bluuebunny/crossref_metadata_2025 huggingface dataset:
A continuous mental task decreases the physiological response to soccer-specific intermittent exercise
Authors: Greig Matt , Marchant David , Lovell Richard , Clough Peter , McNaughton Lars
Published: May 2007

Background:

Epidemiological findings of higher injury incidence during the latter stages of soccer match-play have been attributed to fatigue.

Objective:

To examine the interaction of physical and cognitive responses during soccer-specific intermittent exercise.

Method:

Ten semi-professional soccer players completed a 90-minute laboratory-based treadmill protocol replicating the activity profile of soccer match-play. Two separate trials were performed in randomised order, with and without the added stressor of a continuous grid-based vigilance task. The exercise task comprised six repetitions of a 15 minute activity profile, separated by a passive 15 minute half-time interval. The vigilance task required continual attention and sporadic target response within a letter grid. Physical response (RPE, heart rate, blood lactate, salivary cortisol) and cognitive performance (response time, response accuracy) were quantified at 15 minute intervals.

Results:

Completing the exercise task with the vigilance task resulted in decreased physiological (heart rate, blood lactate) response. This may be attributed to externally directed attention, resulting in association with the cognitive task and subsequent dissociation from the physical effort. Response speed generally improved with exercise duration, while there was evidence of impaired accuracy in the early stages of the first half and the latter stages of the second half.

Conclusion:

The interaction of physical and mental work was not additive in nature. The mental task had a masking effect on the physical response. Performing physical exercise tasks without due regard for appropriate psychological stimuli may therefore overestimate the physiological response.
Subgrade stress ratios as airfield pavement rutting performance indicators
Authors: Gopalakrishnan Kasthurirangan , Thompson Marshall R
Published: May 2007

Rutting is a major distress in airport flexible pavements. Subgrade vertical strain criteria are used in many airport flexible pavement design procedures to consider the development of rutting. Several research studies have identified the limitations associated with these criteria. Design criteria based on subgrade stress ratios (SSRs) are being considered for evaluating subgrade rutting in airport flexible pavements. In this paper, the SSRs based on measured vertical subgrade stresses are related to surface rutting in flexible pavements subjected to repeated trafficking of Boeing 777 and 747 simulated test gears at the US Federal Aviation Administration (FAA) National Airport Pavement Test Facility (NAPTF). The results indicated overstressing of the subgrade in two test sections, and this was confirmed by trench study results. A good correlation was obtained between the SSRs and the surface rut depths, supporting the validity of developing SSR-based rutting transfer functions for airport flexible pavements serving the next generation of aircraft.Key words: rutting, subgrade stress ratio (SSR), National Airport Pavement Test Facility (NAPTF), pressure cell (PC), new generation aircraft, airport flexible pavement.
Level of visualization support for project communication in the Turkish construction industry: A quality function deployment approach
Authors: Nielsen Yasemin , Erdogan Bilge
Published: May 2007

Quality of communication is a key factor in the success of construction projects. Visualization technologies can play an important role in improving the quality of data by improving human comprehension and increasing the depth of the information delivered. Visualization has for some time been identified as one of the major technology themes allowing development of construction processes. However, visualization has not been embraced as a strategic tool by construction companies, and they generally fail to take full advantage of available visualization tools. This paper aims to evaluate the extent of visualization as a communication tool in the construction industry and to determine potential benefits to be gained through implementation of visualization. The current state of the use of visualization for communication in Turkish architecture, engineering, and construction companies is mapped through surveys and interviews. Information flow contents and types are analysed to determine the types of information in the construction process that may benefit from visual representation. According to the priorities of the expectations ranked by the users and the potential of different visualization tools, the level of visualization required for each data flow is determined by a quality function deployment (QFD) based approach.Key words: visualization, construction, visual communication, quality.
MINIMAL BELL–KOCHEN–SPECKER PROOFS WITH POVMs ON QUBITS
Authors: MÉTHOT ANDRÉ ALLAN
Published: May 2007

There are many different definitions of what a Bell–Kochen–Specker proof with POVMs might be. Here, we present and discuss the minimal proof on qubits for three of these definitions and show that they are indeed minimal.
Congenital Heart Disease and Other Heterotaxic Defects in a Large Cohort of Patients With Primary Ciliary Dyskinesia
Authors: Kennedy Marcus P. , Omran Heymut , Leigh Margaret W. , Dell Sharon , Morgan Lucy , Molina Paul L. , Robinson Blair V. , Minnix Susan L. , Olbrich Heike , Severin Thomas , Ahrens Peter , Lange Lars , Morillas Hilda N. , Noone Peadar G. , Zariwala Maimoona A. , Knowles Michael R.
Published: May 2007

Background—

Primary ciliary dyskinesia (PCD) is a recessive genetic disorder that is characterized by sinopulmonary disease and reflects abnormal ciliary structure and function. Situs inversus totalis occurs in ≈50% of PCD patients (Kartagener’s syndrome in PCD), and there are a few reports of PCD with heterotaxy (situs ambiguus), such as cardiovascular anomalies. Advances in diagnosis of PCD, such as genetic testing, allow the systematic investigation of this association.

