bluuebunny/crossref_metadata_2025 huggingface dataset:
The Prostaglandin Transporter Regulates Adipogenesis and Aromatase Transcription
Authors: Subbaramaiah Kotha , Hudis Clifford A. , Dannenberg Andrew J.
Published: January 2011

Cytochrome P450 aromatase, encoded by the CYP19 gene, catalyzes estrogen synthesis. In obese postmenopausal women, increased estrogen synthesis in adipose tissue has been linked to hormone-dependent breast carcinogenesis. Hence, it is important to elucidate the mechanisms that regulate CYP19 gene expression. Prostaglandin E2 (PGE2) stimulates the cyclic AMP (cAMP) → protein kinase A (PKA) → cAMP responsive element binding protein (CREB) pathway leading to increased CYP19 transcription. The prostaglandin transporter (PGT) removes PGE2 from the extracellular milieu and delivers it to the cytosol, where it is inactivated. The main objective of this study was to determine whether PGT regulates CYP19 transcription. Silencing of PGT in preadipocytes increased PGE2 levels in the extracellular medium, thereby stimulating the cAMP → PKA pathway resulting in enhanced interaction between pCREB, p300, and the CYP19 I.3/II promoter. A reciprocal decrease in the interaction between the CYP19 I.3/II promoter and BRCA1, a repressor of CYP19 transcription, was observed. Overexpressing PGT reduced extracellular PGE2 levels, suppressed the cAMP → PKA pathway, enhanced the interaction between BRCA1 and p300, and inhibited aromatase expression. We also compared the PGT → aromatase axis in preadipocytes versus adipocytes. Aromatase levels were markedly increased in preadipocytes versus adipocytes. This increase in aromatase was explained, at least in part, by reduced PGT levels leading to enhanced PGE2 → cAMP → PKA signaling. In addition to regulating aromatase expression, PGT-mediated changes in extracellular PGE2 levels were a determinant of adipocyte differentiation. Collectively, these results suggest that PGT modulates adipogenesis and thereby PGE2-mediated activation of the cAMP → PKA → CREB pathway leading to altered CYP19 transcription and aromatase activity. Cancer Prev Res; 4(2); 194–206. ©2011 AACR.
Neural Crest–Derived Stem Cells Migrate and Differentiate Into Cardiomyocytes After Myocardial Infarction
Authors: Tamura Yuichi , Matsumura Keisuke , Sano Motoaki , Tabata Hidenori , Kimura Kensuke , Ieda Masaki , Arai Takahide , Ohno Yohei , Kanazawa Hideaki , Yuasa Shinsuke , Kaneda Ruri , Makino Shinji , Nakajima Kazunori , Okano Hideyuki , Fukuda Keiichi
Published: January 2011

Objective—

We recently demonstrated that primitive neural crest–derived (NC) cells migrate from the cardiac neural crest during embryonic development and remain in the heart as dormant stem cells, with the capacity to differentiate into various cell types, including cardiomyocytes. Here, we examined the migration and differentiation potential of these cells on myocardial infarction (MI).

Methods and Results—

We obtained double-transgenic mice by crossing protein-0 promoter-Cre mice with Floxed–enhanced green fluorescent protein mice, in which the NC cells express enhanced green fluorescent protein. In the neonatal heart, NC stem cells (NCSCs) were localized predominantly in the outflow tract, but they were also distributed in a gradient from base to apex throughout the ventricular myocardium. Time-lapse video analysis revealed that the NCSCs were migratory. Some NCSCs persisted in the adult heart. On MI, NCSCs accumulated at the ischemic border zone area (BZA), which expresses monocyte chemoattractant protein-1 (MCP-1). Ex vivo cell migration assays demonstrated that MCP-1 induced NCSC migration and that this chemotactic effect was significantly depressed by an anti-MCP-1 antibody. Small NC cardiomyocytes first appeared in the BZA 2 weeks post-MI and gradually increased in number thereafter.

Conclusion—

These results suggested that NCSCs migrate into the BZA via MCP-1/CCR2 signaling and contribute to the provision of cardiomyocytes for cardiac regeneration after MI.
Association of Adiponectin, Resistin, and Vascular Inflammation
Authors: Choi Hae Yoon , Kim Sungeun , Yang Sae Jeong , Yoo Hye Jin , Seo Ji A. , Kim Sin Gon , Kim Nan Hee , Baik Sei Hyun , Choi Dong Seop , Choi Kyung Mook
Published: January 2011

Objective—

Adiponectin and resistin are adipokines that are linked to obesity, inflammation, and atherosclerosis.
18
F-Fluorodeoxyglucose (FDG) positron emission tomography is a promising imaging technique that can be used to evaluate vascular inflammation.

Methods and Results—

We measured adiponectin and resistin levels, as well as traditional cardiovascular risk factors, in 60 obese subjects and 60 nonobese controls. In addition, we compared carotid intima-media thickness and target-to-background ratio (TBR) measured using
18
F-fluorodeoxyglucose–positron emission tomography/computed tomography. The mean TBR values were significantly higher in the obese group compared with normal subjects, although their mean carotid intima-media thickness levels were not significantly different. Serum adiponectin levels showed a significant negative correlation with mean TBR values (
r
=−0.215,
P
=0.020), whereas resistin levels were positively correlated with mean TBR values (
r
=0.214,
P
=0.021). Multiple linear regression analysis showed that mean TBR values were independently associated with body mass index, high-sensitivity C-reactive protein, and resistin levels (
R
2
=0.308).

