bluuebunny/crossref_metadata_2025 huggingface dataset:
MILNOR FIBRATIONS AND d-REGULARITY FOR REAL ANALYTIC SINGULARITIES
Authors: CISNEROS-MOLINA J. L. , SEADE J. , SNOUSSI J.
Published: April 2010

We study Milnor fibrations of real analytic maps [Formula: see text], n ≥ p, with an isolated critical value. We do so by looking at a pencil associated canonically to every such map, with axis V = f-1(0). The elements of this pencil are all analytic varieties with singular set contained in V. We introduce the concept of d-regularity, which means that away from the axis each element of the pencil is transverse to all sufficiently small spheres. We show that if V has dimension 0, or if f has the Thom af-property, then f is d-regular if and only if it has a Milnor fibration on every sufficiently small sphere, with projection map f/‖f‖. Our results include the case when f has an isolated critical point. Furthermore, we show that if f is d-regular, then its Milnor fibration on the sphere is equivalent to its fibration on a Milnor tube. To prove these fibration theorems we introduce the spherefication map, which is rather useful to study Milnor fibrations. It is defined away from V; one of its main properties is that it is a submersion if and only if f is d-regular. Here restricted to each sphere in ℝn the spherefication gives a fiber bundle equivalent to the Milnor fibration.
BUBBLING LOCATION FOR SEQUENCES OF APPROXIMATE f-HARMONIC MAPS FROM SURFACES
Authors: LI YUXIANG , WANG YOUDE
Published: April 2010

Let f be a positive smooth function on a closed Riemann surface (M, g). The f-energy of a map u from M to a Riemannian manifold (N, h) is defined as [Formula: see text] and its L2-gradient is: [Formula: see text] We will study the blow-up properties of some approximate f-harmonic map sequences in this paper. For a sequence uk : M → N with ‖τf(uk)‖L2 < C1 and Ef(uk) < C2, we will show that, if the sequence is not compact, then it must blow-up at some critical points of f or some concentrate points of |τf(uk)|2dVg. For a minimizing α-f-harmonic map sequence in some homotopy class of maps from M into N we show that, if the sequence is not compact, the blow-up points must be the minimal point of f and the energy identity holds true.
CRITICAL SLOWING DOWN ALONG THE DYNAMIC PHASE BOUNDARY IN ISING MEANFIELD DYNAMICS
Authors: ACHARYYA MUKTISH , ACHARYYA AJANTA BHOWAL
Published: April 2010

We studied the dynamical phase transition in kinetic Ising ferromagnets driven by oscillating magnetic field in meanfield approximation. The meanfield differential equation was solved by sixth-order Runge–Kutta–Felberg method. The time-averaged magnetization plays the role of the dynamic order parameter. We studied the relaxation behavior of the dynamic order parameter close to the transition temperature, which depends on the amplitude of the applied magnetic field. We observed the critical slowing down along the dynamic phase boundary. We proposed a power law divergence of the relaxation time and estimated the exponent. We also found its dependence on the field amplitude and compared the result with the exact value in limiting case.
MODELING A NONLINEAR LIQUID LEVEL SYSTEM BY CELLULAR NEURAL NETWORKS
Authors: HERNANDEZ-ROMERO NORBERTO , SECK-TUOH-MORA JUAN CARLOS , GONZALEZ-HERNANDEZ MANUEL , MEDINA-MARIN JOSELITO , FLORES-ROMERO JUAN JOSE
Published: April 2010

This paper presents the analogue simulation of a nonlinear liquid level system composed by two tanks; the system is controlled using the methodology of exact linearization via state feedback by cellular neural networks (CNNs). The relevance of this manuscript is to show how a block diagram representing the analogue modeling and control of a nonlinear dynamical system, can be implemented and regulated by CNNs, whose cells may contain numerical values or arithmetic and control operations. In this way the dynamical system is modeled by a set of local-interacting elements without need of a central supervisor.
EVOLUTIONARY TOPOLOGY OF A CURRENCY NETWORK IN ASIA
Authors: FENG XIAOBING , WANG XIAOFAN
Published: April 2010

Although recently there are extensive research on currency network using minimum spanning trees approach, the knowledge about the actual evolution of a currency web in Asia is still limited. In the paper, we study the structural evolution of an Asian network using daily exchange rate data. It was found that the correlation between Asian currencies and US Dollar, the previous regional key currency has become weaker and the intra-Asia interactions have increased. This becomes more salient after the exchange rate reform of China. Different from the previous studies, we further reveal that it is the trade volume, national wealth gap and countries growth cycle that has contributed to the evolutionary topology of the minimum spanning tree. These findings provide a valuable platform for theoretical modeling and further analysis.
A CELLULAR AUTOMATA MODEL OF TRAFFIC FLOW WITH CONSIDERATION OF THE INERTIAL DRIVING BEHAVIOR
Authors: DING JIAN-XUN , HUANG HAI-JUN
Published: April 2010

The inertial driving behavior, although observed in real traffic, has not been deeply understood in most previous studies. In this paper we propose a cellular automata model of the traffic on a single lane highway which considers the drivers' inertial behavior under different driving circumstances. Simulation results show that our model can capture such important features of the traffic as jam formation, phase transition and metastable states. Some of other models, like the slow-to-start model, can be derived from our model.
SPONTANEOUS REORIENTATIONS IN A MODEL OF OPINION DYNAMICS WITH ANTICONFORMISTS
Authors: KONDRAT GRZEGORZ , SZNAJD-WERON KATARZYNA
Published: April 2010

