bluuebunny/crossref_metadata_2025 huggingface dataset:
Carotid Arterial Stiffness and Its Relationship to Exercise Intolerance in Older Patients With Heart Failure and Preserved Ejection Fraction
Authors: Kitzman Dalane W. , Herrington David M. , Brubaker Peter H. , Moore J. Brian , Eggebeen Joel , Haykowsky Mark J.
Published: November 2012

Heart failure with a preserved ejection fraction (HFpEF) is the dominant form of heart failure in the older population. The primary chronic symptom in HFpEF is severe exercise intolerance; however, its pathophysiology and therapy are not well understood. We tested the hypothesis that older patients with HFpEF have increased arterial stiffness beyond what occurs with normal aging and that this contributes to their severe exercise intolerance. Sixty-nine patients ≥60 years of age with HFpEF and 62 healthy volunteers (24 young healthy subjects ≤30 years and 38 older healthy subjects ≥60 years old) were examined. Carotid arterial stiffness was assessed using high-resolution ultrasound, and peak exercise oxygen consumption was measured using expired gas analysis. Peak exercise oxygen consumption was severely reduced in the HFpEF patients compared with older healthy subjects (14.1±2.9 versus 19.7±3.7 mL/kg per minute;
P
<0.001) and in both was reduced compared with young healthy subjects (32.0±7.2 mL/kg per minute; both
P
<0.001). In HFpEF compared with older healthy subjects, carotid arterial distensibility was reduced (0.97±0.45 versus 1.33±0.55×10
–3
mm Hg
−1
;
P
=0.008) and Young’s elastic modulus was increased (1320±884 versus 925±530 kPa;
P
<0.02). Carotid arterial distensibility was directly (0.28;
P
=0.02) and Young’s elastic modulus was inversely (–0.32;
P
=0.01) related to peak exercise oxygen consumption. Carotid arterial distensibility is decreased in HFpEF beyond the changes attributed to normal aging and is related to peak exercise oxygen consumption. This supports the hypothesis that increased arterial stiffness contributes to exercise intolerance in HFpEF and is a potential therapeutic target.
Renal Sympathetic Denervation Provides Ventricular Rate Control But Does Not Prevent Atrial Electrical Remodeling During Atrial Fibrillation
Authors: Linz Dominik , Mahfoud Felix , Schotten Ulrich , Ukena Christian , Hohl Mathias , Neuberger Hans-Ruprecht , Wirth Klaus , Böhm Michael
Published: November 2012

Renal denervation (RDN) reduces renal efferent and afferent sympathetic activity thereby lowering blood pressure in resistant hypertension. The effect of modulation of the autonomic nervous system by RDN on atrial electrophysiology and ventricular rate control during atrial fibrillation (AF) is unknown. Here we report a reduction of ventricular heart rate in a patient with permanent AF undergoing RDN. Subsequently, we investigated the effect of RDN on AF-induced shortening of atrial effective refractory period, AF inducibility, and ventricular rate control during AF maintained by rapid atrial pacing in 12 pigs undergoing RDN (n=7) or sham procedure (n=5). During sinus rhythm, RDN reduced heart rate (RR-interval, 708±12 versus 577±19 ms;
P
=0.0021) and increased atrioventricular node conduction time (PQ-interval, 112±12 versus 88±9 ms;
P
=0.0001). Atrial tachypacing for 30 minutes increased AF inducibility and decreased AF cycle length. This was not influenced by RDN. RDN reduced ventricular rate during AF episodes by ≈24% (119±9 versus 158±19 bpm;
P
=0.0001). AF episodes were shorter after RDN compared with sham (12±3 versus 34±4 s;
P
=0.0091), but atrial effective refractory period was not modified by RDN. RDN reduced heart rate and reduced atrioventricular node conduction time during sinus rhythm and provided rate control during AF. AF-induced atrial electrical remodeling, AF inducibility, and AF cycle length were not modified, but duration of AF episodes was shorter after RDN. Modulation of the autonomic nervous system by RDN might provide rate control and reduce susceptibility to AF. Whether RDN may provide rate control in a larger number of patients with AF deserves further clinical studies.
Thromboxane Receptors in Smooth Muscle Promote Hypertension, Vascular Remodeling, and Sudden Death
Authors: Sparks Matthew A. , Makhanova Natalia A. , Griffiths Robert C. , Snouwaert John N. , Koller Beverly H. , Coffman Thomas M.
Published: November 2012

The prostanoid thromboxane A2 has been implicated to contribute to the pathogenesis of many cardiovascular diseases, including hypertension. To study the role of vascular thromboxane-prostanoid (TP) receptors in blood pressure regulation, we generated mice with cell-specific deletion of TP receptors in smooth muscle using
Cre/Loxp
technology. We crossed the KI
SM22α-Cre
transgenic mouse line expressing
Cre
recombinase in smooth muscle cells with a mouse line bearing a conditional allele of the
Tbxa2r
gene (
Tp