Conclusion—

Adiponectin and resistin may be useful as biomarkers to reflect vascular inflammation. In particular, resistin levels were independently associated with vascular inflammation even after adjusting for other cardiovascular risk factors.
Long-Term Outcome and Impact of Surgery on Adults With Coronary Arteries Originating From the Opposite Coronary Cusp
Authors: Krasuski Richard A. , Magyar Dari , Hart Stephen , Kalahasti Vidyasagar , Lorber Richard , Hobbs Robert , Pettersson Gosta , Blackstone Eugene
Published: January 2011

Background—

An anomalous coronary artery from the opposite sinus of Valsalva may increase sudden death risk in children and young adults, and surgical intervention is often recommended. The impact of this lesion when recognized in the adult and its management are ill defined.

Methods and Results—

We reviewed 210 700 cardiac catheterizations performed over a 35-year period at a single institution and identified 301 adults with an anomalous coronary artery from the opposite sinus of Valsalva, either anomalous right coronary artery from the left cusp or anomalous left main coronary artery from the right cusp. Patients were stratified by the pathway of the anomalous artery and the chosen treatment. Among the 301 patients with anomalous coronary artery from the opposite sinus of Valsalva (0.14% of the cohort), 79% had anomalous right coronary artery from the left cusp, and 18% had an interarterial course (IAC). Patients with IAC were younger (52±13 versus 59±13 years;
P
=0.001) and more likely to undergo surgical intervention (52% versus 27%;
P
<0.001), but mortality was not increased with IAC. Among the 54 patients with IAC, 28 underwent surgical repair with no perioperative deaths. Patients evaluated since 2000 were significantly more likely to be referred for surgery (
P
=0.004). Surgical patients were more likely to have abnormal stress tests (90% versus 43%;
P
=0.01) and had more extensive atherosclerosis but less diabetes mellitus (0% versus 23%;
P
=0.01). Long-term survival at 10 years appeared similar in both groups.

Conclusions—

In this single-center cohort study of patients with an anomalous coronary artery from the opposite sinus of Valsalva, surgical management appears to have been favored recently. Despite no perioperative mortality, a positive impact on long-term survival was not observed. The impact of surgery in older adults with anomalous coronary arteries arising from the opposite coronary sinus with IAC deserves further study.
Microvascular Function Predicts Cardiovascular Events in Primary Prevention
Authors: Anderson Todd J. , Charbonneau Francois , Title Lawrence M. , Buithieu Jean , Rose M. Sarah , Conradson Heather , Hildebrand Kathy , Fung Marinda , Verma Subodh , Lonn Eva M.
Published: January 2011

Background—

Biomarkers of atherosclerosis may refine clinical decision making in individuals at risk of cardiovascular disease. The purpose of the study was to determine the prognostic significance of endothelial function and other vascular markers in apparently healthy men.

Methods and Results—

The cohort consisted of 1574 men (age, 49.4 years) free of vascular disease. Measurements included flow-mediated dilation and its microvascular stimulus, hyperemic velocity, carotid intima-media thickness, and C-reactive protein. Cox proportional hazard models evaluated the relationship between vascular markers, Framingham risk score, and time to a first composite cardiovascular end point of vascular death, revascularization, myocardial infarction, angina, and stroke. Subjects had low median Framingham risk score (7.9%). Cardiovascular events occurred in 71 subjects (111 events) over a mean follow-up of 7.2±1.7 years. Flow-mediated dilation was not associated with subsequent cardiovascular events (hazard ratio, 0.92;
P
=0.54). Both hyperemic velocity (hazard ratio, 0.70; 95% confidence interval, 0.54 to 0.90;
P
=0.006) and carotid intima-media thickness (hazard ratio, 1.45; confidence interval, 1.15 to 1.83;
P
=0.002) but not C-reactive protein (
P
=0.35) were related to events in a multivariable analysis that included Framingham risk score (per unit SD). Furthermore, the addition of hyperemic velocity to Framingham risk score resulted in a net clinical reclassification improvement of 28.7% (
P
<0.001) after 5 years of follow-up in the intermediate-risk group. Overall net reclassification improvement for hyperemic velocity was 6.9% (
P
=0.24).

Conclusions—

In men, hyperemic velocity, the stimulus for flow-mediated dilation, but not flow-mediated dilation itself was a significant risk marker for adverse cardiovascular outcomes. The prognostic value was additive to traditional risk factors and carotid intima-media thickness. Hyperemic velocity, a newly described marker of microvascular function, is a novel tool that may improve risk stratification of lower-risk healthy men.
Mechanisms of Atrial Tachyarrhythmias Associated With Coronary Artery Occlusion in a Chronic Canine Model
Authors: Nishida Kunihiro , Qi Xiao Yan , Wakili Reza , Comtois Philippe , Chartier Denis , Harada Masahide , Iwasaki Yu-ki , Romeo Philippe , Maguy Ange , Dobrev Dobromir , Michael Georghia , Talajic Mario , Nattel Stanley
Published: January 2011

Background—

Coronary artery disease predisposes to atrial fibrillation (AF), but the effects of chronic atrial ischemia/infarction on AF-related substrates are unknown.

