bluuebunny/crossref_metadata_2025 huggingface dataset:
Sheltered sandy beaches of southwestern Australia
Authors: Travers A. , Eliot M. J. , Eliot I. G. , Jendrzejczak M.
Published: November 2010

Four beach types were identified from field surveys of beach profiles on low-energy sandy beaches in Cockburn Sound, a micro-tidal, semi-enclosed basin in southwestern Australia. These were delineated by an exposure factor (Ef), which provided a surrogate for the relationship between incident wave energy and attenuation as a result of structures, banks and shoals. The four beach profiles identified were exponential, segmented, concave-curvilinear and convex-curvilinear in form. Whether the different profile shapes occurred in environments subject to different degrees of sheltering and protection under the same tidal regime was open to question. Beach profiles were examined for Como Beach and Princess Royal Harbour in Western Australia and compared with observations from Cockburn Sound to test this proposition. Cockburn Sound and Princess Royal Harbour are subject to minimal penetration of swell waves whereas Como Beach, in the Swan River Estuary, is wholly fetch limited. Profile forms identified in each environment were consistent with those described from Cockburn Sound. Similar profile types had similar exposure values for all sites such that Ef<1 was characteristic of exponential profiles, 1–1.5 of segmented, 1.5–2 of concave-curvilinear, and Ef>2 of convex-curvilinear. Although this approach requires further testing in low-energy environments subject to different tidal ranges and fluctuations in sea level, use of the exposure factor for delineation of low-energy sheltered beach types appears to be a robust procedure.
The Australian desert dunefields: formation and evolution in an old, flat, dry continent
Authors: Hesse Paul P.
Published: November 2010

A new map, the first based on interpretation of satellite imagery, reveals both the complexity of Australia's dunefields and their relationships with topography, climate and substrate. Of the five main sand seas, the Mallee, Strzelecki and Simpson in eastern Australia cover Quaternary sedimentary basins whereas the Great Victoria and Great Sandy dunefields in the west are formed by reworking of valley and piedmont sediments in a non-basinal landscape of low-relief ridge and valley topography. These dunefields cover large areas of the arid zone and semi-arid zone and small areas of dunes in sub-humid areas around the margins of the continent reflecting past expansion of arid climates during glacial stages of the last several glacial cycles. Several areas of low relief stand out as being largely dune-free: the limestone Nullarbor Plain, clay plains of the Georgina Basin and floodplains of rivers in the Carpentaria, Lake Eyre and Murray–Darling drainage basins where sand is rare or not transported by diminished Late Quaternary rivers. The Yilgarn Block of southwestern Australia is also surprisingly free of dunes, possibly as a result of long, deep weathering. Everywhere the history of climate change is evident in dune morphology and distribution, including large areas where the sand dune orientations are markedly divergent from modern sand moving wind directions.
FPGA-Array with Bandwidth-Reduction Mechanism for Scalable and Power-Efficient Numerical Simulations Based on Finite Difference Methods
Authors: Sano Kentaro , Luzhou Wang , Hatsuda Yoshiaki , Iizuka Takanori , Yamamoto Satoru
Published: November 2010

For scientific numerical simulation that requires a relatively high ratio of data access to computation, the scalability of memory bandwidth is the key to performance improvement, and therefore custom-computing machines (CCMs) are one of the promising approaches to provide bandwidth-aware structures tailored for individual applications. In this article, we propose a scalable FPGA-array with bandwidth-reduction mechanism (BRM) to implement high-performance and power-efficient CCMs for scientific simulations based on finite difference methods. With the FPGA-array, we construct a systolic computational-memory array (SCMA), which is given a minimum of programmability to provide flexibility and high productivity for various computing kernels and boundary computations. Since the systolic computational-memory architecture of SCMA provides scalability of both memory bandwidth and arithmetic performance according to the array size, we introduce a homogeneously partitioning approach to the SCMA so that it is extensible over a 1D or 2D array of FPGAs connected with a mesh network. To satisfy the bandwidth requirement of inter-FPGA communication, we propose BRM based on time-division multiplexing. BRM decreases the required number of communication channels between the adjacent FPGAs at the cost of delay cycles. We formulate the trade-off between bandwidth and delay of inter-FPGA data-transfer with BRM. To demonstrate feasibility and evaluate performance quantitatively, we design and implement the SCMA of 192 processing elements over two ALTERA Stratix II FPGAs. The implemented SCMA running at 106MHz has the peak performance of 40.7 GFlops in single precision. We demonstrate that the SCMA achieves the sustained performances of 32.8 to 35.7 GFlops for three benchmark computations with high utilization of computing units. The SCMA has complete scalability to the increasing number of FPGAs due to the highly localized computation and communication. In addition, we also demonstrate that the FPGA-based SCMA is power-efficient: it consumes 69% to 87% power and requires only 2.8% to 7.0% energy of those for the same computations performed by a 3.4-GHz Pentium4 processor. With software simulation, we show that BRM works effectively for benchmark computations, and therefore commercially available low-end FPGAs with relatively narrow I/O bandwidth can be utilized to construct a scalable FPGA-array.
Post-Thrombolytic Hyperglycemia and 3-Month Outcome in Acute Ischemic Stroke
Authors: Putaala Jukka , Sairanen Tiina , Meretoja Atte , Lindsberg Perttu J. , Tiainen Marjaana , Liebkind Ron , Strbian Daniel , Atula Sari , Artto Ville , Rantanen Kirsi , Silvonen Pyry , Piironen Katja , Curtze Sami , Häppölä Olli , Mustanoja Satu , Pitkäniemi Janne , Salonen Oili , Silvennoinen Heli , Soinne Lauri , Kuisma Markku , Tatlisumak Turgut , Kaste Markku
Published: November 2010

