bluuebunny/crossref_metadata_2025 huggingface dataset:
Atrial Noninvasive Activation Mapping of Paced Rhythm Data
Authors: Modre Robert , Tilg Bernhard , Fischer Gerald , Hanser Friedrich , Messnarz Bernd , Seger Michael , Schocke Michael F.H. , Berger Thomas , Hintringer Florian , Roithinger Franz X.
Published: August 2010

Introduction: Atrial arrhythmias have emerged as a topic of great interest for clinical electrophysiologists. Noninvasive imaging of electrical function in humans may be useful for computer‐aided diagnosis and treatment of cardiac arrhythmias, which can be accomplished by the fusion of data from ECG mapping and magnetic resonance imaging (MRI).

Methods and Results: In this study, a bidomain‐theory–based surface heart model activation time (AT) imaging approach was applied to paced rhythm data from four patients. Pacing sites were the right superior pulmonary vein, left inferior pulmonary vein, left superior pulmonary vein, coronary sinus, posterior wall of right atrium, and high right atrium. For coronary sinus pacing, the AT pattern of the right atrium was compared with a CARTO map. The root mean square error between CARTO geometry (85 nodal points) and the surface model of the right atrium was 8.6 mm. The correlation coefficient of the noninvasively obtained AT map of the right atrium and the CARTO map was 0.76. All pulmonary vein pacing sites were identified. The reconstructed pacing site of right posterior atrial pacing correlates with the invasively determined pacing catheter position with a localization distance of 4 mm.

Conclusion: The individual anatomic model of the atria of each patient enables accurate noninvasive AT imaging within the atria, resulting in a localization error for the pacing sites within 10 mm. Our findings may have implications for imaging of atrial activity in patients with focal arrhythmias or focal triggers. (J Cardiovasc Electrophysiol, Vol. 14, pp. 712‐719, July 2003)
Ambulatory Electrocardiogram‐Based Tracking of T Wave Alternans in Postmyocardial Infarction Patients to Assess Risk of Cardiac Arrest or Arrhythmic Death
Authors: Verrier Richard L. , Nearing Bruce D. , Rovere Maria Teresa La , Pinna Gian Domenico , Mittleman Murray A. , Bigger J. Thomas , Schwartz Peter J. ,   ATRAMI Investigators
Published: August 2010

Introduction: This is the first study to assess T wave alternans (TWA) analyzed from routine ambulatory electrocardiograms (AECGs) to identify postmyocardial infarction (post‐MI) patients at increased risk for arrhythmic events.

Methods and Results: The new method of modified moving average (MMA) analysis was used to measure TWA magnitude in 24‐hour AECGs from ATRAMI, a prospective study of 1,284 post‐MI patients. Using a nested case‐control approach, we defined cases as patients who experienced cardiac arrest due to documented ventricular fibrillation or arrhythmic death during the follow‐up period of 21 ± 8 months. We analyzed 15 cases and 29 controls matched for sex, age, site of MI, left ventricular ejection fraction, thrombolysis, and beta‐blockade therapy. TWA was reported as the maximum 15‐second value at three predetermined times associated with cardiovascular stress: maximum heart rate, 8:00 A.M., and maximum ST segment deviation. TWA increased significantly from baseline in both leads at each time point (P ≪ 0.01) in cases and controls. TWA in V5 increased more in cases than controls during peak heart rate (P = 0.005) and at 8:00 A.M. (P = 0.02). A 4‐ to 7‐fold higher odds of life‐threatening arrhythmias was predicted by TWA level above the 75th percentile during maximum heart rate in leads V1 (odds ratio [OR] 4.2, 95% confidence interval [CI]: 1.1–16.3, P = 0.04) and V5 (OR 7.9, 95% CI: 1.9–33.1, P = 0.005). TWA at 8:00 A.M. also predicted risk in leads V1 (OR = 5.0, 95% CI: 1.2–20.5, P = 0.02) and V5 (OR = 4.2, 95% CI: 1.1–16.3, P = 0.04).

Conclusion: TWA measurement from routine 24‐hour AECGs is a promising approach for risk stratification for cardiac arrest and arrhythmic death in relatively low‐risk post‐MI patients. (J Cardiovasc Electrophysiol, Vol. 14, pp. 705‐711, July 2003)
Comparison of Coronary Sinus Morphology in Patients With and Without Atrioventricular Nodal Reentrant Tachycardia by Intracardiac Echocardiography
Authors: OKUMURA YASUO , WATANABE ICHIRO , YAMADA TAKESHI , OHKUBO KIMIE , MASAKI RIKO , SUGIMURA HIDEZOU , HASHIMOTO KENICHI , KOFUNE TATSUYA , TAKAGI YASUHIRO , WAKITA RIE , OSHIKAWA NAOHIRO , SAITO SATOSHI , OZAWA YUKIO , KANMATSUSE KATSUO , YOSHIKAWA YASUYUKI , ASAKAWA YUKO
Published: August 2010

Introduction: Dual AV nodal physiology is the electrophysiologic substrate for AV nodal reentrant tachycardia (AVNRT), but the anatomic basis for this arrhythmia remains to be elucidated. Atrial flutter (AFL) has been shown to be more frequently inducible in patients with AVNRT.

