bluuebunny/crossref_metadata_2025 huggingface dataset:
Chronic Fine Particulate Matter Exposure Induces Systemic Vascular Dysfunction via NADPH Oxidase and TLR4 Pathways
Authors: Kampfrath Thomas , Maiseyeu Andrei , Ying Zhekang , Shah Zubair , Deiuliis Jeffrey A. , Xu Xiaohua , Kherada Nisharahmed , Brook Robert D. , Reddy Kongara M. , Padture Nitin P. , Parthasarathy Sampath , Chen Lung Chi , Moffatt-Bruce Susan , Sun Qinghua , Morawietz Henning , Rajagopalan Sanjay
Published: January 2011

Rationale:

Chronic exposure to ambient air-borne particulate matter of <2.5 μm (PM
2.5
) increases cardiovascular risk. The mechanisms by which inhaled ambient particles are sensed and how these effects are systemically transduced remain elusive.

Objective:

To investigate the molecular mechanisms by which PM
2.5
mediates inflammatory responses in a mouse model of chronic exposure.

Methods and Results:

Here, we show that chronic exposure to ambient PM
2.5
promotes Ly6C
high
inflammatory monocyte egress from bone-marrow and mediates their entry into tissue niches where they generate reactive oxygen species via NADPH oxidase. Toll-like receptor (TLR)4 and Nox2 (gp91
phox
) deficiency prevented monocyte NADPH oxidase activation in response to PM
2.5
and was associated with restoration of systemic vascular dysfunction. TLR4 activation appeared to be a prerequisite for NAPDH oxidase activation as evidenced by reduced p47
phox
phosphorylation in TLR4 deficient animals. PM
2.5
exposure markedly increased oxidized phospholipid derivatives of 1-palmitoyl-2-arachidonyl-
sn
-glycero-3-phosphorylcholine (oxPAPC) in bronchioalveolar lavage fluid. Correspondingly, exposure of bone marrow–derived macrophages to oxPAPC but not PAPC recapitulated effects of chronic PM
2.5
exposure, whereas TLR4 deficiency attenuated this response.

Conclusions:

Taken together, our findings suggest that PM
2.5
triggers an increase in oxidized phospholipids in lungs that then mediates a systemic cellular inflammatory response through TLR4/NADPH oxidase–dependent mechanisms.
Nationwide Cohort Study of Risk of Ischemic Heart Disease in Patients With Celiac Disease
Authors: Ludvigsson Jonas F. , James Stefan , Askling Johan , Stenestrand Ulf , Ingelsson Erik
Published: January 2011

Background—

Studies on ischemic heart disease (IHD) incidence in individuals with celiac disease (CD) are contradictory and do not take small intestinal pathology into account.

Methods and Results—

In this Swedish population-based cohort study, we examined the risk of IHD in patients with CD based on small intestinal histopathology. We defined IHD as death or incident disease in myocardial infarction or angina pectoris in Swedish national registers. In 2006 to 2008, we collected duodenal/jejunal biopsy data on CD (equal to villous atrophy; Marsh 3; n=28 190 unique individuals) and inflammation without villous atrophy (Marsh 1 to 2; n=12 598) from all 28 pathology departments in Sweden. A third cohort consisted of 3658 individuals with normal mucosa but positive CD serology (Marsh 0, latent CD). We found an increased risk of incident IHD in patients undergoing small intestinal biopsy that was independent of small intestinal histopathology (CD: hazard ratio [HR], 1.19; 95% confidence interval [CI], 1.11 to 1.28; 991 events; inflammation: HR, 1.28; 95% CI, 1.19 to 1.39; 809 events; and latent CD: HR, 1.14; 95% CI, 0.87 to 1.50; 62 events). Celiac disease (HR, 1.22; 95% CI, 1.06 to 1.40) and inflammation (HR, 1.32; 95% CI, 1.14 to 1.52) were both associated with death resulting from IHD, whereas latent CD was not (HR, 0.71; 95% CI, 0.34 to 1.50).

Conclusions—

Individuals with CD or small intestinal inflammation are at increased risk of incident IHD. We were unable to show a positive association between latent CD and incident IHD.
Inhibition of p38 Mitogen-Activated Protein Kinase Improves Nitric Oxide–Mediated Vasodilatation and Reduces Inflammation in Hypercholesterolemia
Authors: Cheriyan Joseph , Webb Andrew J. , Sarov-Blat Lea , Elkhawad Maysoon , Wallace Sharon M.L. , Mäki-Petäjä Kaisa M. , Collier David J. , Morgan John , Fang Zixing , Willette Robert N. , Lepore John J. , Cockcroft John R. , Sprecher Dennis L. , Wilkinson Ian B.
Published: January 2011

Background—

Oxidized low-density lipoprotein reduces endothelial nitric oxide production (an important mediator of vasoregulation) and activates p38 mitogen-activated protein kinase (MAPK), a mediator of vascular inflammation. Animal models of vascular stress have previously predicted improvements in vascular function after p38 MAPK inhibition. We hypothesized that a selective p38α/β MAPK inhibitor (losmapimod; GW856553) would improve compromised nitric oxide–mediated vasoregulation in patients with hypercholesterolemia.