Background: Treating hyperglycemia in acute ischemic stroke may be beneficial, but knowledge on its prognostic value and optimal target glucose levels is scarce. We investigated the dynamics of glucose levels and the association of hyperglycemia with outcomes on admission and within 48 h after thrombolysis. Methods: We included 851 consecutive patients with acute ischemic stroke treated with intravenous thrombolysis in the Helsinki University Central Hospital during 1998–2008. Outcome measures were unfavorable 3- month outcome (3–6 on the modified Rankin Scale), death, and symptomatic intracerebral hemorrhage (sICH) according to NINDS criteria. Hyperglycemia was defined as a blood glucose level of ≧8.0 mmol/l. Four groups were identified based on (a) admission and (b) peak glucose levels 48 h after thrombolysis: (1) persistent normoglycemia (baseline plus 48-hour normoglycemia), (2) baseline hyperglycemia (48-hour normoglycemia), (3) 48-hour hyperglycemia (baseline normoglycemia), and (4) persistent hyperglycemia (baseline plus 48-hour hyperglycemia). Results: 480 (56.4%) of our patients (median age 70 years; onset-to-needle time 199 min; National Institutes of Health Stroke Scale score 9), had persistent normoglycemia, 59 (6.9%) had baseline hyperglycemia, 175 (20.6%) had 48-hour hyperglycemia, while persistent hyperglycemia appeared in 137 (16.1%) patients. Persistent and 48-hour hyperglycemia independently predicted unfavorable outcome [odds ratio (OR) = 2.33, 95% confidence interval (CI) = 1.41–3.86, and OR = 2.17, 95% CI = 1.30–3.38, respectively], death (OR = 6.63, 95% CI = 3.25–13.54, and OR = 3.13, 95% CI = 1.56–6.27, respectively), and sICH (OR = 3.02, 95% CI = 1.68–5.43, and OR = 1.89, 95% CI = 1.04–3.43, respectively), whereas baseline hyperglycemia did not. Conclusions: Hyperglycemia (≧8.0 mmol/l) during 48 h after intravenous thrombolysis of ischemic stroke is strongly associated with unfavorable outcome, sICH, and death.
Associations between Gender, Ocular Parameters and Diseases: The Beijing Eye Study
Authors: Xu Liang , You Qi Sheng , Wang Ya Xing , Jonas Jost B.
Published: November 2010

Background: To assess relationships between gender, ocular parameters and ocular diseases. Methods: The Beijing Eye Study is a population-based study including 4,439 Chinese. All participants underwent a detailed ophthalmic examination, anthropometric measurements and analytic blood examinations. Results: In multivariate regression analysis, female gender was significantly associated with a shallower anterior chamber (p < 0.001) and narrower anterior chamber angle (p = 0.001), higher prevalence of dry eye (p = 0.002), lower best-corrected visual acuity (p = 0.04) and lower presenting visual acuity (p = 0.046), and with the systemic parameters of lower educational level (p < 0.001), rural region (p = 0.002), lower frequency of smoking (p < 0.001) and alcohol consumption (p < 0.001), lower body height (p < 0.001), lower diastolic blood pressure (p < 0.001) and higher systolic blood pressure (p < 0.001), and higher serum concentrations of triglycerides (p = 0.005), low-density lipoproteins (p < 0.001) and high-density lipoproteins (p < 0.001). Men and women did not vary significantly in refractive error, intraocular pressure, central corneal thickness, size of the optic disk and parapapillary atrophy, and prevalences of retinal microvascular abnormalities, trachoma, pterygia, nuclear cataract, posterior subcapsular or cortical cataract, angle-closure glaucoma, open-angle glaucoma, age-related macular degeneration and retinal vein occlusions. Conclusions: After controlling for systemic factors, females have a shallower anterior chamber, a narrower anterior chamber angle and a higher prevalence of dry eye.
Relative Validity and Reproducibility of a Food Frequency Questionnaire Designed for French Adults
Authors: Kesse-Guyot Emmanuelle , Castetbon Katia , Touvier Mathilde , Hercberg Serge , Galan Pilar
Published: November 2010

Objectives/Aims: We tested the reproducibility and relative validity of a French self-administered food frequency questionnaire (FFQ) against 24-hour dietary records (DRs). Methods: We selected 140 participants from the SU.VI.MAX study. They filled in the FFQ twice at 1-year intervals and completed monthly 24-hour DR during that year. The number of food items in the FFQ was 240. Results: Reproducibility was high. Medians of Pearson coefficients were 0.70 and 0.65 for nutrients in men and women, respectively. Medians of intraclass correlation coefficients for food were 0.62 in men and 0.65 in women. For nutrients, crude Pearson correlation coefficients for relative validity ranged from 0.28 to 0.67 in men and from 0.25 to 0.55 in women. The Spearman coefficient for alcohol was 0.78 in both genders. For food, the medians of the Spearman coefficient were 0.49 and 0.45 for men and women, respectively. Complete disagreement between the FFQ and 24-hour DRs for ranking subjects according to food consumption was low (about 4%), except for rarely consumed food groups, that is nuts, legumes and offal. Calibration coefficients were estimated by linear regression. All coefficients were lower than one. Conclusions: Acceptable reproducibility and relative validity were observed in a FFQ designed for French adults.
Fatal Cerebral Air Embolism following Uneventful Flexible Bronchoscopy
Authors: Azzola Andrea , von Garnier Christophe , Chhajed Prashant N. , Schirp Udo , Tamm Michael
Published: November 2010