In this paper we investigate a model (based on the idea of the outflow dynamics), in which only conformity and anticonformity can lead to the opinion change. We show that for low level of anticonformity the consensus is still reachable but spontaneous reorientations between two types of consensus ("all say yes" or "all say no") appear.
Angiotensin II signaling through the AT1a and AT1b receptors does not have a role in the development of cerulein-induced chronic pancreatitis in the mouse
Authors: Ulmasov Barbara , Xu Zekuan , Talkad Vanita , Oshima Kiyoko , Neuschwander-Tetri Brent A.
Published: April 2010

The intraorgan renin-angiotensin system (RAS) plays an important role in the pathophysiology of a variety of diseases and has been implicated in fibrogenesis. The role of RAS in the development of chronic pancreatitis is not well established. The blockade of RAS in rat models with angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor 1 (AT1) blockers (ARBs) mostly have reduced pancreatic inflammation and fibrosis with a few exceptions. At the same time, the use of ACEi and ARBs in humans is associated with a modest risk of acute pancreatitis. The aim of this study was to elucidate the effect of the AT1 signaling pathway in the development of pancreatitis using AT1a- and AT1b-deficient mice as well as the ARB losartan. Chronic pancreatitis was induced by repetitive cerulein administration in C57BL/6J wild-type (WT) and AT1a- and AT1b-deficient mice (AT1a−/− and AT1b−/−), and pancreatic injury was assessed at day 10. Pancreatic weight of cerulein treated groups was significantly reduced. There was severe parenchymal atrophy and fibrosis assessed by histological examination. Fibrosis was accompanied by activation of pancreatic stellate cells (PSC) evaluated by Western blot analysis for α-smooth muscle actin. No differences were seen between cerulein-treated WT, AT1a−/− , AT1b−/− mice, or losartan treated-WT mice with regards to morphological or molecular alterations induced by cerulein. Our results demonstrate that AT1a and AT1b receptor pathways do not seem to be essential for the development of pancreatitis in the mouse model of pancreatitis induced by repetitive cerulein injury.
Inducible activation of Cre recombinase in adult mice causes gastric epithelial atrophy, metaplasia, and regenerative changes in the absence of “floxed” alleles
Authors: Jae Huh Won , Mysorekar Indira U. , Mills Jason C.
Published: April 2010

The epithelium of the mammalian gastric body comprises multiple cell types replenished by a single stem cell. The adult conformation of cell lineages occurs well after birth; hence, study of genes regulating stem cell activity is facilitated by inducible systems for gene deletion. However, there is a potential pitfall involving the commonly used inducible Cre recombinase system to delete genes: we report here that induction of Cre using standard doses of tamoxifen led to marked spasmolytic polypeptide-expressing metaplasia of the stomach within days and profound atrophy of the entire epithelium with foci of hyperplasia by 2 wk even in the absence of loxP-flanked alleles. Cre induction caused genotoxicity with TdT-mediated dUTP nick-end labeling (TUNEL)-positive apoptosis (TUNEL-positive cells) and increased levels of DNA damage markers (γH2AX, p53, DDIT3, GADD45A). Although Cre was expressed globally by use of a chicken actin promoter, the effects were almost entirely stomach specific. Despite severe injury, a subset of mice showed near complete healing of the gastric mucosa 11–12 wk after Cre induction, suggesting substantial gastric regenerative capacity. Finally, we show that nongenotoxic doses of tamoxifen could be used to specifically delete loxP-flanked Bmpr1a, the receptor for bone morphogenetic protein 2, 4, and 7, causing antral polyps and marked antral-pyloric hyperplasia, consistent with previous reports on Bmpr1a. Together, the results show dose-dependent, potentially reversible sensitivity of the gastric mucosa to Cre genotoxicity. Thus we propose that tamoxifen induction of Cre could be used to induce genotoxic injury to study the regenerative capacity of the gastric epithelial stem cell.
ABCG5/ABCG8-independent biliary cholesterol excretion in lactating rats
Authors: Coy Donna J. , Wooton-Kee Clavia R. , Yan Baoxiang , Sabeva Nadezhda , Su Kai , Graf Gregory , Vore Mary
Published: April 2010

Lactation is associated with increased expression of bile acid transporters and an increased size and hydrophobicity of the bile acid pool in rats. ATP-binding cassette (ABC) transporters multidrug resistance protein 2 (Mdr2), Abcb11 [bile salt export pump (Bsep)], and Abcg5/Abcg8 heterodimers are essential for the biliary secretion of phospholipids, bile acids, and cholesterol, respectively. We investigated the expression of these transporters and secretion of their substrates in female control and lactating Sprague Dawley rats and C57BL/6 mice. Expression of Abcg5/Abcg8 mRNA was decreased by 97 and 60% by midlactation in rats and mice, respectively; protein levels of Abcg8 were below detection limits in lactating rats. Mdr2 mRNA expression was decreased in lactating rats and mice by 47 and 59%, respectively. Despite these changes in transporter expression, basal concentrations of cholesterol and phospholipid in bile were unchanged in rats and mice, whereas increased Bsep mRNA expression in early lactation coincided with an increased basal biliary bile acid concentration in lactating mice. Following taurocholate infusion, coupling of phospholipid and taurocholate secretion in bile of lactating mice was significantly impaired relative to control mice, with no significant changes in maximal secretion of cholesterol or bile acids. In rats, taurocholate infusion revealed a significantly impaired coupling of cholesterol to taurocholate secretion in bile in lactating vs. control animals. These data reveal marked utilization of an Abcg5/Abcg8-independent mechanism for basal biliary cholesterol secretion in rats during lactation, but a dependence on Abcg5/g8 for maximal biliary cholesterol secretion.
Peripheral mechanisms of thermoregulatory control of skin blood flow in aged humans
Authors: Holowatz Lacy A. , Kenney W. Larry
Published: April 2010