Methods and Results: A 3.2‐French, 20‐MHz intracardiac ultrasound (ICUS) catheter was introduced into the coronary sinus (CS), and two‐dimensional ICUS images were recorded during transducer pullback in 21 patients with AVNRT and 18 control patients. Three‐dimensional reconstruction of the CS was created using the TomTec Imaging system. The area of the CS lumen at 15 mm within the CS ostium (os) was not significantly different in patients with and without AVNRT (54.4 ± 34.7 mm2 vs 39.1 ± 28.5 mm2). However, the area of the CS os was significantly larger in patients with AVNRT than in those without (112.1 ± 60.9 mm2 vs 71.7 ± 44.4 mm2, P < 0.05). Three‐dimensional morphology of the CS os revealed flaring in patients with AVNRT, giving it a “windsock” appearance. Sustained AFL was induced in 10 of 21 patients with AVNRT, but in none of 18 control patients (P < 0.005).

Conclusion: The CS os was significantly wider in patients with AVNRT than in those without. These findings may have important implications for arrhythmia pathogenesis in AVNRT as well as AFL. (J Cardiovasc Electrophysiol, Vol. 15, pp. 269‐273, March 2004)
Catheter Ablation of Ventricular Tachycardia by Intramyocardial Injection of Ethanol in an Animal Model of Chronic Myocardial Infarction
Authors: REEK SVEN , GELLER J. CHRISTOPH , SCHILDHAUS HANS‐ULRICH , MAHNKOPF DIRK , MITTAG JOERG , KLEIN HELMUT U.
Published: August 2010

Introduction: Direct injection of ethanol into myocardium has been shown to create large, well‐demarcated lesions with transmural necrosis in normal ventricular myocardium and in regions of healed myocardial infarction. The aim of this study was to investigate the effects of direct ethanol injection on the inducibility of ventricular tachycardia (VT) in an animal model of chronic myocardial infarction.

Methods and Results: Eight sheep with reproducibly inducible VT underwent an electrophysiologic study 139 ± 65 days after myocardial infarction. Noncontact mapping was used to analyze induced VT. Fifteen different VTs were targeted for catheter ablation. Ablation was achieved by catheter‐based intramyocardial injection of a mixture of 96% ethanol, glycerine, and iopromide (ratio 3:1:1). Direct intramyocardial ethanol injection resulted in noninducibility of any VT 20 minutes after ablation in 7 of 8 animals. Four of 5 animals with initially successful ablation remained noninducible for any VT at follow‐up study at least 2 days after the ablation procedure. Microscopic examination revealed homogeneous lesions with interstitial edema, intramural hemorrhage, and myofibrillar degeneration at the lesion border. The lesions were well demarcated from the surrounding tissue by a border zone of neutrophilic infiltration.

Conclusion: Catheter ablation of VT by direct intramyocardial injection of ethanol during the chronic phase of myocardial infarction is feasible. It may be a useful tool for catheter ablation when the area of interest is located deep intramyocardially or subepicardially or when a more regional approach requires ablation of larger amounts of tissue. (J Cardiovasc Electrophysiol, Vol. 15, pp. 332‐341, March 2004)
Role of Dipolar and Nondipolar Components of the T Wave in Determining the T Wave Residuum in an Isolated Rabbit Heart Model
Authors: BIAGETTI MARCELO O. , ARINI PEDRO D. , VALVERDE ESTEBAN R. , BRETRAN GUILLERMO C. , QUINTEIRO RICARDO A.
Published: August 2010

Introduction: Repolarization heterogeneity has been shown to constitute a substrate for malignant ventricular arrhythmias. Noninvasive measurement of abnormal repolarization through assessment of QT interval dispersion from the resting standard 12‐lead ECG initially had shown promise in assessing arrhythmia risk but was challenged recently. The relative T wave residuum (TWR) has been proposed recently to reflect regional repolarization dispersion more accurately. We analyzed the role played by the dipolar and nondipolar components in determining TWR.

Methods and Results: Singular value decomposition was applied to the repolarization signals obtained from isolated rabbit hearts using a 5 × 8 array multielectrode recording system during premature beats (N = 11) and after d‐sotalol (N = 9) exposure. Both the dipolar and nondipolar components of the T wave increased significantly during premature stimulation and after d‐sotalol exposure. The relative TWR decreased significantly during premature stimulation but did not change after d‐sotalol. Changes in the dipolar and nondipolar components of the second half of the T wave were significantly greater than those corresponding to the first half during premature stimulation, and a significant correlation was observed between the nondipolar components of the second half of the T wave and the Tpeak–end interval.

Conclusion: Conditions exist during which both the dipolar and nondipolar components can change simultaneously. Under these conditions, the relative TWR may not reflect regional heterogeneity of repolarization with accuracy. The nondipolar components of the second half of the T wave can be linked to assessment of the transmural dispersion of repolarization. (J Cardiovasc Electrophysiol, Vol. 15, pp. 356‐363, March 2004)
Characterization of a New Pulmonary Vein Variant Using Magnetic Resonance Angiography:
Authors: LICKFETT LARS , KATO RITSUSHI , TANDRI HARIKRISHNA , JAYAM VINOD , VASAMREDDY CHANDRASEKHAR R. , DICKFELD TIMM , LEWALTER THORSTEN , LUDERITZ BERNDT , BERGER RONALD , HALPERIN HENRY , CALKINS HUGH
Published: August 2010

Introduction: Catheter ablation of the pulmonary veins (PVs) for prevention of recurrent atrial fibrillation requires precise anatomic information. We describe the characteristics of a new anatomic variant of PV anatomy using magnetic resonance angiography.