Flexible bronchoscopy is a widely used and safe procedure with a reported maximal mortality rate of 0.04% and a major-complications rate of 0.5%. There are, however, only few case descriptions for postinterventional cerebral air embolism and the frequency of this supposedly rare complication is unknown. The current study presents 2 patients with non-small cell lung cancer who suffered fatal cerebral air embolism following diagnostic bronchoscopy with transbronchial needle aspiration and transbronchial biopsy, resulting in a frequency of <0.02% for this severe complication in our institution. In addition to early supportive measures, 1 patient received hyperbaric oxygen therapy as further treatment. Prompt recognition of this complication is mandatory in order to implement appropriate supportive measures. High-flow oxygen should be administered and hyperbaric oxygen therapy may be considered, if available. If possible, positive pressure ventilation should be avoided.
Stroke Characteristics in Patients with Pretreated Arterial Hypertension
Authors: De Reuck J.
Published: November 2010

Background: Arterial hypertension (AH) is one of the most important vascular risk factors for stroke that can be treated. The present retrospective study analyses the influence of pretreated AH on the outcome of patients with ischaemic and haemorrhagic strokes, compared to those with normal blood pressure (BP). Patients and Methods: The demographic features, vascular risk factors, stroke type, stroke severity (according to the National Institutes of Health Stroke scale) and disability (according to the modified Rankin scale) were compared between 806 pretreated hypertensive patients and 320 ones with normal BP. Results: The incidence and the severity of the ischaemic strokes were similar but the outcome was worse in patients with pretreated AH compared to those with normal BP. In the former patients, coronary artery disease and isolated atrial fibrillation were found as confounders on multivariate analysis. The incidence, the severity and the outcome of patients with a haemorrhagic stroke were similar in both groups. Conclusions: The outcome in ischaemic stroke is worse in pretreated AH patients, compared to normotensive ones, probably due to the higher incidence of other associated vascular risk factors. Pretreated AH improves the outcome of patients with a haemorrhagic stroke.
First Analysis of the Relation Between
CYP2C19
Genotype and Pharmacodynamics in Patients Treated With Ticagrelor Versus Clopidogrel
Authors: Tantry Udaya S. , Bliden Kevin P. , Wei Cheryl , Storey Robert F. , Armstrong Martin , Butler Kathleen , Gurbel Paul A.
Published: November 2010

Background—

The influence of cytochrome P450 (CYP)
2C19
genotype on platelet function in patients treated with ticagrelor versus clopidogrel is unknown.

Methods and Results—

CYP2C19
(*1, *2, *3, *4, *5, *6, *7, *8, *17) genotyping was performed in patients with coronary artery disease treated with ticagrelor (180-mg load, 90 mg BID) (n=92) or clopidogrel (600-mg load, 75 mg/d) (n=82). All patients received 75 to 100 mg/d aspirin. Platelet function was measured by aggregometry, VerifyNow P2Y12 assay, and vasodilator-stimulated phosphoprotein-phosphorylation assay at predose, 8 hours postloading, and maintenance. In each treatment group, patients were categorized according to
2C19
genotype carrier status (loss-of-function, gain-of-function) and metabolizer status. Kruskal-Wallis test was used to compare platelet function among these categories for each treatment, and Wilcoxon rank sum test was used to compare platelet function between the clopidogrel and ticagrelor groups for each category. There was no statistically significant influence of genotype on platelet function during aspirin therapy alone. Ticagrelor exhibited lower platelet reactivity than clopidogrel by all assays irrespective of
2C19
genotype or metabolizer status (
P
<0.01). Loss-of-function carriers had greater platelet reactivity during clopidogrel therapy. The influence of genotype on platelet reactivity was greatest during clopidogrel maintenance and best demonstrated by the VerifyNow P2Y12 assay.

Conclusions—

This report is the first to demonstrate the superior pharmacodynamic effect of ticagrelor compared with clopidogrel irrespective of
CYP2C19
genotype. Whereas
CYP2C19
genotype influenced the antiplatelet effect of clopidogrel, there was no effect of
CYP2C19
genotype during ticagrelor therapy.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifiers: NCT00642811 and NCT00528411.
Intracoronary Versus Intravenous Administration of Abciximab in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention With Thrombus Aspiration
Authors: Gu Youlan L. , Kampinga Marthe A. , Wieringa Wouter G. , Fokkema Marieke L. , Nijsten Maarten W. , Hillege Hans L. , van den Heuvel Ad F.M. , Tan Eng-Shiong , Pundziute Gabija , van der Werf Rik , Hoseyni Guyomi Siyrous , van der Horst Iwan C.C. , Zijlstra Felix , de Smet Bart J.G.L.
Published: November 2010

Background—

Administration of the glycoprotein IIb/IIIa inhibitor abciximab is an effective adjunctive treatment strategy during primary percutaneous coronary intervention for ST-segment elevation myocardial infarction. Although small-scale studies have suggested beneficial effects of intracoronary over intravenous administration of abciximab, this has not been investigated in a medium-scale randomized clinical trial.