Human skin blood flow is controlled via dual innervation from the sympathetic nervous system. Reflex cutaneous vasoconstriction and vasodilation are both impaired with primary aging, rendering the aged more vulnerable to hypothermia and cardiovascular complications from heat-related illness. Age-related alterations in the thermoregulatory control of skin blood flow occur at multiple points along the efferent arm of the reflex, including 1) diminished sympathetic outflow, 2) altered presynaptic neurotransmitter synthesis, 3) reduced vascular responsiveness, and 4) impairments in downstream (endothelial and vascular smooth muscle) second-messenger signaling. This mechanistic review highlights some of the recent findings in the area of aging and the thermoregulatory control of skin blood flow.
Muscle metaboreflex-induced coronary vasoconstriction functionally limits increases in ventricular contractility
Authors: Coutsos Matthew , Sala-Mercado Javier A. , Ichinose Masashi , Li ZhenHua , Dawe Elizabeth J. , O'Leary Donal S.
Published: April 2010

Muscle metaboreflex activation during dynamic exercise induces a substantial increase in cardiac work and oxygen demand via a significant increase in heart rate, ventricular contractility, and afterload. This increase in cardiac work should cause coronary metabolic vasodilation. However, little if any coronary vasodilation is observed due to concomitant sympathetically induced coronary vasoconstriction. The purpose of the present study is to determine whether the restraint of coronary vasodilation functionally limits increases in left ventricular contractility. Using chronically instrumented, conscious dogs ( n = 9), we measured mean arterial pressure, cardiac output, and circumflex blood flow and calculated coronary vascular conductance, maximal derivative of ventricular pressure (dp/d tmax), and preload recruitable stroke work (PRSW) at rest and during mild exercise (2 mph) before and during activation of the muscle metaboreflex. Experiments were repeated after systemic α1-adrenergic blockade (∼50 μg/kg prazosin). During prazosin administration, we observed significantly greater increases in coronary vascular conductance (0.64 ± 0.06 vs. 0.46 ± 0.03 ml·min−1·mmHg−1; P < 0.05), circumflex blood flow (77.9 ± 6.6 vs. 63.0 ± 4.5 ml/min; P < 0.05), cardiac output (7.38 ± 0.52 vs. 6.02 ± 0.42 l/min; P < 0.05), dP/d tmax(5,449 ± 339 vs. 3,888 ± 243 mmHg/s; P < 0.05), and PRSW (160.1 ± 10.3 vs. 183.8 ± 9.2 erg·103/ml; P < 0.05) with metaboreflex activation vs. those seen in control experiments. We conclude that the sympathetic restraint of coronary vasodilation functionally limits further reflex increases in left ventricular contractility.
Molecular Imaging of N-linked Glycosylation Suggests Glycan Biosynthesis Is a Novel Target for Cancer Therapy
Authors: Contessa Joseph N. , Bhojani Mahaveer S. , Freeze Hudson H. , Ross Brian D. , Rehemtulla Alnawaz , Lawrence Theodore S.
Published: April 2010

Purpose: Redundant receptor tyrosine kinase (RTK) signaling is a mechanism for therapeutic resistance to epidermal growth factor receptor (EGFR) inhibition. A strategy to reduce parallel signaling by coexpressed RTKs is inhibition of N-linked glycosylation (NLG), an endoplasmic reticulum (ER) cotranslational protein modification required for receptor maturation and cell surface expression. We therefore investigated the feasibility of blocking NLG in vivo to reduce overexpression of RTKs.

Experimental Design: We developed a model system to dynamically monitor NLG in vitro and in vivo using bioluminescent imaging techniques. Functional imaging of NLG is accomplished with a luciferase reporter (ER-LucT) modified for endoplasmic reticulum translation and glycosylation. After in vitro validation, this reporter was integrated with D54 glioma xenografts to do noninvasive imaging of tumors, and inhibition of NLG was correlated with RTK protein levels and tumor growth.

Results: The ER-LucT reporter shows the ability to sensitively and specifically detect NLG inhibition. Using this molecular imaging approach we carried out serial imaging studies to determine safe and efficacious in vivo dosing of the GlcNAc-1-phosphotransferase inhibitor tunicamycin, which blocks N-glycan precursor biosynthesis. Molecular analyses of tunicamycin-treated tumors showed reduced levels of EGFR and Met, two RTKs overexpressed in gliomas. Furthermore, D54 and U87MG glioma xenograft tumor experiments showed significant reductions in tumor growth following NLG inhibition and radiation therapy, consistent with an enhancement in tumor radiosensitivity.

Conclusions: This study suggests that NLG inhibition is a novel therapeutic strategy for targeting EGFR and RTK signaling in both gliomas and other malignant tumors. Clin Cancer Res; 16(12); 3205–14. ©2010 AACR.
Single Administration of the CXC Chemokine-Binding Protein Evasin-3 During Ischemia Prevents Myocardial Reperfusion Injury in Mice
Authors: Montecucco Fabrizio , Lenglet Sébastien , Braunersreuther Vincent , Pelli Graziano , Pellieux Corinne , Montessuit Christophe , Lerch René , Deruaz Maud , Proudfoot Amanda E. , Mach François
Published: April 2010

Objective—

Evasins (chemokine-binding proteins) have been shown to selectively neutralize chemokine bioactivity. We investigated the potential benefits of Evasin-3 on mouse myocardial ischemia/reperfusion injury.