Methods and Results—

The prevalence of heterotaxic defects was determined in 337 PCD patients by retrospective review of radiographic and ultrasound data. Situs solitus (normal situs) and situs inversus totalis were identified in 46.0% and 47.7% of patients, respectively, and 6.3% (21 patients) had heterotaxy. As compared with patients with situs solitus, those with situs abnormalities had more ciliary outer dynein arm defects, fewer inner dynein arm and central apparatus defects (
P
<0.001), and more mutations in ciliary outer dynein arm genes (
DNAI1
and
DNAH5
;
P
=0.022). Seven of 12 patients with heterotaxy who were genotyped had mutations in
DNAI1
or
DNAH5
. Twelve patients with heterotaxy had cardiac and/or vascular abnormalities, and most (8 of 12 patients) had complex congenital heart disease.

Conclusions—

At least 6.3% of patients with PCD have heterotaxy, and most of those have cardiovascular abnormalities. The prevalence of congenital heart disease with heterotaxy is 200-fold higher in PCD than in the general population (1:50 versus 1:10 000); thus, patients with PCD should have cardiac evaluation. Conversely, mutations in genes that adversely affect both respiratory and embryological nodal cilia are a significant cause of heterotaxy and congenital heart disease, and screening for PCD is indicated in those patients.
Major Hemorrhage and Tolerability of Warfarin in the First Year of Therapy Among Elderly Patients With Atrial Fibrillation
Authors: Hylek Elaine M. , Evans-Molina Carmella , Shea Carol , Henault Lori E. , Regan Susan
Published: May 2007

Background—

Warfarin is effective in the prevention of stroke in atrial fibrillation but is under used in clinical care. Concerns exist that published rates of hemorrhage may not reflect real-world practice. Few patients ≥80 years of age were enrolled in trials, and studies of prevalent use largely reflect a warfarin-tolerant subset. We sought to define the tolerability of warfarin among an elderly inception cohort with atrial fibrillation.

Methods and Results—

Consecutive patients who started warfarin were identified from January 2001 to June 2003 and followed for 1 year. Patients had to be ≥65 years of age, have established care at the study institution, and have their warfarin managed on-site. Outcomes included major hemorrhage, time to termination of warfarin, and reason for discontinuation. Of 472 patients, 32% were ≥80 years of age, and 91% had ≥1 stroke risk factor. The cumulative incidence of major hemorrhage for patients ≥80 years of age was 13.1 per 100 person-years and 4.7 for those <80 years of age (
P
=0.009). The first 90 days of warfarin, age ≥80 years, and international normalized ratio (INR) ≥4.0 were associated with increased risk despite trial-level anticoagulation control. Within the first year, 26% of patients ≥80 years of age stopped taking warfarin. Perceived safety issues accounted for 81% of them. Rates of major hemorrhage and warfarin termination were highest among patients with CHADS
2
scores (an acronym for congestive heart failure, hypertension, age ≥75, diabetes mellitus, and prior stroke or transient ischemic attack) of ≥3.

Conclusions—

Rates of hemorrhage derived from younger noninception cohorts underestimate the bleeding that occurs in practice. This finding coupled with the short-term tolerability of warfarin likely contributes to its underutilization. Stroke prevention among elderly patients with atrial fibrillation remains a challenging and pressing health concern.
B-Type Natriuretic Peptide in Low-Flow, Low-Gradient Aortic Stenosis
Authors: Bergler-Klein Jutta , Mundigler Gerald , Pibarot Philippe , Burwash Ian G. , Dumesnil Jean G. , Blais Claudia , Fuchs Christina , Mohty Dania , Beanlands Rob S. , Hachicha Zeineb , Walter-Publig Nicole , Rader Florian , Baumgartner Helmut
Published: May 2007

Background—

The prognostic value of B-type natriuretic peptide (BNP) is unknown in low-flow, low-gradient aortic stenosis (AS). We sought to evaluate the relationship between AS and rest, stress hemodynamics, and clinical outcome.

Methods and Results—

BNP was measured in 69 patients with low-flow AS (indexed effective orifice area <0.6 cm
2
/m
2
, mean gradient ≤40 mm Hg, left ventricular ejection fraction ≤40%). All patients underwent dobutamine stress echocardiography and were classified as truly severe or pseudosevere AS by their projected effective orifice area at normal flow rate of 250 mL/s (effective orifice area ≤1.0 cm
2
or >1.0 cm
2
). BNP was inversely related to ejection fraction at rest (Spearman correlation coefficient
r
s
=−0.59,
P
<0.0001) and at peak stress (
r
s
=−0.51,
P
<0.0001), effective orifice area at rest (
r
s
=−0.50,
P
<0.0001) and at peak stress (
r
s
=−0.46,
P
=0.0002), and mean transvalvular flow (
r
s
=−0.31,
P
=0.01). BNP was directly related to valvular resistance (
r
s
=0.42,
P
=0.0006) and wall motion score index (
r
s
=0.36,
P
=0.004). BNP was higher in 29 patients with truly severe AS versus 40 with pseudosevere AS (median, 743 pg/mL [Q1, 471; Q3, 1356] versus 394 pg/mL [Q1, 191 to Q3, 906],
P
=0.012). BNP was a strong predictor of outcome. In the total cohort, cumulative 1-year survival of patients with BNP ≥550 pg/mL was only 47±9% versus 97±3% with BNP <550 (
P
<0.0001). In 29 patients who underwent valve replacement, postoperative 1-year survival was also markedly lower in patients with BNP ≥550 pg/mL (53±13% versus 92±7%).

