach. The studies reveal original findings regarding how children both perpetuate and are recipients of exclusion, and the processes that accompany these experiences. In reflecting on the diverse range of work represented in this special issue, various themes emerge, such as the roles of context and norms in children's exclusionary behavior and judgment, the particular forms that exclusionary behavior can take, and the consequences that result as part of the developmental process. Most importantly, given that social identities frame a host of phenomena associated with group‐based exclusionary phenomena, the field should reveal the central role that social identity plays in how exclusion and inclusion are understood.
Integrating the Emic (Indigenous) with the Etic (Universal)—A Case of Squaring the Circle or for Adopting a Culture Inclusive Action Theory Perspective
Authors: Eckensberger Lutz H.
Published: March 2014

The dualism of emic and etic plays a crucial role in the emergence of three culturally informed approaches of psychology: cross‐cultural psychology (CCP), cultural psychology (CP) and indigenous psychologies (IPs), a distinction largely accepted nowadays. Similarities and/or differences between these positions are usually discussed either on the level of phenomena (data) or theory. In this paper, however, the discussion takes place on a meta‐theoretical or epistemological level, which is also emerging elsewhere. In following several earlier papers of the author, first, four perspectives are distinguished that underlie present day psychology. Second, these are used as a framework for linking them to the three “camps”. This analysis will show that these perspectives are characterized by different underlying worldviews, interests as well as methodical preferences. Third, it is claimed that this level of discussion is quite fruitful for the ongoing discourse on the three camps, but also helps one to understand, why the duality between emic and etic approaches is—implicitly or explicitly—at the core of these discussions, because their relevance turns out to differ in the three camps. In that sense, the emic/etic duality is used here as a “litmus test” to exemplify these deeper differences between the camps, thereby highlighting them.

Fourth, in order to overcome not only the dilemma between the unique and general in psychology, but also to clarify the relation between the individual and culture it is proposed that psychology should take human action as its unit of analysis, thereby connecting historically to the early beginnings of psychology at the end of the 19th century. It will be argued that a culture inclusive action theory may overcome this tension and may help to integrate western and other indigenous psychologies, and hence it could be advantageous to integrate CP and IPs as well. This is possible because the proposed theory hopefully provides a universal framework for psychological concepts, yet allows for their culture specific expression.
Vegetation, terrain and fire history shape the impact of extreme weather on fire severity and ecosystem response
Authors: Clarke Peter J. , Knox Kirsten J.E. , Bradstock Ross A. , Munoz‐Robles Carlos , Kumar Lalit
Published: March 2014

Questions

Do endogenous (landscape/vegetation) or exogenous (weather) factors control fire severity? During severe fire weather, is there convergence in fire severity across rain forest, forests and heathlands such that all locations burn with similarly high severity? Are there long‐term effects of fire severity in temperate crown‐fire ecosystems?

Location

Montane rain forests, eucalypt forests and heaths in the temperate climate zone of eastern Australia (Washpool/Gibraltar Range National Park).

Methods

The immediate and longer‐term effects of fire weather and landscape (terrain, previous fire history and vegetation type) factors on fire severity and ecosystem response were measured using remote sensing and ground measures of microclimate, productivity and plant resprouting at 45 sites.

Results

Fire weather strongly interacted with terrain, antecedent fire history and vegetation type, resulting in complex mosaics of mixed fire severity rather than convergence to uniform fire severity. Vegetation type influenced the effects of time‐since‐fire and fire frequency on fire severity, suggesting differential fire feedbacks. High fire severity left a long‐term imprint on total reflectance, ground temperatures and productivity of the vegetation, but these effects were not uniform across vegetation types. The abundance of resprouting species was not strongly affected by fire severity.

