bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPARING EFFECTS OF CLUSTER-COUPLED PATTERNS ON OPINION DYNAMICS
Authors: LIU YUN , SI XIA-MENG , ZHANG YAN-CHAO
Published: May 2012

Community structure is another important feature besides small-world and scale-free property of complex networks. Communities can be coupled through specific fixed links between nodes, or occasional encounter behavior. We introduce a model for opinion evolution with multiple cluster-coupled patterns, in which the interconnectivity denotes the coupled degree of communities by fixed links, and encounter frequency controls the coupled degree of communities by encounter behaviors. Considering the complicated cognitive system of people, the CODA (continuous opinions and discrete actions) update rules are used to mimic how people update their decisions after interacting with someone. It is shown that, large interconnectivity and encounter frequency both can promote consensus, reduce competition between communities and propagate some opinion successfully across the whole population. Encounter frequency is better than interconnectivity at facilitating the consensus of decisions. When the degree of social cohesion is same, small interconnectivity has better effects on lessening the competence between communities than small encounter frequency does, while large encounter frequency can make the greater degree of agreement across the whole populations than large interconnectivity can.
QUASINORMAL MODES AND STABILITY ANALYSIS FOR FOUR-DIMENSIONAL LIFSHITZ BLACK HOLE
Authors: GONZÁLEZ P. A. , SAAVEDRA JOEL , VÁSQUEZ YERKO
Published: May 2012

We study the Lifshitz black hole in four dimensions with dynamical exponent z = 2 and we calculate analytically the quasinormal modes of scalar perturbations. These quasinormal modes allow to study the stability of the Lifshitz black hole and we have obtained that Lifshitz black hole is stable.
SYMMETRY REDUCTION OF BROWNIAN MOTION AND QUANTUM CALOGERO–MOSER MODELS
Authors: HOCHGERNER SIMON
Published: May 2012

Let Q be a Riemannian G-manifold. This paper is concerned with the symmetry reduction of Brownian motion in Q and ramifications thereof in a Hamiltonian context. Specializing to the case of polar actions, we discuss various versions of the stochastic Hamilton–Jacobi equation associated to the symmetry reduction of Brownian motion and observe some similarities to the Schrödinger equation of the quantum–free particle reduction as described by Feher and Pusztai [10]. As an application we use this reduction scheme to derive examples of quantum Calogero–Moser systems from a stochastic setting.
DERIVATIVE FORMULA AND HARNACK INEQUALITY FOR DEGENERATE FUNCTIONAL SDEs
Authors: BAO JIANHAI , WANG FENG-YU , YUAN CHENGGUI
Published: May 2012

By constructing successful couplings, the derivative formula, gradient estimates and Harnack inequalities are established for the semigroup associated with a class of degenerate functional stochastic differential equations.
FIRST PASSAGE TIMES OF REFLECTED GENERALIZED ORNSTEIN–UHLENBECK PROCESSES
Authors: BO LIJUN , REN GUIJUN , WANG YONGJIN , YANG XUEWEI
Published: May 2012

We study first passage problems of a class of reflected generalized Ornstein–Uhlenbeck processes without positive jumps. By establishing an extended Dynkin's formula associated with the process, we derive that the joint Laplace transform of the first passage time and an integral functional stopped at the time satisfies a truncated integro-differential equation. Two solvable examples are presented when the driven Lévy process is a drifted-Brownian motion and a spectrally negative stable process with index α ∈ (1, 2], respectively. Finally, we give two applications in finance.
PERFECT STATE TRANSFER IN XX CHAINS INDUCED BY BOUNDARY MAGNETIC FIELDS
Authors: LINNEWEBER THORBEN , STOLZE JOACHIM , UHRIG GÖTZ S.
Published: May 2012

A recent numerical study of short chains found near-perfect quantum state transfer between the boundary sites of a spin-1/2 XX chain if a sufficiently strong magnetic field acts on these sites. We show that the phenomenon is based on a pair of states strongly localized at the boundaries of the system and provide a simple quantitative analytical explanation.
POPPER'S THOUGHT EXPERIMENT REINVESTIGATED
Authors: RICHARDSON CHRIS D. , DOWLING JONATHAN P.
Published: May 2012

Popper's original thought experiment probed some fundamental and subtle rules of quantum mechanics. He claimed that quantum mechanics was incomplete and devised an experiment to prove it. Two experiments have directly and indirectly tested Popper's hypothesis, and they provide some evidence that Popper's prediction may have been correct. The equations governing these two experiments and Popper's thought experiment will be derived from basic quantum principles. The experimental constants will be inputted and it will show that the two experiments reinforce each other and agree completely with quantum theory.
ON A GENERALIZED QUANTUM SWAP GATE
Authors: WILMOTT COLIN M. , WILD PETER R.
Published: May 2012

The SWAP gate plays a central role in network designs for qubit quantum computation. However, there has been a view to generalize qubit quantum computing to higher dimensional quantum systems. In this paper we construct a generalized SWAP gate using only instances of the generalized controlled-NOT gate to cyclically permute the states of d qudits for d prime.
Rare and problematical bohemograptid graptoloids from the
leintwardinensis
Zone (basal Ludfordian, Silurian) of the northern Howgill Fells, Cumbria
Authors: Rickards R. B.
Published: May 2012

