bluuebunny/crossref_metadata_2025 huggingface dataset:
Kalirin Promotes Neointimal Hyperplasia by Activating Rac in Smooth Muscle Cells
Authors: Wu Jiao-Hui , Fanaroff Alexander C. , Sharma Krishn C. , Smith Liisa S. , Brian Leigh , Eipper Betty A. , Mains Richard E. , Freedman Neil J. , Zhang Lisheng
Published: January 2013

Objective—

Kalirin is a multifunctional protein that contains 2 guanine nucleotide exchange factor domains for the GTPases Rac1 and RhoA. Variants of
KALRN
have been associated with atherosclerosis in humans, but Kalirin’s activity has been characterized almost exclusively in the central nervous system. We therefore tested the hypothesis that Kalirin functions as a Rho-guanine nucleotide exchange factor in arterial smooth muscle cells (SMCs).

Approach and Results—

Kalirin-9 protein is expressed abundantly in aorta and bone marrow, as well as in cultured SMCs, endothelial cells, and macrophages. Moreover, arterial Kalirin was upregulated during early atherogenesis in apolipoprotein E-deficient mice. In cultured SMCs, signaling was affected similarly in 3 models of Kalirin loss-of-function: heterozygous
Kalrn
deletion, Kalirin RNAi, and treatment with the Kalirin Rho-guanine nucleotide exchange factor -1 inhibitor 1-(3-nitrophenyl)-1H-pyrrole-2,5-dione. With reduced Kalirin function, SMCs showed normal RhoA activation but diminished Rac1 activation, assessed as reduced Rac-GTP levels, p21-activated kinase autophosphorylation, and SMC migration.
Kalrn
–/+
SMCs proliferated 30% less rapidly than wild-type SMCs. Neointimal hyperplasia engendered by carotid endothelial denudation was ≈60% less in
Kalrn
–/+
and SMC-specific
Kalrn
–/+
mice than in control mice.

Conclusion—

Kalirin functions as a guanine nucleotide exchange factor for Rac1 in SMCs, and promotes SMC migration and proliferation both in vitro and in vivo.
Key Role of Estrogens and Endothelial Estrogen Receptor α in Blood Flow–Mediated Remodeling of Resistance Arteries
Authors: Tarhouni K. , Guihot A. L. , Freidja M. L. , Toutain B. , Henrion B. , Baufreton C. , Pinaud F. , Procaccio V. , Grimaud L. , Ayer A. , Loufrani L. , Lenfant F. , Arnal J. F. , Henrion D.
Published: January 2013

Objective—

Flow- (shear stress–)mediated outward remodeling of resistance arteries is involved in collateral growth during postischemic revascularization. As this remodeling is especially important during pregnancy, we hypothesized that estrogens may be involved. A surgical model eliciting a local increase in blood flow in 1 mesenteric resistance artery was used in 3-month-old ovariectomized female rats either treated with 17-β-estradiol (E2) or left untreated.

Methods and Results—

After 14 days, arterial diameter was greater in high-flow arteries than in normal-flow vessels. An ovariectomy suppressed high-flow remodeling, while E2 restored it. High-flow remodeling was absent in mice lacking the estrogen receptor α but not estrogen receptor β. The kinetics of inflammatory marker expression, macrophage infiltration, oxidative stress, and metaloproteinases expression were not altered by the absence of E2 after 2 and 4 days, that is, during remodeling. Nevertheless, E2 was required for the increase in endothelial nitric oxide synthase expression and activation at day 4 when diameter expansion occurs. Finally, the impact of E2 on the endothelium appeared crucial for high-flow remodeling, as this E2 action was abrogated in mice lacking endothelial NOS, as well as in Tie2-Cre(+) ERα
f/f
mice.

Conclusion—

We demonstrate the essential role of E2 and endothelial estrogen receptor α in flow-mediated remodeling of resistance arteries in vivo.
Histone Deacetylase 9 Promotes Angiogenesis by Targeting the Antiangiogenic MicroRNA-17–92 Cluster in Endothelial Cells
Authors: Kaluza David , Kroll Jens , Gesierich Sabine , Manavski Yosif , Boeckel Jes-Niels , Doebele Carmen , Zelent Arthur , Rössig Lothar , Zeiher Andreas M. , Augustin Hellmut G. , Urbich Carmen , Dimmeler Stefanie
Published: January 2013

Objective—

Histone deacetylases (HDACs) modulate gene expression by deacetylation of histone and nonhistone proteins. Several HDACs control angiogenesis, but the role of HDAC9 is unclear.

Methods and Results—

Here, we analyzed the function of HDAC9 in angiogenesis and its involvement in regulating microRNAs. In vitro, silencing of HDAC9 reduces endothelial cell tube formation and sprouting. Furthermore, HDAC9 silencing decreases vessel formation in a spheroid-based Matrigel plug assay in mice and disturbs vascular patterning in zebrafish embryos. Genetic deletion of HDAC9 reduces retinal vessel outgrowth and impairs blood flow recovery after hindlimb ischemia. Consistently, overexpression of HDAC9 increases endothelial cell sprouting, whereas mutant constructs lacking the catalytic domain, the nuclear localization sequence, or sumoylation site show no effect. To determine the mechanism underlying the proangiogenic effect of HDAC9, we measured the expression of the microRNA (miR)-17–92 cluster, which is known for its antiangiogenic activity. We demonstrate that silencing of HDAC9 in endothelial cells increases the expression of miR-17–92. Inhibition of miR-17–20a rescues the sprouting defects induced by HDAC9 silencing in vitro and blocking miR-17 expression partially reverses the disturbed vascular patterning of HDAC9 knockdown in zebrafish embryos.