Methods and Results—

A total of 534 ST-segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention with thrombus aspiration within 12 hours of symptom onset were randomized to either an intracoronary or an intravenous bolus of abciximab (0.25 mg/kg). Patients were pretreated with aspirin, heparin, and clopidogrel. The primary end point was the incidence of restored myocardial reperfusion, defined as complete ST-segment resolution. Secondary end points included myocardial reperfusion as assessed by myocardial blush grade, enzymatic infarct size, and major adverse cardiac events at 30 days. The incidence of complete ST-segment resolution was similar in the intracoronary and intravenous groups (64% versus 62%;
P
=0.562). However, the incidence of myocardial blush grade 2/3 was higher in the intracoronary group than in the intravenous group (76% versus 67%;
P
=0.022). Furthermore, enzymatic infarct size was smaller in the intracoronary than in the intravenous group (
P
=0.008). The incidence of major adverse cardiac events was similar in both groups (5.5% versus 6.1%;
P
=0.786).

Conclusions—

In ST-segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention with thrombus aspiration, intracoronary administration of abciximab compared with intravenous administration does not improve myocardial reperfusion as assessed by ST-segment resolution. However, intracoronary administration is associated with improved myocardial reperfusion as assessed by myocardial blush grade and a smaller enzymatic infarct size.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00927615.
Novel Chemical Suppressors of Long QT Syndrome Identified by an In Vivo Functional Screen
Authors: Peal David S. , Mills Robert W. , Lynch Stacey N. , Mosley Janet M. , Lim Evi , Ellinor Patrick T. , January Craig T. , Peterson Randall T. , Milan David J.
Published: November 2010

Background—

Genetic long QT (LQT) syndrome is a life-threatening disorder caused by mutations that result in prolongation of cardiac repolarization. Recent work has demonstrated that a zebrafish model of LQT syndrome faithfully recapitulates several features of human disease, including prolongation of ventricular action potential duration, spontaneous early afterdepolarizations, and 2:1 atrioventricular block in early stages of development. Because of their transparency, small size, and absorption of small molecules from their environment, zebrafish are amenable to high-throughput chemical screens. We describe a small-molecule screen using the zebrafish
KCNH2
mutant
breakdance
to identify compounds that can rescue the LQT type 2 phenotype.

Methods and Results—

Zebrafish
breakdance
embryos were exposed to test compounds at 48 hours of development and scored for rescue of 2:1 atrioventricular block at 72 hours in a 96-well format. Only compounds that suppressed the LQT phenotype in 3 of 3 fish were considered hits. Screen compounds were obtained from commercially available small-molecule libraries (Prestwick and Chembridge). Initial hits were confirmed with dose-response testing and time-course studies. Optical mapping with the voltage-sensitive dye di-4 ANEPPS was performed to measure compound effects on cardiac action potential durations. Screening of 1200 small molecules resulted in the identification of flurandrenolide and 2-methoxy-N-(4-methylphenyl) benzamide (2-MMB) as compounds that reproducibly suppressed the LQT phenotype. Optical mapping confirmed that treatment with each compound caused shortening of ventricular action potential durations. Structure activity studies and steroid receptor knockdown suggest that flurandrenolide functions via the glucocorticoid signaling pathway.

Conclusions—

Using a zebrafish model of LQT type 2 syndrome in a high-throughput chemical screen, we have identified 2 compounds, flurandrenolide and the novel compound 2-MMB, as small molecules that rescue the zebrafish LQT type 2 syndrome by shortening the ventricular action potential duration. We provide evidence that flurandrenolide functions via the glucocorticoid receptor–mediated pathway. These 2 molecules and future discoveries from this screen should yield novel tools for the study of cardiac electrophysiology and may lead to novel therapeutics for human LQT patients.
Cryoablation Versus Radiofrequency Energy for the Ablation of Atrioventricular Nodal Reentrant Tachycardia (the CYRANO Study)
Authors: Deisenhofer Isabel , Zrenner Bernhard , Yin Yue-hui , Pitschner Heinz-Friedrich , Kuniss Malte , Großmann Georg , Stiller Sascha , Luik Armin , Veltmann Christian , Frank Julia , Linner Julia , Estner Heidi L. , Pflaumer Andreas , Wu Jinjin , von Bary Christian , Ücer Ekrem , Reents Tilko , Tzeis Stylianos , Fichtner Stephanie , Kathan Susanne , Karch Martin R. , Jilek Clemens , Ammar Sonia , Kolb Christof , Liu Zeng-Chang , Haller Bernhard , Schmitt Claus , Hessling Gabriele
Published: November 2010

Background—

Cryoablation has emerged as an alternative to radiofrequency catheter ablation (RFCA) for the treatment of atrioventricular (AV) nodal reentrant tachycardia (AVNRT). The purpose of this prospective randomized study was to test whether cryoablation is as effective as RFCA during both short-term and long-term follow-up with a lower risk of permanent AV block.