Two new unusually gracile bohemograptid species are recorded from the
leintwardinensis
Zone of the UK, and are assessed as part of the global
Bohemograptus
Proliferation Zone (BPZ). The ‘robust’ form,
B. woodcocki
sp. nov., is a possible ancestor of
Egregiograptus
Rickards & Wright, 1997
; it probably derived indirectly from
Bohemograptus bohemicus tenuis
(
Bouček, 1936
) via
B. bohemicus sensu lato
of
Holland & Palmer (1974)
from the
incipiens
Zone. The more slender form,
B. stonei
sp. nov., is a possible ancestor of
Neolobograptus
Urbanek, 1970
, and probably arose directly from
B. b. tenuis
in the
leintwardinensis
Zone.
Syn-sedimentary deformation of the Ashover Grit (Pennsylvanian, Namurian, Marsdenian Substage) deltaic succession around Wirksworth, Derbyshire, UK
Authors: Chisholm J. I. , Waters C. N.
Published: May 2012

Three sets of syn-sedimentary slides affecting delta deposits of the Ashover Grit have been identified in the area south and east of Wirksworth, Derbyshire, UK. The kilometre-scale slide masses, which are expressed clearly in the landscape, consist of arrays of fault blocks tilted back towards listric fault surfaces that sole out into underlying basinal mudstone. Relationships in one of the slide arrays, at Black Rock, suggest that the movements took place during the later stages of delta advance. There is a possibility that some minor compressional structures exposed in surface sections away from the fault blocks are also related to syndepositional movements.
Stanley Westhead and the Lower Carboniferous (Mississippian) crinoids of the Clitheroe area, Lancashire
Authors: Donovan Stephen K.
Published: May 2012

Stanley Westhead (1910–1986) was a noted collector of fossil crinoids from the Lower Carboniferous of the Clitheroe area, Lancashire. His collection was bequeathed to the Natural History Museum, London. Stanley published little himself, although James Wright (1878–1957) referred to rare specimens in the Westhead Collection in his monograph of the British Carboniferous crinoids. However, Stanley was highly knowledgeable, and his letters were full of observations, comments and ideas on the fossil echinoderms of Clitheroe. He also successfully combated the whims of officialdom, such as stopping the road through Salt Hill Quarry being named after another site.
Phase I Trial of Combretastatin A4 Phosphate (CA4P) in Combination with Bevacizumab in Patients with Advanced Cancer
Authors: Nathan Paul , Zweifel Martin , Padhani Anwar R. , Koh Dow-Mu , Ng Matthew , Collins David J. , Harris Adrian , Carden Craig , Smythe Jon , Fisher Nita , Taylor N. Jane , Stirling J. James , Lu Shiao-Ping , Leach Martin O. , Rustin Gordon J.S. , Judson Ian
Published: May 2012

Purpose: The vascular disrupting agent (VDA) combretastatin A4 phosphate (CA4P) induces significant tumor necrosis as a single agent. Preclinical models have shown that the addition of an anti-VEGF antibody to a VDA attenuates the revascularization of the surviving tumor rim and thus significantly increases antitumor activity.

Experimental Design: Patients with advanced solid malignancies received CA4P at 45, 54, or 63 mg/m2 on day 1, day 8, and then every 14 days. Bevacizumab 10 mg/kg was given on day 8 and at subsequent cycles four hours after CA4P. Functional imaging with dynamic contrast enhanced-MRI (DCE-MRI) was conducted at baseline, after CA4P alone, and after cycle 1 CA4P + bevacizumab.

Results: A total of 63 mg/m2 CA4P + 10 mg/kg bevacizumab q14 is the recommended phase II dose. A total of 15 patients were enrolled. Dose-limiting toxicities were grade III asymptomatic atrial fibrillation and grade IV liver hemorrhage in a patient with a history of hemorrhage. Most common toxicities were hypertension, headache, lymphopenia, pruritus, and pyrexia. Asymptomatic electrocardiographic changes were seen in five patients. Nine of 14 patients experienced disease stabilization. A patient with ovarian cancer had a CA125 response lasting for more than a year. DCE-MRI showed statistically significant reductions in tumor perfusion/vascular permeability, which reversed after CA4P alone but which were sustained following bevacizumab. Circulating CD34+ and CD133+ bone marrow progenitors increased following CA4P as did VEGF and granulocyte colony-stimulating factor levels.

Conclusions: CA4P in combination with bevacizumab appears safe and well tolerated in this dosing schedule. CA4P induced profound vascular changes, which were maintained by the presence of bevacizumab. Clin Cancer Res; 18(12); 3428–39. ©2012 AACR.
Psychometric Properties of a Russian Version of the General Health Questionnaire-28
Authors: Ignatyev Yuriy , Assimov Marat , Aichberger Marion C. , Ivens Sebastian , Mir Jan , Dochshanov Dauren , Ströhle Andreas , Heinz Andreas , Mundt Adrian P.
Published: May 2012