Conclusions

There was evidence for strong weather control of fire severity but fire history, terrain and vegetation shape the immediate effect due to the contrasting pyrogenic vs pyrophobic nature of the vegetation mosaic. The short‐term dominance of weather as a driver of fire severity is only weakly related to the longer‐term ecosystem response because of the strong resprouting ability of the canopy dominants, even in rain forest. The forest complexes of eastern Australia appear highly resilient to high fire severity in both structure and floristics, which may influence long‐term feedbacks.
No preference in female sika deer for conspecific over heterospecific male sexual calls in a mate choice context
Authors: Wyman M. T. , Locatelli Y. , Charlton B. D. , Reby D.
Published: March 2014

Mating signals can be used both in contexts of species recognition and mate quality assessment. This study examines species recognition abilities in oestrous females presented with male mating calls from both conspecifics and closely related allopatric heterospecifics. Red deer and sika deer are naturally allopatric polygynous species capable of hybridization during sympatry. Male mating calls are sexually selected and differ greatly between species. Previous work indicated that most but not all oestrous red deer hinds prefer male mating calls from conspecifics over heterospecific sika deer. Using two‐speaker playback experiments, we extend this examination by measuring the preference responses of oestrous sika deer hinds to these stimuli. We predicted that oestrous sika deer hinds will show little flexibility in behavioural responses and prefer conspecific calls over heterospecific calls, similar to those of red deer hinds. In contrast, sika deer hinds showed high levels of flexibility and no difference in overall preference behaviours, suggesting that vocal behaviour does not provide a solid barrier to hybridization in this species. The asymmetry in heterospecific preference responses between these species is discussed in relation to possible causation and hybridization patterns observed in free‐ranging populations.
“Here Nobody Holds Your Heart”: Metaphoric and Embodied Emotions of Birth and Displacement among Karen Women in Australia
Authors: Niner Sara , Kokanovic Renata , Cuthbert Denise , Cho Violet
Published: March 2014

Our objective was to explore the ways in which displaced Karen mothers expressed emotions in narrative accounts of motherhood and displacement. We contextualized and analyzed interview data from an ethnographic study of birth and emotions among 15 displaced Karen mothers in Australia. We found that women shared a common symbolic language to describe emotions centered on the heart, which was also associated with heart “problems.” This, along with hypertension, collapsing, or a feeling of surrender were associated responses to extremely adverse events experienced as displaced peoples. A metaphoric schema of emotional terms centered on the heart was connected to embodied expressions of emotion related to illness of the heart. This and other embodied responses were reactions to overwhelming difficulties and fear women endured due to their exposure to political conflict and global inequity.
Navigating and Circumventing a Fragmented Health System: The Patient's Pathway in the Sierra Madre Region of Chiapas, Mexico
Authors: Molina Rose Leonard , Palazuelos Daniel
Published: March 2014

Mexico has implemented several important reforms in how health care for its poorest is financed and delivered. Seguro Popular, in particular, a recently implemented social insurance program, aims to provide new funds for a previously underfunded state‐based safety net system. Through in‐depth ethnographic structured interviews with impoverished farmers in the state of Chiapas, this article presents an analysis of Seguro Popular from the perspective of a highly underserved beneficiary group. Specific points of tension among the various stakeholders—the government system (including public clinics, hospitals, and vertical programs), community members, private doctors, and pharmacies—are highlighted and discussed. Ethnographic data presented in this article expose distinct gaps between national health policy rhetoric and the reality of access to health services at the community level in a highly marginalized municipality in one of Mexico's poorest states. These insights have important implications for the structure and implementation of on‐going reforms.
Theological Instruction and Faith Transmission: Lonergan's Method as
Pedagogy Theology
Authors: Sullivan Patricia A.
Published: March 2014

Hans Urs Von Balthasar's lament that coincidence of the theologian and
the saint has not been the norm since the Middle Ages can be emblematic of a
methodological issue impacting both academic theology and the Church wholly
by separation of that which as a faith tenet should be unified—word and
witness. Theologians’ intent today to speak from but not be confused with
their location, the theological discipline's reach for respectability in an
increasingly secular academy, market forces deliberately shrinking
theology's influence except in such as interdisciplinary endeavors
supporting other publics’ aims, the contemporary narrow specialization of
the theologian, and the sometime view that narrow tasks serving theology are
theology itself all result in conflations of theology and religion. So
“theology” and “spirituality,” as Balthasar identified the breach, will be
separate. Yet we hope that theologians, with all others, will be saints.
Does this not, particularly to students, transmit the faith? Although
Bernard Lonergan's method might seem to exacerbate the separation given its
numerous theological specialties and conversion types, it also offers the
way of reunification—without threat to academic integrity. The theological
method, with its turn to the subject, can ground a theology (and method) of
pedagogy.
Gastrointestinal morbidity in obesity
Authors: Acosta Andres , Camilleri Michael
Published: March 2014