flox

). In KI
SM22α-Cre
+
Tp

flox/flox

(TP-SMKO) mice, TP receptors were efficiently deleted from vascular smooth muscle cells. In TP-SMKOs, acute vasoconstrictor responses to the TP agonist U46619 were attenuated to a similar extent in both the peripheral and renal circulations. Yet, acute vascular responses to angiotensin II were unaffected at baseline and after chronic angiotensin II administration. Infusion of high-dose U46619 caused circulatory collapse and death in a majority of control mice but had negligible hemodynamic effects in TP-SMKOs, which were completely protected from U46619-induced sudden death. Baseline blood pressures were normal in TP-SMKOs. However, the absence of TP receptors in vascular smooth muscle cells was associated with significant attenuation of angiotensin II–induced hypertension and diminished vascular remodeling. This was also associated with reduced urinary thromboxane production after chronic angiotensin II. Thus, TP receptors in vascular smooth muscle cells play a major role in mediating the actions of thromboxane A
2
in TP agonist-induced shock, hypertension, and vascular remodeling of the aorta.
Addition of Highly Sensitive Troponin T and N-Terminal Pro-B-Type Natriuretic Peptide to Electrocardiography for Detection of Left Ventricular Hypertrophy
Authors: Martinez-Rumayor Abelardo A. , de Lemos James A. , Rohatgi Anand K. , Ayers Colby R. , Powell-Wiley Tiffany M. , Lakoski Susan G. , Berry Jarett D. , Khera Amit , Das Sandeep R.
Published: November 2012

Left ventricular hypertrophy (LVH) is an independent, modifiable risk factor for cardiovascular disease. However, current screening strategies are limited. In 2478 participants without clinical disease from the Dallas Heart Study, we evaluated a multimarker screening strategy that complements electrocardiographic (ECG) criteria for LVH with 2 biomarkers, amino-terminal pro-B-type natriuretic peptide and highly sensitive cardiac troponin T. An integer LVH risk score from 0 to 3 was determined as the sum of the following: (1) LVH by Sokolow-Lyon ECG; (2) amino-terminal pro-B-type natriuretic peptide in the highest sex-specific quartile; and (3) detectable cardiac troponin T. Cardiac magnetic resonance imaging–determined LVH served as the primary outcome. The probability of LVH increased from 2% with an LVH risk score of 0 to 50% with a score of 3 (
P
<0.001). Sokolow-Lyon ECG afforded low sensitivity (26% [95% confidence interval {CI}, 17–32%]) and high specificity (96% [95% CI, 95–97%]), whereas a risk score ≥2 offered higher sensitivity (44% [95% CI, 34–51%]) with good specificity (90% [95% CI, 89–93%]) and a score threshold of 1 offered reasonable sensitivity (76% [95% CI, 67–83%]) with lower specificity (55% [95% CI, 53–61%]) and high negative predictive value (98% [95% CI, 97–98%]). Area under the receiver operator characteristic curve improved from 0.760 (95% CI, 0.716–0.804) for ECG alone to 0.798 (95% CI, 0.754–0.842) for the LVH risk score (
P
=0.0012), consistent with modest improvement in overall discrimination. Better screening for LVH may be achieved by combining simple tests, which collectively provide additional information compared with ECG alone. Further studies are needed to evaluate the impact and cost-effectiveness of a multimarker screening strategy.
Effect of SR Manipulation on Conduit Artery Dilation in Humans
Authors: Carter Howard H. , Dawson Ellen A. , Birk Gurpreet K. , Spence Angela L. , Naylor Louise H. , Cable N. Timothy , Thijssen Dick H.J. , Green Daniel J.
Published: November 2012

The impact of manipulating shear stress on conduit artery vasodilation has not been comprehensively described in vivo. We hypothesized that manipulation of SR through the brachial and radial arteries would be associated with corresponding changes in diameter. We performed a series of studies involving the following: (1) leg cycle exercise at increasing intensities (≈70 and 85% maximum heart rate [HRmax]) with simultaneous bilateral measurement of SR in the radial arteries; (2) leg cycle exercise for 30 minutes at 80% HRmax with simultaneous bilateral measurement of velocity and diameter in the brachial arteries; and (3) bilateral forearm heating for 30 minutes with simultaneous bilateral measurement of brachial artery diameter and blood velocity. Cycling and forearm heating interventions were performed in the presence of unilateral cuff inflation throughout the experiment, or starting during the intervention (15 minutes), to manipulate SR responses. Cuff placement was associated with lower radial artery SR responses (cuffed versus uncuffed, 248±49 versus 349±105 L/s 85% HRmax;
P
<0.01), and diameter responses were similarly attenuated (2.45±0.30 versus 2.78±0.20 mm 85% HRmax;
P
<0.05). Exercise performed at 80% HRmax in the presence of unilateral cuff inflation also reduced brachial artery SR (cuffed versus uncuffed; 258±107 versus 454±157 L/s;
P
<0.01) and diameter (3.96±0.39 versus 4.20±0.45 mm). Finally, cuff inflation decreased the impact of forearm heating on brachial SR (cuffed versus uncuffed; 262±97 versus 440±106 L/s;
P
<0.01) and diameter (4.35±0.54 versus 4.87±0.47 mm;
P
<0.05). Similar significant differences between the cuffed and uncuffed limbs in SR and diameter were observed when cuff inflation occurred during exercise or heating. Our findings strongly implicate SR as an important stimulus to increase conduit artery diameter in humans.
Prenatal Programming of Hypertension Induces Sympathetic Overactivity in Response to Physical Stress
Authors: Mizuno Masaki , Siddique Khurrum , Baum Michel , Smith Scott A.
Published: November 2012