Conclusions—

BNP is significantly higher in truly severe than pseudosevere low-gradient AS and predicts survival of the whole cohort and in patients undergoing valve replacement.
Early Metoprolol Administration Before Coronary Reperfusion Results in Increased Myocardial Salvage
Authors: Ibanez Borja , Prat-González Susanna , Speidl Walter S. , Vilahur Gemma , Pinero Antonio , Cimmino Giovanni , García Mario J. , Fuster Valentin , Sanz Javier , Badimon Juan J.
Published: May 2007

Background—

β-Blockers improve clinical outcome when administered early after acute myocardial infarction. However, whether β-blockers actually reduce the myocardial infarction size is still in dispute. Cardiac magnetic resonance imaging can accurately depict the left ventricular (LV) ischemic myocardium at risk (T2-weighted hyperintense region) early after myocardial infarction, as well as the extent of necrosis (delayed gadolinium enhancement). The aim of this study was to determine whether early administration of metoprolol could increase myocardial salvage, measured as the difference between the extent of myocardium at risk and myocardial necrosis.

Methods and Results—

Twelve Yorkshire pigs underwent a 90-minute left anterior descending coronary occlusion, followed by reperfusion. They were randomized to metoprolol (7.5 mg during myocardial infarction) or placebo. Global and regional LV function, extent of myocardium at risk, and myocardial necrosis were quantified by cardiac magnetic resonance imaging studies performed 4 and 22 days after reperfusion in 10 survivors. Despite similar extent of myocardium at risk in metoprolol- and placebo-treated pigs (30.9% of LV versus 30.6%;
P
=NS), metoprolol resulted in 5-fold-larger salvaged myocardium (32.4% versus 6.2% of myocardium at risk;
P
=0.015). The LV ejection fraction significantly improved in metoprolol-treated pigs between days 4 and 22 (37.2% versus 43.0%;
P
=0.037), whereas it remained unchanged in pigs treated with placebo (35.1% versus 35.0%;
P
=NS). The extent of myocardial salvage was related directly to LV ejection fraction improvement (
P
=0.031) and regional LV wall motion recovery (
P
=0.039) at day 22.

Conclusions—

Early metoprolol administration during acute coronary occlusion increases myocardial salvage. The extent of myocardial salvage, measured as the difference between myocardium at risk and myocardial necrosis, was associated with regional and global LV motion improvement.
Clinical Reminders Attached to Echocardiography Reports of Patients With Reduced Left Ventricular Ejection Fraction Increase Use of β-Blockers
Authors: Heidenreich Paul A. , Gholami Parisa , Sahay Anju , Massie Barry , Goldstein Mary K.
Published: May 2007

Background—

Although β-blockers are known to prolong survival for patients with reduced left ventricular ejection fraction, they are often underused. We hypothesized that a reminder attached to the echocardiography report would increase the use of β-blockers for patients with reduced left ventricular ejection fraction.

Methods and Results—

We randomized 1546 consecutive patients with a left ventricular ejection fraction <45% found on echocardiography at 1 of 3 laboratories to a reminder for use of β-blockers or no reminder. Patients were excluded from analysis if they died within 30 days of randomization (n=89), did not receive medications through the Veterans Affairs system after 30 days (n=180), or underwent echocardiography at >1 laboratory (n=6). The primary outcome was a prescription for an oral β-blocker between 1 and 9 months after randomization. The mean age of the 1271 included patients was 69 years; 60% had a history of heart failure, and 51% were receiving treatment with β-blockers at the time of echocardiography. More patients randomized to the reminder had a subsequent β-blocker prescription (74%, 458 of 621) compared with those randomized to no reminder (66%, 428 of 650;
P
=0.002). The effect of the reminder was not significantly different for subgroups based on patient location (inpatient versus outpatient) or prior use of β-blockers.

Conclusions—

A reminder attached to the echocardiography report increased the use of β-blockers in patients with depressed left ventricular systolic function.
Offsetting Impact of Thrombosis and Restenosis on the Occurrence of Death and Myocardial Infarction After Paclitaxel-Eluting and Bare Metal Stent Implantation
Authors: Stone Gregg W. , Ellis Stephen G. , Colombo Antonio , Dawkins Keith D. , Grube Eberhard , Cutlip Donald E. , Friedman Mark , Baim Donald S. , Koglin Joerg
Published: May 2007

Background—

Drug-eluting stents compared with bare metal stents (BMS) may increase late stent thrombosis (ST), although an accompanying increase in the rates of death and myocardial infarction (MI) has not been observed. We hypothesized that the prevention of restenosis-related adverse events by drug-eluting stents might offset some or all of the excess risk from ST.

Methods and Results—

We analyzed a pooled patient-level database from 4 prospective, double-blind trials in which 3445 patients were randomized to paclitaxel-eluting stents or BMS. The occurrence of death or MI within 7 days of ST or target lesion revascularization was assessed. With a median follow-up of 3.2 years, ST occurred in 34 patients (1.0%), 31 (91.1%) of whom sustained death or MI within 7 days. Target lesion revascularization was performed in 425 patients (12.3%), 15 (3.5%) of whom died or had MI within 7 days. ST occurred in 14 BMS and 20 paclitaxel-eluting stent patients, resulting in 12 and 19 deaths or MIs within 7 days, respectively. Target lesion revascularization was performed in 290 BMS and 135 paclitaxel-eluting stent patients, resulting in 11 and 4 deaths or MI events within 7 days, respectively. In total, 23 patients in both the BMS and paclitaxel-eluting stents groups died or had an MI event within 7 days of either ST or target lesion revascularization.