Methods and Results—

Regional right atrial myocardial infarction (MI) was created in 40 dogs by ligating an artery that supplies the right atrial free wall and not the ventricles; 35 sham dogs with the same artery isolated but not ligated were controls. Dogs were observed 8 days after MI and subjected to open-chest study, in vitro optical mapping, and/or cell isolation for patch-clamp and Ca
2+
imaging on day 8. Holter ECGs showed more spontaneous atrial ectopy in MI dogs (eg, 662±281 on day 7 versus 34±25 ectopic complexes per day at baseline; 52±21 versus 1±1 atrial tachycardia episodes per day). Triggered activity was increased in MI border zone cells, which had faster decay of caffeine-evoked Ca
2+
transients and enhanced (by ≈73%) Na
+
-Ca
2+
exchange current. Spontaneous Ca
2+
sparks (confocal microscopy) occurred under β-adrenergic stimulation in more MI dog cells (66±9%) than in control cells (29±4%;
P
<0.01). Burst pacing induced long-lasting AF in MI dogs (1146±259 versus 30±14 seconds in shams). Increased border zone conduction heterogeneity was confirmed by both bipolar electrode mapping in vivo and optical mapping. Optical mapping demonstrated stable border zone reentry in all 9 MI preparations but in none of 6 shams. Border zone tissue showed increased fibrous tissue content.

Conclusions—

Chronic atrial ischemia/infarction creates substrates for both spontaneous ectopy (Ca
2+
-release events, increased Na
+
-Ca
2+
exchange current) and sustained reentry (conduction abnormalities that anchor reentry). Thus, chronic atrial infarction in dogs promotes both AF triggers and the substrate for AF maintenance. These results provide novel insights into potential AF mechanisms in patients with coronary artery disease.
Epidermal Growth Factor Receptor Mediates the Vascular Dysfunction But Not the Remodeling Induced by Aldosterone/Salt
Authors: Griol-Charhbili Violaine , Fassot Céline , Messaoudi Smail , Perret Claudine , Agrapart Vincent , Jaisser Frederic
Published: January 2011

Pathophysiological aldosterone (aldo)/mineralocorticoid receptor signaling has a major impact on the cardiovascular system, resulting in hypertension and vascular remodeling. Mineralocorticoids induce endothelial dysfunction, decreasing vasorelaxation in response to acetylcholine and increasing the response to vasoconstrictors. Activation of the epidermal growth factor receptor (EGFR) is thought to mediate the vascular effects of aldo, but this has yet to be demonstrated in vivo. In this study, we analyzed the molecular and functional vascular consequences of aldo-salt challenge in the waved 2 mouse, a genetic model with a partial loss of EGFR tyrosine kinase activity. Deficient EGFR activity is associated with global oxidative stress and endothelial dysfunction. A decrease in EGFR activity did not affect the arterial wall remodeling process induced by aldo-salt. By contrast, normal EGFR activity was required for the aldo-induced enhancement of phenylephrine- and angiotensin II–mediated vasoconstriction. In conclusion, this in vivo study demonstrates that EGFR plays a key role in aldosterone-mediated vascular reactivity.
Postural Changes in Blood Pressure and Incidence of Ischemic Stroke Subtypes
Authors: Yatsuya Hiroshi , Folsom Aaron R. , Alonso Alvaro , Gottesman Rebecca F. , Rose Kathryn M.
Published: January 2011

The relation of orthostatic blood pressure decrease, or increase, with occurrence of ischemic stroke subtypes has not been examined. We investigated the association of orthostatic blood pressure change (within 2 minutes after supine to standing) obtained at baseline (1987 to 1989) in the Atherosclerosis Risk in Communities Study with incidence of ischemic stroke subtypes through 2007. Among 12 817 black and white individuals without a history of stroke at baseline, 680 ischemic strokes (153 lacunar, 383 nonlacunar thrombotic, and 144 cardioembolic strokes) occurred during a median follow-up of 18.7 years. There was a U-shaped association between orthostatic systolic blood pressure change and lacunar stroke incidence (quadratic
P
=0.004). In contrast, orthostatic systolic blood pressure decrease of 20 mm Hg or more was associated with increased occurrence of nonlacunar thrombotic and cardioembolic strokes independent of sitting systolic blood pressure, antihypertensive medication use, diabetes, and other lifestyle, physiological, biochemical, and medical conditions at baseline (for nonlacunar thrombotic: hazard ratio, 2.02; 95% CI, 1.43 to 2.84; for cardioembolic: hazard ratio, 1.85, 95% CI, 1.01 to 3.39). Orthostatic diastolic blood pressure decrease was associated with increased risk of nonlacunar thrombotic and cardioembolic strokes; the hazard ratios (95% CI) associated with 10 mm Hg lower orthostatic diastolic blood pressure (continuous) were 1.26 (1.06 to 1.50) and 1.41 (1.06 to 1.88), respectively, in fully adjusted models. In conclusion, the present study found that nonlacunar ischemic stroke incidence was positively associated with an orthostatic decrease of systolic and diastolic blood pressure, whereas greater lacunar stroke incidence was associated with both orthostatic increases and decreases in systolic blood pressure.
The Rise of Muslim Foreign Fighters: Islam and the Globalization of Jihad
Authors: Hegghammer Thomas
Published: January 2011