Methods and Results: A 1.5‐T magnetic resonance imaging system with a body coil or a torso phased‐array coil was used before and after gadolinium injection. Magnetic resonance angiograms were acquired with a breath‐hold three‐dimensional fast spoiled gradient‐echo imaging sequence in the coronal plane. Three‐dimensional reconstruction with maximum intensity projections and multiplanar reformations was performed. A newly described variant PV ascending from the roof of the left atrium was found in 3 of 91 subjects. The mean ostial diameter of the roof PV was 7 ± 2 mm, the mean distance from the ostium to the first branching point was 22 ± 8.5 mm, and the mean distance to the right superior PV was 3.3 ± 0.6 mm.

Conclusion: We refer to the newly described variant of PV anatomy as the “right top pulmonary vein.” It is important to be aware of this anatomic pattern to avoid inadvertent catheter intubation, which can result in misleading mapping results and PV stenosis. (J Cardiovasc Electrophysiol, Vol. 15, pp. 538‐543, May 2004)
Resolution of Abnormal Body Surface Maps in Children with Atrial Septal Defect after Intracardiac Repair
Authors: ASANO YUH , IZUMIDA NAOMI , KAWANO SEIKO , SAWANOBORI TOHRU , HIRAOKA MASAYASU
Published: August 2010

Introduction: The genesis of repolarization abnormalities of ECG waveforms in atrial septal defect (ASD), which typically is characterized by right ventricular (RV) volume overload, has not been explored, particularly in association with postoperative hemodynamic improvement. The aim of this study was to evaluate the effects of reduced RV overload after ASD closure on depolarization and repolarization abnormalities on body surface maps (BSMs).

Methods and Results: BSMs of 14 children with ASD were recorded preoperatively and at early postoperative (1–6 months) and late postoperative (>9 months) stages. BSMs of 31 age‐matched healthy children were studied as normal controls. Before intracardiac repair, QRS isopotential maps of children with ASD showed delayed RV breakthrough and subsequent rightward enlargement of the positive area with a maximum shifting to the right. Delayed conduction of the RV, particularly at the outflow tract area, was noted. The preoperative QRST isointegral maps exhibited the two‐maximum pattern reflecting repolarization abnormality. The delayed appearance of breakthrough and delayed RV conduction on the QRS isopotential maps persisted from the preoperative to the late postoperative stage, whereas the two‐maximum pattern on the QRST isointegral maps normalized to the one‐dipole pattern at an early stage after repair.

Conclusion: Abnormal repolarization parameters in ASD patients showed rapid improvement postoperatively, despite the persistence of depolarization abnormalities. Therefore, the two‐maximum pattern on the QRST isointegral maps indicates a primary T wave change due to hemodynamic RV volume overload.
Radiofrequency Ablation of Idiopathic Ventricular Fibrillation Guided by Noncontact Mapping
Authors: BETTS TIMOTHY R. , YUE ARTHUR , ROBERTS PAUL R. , MORGAN JOHN M.
Published: August 2010

A 32‐year‐old man with idiopathic ventricular fibrillation and an implantable cardioverter defibrillator presented during a ventricular fibrillation storm. Frequent monomorphic ventricular ectopics with left bundle branch block morphology were documented, some of which initiated fibrillation. He underwent noncontact mapping of the right ventricle, during which the ventricular ectopics were mapped to a site in the free wall displaying a diastolic potential 80 ms before ectopic QRS onset. Following three radiofrequency energy applications, the ectopics were abolished. After 11‐month follow‐up, he has experienced no further arrhythmias. Noncontact mapping may identify ablatable triggers of ventricular fibrillation and lead to successful outcomes even when only single ectopics are present.
Atrial Natriuretic Peptides During Experimental Atrial Tachycardia:
Authors: SCHOONDERWOERD BAS A. , CRIJNS HARRY J.G.M. , VAN VELDHUISEN DIRK J. , BOOMSMA FRANS , VAN DEN BERG MAARTEN P. , BEL KLAAS J. , VAN GELDER ISABELLE C.
Published: August 2010

Introduction: Atrial tachycardia and chronic heart failure (CHF) are associated with elevated levels of atrial natriuretic peptide (ANP) and its amino terminal part NT‐ANP. Chronic high atrial rates may cause CHF due to a rapid ventricular response. The aim of this study was to establish the contribution of elevated atrial rate and of high ventricular rate, resulting in CHF, on ANP and NT‐ANP levels during chronic atrial tachycardia.

