bluuebunny/crossref_metadata_2025 huggingface dataset:
Prospects and limitations of treatment with botulinum neurotoxin type A for patients with refractory idiopathic detrusor overactivity
Authors: Schmid D.M. , Roy S. , Sulser T. , Scheiner D.
Published: July 2008

In this review we summarize the recent innovation of botulinum‐A neurotoxin (BoNT‐A) injections in the bladder as a potential new treatment option for idiopathic detrusor overactivity, refractory to conventional anticholinergic medication. BoNT‐A is produced by Clostridium botulinum and consists of a 150‐kDa neurotoxic protein that has the ability to cleave proteins within the nerve terminal. BoNT‐A is thereby able to prevent acetylcholine release at the presynaptic membrane, resulting in a chemodenervation of the detrusor muscle after intravesical injection; this can reduce symptoms in patients with refractory idiopathic detrusor overactivity. BoNT‐A intradetrusor injections might be an alternative to invasive surgery for patients in whom conservative measures and anticholinergic treatment have failed. Clinical studies with different dosages and injection protocols show success rates of 60–96% for neurogenic and non‐neurogenic detrusor overactivity, with wide variations in the duration of response. The drug is still under development for the indication of idiopathic detrusor overactivity, and is under ongoing investigation for long‐term efficacy and safety.
Engineered native pathways for high kaempferol and caffeoylquinate production in potato
Authors: Rommens Caius M. , Richael Craig M. , Yan Hua , Navarre Duroy A. , Ye Jingsong , Krucker Michele , Swords Kathy
Published: July 2008

Flavonols and caffeoylquinates represent important groups of phenolic antioxidants with health‐promoting activities. The genetic potential of potato (Solanum tuberosum) to produce high levels of these dietary compounds has not been realized in currently available commodity varieties. In this article, it is demonstrated that tuber‐specific expression of the native and slightly modified MYB transcription factor gene StMtf1M activates the phenylpropanoid biosynthetic pathway. Compared with untransformed controls, transgenic tubers contained fourfold increased levels of caffeoylquinates, including chlorogenic acid (CGA) (1.80 mg/g dry weight), whilst also accumulating various flavonols and anthocyanins. Subsequent impairment of anthocyanin biosynthesis through silencing of the flavonoid‐3′,5′‐hydroxylase (F3′5′h) gene resulted in the accumulation of kaempferol‐rut (KAR) to levels that were approximately 100‐fold higher than in controls (0.12 mg/g dry weight). The biochemical changes were associated with increased expression of both the CGA biosynthetic hydroxycinnamoyl‐CoA quinate hydroxycinnamoyl transferase (Hqt) gene and the upstream chorismate mutase (Cm) and prephenate dehydratase (Pdh) genes. Field trials indicated that transgenic lines produced similar tuber yields to the original potato variety Bintje. Processed products of these lines retained most of their phenylpropanoids and were indistinguishable from untransformed controls in texture and taste.
The ILO: An Agency for Globalization?
Authors: Standing Guy
Published: July 2008

The International Labour Organization, set up in 1919 to develop and promote labour standards, is at a crucial point. It has preached that labour is not a commodity and in 1969 received the Nobel Peace Prize. Since then it has run into trouble. This article considers how the ILO has failed to come to terms with the Global Transformation, seeing it as trying to play three roles — a standard‐setter, a technical assistance agency and a knowledge generator — without developing the professional capacity to do so. The big question is whether the ILO could become an effective development agency given the changing character of work and labour in globalizing labour markets and its antiquated governance structure.
The Rise and Rise of Ecofeminism as a Development Fable: A Response to Melissa Leach's ‘Earth Mothers and Other Ecofeminist Fables: How a Strategic Notion Rose and Fell’
Authors: Moore Niamh
Published: July 2008

This contribution offers a response to Melissa Leach's paper ‘Earth Mothers and Other Ecofeminist Fables: How a Strategic Notion Rose and Fell’, published in an earlier issue of Development and Change. Leach's article examined the rise and fall of the figure of ‘woman as natural environmental carer’ in environment and development discourses. Specifically, it appeared concerned with the role of ‘the northern ecofeminist’ in popularizing this figure, and the notion that women have a special relationship with the environment. This response points to the reliance on the figure of the ‘northern ecofeminist’ as a foil to gender and development (GAD) discourses, and situates this anxiety over the figure of ‘woman as natural environmental carer’ in the context of some key feminist debates of the 1990s. Conflicts between GAD scholars and ecofeminists can be understood as one manifestation of tensions over essentialism in feminism. Attending to how conflicts over essentialism have been worked through in feminism could productively inform efforts to think through the nexus of gender, environment and development.
Non‐Market Institutions in Economic Development: The Role of the Third Sector
Authors: Valentinov Vladislav
Published: July 2008

In an article published in this journal in 2005, Dorward et al. argued that non‐market institutions are particularly effective in addressing market failures in the high‐transaction cost institutional environment which is often characteristic of low‐income countries. This comment develops additional theoretical underpinnings of this argument by exploring differences in the capacity for addressing market failure of for‐profit firms, on the one hand, and third sector organizations representing a major type of non‐market institutions, on the other. It is argued that while for‐profit firms address market failures by facilitating market exchange, third sector organizations do so by replacing exchange with self‐sufficiency. This recourse to self‐sufficiency is reflected in the important role of third sector organizations in economic development in low‐income countries.
Rewards and Costs in Adolescent Other‐sex Friendships: Comparisons to Same‐sex Friendships and Romantic Relationships
Authors: Hand Laura Shaffer , Furman Wyndol
Published: July 2008