Obesity is a complex disease that results from increased energy intake and decreased energy expenditure. The gastrointestinal system plays a key role in the pathogenesis of obesity and facilitates caloric imbalance. Changes in gastrointestinal hormones and the inhibition of mechanisms that curtail caloric intake result in weight gain. It is not clear if the gastrointestinal role in obesity is a cause or an effect of this disease. Obesity is often associated with type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Obesity is also associated with gastrointestinal disorders, which are more frequent and present earlier than T2DM and CVD. Diseases such as gastroesophageal reflux disease (GERD), cholelithiasis, or nonalcoholic steatohepatitis are directly related to body weight and abdominal adiposity. Our objective is to assess the role of each gastrointestinal organ in obesity and the gastrointestinal morbidity resulting in those organs from the effects of obesity.
Testing metapopulation concepts: effects of patch characteristics and neighborhood occupancy on the dynamics of an endangered lagomorph
Authors: Eaton Mitchell J. , Hughes Phillip T. , Hines James E. , Nichols James D.
Published: March 2014

Metapopulation ecology is a field that is richer in theory than in empirical results. Many existing empirical studies use an incidence function approach based on spatial patterns and key assumptions about extinction and colonization rates. Here we recast these assumptions as hypotheses to be tested using 18 years of historic detection survey data combined with four years of data from a new monitoring program for the Lower Keys marsh rabbit. We developed a new model to estimate probabilities of local extinction and colonization in the presence of nondetection, while accounting for estimated occupancy levels of neighboring patches. We used model selection to identify important drivers of population turnover and estimate the effective neighborhood size for this system. Several key relationships related to patch size and isolation that are often assumed in metapopulation models were supported: patch size was negatively related to the probability of extinction and positively related to colonization, and estimated occupancy of neighboring patches was positively related to colonization and negatively related to extinction probabilities. This latter relationship suggested the existence of rescue effects. In our study system, we inferred that coastal patches experienced higher probabilities of extinction and colonization than interior patches. Interior patches exhibited higher occupancy probabilities and may serve as refugia, permitting colonization of coastal patches following disturbances such as hurricanes and storm surges. Our modeling approach should be useful for incorporating neighbor occupancy into future metapopulation analyses and in dealing with other historic occupancy surveys that may not include the recommended levels of sampling replication.
Minoxidil 5% Solution for Topical Treatment of Loose Anagen Hair Syndrome
Authors: Chandran Nisha S. , Oranje Arnold P.
Published: March 2014

A 2‐year‐old girl with a diagnosis of loose anagen hair syndrome was treated with a tapering regime of minoxidil 5% solution over 28 months, resulting in quick, significant clinical improvement with no adverse effects.
Nickel Allergy—A Potential Cause of Razor Dermatitis
Authors: Admani Shehla , Matiz Catalina , Jacob Sharon E.
Published: March 2014

We discuss a case of razor‐associated dermatitis to highlight a potential source of nickel exposure in allergic patients.
Leukemia Cutis and Facial Nerve Palsy as Presenting Symptoms of Acute Lymphoblastic Leukemia
Authors: Gold Heidi L. , Grynspan David , Kanigsberg Nordau
Published: March 2014

Leukemia cutis and facial nerve palsy are rare presenting symptoms of leukemia. This report describes a case of acute T‐cell lymphoblastic leukemia (ALL) presenting with only these two symptoms, a presentation of ALL that, to our knowledge, has not been previously described. It serves to alert physicians to look for underlying malignancy in the setting of cutaneous findings associated with facial nerve palsy.
Vemurafenib‐Induced Neutrophilic Panniculitis in a Child with a Brainstem Glioma
Authors: West Emily S. , Williams Victoria L. , Morelli Joseph G.
Published: March 2014