Methods and Results: Thirteen goats (AV‐paced group) were subjected to 4 weeks of rapid AV pacing with an atrial and ventricular rate of 240 beats/min. Another five goats (A‐paced group) were subjected to 4 weeks of atrial pacing at 240 beats/min while the ventricular rate was kept low and regular at 80 beats/min. Pacing was interrupted only for measurement of right atrial (RA) and left ventricular (LV) diameter and sampling for ANP, NT‐ANP, and renin. In the AV‐paced group, RA and LV diameter reached 152% and 109% of baseline values, respectively. Both ANP and NT‐ANP (8.3 ± 9.2 pmol/L and 0.5 ± 0.4 nmol/L at baseline, respectively) increased progressively (53.1 ± 37.9 pmol/L and 2.0 ± 0.9 nmol/L, respectively, after 4 weeks). There was a significant correlation between the magnitude of atrial dilation and natriuretic peptide levels after 3 days. In A‐paced goats, however, RA and LV diameters did not change. Furthermore, ANP and NT‐ANP levels (9.1 ± 6.0 pmol/L and 0.8 ± 0.2 nmol/L at baseline, respectively) were unchanged after 4 weeks (5.3 ± 3.4 pmol/L and 0.6 ± 0.2 nmol/L, respectively).

Conclusion: Elevated levels of ANPs during chronic atrial tachycardia are related to a high ventricular rate rather than a high atrial rate alone. Rather than atrial tachycardia, the atrial hemodynamic burden is an important determinant of the sustained ANP response.
Cryocatheter Ablation of Right Ventricular Outflow Tract Tachycardia
Authors: KURZIDIM KLAUS , SCHNEIDER HANS‐JÜRGEN , KUNISS MALTE , SPERZEL JOHANNES , GREISS HARALD , BERKOWITSCH ALEXANDER , PITSCHNER HEINZ FRIEDRICH
Published: August 2010

Introduction: Cryocatheter techniques have been successfully applied to treat supraventricular tachycardia but there are no reports on their value in treating ventricular tachycardia (VT). We present our initial experience with cryocatheter ablation of right ventricular outflow tract (RVOT) tachycardia.

Methods and Results: Cryocatheter ablation was attempted in 14 patients (13 females, age 45.9 ± 12.7 years) who were highly symptomatic due to frequent monomorphic ventricular extrasystole (VES) or nonsustained VT originating within the RVOT. A 9‐Fr, 8‐mm‐tip cryocatheter was used for both mapping and ablation. Cryoablation was started after localizing the arrhythmic focus by pace and activation mapping. Ablation success, defined by complete disappearance of target VES/VT acutely and during a follow‐up of 9.3 ± 1.4 weeks, was achieved in 13 of 14 patients. Ablation was successful with local activation times of 35 ± 4 ms, 5.8 ± 3.3 applications, 18.8 ± 7.5 minutes total cryo time, 9.4 ± 4.2 minutes fluoroscopy time, and 66.9 ± 26.1 minutes total procedure time, the latter two measures showing a reduction with number of patients treated. Three patients reported slight pain related to local pressure of the catheter on the RVOT wall. No pain was described related to delivery of cryothermal energy.

Conclusions: Initial experience shows that focal VES/VT originating in the RVOT can be successfully treated using cryocatheter ablation. Acute and short term success rates, fluoroscopy times, and duration of procedure are comparable to conventional ablation techniques. A major advantage seems to be the virtual absence of ablation related pain.
Magnetization reversal behavior in high coercivity Zr doped α-Fe/Nd2Fe14B nanocomposite alloys
Authors: Zhang P. Y. , Hiergeist R. , Lüdke J. , Albrecht M. , Ge H. L.
Published: August 2010

The magnetization reversal behavior for rapidly solidified Zr-doped α-Fe/Nd2Fe14B alloys with high coercivity has been investigated by analyzing hysteresis curves and recoil loops of demagnetization curves. A drastic increase in the coercivity Hc from 620 to 855 kA/m at room temperature by an addition of 1 at. % Zr in α-Fe/Nd2Fe14B alloys has been observed. The maximum value of the integrated recoil loop area for Zr-doped samples of 3.05 kJ/m3 is much lower than that of the Zr-free sample. This result can be explained by a larger recoverable portion of the magnetization remaining in the Zr-free sample as long as the applied reversal field is below the coercivity Hc, i.e., it is an effect of an increased exchange-coupling in the Zr-free sample. The coercivity mechanism of the α-Fe/Nd2Fe14B nanocomposite magnets was analyzed in terms of the Kondorsky model and the plot of Hc(T)/Ms(T) versus HNmin(T)/Ms(T) (Kronmüller plot), respectively.
Turbulence modulation and drag reduction by spherical particles
Authors: Zhao L. H. , Andersson H. I. , Gillissen J. J. J.
Published: August 2010

This letter reports on the pronounced turbulence modulations and the accompanying drag reduction observed in a two-way coupled simulation of particle-laden channel flow. The present results support the view that drag reduction can be achieved not only by means of polymeric or fiber additives but also with spherical particles.
Indium induced step transformation during InGaN growth on GaN
Authors: Koleske D. D. , Lee S. R. , Thaler G. , Crawford M. H. , Coltrin M. E. , Cross K. C.
Published: August 2010

The surface-step evolution of InGaN quantum-wells (QWs) was studied on GaN (0001). While the GaN template is dominated by single-monolayer steps the frequency of multiple-layer steps increases significantly when InGaN/GaN single- or multiple-QWs are grown. It is proposed that the InGaN multiple-layer step structure arises to partially accommodate the in-plane film strain which is insufficient to trigger bulk InGaN relaxation. This intrinsic multiple-layer step restructuring, when coupled with the strong piezoelectric fields present in the wurtzite group III-nitrides, could explain the enhanced carrier localization in InGaN QWs.
Numerical simulation of impact ionization in Ge/AlxGa1−xAs avalanche photodiode
Authors: Chia C. K.
Published: August 2010