Methods and Results—

A total of 509 patients underwent slow pathway cryoablation (n=251) or RFCA (n=258). The primary end point was immediate ablation failure, permanent AV block, and AVNRT recurrence during a 6-month follow-up. Secondary end points included procedural parameters, device functionality, and pain perception. Significantly more patients in the cryoablation group than the RFCA group reached the primary end point (12.6% versus 6.3%;
P
=0.018). Whereas immediate ablation success (96.8% versus 98.4%) and occurrence of permanent AV block (0% versus 0.4%) did not differ, AVNRT recurrence was significantly more frequent in the cryoablation group (9.4% versus 4.4%;
P
=0.029). In the cryoablation group, procedure duration was longer (138±54 versus 123±48 minutes;
P
=0.0012) and more device problems occurred (13 versus 2 patients;
P
=0.033). Pain perception was lower in the cryoablation group (
P
<0.001).

Conclusions—

Cryoablation for AVNRT is as effective as RFCA over the short term but is associated with a higher recurrence rate at the 6-month follow-up. The risk of permanent AV block does not differ significantly between cryoablation and RFCA. The potential benefits of cryoenergy relative to ablation safety and pain perception are counterbalanced by longer procedure times, more device problems, and a high recurrence rate.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00196222.
Evaluation of the Second Generation of a Bioresorbable Everolimus Drug-Eluting Vascular Scaffold for Treatment of De Novo Coronary Artery Stenosis
Authors: Serruys Patrick W. , Onuma Yoshinobu , Ormiston John A. , de Bruyne Bernard , Regar Evelyn , Dudek Dariusz , Thuesen Leif , Smits Pieter C. , Chevalier Bernard , McClean Dougal , Koolen Jacques , Windecker Stephan , Whitbourn Robert , Meredith Ian , Dorange Cécile , Veldhof Susan , Miquel-Hebert Karine , Rapoza Richard , García-García Hector M.
Published: November 2010

Background—

The first generation of the bioresorbable everolimus drug-eluting vascular scaffold showed signs of shrinkage at 6 months, which largely contributed to late luminal loss. Nevertheless, late luminal loss was less than that observed with bare metal stents. To maintain the mechanical integrity of the device up to 6 months, the scaffold design and manufacturing process of its polymer were modified.

Methods and Results—

Quantitative coronary angiography, intravascular ultrasound with analysis of radiofrequency backscattering, and as an optional assessment, optical coherence tomography (OCT) were performed at baseline and at a 6-month follow-up. Forty-five patients successfully received a single bioresorbable everolimus drug-eluting vascular scaffold. One patient had postprocedural release of myocardial enzyme without Q-wave occurrence; 1 patient with OCT-diagnosed disruption of the scaffold caused by excessive postdilatation was treated 1 month later with a metallic drug-eluting stent. At follow-up, 3 patients declined recatheterization, 42 patients had quantitative coronary angiography, 37 had quantitative intravascular ultrasound, and 25 had OCT. Quantitative coronary angiography disclosed 1 edge restenosis (1 of 42; in-segment binary restenosis, 2.4%). At variance with the ultrasonic changes seen with the first generation of bioresorbable everolimus drug-eluting vascular scaffold at 6 months, the backscattering of the polymeric struts did not decrease over time, the scaffold area was reduced by only 2.0% with intravascular ultrasound, and no change was noted with OCT. On an intention-to-treat basis, the late lumen loss amounted to 0.19±0.18 mm with a limited relative decrease in minimal luminal area of 5.4% on intravascular ultrasound. OCT showed at follow-up that 96.8% of the struts were covered and that malapposition of at least 1 strut, initially observed in 12 scaffolds, was detected at follow-up in only 3 scaffolds. Mean neointimal growth measured by OCT between and on top of the polymeric struts equaled 1.25 mm
2
, or 16.6% of the scaffold area.

Conclusion—

Modified manufacturing process of the polymer and geometric changes in the polymeric platform have substantially improved the medium-term performance of this new generation of drug-eluting scaffold to become comparable to those of current drug eluting stents.

Clinical Trial Registration—

URL:
http://clinicaltrials.gov
. Unique identifier: NCT00856856.
Inhibition of Hyaluronan Synthesis Accelerates Murine Atherosclerosis
Authors: Nagy Nadine , Freudenberger Till , Melchior-Becker Ariane , Röck Katharina , ter Braak Michael , Jastrow Holger , Kinzig Martina , Lucke Susann , Suvorava Tatsiana , Kojda Georg , Weber Artur A. , Sörgel Fritz , Levkau Bodo , Ergün Süleyman , Fischer Jens W.
Published: November 2010

Background—

Hyaluronan is thought to mediate neointimal hyperplasia but also vasoprotection as an integral component of the endothelial glycocalyx. The present study addressed for the first time the effects of long-term pharmacological inhibition of hyaluronan synthesis on vascular function and atherosclerosis.

Methods and Results—

Four-week-old apolipoprotein E–deficient mice on a Western diet received orally an inhibitor of hyaluronan synthesis, 4-methylumbelliferone (4-MU; 10 mg/g body wt), resulting in 600 nmol/L 4-MU in plasma. As a result, aortic plaque burden was markedly increased at 25 weeks. Furthermore, acetylcholine-dependent relaxation of aortic rings was decreased and mean arterial blood pressure was increased in response to 4-MU. However, hydralazine blunted the hypertensive effect of 4-MU without inhibiting the proatherosclerotic effect. A photothrombosis model revealed a prothrombotic state that was not due to increased platelet activation or increased thrombin activation as monitored by CD62P expression and the endogenous thrombin potential. Importantly, increased recruitment of macrophages to vascular lesions was detected after 2 and 21 weeks of 4-MU treatment by immunohistochemistry, by intravital microscopy, and in a peritonitis model. As a potential underlying mechanism, severe damage of the endothelial glycocalyx after 2 and 21 weeks of treatment with 4-MU was detected by electron microscopy of the innominate artery and myocardial capillaries. Furthermore, 600 nmol/L 4-MU inhibited hyaluronan synthesis in cultured endothelial cells.