Small-for-gestational-age infants are known to develop hypertension in adulthood. This prenatal programming of hypertension (PPH) can result from several insults including maternal dietary protein deprivation, uteroplacental insufficiency, and prenatal administration of glucocorticoids. The mechanisms underlying the development of hypertension remain unclear although the sympathetic nervous system has been indirectly implicated. This study was designed to directly measure renal sympathetic nerve activity both at rest and during physical stress in an animal model of PPH. The adult male offspring of rats fed either a 6% (PPH) or 20% protein diet (control) were investigated. Conscious systolic blood pressure measured by tail cuff was significantly higher in PPH compared with control (140 ± 3 versus 128 ± 3 mm Hg;
P
<0.05). Baseline mean arterial pressure, heart rate, and renal sympathetic activity were not different between groups during isoflurane anesthesia or after decerebration. Physical stress was induced in decerebrate animals by activating the exercise pressor reflex during static muscle contraction. Stimulation of the exercise pressor reflex evoked significantly larger changes from baseline in mean arterial pressure (40 ± 7 versus 20 ± 4 mm Hg;
P
<0.05), heart rate (19 ± 3 versus 5 ± 1 bpm;
P
<0.05), and renal sympathetic activity (198 ± 29% versus 68 ± 14%;
P
<0.05) in PPH as compared with control. The data demonstrate that the sympathetic response to physical stress is markedly exaggerated in PPH and may play a significant role in the development of hypertension in adults born small for gestational age.
Common Polymorphisms in the
CYP11B1
and
CYP11B2
Genes: Evidence for a Digenic Influence on Hypertension
Authors: Alvarez-Madrazo Samantha , MacKenzie Scott M. , Davies Eleanor , Fraser Robert , Lee Wai-Kwong , Brown Morris , Caulfield Mark J. , Dominiczak Anna F. , Farrall Martin , Lathrop Mark , Hedner Thomas , Melander Olle , Munroe Patricia B. , Samani Nilesh , Stewart Paul M. , Wahlstrand Björn , Webster John , Palmer Colin N.A. , Padmanabhan Sandosh , Connell John M.
Published: November 2012

The locus encompassing the corticosteroidogenic genes
CYP11B2
and
CYP11B1
is of potential importance in essential hypertension. We analyzed the association of polymorphisms at this locus with risk of essential hypertension, using 2 white case–control collections for discovery (n=3340) and confirmation (n=2929). Single-marker and haplotype analyses were performed, with the
CYP11B2
Intron 2 Conversion polymorphism showing strongest association with hypertension in both cohorts and in combined analysis (odds ratio=1.16,
P
=8.54×10
−5
). The
CYP11B1
ACA haplotype associated with increased risk of hypertension relative to the alternative, GTC (odds ratio=1.11;
P
=7.4×10
−3
), whereas the
CYP11B2
TWtC haplotype seemed protective relative to the contrasting CConvT (odds ratio=0.88,
P
=2.2×10
−3
). Analysis spanning the whole
CYP11B1/CYP11B2
locus showed that haplotypes associated with raised risk of hypertension tend to coexist. Functional analysis of heterozygous human adrenal tissue demonstrated decreased
CYP11B2
expression and increased
CYP11B1
expression for those alleles associating with reduced risk of hypertension. These results confirm the hypertensive influence of this locus, with data suggesting a complex digenic mechanism whereby altered relative
CYP11B1
and
CYP11B2
gene expression could have a chronic effect on enzyme activity and corticosteroid synthesis.
Endothelial NO Synthase Augments Fetoplacental Blood Flow, Placental Vascularization, and Fetal Growth in Mice
Authors: Kulandavelu Shathiyah , Whiteley Kathie J. , Bainbridge Shannon A. , Qu Dawei , Adamson S. Lee
Published: November 2012

It is not known whether eNOS deficiency in the mother or the conceptus (ie, placenta and fetus) causes fetal growth restriction in mice lacking the endothelial NO synthase gene (eNOS knockout [KO]). We hypothesized that eNOS sustains fetal growth by maintaining low fetoplacental vascular tone and promoting fetoplacental vascularity and that this is a conceptus effect and is independent of maternal genotype. We found that eNOS deficiency blunted fetal growth, and blunted the normal increase in umbilical blood flow and umbilical venous diameter and the decrease in umbilical arterial Resistance Index in late gestation (14.5–17.5 days) in eNOS KO relative to C57Bl/6J controls. On day 17.5, fetoplacental capillary lobule length and capillary density in vascular corrosion casts were reduced in eNOS KO placentas. Reduced vascularization may be a result of decreased vascular endothelial growth factor mRNA and protein expression in eNOS KO placentas at this stage. These factors, combined with significant anemia found in eNOS KO fetuses, would be anticipated to reduce fetal oxygen delivery and contribute to the fetal tissue hypoxia that was detected in the heart, lung, kidney, and liver by immunohistochemistry using pimonidazole. Although maternal eNOS deficiency impairs uteroplacental adaptations to pregnancy, maternal genotype was not a significant factor affecting growth in heterozygous conceptuses. This indicates that fetal growth restriction was primarily caused by conceptus eNOS deficiency. In mice, placental hemodynamic and vascular changes with gestation and growth restriction showed strong parallels with human pregnancy. Thus, the eNOS KO model could provide insights into the pathogenesis of human intrauterine growth restriction.
Higher Ambulatory Blood Pressure Is Associated With Aortic Valve Calcification in the Elderly
Authors: Iwata Shinichi , Russo Cesare , Jin Zhezhen , Schwartz Joseph E. , Homma Shunichi , Elkind Mitchell S.V. , Rundek Tatjana , Sacco Ralph L. , Di Tullio Marco R.
Published: November 2012