Background: The 28-item General Health Questionnaire (GHQ-28) is a scaled version of the General Health Questionnaire that has been used internationally to screen for mental disorders in nonpsychiatric populations. There is great need to validate international screening instruments in the Russian language for their use in post-Soviet countries. Methods: 200 persons were surveyed in a deprived area of Almaty, Kazakhstan using the Russian version of the GHQ-28 and socioeconomic measures (income level, employment situation and education). We calculated the median and the mean GHQ-28 scores for different socioeconomic subgroups. The internal reliability was tested using Cronbach’s α coefficient and intersubscale correlations. We conducted an exploratory factor analysis using varimax rotation. Results: The median score of the GHQ-28 was 2 (mean = 3.56; SD = 5.09) for the total sample. Higher age, unemployment and female gender were significantly associated with high mean GHQ-28 scores. Cronbach’s α coefficient was 0.92 for the total scale. Exploratory factor analysis revealed four factors explaining 50.07% of the variance. The factor Anxiety/Insomnia accounted for 14.87%, Severe Depression for 13.74%, Social Dysfunction for 13.47% and Somatic Symptoms for 8.81% of the variance. Conclusions: The test showed good internal consistency. The median GHQ-28 score was relatively low compared to other countries. The subscale Severe Depression including items on suicidal ideation may have a lower acceptance than the other subscales Somatic Symptoms, Anxiety/Insomnia and Social Dysfunction.
Effect of Growth Differentiation Factor 5 on the Proliferation and Tenogenic Differentiation Potential of Human Mesenchymal Stem Cells in vitro
Authors: Tan Sik-Loo , Ahmad Raja Elina , Ahmad Tunku Sara , Merican Azhar M. , Abbas Azlina A. , Ng Wuey Min , Kamarul Tunku
Published: May 2012

The use of growth differentiation factor 5 (GDF-5) in damaged tendons has been shown to improve tendon repair. It has been hypothesized that further improvements may be achieved when GDF-5 is used to promote cell proliferation and induce tenogenic differentiation in human bone marrow-derived mesenchymal stem cells (hMSCs). However, the optimal conditions required to produce these effects on hMSCs have not been demonstrated in previous studies. A study to determine cell proliferation and tenogenic differentiation in hMSCs exposed to different concentrations of GDF-5 (0, 5, 25, 50, 100 and 500 ng/ml) was thus conducted. No significant changes were observed in the cell proliferation rate in hMSCs treated at different concentrations of GDF-5. GDF-5 appeared to induce tenogenic differentiation at 100 ng/ml, as reflected by (1) a significant increase in total collagen expression, similar to that of the primary native human tenocyte culture; (2) a significant upregulation in candidate tenogenic marker gene expression, i.e. scleraxis, tenascin-C and type-I collagen; (3) the ratio of type-I collagen to type-III collagen expression was elevated to levels similar to that of human tenocyte cultures, and (4) a significant downregulation of the non-tenogenic marker genes runt-related transcription factor 2 and sex determining region Y (SRY)-box 9 at day 7 of GDF-5 induction, further excluding hMSC differentiation into other lineages. In conclusion, GDF-5 does not alter the proliferation rates of hMSCs, but, instead, induces an optimal tenogenic differentiation response at 100 ng/ml.
Amelogenin Enhances the Osteogenic Differentiation of Mesenchymal Stem Cells Derived from Bone Marrow
Authors: Tanimoto K. , Huang Y.C. , Tanne Y. , Kunimatsu R. , Michida M. , Yoshioka M. , Ozaki N. , Sasamoto T. , Yoshimi Y. , Kato Y. , Tanne K.
Published: May 2012

Amelogenins are the major constituent of developing extracellular enamel matrix proteins and are understood to have an exclusively epithelial origin. Recent studies have demonstrated that amelogenins can be detected in other tissues, including bone marrow mesenchymal stem cells (MSCs), but the role of amelogenins in MSCs remains unclear. The purpose of this study was to examine the effect of recombinant human full-length amelogenin (rh174) on the osteogenic differentiation of cultured human MSCs. MSCs isolated from human bone marrow were cultured in osteoblastic differentiation medium with 0, 10 or 100 ng/ml rh174. The mRNA levels of bone markers were examined by real-time PCR analysis. Alkaline phosphatase (ALP) activity and calcium concentration were determined. Mineralization was evaluated by alizarin red staining. The mRNA levels of ALP, type I collagen, osteopontin and bone sialoprotein in the MSCs treated with rh174 became significantly higher than those in non-treated controls. Treatment of MSCs with rh174 also enhanced ALP activity and calcium concentration, resulting in enhanced mineralization, as denoted by high intensity of alizarin red staining. In conclusion, the present study showed that rh174 enhances the mineralization accompanied by the upregulation of bone markers in human bone marrow MSCs during osteogenic differentiation, suggesting a certain role of amelogenin in the modulation of osteogenic differentiation of MSCs.
Tako-Tsubo Cardiomyopathy Caused Immediately following Cesarean Section Delivery of Triplets: A Case Report
Authors: Shoji Tadahiro , Takatori Eriko , Oyama Rie , Kumagai Seisuke , Fukushima Akimune , Yoshizaki Akira , Sugiyama Toru
Published: May 2012