Methods and Results—

In vivo and ex vivo (Langendorff model) left coronary artery ligature was performed in C57Bl/6 mice. Coronary occlusion was maintained for 30 minutes, followed by different times (up to 24 hours) of reperfusion. Five minutes after coronary occlusion, mice received 1 intraperitoneal injection of Evasin-3 or vehicle. Infarct size was assessed histologically and by serum cardiac troponin I ELISA. In vitro neutrophil chemotaxis, immunohistology, oxidative stress quantification, real-time RT-PCR analysis of leukocyte chemoattractants, and Western blots for cardioprotective intracellular pathway activation were performed. Evasin-3 reduced infarct size and cardiac troponin I levels compared with vehicle. This effect was associated with the reduction of neutrophil infiltration and reactive oxygen species production within the infarcted myocardium. Evasin-3 did not reduce infarct size in the absence of circulating neutrophils (Langendorff model). Evasin-3 did not influence the activation of intracellular cardioprotective pathways or the expression of leukocyte chemoattractants during early phases of reperfusion.

Conclusion—

Single administration of Evasin-3 during myocardial ischemia significantly reduced infarct size by preventing CXC chemokine-induced neutrophil recruitment and reactive oxygen species production in myocardial ischemia/reperfusion.
Cell Death–Mediated Cleavage of the Attraction Signal p43 in Human Atherosclerosis
Authors: Martinet Wim , De Meyer Inge , Cools Nathalie , Timmerman Vincent , Bult Hidde , Bosmans Johan , De Meyer Guido R.Y.
Published: April 2010

Objective—

Apoptosis is a key feature of advanced atherosclerotic plaques. Attraction signals such as p43 released from apoptotic cells play a crucial role in the timely removal of the apoptotic remnants by recruiting fresh phagocytes. Here, we sought to determine whether p43 may link apoptosis to inflammation and plaque progression.

Methods and Results—

RT-PCR and immunohistochemistry showed that p43 was abundantly expressed in human plaques compared with nonatherosclerotic mammary arteries and colocalized with splicing factor SC-35. Cell culture experiments indicated that p43 expression was associated with enhanced protein translation. On initiation of apoptosis or necrosis, p43 was cleaved by calpains and released as truncated protein p43(apoptosis-released factor [ARF]). Processing of p43 into endothelial monocyte activating polypeptide II was not observed. Full-length p43, but not p43(ARF) or endothelial monocyte activating polypeptide II, activated THP1 monocytes (upregulation of tumor necrosis factor α, interleukin 1β, interleukin 8, macrophage inflammatory protein (MIP)-1α, MIP1β, MIP2α) and endothelial cells (enhanced synthesis of E-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, tissue factor). The chemotactic activity of p43 or fragments thereof was poor compared with ATP. Treatment of smooth muscle cells with p43 did not induce cell death.

Conclusion—

p43 is cleaved during apoptosis by calpains and released as a truncated protein that is harmless for the structure of the plaque.
Sex Differences in the Phosphorylation of Mitochondrial Proteins Result in Reduced Production of Reactive Oxygen Species and Cardioprotection in Females
Authors: Lagranha Claudia J. , Deschamps Anne , Aponte Angel , Steenbergen Charles , Murphy Elizabeth
Published: April 2010

Rationale
:

Although premenopausal females have a lower risk for cardiovascular disease, the mechanism(s) are poorly understood.

Objective
:

We tested the hypothesis that cardioprotection in females is mediated by altered mitochondrial protein levels and/or posttranslational modifications.

Methods and Results
:

Using both an in vivo and an isolated heart model of ischemia and reperfusion (I/R), we found that females had less injury than males. Using proteomic methods we found that female hearts had increased phosphorylation and activity of aldehyde dehydrogenase (ALDH)2, an enzyme that detoxifies reactive oxygen species (ROS)-generated aldehyde adducts, and that an activator of ALDH2 reduced I/R injury in males but had no significant effect in females. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, blocked the protection and the increased phosphorylation of ALDH2 in females, but had no effect in males. Furthermore, we found an increase in phosphorylation of α-ketoglutarate dehydrogenase (αKGDH) in female hearts. αKGDH is a major source of ROS generation particularly with a high NADH/NAD ratio which occurs during I/R. We found decreased ROS generation in permeabilized female mitochondria given αKGDH substrates and NADH, suggesting that increased phosphorylation of αKGDH might reduce ROS generation by αKGDH. In support of this hypothesis, we found that protein kinase C–dependent phosphorylation of purified αKGDH reduced ROS generation. Additionally, myocytes from female hearts had less ROS generation following I/R than males and addition of wortmannin increased ROS generation in females to the same levels as in males.

Conclusions
:

These data suggest that posttranslational modifications can modify ROS handling and play an important role in female cardioprotection.
Role of Afadin in Vascular Endothelial Growth Factor– and Sphingosine 1-Phosphate–Induced Angiogenesis
Authors: Tawa Hideto , Rikitake Yoshiyuki , Takahashi Motonori , Amano Hisayuki , Miyata Muneaki , Satomi-Kobayashi Seimi , Kinugasa Mitsuo , Nagamatsu Yuichi , Majima Takashi , Ogita Hisakazu , Miyoshi Jun , Hirata Ken-ichi , Takai Yoshimi
Published: April 2010

Rationale
:

Angiogenesis contributes to physiological and pathological conditions, including atherosclerosis. The Rap1 small G protein regulates vascular integrity and angiogenesis. However, little is known about the effectors of Rap1 involved in angiogenesis. It is not known whether afadin, an adherens junction protein that connects immunoglobulin-like adhesion molecule nectins to the actin cytoskeleton and binds activated Rap1, plays a role in angiogenesis.