Neutrophilic panniculitis is a rare adverse effect of therapy with selective BRAF inhibitors. We report a case of neutrophilic panniculitis in a 15‐year‐old girl receiving treatment with vemurafenib for a brainstem glioma. Clinicians should be aware of this rare but important side effect of vemurafenib. This is the first report of neutrophilic panniculitis in a child treated with vemurafenib.
Attention interference for emotional stimuli in cardiac interoceptive awareness
Authors: Werner Natalie S. , Mannhart Tanja , Reyes Del Paso Gustavo A. , Duschek Stefan
Published: March 2014

Previous research has shown that individuals with good perception of cardiac signals, referred to as cardiac interoceptive awareness, experience emotions more intensely. To investigate if emotional experience in high cardiac interoceptive awareness arises from biases in attention, we compared the performance of participants with high versus regular cardiac interoceptive awareness in an emotional Stroop task. Participants with high cardiac interoceptive awareness showed attention interference for negative words, whereas participants with regular cardiac interoceptive awareness showed attention facilitation for positive words. Our data provide further evidence for the emotion information process associated with cardiac interoceptive awareness. The results support the notion that better access to cardiac changes accompanying negative emotional conditions results in automatic vigilance for negative information and may interfere with cognitive processing.
Validity of the Weakly Nonlinear Solution of the Cauchy Problem for the Boussinesq‐Type Equation
Authors: Khusnutdinova K. R. , Moore K. R. , Pelinovsky D. E.
Published: March 2014

We consider the initial‐value problem for the regularized Boussinesq‐type equation in the class of periodic functions. Validity of the weakly nonlinear solution, given in terms of two counterpropagating waves satisfying the uncoupled Ostrovsky equations, is examined. We prove analytically and illustrate numerically that the improved accuracy of the solution can be achieved at the timescales of the Ostrovsky equation if solutions of the linearized Ostrovsky equations are incorporated into the asymptotic solution. Compared to the previous literature, we show that the approximation error can be controlled in the energy space of periodic functions and the nonzero mean values of the periodic functions can be naturally incorporated in the justification analysis.
A cross‐cultural comparison of verbal learning and memory functions in reading disabled American and Norwegian adolescents
Authors: Asbjørnsen Arve E. , Obrzut John E. , Oyler James D.
Published: March 2014

The present study reports the results of a cross‐cultural analysis of the role of phonetic and semantic cues in verbal learning and memory. A newly developed memory test procedure, the Bergen‐Tucson Verbal Learning Test (BTVLT), expands earlier test procedures as phonetic cues are applied in addition to semantic cues in a cued recall procedure. Samples of reading disabled and typically developed adolescents from the US and from Norway were recruited as voluntary participants. The results indicate that the stimulus materials chosen for the memory test are working well in both American and in Norwegian samples, yielding acquisition results comparable to similar list learning procedures, and also yielding high internal consistency across learning trials. The procedure also reliably differentiates between reading disabled samples in both languages, and also yields cross‐cultural differences that seem to reflect differences in transparency and differences in the orthography of the included languages. The BTVLT with its focus on phonetic coding is a promising supplement to established tests of verbal memory for assessment of reading and language impaired individuals.
Being responsible versus acting responsibly: Effects of agency and risk taking on responsibility judgments
Authors: Nordbye Gro Hege Haraldsen , Teigen Karl Halvor
Published: March 2014

In three experimental studies, with managers and students as participants, we explore in this paper the relation between two kinds of responsibility judgments, called Responsibility 1 (R1) and Responsibility 2 (R2). Decision makers can be viewed as being more or less responsible for their choice and its consequences (R1). Their actions can also be evaluated, from a normative point of view, as instances of more or less responsible behavior (R2). Experiment 1 showed that managers who depart from the default or “normal” course of action, by choosing a new (versus familiar) alternative, changing (versus sticking to) an initial decision, or going against (versus following) the advice of a management team, are rated as more responsible (R1) for the outcomes of their decision. At the same time, they are perceived toactin a less responsible way (R2). Experiment 2 compared decision makers choosing between more or less risky options. High risk takers were held more responsible (R1) for their choice and for its consequences, but were again viewed as behaving in a less responsible way (R2) than low risk takers. In Experiment 3, participants judged decision makers who followed or opposed others' advice by choosing either a high or a low risk option. Opposing others' advice led to higher R1 and lower R2 scores, especially when choosing the high risk option, moderated by outcome (successful decisions appearing more responsible than those that went wrong). Thus R1 and R2 judgments should be distinguished as having different and sometimes even opposite determinants.
A Moral Hazard Approach to Wage Discounts under Informal Hiring
Authors: Duran Miguel A. , Morales Antonio J.
Published: March 2014