Aortic valve calcification (AVC) without outflow obstruction (stenosis) is common in the elderly and increases the risk of cardiovascular morbidity and mortality. Although high blood pressure (BP) measured at the doctor’s office is known to be associated with AVC, little is known about the association between 24-hour ambulatory BP (ABP) and AVC. Our objective was to clarify the association between ABP variables and AVC. The study population consisted of 737 patients (mean age, 71±9 years) participating in the Cardiovascular Abnormalities and Brain Lesions study who underwent 24-hour ABP monitoring. Each aortic valve leaflet was graded on a scale of 0 (normal) to 3 (severe calcification). A total valve score (values 0–9) was calculated as the sum of all leaflet scores. Advanced AVC (score ≥4) was present in 77 subjects (10.4%). All of the systolic ABP variables (except systolic BP nocturnal decline) and mean asleep diastolic BP were positively associated with advanced calcification, whereas normal dipping status and diastolic BP nocturnal decline were negatively associated. Multiple regression analysis indicated that mean awake diastolic BP (odds ratio, 1.31 [95% CI, 1.01–1.71]) and asleep diastolic BP (odds ratio, 1.34 [95% CI, 1.04–1.72]) remained independently associated with advanced calcification after adjustment for age, sex, cigarette smoking, diabetes mellitus, hypercholesterolemia, hypertension, serum creatinine, and any degree of aortic insufficiency. Diastolic ABP is independently associated with advanced calcification. This finding may have important implications in gaining further insight into the mechanism of AVC.
Soluble Urokinase Plasminogen Activator Receptor is Associated With Inflammation in the Vulnerable Human Atherosclerotic Plaque
Authors: Edsfeldt Andreas , Nitulescu Mihaela , Grufman Helena , Grönberg Caitriona , Persson Ana , Nilsson Marie , Persson Margaretha , Björkbacka Harry , Gonçalves Isabel
Published: November 2012

Background and Purpose—

Recently, plasma soluble urokinase plasminogen activator receptor (suPAR) has gained interest as a marker of cardiovascular risk. suPAR is released through the cleavage of urokinase plasminogen activator receptor (uPAR), which is found in monocytes, activated T-lymphocytes and endothelial cells, all involved in atherosclerosis. suPAR levels have been well studied in plasma, but no studies have focused on suPAR in human atherosclerotic plaques. The aim of this study was to determine whether suPAR measured in the plaque is associated with symptomatic plaques and plaque inflammation.

Methods—

Plasma and carotid plaques from 162 patients were analyzed. Lipids, collagen, uPAR, and macrophages were measured histologically. Cytokines and suPAR were measured in homogenized plaque extracts using multiplex immunoassay and ELISA, respectively. Plasma levels of suPAR were analysed with ELISA. CD3, CD4, as well as uPAR mRNA expression were assessed with quantitative real-time polymerase chain reaction in plaque homogenates from 123 patients.

Results—

Plaque and plasma suPAR levels were higher in symptomatic patients compared with asymptomatic patients. Plaque suPAR levels correlated with plaque content of lipids and macrophages and with proinflammatory chemokines and cytokines monocyte chemoattractant protein 1, tumor necrosis factor α, interleukin 1β, interleukin 6, platelet-derived growth factor AB/BB, monocyte inflammatory protein 1β, regulated on activation normal T-cell expressed and secreted, and s-CD40L. uPAR mRNA and histological staining for uPAR correlated with plaque content of suPAR.

Conclusion—

This study shows that suPAR in human carotid plaques and plasma is associated with the presence of symptoms and that plaque suPAR is associated with the vulnerable inflammatory plaque. These findings strengthen the hypothesis of suPAR as a future marker of vulnerable atherosclerotic plaques.
Impairment of Cerebral Autoregulation Predicts Delayed Cerebral Ischemia After Subarachnoid Hemorrhage
Authors: Budohoski Karol P. , Czosnyka Marek , Smielewski Peter , Kasprowicz Magdalena , Helmy Adel , Bulters Diederik , Pickard John D. , Kirkpatrick Peter J.
Published: November 2012

Background and Purpose—

Delayed cerebral ischemia (DCI) is a recognized contributor to unfavorable outcome after subarachnoid hemorrhage (SAH). Recent data challenge the concept of vasospasm as the sole cause of ischemia and suggest a multifactorial process with dysfunctional cerebral autoregulation as a component. We tested the hypothesis that early autoregulatory failure, detected using near-infrared spectroscopy–based index, TOxa and transcranial Doppler–based index, Sxa, can predict DCI.

Methods—

In this prospective observational study we enrolled consecutive patients with aneurysmal SAH that occurred <5 days from admission. The primary end point was the occurrence of DCI within 21 days of ictus. The predictive value of autoregulatory disturbances detected in the first 5 days was assessed using univarate proportional hazards model and a multivariate model.

Results—

Ninety-eight patients were included. Univariate analysis demonstrated increased odds of developing DCI when early autoregulation failure was detected (odds ratio [OR], 7.46; 95% confidence interval [CI], 3.03–18.40 and OR, 4.52; 95% CI, 1.84–11.07 for Sxa and TOxa, respectively) but not TCD-vasospasm (OR, 1.36; 95% CI, 0.56–3.33). In a multivariate model Sxa and TOxa remained independent predictors of DCI (OR, 12.66; 95% CI, 2.97–54.07 and OR, 5.34; 95% CI, 1.25–22.84 for Sxa and TOxa, respectively).