Objective
:

We investigated the role of endothelial afadin in angiogenesis and attempted to clarify the underlying molecular mechanism.

Methods and Results
:

Treatment of human umbilical vein endothelial cells (HUVECs) with vascular endothelial growth factor (VEGF) and sphingosine 1-phosphate (S1P) induced the activation of Rap1. Activated Rap1 regulated intracellular localization of afadin. Knockdown of Rap1 or afadin by small interfering RNA inhibited the VEGF- and S1P-induced capillary-like network formation, migration, and proliferation, and increased the serum deprivation-induced apoptosis of HUVECs. Knockdown of Rap1 or afadin decreased the accumulation of adherens and tight junction proteins to the cell–cell contact sites. Rap1 regulated the interaction between afadin and phosphatidylinositol 3-kinase (PI3K), recruitment of the afadin–PI3K complex to the leading edge, and the activation of Akt, indicating the involvement of Rap1 and afadin in the PI3K–Akt signaling pathway. Binding of afadin to Rap1 regulated the activity of Rap1 in a positive-feedback manner. In vivo, conditional deletion of afadin in mouse vascular endothelium using a Cre-loxP system impaired the VEGF- and S1P-induced angiogenesis.

Conclusions
:

These results demonstrate a novel molecular mechanism by which Rap1 and afadin regulate the VEGF- and S1P-induced angiogenesis.
Efficacy of Homocysteine-Lowering Therapy With Folic Acid in Stroke Prevention
Authors: Lee Meng , Hong Keun-Sik , Chang Shen-Chih , Saver Jeffrey L.
Published: April 2010

Background and Purpose—

Although a lower serum homocysteine concentration is associated with a reduced risk of stroke in epidemiologic studies, randomized, controlled trials have yielded mixed findings regarding the effect of therapeutic homocysteine lowering on stroke prevention. We performed a meta-analysis of randomized, controlled trials to assess the efficacy of folic acid supplementation in the prevention of stroke.

Methods—

Salient trials were identified by formal literature search. Relative risk (RR) with 95% CI was used as a measure of the association between folic acid supplementation and risk of stroke, after pooling data across trials in a fixed-effects model.

Results—

The search identified 13 randomized, controlled trials that had enrolled 39 005 participants for folic acid therapy to reduce homocysteine in which stroke was reported as an outcome measure. Across all trials, folic acid supplementation was associated with a trend toward mild benefit that did not reach statistical significance in reducing the risk of stroke (RR=0.93; 95% CI, 0.85–1.03;
P
=0.16). The RR for nonsecondary prevention trials was 0.89 (95% CI, 0.79–0.99;
P
=0.03). In stratified analyses, a greater beneficial effect was seen in the trials testing combination therapy of folic acid plus vitamins B6 and B12 (RR=0.83; 95% CI, 0.71–0.97;
P
=0.02) and in the trials that disproportionately enrolled male patients (men:women >2; RR=0.84; 95% CI, 0.74–0.94;
P
=0.003).

Conclusions—

Folic acid supplementation did not demonstrate a major effect in averting stroke. However, potential mild benefits in primary stroke prevention, especially when folate is combined with B vitamins and in male patients, merit further investigation.
Atherosclerotic Plaque Ulceration in the Symptomatic Internal Carotid Artery Is Associated With Nonlacunar Ischemic Stroke
Authors: Homburg Philip J. , Rozie Sietske , van Gils Marjon J. , Jansen Tessa , de Weert Thomas T. , Dippel Diederik W.J. , van der Lugt Aad
Published: April 2010

Background and Purpose—

Atherosclerotic carotid plaque ulceration is considered a marker of previous plaque rupture and subsequent thromboembolism. It can be accurately detected with multidetector CTA. We hypothesized that atherosclerotic plaque ulceration is associated with nonlacunar ischemic stroke rather than lacunar stroke.

Methods—

Prospectively, 750 consecutive patients with transient ischemic attack or ischemic stroke symptoms in the anterior cerebral circulation were evaluated for the presence of atherosclerotic plaque ulceration in the symptomatic carotid artery with multidetector CTA. Patients with stroke attributable to cardiac embolism or other specific etiologies and patients with amaurosis fugax were excluded. Ischemic strokes in the remaining 534 patients were classified as nonlacunar (n=236) or lacunar (n=298) based on clinical symptoms and multidetector CT of the brain. Ulceration was defined as extension of contrast material beyond the vascular lumen into the surrounding plaque.

Results—

Plaque ulceration in the symptomatic carotid artery was more common in nonlacunar strokes (n=47; 20%) as compared to lacunar strokes (n=20; 7%;
P
<0.001). After adjustment for age, gender, cardiovascular risk factors, and degree of stenosis, ulcerations were independently associated with nonlacunar stroke compared to lacunar stroke (odds ratio, 2.70; 95% confidence interval, 1.43–5.09).

Conclusions—

Atherosclerotic carotid plaque ulceration is associated with nonlacunar ischemic stroke, independent of the degree of carotid stenosis. These results suggest that nonlacunar stroke and lacunar stroke are caused by different pathophysiological mechanisms.
Validation of the ABCD
2
Score to Identify the Patients With High Risk of Late Stroke After a Transient Ischemic Attack or Minor Ischemic Stroke
Authors: Yang Jie , Fu Jian-Hui , Chen Xiang-Yan , Chen Yang-Kun , Leung Thomas W. , Mok Vincent , Soo Yannie , Wong Ka-Sing
Published: April 2010

Background and Purpose—

The ABCD
2
score is able to predict the short-term risk of stroke after a transient ischemic attack/minor stroke. We aimed to explore its predictive value for long-term recurrent stroke.