This study discusses informal hiring in terms of a standard principal–agent model. We have developed an adverse selection model of the labour market where effort is not contractible and employers have the opportunity to use informal search channels for hiring purposes. This standard framework enables us to provide an effort‐based explanation of the wage gap associated with informal hiring. Besides the wage discount, another feature of the equilibrium is that low‐ability workers informally hired shirk.
Feasibility, Stability, and Multiple Research Joint Ventures
Authors: Yao Zhiyong , Zheng Bingyong
Published: March 2014

We study multiple research joint ventures (RJVs) using a repeated game with imperfect monitoring. Compared with the single joint venture case, we show that cooperation in multiple joint ventures creates two advantages for participating firms. First, by linking decisions together across all joint ventures firms can mitigate the likelihood of cooperation breakdowns following bad R&D outcomes. Second, as the incentive cost to sustain cooperation is independent of the number of joint ventures, the economy of scale effect reduces the efficiency loss due to imperfect monitoring.
Sunday School Teacher, Culture Warrior: The Politics of Lay Leaders in Three Religious Traditions*
Authors: Bean Lydia , Martinez Brandon C.
Published: March 2014

Objectives

Political theorists have praised civic organizations as spaces for open political deliberation. But their leadership structure privileges some voices over others. In congregations, clergy set the context for political discussion. We argue that volunteer religious leaders also shape political talk in local churches. Lay leaders serve as political opinion leaders within local churches, with the power to either deepen or bridge political polarization over religion and morality.

Methods

We compare lay leaders across three religious traditions, using a unique measure from the 2005 Baylor Religion Survey.

Results

Lay leaders in evangelical, mainline, and Catholic traditions are more politically active than other attenders, but evangelical lay leaders are also more morally conservative than others in their tradition. Comparing across traditions, we argue that evangelical lay leaders foster greater political cohesion within their tradition.

Conclusion

We identify voluntary group leadership as a mechanism that allows civic organizations to generate political presence.
Nucleus Implantation: The Biomechanics of Augmentation Versus Replacement With Varying Degrees of Nucleotomy
Authors: Cannella Marco , Isaacs Jessica L. , Allen Shanee , Orana Argjenta , Vresilovic Edward , Marcolongo Michele
Published: March 2014

Nucleus pulposus replacement and augmentation has been proposed to restore disk mechanics in early stages of degeneration with the option of providing a minimally invasive procedure for pain relief to patients with an earlier stage of degeneration. The goal of this paper is to examine compressive stability of the intervertebral disk after either partial nucleus replacement or nuclear augmentation in the absence of denucleation. Thirteen human cadaver lumbar anterior column units were used to study the effects of denucleation and augmentation on the compressive mechanical behavior of the human intervertebral disk. Testing was performed in axial compression after incremental steps of partial denucleation and subsequent implantation of a synthetic hydrogel nucleus replacement. In a separate set of experiments, the disks were not denucleated but augmented with the same synthetic hydrogel nucleus replacement. Neutral zone, range of motion, and stiffness were measured. The results showed that compressive stabilization of the disk can be re-established with nucleus replacement even for partial denucleation. Augmentation of the disk resulted in an increase in disk height and intradiskal pressure that were linearly related to the volume of polymer implanted. Intervertebral disk instability, evidenced by increased neutral zone and ranges of motion, associated with degeneration can be restored by volume filling of the nucleus pulposus using the hydrogel device presented here.
A Method for Selecting Velocity Filter Cutoff Frequency for Maximizing Impedance Width Performance in Haptic Interfaces
Authors: Chawda Vinay , Celik Ozkan , O’Malley Marcia K.
Published: March 2014