Why has transnational war volunteering increased so dramatically in the Muslim world since 1980? Standard explanations, which emphasize U.S.-Saudi support for the 1980s Afghan mujahideen, the growth of Islamism, or the spread of Wahhabism are insufficient. The increase in transnational war volunteering is better explained as the product of a pan-Islamic identity movement that grew strong in the 1970s Arab world from elite competition among exiled Islamists in international Islamic organizations and Muslim regimes. Seeking political relevance and increased budgets, Hijaz-based international activists propagated an alarmist discourse about external threats to the Muslim nation and established a global network of Islamic charities. This “soft” pan-Islamic discourse and network enabled Arabs invested in the 1980s Afghanistan war to recruit fighters in the name of inter-Muslim solidarity. The Arab-Afghan mobilization in turn produced a foreign fighter movement that still exists today, as a phenomenon partly distinct from al-Qaida. The analysis relies on a new data set on foreign fighter mobilizations, rare sources in Arabic, and interviews with former activists.
Quantifying Differences between 2-m Temperature Observations and Reanalysis Pressure-Level Temperatures in Northwestern North America
Authors: Reuten Christian , Moore R. Dan , Clarke Garry K. C.
Published: January 2011

In northwestern North America, which is a large area with complex physiography, Climatic Research Unit (CRU) Time Series, version 2.1, (TS 2.1) gridded monthly mean 2-m temperatures are systematically lower than interpolated monthly averaged North American Regional Reanalysis (NARR) pressure-level temperatures––in particular, in the winter. Quantification of these differences based on CRU gridded observations can be used to estimate pressure-level temperatures from CRU 2-m temperatures (1901–2002) that predate the NARR period (since 1979). Such twentieth-century pressure-level temperature fields can be used in glacier mass-balance modeling and as an alternative to calibrating general circulation model control runs, avoiding the need for accurate boundary layer parameterization. In this paper, an approach is presented that is transferable to moisture, wind, and other 3D fields with potential applications in wind power generation, ecology, and air quality. At each CRU grid point, the difference between CRU and NARR is regressed against seven predictors in CRU (mean temperature, daily temperature range, precipitation, vapor pressure, cloud cover, and number of wet and frost days) for the period of overlap between CRU and NARR (1979–2002). Bayesian model averaging (BMA) is used to avoid overfitting the CRU–NARR differences and underestimating uncertainties. In cross validations, BMA provides reliable posterior predictions of the CRU–NARR differences and outperforms predictions from three alternative models: the constant model (24-yr mean), the regression model of highest Bayesian model probability, and the full model retaining all seven predictors in CRU.
Impact of Two-Way Aerosol–Cloud Interaction and Changes in Aerosol Size Distribution on Simulated Aerosol-Induced Deep Convective Cloud Sensitivity
Authors: Ekman Annica M. L. , Engström Anders , Söderberg Anders
Published: January 2011

Recent cloud-resolving model studies of single (isolated) deep convective clouds have shown contradicting results regarding the response of the deep convection to changes in the aerosol concentration. In the present study, a cloud-resolving model including explicit aerosol physics and chemistry is used to examine how the complexity of the aerosol model, the size of the aerosols, and the aerosol activation parameterization influence the aerosol-induced deep convective cloud sensitivity. Six sensitivity series are conducted. A significant difference in the aerosol-induced deep convective cloud sensitivity is found when using different complexities of the aerosol model and different aerosol activation parameterizations. In particular, graupel impaction scavenging of aerosols appears to be a crucial process because it efficiently may limit the number of cloud condensation nuclei (CCN) at a critical stage of cloud development and thereby dampen the convection. For the simulated case, a 100% increase in aerosol concentration results in a difference in average updraft between the various sensitivity series that is as large as the average updraft increase itself. The change in graupel and rain formation also differs significantly. The sign of the change in precipitation is not always directly proportional to the change in updraft velocity and several of the sensitivity series display a decrease of the rain amount with increasing updraft velocity. This result illustrates the need to account for changes in evaporation processes and subsequent cooling when assessing aerosol effects on deep convective strength. The model simulations also show that an increased number of aerosols in the Aitken mode (here defined by 23 ≤ d ≤ 100.0 nm) results in a larger impact on the convective strength compared to an increased number of aerosols in the accumulation mode (here defined by 100 ≤ d ≤ 900.0 nm). When accumulation mode aerosols are activated and grow at the beginning of the cloud cycle, the supersaturation near the cloud base is lowered, which to some extent limits further aerosol activation. The simulations indicate a need to better understand and represent the two-way interaction between aerosols and clouds when studying aerosol-induced deep convective cloud sensitivity.
Instability of Shielded Surface Temperature Vortices
Authors: Harvey Benjamin J. , Ambaum Maarten H. P. , Carton Xavier J.
Published: January 2011

The stability characteristics of the surface quasigeostrophic shielded Rankine vortex are found using a linearized contour dynamics model. Both the normal modes and nonmodal evolution of the system are analyzed and the results are compared with two previous studies. One is a numerical study of the instability of smooth surface quasigeostrophic vortices with which qualitative similarities are found and the other is a corresponding study for the two-dimensional Euler system with which several notable differences are highlighted.
Regional Impacts of Climate Change and Atmospheric CO2 on Future Ocean Carbon Uptake: A Multimodel Linear Feedback Analysis
Authors: Roy Tilla , Bopp Laurent , Gehlen Marion , Schneider Birgit , Cadule Patricia , Frölicher Thomas L. , Segschneider Joachim , Tjiputra Jerry , Heinze Christoph , Joos Fortunat
Published: January 2011