Methods and Results—

Untreated hypercholesterolemic patients (low-density lipoprotein cholesterol >4.1 mmol/L) were randomized to receive losmapimod 7.5 mg (n=27) or placebo (n=29) twice daily for 28 days. Patients with known vascular disorders (eg, diabetes mellitus, coronary heart disease) were excluded. Forearm blood flow was measured by venous occlusion plethysmography in response to serial intra-arterial infusion of acetylcholine, sodium nitroprusside, and
N
G
-monomethyl-
l
-arginine (L-NMMA). Acetylcholine and L-NMMA responses were significantly impaired (
P
=0.01 and
P
=0.03) compared with responses in control subjects (n=12). In hypercholesterolemic patients treated with losmapimod, responses to acetylcholine were improved by 25% (95% confidence interval, 5 to 48;
P
=0.01), to sodium nitroprusside by 20% (95% confidence interval, 3 to 40;
P
=0.02), and to L-NMMA by 10% (95% confidence interval, −1 to 23;
P
=0.07) compared with placebo. C-reactive protein was reduced by 57% (95% confidence interval, −81 to −6%;
P
<0.05) in patients treated with losmapimod compared with placebo.

Conclusions—

Losmapimod improves nitric oxide–mediated vasodilatation in hypercholesterolemic patients, which is consistent with findings in previous translational animal models. These data support the hypothesis that attenuating the inflammatory milieu by inhibiting p38 MAPK activity improves NO activity. This suggests p38 MAPK as a novel target for patients with cardiovascular disease.

Clinical Trial Registration—

URL:
http://clinicaltrials.gov
. Unique identifier: NCT00474864.
Appropriate Use Criteria For Stress Single-Photon Emission Computed Tomography Sestamibi Studies
Authors: Gibbons Raymond J. , Askew J. Wells , Hodge David , Kaping Beth , Carryer Damita J. , Miller Todd
Published: January 2011

Background—

We previously reported the application of the 2005 American College of Cardiology Foundation appropriate use criteria for stress single-photon emission computed tomography (SPECT) imaging to patients at Mayo Clinic (Rochester, MN) in 2005 and 2006. A subsequent internal quality improvement project focused on physician education in an attempt to reduce the rate of inappropriate SPECT studies.

Methods and Results—

Our 2008 physician education effort, focused on 4 specific indications that accounted for 88% of the inappropriate SPECT studies, included a presentation at medical grand rounds, a publication in the staff newsletter, meetings with physician administrators, and focused presentations to departments/divisions with many ordering physicians. We then remeasured the appropriateness of SPECT studies using previously published methods.

The general categories of study indications, eg, after revascularization, were similar in 273 SPECT patients in 2008 and in our 2005 (n=284) and 2006 (n=284) cohorts. There was a trend suggesting a change in the overall classification of appropriateness over time (
P
=0.08) and a significant change in the rate of inappropriate studies over time (
P
=0.018). Inappropriate studies decreased from 14.4% in 2005 to 7.0% in 2006 before initiation of the quality improvement project. After completion of the quality improvement project, inappropriate studies increased to 11.7% (
P
=0.06). The 95% confidence limits for the 4.7% increase in inappropriate studies after the quality improvement project included a decrease of 0.2% and an increase of 9.6%.

Conclusions—

This quality improvement project, focused on feedback, physician education, and remeasurement, did not reduce the rate of inappropriate stress SPECT studies in a single academic medical center. Similar limited interventions focused on physician education alone may have limited benefit. More extensive intervention may be necessary to improve the quality of care with appropriateness criteria.
Ambulatory Blood Pressure Monitoring in 9357 Subjects From 11 Populations Highlights Missed Opportunities for Cardiovascular Prevention in Women
Authors: Boggia José , Thijs Lutgarde , Hansen Tine W. , Li Yan , Kikuya Masahiro , Björklund-Bodegård Kristina , Richart Tom , Ohkubo Takayoshi , Jeppesen Jørgen , Torp-Pedersen Christian , Dolan Eamon , Kuznetsova Tatiana , Olszanecka Agnieszka , Tikhonoff Valérie , Malyutina Sofia , Casiglia Edoardo , Nikitin Yuri , Lind Lars , Maestre Gladys , Sandoya Edgardo , Kawecka-Jaszcz Kalina , Imai Yutaka , Wang Jiguang , Ibsen Hans , O'Brien Eoin , Staessen Jan A.
Published: January 2011

To analyze sex-specific relative and absolute risks associated with blood pressure (BP), we performed conventional and 24-hour ambulatory BP measurements in 9357 subjects (mean age, 52.8 years; 47% women) recruited from 11 populations. We computed standardized multivariable-adjusted hazard ratios for associations between outcome and systolic BP. During a course of 11.2 years (median), 1245 participants died, 472 of cardiovascular causes. The number of fatal combined with nonfatal events was 1080, 525, and 458 for cardiovascular and cardiac events and for stroke, respectively. In women and men alike, systolic BP predicted outcome, irrespective of the type of BP measurement. Women compared with men were at lower risk (hazard ratios for death and all cardiovascular events=0.66 and 0.62, respectively;
P
<0.001). However, the relation of all cardiovascular events with 24-hour BP (
P
=0.020) and the relations of total mortality (
P
=0.023) and all cardiovascular (
P
=0.0013), cerebrovascular (
P
=0.045), and cardiac (
P
=0.034) events with nighttime BP were steeper in women than in men. Consequently, per a 1-SD decrease, the proportion of potentially preventable events was higher in women than in men for all cardiovascular events (35.9% vs 24.2%) in relation to 24-hour systolic BP (1-SD, 13.4 mm Hg) and for all-cause mortality (23.1% vs 12.3%) and cardiovascular (35.1% vs 19.4%), cerebrovascular (38.3% vs 25.9%), and cardiac (31.0% vs 16.0%) events in relation to systolic nighttime BP (1-SD, 14.1 mm Hg). In conclusion, although absolute risks associated with systolic BP were lower in women than men, our results reveal a vast and largely unused potential for cardiovascular prevention by BP-lowering treatment in women.
A Critical Role of Interleukin-10 in Modulating Hypoxia-Induced Preeclampsia-Like Disease in Mice
Authors: Lai Zhongbin , Kalkunte Satyan , Sharma Surendra
Published: January 2011