Conclusions—

Disturbed autoregulation in the first 5 days after SAH significantly increases the risk of DCI. Autoregulatory disturbances can be detected using near-infrared spectroscopy and transcranial Doppler technologies.
Algorithms as Structural Metaphors: Reflections on the Digital-Cultural Feedback Loop
Authors: Achituv Romy
Published: November 2012

The author argues that the application of digital algorithmic structures to analog media may illuminate hidden values and perceptions inherent in the digital technologies themselves. The paper sets out the understanding of metaphor in contemporary cognitive linguistics, in which metaphor is perceived as a conceptual device that creates meaning through cross-domain mapping—that is, partially mapping (projecting) one conceptual domain onto another. While the projected domain is intended to elucidate the target domain, the author argues that metaphor itself is self-reflexive—drawing attention to characteristics of the projected domain.
The Logic of Color: Theory and Graphics in Christine Ladd-Franklin's Explanation of Color Vision
Authors: Kargon Jeremy
Published: November 2012

In the years after 1870, two theories of color vision vied for primacy: the “trichromatic” theory and a four-color theory, also known as an “opponent” theory of color vision. Among scientists who participated in this debate, mathematician Christine Ladd-Franklin (1847–1930) made special use of graphics as a rhetorical template for reasoning and explanation. Her later work included figures modeled upon novel graphic representations of logical relationships to describe chemical reactions fundamental to visual processes. These and other illustrations demonstrate, in retrospect, how innovation in graphic notation can underlie shifts in the practice and perception of science.
On Headless XP-Movement/Ellipsis
Authors: Funakoshi Kenshi
Published: November 2012

I make two proposals in this article: (a) an economy condition on the operation Copy, which states that Copy should apply to as small an element as possible, and (b) the “two types of head movement” hypothesis, which states that Universal Grammar allows head movement via substitution as well as head movement via adjunction. I argue that with these proposals, we can not only explain two generalizations about what I call headless XPs, but also attribute crosslinguistic variation in the applicability of these generalizations to parameters that are responsible for the availability of multiple specifiers.
VP-Ellipsis Is Not Licensed by VP-Topicalization
Authors: Aelbrecht Lobke , Haegeman Liliane
Published: November 2012

Starting from the observation that the constraints on VP-ellipsis (VPE) closely match those on VP-topicalization (VPT), Johnson (2001) proposes a movement account for VPE: in order for a VP to be deleted, it must first undergo topicalization. We show that although this proposal is attractive, making VPE dependent on VPT is problematic because VPE and VPT are not distributionally equivalent. While VPT targets the left periphery and consequently is subject to constraints on movement, VPE is not so restricted. We outline some alternatives for capturing the observed parallelism in the licensing of VPT and VPE.
Aerosol Impacts on the Microphysical Growth Processes of Orographic Snowfall
Authors: Saleeby Stephen M. , Cotton William R. , Lowenthal Douglas , Messina Joe
Published: November 2012

The Regional Atmospheric Modeling System was used to simulate four winter snowfall events over the Park Range of Colorado. For each event, three hygroscopic aerosol sensitivity simulations were performed with initial aerosol profiles representing clean, moderately polluted, and highly polluted scenarios. Previous work demonstrates that the addition of aerosols can produce a snowfall spillover effect, during events in which riming growth of snow is prevalent in the presence of supercooled liquid water, that is due to a modified orographic cloud containing more numerous but smaller cloud droplets. This study focuses on the detailed microphysical processes that lead to snow growth in each event and how these processes are modulated by the addition of hygroscopic aerosols. A conceptual model of hydrometeor growth processes is presented, along a vertical orographic transect, that reveals zones of vapor deposition of ice and liquid, riming growth, evaporation, sublimation, and regions in which the Wegener–Bergeron–Findeisen (WBF) snow growth process is active. While the aerosol-induced spillover effect is largely determined by the degree of reduction in ice particle riming, an enhancement in the WBF snow growth process under more polluted conditions largely offsets the loss of rime growth, thus leading to a minimal net change in the regional precipitation.
The Modification of Sea Surface Temperature Anomaly Linear Damping Time Scales by Stratocumulus Clouds
Authors: Evan Amato T. , Allen Robert J. , Bennartz Ralf , Vimont Daniel J.
Published: November 2012

Stratocumulus (Sc) cloud cover is a persistent feature of the subtropical North and South Atlantic. It is well known that Sc cloud cover increases with decreasing temperatures of the underlying sea surface and that an increase in cloud cover will cool the surface temperatures via increasing the local albedo, otherwise known as the Sc feedback. In this study observations are used to quantify the magnitude and spatial structure of the Sc feedback in the tropical–extratropical Atlantic Ocean and investigate the role of the Sc feedback in shaping the evolution of coupled modes of variability there. The authors show that in the Atlantic the Sc feedback increases the time scales of Newtonian cooling by 40% and in an idealized linear model of the tropical Atlantic the dominant mode of coupled variability (the Atlantic meridional mode or dipole mode) would experience no transient growth without the influence of the Sc feedback on the surface temperature damping time scales. This study also investigates Atlantic Sc clouds and the Sc feedback in phase 3 of the Coupled Model Intercomparison Project (CMIP3) models. The authors find that most models have negative biases in the mean state of Sc cloud cover and do not reproduce the observed spatial structure of Atlantic Sc clouds. This study also shows that while the majority of models exhibit some agreement with observations in the meridional structure of the Sc feedback, the vast majority of models underestimate the dependence of Sc cloud cover on the underlying SST.
The Transpose-AMIP II Experiment and Its Application to the Understanding of Southern Ocean Cloud Biases in Climate Models
Authors: Williams K. D. , Bodas-Salcedo A. , Déqué M. , Fermepin S. , Medeiros B. , Watanabe M. , Jakob C. , Klein S. A. , Senior C. A. , Williamson D. L.
Published: November 2012