The increase in atmospheric CO2 over this century depends on the evolution of the oceanic air–sea CO2 uptake, which will be driven by the combined response to rising atmospheric CO2 itself and climate change. Here, the future oceanic CO2 uptake is simulated using an ensemble of coupled climate–carbon cycle models. The models are driven by CO2 emissions from historical data and the Special Report on Emissions Scenarios (SRES) A2 high-emission scenario. A linear feedback analysis successfully separates the regional future (2010–2100) oceanic CO2 uptake into a CO2-induced component, due to rising atmospheric CO2 concentrations, and a climate-induced component, due to global warming. The models capture the observation-based magnitude and distribution of anthropogenic CO2 uptake. The distributions of the climate-induced component are broadly consistent between the models, with reduced CO2 uptake in the subpolar Southern Ocean and the equatorial regions, owing to decreased CO2 solubility; and reduced CO2 uptake in the midlatitudes, owing to decreased CO2 solubility and increased vertical stratification. The magnitude of the climate-induced component is sensitive to local warming in the southern extratropics, to large freshwater fluxes in the extratropical North Atlantic Ocean, and to small changes in the CO2 solubility in the equatorial regions. In key anthropogenic CO2 uptake regions, the climate-induced component offsets the CO2-induced component at a constant proportion up until the end of this century. This amounts to approximately 50% in the northern extratropics and 25% in the southern extratropics and equatorial regions. Consequently, the detection of climate change impacts on anthropogenic CO2 uptake may be difficult without monitoring additional tracers, such as oxygen.
The Moisture Budget of the Polar Atmosphere in MERRA
Authors: Cullather Richard I. , Bosilovich Michael G.
Published: January 2011

The atmospheric moisture budget from the Modern Era Retrospective-Analysis for Research and Applications (MERRA) is evaluated in polar regions for the period 1979–2005 and compared with previous estimates, accumulation syntheses over polar ice sheets, and in situ Arctic precipitation observations. The system is based on a nonspectral background model and utilizes the incremental analysis update scheme. The annual moisture convergence from MERRA for the north polar cap is comparable to previous estimates using 40-yr European Centre for Medium-Range Weather Forecasts Re-Analysis (ERA-40) and earlier reanalyses but it is more than 50% larger than MERRA precipitation minus evaporation (P − E) computed from physics output fields. This imbalance is comparable to earlier reanalyses for the Arctic. For the south polar cap, the imbalance is 20%. The MERRA physics output fields are also found to be overly sensitive to changes in the satellite observing system, particularly over data-sparse regions of the Southern Ocean. Comparisons between MERRA and prognostic fields from two contemporary reanalyses yield a spread of values from 6% of the mean over the Antarctic Ice Sheet to 61% over a domain of the Arctic Ocean. These issues highlight continued problems associated with the representation of cold-climate physical processes in global data assimilation models. The distribution of MERRA surface fluxes over the major polar ice sheets emphasizes larger values along the coastal escarpments, which agrees more closely with recent assessments of ice sheet accumulation using regional models. Differences between these results and earlier assessments illustrate a continued ambiguity in the surface moisture flux distribution over Greenland and Antarctica. The higher spatial and temporal resolution as well as the availability of all budget components, including analysis increments in MERRA, offer prospects for an improved representation of the high-latitude water cycle in reanalyses.
Characteristics of Land–Atmosphere Interaction Parameters over the Tibetan Plateau
Authors: Wang Shuzhou , Ma Yaoming
Published: January 2011

In this study, eddy covariance flux data collected from three research stations on the Tibetan Plateau—Qomolangma for Atmospheric and Environmental Observation and Research, Nam Co for Multisphere Observation and Research, and Southeast Tibet Station for Alpine Environment Observation and Research, Chinese Academy of Sciences—are used to analyze the variation of momentum transfer coefficient (CD), heat transfer coefficient (CH), aerodynamic roughness length (z0m), thermal roughness length (z0h), and excess resistance to heat transfer (kB−1, where k is von Kármán’s constant and B−1 is a non-dimensional bulk parameter). The following results are found. The monthly average surface roughness, bulk transfer coefficient, and excess resistance to heat transfer at all three stations are obtained. The values of average heat bulk transfer coefficients are larger than those of average momentum bulk transfer coefficients at all three stations. The parameter kB−1 exhibits clear diurnal variations with lower values in the night and higher values in the daytime, especially in the afternoon. Negative values of kB−1 are often observed in the night for relatively smooth surfaces on the Tibetan Plateau, indicating that heat transfer efficiency may exceed that of momentum transfer.
On the Geostrophic Adjustment of an Isolated Lens: Dependence on Burger Number and Initial Geometry*
Authors: Stuart Grant A. , Sundermeyer Miles A. , Hebert Dave
Published: January 2011