Impact ionization in Ge/AlxGa1−xAs p-i-n heterostructures has been studied using the Monte Carlo technique. The thin (<300 nm) Ge/AlxGa1−xAs single heterojunction structure was found to exhibit large hole (β) to electron (α) ionization coefficient ratio, owing to a higher β in the Ge layer and a lower α in the AlxGa1−xAs layer, together with the dead space effects. The Ge/AlxGa1−xAs avalanche photodiodes are attractive for applications where a wide wavelength detection range is required for compatibility with multiple sources such as in the emerging active optical cable and optical interconnect applications, as well as in the established optical fiber telecommunication systems.
Magnetic anisotropies of laterally confined structures of epitaxial Fe films on GaAs (001)
Authors: Meng K. K. , Lu J. , Wang S. L. , Meng H. J. , Zhao J. H. , Misuraca J. , Xiong P. , von Molnár S.
Published: August 2010

We have investigated magnetic properties of laterally confined structures of epitaxial Fe films on GaAs (001). Fe films with different thicknesses were grown by molecular-beam epitaxy and patterned into regular arrays of rectangles with varying aspect ratios. In-plane magnetic anisotropy was observed in all of the patterned Fe films both at 15 and 300 K. We have demonstrated that the coercive fields can be tuned by varying the aspect ratios of the structures. The magnitudes of the corresponding anisotropy constants have been determined and the shape anisotropy constant is found to be enhanced as the aspect ratio is increased.
Role of twin boundaries in semiconductor to metal transition characteristics of VO2 films
Authors: Yang Tsung-Han , Jin Chunming , Zhou Honghui , Narayan Roger J. , Narayan J.
Published: August 2010

Epitaxial (002) VO2 films were grown on c-sapphire with Ga:ZnO and ZnO buffer layers. We investigated the influence of twin boundaries on the semiconductor-to-metal transition (SMT) characteristics of VO2, when current flows parallel and perpendicular to the twin boundaries. The structure of the twin boundary was kept the same for these two configurations. The hysteresis in SMT characteristics is considerably reduced when current flows parallel to the boundaries compared to that in the normal direction of the boundaries. We present a model to explain these observations and discuss the role of these boundaries on the SMT characteristics, and the importance of grain boundary engineering in the design of VO2 based devices.
Surface potential due to charge accumulation during vacuum ultraviolet exposure for high-k and low-k dielectrics
Authors: Ren H. , Sinha H. , Sehgal A. , Nichols M. T. , Antonelli G. A. , Nishi Y. , Shohet J. L.
Published: August 2010

The surface potential due to charge accumulation during vacuum ultraviolet irradiation of high-k and low-k thin dielectric films is measured. Measurement of the substrate current, which is the sum of the charge-accumulation and photoinjection currents, allows an in situ monitoring of the charge accumulation during irradiation. The relationship between the substrate current and the calculated in situ surface potential is also found, eliminating the need for a separate surface-potential measurement. With a high photon dose, the surface potential and substrate current reach a steady-state value with no further net charge accumulation.
Spatial Allocation of Future Residential Land Use in the Elbe River Basin
Authors: Hoymann Jana
Published: August 2010

In this paper a scenario study of the residential land-use development in the Elbe River Basin is presented. The study uses an approach that empirically determines suitability maps for the application within a land-use-change model. Recent urbanisation processes are explained in the first step and are used in simulations of future land use in the second step. Binomial logistic regression analysis is applied in an analysis of the location characteristics influencing residential land-use change. Estimation results are adapted and used as weights in the calculation of suitability maps, which consist of the location characteristics of residential land-use change. Including policy maps in suitability calculations allows important spatial restrictions to be accounted for and enables the impact of spatial planning on the allocation of residential developments to be analysed. The suitability maps are further applied to the Land Use Scanner model to simulate spatially explicit residential land-use developments in the Elbe River Basin. Results of this study show that empirically determined suitability maps used in models of land-use change can contribute to the operational use of scenario studies in political discussion support. Considerable differences in applied policy maps in terms of their contribution to the sustainable development of residential and use are discussed.
Just Another Night in the Shooting Gallery?: The Syringe, Space, and Affect
Authors: Vitellone Nicole
Published: August 2010

In his ethnography of the shooting gallery Phillipe Bourgois interprets the comment “I started shooting heroin at 14, now I'm 64” as an indication that his respondent's “oppression is fully internalised and, almost like a neo-liberal ideologue, he takes full responsibility for his poverty, illiteracy and homelessness” (1998 Theory, Culture and Society 15). In this paper I consider whether this interpretation adequately gets to grips with a lifetime of attachment to the syringe. Could there be another interpretation for the experience of the shooting gallery? What happens when heroin addiction is addressed not in terms of the political economy of suffering but the political economy of affect? Drawing on my empirical research on the syringe, I examine the affective dimension of the shooting gallery, paying particular attention to the sensation of the syringe. My focus concerns the policy of needle exchange, practices of syringe collection and disposal, and issues of space, waste, and affect. Bringing together poststructural analyses of space, I argue that the excess value of the used syringe unsettles the boundaries between subject and object, private and public, and space and place. This has implications for how we understand not just the space of the shooting gallery but the politics of harm reduction and the city.
The Political Psychology of (de)Securitization: Place-Making Strategies in Denmark, Sweden, and Canada
Authors: Kinnvall Catarina , Nesbitt-Larking Paul
Published: August 2010