Methods—

Consecutive patients with a transient ischemic attack/minor stroke, hospitalized during a 2-year period, were followed up to document any further stroke and death stratified by a 7-point ABCD
2
score.

Result—

A total of 490 patients were followed for an average of 40.5 months (SD, 10.7 months). Further stroke were identified in 76 (15.5%) patients and 62 (12.7%) patients died during follow-up. Multivariate Cox regression analysis showed that an ABCD
2
score >4 was found to be an independent risk factor for further stroke (hazard ratio, 2.27; 95% CI, 1.36 to 3.80) and for death (hazard ratio, 1.68; 95% CI, 0.99 to 2.85).

Conclusions—

In addition to predicting short-term stroke risk, ABCD
2
score is a useful tool to predict long-term stroke risk after a transient ischemic attack or minor ischemic stroke.
The Physiological Significance of the Time-to-Maximum (Tmax) Parameter in Perfusion MRI
Authors: Calamante Fernando , Christensen Søren , Desmond Patricia M. , Østergaard Leif , Davis Stephen M. , Connelly Alan
Published: April 2010

Background and Purpose—

Many perfusion-related MRI parameters are used to investigate the penumbra in stroke. Although time-to-maximum (Tmax) of the residue function has been suggested as a very promising parameter, its physiological meaning and sensitivity to experimental conditions are not well-understood.

Methods—

We used simulations to further our understanding of the practical meaning of Tmax and to provide recommendations for its use in clinical investigations. We interpret in vivo examples guided by the simulation findings.

Results—

Whereas Tmax has several attractive properties for clinical use, it is shown that its physiological interpretation is complex and affected by experimental conditions. Tmax is found to reflect a combination of delay, dispersion, and, to a lesser degree, mean transit time. It should therefore mainly be considered a measure of macrovascular characteristics. Furthermore, based on the simulations, use of temporal-interpolation is highly recommended, as is correction for slice-acquisition timing differences.

Conclusion—

Special care should be taken when setting-up Tmax thresholds for data acquired with different protocols (eg, multicenter studies) because various factors can influence the measured Tmax. Because of its complementary information, used in conjunction with delay-insensitive cerebral blood-flow, cerebral blood volume, and mean transit time maps, Tmax should provide important additional information on brain hemodynamic status.
One School’s Implementation of RTI With English Language Learners: “Referring Into RTI”
Authors: Orosco Michael John , Klingner Janette
Published: April 2010

The purpose of this study was to determine how a response-to-intervention (RTI) model was implemented with a large percentage of Latino English language learners who were having reading difficulties in an urban elementary school at the primary level (K—2). The authors sought to describe school personnel’s perceptions of RTI, what the model looked like in their school, and the challenges they faced. The authors focused on how teachers’ understandings, beliefs, judgments, professional development, and training affected the RTI decision-making process by investigating classroom-based literacy instruction and problem-solving meetings. This study contributes to the literature by presenting a qualitative, in-depth description of how teachers implemented an RTI model for English language learners. These themes were intertwined and functioned as a negative cycle that created a deficits-based RTI literacy model.
Fiscal Policy Under Labour
Authors: Budd Alan
Published: April 2010

The incoming Labour Government of 1997 promised a new approach to the conduct of fiscal policy. Two lessons to be learnt from previous experience were: (1) adjust for the cycle and build in a margin for uncertainty; (2) set stable fiscal rules and explain clearly fiscal policy. Although the claims for novelty were exaggerated there was a serious attempt to expand the supporting explanatory material at the time of the Budget and the Pre-Budget Report (which was itself an innovation). It started well, with the most significant tightening of fiscal policy occurring in 1997–8; but it ended with a record postwar deficit, a debt/GDP ratio heading for more than 75 per cent of GDP and the suspension of the fiscal rules. While the Treasury was not alone in failing to forecast the financial crisis and its consequences, doubts about the policy were being raised before 2007. Although the fiscal rules were met over the preceding period and projected to be met in future, a succession of current budget deficits and a tendency, from 2001 onwards, for over-optimism in fiscal projections left the UK less well equipped than it might have been to meet the challenges of the crisis.
Differential effects produced by ketamine on oscillatory activity recorded in the rat hippocampus, dorsal striatum and nucleus accumbens
Authors: Hunt Mark J , Falinska Monika , Łęski Szymon , Wójcik Daniel K , Kasicki Stefan
Published: April 2010

Previously, we showed that NMDA antagonists enhance high-frequency oscillations (130–180 Hz) in the nucleus accumbens. However, whether NMDA antagonists can enhance high-frequency oscillations in other brain regions remains unclear. Here, we used monopolar, bipolar and inverse current source density techniques to examine oscillatory activity in the hippocampus, a region known to generate spontaneous ripples (∼200 Hz), its surrounding tissue, and the dorsal striatum, neuroanatomically related to the nucleus accumbens. In monopolar recordings, ketamine-induced increases in the power of high-frequency oscillations were detected in all structures, although the power was always substantially larger in the nucleus accumbens. In bipolar recordings, considered to remove common-mode input, high-frequency oscillations associated with ketamine injection were not present in the regions we investigated outside the nucleus accumbens. In line with this, inverse current source density showed the greatest changes in current to occur in the vicinity of the nucleus accumbens and a monopolar structure of the generator. We found little spatial localisation of ketamine high-frequency oscillations in other areas. In contrast, sharp-wave ripples, which were well localized to the hippocampus, occurred less frequently after ketamine. Notably, we also found ketamine produced small, but significant, changes in the power of 30–90 Hz gamma oscillations (an increase in the hippocampus and a decrease in the nucleus accumbens).
Assessing Self-Efficacy for Safe and Independent Living
Authors: Burnett Jason , Cully Jeffrey A. , Achenbaum W. Andrew , Dyer Carmel Bitondo , Naik Aanand D.
Published: April 2010