Conclusions—

ST, although infrequent, results in a high incident rate of death and MI, whereas the more frequent occurrence of target lesion revascularization is associated with a finite but lower rate of death and MI. The marked reduction in restenosis with drug-eluting stents compared with BMS may counterbalance the potential excess risk from late ST with drug-eluting stents.
Relevance of Genetics and Genomics for Prevention and Treatment of Cardiovascular Disease
Authors: Arnett Donna K. , Baird Alison E. , Barkley Ruth A. , Basson Craig T. , Boerwinkle Eric , Ganesh Santhi K. , Herrington David M. , Hong Yuling , Jaquish Cashell , McDermott Deborah A. , O’Donnell Christopher J.
Published: May 2007

Atherosclerotic cardiovascular disease (CVD) is a major health problem in the United States and around the world. Evidence accumulated over decades convincingly demonstrates that family history in a parent or a sibling is associated with atherosclerotic CVD, manifested as coronary heart disease, stroke, and/or peripheral arterial disease. Although there are several mendelian disorders that contribute to CVD, most common forms of CVD are believed to be multifactorial and to result from many genes, each with a relatively small effect working alone or in combination with modifier genes and/or environmental factors. The identification and the characterization of these genes and their modifiers would enhance prediction of CVD risk and improve prevention, treatment, and quality of care. This scientific statement describes the approaches researchers are using to advance understanding of the genetic basis of CVD and details the current state of knowledge regarding the genetics of myocardial infarction, atherosclerotic CVD, hypercholesterolemia, and hypertension. Current areas of interest and investigation—including gene–environment interaction, pharmacogenetics, and genetic counseling—are also discussed. The statement concludes with a list of specific recommendations intended to help incorporate usable knowledge into current clinical and public health practice, foster and guide future research, and prepare both researchers and practitioners for the changes likely to occur as molecular genetics moves from the laboratory to clinic.
Sequential Changes in Antiangiogenic Factors in Early Pregnancy and Risk of Developing Preeclampsia
Authors: Rana Sarosh , Karumanchi S. Ananth , Levine Richard J. , Venkatesha Shivalingappa , Rauh-Hain Jose Alejandro , Tamez Hector , Thadhani Ravi
Published: May 2007

Concentrations of soluble fms-like tyrosine kinase 1 (sFlt1) and soluble endoglin (sEng) increase in maternal blood with the approach of clinical preeclampsia. Although alterations in these circulating antiangiogenic factors herald the signs and symptoms of preeclampsia, in vitro studies suggest they may also play a role in regulating early placental cytotrophoblast functions. Early pregnancy changes in sFlt1 and sEng may thus identify women destined to develop preeclampsia. We performed a nested case-control study of 39 women who developed preeclampsia and 147 contemporaneous normotensive controls each with serum collected in the first (11 to 13 weeks of gestation) and second (17 to 20 weeks) trimesters. Whereas levels of sFlt1 and sEng at 11 to 13 weeks were similar between cases and controls (sFlt1: 3.5±0.3 ng/mL versus 3.0±0.1,
P
=0.14; sEng 6.9±0.3 ng/mL versus 6.6±0.2,
P
=0.37, respectively), at 17 to 20 weeks both were elevated in the women destined to develop preeclampsia (sFlt1: 4.1±0.5 ng/mL versus 3.1±0.1,
P
<0.05; sEng, 6.4±0.4 ng/mL versus 5.2±0.1,
P
<0.01). Women who developed preterm (<37 weeks) preeclampsia demonstrated even greater sequential changes: difference [
delta
{
d}
] between second and first trimester levels:
d
sFlt1, 0.63±0.91 ng/mL in preterm PE versus 0.05±0.15 in controls;
d
sEng, 0.73±0.77 ng/mL versus −1.32±0.18,
P
<0.01. Similar findings were noted in a cross-sectional analysis of specimens collected from the Calcium for Preeclampsia Prevention Study. In conclusion, sequential changes in antiangiogenic factors during early pregnancy may be useful for predicting preterm preeclampsia.
Inhibition of Rac1-Derived Reactive Oxygen Species in Nucleus Tractus Solitarius Decreases Blood Pressure and Heart Rate in Stroke-Prone Spontaneously Hypertensive Rats
Authors: Nozoe Masatsugu , Hirooka Yoshitaka , Koga Yasuaki , Sagara Yoji , Kishi Takuya , Engelhardt John F. , Sunagawa Kenji
Published: May 2007