In this article we demonstrate how both state structures and collective agencies contribute to patterns of securitization and, in so doing, reconfigure conceptions of space and place. Focusing on the life-chances of Muslim minority populations in Denmark, Sweden, and Canada, we begin by establishing how experiences of empire and colonization have shaped dominant regimes of citizenship and multiculturalism. Analyzing responses to the Danish newspaper publication of the ‘Mohammed cartoons’, we illustrate the dynamics of place making that are operative in the political psychology of securitization. Our analysis illustrates the cosmopolitical and dialogical character of Canadian multiculturalism and how such a regime facilitates a politics of space that is distinct from the cartographies of imperialism that inform place making in Denmark and, to a lesser extent, Sweden.
On the Role of Affect and Practice in the Production of Place
Authors: Duff Cameron
Published: August 2010

Michel de Certeau's account of the modern city emphasises the ‘doing’ and ‘making’ residents undertake in an attempt to render a city more amenable to an ‘art’ of resistance. Yet, in attending to this doing and making, de Certeau has largely ignored the felt and affective dimensions of city life. Edward Casey provides a compelling means of interrogating these affective dimensions, distinguishing ‘thick’ and ‘thin’ places in everyday life. Thick places are contrived in the imbrications of affect, habit, and practice, presenting opportunities for personal enrichment and a deepening of affective experience. Casey's work restores the affective fecundity of place, even if it fails to provide a clear sense of how thick places might be identified. This paper takes up this challenge in an attempt to clarify the role of affect and practice in the production of place. The paper first reviews the practical and affective dimensions of this place-making before turning to an ethnographic account of young people, place, and urban life recently completed in Vancouver, Canada. This study explored the ways young people negotiate and transform place and the impact these practices have on the characteristic orientations of self and belonging. The experience of place was found to involve a series of affective relays between the cultivation of private places and the negotiation of designated spaces. The affective atmospheres created in these exchanges helped participants transform thin or designated spaces into dynamic thick places. The paper closes with a discussion of the role thick places might play in the design of innovative youth development efforts in urban settings.
Single-molecule derivation of salt dependent base-pair free energies in DNA
Authors: Huguet Josep M. , Bizarro Cristiano V. , Forns Núria , Smith Steven B. , Bustamante Carlos , Ritort Felix
Published: August 2010

Accurate knowledge of the thermodynamic properties of nucleic acids is crucial to predicting their structure and stability. To date most measurements of base-pair free energies in DNA are obtained in thermal denaturation experiments, which depend on several assumptions. Here we report measurements of the DNA base-pair free energies based on a simplified system, the mechanical unzipping of single DNA molecules. By combining experimental data with a physical model and an optimization algorithm for analysis, we measure the 10 unique nearest-neighbor base-pair free energies with 0.1 kcal mol
-1
precision over two orders of magnitude of monovalent salt concentration. We find an improved set of standard energy values compared with Unified Oligonucleotide energies and a unique set of 10 base-pair-specific salt-correction values. The latter are found to be strongest for AA/TT and weakest for CC/GG. Our unique energy values and salt corrections improve predictions of DNA unzipping forces and are fully compatible with melting temperatures for oligos. The method should make it possible to obtain free energies, enthalpies, and entropies in conditions not accessible by bulk methodologies.
Sector Variations in SMEs’ Use of External Business Advice
Authors: Webber D.J. , Johnson S. , Fargher S.
Published: August 2010

This paper uses employer survey data to identify whether and why the probability that a firm uses external advice varies across sectors. The results suggest that the probability of a firm using external advice does vary across sectors and these sector differences can be explained by differences in inherent problems, managerial aspirations and location. Policy makers should not be sector-blind when encouraging firms to use external advice.
Systematic Formative Research to Develop HIV Prevention Messages for People Living with HIV
Authors: Uhrig Jennifer , Eroğlu Doğan , Bann Carla , Wasserman Jill L , Guenther-Grey Carolyn
Published: August 2010

Systematic formative research is vital to the successful development of health communication and marketing messages targeting people living with HIV (PLWH). The purpose of this study was to use a systematic process to develop and pretest HIV prevention messages for PLWH. We conducted our study in three phases with findings from each phase informing the development of the subsequent phase. In Phase 1, we employed idea-generation techniques in group settings with PLWH and HIV prevention experts to elicit a comprehensive list of HIV prevention strategies and persuasive arguments for these strategies. In Phase 2, we conducted focus groups and in-depth interviews with PLWH to evaluate the messages that emerged in Phase 1. In Phase 3, we administered a structured survey instrument to PLWH to quantitatively evaluate audience reactions and receptivity to the 19 most promising messages from Phase 2. By Phase 3, the majority of participants agreed with evaluative statements that expressed favorable attitudes toward the messages. These results support the utility of systematic efforts to generate and screen messages prior to large-scale testing.
Pacing pattern and performance during the 2008 Olympic rowing regatta
Authors: Muehlbauer Thomas , Schindler Christian , Widmer Alexander
Published: August 2010