Conclusions—

The data suggest that systemic inhibition of hyaluronan synthesis by 4-MU interferes with the protective function of the endothelial glycocalyx, thereby facilitating leukocyte adhesion, subsequent inflammation, and progression of atherosclerosis.
Does Student Sorting Invalidate Value-Added Models of Teacher Effectiveness? An Extended Analysis of the Rothstein Critique
Authors: Koedel Cory , Betts Julian R.
Published: November 2010

Value-added modeling continues to gain traction as a tool for measuring teacher performance. However, recent research questions the validity of the value-added approach by showing that it does not mitigate student-teacher sorting bias (its presumed primary benefit). Our study explores this critique in more detail. Although we find that estimated teacher effects from some value-added models are severely biased, we also show that a sufficiently complex value-added model that evaluates teachers over multiple years reduces the sorting bias problem to statistical insignificance. One implication of our findings is that data from the first year or two of classroom teaching for novice teachers may be insufficient to make reliable judgments about quality. Overall, our results suggest that in some cases value-added modeling will continue to provide useful information about the effectiveness of educational inputs.
Primary Marine Aerosol Fluxes
Authors: Brooks Ian M. , Andreas Edgar L , McFiggans Gordon , Anguelova Magdalena D. , O'Dowd Colin
Published: November 2010

No Abstract available.
The Measurement Factors in Estimating Snowfall Derived from Snow Cover Surfaces Using Acoustic Snow Depth Sensors
Authors: Fischer Alexandre P.
Published: November 2010

At three Canadian test locations during the cold seasons of 2006 and 2007/08, snowfall measurements are derived from changes in the total depth of snow on the ground using multiple Campbell Scientific, Inc., SR50 ultrasonic ranging sensors over very short (minute–hour) time scales. Data analysis reveals that, because of the interplay of numerous essential factors that influence snow cover levels, the measurements exhibit a strong dependence on the time interval between consecutive measurements used to generate the snowfall value. This finding brings into question the reasonable accuracy of snowfall measurements that are derived from the snow cover surface using automated methods over very short time scales. In this study, two mathematical methods are developed to assist in quantifying the magnitude of the snowfall measurement error. From time-series analysis, the suggested characteristics of the snowdrift signal in the snow depth time series is shown by using measurements taken by FlowCapt Snowdrift acoustic sensors. Furthermore, the use of three collocated SR50s shows that repeated snow depth measurements represent three pairwise essentially different time series. These results question the reasonable accuracy of snowfall measurements derived using only a single ultrasonic ranging sensor, especially in cases in which the snow cover is redistributed by the wind and in which snow depth spatial variability is prominent.
The Cumulative Impact of Cloud Droplet Nucleating Aerosols on Orographic Snowfall in Colorado
Authors: Saleeby Stephen M. , Cotton William R. , Fuller Jamie D.
Published: November 2010

Hygroscopic pollution aerosols have the potential to alter winter orographic snowfall totals and spatial distributions by modification of high-elevation supercooled orographic clouds and the riming process. The authors investigate the cumulative effect of varying the concentrations of hygroscopic aerosols during January–February for four recent winter snowfall seasons over the high terrain of Colorado. Version 6.0 of the Regional Atmospheric Modeling System (RAMS) is used to determine the particular mountain ranges and seasonal conditions that are most susceptible. Multiple winter seasonal simulations are run at both 3- and 1-km horizontal grid spacing with varying aerosol vertical profiles. Model-predicted snowfall accumulation trends are compared with automated snow water equivalent observations at high-elevation sites. An increase in aerosol concentration leads to reduced riming of cloud water by ice particles within supercooled, liquid orographic clouds, thus leading to lighter rimed hydrometers with slower fall speeds and longer horizontal trajectories. This effect results in a spillover of snowfall from the windward slope to the leeward slope. A snowfall spillover effect is most evident in the southern and western regions of the San Juan Range where high-moisture-laden storms are more prevalent. The effect over the Park Range is also present in each simulated season, but with lower amplitudes and slightly varying magnitudes among seasons. Seasons with greater overall snowfall exhibit a greater response in magnitude and percentage change. The smallest spillover effect occurred downwind of the primary western slope mountain barriers. Although the aerosol effect on snowfall can be locally significant in particularly wet winter seasons, the interseasonal variability in synoptic conditions can impose much larger widespread changes in snowfall accumulation.
What is the Mechanism for the Modification of Convective Cloud Distributions by Land Surface–Induced Flows?
Authors: Garcia-Carreras Luis , Parker Douglas J. , Marsham John H.
Published: November 2010