Reactive oxygen species (ROS) in the brain are thought to contribute to the neuropathogenesis of hypertension by enhancing sympathetic nervous system activity. The nucleus tractus solitarius (NTS), which receives afferent input from baroreceptors, has an important role in cardiovascular regulation. reduced nicotinamide-adenine dinucleotide phosphate oxidase is thought to be a major source of ROS in the NTS. Rac1 is a small G protein and a key component of reduced nicotinamide-adenine dinucleotide phosphate oxidase. The role of Rac1-derived ROS in the NTS in cardiovascular regulation of hypertension is unknown. Therefore, we examined whether inhibition of Rac1 in the NTS decreases ROS generation, thereby reducing blood pressure in stroke-prone spontaneously hypertensive rats (SHRSPs). The basal Rac1 activity level in the NTS was greater in SHRSPs than in Wistar-Kyoto rats. Inhibition of Rac1, induced by transfecting adenovirus vectors encoding dominant-negative Rac1 into the NTS, decreased blood pressure, heart rate, and urinary norepinephrine excretion in SHRSPs but not in Wistar-Kyoto rats. Inhibition of Rac1 also reduced nicotinamide-adenine dinucleotide phosphate oxidase activity and ROS generation. In addition, Cu/Zn-superoxide dismutase activity in the NTS of SHRSPs was decreased compared with that of Wistar-Kyoto rats, despite the increased ROS generation. Overexpression of Cu/Zn-superoxide dismutase in the NTS decreased blood pressure and heart rate in SHRSPs. These results indicate that the activation of Rac1 in the NTS generates ROS via reduced nicotinamide-adenine dinucleotide phosphate oxidase in SHRSPs, and this mechanism might be important for the neuropathogenesis of hypertension in SHRSPs.
Noradrenergic Cell Specific Gene Transfer With Neuronal Nitric Oxide Synthase Reduces Cardiac Sympathetic Neurotransmission in Hypertensive Rats
Authors: Li Dan , Wang Lijun , Lee Chee-Wan , Dawson Tom A. , Paterson David J.
Published: May 2007

Nitric oxide–cGMP pathway can inhibit cardiac norepinephrine (NE) release. Sympathetic hyper-responsiveness in hypertension may result from oxidative stress impairing this pathway. We tested the hypothesis that the gene transfer of neuronal NO synthase (nNOS) could restore sympathetic balance in the spontaneously hypertensive rat (SHR). An adenovirus (5×10
10
particles) constructed with a noradrenergic neuron-specific promoter (PRS ×8) encoding nNOS (Ad.PRS-nNOS) or enhanced green fluorescence protein (Ad.PRS-eGFP) was targeted to the right atrial wall by percutaneous injection in age-matched male SHRs and Wistar-Kyoto (WKY) rats. Five days after transduction, right atria were removed, and evoked [
3
H] norephinephrine (NE) release, NOS activity, and cGMP were measured. In the Ad.PRS-eGFP treated group, tissue levels of cGMP were significantly lower in the SHR compared with the WKY atria. NE release was also greater in the SHR, and soluble guanylate cyclase inhibition did not alter evoked [
3
H] NE release in the Ad.PRS-eGFP–treated SHR. All atria treated with Ad.PRS-nNOS had enhanced nNOS activity when compared with Ad.PRS-eGFP atria. Ad.PRS-nNOS in WKY rats reduced NE release compared with the Ad.PRS-eGFP group. Guanylate cyclase inhibition enhanced NE release in both Ad.PRS-nNOS– and Ad.PRS-eGFP–treated WKY atria. Ad.PRS-nNOS restored cGMP levels in the SHR to those seen in the WKY atria. In the SHR, Ad.PRS-nNOS also attenuated NE release compared with Ad.PRS-eGFP group. This was reversed by guanylate cyclase inhibition. We conclude that artificial upregulation of sympathetic nNOS via gene transfer with a noradrenergic promoter may provide a novel approach for correcting peripheral sympathetic hyperactivity in hypertension.
Flow-Induced Remodeling in Resistance Arteries From Obese Zucker Rats Is Associated With Endothelial Dysfunction
Authors: Bouvet Céline , de Chantemèle Eric Belin , Guihot Anne-Laure , Vessières Emilie , Bocquet Arnaud , Dumont Odile , Jardel Alain , Loufrani Laurent , Moreau Pierre , Henrion Daniel
Published: May 2007

Chronic increases in blood flow increase arterial diameter and NO-dependent dilation in resistance arteries. Because endothelial dysfunction accompanies metabolic syndrome, we hypothesized that flow-mediated remodeling might be impaired in obese rat resistance arteries. Obese and lean Zucker rat mesenteric resistance arteries were exposed to chronic flow increases through arterial ligation in vivo: arteries exposed to high flow were compared with normal flow arteries. Diameter was measured in vitro in cannulated arteries using pressure arteriography. After 7 days, outward remodeling (diameter increased from 346±9 to 412±11 μm at 100 mm Hg) occurred in lean high-flow arteries. Endothelium-dependent tone was reduced in high-flow arteries from obese rats by contrast with lean animals. On the other hand, diameter enlargement occurred similarly in the 2 strains. The involvement of NO in endothelium-dependent dilation (evidenced by NO blockade) and endothelial NO synthase phosphorylation was smaller in obese than in lean rats. Superoxide anion and reduced nicotinamide-adenine dinucleotide phosphate oxidase subunit expression (p67phox and gp91phox) increased in obese rats and were higher in high-flow than in control arteries. Acute Tempol (a catalase mimetic), catalase plus superoxide dismutase, and
l
-arginine plus tetrahydrobiopterin restored endothelium-dependent dilation in obese rat normal and high-flow arteries to the level found in lean control arteries. Thus, flow-induced remodeling in obese resistance arteries was associated with a reduced endothelium-mediated dilation because of a decreased NO bioavailability and an excessive superoxide production. This dysfunction might have negative consequences in ischemic diseases in patients with obesity or metabolic syndrome.
Role of Matrix Metalloproteinases in Early Hypertensive Vascular Remodeling
Authors: Flamant Martin , Placier Sandrine , Dubroca Caroline , Esposito Bruno , Lopes Izolina , Chatziantoniou Christos , Tedgui Alain , Dussaule Jean-Claude , Lehoux Stéphanie
Published: May 2007