This paper analyzes the effect of velocity filtering cut-off frequency on the Z-width performance in haptic interfaces. Finite Difference Method (FDM) cascaded with a lowpass filter is the most commonly used technique for estimating velocity from position data in haptic interfaces. So far, there is no prescribed method for obtaining the FDM+filter cut-off frequency that will maximize the Z-width performance. We present a simulation based method to demonstrate that there exists such an ideal FDM+filter cut-off frequency, and that it can be predicted by numerical simulation. Experiments are conducted on a single degree-of-freedom linear haptic interface to validate the simulation results.
Robust Control of Switched Linear Systems via Min of Quadratics
Authors: Yuan Chengzhi , Wu Fen
Published: March 2014

In this paper, we will investigate the robust switching control problem for switched linear systems by using a class of composite quadratic functions, the min (of quadratics) function, to improve performance and enhance control design flexibility. The robustness is reflected in two prospectives including the ℋ ∞ performance and arbitrary switching of subsystems. A hysteresis min-switching strategy is employed to orchestrate the switching among a collection of controllers. The synthesis conditions for both state feedback and output feedback control problems are derived in terms of a set of linear matrix inequalities (LMIs) with linear search over scalar variables. The proposed min function based approach unifies the existing single Lyapunov function based method and multiple Lyapunov function based method in a general framework, and the derived LMI conditions cover the existing LMI conditions as special cases. Numerical studies are included to demonstrate the advantages of the proposed control design approach.
Multi-Input Observer for Estimation of Compressor Flow
Authors: Kalabić Uroš , Kolmanovsky Ilya , Buckland Julia
Published: March 2014

This paper presents a formulation and an application of a high-gain multi-input observer to estimate the compressor flow in turbocharged gasoline engines. Such an observer is desired in vehicles lacking a mass air flow sensor yet in which compressor flow needs to be known; for instance, it is desired in order to apply a reference governor for surge constraint avoidance. In this application, a fast estimate of the compressor flow is required so that the reference governor can take action before the compressor goes into surge. The multi-input observer uses pressure measurements and cylinder flow to estimate the compressor flow. This paper presents the derivation of the observer and both simulation and experimental results showing its feasibility in estimating the compressor flow.
Impedance Reduction Controller Design for Mechanical Systems
Authors: Woo Hanseung , Kong Kyoungchul
Published: March 2014

Safety is one of important factors in control of mechatronic systems interacting with humans. In order to evaluate the safety of such systems, mechanical impedance is often utilized as it indicates the magnitude of reaction forces when the systems are subjected to motions. Namely, the mechatronic systems should have low mechanical impedance for improved safety. In this paper, a methodology to design controllers for reduction of mechanical impedance is proposed. For the proposed controller design, the mathematical definition of the mechanical impedance for open-loop and closed-loop systems is introduced. Then the controllers are designed for stable and unstable systems such that they effectively lower the magnitude of mechanical impedance with guaranteed stability. The proposed method is verified through case studies including simulations.
Real-Time Battery Model Identification Using a Two Time-Scaled Approach
Authors: Hu Yiran , Wang Yue-Yun
Published: March 2014

Battery state estimation (BSE) is one of the most important design aspects of an electrified propulsion system. It includes important functions such as state-of-charge estimation which is essentially for the energy management system. A successful and practical approach to battery state estimation is via real time battery model parameter identification. In this approach, a low-order control-oriented model is used to approximate the battery dynamics. Then a recursive least squares is used to identify the model parameters in real time. Despite its good properties, this approach can fail to identify the optimal model parameters if the underlying system contains time constants that are very far apart in terms of time-scale. Unfortunately this is the case for typical lithium-ion batteries especially at lower temperatures. In this paper, a modified battery model parameter identification method is proposed where the slower and faster battery dynamics are identified separately. The battery impedance information is used to guide how to separate the slower and faster dynamics, though not used specifically in the identification algorithm. This modified algorithm is still based on least squares and can be implemented in real time using recursive least squares. Laboratory data is used to demonstrate the validity of this method.
Dynamic Modeling of a Compliant Tail-Propelled Robotic Fish
Authors: Kopman Vladislav , Laut Jeffrey , Porfiri Maurizio , Acquaviva Francesco , Rizzo Alessandro
Published: March 2014