This study used a social exchange framework to examine the features of non‐romantic other‐sex (OS) friendships compared with same‐sex (SS) friendships and romantic relationships. High school seniors (N = 141) completed open‐ended interviews about the benefits and costs of having OS friendships, SS friendships, and romantic relationships in general. As expected, perspective taking, learning about the other sex, and meeting the other sex were seen as rewards of OS friendships more often than for SS friendships and romantic relationships. Confusion about the nature of the relationship was seen as a cost of OS friendships more often than of SS friendships and romantic relationships. Intimacy, support, and companionship were mentioned less often as rewards of OS friendships than romantic relationships. Adolescents also completed questionnaires about their own specific relationships of each type. Their OS friendships were perceived as less supportive than their other two relationships; OS friendships were also seen as having fewer negative interactions than romantic relationships. Our findings expand the application of social exchange theory and lend empirical support to prior speculations about OS friendships and their importance in adolescents' social worlds.
MODELING SPATIAL AUTOCORRELATION IN SPATIAL INTERACTION DATA: AN APPLICATION TO PATENT CITATION DATA IN THE EUROPEAN UNION*
Authors: Fischer Manfred M. , Griffith Daniel A.
Published: July 2008

ABSTRACTSpatial interaction models of the gravity type are widely used to model origin–destination flows. They draw attention to three types of variables to explain variation in spatial interactions across geographic space: variables that characterize an origin region of a flow, variables that characterize a destination region of a flow, and finally variables that measure the separation between origin and destination regions. This paper outlines and compares two approaches, the spatial econometric and the eigenfunction‐based spatial filtering approach, to deal with the issue of spatial autocorrelation among flow residuals. An example using patent citation data that capture knowledge flows across 112 European regions serves to illustrate the application and the comparison of the two approaches.
PREFERENCE HETEROGENEITY AND ECONOMIC GEOGRAPHY*
Authors: Nocco Antonella
Published: July 2008

ABSTRACT We investigate the effect of preference heterogeneity between skilled and unskilled workers on agglomeration, and we identify a new source of dependence of equilibrium prices on the demand properties shaped by the inter‐regional distribution of workers. We find a new preference effect, and we show that when the intensity of skilled workers' preference for the modern good and its variety is strong enough, prices charged by firms may even increase when the mass of local firms increases, therefore acting as a new dispersion force when trade costs are low or as a new agglomeration force when trade costs are high.
FRAGMENTATION AND CLUSTERING IN VERTICALLY LINKED INDUSTRIES*
Authors: Pais Joana , Pedro Pontes José
Published: July 2008

ABSTRACT This paper models the location of two vertically related firms in a low labor cost country and in a country with a large market. The upstream industry is more labor intensive than the downstream industry. We find that spatial fragmentation occurs for low values of the input‐output coefficient and intermediate values of the transport rate, particularly if the countries are very asymmetric in size. Otherwise, we obtain agglomeration either in the low cost country (when the transport rate is low) or in the large market (when the transport rate is high). Multiple agglomerated equilibria arise when the transport cost of the intermediate good is significant.
‘We are nurses, we are supposed to care for people’: professional values among nurses in NHS Direct call centres
Authors: Mueller Frank , Valsecchi Raffaella , Smith Chris , Gabe Jonathan , Elston Mary Ann
Published: July 2008

This paper explores the interpretive negotiation of professional values by nurses working in a large public‐sector organisation in the UK, namely the NHS Direct (NHSD). Reported are findings from a number of case studies of NHSD, undertaken in response to calls for more research into so‐called professional call centre settings.
Is the Relationship between Inflation and Its Uncertainty Linear?
Authors: Karanasos Menelaos , Schurer Stefanie
Published: July 2008

We use parametric power ARCH models of the conditional variance of inflation to model the relationship between inflation and its uncertainty using monthly data for Germany, the Netherlands and Sweden over a period ranging from 1962 to 2004. For all three countries inflation significantly raises inflation uncertainty as predicted by Friedman. Increased uncertainty affects inflation in all countries but not in the same manner. For Sweden we find a negative impact in accordance with the Holland hypothesis, whereas for Germany and the Netherlands we find the opposite in support of the Cukierman-Meltzer hypothesis. In a sensitivity analysis we show that an arbitrary choice of the heteroscedasticity parameter influences this relationship significantly.
Transatlantic Differences in Labour Markets: Changes in Wage and Non-Employment Structures in the 1980s and the 1990s
Authors: Puhani Patrick A.
Published: July 2008

Rising wage inequality in the United States and Britain and rising continental European unemployment have led to a popular view in the economics profession that these two phenomena are related to negative relative demand shocks against the unskilled, combined with flexible wages in the Anglo-Saxon countries, but wage rigidities in continental Europe (‘Krugman hypothesis’). This paper tests this hypothesis based on seven large person-level data sets for the 1980s and the 1990s. I use a more sophisticated categorization of low-skilled workers than previous studies, which exhibits differences between German workers with and without apprenticeship training, particularly in the 1980s. I find evidence for the Krugman hypothesis when Germany is compared with the United States. However, supply changes differ considerably between countries, with Britain experiencing enormous increases in skill supply explaining the relatively constant British skill premium in the 1990s.
Ruffed GrouseBonasa umbellushabitat selection in a spatially complex forest: evidence for spatial constraints on patch selection
Authors: ZIMMERMAN GUTHRIE S. , GUTIÉRREZ R. J.
Published: July 2008