The Transpose-Atmospheric Model Intercomparison Project (AMIP) is an international model intercomparison project in which climate models are run in “weather forecast mode.” The Transpose-AMIP II experiment is run alongside phase 5 of the Coupled Model Intercomparison Project (CMIP5) and allows processes operating in climate models to be evaluated, and the origin of climatological biases to be explored, by examining the evolution of the model from a state in which the large-scale dynamics, temperature, and humidity structures are constrained through use of common analyses.

The Transpose-AMIP II experimental design is presented. The project requests participants to submit a comprehensive set of diagnostics to enable detailed investigation of the models to be performed. An example of the type of analysis that may be undertaken using these diagnostics is illustrated through a study of the development of cloud biases over the Southern Ocean, a region that is problematic for many models. Several models share a climatological bias for too little reflected shortwave radiation from cloud across the region. This is found to mainly occur behind cold fronts and/or on the leading side of transient ridges and to be associated with more stable lower-tropospheric profiles. Investigation of a case study that is typical of the bias and associated meteorological conditions reveals the models to typically simulate cloud that is too optically and physically thin with an inversion that is too low. The evolution of the models within the first few hours suggests that these conditions are particularly sensitive and a positive feedback can develop between the thinning of the cloud layer and boundary layer structure.
An Observation-Based Assessment of Nonlinear Feedback Processes Associated with the Indian Ocean Dipole
Authors: Cai Wenju , Qiu Yun
Published: November 2012

A well-known feature of the Indian Ocean dipole (IOD) is its positive skewness, with cold sea surface temperature (SST) anomalies over the east pole (IODE) exhibiting a larger amplitude than warm SST anomalies. Several mechanisms have been proposed for this asymmetry, but because of a lack of observations the role of various processes remains contentious. Using Argo profiles and other newly available data, the authors provide an observation-based assessment of the IOD skewness. First, the role of a nonlinear dynamical heating process is reaffirmed, which reinforces IODE cold anomalies but damps IODE warm anomalies. This reinforcing effect is greater than the damping effect, further contributing to the skewness. Second, the existence of a thermocline–temperature feedback asymmetry, whereby IODE cold anomalies induced by a shoaling thermocline are greater than warm anomalies associated with a deepening thermocline, is the primary forcing of the IOD skewness. This thermocline–temperature feedback asymmetry is a part of the nonlinear Bjerknes-like positive feedback loop involving winds, SST, and the thermocline, all displaying a consistent asymmetry with a stronger response when IODE SST is anomalously cold. The asymmetry is enhanced by a nonlinear barrier layer response, with a greater thinning associated with IODE cold anomalies than a thickening associated with IODE warm anomalies. Finally, in response to IODE cool anomalies, rainfall and evaporative heat loss diminish and incoming shortwave radiation increases, which results in damping the cool SST anomalies. The damping increases with IODE cold anomalies. Thus, the IOD skewness is generated in spite of a greater damping effect of the SST–cloud–radiation feedback process.
A Comparison of Wind Speed and Forest Damage Associated with Tornadoes in Northern Arizona
Authors: Blanchard David O.
Published: November 2012

Damage surveys in the aftermath of tornadoes occurring in the forested regions of the Mogollon Rim in northern Arizona have been assessed using the enhanced Fujita scale (EF scale) damage indicator (DI) and degree of damage (DOD) tables. These surveys often revealed different DODs within close proximity as well as different spatial patterns and areal extent of tree damage exhibiting the same DOD, making the determination of wind speed and EF-scale ratings challenging. A localized tornado outbreak occurred across northern Arizona on 6 October 2010, producing at least 11 tornadoes and substantial areas of forest damage. Remarkably, one of these tornadoes passed over a three-dimensional sonic anemometer. Wind data from this sensor are compared with tree damage in the adjacent forest to assess the performance of the EF-scale metrics for damage to trees.
Corporate Social Responsibility and Freedom of Association Rights
Authors: Anner Mark
Published: November 2012

Corporations have increasingly turned to voluntary, multi-stakeholder governance programs to monitor workers’ rights and standards in global supply chains. This article argues that the emphasis of these programs varies significantly depending on stakeholder involvement and issue areas under examination. Corporate-influenced programs are more likely to emphasize detection of violations of minimal standards in the areas of wages, hours, and occupational safety and health because focusing on these issues provides corporations with legitimacy and reduces the risks of uncertainty created by activist campaigns. In contrast, these programs are less likely to emphasize workers’ rights to form democratic and independent unions, bargain, and strike because these rights are perceived as lessening managerial control without providing firms with significant reputational value. This argument is explored by coding 805 factory audits of the Fair Labor Association between 2002 and 2010, followed by case studies of Russell Athletic in Honduras, Apple in China, and worker rights monitoring in Vietnam.
Politics of Globalization and National Economy
Authors: Kwon Hyeong-ki
Published: November 2012