Hypoxia has been implicated in the pathogenesis of preeclampsia, a hypertensive disorder of pregnancy. However, in vivo evidence and mechanistic understanding remain elusive. Preeclampsia is associated with impaired placental angiogenesis. We have recently shown that interleukin (IL)-10 can support trophoblast-driven endovascular crosstalk. Accordingly, we hypothesize that pathological levels of oxygen coupled with IL-10 deficiency induce severe preeclampsia-like features coupled with elevated production of antiangiogenic factors, apoptotic pathways, and placental injury. Exposure of pregnant wild-type and IL-10
−/−
mice to 9.5% oxygen resulted in graded placental injury and systemic symptoms of renal pathology, proteinuria (wild-type 645.15±115.73 versus 198.09±93.45; IL-10
−/−
819.31±127.85 versus 221.45±82.73 μg/mg/24 hours) and hypertension (wild-type 118.37±14.45 versus 78.67±14.07; IL-10
−/−
136.03±22.59 versus 83.97±18.25 mm Hg). Recombinant IL-10 reversed hypoxia-induced features in pregnant IL-10
−/−
mice confirming the protective role of IL-10 in preeclampsia. Hypoxic exposure caused marked elevation of soluble fms-like tyrosine kinase 1 (110.8±20.1 versus 44.7±11.9 ng/mL) in IL-10
−/−
mice compared with their wild-type counterparts (81.6±13.1 versus 41.2±8.9 ng/mL), whereas soluble endoglin was induced to similar levels in both strains (approximately 380±50 versus 180±31 ng/mL). Hypoxia-induced elevation of p53 was associated with marked induction of proapoptotic protein Bax, downregulation of Bcl-2, and trophoblast-specific apoptosis in utero-placental tissue. Collectively, we conclude that severe preeclampsia pathology could be triggered under certain threshold oxygen levels coupled with intrinsic IL-10 deficiency, which lead to excessive activation of antiangiogenic and apoptotic pathways.
Systemic But Not Central Nervous System Nitric Oxide Synthase Inhibition Exacerbates the Hypertensive Effects of Chronic Melanocortin-3/4 Receptor Activation
Authors: do Carmo Jussara M. , Bassi Mirian , da Silva Alexandre A. , Hall John E.
Published: January 2011

We examined whether systemic or central nervous system (CNS) inhibition of nitric oxide synthase exacerbates the cardiovascular responses of chronic CNS melanocortin 3/4 receptor activation. Sprague-Dawley rats implanted with telemetry probes, venous catheters, and intracerebroventricular (ICV) cannulae were divided in 3 groups. After control measurements, the NO synthase inhibitor L-NAME was infused (10 μg/kg/min intravenous) for 17 days and, starting on day 7 of L-NAME infusion, the melanocortin 3/4 receptor agonist melanotan II (MTII; 10 ng/hr; group 1) or saline vehicle (group 2) was infused ICV for 10 days. A third group not treated with L-NAME also received MTII ICV. Melanocortin 3/4 receptor activation caused a greater increase in mean arterial pressure (MAP) and heart rate in rats treated with intravenous L-NAME (35±6 mm Hg and 56±8 bpm) than L-NAME plus vehicle or MTII alone (22±5 and 9±2 mm Hg, and 26±14 and 27±5 bpm), despite a 58% and 50% reduction in food intake during the first 6 days of MTII infusion. To test if the amplified pressor response to MTII after L-NAME was attributable to a reduction in nitric oxide availability in the brain, we also infused L-NAME directly into the CNS alone or in combination with MTII. ICV infusion of L-NAME plus MTII caused only ≈10 mm Hg increase in MAP with no change in heart rate, similar to the effects of ICV infusion of MTII alone, whereas ICV infusion of L-NAME alone had no effect on MAP. These results suggest that reduction in peripheral, but not CNS, nitric oxide production augments MAP sensitivity to CNS melanocortin 3/4 receptor activation.
Persistent Macrovascular and Microvascular Dysfunction in Patients With Malignant Hypertension
Authors: Shantsila Alena , Dwivedi Girish , Shantsila Eduard , Butt Mehmood , Beevers D. Gareth , Lip Gregory Y.H.
Published: January 2011