Drumming display sites of male Ruffed GrouseBonasa umbellusserve as activity centres and occur in a variety of forest types and age classes. We used a case‐control study design and model selection to evaluate a set of predictions about habitat constraints placed upon Grouse given the habitat where their breeding season activity centres were located. We located 110 individual Grouse activity centres near Cloquet, Minnesota, between 2002 and 2005, and 40 activity centres at two other sites in northern Minnesota in 2005. Our most parsimonious model indicated that Ruffed Grouse used logs more than other potential drumming structures (e.g. stumps, dirt mounds or roots) and sites with a higher density of shrubs as compared with unused sites. Predicted values from this model correlated with observed values from independently sampled areas. Structures used by Grouse for their drumming display were characterized by a greater density of aspen stems than unused sites when in young aspen and mature pine, but not when in other forest types. The patterns of habitat selection that we observed supported predictions (1) that the differences in habitats at larger spatial scales (e.g. forest stands or breeding territories) may impose certain constraints on specific sites selected for their drumming display, and (2) that some of these constraints may vary by forest type.
Polyphyly of the genus Apalis and a new generic name for the species pulchra and ruwenzorii
Authors: NGUEMBOCK BILLY , FJELDSÅ JON , COULOUX ARNAUD , CRUAUD CORINNE , PASQUET ERIC
Published: July 2008

The genus Apalis is a member of the African forest warblers clade of the Cisticolidae. In view of its morphological diversity, it was suggested that this genus needs a taxonomic revaluation. For this, we sequenced a nuclear intron (myoglobin intron 2) and two mitochondrial protein‐coding genes (ND2 and ND3). The 2016 bp of sequence data obtained were aligned and subjected to parsimony, maximum likelihood and Bayesian inference. All three genes strongly reject the monophyly of Apalis but support the placing of all apalises within a broader clade of forest cisticolids which also includes Urolais. Within this forest clade, a subclade is defined which includes the genera Urolais, Schistolais and a well‐supported clade comprising three afromontane species, the Black‐collared Apalis Apalis pulchra, the Ruwenzori Apalis Apalis ruwenzorii and the African Tailorbird Artisornis. This subclade is sister to other members of Apalis, including the type species of the genus the Bar‐throated Apalis Apalis thoracica. A new generic name, Oreolais, is suggested for the Black‐collared and Ruwenzori Apalises.
The Impact of Medical Errors on Ninety‐Day Costs and Outcomes: An Examination of Surgical Patients
Authors: Encinosa William E. , Hellinger Fred J.
Published: July 2008

Objective. To estimate the effect of medical errors on medical expenditures, death, readmissions, and outpatient care within 90 days after surgery.

Data Sources. 2001–2002 MarketScan insurance claims for 5.6 million enrollees.

Study Design. The Agency for Healthcare Research and Quality Patient Safety Indicators (PSIs) were used to identify 14 PSIs among 161,004 surgeries. We used propensity score matching and multivariate regression analyses to predict expenditures and outcomes attributable to the 14 PSIs.

Principal Findings. Excess 90‐day expenditures likely attributable to PSIs ranged from $646 for technical problems (accidental laceration, pneumothorax, etc.) to $28,218 for acute respiratory failure, with up to 20 percent of these costs incurred postdischarge. With a third of all 90‐day deaths occurring postdischarge, the excess death rate associated with PSIs ranged from 0 to 7 percent. The excess 90‐day readmission rate associated with PSIs ranged from 0 to 8 percent. Overall, 11 percent of all deaths, 2 percent of readmissions, and 2 percent of expenditures were likely due to these 14 PSIs.

Conclusions. The effects of medical errors continue long after the patient leaves the hospital. Medical error studies that focus only on the inpatient stay can underestimate the impact of patient safety events by up to 20–30 percent.
Colour change as a result of textile transformations
Authors: Moussa Ali , Dupont Daniel , Steen Daniel , Zeng Xianyi
Published: July 2008

This paper studies the influence of textile structure on its colour. It provides a systematic analysis of the changes in spectral reflectance and hence colour differences between three textile substrates: roving, yarn and woven fabric. The transformations of the reflectance spectrum as a result of the changes of the structure were modelled and the evolutions of the colorimetric coordinates L*, a*, b*, C* and h associated with these various transformations were thus calculated and analysed. The work also offers a useful method of modelling the predicted colour from one substrate form to another, which is important to the textile industry.
Forb Species Establishment Increases with Decreased Grass Seeding Density and with Increased Forb Seeding Density in a Northeast Kansas, U.S.A., Experimental Prairie Restoration
Authors: Dickson Timothy L. , Busby William H.
Published: July 2008

Most prairie restorations fail to produce the diversity of species found in unplowed remnants. This lack of restored diversity is hypothesized to be partly due to the inhibition of forb species by high seeding densities of dominant grasses and partly due to the low seeding densities of forbs used in many restorations. We tested this hypothesis by sowing various densities of forb and warm‐season grass seeds into a restoration begun on bare soil. This is the first replicated restoration experiment we are aware of that varies grass seeding densities to examine the effects on forbs. Four years after seeding, we found that higher densities of grass seeds decreased forb cover, biomass, and richness, and higher densities of forb seeds increased forb richness. These results suggest that dominant grasses compete strongly with native forb species and that many forb species thrive when they are spatially separated from dominant grasses. The results also suggest that seed availability limits the establishment of some forbs. Forb diversity can therefore be increased by decreasing grass seeding density, by increasing forb seeding density, or both. However, forb seeds are generally expensive, and increasing forb seeding density across the entire area of a restoration may be prohibitively expensive. We therefore recommend a low seeding density of dominant grasses, and we recommend spatially separating forbs from dominant grasses by adding most forb seeds to areas with little to no dominant grasses and by adding the rest of the forb seeds to areas with a low density of dominant grasses.
Wetland Restoration and Invasive Species: Apple snail (Pomacea insularum) Feeding on Native and Invasive Aquatic Plants
Authors: Burlakova Lyubov E. , Karatayev Alexander Y. , Padilla Dianna K. , Cartwright Leah D. , Hollas David N.
Published: July 2008