This paper examines the globalization process of German core export metalworking industries, to show how the globalization of national corporations has different effects on domestic economies. Contrary to the prevalent views on the globalization of production, this paper holds that the outcomes and patterns of globalization vary, due mainly to the politics of the main actors inside and outside corporations. This paper compares Germany’s negotiated globalization with U.S. employer unilateralism. In most U.S. corporations, employers decide how to globalize based on the short-term perspective of shareholder value. By contrast, in Germany, main industrial actors—including employers, works councils, and trade unions—collectively negotiate how to globalize. In this conflict-laden process of collective negotiation, German actors have created a political compromise that combines the upgrading of domestic production with globalizing overseas, whereas Americans have failed to do so. Furthermore, this paper emphasizes that divergent patterns of globalization are not predetermined by national institutions. To the contrary, the successful outcomes in German globalization come mainly from actors’ proactive readjustments in their traditional model of industrial relations, creating new practices, such as active union involvement in company-level bargaining, and the democratic bottom-up process instead of the traditional top-down process of negotiation.
Narrating history, inventing history: the making of Blindly
Authors: Magris Claudio
Published: November 2012

Magris’s text addresses the circuitous and lengthy creative process that led to the conceptualization and writing of his latest novel Alla cieca (2005; Blindly, 2010). It offers, at same time, a reflection on the core dialectical binary of the work: the relation between inventing History and creating History and thus on the relationship between History and the contemporary novel. Magris sheds light on his own formal and stylistic approach to his text and on his ethical quest among the ideological utopias and individual tragedies of pre- and post-WWII Europe.
Working within the Labyrinth of Race
Authors: McGuire John Thomas
Published: November 2012

Over the past forty years, historians have extensively probed the causes of the historic political realignment of urban African American votes in the United States from 1928 through 1936. In particular, historians such as Evelyn Brooks Higginbotham, Linda Materson, and Deborah Gray White have demonstrated how northern urban African American women shifted their party allegiances. Yet no one has examined whether that realignment continued among this group in the late 1930s and early 1940s. This article uses the brief yet complicated national political career of Crystal Bird Fauset (1893–1965) to demonstrate how black urban women in the United States continued their political realignment while still retaining their agency. Fauset continued the dual strategy previously established by black urban women in the United States, in which a combination of pragmatism and critical detachment enabled its proponents to support political parties without forsaking criticism of those parties’ failures. While Fauset’s personal prickliness played some part in the decline of her national political career, her continuation of the previous strategy eventually prompted her endorsement of Republican candidate Thomas E. Dewey in September 1944. The primary evidence of this process can be seen in her working relationship with Eleanor Roosevelt, which went from close association to total estrangement. This process began during the 1940 national campaign, as Fauset felt slighted by Roosevelt’s seeming exclusion of both herself and black urban women in general, and deepened during the spring and summer of 1944, as Roosevelt increasingly opposed Fauset’s aggressive promotion of African American women voters and civil rights.
When to Use Your Head and When to Use Your Heart
Authors: Gilin Debra , Maddux William W. , Carpenter Jordan , Galinsky Adam D.
Published: November 2012

Four studies explored whether perspective-taking and empathy would be differentially effective in mixed-motive competitions depending on whether the critical skills for success were more cognitively or emotionally based. Study 1 demonstrated that individual differences in perspective-taking, but not empathy, predicted increased distributive and integrative performance in a multiple-round war game that required a clear understanding of an opponent’s strategic intentions. Conversely, both measures and manipulations of empathy proved more advantageous than perspective-taking in a relationship-based coalition game that required identifying the strength of interpersonal connections (Studies 2-3). Study 4 established a key process: perspective-takers were more accurate in cognitive understanding of others, whereas empathy produced stronger accuracy in emotional understanding. Perspective-taking and empathy were each useful but in different types of competitive, mixed-motive situations—their success depended on the task–competency match. These results demonstrate when to use your head versus your heart to achieve the best outcomes for oneself.
Axonal loss of white matter in migraine without aura: A tract-based spatial statistics study
Authors: Yu Dahua , Yuan Kai , Qin Wei , Zhao Ling , Dong Minghao , Liu Peng , Yang Xuejuan , Liu Jixin , Sun Jinbo , Zhou Guangyu , von Deneen Karen M , Tian Jie
Published: November 2012

Aim

Multiple diffusion tensor imaging (DTI) derived indices may help to deduce the pathophysiological type of white matter (WM) changes and provide more specific biomarkers of WM neuropathology in the whole brain of migraine patients without aura (MWoA).

Methods

Twenty MWoA and 20 age-, education- and gender-matched healthy volunteers participated in this study. Tract-based spatial statistics (TBSS) was employed to investigate the WM abnormalities in MWoA by integrating multiple indices, including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD).

Results

Compared with healthy controls, MWoA showed significantly lower FA, MD and AD in multiple brain regions, whereas no difference in RD was observed. Specifically, the overlap among the lower FA, MD, and AD was found in the genu, body, and splenium part of the corpus callosum (CC), the right anterior limb of the internal capsule (ALIC) and the posterior limb of the internal capsule (PLIC) in MWoA compared with healthy controls. Additionally, some of the above WM findings were significantly correlated with duration and headache frequency in MWoA.