Endothelial dysfunction is characteristic of patients with essential hypertension, but only limited data are available on different aspects of endothelial function in patients with malignant-phase hypertension. We investigated myocardial perfusion using real-time quantitative myocardial contrast echocardiography with concurrent assessment of macrovascular and microvascular endothelial damage/dysfunction in patients with previous malignant hypertension (but now in stable phase), who were compared with patients with treated “high-risk” hypertension (hypertension) and healthy controls. We measured flow (hyperemia)-mediated dilation and response to glyceryl trinitrate of brachial artery (ultrasound), microvascular (forearm) response to acetylcholine and sodium nitroprusside (laser Doppler), pulse wave velocity, circulating endothelial and endothelial progenitor cells in 15 patients with malignant hypertension, 40 matched patients with hypertension, and 40 healthy controls. Patients with malignant hypertension had impaired endothelial-dependant response to acetylcholine (
P
<0.001, but not to sodium nitroprusside) compared with hypertension and impaired reaction to both stimuli compared with healthy subjects (
P
<0.001). Patients with malignant hypertension had increased circulating endothelial cells (
P
=0.001), endothelial progenitors (
P
=0.008), and stiffness (
P
=0.003). Both hypertensive groups had impaired response to hyperemia and glyceryl trinitrate when compared with healthy controls (
P
<0.05). Both hypertensive groups had similar myocardial perfusion, which was significantly lower than in healthy controls. There were no significant differences in hyperemia and endothelium-independent stimuli between the 2 hypertensive groups. In conclusion, despite fairly well-controlled blood pressure, malignant hypertension patients had more pronounced abnormalities of macrovascular and microvascular function (which seem to be both endothelium dependent and endothelium independent) compared with patients with hypertension and healthy controls.
Cardiovascular and Sympathetic Effects of Disrupting Tyrosine 985 of the Leptin Receptor
Authors: Harlan Shannon M. , Morgan Donald A. , Dellsperger David J. , Myers Martin G. , Mark Allyn L. , Rahmouni Kamal
Published: January 2011

Leptin acts in the brain to regulate food intake and energy expenditure. Leptin also increases renal sympathetic nerve activity and arterial pressure. The divergent signaling capacities of the leptin receptor (ObRb) mediate the stimulation of various intracellular pathways that are important for leptin control of physiological processes. We evaluated the cardiovascular and sympathetic consequences of disrupting the signal emanating from tyrosine985 of ObRb. For this, we used

Lepr
L985

(
l/l
) mice, which carry a loss of function mutation replacing tyrosine985 of ObRb with leucine. Body weight of
l/l
mice was not significantly different from wild-type controls. In contrast, radiotelemetry measurements revealed that the
l/l
mice had higher arterial pressure and heart rate as compared with controls. Ganglionic blockade caused a greater arterial pressure fall in the
l/l
mice relative to controls. In addition, leptin treatment induced a larger increase in arterial pressure and heart rate in the
l/l
versus wild-type mice. Finally, we compared the response of renal and brown adipose tissue sympathetic nerve activity to intracerebroventricular injection of leptin (2 μg) between
l/l
and control mice. Leptin-induced increase in renal sympathetic nerve activity was greater in
l/l
mice relative to controls. In contrast, the brown adipose tissue sympathetic nerve activity response to leptin was attenuated in the
l/l
mice relative to controls. These data indicate that selective loss of leptin receptor signaling emanating from tyrosine985 enhances the cardiovascular and renal sympathetic effects of leptin. These findings provide important insight into the molecular mechanisms underlying leptin's effects on the sympathetic cardiovascular function and arterial pressure.
Flow-Mediated Dilation and Cardiovascular Event Prediction
Authors: Green Daniel J. , Jones Helen , Thijssen Dick , Cable N.T. , Atkinson Greg
Published: January 2011

Endothelial dysfunction is an early atherosclerotic event that precedes clinical symptoms and may also render established plaque vulnerable to rupture. Noninvasive assessment of endothelial function is commonly undertaken using the flow-mediated dilation (FMD) technique. Some studies indicate that FMD possesses independent prognostic value to predict future cardiovascular events that may exceed that associated with traditional risk factor assessment. It has been assumed that this association is related to the proposal that FMD provides an index of endothelium-derived nitric oxide (NO) function. Interestingly, placement of the occlusion cuff during the FMD procedure alters the shear stress stimulus and NO dependency of the resulting dilation: cuff placement distal to the imaged artery leads to a largely NO-mediated response, whereas proximal cuff placement leads to dilation which is less NO dependent. We used this physiological observation and the knowledge that prognostic studies have used both approaches to examine whether the prognostic capacity of FMD is related to its role as a putative index of NO function. In a meta-analysis of 14 studies (>8300 subjects), we found that FMD derived using a proximal cuff was at least as predictive as that derived using distal cuff placement, despite the latter being more NO dependent. This suggests that, whilst FMD is strongly predictive of future cardiovascular events, this may not solely be related to its assumed NO dependency. Although this finding should be confirmed with more and larger studies, we suggest that any direct measure of vascular (endothelial) function may provide independent prognostic information in humans.
Evolutionary Squeaky Wheel Optimization: A New Framework for Analysis
Authors: Li Jingpeng , Parkes Andrew J. , Burke Edmund K.
Published: January 2011

Squeaky wheel optimization (SWO) is a relatively new metaheuristic that has been shown to be effective for many real-world problems. At each iteration SWO does a complete construction of a solution starting from the empty assignment. Although the construction uses information from previous iterations, the complete rebuilding does mean that SWO is generally effective at diversification but can suffer from a relatively weak intensification. Evolutionary SWO (ESWO) is a recent extension to SWO that is designed to improve the intensification by keeping the good components of solutions and only using SWO to reconstruct other poorer components of the solution. In such algorithms a standard challenge is to understand how the various parameters affect the search process. In order to support the future study of such issues, we propose a formal framework for the analysis of ESWO. The framework is based on Markov chains, and the main novelty arises because ESWO moves through the space of partial assignments. This makes it significantly different from the analyses used in local search (such as simulated annealing) which only move through complete assignments. Generally, the exact details of ESWO will depend on various heuristics; so we focus our approach on a case of ESWO that we call ESWO-II and that has probabilistic as opposed to heuristic selection and construction operators. For ESWO-II, we study a simple problem instance and explicitly compute the stationary distribution probability over the states of the search space. We find interesting properties of the distribution. In particular, we find that the probabilities of states generally, but not always, increase with their fitness. This nonmonotonocity is quite different from the monotonicity expected in algorithms such as simulated annealing.
The Neural Correlates of Object Familiarity and Domain Specificity in the Human Visual Cortex: An fMRI Study
Authors: Zannino Gian Daniele , Barban Francesco , Macaluso Emiliano , Caltagirone Carlo , Carlesimo Giovanni A.
Published: January 2011