The name ‘tako-tsubo’ cardiomyopathy was initially used to describe a unique ‘short-neck round-flask’-shaped form of left ventricular apical ballooning, resembling a Japanese tako-tsubo, a jar (tsubo) used for capturing octopus (tako). Tako-tsubo cardiomyopathy exhibits acute onset, transient left ventricular apical wall motion abnormalities with chest symptoms and minimal myocardial enzymatic release, mimicking acute myocardial infarction in patients without angiographic stenosis on coronary angiography. There have been few case reports on tako-tsubo cardiomyopathy, and this disorder is especially rare in pregnant women. A 30-year-old woman who was pregnant with triplets, and had been treated with ritodrine hydrochloride for 12 weeks for threatened premature delivery, underwent cesarean section with spinal anesthesia at 30 weeks’ gestation. Three hours later, she complained of acute chest pain, dyspnea and episodes of unconsciousness. She was transferred to the intensive care unit and intubated for ventilatory support. We diagnosed heart failure due to tako-tsubo cardiomyopathy based on heart ultrasonography, blood tests, chest X-ray, electrocardiogram and myocardial scintigraphy. She was extubated from the ventilator after 3 days of catecholamine, furosemide and carperitide administration. She was discharged from the hospital on day 53 without symptoms.
Asymmetric Dimethylarginine Reduces Nitric Oxide Donor-Mediated Dilation of Arterioles by Activating the Vascular Renin-Angiotensin System and Reactive Oxygen Species
Authors: Veresh Zoltan , Debreczeni Bela , Hamar Janos , Kaminski Pawel M. , Wolin Michael S. , Koller Akos
Published: May 2012

Introduction: We tested the hypothesis that asymmetric dimethylarginine (ADMA) interferes with other mechanisms in addition to inhibition of nitric oxide synthase (NOS). Thus, in skeletal muscle arterioles, in the presence of ADMA, we investigated the dilator effect of an NO donor and increases in flow and aimed to elucidate the underlying mechanisms, including the role of oxidative stress, which is known to reduce the bioavailability of NO. Methods and Results: In isolated rat gracilis skeletal muscle arterioles (∼160 µm at 80 mm Hg), ADMA (similarly to pyrogallol) reduced dilations to sodium nitroprusside (SNP), which was significantly prevented by the presence of superoxide dismutase (SOD) and catalase (CAT): SNP 10–8M; control: 43.2 ± 3%, ADMA: 4.9 ± 1%, ADMA + SOD/CAT: 30.2 ± 9% (p < 0.05). Also, ADMA reduced basal diameter and flow-induced dilations, which were not restored by L-arginine, but prevented by SOD/CAT and by inhibition of NAD(P)H oxidase (but not xanthine oxidase) and by an angiotensin-converting enzyme inhibitor or an angiotensin type 1 receptor blocker (ARB). ADMA increased the production of reactive oxygen species detected by lucigenin-enhanced chemiluminescence, which was significantly inhibited by SNP or ARB. Conclusion: We suggest that by activating the vascular renin-angiotensin-NAD(P)H oxidase pathway, ADMA elicits oxidative stress, which interferes with the bioavailability of NO and consequently reduces NO-mediated dilations.
Differentiating between Confrontive and Coercive Kinds of Parental Power-Assertive Disciplinary Practices
Authors: Baumrind Diana
Published: May 2012

In this essay, I differentiate between coercive and confrontive kinds of power assertion to elucidate the significantly different effects on children’s well-being of authoritarian and authoritative styles of parental authority. Although both parenting styles (in contrast to the permissive style) are equally demanding, forceful, and power-assertive, they differ from each other in the characteristic kind of power they assert on their children to obtain compliance with parents’ demands. The kind of power that characterizes authoritarian parents is coercive (arbitrary, peremptory, domineering, and concerned with marking status distinctions), whereas the kind of power that characterizes authoritative parents is confrontive (reasoned, negotiable, outcome-oriented, and concerning with regulating behaviors). I argue that the effects of power assertion are detrimental only when coercive, so that the common presumption that power-assertive disciplinary practices per se are harmful is unjustified.
Could Chemical Enhancement of Gold Nanoparticle Penetration Be Extrapolated from Established Approaches for Drug Permeation?
Authors: Labouta H.I. , El-Khordagui L.K. , Schneider M.
Published: May 2012

Background and Aim: Investigations on chemical enhancement of skin penetration of gold nanoparticles are considered crucial to have a deeper insight into the main barrier of particle penetration. Methods: In this study, penetration of gold nanoparticles in the presence of several chemical enhancers – urea, sodium lauryl sulphate, polysorbate 80 and dimethyl sulfoxide (DMSO) – through human skin was studied. Results: Among the tested chemical enhancers, DMSO could induce the penetration of hydrophilic (citrate-stabilized) gold colloid of no intrinsic penetration ability in a concentration-dependent manner. Pretreatment of the skin with DMSO however reduced the penetration of hydrophobic (cetrimide-coated) gold nanoparticles as a result of aggregation in the top layers of the stratum corneum limiting penetration into the deeper skin layers. In addition, nanoparticles-vehicle interaction and the stability of the nanoparticles in the applied vehicle were found important determinants of skin penetration. Conclusion: Our results demonstrate that the already established approaches for chemical permeation enhancement of drug molecules and their postulated mechanisms could be used as preliminary guidelines for enhancing the penetration of nanoparticles. At this size range of 15 nm, intercellular lipids provide the main barrier to particle penetration through the stratum corneum.
Safety Assessment by Multiphoton Fluorescence/Second Harmonic Generation/Hyper-Rayleigh Scattering Tomography of ZnO Nanoparticles Used in Cosmetic Products
Authors: Darvin M.E. , König K. , Kellner-Hoefer M. , Breunig H.G. , Werncke W. , Meinke M.C. , Patzelt A. , Sterry W. , Lademann J.
Published: May 2012