Geostrophic adjustment of an isolated axisymmetric lens was examined to better understand the dependence of radial displacements and the adjusted velocity on the Burger number and the geometry of initial conditions. The behavior of the adjustment was examined using laboratory experiments and numerical simulations, which were in turn compared to published analytical solutions. Three defining length scales of the initial conditions were used to distinguish between various asymptotic behaviors for large and small Burger numbers: the Rossby radius of deformation, the horizontal length scale of the initial density defect, and the horizontal length scale of the initial pressure gradient. Numerical simulations for the fully nonlinear time-dependent adjustment agreed both qualitatively and quantitatively with analogous analytical solutions. For large Burger numbers, similar agreement was found in laboratory experiments. Results show that a broad range of final states can result from different initial geometries, depending on the values of the relevant length scales and the Burger number computed from initial conditions. For Burger numbers much larger or smaller than unity, differences between different initial geometries can readily exceed an order of magnitude for both displacement and velocity.
Hysteresis and Dynamics of a Western Boundary Current Flowing by a Gap Forced by Impingement of Mesoscale Eddies
Authors: Yuan Dongliang , Wang Zheng
Published: January 2011

Hysteresis of a western boundary current (WBC) flowing by a wide gap of a western boundary and the dynamics of the WBC variations associated with the impingement of mesoscale eddies from the eastern side of the gap are studied using a 1.5-layer reduced-gravity quasigeostrophic ocean model. The study focuses on two issues not covered by existing studies: the effects of finite baroclinic deformation radii and time dependence perturbed by mesoscale eddies. The results of the study show that the hysteresis of the WBC of finite baroclinic deformation radii is not controlled by multiple steady-state balances of the quasigeostrophic vorticity equation. Instead, the hysteresis is controlled by the periodic penetrating and the leaping regimes of the vorticity balance. The regime of the vorticity balance inside the gap is dependent on the history of the WBC evolution, which gives rise to the hysteresis of the WBC path. Numerical experiments have shown that the parameter domain of the hysteresis is not sensitive to the baroclinic deformation radius. However, the domain of the periodic solution, which is determined by the lower Hopf bifurcation of the nonlinear system, is found to be sensitive to the magnitude of the baroclinic deformation radius. The lower Hopf bifurcation from steady penetration to periodic penetration is found to occur at lower Reynolds numbers for larger deformation radii. In general, the lower Hopf bifurcation stays outside the hysteresis domain of the Reynolds number. However, for very small deformation radii, the lower Hopf bifurcation falls inside the hysteresis domain, which results in the transition from the leaping to the penetrating regimes of the WBC to skip the periodic regime and hence the disappearance of the upper Hopf bifurcation.

Mesoscale eddies approaching the gap from the eastern basin are found to have significant impact on the WBC path inside the gap when the WBC is at a critical state along the hysteresis loop. Cyclonic (anticyclonic) eddies play the role of reducing (enhancing) the inertial advection of vorticity in the vicinity of the gap so that transitions of the WBC path from the leaping (periodic penetrating) to the periodic penetrating (leaping) regimes are induced. In addition, cyclonic eddies are able to induce transitions of the WBC from the periodic penetrating to the leaping regimes through enhancing the meridional advection by its right fling. The transitions are irreversible because of the nonlinear hysteresis and are found to be sensitive to the strength, size, and approaching path of the eddy.
Shelf Circulation and Cross-Shelf Transport out of a Bay Driven by Eddies from an Open-Ocean Current. Part I: Interaction between a Barotropic Vortex and a Steplike Topography
Authors: Zhang Yu , Pedlosky Joseph , Flierl Glenn R.
Published: January 2011

This paper examines interaction between a barotropic point vortex and a steplike topography with a bay-shaped shelf. The interaction is governed by two mechanisms: propagation of topographic Rossby waves and advection by the forcing vortex. Topographic waves are supported by the potential vorticity (PV) jump across the topography and propagate along the step only in one direction, having higher PV on the right. Near one side boundary of the bay, which is in the wave propagation direction and has a narrow shelf, waves are blocked by the boundary, inducing strong out-of-bay transport in the form of detached crests. The wave–boundary interaction as well as out-of-bay transport is strengthened as the minimum shelf width is decreased. The two control mechanisms are related differently in anticyclone- and cyclone-induced interactions. In anticyclone-induced interactions, the PV front deformations are moved in opposite directions by the point vortex and topographic waves; a topographic cyclone forms out of the balance between the two opposing mechanisms and is advected by the forcing vortex into the deep ocean. In cyclone-induced interactions, the PV front deformations are moved in the same direction by the two mechanisms; a topographic cyclone forms out of the wave–boundary interaction but is confined to the coast. Therefore, anticyclonic vortices are more capable of driving water off the topography. The anticyclone-induced transport is enhanced for smaller vortex–step distance or smaller topography when the vortex advection is relatively strong compared to the wave propagation mechanism.
Tides in a System of Connected Estuaries
Authors: Waterhouse Amy F. , Valle-Levinson Arnoldo , Winant Clinton D.
Published: January 2011

The spatial structure of tidal amplitude and phase in a simplified system of connected estuaries, an idealized version of Florida’s Intracoastal Waterway, is analyzed with a linear analytical model. This model includes friction, the earth’s rotation, and variable bathymetry. It is driven at the connection with the ocean by a co-oscillating tide. Model results compare well with observations of pressure and currents in a section of the Intracoastal Waterway on the east coast of Florida. The comparison suggests that the waterway is highly frictional, causing the amplitude of the water elevation and tidal velocity to decrease away from the inlets to a minimum in the middle of the waterway. The local phase relationship between velocity and water elevation changed nonlinearly from 90° with no friction to 45° with maximum friction. In moderately to highly frictional basins, the phase lag was consistently less than 45°.
The Truncated Geometric Approximation and the Size Distribution of Small Atmospheric Particles
Authors: DeVore J. G.
Published: January 2011