The apple snail Pomacea insularum is an aquatic invasive gastropod native to South America that has the potential to cause harm to aquatic ecosystems, wetland restoration, and agriculture. To predict the potential impact of this snail on aquatic ecosystems, we tested the feeding rate of P. insularum, under laboratory nonchoice experiments, for 3 species of invasive macrophytes and 13 species of native aquatic plants that are important for wetland restoration and health. High levels of consumption were recorded for four native species (Ceratophyllum demersum, Hymenocallis liriosme, Ruppia maritima, and Sagittaria lancifolia) and three invasive species (Colocasia esculenta, Alternanthera philoxeroides, and Eichhornia crassipes). In contrast, less than 10% of the biomass of Spartina alterniflora, Scirpus californicus, Thalia dealbata, and Typha latifolia was consumed by P. insularum over the test period. The palatability of macrophytes was negatively correlated with dry matter content, making our results generalizable to all regions where this invader may be present. Based on our results, wetland restoration in areas invaded by P. insularum should focus on emergent structural species with low palatability. Apple snails should not be considered as agents of biocontrol for invasive plants; although apple snails fed on invasive plants at a high rate, their consumption of many native species was even greater.
Cultural Intelligence and Offshore Outsourcing Success: A Framework of Firm‐Level Intercultural Capability*
Authors: Ang Soon , Inkpen Andrew C.
Published: July 2008

This article discusses the importance of firm‐level cultural intelligence in the context of international business ventures such as offshoring. We identify the recent movement toward global delivery models in offshoring ventures as the strategic imperative for offshoring partners to acquire and develop firm‐level cultural intelligence. Drawing on Earley and Ang's (2003) conceptualization of cultural intelligence and the resource based view of the firm, we develop a conceptual framework of firm‐level cultural intelligence. The framework comprises three dimensions of intercultural capabilities of the firm: managerial, competitive, and structural. We propose items to measure these three dimensions and discuss theoretical and managerial implications.
Offshoring and Cross‐Border Interorganizational Relationships: A Justice Model*
Authors: Beugré Constant D. , Acar William
Published: July 2008

In this article, we develop an interorganizational justice model to explain cross‐border interorganizational relationships. The model contends that cultural distance (construed as the cultural differences between offshoring partners) would influence behavioral uncertainty and the boundary spanners' perceptions of justice. Specifically, the model predicts that high levels of behavioral uncertainty are likely to reduce relational commitment, whereas low levels of behavioral uncertainty are likely to enhance relational commitment. However, boundary spanners' perceptions of distributive, procedural, and interactional justice would mitigate the negative impact of behavioral uncertainty on relational commitment. The model also predicts that culturally similar boundary spanners would be more likely to share similar perceptions of distributive, procedural, and interactional justice than culturally dissimilar boundary spanners. This model has implications for further theoretical discussion and empirical research as well as management practice. Managers could use the interorganizational justice model to assess shared perceptions of justice among boundary spanners and develop transcultural justice competencies.
Time‐Domain and Morphological Analysis of the P Wave. Part II: Effects of Atrial Pacing on P‐Wave Features
Authors: CENSI FREDERICA , RICCI CHIARA , CALCAGNINI GIOVANNI , TRIVENTI MICHELE , RICCI RENATO P. , SANTINI MASSIMO , GRAMMATICO ANDREA , BARTOLINI PIETRO
Published: July 2008

Background: The aim of this study was to compare time‐domain and morphological descriptors of paced and spontaneous P wave in patients prone to atrial fibrillation (AF).

Methods: Nineteen patients (nine women, aged 72 ± 10 years) affected by paroxysmal AF and implanted with dual‐chamber pacemakers (PM) were studied. Two 5‐minute recordings were performed during spontaneous and paced rhythm. Electrocardiogram (ECG) signals were acquired using a 32‐lead mapping system. Patients were grouped into two classes: no previous AF and previous AF groups, according to the number of AF episodes in the 6 months before the analysis.

Results and Conclusion:

During atrial pacing P wave appeared prolonged and morphologically more complex with respect to sinus rhythm. We also found that in patients at lower risk for AF, the atrial pacing changes the atrial activation to a greater extent than in patients at higher risk for AF. Finally, all time‐domain and morphological descriptors of the P wave except one succeed in discriminating “no previous AF” and “previous AF” patients in spontaneous rhythm, while no significant differences have been observed during pacing for any parameters.
Acute Sleep Deprivation is Associated with Increased QT Dispersion in Healthy Young Adults
Authors: OZER ORHAN , OZBALA BURCU , SARI IBRAHIM , DAVUTOGLU VEDAT , MADEN EMIN , BALTACI YASEMIN , YAVUZ SEMA , AKSOY MEHMET
Published: July 2008

Background: Sleep deprivation (SD) is known to be associated with worse cardiovascular outcome including mortality. We investigated the association between acute SD and electrocardiographic maximum QT interval (QTmax), QT, and corrected QT dispersion (QTd/cQTd), which are known to be among predictors of ventricular arrhythmias and sudden death.

Methods: We obtained electrocardiograms of 37 healthy young volunteers (age: 28.45 ± 7.97 years; 11 women) after a night with regular sleep and repeated after a night with sleep debt. We measured minimum QT interval (QTmin), QTmax, QTd, and cQTd in milliseconds.