Conclusion—

We found that HDAC9 promotes angiogenesis and transcriptionally represses the miR-17–92 cluster.
Reduced Atherosclerotic Burden in Subjects With Genetically Determined Low Oxidative Stress
Authors: Violi Francesco , Pignatelli Pasquale , Pignata Claudio , Plebani Alessandro , Rossi Paolo , Sanguigni Valerio , Carnevale Roberto , Soresina Annarosa , Finocchi Andrea , Cirillo Emilia , Catasca Elisa , Angelico Francesco , Loffredo Lorenzo
Published: January 2013

Objective—

NADPH oxidase, one of the most important enzymes producing reactive oxidant species, is suggested to play a role in experimental atherosclerosis, but its role in human atherosclerosis is still unclear. We hypothesized that a reduced activity of NADPH oxidase might be linked to a reduced atherosclerotic burden.

Methods and Results—

Thirty-one women carriers of hereditary deficiency of NOX2, the catalytic subunit of NADPH oxidase, were matched for sex and age with 31 controls and 31 obese women. Flow-mediated dilation and intima-media thickness, 2 surrogate markers of atherosclerosis, serum activity of NOX2, urinary isoprostanes, serum levels of nitrite/nitrate, and platelet production of isoprostanes and nitrite/nitrate were determined. Compared with controls (5.7±3.0% and 0.60±0.11 mm), carriers of NOX2 deficiency had higher flow-mediated dilation (9.2±5.0%;
P
<0.001) and lower intima-media thickness (0.50±0.11 mm;
P
=0.002), whereas obese women had lower flow-mediated dilation (3.2±2.1%;
P
=0.007) and higher intima-media thickness (0.71±0.15 mm;
P
<0.001). Compared with controls, carriers of NOX2 deficiency had lower urinary isoprostanes (132.6±87.3 versus 82.3±46.0 pg/mg creatinine;
P
=0.007) and serum NOX2 activity (24.9±19.3 versus 12.8±11.9 pg/mL;
P
=0.004) and higher serum nitrite/nitrate (23.8±7.6 versus 30.5±6.3 µmol/L;
P
<0.001), whereas obese women had higher urinary isoprostanes (132.6±87.3 versus 182.2±84.6 pg/mg creatinine;
P
=0.008) and serum NOX2 activity (24.9±19.3 versus 36.1±18.6 pg/mL;
P
=0.008) and lower serum nitrite/nitrate (23.8±7.6 versus 12.6±4.2 µmol/L;
P
<0.001). Flow-mediated dilation correlated with intima-media thickness (
r
=–0.433;
P
<0.001), serum NOX2 activity (
r
=–325;
P
<0.001), and urinary isoprostanes (
r
=–0.314;
P
=0.002). Ex vivo study showed that, compared with controls, platelets from carriers of NOX2 deficiency had lower isoprostanes (
P
<0.001) and higher nitrite/nitrate (
P
<0.001), whereas platelets from obese women had higher isoprostanes (
P
<0.001) and lower nitrite/nitrate (
P
=0.013).

Conclusion—

The study shows reduced atherosclerotic burden in carriers of NOX2 deficiency, suggesting that oxidative stress generated by this enzymatic pathway is implicated in human atherosclerosis.
Aberrant Endoplasmic Reticulum Stress in Vascular Smooth Muscle Increases Vascular Contractility and Blood Pressure in Mice Deficient of AMP-Activated Protein Kinase-α2 In Vivo
Authors: Liang Bin , Wang Shuangxi , Wang Qilong , Zhang Wencheng , Viollet Benoit , Zhu Yi , Zou Ming-Hui
Published: January 2013

Objective—

The endoplasmic reticulum (ER) plays a critical role in ensuring proper folding of newly synthesized proteins. Aberrant ER stress is reported to play a causal role in cardiovascular diseases. However, the effects of ER stress on vascular smooth muscle contractility and blood pressure remain unknown. The aim of this study was to investigate whether aberrant ER stress causes abnormal vasoconstriction and consequent high blood pressure in mice.

Methods and Results—

ER stress markers, vascular smooth muscle contractility, and blood pressure were monitored in mice. Incubation of isolated aortic rings with tunicamycin or MG132, 2 structurally unrelated ER stress inducers, significantly increased both phenylephrine-induced vasoconstriction and the phosphorylation of myosin light chain (Thr18/Ser19), both of which were abrogated by pretreatment with chemical chaperones or 5-Aminoimidazole-4-carboxamide ribonucleotide and metformin, 2 potent activators for the AMP-activated protein kinase. Consistently, administration of tauroursodeoxycholic acid or 4-phenyl butyric acid, 2 structurally unrelated chemical chaperones, in AMP-activated protein kinase-α2 knockout mice lowered blood pressure and abolished abnormal vasoconstrictor response of AMP-activated protein kinase-α2 knockout mice to phenylephrine. Consistently, tunicamycin (0.01 μg/g per day) infusion markedly increased both systolic and diastolic blood pressure, both of which were ablated by coadministration of 4-phenyl butyric acid. Furthermore, 4-phenyl butyric acid or tauroursodeoxycholic acid, which suppressed angiotensin II infusion–induced ER stress markers in vivo, markedly lowered blood pressure in angiotensin II–infused mice in vivo.