Zinc oxide nanoparticles (ZnO NPs) are commonly used as UV filters in commercial sunscreen products. Their penetration into the skin is intensively discussed in the literature. In the present in vivo study, penetration of ZnO NPs (30 nm in size) into human skin was investigated by multiphoton tomography. Based on the non-linear effects of a second harmonic generation and hyper-Rayleigh scattering, the distribution of ZnO NPs in the horny layers of the epidermis, as well as the furrows, wrinkles and orifice of the hair follicles was analyzed. This method permitted distinguishing between the particulate and dissolved forms of Zn. A detection limit of 0.08 fg/µm3 was estimated. Taking advantage of this sensitivity, it was clearly shown that ZnO NPs penetrate only into the outermost layers of stratum corneum, furrows and into the orifices of the hair follicles and do not reach the viable epidermis.
Comparison of Invasive and Noninvasive Assessment of Aortic Stenosis Severity in the Elderly
Authors: Gertz Zachary M. , Raina Amresh , O'Donnell William , McCauley Brian D. , Shellenberger Charlene , Kolansky Daniel M. , Wilensky Robert L. , Forfia Paul R. , Herrmann Howard C.
Published: May 2012

Background—

Aortic valve area (AVA) in aortic stenosis (AS) can be assessed noninvasively or invasively, typically with similar results. These techniques have not been validated in elderly patients, where common assumptions make them most prone to error. Accurate assessment of AVA is crucial to determine which patients are appropriate candidates for aortic valve replacement.

Methods and Results—

Fifty elderly patients (mean 86 years, 46% female) referred for cardiac catheterization to evaluate AS also underwent transthoracic echocardiography within 24 hours. To minimize assumptions all patients had 3-dimensional echocardiography (Echo-3D), and at catheterization using directly measured oxygen consumption (Cath-mVo
2
) and thermodilution cardiac output (Cath-TD). Correlation between Cath-mVo
2
and Echo-3D AVA was poor (
r
=0.41). Cath-TD AVA had a moderate correlation with Echo-3D AVA (
r
=0.59). Cath-mVo
2
(AVA=0.69 cm
2
) and Cath-TD (AVA=0.66 cm
2
) underestimated AVA compared with Echo-3D (AVA=0.76 cm
2;
P
=0.08 for comparison with Cath-mVo
2
;
P
=0.001 for Cath-TD). Compared with Echo-3D, the sensitivity and specificity for determining critical disease (AVA <0.8 cm
2
) were 81% and 42% for Cath-mVo
2
, and 97% and 53% for Cath-TD. The only independent predictor of the difference between noninvasive and invasive AVA was stroke volume index (
P
<0.01). Resistance, a less flow-dependent measure, showed a stronger correlation between Echo-3D and Cath-mVo
2
(
r
=0.69), and Echo-3D and Cath-TD (
r
=0.77).

Conclusions—

Standard techniques of AVA assessment for AS show poor correlation in elderly patients, with frequent misclassification of critical AS. Less flow-dependent measures, such as resistance, should be considered to ensure that only appropriate patients are treated with aortic valve replacement.
Rapid Onset of Renal Sympathetic Nerve Activation in Rabbits Fed a High-Fat Diet
Authors: Armitage James A. , Burke Sandra L. , Prior Larissa J. , Barzel Benjamin , Eikelis Nina , Lim Kyungjoon , Head Geoffrey A.
Published: May 2012

Hypertension and elevated sympathetic drive result from consumption of a high-calorie diet and deposition of abdominal fat, but the etiology and temporal characteristics are unknown. Rabbits instrumented for telemetric recording of arterial pressure and renal sympathetic nerve activity (RSNA) were fed a high-fat diet for 3 weeks then control diet for 1 week or control diet for 4 weeks. Baroreflexes and responses to air-jet stress and hypoxia were determined weekly. After 1 week of high-fat diet, caloric intake increased by 62%, accompanied by elevated body weight, blood glucose, plasma insulin, and leptin (8%, 14%, 134%, and 252%, respectively). Mean arterial pressure, heart rate, and RSNA also increased after 1 week (6%, 11%, and 57%, respectively). Whereas mean arterial pressure and body weight continued to rise over 3 weeks of high-fat diet, heart rate and RSNA did not change further. The RSNA baroreflex was attenuated from the first week of the diet. Excitatory responses to air-jet stress diminished over 3 weeks of high-fat diet, but responses to hypoxia were invariant. Resumption of a normal diet returned glucose, insulin, leptin, and heart rate to control levels, but body weight, mean arterial pressure, and RSNA remained elevated. In conclusion, elevated sympathetic drive and impaired baroreflex function, which occur within 1 week of consumption of a high-fat, high-calorie diet, appear integral to the rapid development of obesity-related hypertension. Increased plasma leptin and insulin may contribute to the initiation of hypertension but are not required for maintenance of mean arterial pressure, which likely lies in alterations in the response of neurons in the hypothalamus.
Low Placental Growth Factor Across Pregnancy Identifies a Subset of Women With Preterm Preeclampsia
Authors: Powers Robert W. , Roberts James M. , Plymire Daniel A. , Pucci Dominick , Datwyler Saul A. , Laird Don M. , Sogin David C. , Jeyabalan Arun , Hubel Carl A. , Gandley Robin E.
Published: May 2012