Hypertension is associated with vascular remodeling characterized by rearrangement of extracellular matrix proteins. To evaluate how matrix metalloproteinase (MMP)-9 contributes to the progression of hypertensive vascular disease in vivo, wild-type (wt) or MMP-9
−/−
mice were treated with angiotensin II (Ang II; 1 μg/kg per minute, by minipump) plus a 5% NaCl diet during 10 days. Baseline blood pressure was equivalent in wt and knockout mice, but Ang II treatment increased systolic blood pressure to a greater extent (
P
<0.05) in MMP-9
−/−
mice (94±6 to 134±6 mm Hg;
P
<0.001) than in wt animals (93±4 to 114±6 mm Hg;
P
<0.01). In wt mice, Ang II treatment increased the carotid artery pressure-diameter relationship significantly, and maximal diameter reached 981±19 μm (
P
<0.01 versus sham; 891±10 μm). In contrast, in MMP-9
−/−
mice, carotid artery compliance was actually reduced after Ang II (
P
<0.05), and maximal diameter only reached 878±13 μm. Ang II treatment induced MMP-2 and increased carotid media thickness equally in both phenotypes. However, MMP-9 induction and in situ gelatinase activity were only enhanced in Ang II-treated wt mice, and vessels from these mice also produced more collagen I breakdown products than their MMP-9
−/−
counterparts (
P
<0.05). Inversely, staining for collagen IV was particularly enhanced in vessels from MMP-9
−/−
mice treated with Ang II. These results demonstrate the following: (1) the onset of Ang II-induced hypertension is accompanied by increased MMP-9 activity in conductance vessels; (2) absence of MMP-9 activity results in vessel stiffness and increased pulse pressure; and (3) MMP-9 activation is associated with a beneficial role early on in hypertension by preserving vessel compliance and alleviating blood pressure increase.
Diastolic Blood Pressure and Mortality in the Elderly With Cardiovascular Disease
Authors: Protogerou Athanase D. , Safar Michel E. , Iaria Pierre , Safar Hélène , Le Dudal Katia , Filipovsky Jan , Henry Olivier , Ducimetière Pierre , Blacher Jacques
Published: May 2007

Isolated systolic hypertension is predominantly observed in the elderly because of increased arterial stiffness. Aggressive treatment leads to excessive lowering of diastolic blood pressure and favors the presence of a J-shaped curve association with mortality. We investigated whether, in the elderly, this pattern of association is a simple epiphenomenon of increased arterial stiffness and impaired cardiac function. In a cohort of 331 hospitalized subjects >70 years old (mean age±SD: 85±7 years), aortic pulse wave velocity and pressure wave reflections, by pulse wave analysis, and cardiac function, by ultrasound, were assessed. During a 2-year follow-up period, 110 subjects died. No association of prognosis with systolic pressure, pulse pressure, or pulse wave velocity was observed. A J-shaped association between diastolic pressure and overall and cardiovascular mortality was observed. Unadjusted Cox regression analysis showed that patients in the first tertile of diastolic pressure (≤60 mm Hg) had higher mortality. In Cox regression analysis, diastolic pressure ≤60 mm Hg was a predictor of mortality independently from cardiac–vascular properties, cardiovascular risk factors, and drug treatment. Multivariate regression analysis showed that increased age and low total peripheral resistance, but not left ventricular function, were the cardinal determinants of low diastolic pressure. An “optimal” diastolic pressure of 70 mm Hg in subjects with isolated systolic hypertension was found. We showed that, in the frail elderly, a value of diastolic blood pressure ≤60 mm Hg is associated with reduced survival, independent from large artery stiffness and left ventricular function, suggesting that more rational antihypertensive therapy, not only based on systolic pressure level, is needed.
Plasma testosterone levels of male European starlings (Sturnus vulgaris) during the breeding cycle and in relation to song and paternal care
Authors: Eens Marcel , Darras Veerle , Arckens Lutgarde , de Ridder Elke , Pinxten Rianne
Published: May 2007

In temperate-zone birds, seasonal testosterone (T) profiles often vary among species with different mating systems. The trade-off hypothesis suggests that T levels in male birds represent a trade-off between additional mating effort, stimulated by high T, and paternal effort, inhibited by high T. To study the role of T in mediating the trade-off between paternal and mating effort in the facultatively polygynous European starling (

Sturnus vulgaris

), we monitored seasonal fluctuations in T levels and song activity, which functions mainly in mate attraction, and we investigated natural covariation between plasma T levels and male parental and song behaviour during the parental phase. T concentrations peaked during nest building, remained high during the fertile period, and then decreased gradually during the period of paternal care. This resembles the profile typically found in polygynous species with biparental care. Seasonal variation in song activity paralleled seasonal changes in T. The proportion of time spent incubating was significantly negatively correlated with T levels in individual males. There was a positive, but non-significant, correlation between song activity at an additional nest box and T levels during incubation. We suggest that this negative correlation between T and incubation behaviour may be partly explained by T increases in males responding to the presence of prospecting females with additional nestbox occupation and mate attraction song, rather than that high T levels stimulate mate attraction song. During the feeding period, characterized by a very low availability of unmated females, variation in T levels was low and there was no covariation between T and feeding. T levels during the parental phase reflect, but do not seem to directly regulate, the trade-off between parental and additional mating effort and other factors such as opportunities for additional matings may influence the resolution of this reproductive trade-off.
Female choice in the penduline tit Remiz pendulinus: the effects of nest size and male mask size
Authors: Pogány Ákos , Székely Tamás
Published: May 2007