This paper presents a dynamic model for a class of robotic fish propelled by a tail with a flexible fin. The robot is comprised of a rigid frontal link acting as a body and a rear link serving as the tail. The tail includes a rigid component, hinged to the body through a servomotor, which is connected to a compliant caudal fin whose underwater vibration induces the propulsion. The robot’s body dynamics is modeled using Kirchhoff’s equations of motion of bodies in quiescent fluids, while its tail motion is described with Euler-Bernoulli beam theory, accounting for the effect of the encompassing fluid through the Morison equation. Simulation data of the model is compared with experimental data. Applications of the model include simulation, prediction, design optimization, and control.
Control Design for Cancellation of Unnatural Reaction Torque and Vibrations in Variable-Gear-Ratio Steering System
Authors: Oshima Atsushi , Chen Xu , Sugita Sumio , Tomizuka Masayoshi
Published: March 2014

Variable-gear-ratio steering is an advanced feature in automotive vehicles. As the name suggest, it changes the steering gear ratio depending on the speed of the vehicle. This feature can simplify steering for the driver, which leads to various advantages, such as improved vehicle comfort, stability, and safety. One serious problem, however, is that the variable-gear-ratio system generates unnatural torque to the driver whenever the variable-gear-ratio control is activated. Such unnatural torque includes both low-frequency and steering-speed-dependent components. This paper proposes a control method to cancel this unnatural torque. We address the problem by using a tire sensor and a set of feedback and feedforward algorithms. Effectiveness of the proposed method is experimentally verified using a hardware-in-the-loop experimental setup. Stability and robustness under model uncertainties are evaluated.
The Application of Electrode Design in Vibrating Piezoceramic Plate for Energy Harvesting System
Authors: Huang Yu-Hsi , Chao Ching-Kong , Chou Wan-Ting
Published: March 2014

The energy harvesting system of piezoceramic plate is studied on the electrode configuration to improve the electromechanical transferring efficiency. The piezoceramic plate is used to perform the vibration characteristics by experimental measurements and finite element method (FEM). Thereafter, the dynamic characteristics and the electromechanical coupling efficiency of the piezoelectric energy harvesting system are studied by the electrode design method of the piezoceramic plate. Several experimental techniques are used to measure the dynamic characteristics of piezoceramic plate. First, the full-filed optical technique, amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI), can measure simultaneously the resonant frequencies and mode shapes for out-of-plane and in-plane vibrations. Second, the pointwisely measuring system, laser Doppler vibrometer (LDV), can obtain resonant frequencies by dynamic signal swept-sine analysis. Third, the correspondent in-plane resonant frequencies and anti-resonant frequencies are obtained by impedance analysis. The experimental results of vibration characteristics are verified with numerical calculations. Besides the dynamic characteristics of piezoceramic plates are analyzed in converse piezoelectric effect, the direct piezoelectric effect of piezoceramic plates are excited by shaker to generate the electric voltage. It has excellent consistence between resonant frequencies and mode shapes on the vibration characteristics by experimental measurements and finite element numerical calculations. In this study, the Electrical Potential Gradient (EPG) calculated by FEM is proposed to evaluate the electromechanical coupling efficiency of piezoceramic plate on the specific vibration mode. The correspondent electrode configuration, which is designed by EPG, can produce the best electromechanical transfer both in direct and converse piezoelectric effects. It is concluded that the vibration characteristics of piezoelectric materials have excellent consistence determined by experimental measurements and FEM.
Nonlinear Models for Optimal Placement of Magnetically-Actuated Cilium
Authors: Banka Nathan , Devasia Santosh
Published: March 2014

Artificial cilia systems are used for microfluidic manipulation. By analogy to the biological cilia, such systems seek to mix, separate, or propel fluids, particularly in the low-Reynolds-number regime, without damaging sensitive samples. An important category of artificial cilia systems is magnetically-actuated artificial cilia, since the driving magnetic field does not interact with many samples of interest. Simulation results are presented to show that linear modeling fails to adequately predict the optimal location due to strong nonlinear effects; using the linear result to select magnet placement results in amplitudes 84% lower than the amplitude with the optimal placement found using the nonlinear model. This represents a substantial loss in efficacy. Since large amplitudes are desirable to enhance flow manipulation, the results illustrate the importance of nonlinear dynamics models in the design of magnet-cilia devices.
Modeling Heterogeneous Populations of Thermostatically Controlled Loads Using Diffusion-Advection PDEs
Authors: Moura Scott , Ruiz Victor , Bendsten Jan
Published: March 2014