This paper describes a simple relationship between the slope of particulate optical depth as a function of wavelength and the size distribution of spherical particles. It is based on approximating extinction using a truncated geometric optics relationship and is applicable when optical depth decreases with wavelength. The new relationship suggests that extinction versus wavelength measurements are most sensitive to particles that are comparable in size to the wavelength. When optical depth is expressed as a power-law function of wavelength, the resulting particle size distribution is also a power-law function of size, with the two exponents reproducing the well-known relationship between the Ångström and Junge exponents. Examples of applying the new relationship are shown using both numerical calculations based on Mie theory and measurements from the Aerosol Robotic Network (AERONET) sun photometer at NASA Goddard Space Flight Center (GSFC). Since the truncated geometric approximation makes no assumptions per se concerning the form of the particle size distribution, it may find application in supplementing solar aureole profile measurements in retrieving the size distributions of particles in thin clouds—for example, cirrus—or when they are present.
Direct 4D-Var Assimilation of NCEP Stage IV Radar and Gauge Precipitation Data at ECMWF
Authors: Lopez Philippe
Published: January 2011

Direct four-dimensional variational data assimilation (4D-Var) of NCEP stage IV radar and gauge precipitation observations over the eastern United States has been developed and tested in ECMWF’s global Integrated Forecasting System. This is the natural extension of earlier work using a two-step 1D+4D-Var approach. Major aspects of the implementation are described and discussed in this paper. In particular, it is found that assimilating 6-h precipitation accumulations instead of the original hourly data substantially improves the behavior of 4D-Var, especially as regards the validity of the tangent-linear assumption.

The comparison of background and analysis precipitation departures demonstrates that most of the information contained in the new precipitation observations is properly assimilated. Experiments run over the periods April–May and September–October 2009 also show that local precipitation forecasts become significantly better for ranges up to 12 h, which indicates that a genuine precipitation analysis can now be obtained over the eastern United States. Geopotential, temperature, moisture, and wind forecast scores are generally neutral or slightly positive for all regions of the globe and at all ranges, which is consistent with previous 1D+4D-Var results.

The most crucial issue that remains unsolved is the treatment of nonprecipitating model background occurrences because of the corresponding absence of sensitivity in the linearized moist physics. For the moment, only points where both model background and observations are rainy are assimilated. Operational implementation using U.S. data is planned in 2011 and one can hope that new networks of radars (and maybe rain gauges) can be added in the 4D-Var assimilation process in the future.
Evaluation of Surface Analyses and Forecasts with a Multiscale Ensemble Kalman Filter in Regions of Complex Terrain
Authors: Ancell Brian C. , Mass Clifford F. , Hakim Gregory J.
Published: January 2011

Previous research suggests that an ensemble Kalman filter (EnKF) data assimilation and modeling system can produce accurate atmospheric analyses and forecasts at 30–50-km grid spacing. This study examines the ability of a mesoscale EnKF system using multiscale (36/12 km) Weather Research and Forecasting (WRF) model simulations to produce high-resolution, accurate, regional surface analyses, and 6-h forecasts. This study takes place over the complex terrain of the Pacific Northwest, where the small-scale features of the near-surface flow field make the region particularly attractive for testing an EnKF and its flow-dependent background error covariances. A variety of EnKF experiments are performed over a 5-week period to test the impact of decreasing the grid spacing from 36 to 12 km and to evaluate new approaches for dealing with representativeness error, lack of surface background variance, and low-level bias. All verification in this study is performed with independent, unassimilated observations.

Significant surface analysis and 6-h forecast improvements are found when EnKF grid spacing is reduced from 36 to 12 km. Forecast improvements appear to be a consequence of increased resolution during model integration, whereas analysis improvements also benefit from high-resolution ensemble covariances during data assimilation. On the 12-km domain, additional analysis improvements are found by reducing observation error variance in order to address representativeness error. Removing model surface biases prior to assimilation significantly enhances the analysis. Inflating surface wind and temperature background error variance has large impacts on analyses, but only produces small improvements in analysis RMS errors. Both surface and upper-air 6-h forecasts are nearly unchanged in the 12-km experiments. Last, 12-km WRF EnKF surface analyses and 6-h forecasts are shown to generally outperform those of the Global Forecast System (GFS), North American Model (NAM), and the Rapid Update Cycle (RUC) by about 10%–30%, although these improvements do not extend above the surface. Based on these results, future improvements in multiscale EnKF are suggested.
Mechanical and water absorption properties of poly(vinyl alcohol)/sago pith waste biocomposites
Authors: Toh Wen Yee  , Lai Jau Choy  , Wan Aizan Wan Abdul Rahman
Published: January 2011

A series of blends of sago pith waste (SPW) and poly(vinyl alcohol) (PVA) were prepared. Mechanical and water absorption properties of the composites have been investigated. In this study, variable amounts of plasticized SPW (pSPW) and PVA (pPVA) were processed in the presence of glycerol as plasticizers. Composites were compression molded and evaluated. The addition of pSPW reduced the tensile properties of the composites, lowering the elongation and increasing Young’s modulus. The reduction in mechanical strength with the addition of pSPW was a general phenomenon due to the poor interfacial adhesion between the pPVA and Pspw, which can be proved by the scanning electron microscope observations. The percentage of water absorbed of the pPVA/pSPW biocomposites was higher than either the pPVA or pSPW alone while pSPW showed better water resistance compared to pPVA because of the restricted mobility exerted by the cellulose fibers. The incorporation of SPW into PVA decreased both the mechanical and water absorption properties.
Investigating the Relationship Between Antisocial Personality Disorder and Malingering
Authors: Pierson Ashley M. , Rosenfeld Barry , Green Debbie , Belfi Brian
Published: January 2011