Conclusion—

We conclude that ER stress increases vascular smooth muscle contractility resulting in high blood pressure, and AMP-activated protein kinase activation mitigates high blood pressure through the suppression of ER stress in vivo.
Notch-Dependent Regulation of the Ischemic Vasodilatory Response—Brief Report
Authors: Chang Alex C.Y. , Patenaude Alexandre , Lu Katherine , Fuller Megan , Ly Michelle , Kyle Alastair , Golbidi Saeid , Wang Yingjin , Walley Keith , Minchinton Andrew , Laher Ismail , Karsan Aly
Published: January 2013

Objective—

We have recently described that Notch activates nitric oxide (NO) signaling in the embryonic endocardium. Both Notch signaling and NO signaling have been shown to be important during adult arteriogenesis. Notch has been shown to be required for remodeling of the collateral vessels, whereas NO is required for the initial vasodilatory response to ischemia. Whether Notch also has an impact on the vasodilatory phase of arteriogenesis after ischemia is not known. We tested the hypothesis that endothelial cell-Notch function is required for NO induction and vasodilation, in response to ischemia in the adult vasculature.

Methods and Results—

We observed a significant decrease in NO levels in the dorsal aorta using a mouse model where Notch was inhibited in endothelial cell in a Tet-inducible fashion. In a femoral artery ligation model, inhibition of endothelial cell-Notch reduced reperfusion and NO generation, as quantified by laser Doppler perfusion imaging and by phosphoendothelial NO synthase, nitrotyrosine, and phosphovasodilator-stimulated phosphoprotein staining, respectively.

Conclusion—

Endothelial Notch activation is required for NO production and reactive vasodilation in a femoral artery ligation model.
Leukocyte-Specific CCL3 Deficiency Inhibits Atherosclerotic Lesion Development by Affecting Neutrophil Accumulation
Authors: de Jager Saskia C.A. , Bot Ilze , Kraaijeveld Adriaan O. , Korporaal Suzanne J.A. , Bot Martine , van Santbrink Peter J. , van Berkel Theo J.C. , Kuiper Johan , Biessen Erik A.L.
Published: January 2013

Objective—

Despite common disbelief that neutrophils are involved in atherosclerosis, evidence is accumulating for a causal role of neutrophils in atherosclerosis. CC chemokine ligand (CCL)3 is an inflammatory chemokine and its expression is significantly increased during atherosclerotic lesion formation in mice. It has recently been shown that under conditions of inflammation neutrophils can migrate along a CCL3 gradient. In this study, we aimed to elucidate the role of leukocyte-derived CCL3 in atherogenesis.

Methods and Results—

Irradiated low density lipoprotein receptor
–/–
mice, reconstituted with CCL3
–/–
or littermate bone marrow showed markedly reduced CCL3 response to lipopolysaccharide treatment, establishing the critical relevance of leukocytes as source of CCL3. Hematopoietic deficiency of CCL3 significantly reduced aortic sinus lesion formation by 31% after 12 weeks of western-type diet. Interestingly, whereas plaque macrophage, collagen, and vascular smooth muscle cell content were unchanged, neutrophil adhesion to and presence in plaques was significantly attenuated in CCL3
–/–
chimeras. These mice had reduced circulating neutrophil numbers, which could be ascribed to an increased neutrophil turnover and CCL3
–/–
neutrophils were shown to be less responsive toward the neutrophil chemoattractant CXC chemokine ligand 1.

Conclusion—

Our data indicate that under conditions of acute inflammation leukocyte-derived CCL3 can induce neutrophil chemotaxis toward the atherosclerotic plaque, thereby accelerating lesion formation.
Pericytes From Infantile Hemangioma Display Proangiogenic Properties and Dysregulated Angiopoietin-1
Authors: Boscolo Elisa , Mulliken John B. , Bischoff Joyce
Published: January 2013

Objective—

Infantile hemangioma (IH) is a rapidly growing vascular tumor affecting newborns. It is composed of immature endothelial cells and pericytes that proliferate into a disorganized mass of blood vessels. We isolated pericytes from IH (Hem-pericytes) to test our hypothesis that Hem-pericytes are unable to stabilize blood vessels.

Methods and Results—

We injected pericytes in vivo, in combination with endothelial cells, and found that Hem-pericytes formed more microvessels compared with control retinal pericytes. We, thereby, analyzed proangiogenic properties of the Hem-pericytes. They grew fast in vitro, and were unable to stabilize endothelial cell growth and migration, and expressed high levels of vascular endothelial growth factor-A compared with retinal pericytes. Hem-pericytes from proliferating phase IH showed lower contractility in vitro, compared with Hem-pericytes from the involuting phase and retinal pericytes. Consistent with a diminished ability to stabilize endothelium, angiopoietin 1 was reduced in Hem-pericytes compared with retinal pericytes. Normal retinal pericytes in which angiopoietin 1 was silenced produced conditioned medium that stimulated endothelial cell proliferation and migration.

Conclusion—

We report the first successful isolation of patient-derived pericytes from IH tissue. Hem-pericytes exhibited proangiogenic properties and low levels of angiopoietin 1, consistent with a diminished ability to stabilize blood vessels in IH.
Smoking-Thrombolysis Paradox
Authors: Kufner Anna , Nolte Christian H. , Galinovic Ivana , Brunecker Peter , Kufner Gerald M. , Endres Matthias , Fiebach Jochen B. , Ebinger Martin
Published: January 2013

Background and Purpose—

The so-called smoking-thrombolysis paradox of an improved outcome after thrombolysis was first described in smokers with myocardial infarction. We investigated whether reperfusion rates and clinical outcome differ between smokers and nonsmokers with ischemic stroke after intravenous tissue plasminogen activator.