Preeclampsia is a heterogeneous syndrome affecting 3% to 5% of all pregnancies. An imbalance of the antiangiogenic and proangiogenic factors, soluble receptor fms-like tyrosine kinase 1 and placental growth factor (PGF), is thought to contribute to the pathophysiology of preeclampsia. Maternal plasma PGF and soluble receptor fms-like tyrosine kinase 1 were quantified by specific immunoassays in cross-sectional samples from 130 preeclamptic subjects and 342 normotensive controls at delivery and longitudinally in samples from 50 women who developed preeclampsia and 250 normotensive controls. Among women who developed preeclampsia, 46% (n=23) evidenced a pattern of consistently low maternal PGF across pregnancy below the lower 95% CI of controls from 15 weeks' gestation to term. In contrast, the remaining 54% (n=27) of women who developed preeclampsia had maternal PGF concentrations similar to or above (n=7) those of normotensive controls. Subjects with low PGF across pregnancy who developed preeclampsia evidenced significantly higher blood pressure in early pregnancy (
P
<0.05) and, after diagnosis, earlier gestational age at delivery (
P
<0.05) and more preterm birth (
P
<0.05) compared with preeclamptic patients with high PGF. A significant subset of women who develop preeclampsia show evidence of consistently low PGF across pregnancy. Low PGF with preeclampsia was associated with preterm delivery compared with preeclamptic patients with high PGF. Identifying women with consistently low plasma PGF during pregnancy may provide a greater understanding of preeclampsia pathophysiology and may provide more focused research and clinical activities.
Hypertension in Aortic Stenosis
Authors: Rieck Åshild E. , Cramariuc Dana , Boman Kurt , Gohlke-Bärwolf Christa , Staal Eva M. , Lønnebakken Mai Tone , Rossebø Anne B. , Gerdts Eva
Published: May 2012

The impact of hypertension on left ventricular structure and outcome during progression of aortic valve stenosis has not been reported from a large prospective study. Data from 1616 patients with asymptomatic aortic stenosis randomized to placebo-controlled treatment with combined simvastatin and ezetimibe in the Simvastatin Ezetimibe in Aortic Stenosis Study were used. The primary study end point included combined cardiovascular death, aortic valve events, and ischemic cardiovascular events. Hypertension was defined as history of hypertension or elevated baseline blood pressure. Left ventricular hypertrophy was defined as left ventricular mass/height
2.7
≥46.7 g/m
2.7
in women and ≥49.2 g/m
2.7
in men and concentric geometry as relative wall thickness ≥0.43. Baseline peak aortic jet velocity and aortic stenosis progression rate did not differ between hypertensive (n=1340) and normotensive (n=276) patients. During 4.3 years of follow-up, the prevalence of concentric left ventricular hypertrophy increased 3 times in both groups. Hypertension predicted 51% higher incidence of abnormal LV geometry at final study visit independent of other confounders (
P
<0.01). In time-varying Cox regression, hypertension did not predict increased rate of the primary study end point. However, hypertension was associated with a 56% higher rate of ischemic cardiovascular events and a 2-fold increased mortality (both
P
<0.01), independent of aortic stenosis severity, abnormal left ventricular geometry, in-treatment systolic blood pressure, and randomized study treatment. No impact on aortic valve replacement was found. In conclusion, among patients with initial asymptomatic mild-to-moderate aortic stenosis, hypertension was associated with more abnormal left ventricular structure and increased cardiovascular morbidity and mortality.
Numerical Tests of the Weak Pressure Gradient Approximation
Authors: Romps David M.
Published: May 2012

Cloud-resolving simulations of convection over a surface temperature hot spot are used to evaluate the weak pressure gradient (WPG) and weak temperature gradient (WTG) approximations. The premise of the relaxed form of WTG—that vertical velocity is equal to buoyancy times a positive time scale—is found to be violated by thick layers of negative buoyancy in steady-state ascent. The premise of WPG—that horizontal divergence and pressure anomalies are collocated—is validated by these simulations. When implemented in a cloud-resolving model, WPG replicates buoyancy transients exceptionally well, including the adiabatic lifting of air below buoyancy anomalies. WTG captures neither this effect nor the associated triggering of moist convection. For steady states, WTG produces vertical velocity profiles that are too top heavy. On the other hand, WPG generates velocity profiles that closely match fully resolved hot-spot simulations. Taken together, the evidence suggests that WPG is a relatively accurate method for parameterizing supradomain-scale (SDS) dynamics.
Reconstructing the South Pacific Convergence Zone Position during the Presatellite Era: A La Niña Case Study
Authors: Lorrey Andrew , Dalu Giovanni , Renwick James , Diamond Howard , Gaetani Marco
Published: May 2012

Sixty-four southwest Pacific island meteorological stations were used to develop ENSO-related austral warm season (November–April) rainfall climatologies for 1961–90. Historical data for the same station set were then examined for 1955/56, one of the strongest La Niñas of the twentieth century. The pattern for that event was typical of a well-coupled protracted La Niña, with above-normal rainfall (>150%) observed for 17 stations in the case study.