Results: Average sleep time of the subjects were 7.7 ± 0.8 hours during regular sleep and 1.7 ± 1.6 hours during a night with sleep debt (P < 0.001). Subjects had similar values of QTmin in milliseconds after a night of sleep debt when compared to after regular sleep (347.56 ± 29.75 vs 344.59 ± 20.89; P = 0.51), whereas they had significantly higher values of QTmax, QTd, and cQTd (396.48 ± 30.11 vs 378.10 ± 23.90; P = 0.001, 49.45 ± 9.11 vs 33.51 ± 10.05; P < 0.001 and 54.92 ± 10.42 vs 37.23 ± 10.81; P < 0.001, respectively). In Pearson's correlation analysis, QTmax, QTd, and cQTd were inversely correlated with sleep time (P = 0.012, r =–0.291; P < 0.001, r =–0.625 and P < 0.001, r =–0.616, respectively)

Conclusions: In conclusion, we clearly demonstrated that even one night of SD is associated with significant increase in QTmax, QTd, and cQTd in healthy young adults despite remaining within normal limits. These electrocardiographic changes in acute SD might contribute to development and/or recurrence of arrhythmias. This implication deserves further studies for clarifying the possible linkage between SD and arrhythmias.
Superior Type of Atypical AV Nodal Reentrant Tachycardia: Incidence, Characteristics, and Effect of Slow Pathway Ablation
Authors: OTOMO KIYOSHI , NAGATA YASUTOSHI , TANIGUCHI HIROSHI , UNO KIKUYA , FUJIWARA HIDEOMI , IESAKA YOSHITO
Published: July 2008

Background:

Atypical atrioventricular (AV) nodal reentrant tachycardias (AVNRT) usually exhibit the earliest retrograde atrial activation (ERAA) at the right inferoseptum (Rt‐IS) or proximal coronary sinus (PCS). The purpose of this study was to characterize atypical AVNRT with the ERAA at the right superoseptum (Rt‐SS).

Methods:

Seventy‐three atypical AVNRTs induced in 63 cases were classified into the superior type with the ERAA at the Rt‐SS and inferior type with the ERAA at the Rt‐IS or PCS.

Results:

There were nine superior (12%) and 64 inferior types of atypical AVNRT (88%) in seven and 56 cases, respectively. The superior type exhibited a short atrial‐His interval during the tachycardia (166 ± 41 ms), long His‐atrial interval during the tachycardia (H‐At:156 ± 38 ms), and ventricular pacing at the tachycardia cycle length (TCL) (H‐Ap:201 ± 36 ms), and evidence for a lower common pathway, including second‐degree AV block (four tachycardias) and an H‐Ap being longer than the H‐At (nine tachycardias). The TCL was shorter in the superior type than in the inferior type (322 ± 35 vs 404 ± 110 ms; P < 0.02). In the inferior type, all tachycardias were eliminated after the ablation at the Rt‐IS (44 tachycardias) or PCS (20 tachycardias) where an ERAA was recorded. In the superior type, ablation at the Rt‐IS was ineffective; however, ablation at the right midseptum eliminated seven (78%) of the nine tachycardias.

Conclusions:

The tachycardia circuit of the superior type might have deviated to a more superior part of Koch's triangle than that of the inferior type.
Right Pectoral Implantable Cardioverter Defibrillators: Role of the Proximal (SVC) Coil
Authors: VARMA NIRAJ , EFIMOV IGOR
Published: July 2008

Introduction:

Increased defibrillation thresholds (DFTs) with right active pectoral implantable cardioverter defibrillators (ICDs) and/or right proximal coils (SVC) are attributed to poorer vector. However, SVC affects impedance, current flow, and shock waveform phase duration (PD), which exert independent DFT effects.

Objective:

Compare DFTs and shock characteristics in SVC On with SVC Off in right ICDs.

Methods and Results

: DFT+ testing (n = 42, 62% males, 62 ±15 years, left ventricular ejection fraction (LVEF) 26 ± 11%, ischemic cardiomyopathy 65%, amiodarone 26%) revealed >20% incidence of high DFT (>20J) . Dilated cardiomyopathy and amiodarone increased DFT. Individual impedance variability (25–74 Ω) generated a wide PD range (2.6–8.7 ms). Overall, SVC On reduced impedance by 33% (from 54 ± 10 to 35 ± 5Ω, P< 0.0001), and shortened PD (from 5.45 ± 1.20 to 3.67 ± 0.74 ms, P< 0.01). SVC On affected DFTs in 19/42 (45%) patients. SVC On was beneficial in 12/19. PD shortened but current flow remained unaltered. (In these, SVC Off impedance was >45Ω and PD >5 ms.) SVC On was detrimental in 7/19 despite increasing current flow. In these, PD shortened excessively (median 2.9 ms) because impedance was low (31 ± 4Ω). In 3/6 cases with DFTs >20 J in both SVC On and Off, PD optimization reduced DFT. Overall, selection of best SVC configuration or deliberate PD programming yielded DFTs ≤20 J in >90% patients, reducing need for system modification to <7%.

Conclusions

: Right pectoral active ICDs have high DFTs. The SVC coil may be detrimental when pulse waveform excessively shortens. Noninvasive maneuvers, for example, SVC and waveform optimization, may improve DFT.
Arrhythmia Mechanisms in the Failing Heart
Authors: JIN HONGWEI , LYON ALEXANDER R. , AKAR FADI G.
Published: July 2008

Background:

Heart failure (HF) claims over 200,000 lives annually in the United States alone. Approximately 50% of these deaths are sudden and unexpected, and presumably the consequence of lethal ventricular tachyarrhythmias. Electrical remodeling that occurs at the cellular and tissue network levels predisposes patients with HF to malignant arrhythmias. Our limited understanding of fundamental arrhythmia mechanisms has hampered the development of effective treatment strategies for these patients.