Data from the 2008 Olympic rowing regatta were analysed to determine the time distribution during races and to assess whether pacing patterns differ between heats and the corresponding finals. Absolute and relative sector times for all of the four 500 m race quarters were analysed, for all boats in all heavyweight heats and final races (n=72 boats for men, n=60 boats for women). Irrespective of race type, boat rank or boat type, analyses of variance with repeated measures revealed that absolute times in the second and/or third race quarter(s) were significantly (both sexes: P<0.001) longer than those either in the first or final quarter, resulting in a parabolic‐shaped profile. Compared with the heats, the pacing pattern adopted during the finals was significantly different (females: P<0.013; males: P<0.001); that is, relatively slower in the first and second race quarter but relatively faster in the last quarter. The parabolic‐shaped race profile indicates an anticipatory control of speed and energy distribution over the course of the 2000‐m race. The observed changes in pacing pattern suggest that during the finals a more conservative starting pace is used, which could be physiologically advantageous, because some energy is withheld for the final spurt.
Glycaemic, insulinaemic, and immune responses to commercially available beverages consumed during recovery from rowing training
Authors: Macdonald Sara L. , Perry Tracy L. , Rose Meredith C.
Published: August 2010

The consumption of carbohydrate and protein after exercise improves muscle glycogen synthesis and attenuates the decrease in immune function seen with endurance‐type exercise. However, the impact of consuming commercially available beverages on glycaemic, insulinaemic, and immune responses during recovery from rowing training has not been investigated. Twenty‐one male and female rowers completed four trials in a randomized order. Commercially available beverages were consumed in volumes providing 1.2 g carbohydrate · kg−1 body mass, upon completion of ~90 min of rowing at 60–70% maximum oxygen uptake, interspersed with up to five 5‐min intervals at or above race pace. Blood samples were taken before and 15, 30, 45, 60, 90, and 120 min after consumption of the beverages for analysis of insulin and glucose and at 90 and 360 min for the analysis of cortisol and interleukin‐6 (IL‐6). The high‐carbohydrate sports beverage and the meal replacement beverage produced a significantly larger (P<0.05) glucose incremental area under the curve than the sports‐specific meal replacement beverage or the flavoured milk beverage. The high‐carbohydrate sports beverage and the sports‐specific meal replacement beverage produced a significantly lower (P<0.05) insulin incremental area under the curve than the meal replacement beverage or the flavoured milk beverage. The meal replacement beverage produced both a high glycaemic and insulinaemic response, suggesting that it may produce a higher rate of muscle glycogen resynthesis. There was a significant interaction between time and beverage for IL‐6 (P=0.001), but not for cortisol (P=0.779). These results indicate that the impact of post‐exercise nutrition on immune response may not be exclusively mediated by an attenuation of the cortisol response.
Livestock production: recent trends, future prospects
Authors: Thornton Philip K.
Published: August 2010

The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades.
Urbanization and its implications for food and farming
Authors: Satterthwaite David , McGranahan Gordon , Tacoli Cecilia
Published: August 2010

This paper discusses the influences on food and farming of an increasingly urbanized world and a declining ratio of food producers to food consumers. Urbanization has been underpinned by the rapid growth in the world economy and in the proportion of gross world product and of workers in industrial and service enterprises. Globally, agriculture has met the demands from this rapidly growing urban population, including food that is more energy-, land-, water- and greenhouse gas emission-intensive. But hundreds of millions of urban dwellers suffer under-nutrition. So the key issues with regard to agriculture and urbanization are whether the growing and changing demands for agricultural products from growing urban populations can be sustained while at the same time underpinning agricultural prosperity and reducing rural and urban poverty. To this are added the need to reduce greenhouse gas emissions and to build resilience in agriculture and urban development to climate change impacts. The paper gives particular attention to low- and middle-income nations since these have more than three-quarters of the world's urban population and most of its largest cities and these include nations where issues of food security are most pressing.
Managing uncertainty: a review of food system scenario analysis and modelling
Authors: Reilly Michael , Willenbockel Dirk
Published: August 2010

Complex socio-ecological systems like the food system are unpredictable, especially to long-term horizons such as 2050. In order to manage this uncertainty, scenario analysis has been used in conjunction with food system models to explore plausible future outcomes. Food system scenarios use a diversity of scenario types and modelling approaches determined by the purpose of the exercise and by technical, methodological and epistemological constraints. Our case studies do not suggest Malthusian futures for a projected global population of 9 billion in 2050; but international trade will be a crucial determinant of outcomes; and the concept of sustainability across the dimensions of the food system has been inadequately explored so far. The impact of scenario analysis at a global scale could be strengthened with participatory processes involving key actors at other geographical scales. Food system models are valuable in managing existing knowledge on system behaviour and ensuring the credibility of qualitative stories but they are limited by current datasets for global crop production and trade, land use and hydrology. Climate change is likely to challenge the adaptive capacity of agricultural production and there are important knowledge gaps for modelling research to address.
Implications of climate change for agricultural productivity in the early twenty-first century
Authors: Gornall Jemma , Betts Richard , Burke Eleanor , Clark Robin , Camp Joanne , Willett Kate , Wiltshire Andrew
Published: August 2010