Methods—

Consecutive acute ischemic stroke patients, who had magnetic resonance imaging before and 1 day after thrombolysis, were included for analysis. All of the patients received intravenous tissue plasminogen activator within 4.5 hours. Reperfusion was defined as a 75% reduction in perfusion deficit (mean transit time >6 s) after thrombolysis compared with baseline. Magnetic resonance angiography was used to evaluate arterial stenosis and occlusion. Functional outcome was assessed 3 months after stroke using the modified Rankin Score.

Results—

Of 148 patients, 21.6% were smokers (n=32). Smokers were younger (median, 61 years [
SD
, 9.4 years] versus 75 years [
SD
, 11.6 years];
P
<0.001), less often women (28% versus 51%;
P
=0.03), had lower baseline glucose levels (median, 6.2 mmol/L [interquartile range, 5.7–6.8 mmol/L] versus 6.7 mmol/L [interquartile range, 6.1–8.2 mmol/L];
P
<0.01) and higher baseline perfusion deficits (median, 53 mL [interquartile range, 13–141 mL] versus 17 mL [interquartile range, 2–66 mL];
P
=0.04). In a backward stepwise regression analysis including age, sex, hypertension, glucose, perfusion deficit, and smoking, smoking had an odds ratio of 4 (95% confidence interval, 1–16;
P
=0.03) for reperfusion and 6 (95% confidence interval, 1–30;
P
=0.05) for recanalization (regression analysis for recanalization also included localization of arterial occlusion). Smokers had a better outcome (modified Rankin Score=0–2) than nonsmokers (77% versus 55%;
P
=0.05).

Conclusions—

Smoking is independently associated with recanalization and reperfusion, indicating that thrombolytic therapy acts more effectively in smokers; because of small numbers, these results should be considered preliminary.

Clinical Trial Registration—

URL:
http://clinicaltrials.gov
. Unique Identifier: NCT00715533.
The Risk of Stroke or Clinical Impairment After Stereotactic Radiosurgery for ARUBA-Eligible Patients
Authors: Pollock Bruce E. , Link Michael J. , Brown Robert D.
Published: January 2013

Background and Purpose—

The best management of patients with unruptured brain arteriovenous malformations (BAVM) is controversial. In this study, we analyzed the stroke rate and functional outcomes of patients having stereotactic radiosurgery (SRS) for unruptured BAVM using the same eligibility criteria and primary end points as the ARUBA trial.

Methods—

Retrospective observational study of 174 ARUBA-eligible patients having SRS from 1990 to 2005.

Results—

The median follow-up after SRS was 64 months. Fifteen patients (8.7%) had a hemorrhagic stroke at a median of 21 months after SRS. Six patients (3.5%) had a focal neurological deficit and 4 patients died (2.3%). The risk of stroke or death was 10.3% at 5 years and 11.5% at 10 years. Twelve additional patients (6.9%) had a focal neurological deficit from either radiation-related complications (n=7) or subsequent resection (n=5). The risk of patients’ having clinical impairment (modified Rankin Score ≥2) was 8.4% at 5 years and 12.0% at 10 years. Increasing BAVM volume was associated with both stroke or death (hazard ratio=1.06; 95% confidence interval, 1.0–1.11;
P
=0.04) and clinical impairment (hazard ratio=1.06; 95% confidence interval, 1.01–1.09;
P
=0.01). The 10-year risk of stroke or death and clinical impairment for patients with BAVM ≤5.6 cm
3
was 5% and 4%, respectively.

Conclusions—

The observed risk of stroke or death after SRS was approximately 2% per year for the first 5 years after SRS, declining to 0.2% annually for years 6 to 10. Patients with small volume BAVM may benefit from SRS compared with the natural history of unruptured BAVM over the planned follow-up interval of the ARUBA trial (5–10 years).
Mesenchymal Stem Cells Prevent Hydrocephalus After Severe Intraventricular Hemorrhage
Authors: Ahn So Yoon , Chang Yun Sil , Sung Dong Kyung , Sung Se In , Yoo Hye Soo , Lee Jung Hee , Oh Won Il , Park Won Soon
Published: January 2013

Background and Purpose—

Severe intraventricular hemorrhage (IVH) in premature infants and the ensuing posthemorrhagic hydrocephalus cause significant mortality and neurological disabilities, and there are currently no effective therapies. This study determined whether intraventricular transplantation of human umbilical cord blood-derived mesenchymal stem cells prevents posthemorrhagic hydrocephalus development and attenuates brain damage after severe IVH in newborn rats.

Methods—

To induce severe IVH, 100 μL of blood was injected into each lateral ventricle of postnatal day 4 (P4) Sprague-Dawley rats. Human umbilical cord blood-derived mesenchymal stem cells or fibroblasts (1×10
5
) were transplanted intraventricularly under stereotaxic guidance at P6. Serial brain MRI and behavioral function tests, such as the negative geotaxis test and rotarod test, were performed. At P32, brain tissue and cerebrospinal fluid were obtained for histological and biochemical analyses.

Results—

Intraventricular transplantation of umbilical cord blood-derived mesenchymal stem cells, but not fibroblasts, prevented posthemorrhagic hydrocephalus development and significantly attenuated impairment on behavioral tests; the increased terminal deoxynycleotidyltransferase-mediated deoxyuridine triphosphate nick end labeling-positive cells; increased expression of inflammatory cytokines, such as interleukin-1α, interleukin-1β, interleukin-6, and tumor necrosis factor-α; increased astrogliosis; and reduced corpus callosal thickness and myelin basic protein expression after inducing severe IVH.