Methods and Conclusions:

In this review, we outline recent advances in our understanding of arrhythmia mechanisms in the failing heart, highlighting various aspects of remodeling of ion channels, calcium handling proteins, and gap junction‐related molecules. As will be discussed, these changes promote the prolongation of the action potential, the enhancement of spatio‐temporal gradients of repolarization, the formation of calcium‐mediated triggers and conduction abnormalities, all of which combine to form an electrophysiological substrate that is ripe for the genesis of lethal arrhythmias and sudden cardiac death.
Atrial Fibrillation and Mitral Valve Repair
Authors: JOVIN ANGELIKA , OPREA DANA A. , JOVIN ION S. , HASHIM SABET W. , CLANCY JUDE F.
Published: July 2008

Atrial fibrillation (AF) is present in 30–40% of patients presenting for mitral valve surgery. In patients undergoing mitral valve repair, the presence of AF may be associated with increased mortality and morbidity and this is also the case in patients in whom AF persists postoperatively. Advances in understanding the pathogenesis of AF led to techniques that include both mitral valve repair and ablation of AF. The concomitant surgical treatment of AF during mitral surgery has become a commonly performed procedure, which was shown to be safe and which may improve the outcome for patients. AF after mitral valve replacement is an accepted indication for anticoagulation, but the data supporting anticoagulation in patients after mitral valve
repair who convert to sinus rhythm are sparse. This article reviews the available data regarding outcomes of mitral repair and how they are influenced by AF and its therapy.
A Single Mahaim Fiber Causing Both Antidromic and Orthodromic Reciprocating Tachycardia
Authors: KALBFLEISCH STEVEN , BOWMAN KATHY , AUGOSTINI RALPH
Published: July 2008

We describe the case of a 56‐year‐old woman referred for electrophysiological (EP) testing for medically refractory supraventricular arrhythmias. During the EP study, the patient was found to have a right free wall atriofasicular (Mahaim type) accessory pathway and an inducible left bundle morphology preexcited tachycardia secondary to antidromic reciprocating tachycardia. The patient also had an inducible narrow complex orthodromic reciprocating tachycardia (ORT). Mapping revealed that the earliest site of retrograde atrial activation during ORT was along the lateral tricuspid annulus. This was the same location where the atriofasicular accessory pathway potential was recorded during sinus rhythm. Radiofrequency ablation at this site eliminated inducibility of both tachycardias and any evidence of antegrade or retrograde accessory pathway conduction. This report describes the case of a very rare right free wall Mahaim type fiber with both antegrade and retrograde conduction capabilities responsible for both antidromic and ORT.
Usefulness of Interatrial Conduction Time to Distinguish Between Focal Atrial Tachyarrhythmias Originating from the Superior Vena Cava and the Right Superior Pulmonary Vein
Authors: CHANG KUAN‐CHENG , CHEN JAN‐YOW , LIN YU‐CHIN , HUANG SHOEI K. STEPHEN
Published: July 2008

Objective: Differentiation of the tachycardia originating from the superior vena cava (SVC) or the right superior pulmonary vein (RSPV) is limited by the similar surface P‐wave morphology and intraatrial activation pattern during tachycardia. We sought to find a simple method to distinguish between the two tachycardias by analyzing the interatrial conduction time.

Methods: Sixteen consecutive patients consisting of 8 with SVC tachycardia and the other 8 with RSPV tachycardia were studied. The interatrial conduction time from the high right atrium (HRA) to the distal coronary sinus (DCS) and the intraatrial conduction time from the HRA to the atrial electrogram at the His bundle region (HIS) were measured during the sinus beat (SR) and during the tachycardia‐triggering ectopic atrial premature beat (APB). The differences of interatrial (Δ[HRA‐DCS]SR‐APB) and intraatrial (Δ[HRA‐HIS]SR‐APB) conduction time between SR and APB were then obtained.

Results: The mean Δ[HRA‐DCS]SR‐APB was 1.0 ± 5.2 ms (95% confident interval [CI]–3.3–5.3 ms) in SVC tachycardia and 38.5 ± 8.8 ms (95% CI 31.1–45.9 ms) in RSPV tachycardia. The mean Δ[HRA‐HIS]SR‐APB was 1.5 ± 5.3 ms (95% CI –2.9–5.9 ms) in SVC tachycardia and 19.9 ± 12.0 ms (95% CI 9.9–29.9 ms) in RSPV tachycardia. The difference of Δ[HRA‐DCS]SR‐APB between SVC and RSPV tachycardias was wider than that of Δ[HRA‐HIS]SR‐APB (37.5 ± 9.3 ms vs. 18.4 ± 15.4 ms, P < 0.01).

Conclusions: The wide difference of the interatrial conduction time Δ[HRA‐DCS]SR‐APB between SVC and RSPV tachycardias is a useful parameter to distinguish the two tachycardias and may avoid unnecessary atrial transseptal puncture.
Intracardiac Echo‐Guided Radiofrequency Catheter Ablation of Atrial Fibrillation in Patients with Atrial Septal Defect or Patent Foramen Ovale Repair: A Feasibility, Safety, and Efficacy Study
Authors: LAKKIREDDY DHANUNJAYA , RANGISETTY UMAMAHESH , PRASAD SUBRAMANYA , VERMA ATUL , BIRIA MAZDA , BERENBOM LOREN , PIMENTEL RHEA , EMERT MARTIN , ROSAMOND THOMAS , FAHMY TAMER , PATEL DIMPI , BIASE LUIGI DI , SCHWEIKERT ROBERT , BURKHARDT DAVID , NATALE ANDREA
Published: July 2008

Introduction: Patients with atrial septal defect (ASD) are at higher risk for atrial fibrillation (AF) even after repair. Transseptal access in these patients is perceived to be difficult. We describe the feasibility, safety, and efficacy of pulmonary vein antral isolation (PVAI) in these patients.