In older adults, impaired performance in instrumental activities of daily living (ADL) is associated with vulnerability to harm and diminished capability for safe and independent living. Self-reported measures, despite their limitations, are increasingly used to identify vulnerability in community-living older adults and may not provide accurate evidence of an older adults ability to live safely an independently. A cross-sectional study of 100 older adults with adult protective service substanitated self-neglecting behavior(s), and 100 matched community-living comparisons was conducted to evalaute the association between ADL self-efficacy (ADL-SE) and performance on standardized testing. The Kohlman Evaluation of Living Skills (KELS) and a validated self-report measure of efficacy to perform activities of daily living (ADL) are used. In older adults whose vulnerability presents as self-neglecting behaviors, ADL-SE may not be associated with ADL performance on standardized testing but may still reflect their performance of routine ADL tasks needed for safe and independent living.
Development and Validation of the Personal Strengths Inventory Using Exploratory and Confirmatory Factor Analyses
Authors: Kienfie Liau Albert , Chow Daryl , Teck Kiang Tan  , Senf Konrad
Published: April 2010

The purpose of this study was to establish the reliability and validity of the scores on a brief strengths-based assessment, the 22-item Personal Strengths Inventory (PSI). In Study 1, findings from exploratory factor analysis of 410 adolescents provided evidence for a five-factor solution—social competence (four items), emotional awareness (five items), goal setting (six items), emotional regulation (four items), and empathy (three items). Preliminary evidence of convergent validity was also reported. In Study 2, results from confirmatory factor analysis of 598 adolescents provided additional support for the results obtained from Study 1. Moderate to high reliability coefficients were obtained for the PSI scores. The results are discussed in comparison with other research on social—emotional competence, and further research is suggested.
Psychometric Properties of the Resiliency Scales for Children and Adolescents and Use for Youth With Psychiatric Disorders
Authors: Prince-Embury Sandra
Published: April 2010

This study examines psychometric properties of the Resiliency Scales for Children and Adolescents (RSCA) in two clinical samples: one child sample ( n = 110) and one adolescent sample ( n = 178). The purpose of the study was to examine the distribution characteristics and internal consistency of RSCA scale, subscale, and index scores for youth who were diagnosed with various psychiatric disorders. This article expands on research reported in the RSCA technical manual, which examined small diagnostic groups by combining these groups when examination required larger samples. Findings suggest that the variability, apparent normal distribution, and good to excellent internal consistency of the RSCA global scale and index scores in these two clinical samples support their use to examine dimensions of normal development in clinical samples as well as in normative samples. Suggestions for future research are provided.
Factor Structure of the Devereux Early Childhood Assessment Clinical Form in Low-Income Hispanic American Bilingual Preschool Children
Authors: Oades-Sese Geraldine V. , Kaliski Pamela K. , Weiss Karen
Published: April 2010

The Devereux Early Childhood Assessment Clinical Form (DECA-C) is the first instrument to measure the social-emotional resilience of young children from ages 2 to 5 years. This study is an important step toward gathering validity evidence for the teacher-rated DECA-C. This is the first study to investigate the DECA-C factor structure and the first to examine its use with low-income Hispanic American bilingual preschoolers. The one-factor, three-factor, and higher-order three-factor models were tested for the Total Protective Factors domain and the one-, four-, and higher-order four-factor models for the Total Behavioral Concerns domain. Participants comprised 471 low-income bilingual children of Hispanic backgrounds in an urban public school district in the Northeast. Findings from confirmatory factor analyses indicated that all models tested had poor model fit with this sample; however, future research replicating these findings would be necessary for implementation of modifications. In the meantime, the DECA-C shows promise for use in practice with this particular population. Implications for further research are discussed.
Are Low-Income Canadians Financially Literate? Placing Financial Literacy in the Context of Personal and Structural Constraints
Authors: Buckland Jerry
Published: April 2010

This article argues that financial literacy varies across socioeconomic groups and their neighborhoods, in part because of the adult learning that occurs within a local context. The study begins by explaining that financial literacy needs vary across socioeconomic groups and that there are important structural factors affecting the financial well-being of low-income people. Drawing on data from qualitative field research undertaken in three Canadian inner cities, it then moves to examine low-income respondents’ financial literacy. The results show that many low-income respondents evidenced financial literacy in that many learned to cope with strict budgets, used diversified activities to raise their income, constrained their credit, and were reasonably knowledgeable about relevant government programs and banking services. Where particular constraints were noted in financial literacy, they related to detailed knowledge about institutional policies and attitudes about deeper financial and life goals.
Late-Holocene savanna dynamics in the Amboseli Basin, Kenya
Authors: Rucina Stephen M. , Muiruri Veronica M. , Downton Laura , Marchant Rob
Published: April 2010