Conclusion

Given that decreased AD may suggest axonal loss, our findings may reveal axonal loss in MWoA.
An Intersectional Analysis of Gender and Ethnic Stereotypes
Authors: Ghavami Negin , Peplau Letitia Anne
Published: November 2012

We compared perceived cultural stereotypes of diverse groups varying by gender and ethnicity. Using a free-response procedure, we asked 627 U.S. undergraduates to generate 10 attributes for 1 of 17 groups: Asian Americans, Blacks, Latinos, Middle Eastern Americans, or Whites; men or women; or 10 gender-by-ethnic groups (e.g., Black men or Latina women). Based on intersectionality theory and social dominance theory, we developed and tested three hypotheses. First, consistent with the intersectionality hypothesis, gender-by-ethnic stereotypes contained unique elements that were not the result of adding gender stereotypes to ethnic stereotypes. Second, in support of an ethnicity hypothesis, stereotypes of ethnic groups were generally more similar to stereotypes of the men than of the women in each group. Third, a gender hypothesis postulated that stereotypes of men and women will be most similar to stereotypes of White men and White women, less similar to ethnic minority men and ethnic minority women, and least similar to Black men and Black women. This hypothesis was confirmed for target women, but results for target men were mixed. Collectively, our results contribute to research, theory, and practice by demonstrating that ethnic and gender stereotypes are complex and that the intersections of these social categories produce meaningful differences in the way groups are perceived.
The Effect of Arthroscopic Partial Medial Meniscectomy on Tibiofemoral Stability
Authors: Arno Sally , Hadley Scott , Campbell Kirk A. , Bell Christopher P. , Hall Michael , Beltran Luis S. , Recht Michael P. , Sherman Orrin H. , Walker Peter S.
Published: November 2012

Background:

There is still little known regarding the effects of meniscus resection size on tibiofemoral stability.

Purpose:

To determine if partial medial meniscectomy of the posterior horn significantly alters tibiofemoral stability as measured by the anterior-posterior (AP) position and laxity of the medial femoral condyle.

Study Design:

Controlled laboratory study.

Methods:

Five cadaveric knees were dissected to the capsule, preserving all ligaments and the quadriceps tendon. Each specimen was first tested on a rig where the AP position and laxity of the medial femoral condyle were measured while a range of forces was applied from full extension to 90° of flexion. Magnetic resonance imaging (MRI) at 3 tesla was then performed for baseline measurements of the meniscus before partial meniscectomy. Arthroscopic partial medial meniscectomy aimed at 30% of the posterior horn was then performed, followed by repeat mechanical testing and MRI. The sequence was then repeated for arthroscopic partial meniscectomy aimed at 60% and 100% of the posterior horn of the medial meniscus.

Results:

The MRI analysis demonstrated that 22% ± 9% of the original width of the posterior horn was removed at the first resection, 46% ± 11% was removed at the second resection, and the third resection was 100% removal of the posterior horn for all specimens. After 22% resection, no significant difference in AP laxity was observed. A statistically significant increase in AP laxity was observed with 46% resection under a 500-N compressive load compared with the intact meniscus. After full resection, significant increases in AP laxity were observed under a 50-N compressive load compared with the intact and 22% and 46% resections. The 22% resection had similar AP positions as the intact knee, whereas the 46% resection and 100% removal of the posterior horn had statistically further posterior AP positions than the intact knee.

Conclusion:

Partial medial meniscectomy with ≥46% resection of the original width of the posterior horn significantly altered the AP position of the medial femoral condyle and also increased laxity.

Clinical Relevance:

These mechanical changes may lead to abnormal cartilage loading and early osteoarthritis.
Biomechanical Analysis of Surface-Athlete Impacts on Third-Generation Artificial Turf
Authors: McGhie David , Ettema Gertjan
Published: November 2012

Background:

Excessive repetitive loads are widely believed to be the cause of overload or overuse injuries. On third-generation artificial turf, impacts have been found to vary with surface and shoe properties. Mechanical devices are considered not representative for measuring impact absorption during athletic movements, and pressure insoles have been shown as inaccurate with regard to magnitude of force.

Purpose:

To compare impact properties between different third-generation artificial turf systems in combination with various cleat configurations in vivo using force plate technology.

Study Design:

Controlled laboratory study.

Methods:

Twenty-two male soccer players (mean ± SD: age, 23.1 ± 2.8 y; height, 1.81 ± 0.1 m; body mass, 77.5 ± 6.0 kg) performed 10 short sprints, 5 straight with a sudden stop and 5 with a 90° cut, over a force plate covered with artificial turf for each combination of 3 turf systems and 3 cleat configurations.

Results:

During stop sprints, peak impact was significantly higher on a recreational-level turf system than professional-level turf systems with and without an underlying shock pad (3.12 body weight [ W] vs 3.01 W and 3.02 W, respectively). During cut sprints, peak impact was significantly higher with traditional round cleats than with turf cleats and bladed cleats (2.99 W vs 2.84 W and 2.87 W, respectively).

Conclusion:

The results indicate that both an increase in assumed impact-absorbing surface properties and a larger distribution of shorter cleats produced lower impacts during standardized athletic movements. Regardless, none of the shoe-surface combinations yielded peak impacts of an assumed hazardous magnitude.

Clinical Relevance:

The study provides information on the extent to which various third-generation artificial turf systems and cleat configurations affect impact force, widely believed to be a causative factor for overload and overuse injuries.