Conclusions—

Intraventricular transplantation of umbilical cord blood-derived mesenchymal stem cells significantly attenuated the posthemorrhagic hydrocephalus and brain injury after IVH. This neuroprotective mechanism appears to be mediated by the anti-inflammatory effects of these cells.
Have Aerosols Caused the Observed Atlantic Multidecadal Variability?
Authors: Zhang Rong , Delworth Thomas L. , Sutton Rowan , Hodson Daniel L. R. , Dixon Keith W. , Held Isaac M. , Kushnir Yochanan , Marshall John , Ming Yi , Msadek Rym , Robson Jon , Rosati Anthony J. , Ting MingFang , Vecchi Gabriel A.
Published: January 2013

Identifying the prime drivers of the twentieth-century multidecadal variability in the Atlantic Ocean is crucial for predicting how the Atlantic will evolve in the coming decades and the resulting broad impacts on weather and precipitation patterns around the globe. Recently, Booth et al. showed that the Hadley Centre Global Environmental Model, version 2, Earth system configuration (HadGEM2-ES) closely reproduces the observed multidecadal variations of area-averaged North Atlantic sea surface temperature in the twentieth century. The multidecadal variations simulated in HadGEM2-ES are primarily driven by aerosol indirect effects that modify net surface shortwave radiation. On the basis of these results, Booth et al. concluded that aerosols are a prime driver of twentieth-century North Atlantic climate variability. However, here it is shown that there are major discrepancies between the HadGEM2-ES simulations and observations in the North Atlantic upper-ocean heat content, in the spatial pattern of multidecadal SST changes within and outside the North Atlantic, and in the subpolar North Atlantic sea surface salinity. These discrepancies may be strongly influenced by, and indeed in large part caused by, aerosol effects. It is also shown that the aerosol effects simulated in HadGEM2-ES cannot account for the observed anticorrelation between detrended multidecadal surface and subsurface temperature variations in the tropical North Atlantic. These discrepancies cast considerable doubt on the claim that aerosol forcing drives the bulk of this multidecadal variability.
Wave-Breaking Characteristics of Northern Hemisphere Winter Blocking: A Two-Dimensional Approach
Authors: Masato Giacomo , Hoskins Brian J. , Woollings Tim
Published: January 2013

This paper generalizes and applies recently developed blocking diagnostics in a two-dimensional (2D) latitude–longitude context, which takes into consideration both mid- and high-latitude blocking. These diagnostics identify characteristics of the associated wave breaking as seen in the potential temperature θ on the dynamical tropopause, particularly the cyclonic or anticyclonic direction of wave breaking (“DB index”) and the relative intensity (“RI index”) of the air masses that contribute to blocking formation. The methodology is extended to a 2D domain and a cluster technique is deployed to classify mid- and high-latitude blocking according to the wave-breaking characteristics. Midlatitude blocking is observed over Europe and Asia, where the meridional gradient of θ is generally weak, whereas high-latitude blocking is mainly present over the oceans, to the north of the jet stream, where the meridional gradient of θ is much stronger. They occur on the equatorward and poleward flank of the jet stream, respectively, where the horizontal shear ∂u/∂y is positive in the first case and negative in the second case. A regional analysis is also conducted. Warm-cyclonic blocking over the Pacific and cold-anticyclonic blocking over Europe are identified as the most persistent types and are associated with large amplitude anomalies in temperature and precipitation. Finally, the high-latitude cyclonic events seem to correlate well with low-frequency modes of variability over the Pacific and Atlantic Oceans.
Southward Intertropical Convergence Zone Shifts and Implications for an Atmospheric Bipolar Seesaw
Authors: Cvijanovic Ivana , Langen Peter L. , Kaas Eigil , Ditlevsen Peter D.
Published: January 2013

In this study, southward intertropical convergence zone (ITCZ) shifts are investigated in three different scenarios: Northern Hemispheric cooling, Southern Hemispheric warming, and a bipolar seesaw-like forcing that combines the latter two. The experiments demonstrate the mutual effects that northern- and southern-high-latitude forcings exert on tropical precipitation, suggesting a time-scale-dependent dominance of northern versus southern forcings. In accordance with this, two-phase tropical precipitation shifts are suggested, involving a fast component dominated by the high-northern-latitude forcing and a slower component due to the southern-high-latitude forcing. The results may thus be useful for the future understanding and interpretation of high-resolution tropical paleoprecipitation proxies and their relation to high-latitude records (e.g., ice core data). The experiments also show that Southern Ocean warming has a global impact, affecting both the tropics and northern extratropics, as seen in a southward ITCZ shift and mid- and high-latitude North Atlantic surface temperature and wind changes. In terms of dynamical considerations, the tropical circulation response to high-latitude forcing is found to be nonlinear: the atmospheric heat transport and Hadley cell anomalies differ significantly (in magnitude) when comparing the warming and cooling experiments. These are related to different interhemispheric temperature gradients that are altered mainly by nonlinearities in water vapor response. Decomposition of the top-of-the-atmosphere flux response into atmospheric feedback effects shows the dominance of water vapor and cloud feedbacks in the tropics, with the longwave cloud feedback effect governing the overall cloud response.
Test of a Method for Monitoring the Geostrophic Meridional Overturning Circulation Using Only Boundary Measurements
Authors: Hughes Chris W. , Elipot Shane , Morales Maqueda Miguel Ángel , Loder John W.
Published: January 2013