Pollen, microscopic charcoal and radiocarbon data are used to document changes in vegetation dynamics during the late Holocene from Namelok Swamp in the Amboseli Basin (Kenya). The data reveal changes in savanna vegetation composition driven by an interaction of climate change, anthropogenic and herbivore activities. The abundance of Celtis, Podocarpus and Syzygium reflects a relatively moist climate from around 3000 to 2400 cal. yr BP. Increased abundance of Acacia, Amaranthaceae/Chenopodiaceae and Poaceae suggest a drier and/or warmer climate from 2150 to around 1675 cal. yr BP. The expansion of Syzygium within the catchment and decrease in Amaranthaceae/Chenopodiaceae reflect a relatively wet phase from around 1675 to about 550 cal. yr BP — superimposed on this is a large increase in Poaceae from 1400 to 800 cal. yr BP indicative of a drier environment. The dominance of Amaranthaceae/Chenopodiaceae and Poaceae with an associated decrease in Syzygium from 550 cal. yr BP is thought to correspond to a drier climate. The uppermost samples, dating to the last 150 years, record a large increase in Acacia, Amaranthaceae/Chenopodiaceae and Poaceae with decrease in Syzygium and are attributed to recent land-use changes associated with increased sedentary settlement. The increased presence of Cannabis sativa, Cereal and Ricinus communis pollen, combined with charcoal in the sediment record, particularly from 2500 but more constantly from 1600 cal. yr BP, indicate a long history of human—ecosystem interaction in the Amboseli Basin that has implications for future management of the area.
Early wheat in China: Results from new studies at Donghuishan in the Hexi Corridor
Authors: Flad Rowan , Li Shuicheng  , Wu Xiaohong  , Zhao Zhijun
Published: April 2010

The earliest direct dates of wheat in East Asia come from Donghuishan in Gansu Province, China. Few other dates of wheat in East Asia are direct dates. The previous direct dates at Donghuishan were obtained from wheat without secure context. New samples were taken from a stratigraphic profile at Donghuishan and directly dated. The wheat remains are earlier than any other directly dated wheat east of the Xinjiang Autonomous Region, but considerably later than the previously dated specimen from the same site. These new dates, from the early second millennium BC, are the earliest evidence of significant wheat and barley production and show that the Hexi Corridor played a critical role in the introduction of wheat to China.
Quantifying Lake Athabasca (Canada) water level during the ‘Little Ice Age’ highstand from palaeolimnological and geophysical analyses of a transgressive barrier-beach complex
Authors: Johnston John W. , Köster Dörte , Wolfe Brent B. , Hall Roland I. , Edwards Thomas W.D. , Endres Anthony L. , Martin Margaret E. , Wiklund Johan A. , Light Caleb
Published: April 2010

We combine multiproxy palaeolimnological and geophysical analyses of a barrier-beach complex to estimate the water level of a sustained Lake Athabasca (Canada) highstand during the ‘Little Ice Age’ (LIA; 1600—1900 CE). Palaeolimnological analyses on sediment cores from the lagoon behind the barrier indicate high water levels during the LIA, controlled by subsurface hydrological connection with Lake Athabasca. Key features in the LIA stratigraphic interval are sand laminations deposited by overwash events and low C/N ratios reflecting deposition of predominantly aquatic organic matter. Ground penetrating radar profiles of the barrier reveal a depositional transgression sequence composed of waterlain landward-dipping foreset beds and horizontal topset beds, overlain by aeolian deposits. Stratigraphic relations suggest that the LIA washover deposits in the lagoon formed as the barrier was actively translating landward, and were generated by high-water events on Lake Athabasca that overtopped the barrier. This indicates Lake Athabasca rose to at least the elevation defined by the contact between the waterlain and aeolian sediments in the barrier, which is >4 m above the historical daily average from gauged records available since 1930 and likely represents storm events during the highstand. Assuming a similar relation between daily average and maximum lake level as in the historical gauge record, our findings suggest that Lake Athabasca was on average 2.3 m higher during the LIA than present day. Extrapolation of this high-water plane into the adjacent Peace-Athabasca Delta indicates that 70% of the modern landscape was frequently and perennially flooded until very recently, consistent with palaeolimnological evidence from several lakes in the delta.
Protective effects of melatonin and Glycyrrhiza glabra extract on ochratoxin A—induced damages on testes in mature rats
Authors: Malekinejad Hassan , Mirzakhani Navideh , Razi Mazdak , Cheraghi Hadi , Alizadeh Arash , Dardmeh Fereshteh
Published: April 2010

The effect of Glycyrrhiza glabra extract (GgE) as a natural antioxidant and melatonin (MEL) on ochratoxin A (OTA)-induced histopathological damages on the testes and oxidative stress was evaluated in male rats. The animals were assigned into four groups (n = 8) including control and test groups. The rats in control group received saline and the animals in the test groups received (200 µg/kg) of OTA, (15 mg/kg) of MEL + (200 µg/kg) OTA and (100 mg/kg) of GgE + (200 µg/kg) OTA, respectively, during 28 consecutive days. The serum total antioxidant power (TAOP) and total thiol molecules (TTM) production were assessed. Moreover, histopathological and histochemical studies were also performed. The results showed that the TAOP and TTM were decreased in OTA-exposed rats, while the animals that received MEL + OTA or GgE + OTA showed an enhancement in the serum TAOP and TTM levels. Histopathological analyses demonstrated that in OTA-exposed rats, the testicular degeneration, seminiferous tubule atrophy, dissociation of germinative epithelium, vasodilatation with vascular thrombosis, perivascular immune cell infiltration, hypertrophied leydic cells, giant cell formation, and negative tubular differentiation index (TDI) were observed. Surprisingly, both the biochemical and histopathological examinations showed that MEL and GgE, albeit with some differences, exerted a protective effect on OTA-induced damages. In conclusion, this data suggest that OTA contamination in animal feeds and human foods could cause reproductive abnormalities. Our data also indicate that OTA, at least partly by interfering in oxidative stress system, exerts its toxic effects on testes whereas MEL and GgE with antioxidant properties could fairly protect rats against OTA toxic effects.