Method: We prospectively compared post‐ASD/patent foramen ovale (PFO) repair patients (group I, n = 45) with age‐gender‐AF type matched controls (group II, n = 45). All the patients underwent PVAI through a double transseptal puncture with a roving circular mapping catheter technique guided by intracardiac echocardiography (ICE). The short‐term (3 months) and long‐term (12 month) failure rates were assessed.

Results: In group I, 23 (51%) had percutaneous closure devices and 22 (49%) had a surgical closure. There was no significant difference between group I and II in the baseline characteristics. Intracardiac echo‐guided double transseptal access was obtained in 98% of patients in group I and in 100% of patients in group II. PVAI was performed in all patients, with right atrial flutter ablation in 7 patients in group I and in 4 patients in group II. Over a mean follow‐up of 15 ± 4 months, group I had higher short‐term (18% vs 13%, P = 0.77) and long‐term recurrence (24% vs 18%, P = 0.6) than group II. There was no significant difference in the perioperative complications between the two groups. Echocardiography at 3 months showed interatrial communication in 2 patients in group I and 1 patient in group II, which resolved at 12 months.

Conclusion: Percutaneous AF ablation using double transseptal access is feasible, safe, and efficacious in patients with ASD and PFO repairs.
Benefit of Primary Prevention Implantable Cardioverter‐Defibrillators in the Setting of Chronic Kidney Disease: A Decision Model Analysis
Authors: AMIN MITESH S. , FOX AARON D. , KALAHASTY GAUTHAM , SHEPARD RICHARD K. , WOOD MARK A. , ELLENBOGEN KENNETH A.
Published: July 2008

Introduction: Primary prevention ICD trials have excluded patients with CKD. Comorbidities and lower life expectancy in patients with CKD make the benefit of primary prevention ICD implantation uncertain.

Methods: A decision analysis model was devised to evaluate the risks and benefits of implantable cardioverter‐defibrillators (ICD) implantation in patients with chronic kidney disease (CKD) who meet current criteria for a primary prevention ICD. Published data capturing event rates, infection risks, and overall survival in CKD patients with and without ICDs were utilized. Variables included patient's age, GFR and stage of CKD, probability of sudden cardiac death (SCD), and device implantation mortality.

Results: The benefit of an ICD for primary prevention of SCD in patients with CKD depends primarily on the patient's age and stage of kidney disease. With stages 1 and 2 CKD, ICD implantation reduces mortality. However, in patients with more advanced stages of CKD, the benefit is less significant and age‐dependent. This is attributed to patients with advanced CKD having a higher procedural risk and decreased life expectancy. With average procedural mortality, ICD implantation is favored at ages <80 for stage 3, ages <75 for stage 4, and ages <65 for stage 5. As procedural mortality rates increase, age thresholds for ICD implantation decrease.

Conclusions: Our model shows that benefit from primary prevention ICD implantation is determined by the patient's age and stage of kidney disease. While there is limited impact with lower stages of CKD, careful consideration of ICD implantation is suggested for older patients with more advanced stages of kidney disease.
Impact of a Patent Foramen Ovale on Paroxysmal Atrial Fibrillation Ablation
Authors: KNECHT SÉBASTIEN , WRIGHT MATTHEW , LELLOUCHE NICOLAS , NAULT ISABELLE , MATSUO SEIICHIRO , O'NEILL MARK D. , LOMAS OLIVER , DEPLAGNE ANTOINE , BORDACHAR PIERRE , SACHER FREDERIC , DERVAL NICOLAS , HOCINI MÉLÈZE , JAÏS PIERRE , CLÉMENTY JACQUES , HAÏSSAGUERRE MICHEL
Published: July 2008

Introduction: A patent foramen ovale (PFO) is located at the anterior and superior part of the anatomical interatrial septum, the area that is targeted during transseptal puncture. This study sought to investigate the impact of accessing the left atrium via a PFO on paroxysmal AF ablation.

Methods: From March 2004, 203 patients (55 ± 11 years) underwent catheter ablation for paroxysmal AF (80 ± 71 months), with the endpoint being electrical isolation of all pulmonary veins (PV) and AF noninducibility. The presence of a PFO was determined by both transesophageal echocardiography and catheter probing. Procedural difficulty was evaluated by radiofrequency (RF), procedural, and fluoroscopic durations. Clinical follow‐up was also investigated.

Results: A PFO was detected in 27 patients (13%) by transesophageal echocardiography and in 22 additional patients (total 49 patients, 24%), by catheter probing (P < 0.001). A PFO was associated with longer total RF applications (57 ± 19 vs 51 ± 18 min, P = 0.04) and RF applications to isolate the PVs (42 ± 16 vs 35 ± 12 min, P = 0.001). Procedural and fluoroscopic times were unaffected. Seventy‐three patients (36%) required a second procedure; there was no difference in the number of PV reconnections (1.3 vs 1.8 veins, P = NS). After a mean follow‐up of 19 ± 9 months, 194/203 patients (96%) were free of AF, with no difference in patients in whom a PFO had been used.