Ventral occipito-temporal cortex is known to play a major role in visual object recognition. Still unknown is whether object familiarity and semantic domain are critical factors in its functional organization. Most models assume a functional locus where exemplars of familiar categories are represented: the structural description system. On the assumption that familiarity should modulate the effect of visual noise on form recognition, we attempted to individualize the structural description system by scanning healthy subjects while they looked at familiar (living and nonliving things) and novel 3-D objects, either with increasing or decreasing visual noise. Familiarity modulated the visual noise effect (particularly when familiar items were living things), revealing a substrate for the structural description system in right occipito-temporal cortex. These regions also responded preferentially to living as compared to nonliving items. Overall, these results suggest that living items are particularly reliant on the structural description system.
Alexander of Aphrodisias and his Doctrine of the Soul 1400 Years of Lasting Significance
Authors: Kessler Eckhard
Published: January 2011

This piece of work intends to shed light on Alexander of Aphrodisias from the second-century Aristotle commentator through the history of Aristotelian psychology up to the sixteenth century's clandestine prompter of the new philosophy of nature. In the millennium after his death the head of the Peripatetic school in Athens served as the authority on Aristotle in the Neo-Platonic school, survived the Arabic centuries of philosophy as Averroes' exemplary exponent of the mortality of the soul and as such was not considered worthy of translation by the Latin Scholastics. This attitude changed only in the Late Middle Ages, when the resistance against Averroes grew fierce and Alexander emerged as the only Aristotelian alternative to him. In 1495 his account of Aristotle's psychology was translated and published and the underlying principles of a natural philosophy, based on sense perception and exempt from metaphysics, became accessible. The prompt reception and widespread endorsement of Alexander's teaching testify to his impact throughout the sixteenth century.
TIGGE: Comparison of the Prediction of Southern Hemisphere Extratropical Cyclones by Different Ensemble Prediction Systems
Authors: Froude Lizzie S. R.
Published: January 2011

The prediction of Northern Hemisphere (NH) extratropical cyclones by nine different ensemble prediction systems (EPSs), archived as part of The Observing System Research and Predictability Experiment (THORPEX) Interactive Grand Global Ensemble (TIGGE), has recently been explored using a cyclone-tracking approach. This paper provides a continuation of this work, extending the analysis to the Southern Hemisphere (SH). While the EPSs have larger error in all cyclone properties in the SH, the relative performance of the different EPSs remains broadly consistent between the two hemispheres. Some interesting differences are also shown. The Chinese Meteorological Administration (CMA) EPS has a significantly lower level of performance in the SH compared to the NH. Previous NH results showed that the Centro de Previsão de Tempo e Estudos Climáticos (CPTEC) EPS underpredicts cyclone intensity. The results of this current study show that this bias is significantly larger in the SH. The CPTEC EPS also has very little spread in both hemispheres. As with the NH results, cyclone propagation speed is underpredicted by all the EPSs in the SH. To investigate this further, the bias was also computed for the ECMWF high-resolution deterministic forecast. The bias was significantly smaller than the lower-resolution ECMWF EPS.
Seasonal Variations of Climate Feedbacks in the NCAR CCSM3
Authors: Taylor Patrick C. , Ellingson Robert G. , Cai Ming
Published: January 2011

This study investigates the annual cycle of radiative contributions to global climate feedbacks. A partial radiative perturbation (PRP) technique is used to diagnose monthly radiative perturbations at the top of atmosphere (TOA) due to CO2 forcing; surface temperature response; and water vapor, cloud, lapse rate, and surface albedo feedbacks using NCAR Community Climate System Model, version 3 (CCSM3) output from a Special Report on Emissions Scenarios (SRES) A1B emissions-scenario-forced climate simulation. The seasonal global mean longwave TOA radiative feedback was found to be minimal. However, the global mean shortwave (SW) TOA cloud and surface albedo radiative perturbations exhibit large seasonality. The largest contributions to the negative SW cloud feedback occur during summer in each hemisphere, marking the largest differences with previous results. Results suggest that intermodel spread in climate sensitivity may occur, partially from cloud and surface albedo feedback seasonality differences. Further, links between the climate feedback and surface temperature response seasonality are investigated, showing a strong relationship between the seasonal climate feedback distribution and the seasonal surface temperature response.
The Role of Utility Value in Achievement Behavior: The Importance of Culture
Authors: Shechter Olga G. , Durik Amanda M. , Miyamoto Yuri , Harackiewicz Judith M.
Published: January 2011

Two studies tested how participants’ responses to utility value interventions and subsequent interest in a math technique vary by culture (Westerners vs. East Asians) and levels of initial math interest. Participants in Study 1 were provided with information about the utility value of the technique or not. The manipulation was particularly effective for East Asian learners with initially lower math interest, who showed more interest in the technique relative to low-interest Westerners. Study 2 compared the effects of two types of utility value (proximal or distal) and examined the effects on interest, effort, performance, and process variables. Whereas East Asian participants reaped the most motivational benefits from a distal value manipulation, Westerners benefited the most from a proximal value manipulation. These findings have implications for how to promote motivation for learners with different cultural backgrounds and interests.
Dopamine in nucleus accumbens: salience modulation in latent inhibition and overshadowing
Authors: Nelson AJD , Thur KE , Marsden CA , Cassaday HJ
Published: January 2011