The aim of this study is to determine the mechanism that modulates the initiation of convection within convergence zones caused by land surface–induced mesoscale flows. An idealized modeling approach linked quantitatively to observations of vegetation breezes over tropical Benin was used. A large-eddy model was used with a prescribed land surface describing heterogeneities between crop and forest over which vegetation breezes have been observed. The total surface fluxes were constant but the Bowen ratio varied with vegetation type. The heterogeneous land surface created temperature differences consistent with observations, which in turn forced mesoscale winds and convection at the convergence zones over the crop boundaries. At these convergence zones optimum conditions for the initiation of convection were found in the afternoon; the equivalent potential temperature was higher in the convergence zones than over anywhere else in the domain, due to reduced entrainment, and the mesoscale convergence produced a persistent increase in vertical wind velocities of up to 0.5 m s−1 over a 5–10-km region. The relative importance of these two mechanisms depended on the synoptic conditions. When convective inhibition was weak, the thermodynamic conditions at the convergence zone were most important, as the triggering of convection was easily accomplished. However, when the thermodynamic profile inhibited convection, the mesoscale updrafts became essential for triggering in order to break through the inhibiting barrier. At the same time, subsidence over the forest produced a warm capping layer over the boundary layer top that suppressed convection over the forest throughout the afternoon.
Variability of the Atlantic Meridional Mode during the Atlantic Hurricane Season
Authors: Smirnov Dimitry , Vimont Daniel J.
Published: November 2010

An observational and modeling study is conducted to investigate the structure of the Atlantic Meridional Mode (AMM) during the Atlantic hurricane season, and the relationship between AMM-related SST anomalies and environmental conditions that influence seasonal tropical cyclone activity. The observational analysis shows that during the Atlantic hurricane season the AMM exhibits a similar SST and low-level wind structure as during boreal spring (when the AMM is most active). Observed AMM SST variations are accompanied by air temperature and moisture anomalies that are limited to the boundary layer and an anomalous baroclinic circulation structure in the northern subtropical Atlantic with an anomalous lower-level cyclonic circulation residing under an anomalous upper-level anticyclone during a warm phase. This baroclinic structure contributes to a reduction in vertical wind shear over the tropical Atlantic that is dominated by changes in the upper-level flow.

Two sets of model experiments were conducted, in which the NCAR Community Atmospheric Model version 3.1 (CAM3.1) was coupled to a slab ocean model or a data ocean model. In each experiment, the model was either initialized with or forced by AMM-like SST anomalies during boreal summer. The simulations yielded a similar spatial structure to that in the observations, including the baroclinic atmospheric circulation and associated reduction in vertical wind shear. The similarity between the modeled and observed AMM structures strongly suggests a causal relationship in which the AMM-like SST anomalies are responsible for generating environmental conditions that can strongly influence seasonal tropical cyclone variability.
Understanding ENSO Regime Behavior upon an Increase in the Warm-Pool Temperature Using a Simple ENSO Model
Authors: Kim Baek-Min , An Soon-Il
Published: November 2010

The regime behavior of the low-order El Niño–Southern Oscillation (ENSO) model, according to an increase in the radiative–convective equilibrium sea surface temperature (SST; Tr), is studied to provide a possible explanation for the observed increase in ENSO irregularity characterized by decadal modulation. During recent decades, a clear increasing trend of the warm-pool SST has been observed. In this study, the increase in the warm-pool maximum SST is interpreted as an increase in Tr following previous studies. A bifurcation analysis with Tr as a control parameter is conducted to reveal that the degree of ENSO irregularity in the model is effectively controlled by the equilibrium states of the model. At a critical value of Tr, bifurcation analysis reveals that period-doubling bifurcation occurs and an amplitude-modulated ENSO emerges. At this point, a subcycle appears within the preexisting ENSO cycle, which initiates decadal modulation of ENSO. As Tr increases further, nested oscillations are successively generated, illustrating clear decadal modulation of ENSO. The qualitative regime changes revealed in this study are supported by the observation of regime shifts in the 1970s. With increasing Tr, the mean zonal SST gradient increases, and the model adjusts toward a “La Niña–like” mean state. Further constraint with shoaling of the mean thermocline depth and increasing stratification causes ENSO to exhibit stronger amplitude modulation. Furthermore, the timing of the period-doubling bifurcation advances with these two effects.
A Global View on the Wind Sea and Swell Climate and Variability from ERA-40
Authors: Semedo Alvaro , Sušelj Kay , Rutgersson Anna , Sterl Andreas
Published: November 2010

In this paper a detailed global climatology of wind-sea and swell parameters, based on the 45-yr European Centre for Medium-Range Weather Forecasts Re-Analysis (ERA-40) wave reanalysis is presented. The spatial pattern of the swell dominance of the earth’s oceans, in terms of the wave field energy balance and wave field characteristics, is also investigated. Statistical analysis shows that the global ocean is strongly dominated by swell waves. The interannual variability of the wind-sea and swell significant wave heights, and how they are related to the resultant significant wave height, is analyzed over the Pacific, Atlantic, and Indian Oceans. The leading modes of variability of wind sea and swell demonstrate noticeable differences, particularly in the Pacific and Atlantic Oceans. During the Northern Hemisphere winter, a strong north–south swell propagation pattern is observed in the Atlantic Ocean. Statistically significant secular increases in the wind-sea and swell significant wave heights are found in the North Pacific and North Atlantic Oceans.
Spatial and Temporal Transferability of a Distributed Energy-Balance Glacier Melt Model
Authors: MacDougall Andrew H. , Flowers Gwenn E.
Published: November 2010