Tropical cyclone tracks were also used to illustrate the proximal effects of historical storms on station rainfall. Several stations that were located along the northern edge of the tropical cyclone swarm, but south of a region of anomalously low rainfall, were selected as possible candidates having been close to the mean South Pacific convergence zone (SPCZ) location. Linear interpolations between those stations highlighted a likely SPCZ position for the 1955/56 event.

The reconstructed SPCZ location indicated a position southwest of normal, consistent with many La Niñas observed during the satellite era. The 1955/56 SPCZ reconstruction compared favorably with NOAA Cooperative Institute for Research in Environmental Sciences (CIRES) twentieth-century reanalysis (20CR) positions of maximum atmospheric water content and omega (time derivative of pressure that illustrates vertical velocity, and a proxy for convection and SPCZ location) at 500 hPa. Comparisons between Global Precipitation Climatology Project (GPCP) warm season rainfall composite plots for several satellite era La Niñas and one well-coupled La Niña event that occurred during 2010/11 to omega at 500 hPa and maximum rainfall amounts suggest that the 1955/56 reconstruction from in situ rainfall measurements captured the SPCZ location. These findings suggest that use of the 20CR could help to identify hemispheric-scale atmospheric circulation features like the SPCZ and improve understanding of ENSO dynamics prior to the satellite era.
Impact of Stochastic Physics in a Convection-Permitting Ensemble
Authors: Bouttier François , Vié Benoît , Nuissier Olivier , Raynaud Laure
Published: May 2012

A stochastic physics scheme is tested in the Application of Research to Operations at Mesoscale (AROME) short-range convection-permitting ensemble prediction system. It is an adaptation of ECMWF’s stochastic perturbation of physics tendencies (SPPT) scheme. The probabilistic performance of the AROME model ensemble is found to be significantly improved, when verified against observations over two 2-week periods. The main improvement lies in the ensemble reliability and the spread–skill consistency. Probabilistic scores for several weather parameters are improved. The tendency perturbations have zero mean, but the stochastic perturbations have systematic effects on the model output, which explains much of the score improvement. Ensemble spread is an increasing function of the SPPT space and time correlations. A case study reveals that stochastic physics do not simply increase ensemble spread, they also tend to smooth out high-spread areas over wider geographical areas. Although the ensemble design lacks surface perturbations, there is a significant end impact of SPPT on low-level fields through physical interactions in the atmospheric model.
‘Even if we Meet in Heaven We Will Fight’: British Colonial Policies and Aguleri/Umuleri Conflicts in Southeastern Nigeria
Authors: Onwuzuruigbo Ifeanyi
Published: May 2012

Accepting that the Land Question was only limited to former settler colonies in Africa such as Kenya and Zimbabwe, dominant opinion in the literature has tended to trivialize the bitter struggles for land, many of which began during the colonial dispensation in many African nations. With globalization, democratization, structural adjustment and intensification of identity politics, many of these land conflicts have lingered. Yet studies of the conflicts, as in the case of Aguleri/Umuleri, have been scanty and almost ignore their historical and colonial roots. This paper explores colonial foundations of Aguleri/Umuleri conflicts, colonial policies designed to manage them and why they failed.
Mechanical properties and corrosion behaviour of fly ash particles reinforced AA 2024 composites
Authors: Rao J Babu , Rao D Venkata , Murthy I Narasimha , Bhargava NRMR
Published: May 2012

Composites are most promising materials of recent interest. Metal matrix composites (MMCs) possess significantly improved properties compared to unreinforced alloys. There has been an increasing interest in composites containing low density and low cost reinforcements. Hence, composites with fly ash as reinforcement are likely to over come thecost barrier for wide spread applications in automotive and small engine applications. In the present investigation, AA 2024 alloy – 2 to 10 wt% fly ash composites were made by stir casting route. Phase identification and structural characterization was carried out on fly ash by X-ray diffraction studies. Scanning electron microscopy and optical microscopy was used for microstructure analysis. The hardness, compression and pitting corrosion tests were carried out on all these alloy and composites. The SEM studies reveal that there was a uniform distribution of fly ash particles in the matrix phase and also very good bonding is exist between the matrix and reinforcement. With increasing the amount of fly ash the density of the composites was decreased and the hardness was increased. The increase in compression strength was observed with increase in amount of fly ash. Fly ash particles lead to an enhanced pitting corrosion of the aluminium–fly ash (ALFA) composites in comparison with unreinforced matrix (AA 2024 alloy). The enhanced pitting corrosion of ALFA composites is associated with the introduction of nobler second phase of fly ash particles.
Zapatista and counter-Zapatista protests
Authors: Inclán María
Published: May 2012