This paper reviews recent literature concerning a wide range of processes through which climate change could potentially impact global-scale agricultural productivity, and presents projections of changes in relevant meteorological, hydrological and plant physiological quantities from a climate model ensemble to illustrate key areas of uncertainty. Few global-scale assessments have been carried out, and these are limited in their ability to capture the uncertainty in climate projections, and omit potentially important aspects such as extreme events and changes in pests and diseases. There is a lack of clarity on how climate change impacts on drought are best quantified from an agricultural perspective, with different metrics giving very different impressions of future risk. The dependence of some regional agriculture on remote rainfall, snowmelt and glaciers adds to the complexity. Indirect impacts via sea-level rise, storms and diseases have not been quantified. Perhaps most seriously, there is high uncertainty in the extent to which the direct effects of CO
2
rise on plant physiology will interact with climate change in affecting productivity. At present, the aggregate impacts of climate change on global-scale agricultural productivity cannot be reliably quantified.
Aquaculture: global status and trends
Authors: Bostock John , McAndrew Brendan , Richards Randolph , Jauncey Kim , Telfer Trevor , Lorenzen Kai , Little David , Ross Lindsay , Handisyde Neil , Gatward Iain , Corner Richard
Published: August 2010

Aquaculture contributed 43 per cent of aquatic animal food for human consumption in 2007 (e.g. fish, crustaceans and molluscs, but excluding mammals, reptiles and aquatic plants) and is expected to grow further to meet the future demand. It is very diverse and, contrary to many perceptions, dominated by shellfish and herbivorous and omnivorous pond fish either entirely or partly utilizing natural productivity. The rapid growth in the production of carnivorous species such as salmon, shrimp and catfish has been driven by globalizing trade and favourable economics of larger scale intensive farming. Most aquaculture systems rely on low/uncosted environmental goods and services, so a critical issue for the future is whether these are brought into company accounts and the consequent effects this would have on production economics. Failing that, increased competition for natural resources will force governments to allocate strategically or leave the market to determine their use depending on activities that can extract the highest value. Further uncertainties include the impact of climate change, future fisheries supplies (for competition and feed supply), practical limits in terms of scale and in the economics of integration and the development and acceptability of new bio-engineering technologies.

In the medium term, increased output is likely to require expansion in new environments, further intensification and efficiency gains for more sustainable and cost-effective production. The trend towards enhanced intensive systems with key monocultures remains strong and, at least for the foreseeable future, will be a significant contributor to future supplies. Dependence on external feeds (including fish), water and energy are key issues. Some new species will enter production and policies that support the reduction of resource footprints and improve integration could lead to new developments as well as reversing decline in some more traditional systems.
The future of the global food system
Authors: Godfray H. Charles J. , Crute Ian R. , Haddad Lawrence , Lawrence David , Muir James F. , Nisbett Nicholas , Pretty Jules , Robinson Sherman , Toulmin Camilla , Whiteley Rosalind
Published: August 2010

Although food prices in major world markets are at or near a historical low, there is increasing concern about food security—the ability of the world to provide healthy and environmentally sustainable diets for all its peoples. This article is an introduction to a collection of reviews whose authors were asked to explore the major drivers affecting the food system between now and 2050. A first set of papers explores the main factors affecting the demand for food (population growth, changes in consumption patterns, the effects on the food system of urbanization and the importance of understanding income distributions) with a second examining trends in future food supply (crops, livestock, fisheries and aquaculture, and ‘wild food’). A third set explores exogenous factors affecting the food system (climate change, competition for water, energy and land, and how agriculture depends on and provides ecosystem services), while the final set explores cross-cutting themes (food system economics, food wastage and links with health). Two of the clearest conclusions that emerge from the collected papers are that major advances in sustainable food production and availability can be achieved with the concerted application of current technologies (given sufficient political will), and the importance of investing in research sooner rather than later to enable the food system to cope with both known and unknown challenges in the coming decades.
The homeodomain protein hmbx-1 maintains asymmetric gene expression in adult C. elegans olfactory neurons
Authors: Lesch Bluma J. , Bargmann Cornelia I.
Published: August 2010

Differentiated neurons balance the need to maintain a stable identity with their flexible responses to dynamic environmental inputs. Here we characterize these opposing influences on gene expression in Caenorhabditis elegans olfactory neurons. Using transcriptional reporters that are expressed differentially in two olfactory neurons, AWCON and AWCOFF, we identify mutations that affect the long-term maintenance of appropriate chemoreceptor expression. A newly identified gene from this screen, the conserved transcription factor hmbx-1, stabilizes AWC gene expression in adult animals through dosage-sensitive interactions with its transcriptional targets. The late action of hmbx-1 complements the early role of the transcriptional repressor gene nsy-7: Both repress expression of multiple AWCOFF genes in AWCON neurons, but they act at different developmental stages. Environmental signals are superimposed onto this stable cell identity through at least two different transcriptional pathways that regulate individual chemoreceptor genes: a cGMP pathway regulated by sensory activity, and a daf-7 (TGF-β)/daf-3 (SMAD repressor) pathway regulated by specific components of the density-dependent C. elegans dauer pheromone.