Modeling melt from glaciers is crucial to assessing regional hydrology and eustatic sea level rise. The transferability of such models in space and time has been widely assumed but rarely tested. To investigate melt model transferability, a distributed energy-balance melt model (DEBM) is applied to two small glaciers of opposing aspects that are 10 km apart in the Donjek Range of the St. Elias Mountains, Yukon Territory, Canada. An analysis is conducted in four stages to assess the transferability of the DEBM in space and time: 1) locally derived model parameter values and meteorological forcing variables are used to assess model skill; 2) model parameter values are transferred between glacier sites and between years of study; 3) measured meteorological forcing variables are transferred between glaciers using locally derived parameter values; 4) both model parameter values and measured meteorological forcing variables are transferred from one glacier site to the other, treating the second glacier site as an extension of the first. The model parameters are transferable in time to within a <10% uncertainty in the calculated surface ablation over most or all of a melt season. Transferring model parameters or meteorological forcing variables in space creates large errors in modeled ablation. If select quantities (ice albedo, initial snow depth, and summer snowfall) are retained at their locally measured values, model transferability can be improved to achieve ≤15% uncertainty in the calculated surface ablation.
Causal attributions, pathway to care and clinical features of first-episode psychosis: A South African perspective
Authors: Burns Jonathan K. , Jhazbhay Khatija , Emsley Robin A.
Published: November 2010

Background: Causal belief systems and help-seeking practices may impact on pathway to care and features of first-episode psychosis (FEP) that have prognostic value. This is particularly relevant in South Africa where many people subscribe to traditional belief systems and consult traditional healers.

Aim: To evaluate the relationship between causal attributions and pathway to care and features of FEP that have prognostic value.

Method: We tested associations between causal attributions and pathway to care and duration of untreated psychosis (DUP), age of onset, PANSS-rated positive, negative and general symptoms and depressive symptoms (Calgary Depression Scale) in a sample of 54 FEP patients.

Results: Spiritual attribution of cause (49% of patients) was associated with long DUP, while consultation with a traditional healer (39% of patients) was associated with long DUP and high negative symptoms. Only 19% had consulted a psychiatrist. Seventy nine per cent (79%) were referred to hospital by family, police were involved in 44% of admissions, and 81% were admitted involuntarily.

Conclusions: Spiritual attributions of cause and previous consultation with traditional healers may delay entry to psychiatric care and thereby negatively impact on prognosis of FEP. This highlights the importance of mental health education and developing a positive collaborative relationship with traditional healers, especially in low- and middle-income countries.
Collective opinion and attitude dynamics dependency on informational and normative social influences
Authors: Huang Chung-Yuan , Tzou Pen-Jung , Sun Chuen-Tsai
Published: November 2010

In a continuous opinion dynamics model using a bounded confidence assumption, individuals can only influence each other’s opinions when those opinions are sufficiently close. However, we often observe real-world cases in which opinions are very different, yet individuals feel compelled to change their ideas to conform with their peers or superiors (or in rare cases, are willing to change them voluntarily). In other words, individuals tend to consider the practical value of conformity and worry about rejection if they do not adopt the opinions of the majority. To explore the influences of private acceptance of informational social influences and public compliance with normative social influences on collective opinion and attitude dynamics, we have created a model in which attitude and opinion respectively represent an agent’s private and expressed thoughts. Results from a series of simulation experiments indicate that our simplified model is as valid as previous opinion dynamics models also based on the bounded confidence assumption, but with different dynamics and outcomes regarding group opinion and attitude. To demonstrate our proposed model’s potential value and applications, we briefly discuss two issues of import to sociologists: pluralistic ignorance formation and destruction and minority influence.
Smoke and Mirrors
Authors: Chapman Tony
Published: November 2010

This article explores the potential of employing the concept of ‘cultural inertia’ to explain why areas are slow fully to recover from a period of industrial restructuring in polycentric urban regions. Cultural inertia produces and reproduces tolerances and intolerances to change. It is shown that taken-for-granted assumptions about what constrains progress in achieving recovery (in comparison with other areas) may actually be false. This article draws on a study of social and economic change in Tees Valley, a sub-region of North East England. It reports on 28 two-hour interviews and three focus groups with key stakeholders. It is concluded that catalytic change could come about in industrial restructuring areas, but only if stakeholders build on strengths. The danger lies in polycentric areas’ attempts to emulate metropolitan areas because of a fundamental lack of belief in existing strengths which can be exploited.
Simulating Urban Networks through Multiscalar Space-Time Dynamics: Europe and the United States, 17th-20th Centuries
Authors: Bretagnolle Anne , Pumain Denise
Published: November 2010

Simpop2 is a generic multi-agent model designed for simulating any system of cities. From an evolutionary theory built upon the observation of networks of cities in different parts of the world and over long time-periods, it has been possible to identify stylised facts that characterise their main features and properties. This paper presents data-oriented simulations of two kinds of system: in early settled countries (Europe, 1300—2000) and in countries more recently settled (the United States, 1650—2000). The model can simulate properly the general dynamics of urban systems, at different scales of observation (general configuration and trajectories of individual cities). The simulations help to identify some dynamic properties that are shared by both systems: a general growth trend and spatial expansion (produced through interurban competition which generates emulation towards innovation that explain the persistency of the hierarchical configuration); a dramatic increase of contrasts in city sizes since the first industrial revolution linked to the increase of communication speed; and, a differentiation of urban economic functions produced through interactions between cities and innovation cycles, as industrial revolution. The model also puts forward the necessary integration of a new urban function in the model, which represents the early emergence of global cities. Yet, beyond these similarities in the evolution of all urban systems, when they are fully integrated, the model also measures to what extent the observed peculiarities in their contemporary spatial and functional configuration depend on differences in the early space-filling process between the two kinds of system.