Latent inhibition (LI) is demonstrated when non-reinforced pre-exposure to a to-be-conditioned stimulus retards later learning. Learning is similarly retarded in overshadowing, in this case using the relative intensity of competing cues to manipulate associability. Electrolytic/excitotoxic lesions to shell accumbens (NAc) and systemic amphetamine both reliably abolish LI. Here a conditioned emotional response procedure was used to demonstrate LI and overshadowing and to examine the role of dopamine (DA) within NAc. Experiment 1 showed that LI but not overshadowing was abolished by systemic amphetamine (1.0 mg/kg i.p.). In Experiment 2, 6-hydroxydopamine (6-OHDA) was used to lesion DA terminals within NAc: both shell- and core- (plus shell-)lesioned rats showed normal LI and overshadowing. Experiment 3 compared the effects of amphetamine microinjected at shell and core coordinates prior to conditioning: LI, but not overshadowing, was abolished by 10.0 but not 5.0 µg/side amphetamine injected in core but not shell NAc. These results suggest that the abolition of LI produced by NAc shell lesions is not readily reproduced by regionally restricted DA depletion within NAc; core rather than shell NAc mediates amphetamine-induced abolition of LI; overshadowing is modulated by different neural substrates.
Optimization and learning for rough terrain legged locomotion
Authors: Zucker Matt , Ratliff Nathan , Stolle Martin , Chestnutt Joel , Bagnell J Andrew , Atkeson Christopher G , Kuffner James
Published: January 2011

We present a novel approach to legged locomotion over rough terrain that is thoroughly rooted in optimization. This approach relies on a hierarchy of fast, anytime algorithms to plan a set of footholds, along with the dynamic body motions required to execute them. Components within the planning framework coordinate to exchange plans, cost-to-go estimates, and ‘certificates’ that ensure the output of an abstract high-level planner can be realized by lower layers of the hierarchy. The burden of careful engineering of cost functions to achieve desired performance is substantially mitigated by a simple inverse optimal control technique. Robustness is achieved by real-time re-planning of the full trajectory, augmented by reflexes and feedback control. We demonstrate the successful application of our approach in guiding the LittleDog quadruped robot over a variety of types of rough terrain. Other novel aspects of our past research efforts include a variety of pioneering inverse optimal control techniques as well as a system for planning using arbitrary pre-recorded robot behavior.
Stable dynamic walking over uneven terrain
Authors: Manchester Ian R , Mettin Uwe , Iida Fumiya , Tedrake Russ
Published: January 2011

We propose a constructive control design for stabilization of non-periodic trajectories of underactuated robots. An important example of such a system is an underactuated “dynamic walking” biped robot traversing rough or uneven terrain. The stabilization problem is inherently challenging due to the nonlinearity, open-loop instability, hybrid (impact) dynamics, and target motions which are not known in advance. The proposed technique is to compute a transverse linearization about the desired motion: a linear impulsive system which locally represents “transversal” dynamics about a target trajectory. This system is then exponentially stabilized using a modified receding-horizon control design, providing exponential orbital stability of the target trajectory of the original nonlinear system. The proposed method is experimentally verified using a compass-gait walker: a two-degree-of-freedom biped with hip actuation but pointed stilt-like feet. The technique is, however, very general and can be applied to a wide variety of hybrid nonlinear systems.
Prognostic Markers for Canine Melanocytic Neoplasms
Authors: Smedley R. C. , Spangler W. L. , Esplin D. G. , Kitchell B. E. , Bergman P. J. , Ho H.-Y. , Bergin I. L. , Kiupel M.
Published: January 2011

Many studies have evaluated various prognostic markers for canine melanocytic neoplasms either as primary or secondary goals; however, design, methodology, and statistical validation vary widely across these studies. The goal of this article was to evaluate and compare published canine melanocytic neoplasm studies in relation to the principals established in the Recommended Guidelines for the Conduct and Evaluation of Prognostic Studies in Veterinary Oncology. Based on this evaluation, we determined which parameters currently have the most statistically supported validity for prognostic use in canine melanocytic neoplasia. This information can also be used as part of evidence-based prospective evaluations of treatment regimens. Additionally, we highlight areas in which the current data are incomplete and that warrant further evaluation. This article represents an initiative of the American College of Veterinary Pathologists' Oncology Committee and has been reviewed and endorsed by the World Small Animal Veterinary Association.
Rhabdomyosarcoma in 8 Horses
Authors: Castleman W. L. , Toplon D. E. , Clark C. K. , Heskett T. W. , Farina L. L. , Lynch T. M. , Bryant U. K. , Piero F. Del , Murphy B. , Edwards J. F.
Published: January 2011

This multi-institutional report describes 8 cases of rhabdomyosarcoma in horses. Four neoplasms were in the tongue and other areas of the mouth or head, 2 were in the abdominal wall, and 1 each was in right shoulder muscles and heart. Four rhabdomyosarcomas that were less than 10 cm in diameter were treated by surgical excision or radiation with no recurrence. Two neoplasms greater than 10 cm in diameter in the abdominal wall and the right shoulder were considered inoperable and led to decisions to euthanize the horses. Two neoplasms were incidental findings at necropsy. All the neoplasms were classified as embryonal except for 1 pleomorphic rhabdomyosarcoma. These 8 cases were evaluated with 9 published case reports of equine rhabdomyosarcoma. For all cases, the most common sites were limb muscles (5/17) and tongue (4/17). Metastasis was reported in 4 of the previously published cases; none was found in this study.
The 21st Century Crisis
Authors: Li Minqi
Published: January 2011