Why do females prefer some males over others? Females often use multiple cues, and to distinguish between these cues one needs to manipulate putative male traits. We carried out a test of multiple cues hypothesis in a polygamous bird, the penduline tit

Remiz pendulinus

. In this passerine both males and females mate with up to six mates within a breeding season, and a single parent (male or female) incubates the eggs and raises the chicks. Males build sophisticated nests, and previous studies suggested that females prefer males with large nest to small ones, since large nests provide direct benefit to females

via

reduced cost of incubation. Males sport wider eye-stripes ('masks') than females, and males with large masks find a mate faster than males with small masks. In a mate choice experiment using factorial design and two levels for each trait, we show that females prefer males with large masks, whereas they do not show preference for large nests. These results suggest that in penduline tits (i) females pay more attention to a trait that signals indirect benefit (mask size) than a trait that is related to direct benefits (nest size), and (ii) nest preference may be context-dependent.
Is UV signalling involved in male-male territorial conflict in the blue tit (Cyanistes caeruleus)? A new experimental approach
Authors: Dijkstra Thomas , Korsten Peter , Komdeur Jan
Published: May 2007

Structurally-based ultraviolet (UV) coloration of plumage can signal male quality and plays a role in female mate choice in many bird species. UV-reflecting badges could also be important signals in male-male competition. We tested if territorial blue tit (

Cyanistes caeruleus

) males discriminate between conspecific male intruders which differ in the UV reflectance of their crown feathers. To this aim, we used a new experimental approach in which we simultaneously (instead of sequentially) introduced two male blue tit taxidermic mounts in the territories of resident males during the female fertile period; one mount with natural crown UV reflectance and one mount with reduced crown UV. The two mounts provoked strong aggressive reactions from resident males. Males specifically directed their aggression to conspecific intruders, as a male blue tit mount received substantially more aggression than a mount of a European robin (

Erithacus rubecula

). However, aggression of resident males did not vary between the UV-reduced and the control mount. Furthermore, the variation in natural crown UV reflectance of the resident males did not predict the intensity of their aggressive response. Contrary to previous findings our results suggest that UV signals play only a limited role in male-male interactions during territorial intrusions in the female fertile period.
Is broodmate aggression really associated with direct feeding?
Authors: Gonzalez-Voyer Alejandro , Drummond Hugh
Published: May 2007

The Feeding Method hypothesis (FMH) proposes that the way parents transfer food to chicks influences whether broodmates compete for it aggressively or non-aggressively. The FMH assumes that aggression is more efficient for securing a large share of food when prey items pass from bill to bill (direct feeds) than when prey is deposited on the nest floor (indirect feeds). In species with a developmental transition from indirect to direct feeding, the hypothesis predicts more aggression during direct than indirect feeds and an increase in rates of aggression as feeding becomes increasingly direct. We quantified development of aggression and feeding in two-chick cattle egret (

Bubulcus ibis

) broods in order to test the FMH's assumption and its two developmental predictions. We also examined whether changes in rates of aggression early in the nestling period are better predicted by the Feeding Method, Food Amount or Early Dominance Establishment hypotheses. Neither the assumption nor either of the predictions of the FMH was supported and, if anything, senior broodmates were more aggressive early in the nestling period when feeding was indirect. These observations cast doubt on the ultimate influence of feeding method on use of aggression and, especially, on the role of direct feeding as a proximate trigger for aggression. Rates of aggression better fitted the temporal patterns predicted by Early Dominance Establishment and Food Amount hypotheses.
Estimation of Seasonal Precipitation Tercile-Based Categorical Probabilities from Ensembles
Authors: Tippett Michael K. , Barnston Anthony G. , Robertson Andrew W.
Published: May 2007

Ensemble simulations and forecasts provide probabilistic information about the inherently uncertain climate system. Counting the number of ensemble members in a category is a simple nonparametric method of using an ensemble to assign categorical probabilities. Parametric methods of assigning quantile-based categorical probabilities include distribution fitting and generalized linear regression. Here the accuracy of counting and parametric estimates of tercile category probabilities is compared. The methods are first compared in an idealized setting where analytical results show how ensemble size and level of predictability control the accuracy of both methods. The authors also show how categorical probability estimate errors degrade the rank probability skill score. The analytical results provide a good description of the behavior of the methods applied to seasonal precipitation from a 53-yr, 79-member ensemble of general circulation model simulations. Parametric estimates of seasonal precipitation tercile category probabilities are generally more accurate than the counting estimate. In addition to determining the relative accuracies of the different methods, the analysis quantifies the relative importance of the ensemble mean and variance in determining tercile probabilities. Ensemble variance is shown to be a weak factor in determining seasonal precipitation probabilities, meaning that differences between the tercile probabilities and the equal-odds probabilities are due mainly to shifts of the forecast mean away from its climatological value.
Cultural Tourism Product: Pacific Island Migrant Perspectives in New Zealand
Authors: Cave Jenny , Ryan Chris , Panakera Charlie
Published: May 2007