This paper focuses on developing a partial differential equation (PDE)-based model and parameter identification scheme for heterogeneous populations of thermostatically controlled loads (TCLs). First, a coupled two-state hyperbolic PDE model for homogenous TCL populations is derived. This model is extended to heterogeneous populations by including a diffusive term, which provides an elegant PDE control-oriented model. Second, a novel parameter identification scheme is derived for the PDE model structure, which utilizes only boundary measurements and aggregated power measurements. Simulation results against a Monte Carlo model of a large TCL population demonstrate the usefulness of the approach. The proposed model and parameter identification scheme provide system critical information for advanced demand side management control systems.
Study on the Vibration Response of Axially Moving Continua
Authors: Chung Chunhui , Kao Imin
Published: March 2014

Axially moving continua such as belt, chain, and conveyer are common transmission components. The study of the vibration response of axially moving continua is an essential topic to understand the fundamentals of vibration and improve the performance of the machines. However, it typically requires more rigorous effort in mathematical derivation to obtain the analytical forced vibration responses of the axially moving continua because of the characteristics of non-self-adjoint equation of motion. The methods utilized to obtain the analytical solutions include the modal analysis, canonical form, wave propagation, Laplace transform, and transfer function. In this review paper, these methods will be reviewed and presented. The advantages and disadvantages of different methodologies are discussed as well.
Preserving Stability Under Communication Delays in Multi Agent Systems
Authors: Rastgoftar Hossein , Jayasuriya Suhada
Published: March 2014

The effect of time delays on the stability of a recently proposed continuum approach for controlling a multi agent system (MAS) evolving in n-D under a special local inter-agent communication protocol is considered. There a homogenous map determined by n+1 leaders is learned by the follower agents each communicating with n+1 adjacent agents. In this work both position and velocity information of adjacent agents are used for local control of follower agents whereas in previous work [1, 2] only position information of adjacent agents was used. Stability of the proposed method under a time delay h is studied using the cluster treatment of characteristic roots (CTCR) [3]. It is shown that the stability of MAS evolution can be preserved when (i) the velocity of any follower agent is updated using both position and velocity of its adjacent agents at time (t-h); and (ii) the communication matrix has real eigenvalues. In addition, it is shown that when there is no communication delay, deviations from a selected homogenous map during transients may be minimized by updating only the position of a follower using both position and velocity of its adjacent agents.
A Validated System-Level Thermodynamic Model of a Reciprocating Compressor With Application to Valve Condition Monitoring
Authors: Kolodziej Jason R. , Guerra Christopher J.
Published: March 2014

Condition-based health monitoring systems are a very important addition to machinery to monitor the system and assure it is running at the peak efficiency, to schedule maintenance, and prevent catastrophic failure. Recently, these systems have become more common on industrial compression technology. Reciprocating compressor health monitoring systems typically use only indirect measurements, P-V diagrams, to monitor the system’s health.

Specifically, this research focuses on three different valve failure modes that are common in reciprocating compressors: liquid slugging; valve spring fatigue; and valve seat wear. First, a system-level model of a Dresser-Rand industrial reciprocating compressor is derived and validated, experimentally, to better understand how different subsystem dynamics are related through the compressor. Also, a preliminary instrument investigation is conducted to determine what sensor types are the most effective at detecting these faults.
Development of an Advanced Model of Passive Dynamic Biped Walking
Authors: Koop Derek , Wu Christine Q.
Published: March 2014

Passive dynamic walking is a manner of walking developed, partially or in whole, by the energy provided by gravity. Studying passive dynamic walking provides insight into human walking and is an invaluable tool for designing energy efficient biped robots. The objective of this research was to develop a continuous mathematical model of passive dynamic walking, in which the Hunt-Crossley contact model and the LuGre friction model were used to represent the normal and tangential ground reactions. A physical passive walker was built to validate the proposed mathematical model. A traditional impact-based passive walking model was also used as a reference to demonstrate the advancement of the proposed passive dynamic walking model. The simulated gait of the proposed model matched the gait of the physical passive walker exceptionally well, both in trend and magnitude.