Under the current trend, the world is on track towards an extreme greenhouse state that threatens to destroy human civilization and nearly all forms of life on Earth. Without an end to economic growth, it is virtually impossible for meaningful climate stabilization to be achieved. However, both capitalist enterprises and states are constantly driven to expand production and consumption. The climate change crisis is but one of several long-term historical trends that are now leading to the structural crisis of capitalism. The resolution of the crisis and the survival of humanity require the building of a fundamentally different social system.

JEL classification: B51, P16, P20, Q54
Using In-Service and Coaching to Increase Teachers’ Accurate Use of Research-Based Strategies
Authors: Kretlow Allison G. , Cooke Nancy L. , Wood Charles L.
Published: January 2011

Increasing the accurate use of research-based practices in classrooms is a critical issue. Professional development is one of the most practical ways to provide practicing teachers with training related to research-based practices. This study examined the effects of in-service plus follow-up coaching on first grade teachers’ accurate delivery of three research-based strategies during math instruction. Teachers were trained to use a combination of whole-class instruction strategies, including model-lead-test for introducing new concepts and correcting errors, choral responding, and response cards. Results indicated that all teachers improved their delivery of the strategies after the in-service, with a second level of growth achieved after coaching. Improvements also generalized to untrained math sessions. Teachers reported very high levels of satisfaction with the training model.
Nutrition Support for the Acute Lung Injury/Adult Respiratory Distress Syndrome Patient: A Review
Authors: Turner Krista L. , Moore Frederick A. , Martindale Robert
Published: January 2011

Support for Acute Lung Injury (ALI) and Adult Respiratory Distress Syndrome (ARDS) in many ways represents the summation of all intensive care unit nutrition modalities. Basic tenets of management are based on those established for the general population of mechanically ventilated patients. As a marker of critical illness however, patients with ALI/ARDS suffer from other organ dysfunctions that require advanced support. Specific issues to be considered in this population include carbon dioxide production, prevention of aspiration, and modulation of the inflammatory response. These particular areas, with special attention paid to the role of lipids in ALI/ARDS, will be reviewed.
The Holocene climatic evolution of Mediterranean Italy: A review of the continental geological data
Authors: Giraudi C. , Magny M. , Zanchetta G. , Drysdale R.N.
Published: January 2011

We present a synthesis of geological, stratigraphic, geomorphological and stable isotope data collected from continental archives to highlight the environmental and climatic differences between the first and second half of the Holocene of central and southern Italy. The beginning of the Holocene is marked by rapid environmental change. In Mediterranean Italy, between c. 9500 cal. BP and c. 6000—5500 cal. BP, average temperatures were probably higher and environmental conditions were generally stable; between c. 9000 and 7000 cal. BP, meteoric precipitation was at its highest. The end of the wetter period seems to occur later, at c. 6000—5000 cal. BP. Since c. 6000—5000 cal. BP, rapid climatic excursions are apparent in different palaeoclimate proxies, with both variability in meteoric precipitation and temperature evident. Of particular relevance is the event occurring at c. 4200 cal. BP. This event heralds a period of significant environmental change in the Apennines and, more generally, in central Italy. Following this event, environmental variability appears most pronounced and frequent. Some environmental changes during the early Holocene and after 4200 cal. BP seem to be in phase with IRD events in the North Atlantic, which suggest: (1) teleconnections between North Atlantic and Mediterranean areas; and (2) a possible influence of North Atlantic meridional overturning circulation in controlling the advection of moisture over the central Mediterranean basin via westerly air masses. The archives used in this review allow us to consider climate evolution as a driver of most of the observed environmental changes.
Mid-Holocene vegetation history of the central Mediterranean
Authors: Sadori Laura , Jahns S. , Peyron O.
Published: January 2011

This paper provides a synthesis of available palynological data from central Mediterranean lacustrine records, studying the causes of the important vegetation changes which occurred in the mid Holocene. They are illustrated by seven well-dated records, lakes Accesa, Mezzano, Vico, and Pergusa in Italy, Maliq, Voulkaria and Malo J. in the Balkans. A good tool for disentangling climate change and human impact is the combined interpretation of pollen percentage and concentration/influx data. Pollen concentration/influx drops are an indication of increased erosion in the catchment, mainly ascribable to forest reduction. There is no doubt that major synchronous changes could not have been caused by humans alone. Many southern European records show substantial differences between early- and late-Holocene vegetation, suggesting a general evolution from wetter to drier climatic conditions, in agreement with arid phases recognised by other, independent palaeoclimatic methods. Other pollen records show a different trend. The role of changing seasonality seems important for this region of the Mediterranean. Precipitation seasonality increased during the early to mid Holocene with winter precipitation attaining a maximum, and summer precipitation a minimum. At least three rapid climate events with changes in plant biomass are in evidence: an abrupt and short change around 8200 yr BP, another one centred around 6000 yr BP, and one soon after 3000 yr BP. From the beginning of the Bronze Age ( c. 4400 yr BP in this region) human impact overlapped with a climate change, probably bipartite, towards dryness. Our results show that this aridification trend began around 8000 yr BP, and culminated around 4000 yr BP.
Climatic, vegetation and cultural change in the eastern Mediterranean during the mid-Holocene environmental transition
Authors: Roberts Neil , Eastwood Warren J. , Kuzucuoğlu Catherine , Fiorentino Girolamo , Caracuta Valentina
Published: January 2011