Measurements of ocean bottom pressure, particularly on the continental slope, make an efficient means of monitoring large-scale integrals of the ocean circulation. However, direct pressure measurements are limited to monitoring relatively short time scales (compared to the deployment period) because of problems with sensor drift. Measurements are used from the northwest Atlantic continental slope, as part of the Rapid Climate Change (RAPID)–West Atlantic Variability Experiment, to demonstrate that the drift problem can be overcome by using near-boundary measurements of density and velocity to reconstruct bottom pressure differences with accuracy better than 1 cm of water (100 Pa). This accuracy permits the measurement of changes in the zonally integrated flow, below and relative to 1100 m, to an accuracy of 1 Sv (1 Sv ≡ 106 m3 s−1) or better. The technique employs the “stepping method,” a generalization of hydrostatic balance for sloping paths that uses geostrophic current measurements to reconstruct the horizontal component of the pressure gradient.
Electric Field Reversal in Sprite Electric Field Signature
Authors: Sonnenfeld Richard G. , Hager William W.
Published: January 2013

In measurements of the electric field associated with the current of a sprite 450 km from ground-based field sensors, it was observed that the sign of the electric field was positive when positive charge was lowered from the ionosphere. A recent model for the electric field associated with the sprite current also predicts positive field changes at 450 km from the sprite. A well-known analysis of a vertical dipole in a thundercloud shows that the electric field on the ground reverses its sign at an easily computed distance from the dipole. A similar simplified electrostatic analysis of a sprite predicts a field reversal distance around 130 km. A more accurate electrodynamic analysis based on Maxwell’s equations indicates that the field reversal distance should be between 70 and 80 km.
Accessing STEM-Focused Education
Authors: Rogers-Chapman M. Felicity
Published: January 2013

In recent years, policy makers, researchers, and educators have focused on the preparation of individuals in STEM (science, technology, engineering, and mathematics) fields. One popular policy lever is STEM-focused high schools. The purpose of this study is to identify which student populations have access to STEM secondary schools. By comparing STEM high schools to neighborhood schools and districts, this study finds access to STEM high schools to be unevenly distributed. Among the key findings is that STEM high schools tend to have fewer students from disadvantaged groups than their district averages. Furthermore, I find that African Americans are disproportionately represented in admissions-only STEM high schools. As funding for more STEM high schools is allocated and infused into the system, it is important to identify locations and groups that may benefit and currently lack access to STEM high schools. Decision makers would be wise to place future STEM high schools in areas with high percentages of Latino students who may benefit from these unique programs.
Marginalisation of Muslim Writers in South Asian Literature: Rokeya Sakhawat Hossain’s English Works
Authors: Hasan Md. Mahmudul
Published: January 2013

This article argues that there appears to be a pattern of disregarding the literary contributions of South Asian Muslim writers who produced English texts on a variety of topics. It then mainly contextualises Rokeya Sakhawat Hossain’s English works in the tradition of South Asian writing in English to identify a continuous trend of undervaluing Muslim literary contributions in English in the region. The article thus argues for a re-assessment of the evaluation of this literary tradition, so that the many forgotten South Asian Muslim writers in English, including Rokeya, regain their long overdue recognition.
Cosmopolitanism and the Morality of Business among Navi Mumbai Merchants
Authors: Taguchi Yoko
Published: January 2013

Based on anthropological fieldwork, this article confirms that arguments about the decline of Mumbai’s cosmopolitanism through the rise of regionalism and hindutva have failed to consider the idea of ‘cosmopolitanism’ as understood and used by local people, specifically local merchants. Reconsideration of cosmopolitanism in relation to regionalism focuses on the morality of business, as expressed by merchants in Navi Mumbai, is examined through two case scenarios. The Marathisation of signboards led by the Maharashtra Navnirman Sena (MNS) and participation in the Ganesh Festival show that their morality of business enables Navi Mumbai’s merchants to adjust to various kinds of challenging phenomena, including those seen as regionalism. The same business morality, then, skillfully re-constructs the foundations of cosmopolitanism as a polyphonic folk term.
Literary Self-Determination and The Disciplinary Boundaries of Hindi Literature in the Early Twentieth Century
Authors: Mody Sujata S.
Published: January 2013

This article examines Mahavir Prasad Dwivedi’s project of literary self-determination, as articulated in two programmatic essays published in the Hindi journal Sarasvati under his editorship (1903–1920), scrutinising his construction of literature as a culturally embedded category of national consequence. His theorisation of Hindi literature as broadly inclusive in terms of its basic definition and function supported the growth of what he considered a national treasury of literature. His discussion of its historical and linguistic parameters and his emphasis on a prioritised plan of literary production, reified the notion of a modern discipline oriented towards a narrowly constructed national collective that sought to establish its sovereign identity via literature in Khari Boli Hindi. Though not explicit in its anti-colonial nationalism, this project nevertheless privileged Hindi as the projected lead language of a modern sovereign nation, with all the risks that delimitation entailed.
Community Forest Management in Colonial and Postcolonial South India: Policy and Practice
Authors: Kumar V.M. Ravi
Published: January 2013