Conclusion: Although isolation of PVs is longer, overall procedural duration and success is not affected when using a PFO compared with a transseptal puncture. The presence of a PFO is underestimated by transesophageal echocardiography with brachial injection when compared with catheter probing.
Hydatid Cyst of the Right Ventricle in Early Pregnancy
Authors: Soleimani Abbas , Sahebjam Mohammad , Marzban Mehrab , Shirani Shapour , Abbasi Ali
Published: July 2008

Although hydatic cyst disease rarely involves myocardium and endocardium, cardiac echinococcosis, a potentially life‐threatening condition, should be managed promptly. We report a case of right ventricle hydatid cyst detected after syncopal attack in a pregnant woman by using echocardiography.
Effect of Alcohol‐Induced Septal Ablation on Left Atrial Volume and Ejection Fraction Assessed by Real Time Three‐Dimensional Transthoracic Echocardiography in Patients with Hypertrophic Cardiomyopathy
Authors: Hage Fadi G. , Karakus Gultekin , Luke, Jr. William D. , Suwanjutah Thouantosaporn , Nanda Navin C. , Aqel Raed A.
Published: July 2008

Alcohol‐induced septal ablation (AISA) is an accepted treatment for hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) outflow obstruction who are unresponsive to medical therapy. As left atrial (LA) enlargement has been correlated with increased morbidity and mortality in HCM, we assessed LA volumes and ejection fraction (EF) prior to and after AISA using real time three‐dimensional (3D) transthoracic echocardiography (TTE) in 12 patients (9 women; mean age 52 ± 15 years; 11 Caucasian). All patients underwent successful AISA with no complications and their resting left ventricular outflow gradients decreased from 40.5 ± 22.2 to 9.1 ± 17.6 mmHg (P < 0.001) while their gradients with provocation decreased from 126.2 ± 31.7 to 21.8 ± 28.0 mmHg (P < 0.001). All patients showed improvements in their New York Heart Association (NYHA) functional class. Both the LA end‐systolic (45.2 ± 12.9 to 37.2 ± 13.7 ml, P < 0.0001) and end‐diastolic (79.6 ± 18.9 to 77.1 ± 18.6 ml, P = 0.001) volumes decreased after AISA. The LA EF increased from 43.1 ± 9.0 to 52.5 ± 8.8% (P = 0.001). The increase in LA EF correlated with the decrease in the resting left ventricular outflow gradient (R =−0.647, P = 0.03). In conclusion, 3D echocardiography can be utilized to follow LA function after AISA for HCM. AISA results in clinical improvement in patients with HCM and in improvement of LA EF that is correlated with the decrease in the left ventricular outflow gradient.
Reading George Spindler
Authors: McDermott Ray
Published: July 2008

George Spindler is often acknowledged as a founder of the anthropology of education, but ties between Spindler, the new field, and their roots in the culture and personality school of U.S. anthropology are rarely explored. This article and the one that follows (“Using Visual Stimuli in Ethnography,” Spindler 2008) highlight theoretical concerns shaping the goals and methods of Spindler's work. McDermott offers background and then Spindler summarizes his 60 years of fieldwork and findings on the relations among culture, personality, and education. [origins of the field, culture and personality, field techniques]
Socialist Consciousness Raising and Cuba's School to the Countryside Program
Authors: Blum Denise
Published: July 2008

As a participant‐observer, the author relates observations, interviews, and surveys from her experience in a Cuban Escuela al Campo (“School to the Countryside,” or EAC) camp located on a collective farm outside of the city of Havana. The Pioneers, the youth section of the official Cuban Communist Party, organize the EAC program nationwide. The program's rugged, military lifestyle experience is required for city‐based junior high school students in Cuba, an essential rite of passage of the politicization and socialist consciousness‐raising efforts designed by the Revolutionary Government. The author proposes that beneath the revolutionary symbols and activities of the EAC, a new and latent socialist consciousness has been evolving for some time, one that reflects neither an absolute nor an erosion of socialist ideals. Rather, this consciousness (conciencia), much like A. Yurchak (2005) demonstrates in his study of Gorbachev's Russia, reveals a system that inhabits incommensurable positions; Cuba's socialism is both everlasting and steadily declining, at the same time full of vigor and bleakness, as well as dedicated to high ideals and devoid of them. None of these positions is a mask. The intention of this article is, therefore, to show how each is real and mutually constitutive in the EAC. Understanding this peculiar dynamic is crucial for understanding the everyday practices of students, their parents and teachers, the socializing function of Cuban schools, and the seemingly duplicitous behavior in Cuban's daily lives. [Cuban education, socialism, value formation]
Effect of A Site Substitution on the Properties of CaBi2Nb2O9 Ferroelectric Ceramics
Authors: Zhang Xiaodong , Yan Haixue , Reece Michael J
Published: July 2008

The effect of A‐site substitution on the piezoelectric coefficient, high‐temperature dc resistivity, and thermal depoling behavior of Aurivillius phase CaBi2Nb2O9 ferroelectric ceramics was investigated. Ceramics with the general formula of Ca1−xMxBi2Nb2O9, where M=Na, (Na,Ce), (Na,La), and La, were prepared by conventional solid‐state sintering. All the ceramics were single‐phase ferroelectrics with high Curie points (∼900°C). The doped ceramics, Ca0.9Na0.1Bi2Nb2O9, Ca0.9(NaLa)0.1Bi2Nb2O9, Ca0.95La0.05Bi2Nb2O9, and Ca0.9La0.1Bi2Nb2O9, had improved resistance to thermal depoling compared with Ca2Bi2Nb2O9 and were stable up to 800°C. The donor dopants increased the dc electrical resistivity, while the acceptor dopants decreased it. The donor‐doped Ca0.95La0.05Bi2Nb2O9 had a higher piezoelectric constant (d33=12.8 pC/N) compared with CaBi2Nb2O9 (d33=5.8 pC/N), and its electrical resistivity was higher than 106Ω·cm at 600°C. These properties suggest that doped CaBi2Nb2O9 ceramics might be good candidates for high‐temperature piezoelectric applications.