The eastern Mediterranean region witnessed changes in human culture of the highest importance between ~9000 and ~2500 cal. BP (7000—500 BC) and over the same time period was affected by very significant shifts in climate. Stable isotope data from lake and deep-sea sediment cores and from cave speleothems show an overall trend from a wetter to a drier climate during the mid Holocene. Superimposed on this trend were multicentennial oscillations in climate, with notable arid phases occurring around 5300—5000 BP, 4500—3900 BP, and 3100—2800 BP (all ages are expressed in calibrated/ calendar years). These phases coincide with major archaeological transitions across the eastern Mediterranean region (Chalcolithic to early Bronze Age, EBA to MBA, and LBA to Iron Age) implying that environmental stress or opportunity may have acted as a pacemaker for cultural change and re-organisation. We use 14C and δ 13C analysis of archaeobotanical samples from two protohistoric sites in Syria to illustrate the linkage between water availability, climate and cultural change during the third and second millennia BC. Specific societal responses to environmental change were not predictable in advance, but resulted instead from contingent processes involving antecedent conditions, human choice and adaptive strategies. Pollen analysis highlights how changes in climate were coupled to increasing human impacts to transform the region’s landscapes. Initial human-induced land-cover transformation commonly took place during Bronze Age times, sometimes coinciding with phases of drier climate, although the pattern and precise timing varied between sites. Changes in climate between the early and late Holocene thus helped to transform eastern Mediterranean landscape ecologies and human cultures, but in complex, non-deterministic ways.
Potential influence of Bond events on mid-Holocene climate and vegetation in southern Pyrenees as assessed from Burg lake LOI and pollen records
Authors: Pèlachs Albert , Julià Ramón , Pérez-Obiol Ramon , Soriano Joan Manuel , Bal Marie-Claude , Cunill Raquel , Catalan Jordi
Published: January 2011

Superimposed on the long-term climate variability attributed to orbital forcing, there are other modes of variability covering timescales from interannual to millennial throughout the Holocene. Their signatures in climate proxy archives can differ substantially because of their lower magnitude and regional diversity. However, if identified they can yield better understanding of the physical mechanisms regionally linking causes and effects. Here we describe a high-resolution record of organic matter accumulation in the sediments of Burg lake (Pyrenees, NE Iberian Peninsula), as assessed using loss on ignition (LOI), and compare it with the ice rafted debris (IRD) indexes from the North Atlantic. The LOI record indicates two main phases in the water body, a lacustrine phase as a shallow lake and a palustrine phase as a fen. The latter covers the period 2600—7200 cal. yr BP and within it there is a high coherence between LOI and IRD, which indicates submillennial climate fluctuations in the Pyrenees that can be related to the North Atlantic influence. The Burg’s LOI record suggests wetter (and occasionally colder) situations in the Pyrenees during high IRD in the Atlantic (Bond oscillations). These fluctuations would likely affect the snow covered period in the mountains (winter and spring seasons) the most, the period in which Atlantic westerlies currently have higher influence on precipitation over the Pyrenees. These climatic oscillations could have favoured Abies penetration during the mid Holocene, as evidenced by increased pollen percentages of this taxon during low IRD values (drier conditions). The pollen record also suggests potential relationships between climate and human activity as early as at mid Holocene, as human-related cereals increase during all the low IRD periods. The human signature (charcoal, cereals) becomes particularly evident at around 2800 cal. yr BP; in this oscillation Pinus overtake Abies in the conifer response to low IRD.
The mid-Holocene climatic transition in the Mediterranean: Causes and consequences
Authors: Roberts N. , Brayshaw D. , Kuzucuoğlu C. , Perez R. , Sadori L.
Published: January 2011

In the Mediterranean there is often no clear time gap separating an early-Holocene period of nature-dominated environmental change from a human-dominated late-Holocene one. This mid-Holocene ‘mélange’ has been the subject of debates that have often been polarised between support for climatic causation and those favouring anthropogenic explanations for changes in vegetation, river flooding, wildfire regimes, etc. One way to shed light on the causes of mid-Holocene landscape changes is to focus on natural archives, such as lake and cave isotopes, the records of which can be unambiguously attributed to climatic forcing. These primary climate proxies can then be compared and contrasted with secondary or response variables, such as pollen and microcharcoal data, which can be the product of either climate changes or human activity or both, ideally using a multiproxy approach. In addition, synthesised primary palaeoclimate data can be compared with regional-scale climate modelling simulations. Both model output and proxy data suggest an east—west division in Mediterranean climate history. They indicate that the eastern Mediterranean experienced an increase in winter-season precipitation during the early Holocene, followed by an oscillatory decline after ~6 ka BP. In western parts of the Mediterranean, early-Holocene changes in precipitation were smaller in magnitude and less coherent spatially, and maximum increases occurred during the mid Holocene, around 6—3 ka BP, before declining to present-day values. Coincident with and partly stimulated by these climatic changes, complex societies developed across the Mediterranean, particularly in eastern parts of the basin during the Bronze Age. In consequence, by the mid-first millennium BC, human-induced land cover conversion, a drier and more variable climate, and changed fire regimes combined to establish typical sclerophyllous vegetation and landscapes in the circum-Mediterranean region.