In the past two decades, South Asia has undergone robust reforms in the forestry sector which claim to be initiating a transformation from state-centric to people-centric forest management. This shift is perceived as an important move towards decolonisation in governance processes in India. Examining the forest policies in colonial and postcolonial South India, this article finds, however, that community forest management in postcolonial India remains substantially rooted in the colonial framework of forest resource management policies. In practice, this means that exploitation of forests gives some consideration to the requirements of forest-dependent communities today, but does so now under the control of a state that fails to protect the most basic rights of many of its most vulnerable citizens. The article thus argues critically that supposedly people-centric community forest management in India is not sensitive enough to local development needs, nor indeed sufficiently protective of the basic needs of many forest-dependent people.
Introduction: Georg Simmel’s ‘Sociological Metaphysics’: Money, Sociality, and Precarious Life
Authors: Harrington Austin , Kemple Thomas M.
Published: January 2013

The articles brought together in this double-length section of the Annual Review of Theory, Culture & Society focus on two intertwined strands of the thought of Georg Simmel, both of them neglected until recent years. A first bears on what might be called Simmel’s metaphysics of the social, or what he himself once called ‘sociological metaphysics’. A second strand centres on the renewed contemporary relevance of Simmel’s ideas about money economies and their relation to precarious individual life-situations in an age of global economic turbulence. Current sensibilities in the wake of global economic crisis and the demise of some of the more euphoric sociologies of globalization of the last two decades provide a timely setting for a reappraisal of Simmel’s thinking. With the completion in 2012 of the Suhrkamp edition of Simmel’s collected works, Simmel’s themes need to be explored more deeply, including particularly his thinking about lived experience, transcendence, death, fragmentary worlds of value, and allegorical representation. This issue of the journal showcases some of the latest scholarly work and foregrounds several pivotal primary pieces unavailable in English until now.
Bashir Makhoul’s Installation Enter Ghost, Exit Ghost: The Revenge of Images or Imaging
Authors: Jin Huimin
Published: January 2013

Bashir Makhoul is a Palestinian British artist whose recent installation titled Enter Ghost, Exit Ghost contains the theme of ‘revenge’. It essentially advocates the return to ‘identity’ and ‘land’. This is obviously Makhoul’s politics, but it can only belong to politics through art. Makhoul has adopted the stage directions of Hamlet, involving his work with a political project on the one hand, while on the other hand turning such a project into a ‘ghost’ and a series of ghostly images. Thus, the political revenge becomes the revenge of images. In other words, politics becomes art here. But this artistic politics doesn’t mean the castration or abandonment of politics. To Makhoul, it is an artistic means by which to engage politics, an alternative way to look at politics, which is based upon the conviction that politics should have its emotional and affective dimension.
On the Genesis of a Collected Edition of Simmel’s Works, 1918–2012
Authors: Rammstedt Otthein
Published: January 2013

The article records the three stages of work undertaken to assemble a single organized corpus of Simmel’s dispersed writings after his death in September 1918. This incudes a first phase of work by Gertrud Simmel and Gertrud Kantorowicz from the years of the Weimar Republic, a second phase from the post-1945 period, overseen by Michael Landmann and Kurt Gassen, and a third phase, inaugurated in the 1980s by a team of scholars at Bielefeld University headed by Otthein Rammstedt and – initially – Niklas Luhmann, which resulted in the 24 volumes in print today with Suhrkamp Verlag.
Comparison of Drop Jumps and Sport-Specific Sidestep Cutting
Authors: Kristianslund Eirik , Krosshaug Tron
Published: January 2013

Background:

Anterior cruciate ligament (ACL) injuries are a serious problem, with a high incidence and serious consequences. Published clinical screening tests are based on 2-legged and controlled drop jumps, but ACL injuries are known to occur in single-legged landings and sidestep cutting, where the load is predominantly distributed to a single leg.

Purpose:

To describe knee kinematics and kinetics in drop jumps and sidestep cutting and investigate the rank correlation of knee valgus angles and knee abduction moments between and within these movements.

Study Design:

Controlled laboratory study.

Methods:

A total of 120 elite female handball players (mean ± SD: age, 22.4 ± 7.1 years; height, 171 ± 7 cm; weight, 67 ± 7 kg), each performed 3 drop jumps and 3 sport-specific sidestep cuts to each side. Kinematics and kinetics were calculated from high-speed 3-dimensional motion analysis.

Results:

Knee kinematics and kinetics were significantly different between drop jumps and sidestep cutting. The knee abduction moment was 6 times higher in sidestep cutting (1.58 ± 0.60 Nm/kg vs 0.25 ± 0.16 Nm/kg). There was a poor correlation between knee abduction moments (ρ = 0.135) in the 2 tasks, but a moderate correlation (ρ = 0.706) for knee valgus angles. There was a poor correlation between knee valgus angles in drop jumps and knee abduction moments in sidestep cuts (ρ = 0.238).

Conclusion:

Motion patterns are different between drop jumps and sidestep cutting. There is a moderate correlation for knee abduction moments between the 2 tasks, but knee abduction moments are less consistent across tasks.