Forensic patients with antisocial personality disorder (APD) were compared to forensic patients without APD on a validated measure of malingering (Structured Interview of Reported Symptoms [SIRS]). Results indicated that patients with APD were not significantly more likely to exceed accepted cutoff scores on the SIRS (i.e., 17.9% vs. 11.6%, respectively), nor were they more likely to be suspected of malingering by clinicians (17.9% vs. 18.6%). Although there was a high level of disagreement between clinicians’ determination of malingering and classification by the SIRS, this relationship was not significant. Furthermore, patients with APD who were suspected by clinicians to be malingering were not more likely to be classified as responding genuinely using the SIRS. These findings challenge the recommendation issued by the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text revision) that advises clinicians to be highly suspicious of malingering in the presence of APD.
Construct and Predictive Validity of Criminal Thinking Scales
Authors: Taxman Faye S. , Giuranna Rhodes Anne , Dumenci Levent
Published: January 2011

Tools to assess the concept of criminal thinking have not often been tested in community corrections populations. This article examines the psychometric properties of the Texas Christian University Criminal Thinking Scales (CTS) in a sample of drug-using probationers ( n = 250) participating in a randomized trial. A confirmatory factor analysis found that three of the subscales may not be measuring distinct concepts and that most of the subscales do not distinguish between male and female offenders despite large differences in offending histories in these populations. Concurrent and predictive validity results demonstrated a limited ability of the CTS to correlate with known predictors of recidivism or with follow-up data on criminal activity. The CTS scores did correlate with predictors of treatment processes, including treatment readiness and self-efficacy, indicating that those with higher levels of criminal thinking may be more difficult to engage in treatment and services. Measurement tools of criminal thinking are important to the field, and further work is needed to strengthen the existing tools.
Torture Unveiled
Authors: Haddour Azzedine
Published: January 2011

In recent critical studies, according to Gibson, a sustained and profound critique of Fanon has been launched by feminist and postcolonialist theorists over the past decade, focusing on ‘Algeria Unveiled’. By and large, this critique explores what Fanon calls the ‘historical dynamism of the veil’: the ways in which women strategically donned or removed the veil to subvert French colonialism, and the role women played in the Algerian War. Some theorists criticize Fanon for eulogizing the retrograde tradition of the veil and for ‘normalizing gender inequality’. Others reproach him for his Orientalizing views. A number of critics confuse his pronouncements on the impact of the war which revolutionized the Algerian society and gender relation with the reactionary policies implemented in post-independent Algeria. To fathom the political and ethical concerns raised by Fanon, concerns which such criticism eschews, I propose to read Fanon’s ‘Algeria Unveiled’ in tandem with Bourdieu’s Algeria 1960 against the physical and symbolic violence to which Algerian women were subjected as they were coerced to remove their veil.
Recognizing Historical Injustice through Photography: Mexico 1968
Authors: Noble Andrea
Published: January 2011

This article explores the role of photography in the global work of justice by way of a case study. It focuses on the publication, in December 2001, of a set of photographs by the Mexican newsweekly Proceso, depicting events that occurred in Mexico City on 2 October 1968. Taken at the culmination of a summer of student activism, when the military opened fire on student demonstrators and bystanders, the published photographs showed previously hidden scenes of detention and torture. Locating the publication of these photographs in relation to the historical processes of democratic reform in Mexico, the article aims to contribute to debates regarding the agency of photographic images in the visual politics of humanitarianism, shifting the emphasis away from questions of whether photographs work, to explore instead how they work. In particular, it focuses on the circumstances that authorized the simultaneous entry of the photographs of 1968 into the Mexican and international media spheres, and seeks to illuminate broader questions regarding their specifically photographic mode of address and the intersection between the national settings in which human rights abuses take place and testimonial appeals addressed to a global imagined community.
Fanon and Améry
Authors: Gilroy Paul
Published: January 2011

This article examines the different ways in which torture can be seen to have shaped the political and theoretical outlook of Frantz Fanon and that of his enthusiastic reader, the former Auschwitz prisoner Jean Améry. Building on the latter’s suggestion that torture was the essence of the Third Reich, the reader is asked to apply that insight to an unconventional interpretation of the routinization of torture in contemporary statecraft.
Introduction: Special Section on Recent Photography Theory: The State in Visual Matters
Authors: Bajorek Jennifer
Published: January 2011

This introduction to a special section on ‘Photography and the State’ reflects on trends in photography theory exemplified in essays by Jens Andermann, Ariella Azoulay, Andrea Noble, and Bronwyn Law-Viljoen. It suggests that the contributors make a powerful argument for photography’s emergent contribution to theories of the state and of sovereignty. It situates this work in the context of a growing body of scholarship (by theorists such as Natalia Brizuela, Paula Cortés-Rocca, Clare Harris, Chris Pinney, and Karen Strassler) attuned to photography’s role in political imagination in post-colonial and post-imperial spaces, and underscores movement of the field away from inter-subjective conceptions of photographic ethics and debates about indexicality.