The development of tourism cultural product in the case of minority peoples has become a mechanism for affirming traditional values, a restatement of identity, and an assertion of political and social aspirations. This is true for Pacific Island communities in Auckland, New Zealand, that are economically, socially, and politically marginalized. These peoples account for approximately 14% of Auckland's population, have retained several traditional features and connections with home islands through extended family networks, and have been well established in the city for over 60 years. The article reports research findings based on a mixed method of participation in discussions and political processes and results derived from a questionnaire. The study reveals differences between migrant and host communities toward the perceived attractiveness of the proposed tourism development and also indicates issues relating to management and product placement summarized in a model based on dimensions of cultural content and modes of management.
Destination Image and Its Functional Relationships
Authors: Tasci Asli D.A. , Gartner William C.
Published: May 2007

Destination image is commonly accepted as an important aspect in successful tourism development and destination marketing due to its impact on both supply- and demand-side aspects of marketing. Despite the ample amount of literature, a comprehensive conceptualization of destination image comprising its intricate relationships with several other factors on the supply and demand sides of the market has yet to emerge. In this study, a large body of literature on destination image and related concepts is reviewed and a comprehensive conceptualization of destination image is modeled. It was concluded that there are still many facets of this complex construct yet to be investigated empirically.
Stated Economic and Social Motivations of Farm Tourism Operators
Authors: Ollenburg Claudia , Buckley Ralf
Published: May 2007

Farm tourism enterprises combine the commercial constraints of regional tourism, the nonfinancial features of family businesses, and the inheritance issues of family farms. They have theoretical significance in regional tourism geography and economics, family tourism business dynamics, and rural diversification. We examined motivations of farm tourism operators throughout Australia using both qualitative and quantitative methods. In contrast to Europe and the United States, social motivations are marginally more important overall than economic motivations. For most operators, however, both are important; and different motivations are dominant for different types of farm landholders and at different stages in farm, family, and business lifecycles. For some families, tourism is a critical component of income streams to keep the current generation on the family property and provide opportunities for succeeding generations. For others it combines social opportunities with retirement income. Tourism, agricultural, or rural initiatives, including farm tourism, need to incorporate this diversity.
Perceptions-Based Analysis of Tourism Products and Service Providers
Authors: Mazanec Josef A. , Strasser Helmut
Published: May 2007

Perceptions-based analysis is a general framework for analyzing tourist choice alternatives involving large sets of perceived attributes. Its development in tourism research was encouraged as tourism is characterized by multifaceted choice alternatives such as destinations and other experiential “products” that the tourists cannot succinctly evaluate with a small number of attributes. PBA differentiates between the generic perceptions of a class of choice alternatives (destinations, product/service providers; e.g., “metropolitan city”; “tour operator”), the perceptual profiles of a specific choice alternative (“San Francisco”; “Thomas Cook”), and the profiles of the choice alternatives preferred or actually selected. It condenses the attribute profiles into distinguished perceptual positions and analyzes their competitive relationships by diagnosing the perceptual strengths and weaknesses of the choice alternatives. Further analysis reveals the number of choice decisions made in favor of a uniquely positioned choice alternative or one sharing its position with others. An empirical example for tour operators illustrates the various data processing steps and discusses their policy implications.
Relationship Marketing and Information and Communication Technologies: Analysis of Retail Travel Agencies
Authors: Suárez Álvarez Leticia , Díaz Martín Ana María , Casielles Rodolfo Vázquez
Published: May 2007

The development of information and communication technologies (ICTs) has had profound effects in goods and services marketing. In particular, the advent of electronic commerce has forced companies to face new types of competition and customer relationship management to survive in markets. This study analyzes the Internet's effect as a new distribution channel on traditional retail travel agencies and evaluates the opportunities it offers them, dispelling the idea that it is a threat. The effect of ICTs on customers' trust is also examined, and the results open ways to improve the management of business relationships with customers.
The Health Status of Retired American Football Players
Authors: Nicholas Stephen J. , Nicholas James A. , Nicholas Calvin , Diecchio Jennifer R. , McHugh Malachy P.
Published: May 2007

Background

Despite a perception that retired professional football players have poor health, there are little supporting data.

Hypothesis

Retired football players have poor health compared with age-matched population norms.

Study Design

Cross-sectional study; Level of evidence, 4.

Methods

Thirty-six of 41 members of the 1969 Super Bowl winning team were contacted 35 years after that event (3 were deceased, and no contact information was available for 2). Players completed an SF-36 health survey and a medical history and football-specific questionnaire. Each player's football-related injury history before 1969 was documented from medical records. It was estimated that there was 80% power to detect a 10% difference in physical and mental health scores between the retired football players (age, 62 ± 3 y) and population norms (n = 741) at an alpha level of 0.05.

Results

SF-36 scores for physical and mental health were not different from age-matched norms (physical health P = .69; mental health P = .49). The most prevalent medical conditions were arthritis (24 of 36 players), hypertension (13 of 36 players), and chronic low back pain (13 of 36 players). SF-36 physical health scores were 21% lower in players with arthritis (P < .01) and back pain (P < .05) compared with the other players. Physical health scores were 19% above normal for players without arthritis (P < .01) and not different from normal for players with arthritis (6% lower; P = .6). Four of 8 players who had major ligamentous injuries to the knee before 1969 had total knee arthroplasty in the intervening years, compared with 3 of the remaining 28 players (P < .05). The men played professional football for 8.3 ± 3.8 years, and 33 players (94%) reported having had “very fulfilling” (n = 24) or “somewhat fulfilling” (n = 9) careers.

Conclusion

These professional football players had long and fulfilling careers with no apparent long-term detrimental effects on physical or mental health scores despite a high prevalence of arthritis.