Clinical Relevance:

Knee valgus angles during drop jumps do not predict knee abduction moments during sidestep cutting. The moderate correlation of knee valgus angles in drop jumps and sidestep cutting indicates that this measure may be more relevant for screening efforts.
Influence of inorganic fillers on the fire protection of intumescent coatings
Authors: Duquesne Sophie , Bachelet Pierre , Bellayer Séverine , Bourbigot Serge , Mertens William
Published: January 2013

Intumescent coatings, mainly composed of ammonium polyphosphate, pentaerythritol and melamine, are widely used in the field of fire protection of steel structures. The objective of this study was to investigate how the presence of two different inorganic fillers (titanium dioxide and mineral fibres) will affect the fire performance of an acrylic-based intumescent coating. In both cases, it was observed that the inorganic filler enabled improvement of the fire-protective behaviour of intumescent paints, maintaining their performance for a longer time. The mode of action was attributed to reinforcement of the char due to the presence of the fillers.
Nonalcoholic Fatty Liver Disease and the Metabolic Syndrome
Authors: Rahimi Robert S. , Landaverde Carmen
Published: January 2013

The prevalence of nonalcoholic fatty liver disease (NAFLD) is expected to rise along with the global obesity epidemic. As NAFLD is the most common cause of chronic liver disease in the United States, it has become a major health concern. It affects all ethnicities, with the highest prevalence among the Hispanic population. Individuals with nonalcoholic steatohepatitis (NASH), the more serious form of NAFLD, are at increased risk of developing cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Since NAFLD is intricately associated with the metabolic syndrome and insulin resistance, increased risk of cardiovascular disease and mortality become a real concern. It has recently been shown that current nutrition trends, such as increased consumption of high‐fructose corn syrup and certain types of fats, may have an important role in the increased NAFLD prevalence. As there are no ideal treatment options available for NAFLD, a multifaceted treatment approach should be tailored to each individual patient.
Convergence, Divergence, or Constancy of Spatial Planning? Connecting Theoretical Concepts with Empirical Evidence from Europe
Authors: Stead Dominic
Published: January 2013

Spatial planning across much of the world is experiencing reform in response to common challenges of globalization, sustainable development, economic competitiveness, economic reforms, and demographic change. In Europe, greater transnational networking and cooperation on spatial planning, often facilitated by European initiatives, have resulted in planning policy makers at different levels being increasingly influenced and exposed to policies and practices from elsewhere. These processes might be assumed to be leading to some sort of convergence of spatial planning policy. However, this is not necessarily the case: there are deeply embedded differences between nations in terms of political, professional, and administrative cultures and structures. There are also significant differences in social models and welfare systems across Europe, as well as different histories. These differences, which are explored conceptually and empirically in this article, potentially put a brake on the idea of the convergence or harmonization of national and sub-national arrangements for spatial planning.
Harnessing University Entrepreneurship for Economic Growth
Authors: Hayter Christopher S.
Published: January 2013

University spin-offs are an important vehicle for knowledge dissemination and have the potential to generate jobs and economic growth. Despite their importance, little research exists on spin-off performance or impact, especially from the perspective of academic entrepreneurs. Using logit regression, this article makes a scholarly contribution by testing the relationship between spin-off success—defined here as technology commercialization—and multiple factors derived from the extant literature. Several significant variables are found to enable commercialization success within the sample, including venture capital, multiple and external licenses, outside management, joint ventures with other companies, previous faculty consulting experience, and—surprisingly—a negative relationship to post-spin-off services provided by universities. The results have important implications for public policy and management, supporting an overall “open innovation” approach to spin-off success.
Cluster Sustainability
Authors: Breznitz Shiri M.
Published: January 2013

In the past two decades, many industrial districts have become more specialized in particular stages of production. Two related processes contribute to this specialization: globalization and fragmentation of production. Hence, this article asks the following question: Can an industry centered on one part of the production cycle become sustainable? This article examines an innovation-based cluster: the life sciences industry in Israel. This industry is based on innovative companies, with strong ties to university research. A majority of companies in Israel are small and focus on R&D. Following a series of in-depth interviews, site visits, and a survey, this article strengthens the perception that innovation can be the basis of an industry, but it may not be sufficient for sustainability. To achieve further development and regional growth, companies require additional factors in the form of other companies at different stages of production, which are supported by policy, funding, and expertise.
Settlement of ballasted track under traffic loading: Application to transition zones
Authors: Varandas José N , Hölscher Paul , Silva Manuel AG
Published: January 2013

Transition zones corresponding to the passage from railway tracks on embankment to natural ground or settlement free structures are frequently problematic for maintenance. Changing stiffness of the track and differential settlements are the main causes for the degradation of tracks and foundations at transitions. This paper presents a methodology to predict the settlement of the track due to train loading, applicable to transition zones. The methodology is based on dynamic calculations using a (non-linear) train–track interaction model and an incremental settlement model. Important non-linear aspects in dynamic models for railway transitions are the loss of contact between the sleepers and the ballast and the non-linear constitutive behaviour of the ballast. The settlements are calculated paying attention to the factors that most influence the long-term behaviour of ballast, such as the amplitude of the applied dynamic force and the number of loading cycles. The importance of the dynamic loading from the trains and of the constitutive models used for the trackbed layers is analysed.
Positive Clinical Neuroscience
Authors: Kapur Narinder , Cole Jonathan , Manly Tom , Viskontas Indre , Ninteman Aafke , Hasher Lynn , Pascual-Leone Alvaro
Published: January 2013

Disorders of the brain and its sensory organs have traditionally been associated with deficits in movement, perception, cognition, emotion, and behavior. It is increasingly evident, however, that positive phenomena may also occur in such conditions, with implications for the individual, science, medicine, and for society. This article provides a selective review of such positive phenomena – enhanced function after brain lesions, better-than-normal performance in people with sensory loss, creativity associated with neurological disease, and enhanced performance associated with aging. We propose that, akin to the well-established field of positive psychology and the emerging field of positive clinical psychology, the nascent fields of positive neurology and positive neuropsychology offer new avenues to understand brain-behavior relationships, with both theoretical and therapeutic implications.