This study represents the first systematic analysis of the interactions between pro-Zapatista and counter-Zapatista protestors in Chiapas, Mexico, and the first empirical test of movement–countermovement theories in a transitional democracy. Three claims are tested: (1) movement protests trigger countermovement protest activity; (2) different political parties at different levels of government trigger movement–countermovement protest activity; and (3) victories won by one side of a conflict, viewed as procedural concessions, trigger further pro- and countermovement protest activity. These hypotheses are tested using negative binomial models and data on Zapatista-related protest activity between 1994 and 2003. The results show that: (1) movement and countermovement protests have a positive, reciprocal effect on both groups' future protest activity; (2) movement and countermovement protesting groups use the dominant political party as a target of protest. The characteristics of the electoral cycle and rise of multi-party competition at all levels of government do not have a consistent effect on protest activity; (3) granting procedural concessions to pro-movement actors generates more protest activity among both groups. However, granting procedural concessions via social programs and public works to the population irrespective of its sympathy to either side of the movement–countermovement conflict decreases movement protests and increases countermovement protests.
Dueling incentives
Authors: Cohen Dara Kay , Green Amelia Hoover
Published: May 2012

Transnational advocacy organizations are influential actors in the international politics of human rights. While political scientists have described several methods these groups use – particularly a set of strategies termed ‘information politics’ – scholars have yet to consider the effects of these tactics beyond their immediate impact on public awareness, policy agendas or the behavior of state actors. This article investigates the information politics surrounding sexual violence during Liberia’s civil war. We show that two frequently-cited ‘facts’ about rape in Liberia are inaccurate, and consider how this conventional wisdom gained acceptance. Drawing on the Liberian case and findings from sociology and economics, we develop a theoretical framework that treats inaccurate claims as an effect of ‘dueling incentives’ – the conflict between advocacy organizations’ needs for short-term drama and long-term credibility. From this theoretical framework, we generate hypotheses regarding the effects of information politics on (1) short-term changes in funding for human rights advocacy organizations, (2) short-term changes in human rights outcomes, (3) the institutional health of humanitarian and human rights organizations, and (4) long-run outcomes for the ostensible beneficiaries of such organizations. We conclude by outlining a research agenda in this area, emphasizing the importance of empirical research on information politics in the human rights realm, and particularly its effects on the lives of aid recipients.
Social Identity Complexity and Immigrants’ Attitude Toward the Host Nation
Authors: Verkuyten Maykel , Martinovic Borja
Published: May 2012

Social identity complexity refers to individual differences in the interrelationships among multiple ingroup identities. The present research conducted in the Netherlands examines social identity complexity in relation to Muslim immigrants’ national identification and the attitude toward the host majority. Three studies are reported that focused on the interrelationship between ethnicity and religion and examined social identity complexity in different ways. Study 1 showed that lower social identity complexity is associated with lower national identification. Studies 2 and 3 examined the interaction between ethnic and religious group identification. For Muslim identifiers, higher ethnic identification was related to lower national identification and higher ingroup bias (Studies 2) and lower endorsement of national liberal practices (Study 3). In contrast, for those who did not strongly identify with Muslims, higher ethnic identification was associated with higher national identification, stronger endorsement of Dutch liberal practices, and more positive stereotypes about the Dutch outgroup (Study 3).
Jonathan E. Rhoads Lecture 2012
Authors: Dickerson Roland N.
Published: May 2012

Practice‐based research plays a pivotal role for improving patient care as its primary intent is to solve a clinical dilemma or problem encountered in clinical practice. Its results are immediately applicable to day‐to‐day clinical practice and essential to the growth of an evidence‐based clinical practice. This review emphasizes the importance of this type of research. In addition, it serves to identify common sources for project conception and gives examples based on personal experiences of the author as a clinical practitioner, educator, and researcher. Common barriers to practice‐based research are discussed as well as potential solutions offered for consideration.
Resource-Based and Institutional Perspectives on Export Channel Selection and Export Performance
Authors: He Xinming , Brouthers Keith D. , Filatotchev Igor
Published: May 2012

Exporting is a critically important strategy for firms to grow, yet research in this area has tended to ignore how firms can leverage resource-based capabilities to improve export performance. Building on the resource-based view and institutional theory, the authors develop a novel perspective to explain how a firm can improve export performance by aligning its export channel with its level of market orientation capabilities, contingent on the institutional distance between home and export markets. Using a unique database of Chinese exporters, the authors find that exporters with strong market orientation capabilities prefer hierarchical export channels, while those with weak market orientation capabilities prefer hybrid channels. The analysis also indicates that the institutional distance between China and the export market moderates this relation. Moreover, the authors find that aligning export channel choice with firm-level market orientation capabilities and institutional distance yields better export performance.
Expression Pattern of Apurinic/Apyrimidinic Endonuclease in Sinonasal Squamous Cell Carcinoma
Authors: Lee Jin Woo , Jin Jun , Rha Ki‐Sang , Kim Yong Min
Published: May 2012

Objective

To evaluate the apurinic/apyrimidinic endonuclease 1 (APE1) expression in sinonasal squamous cell carcinomas (SCC) and to examine the correlation between APE1 expression patterns and various clinicopathological factors associated with sinonasal SCC that include SCC with inverted papilloma (SCCwIP) and SCC alone.

Study Design

Case‐control study.

Setting

Chungnam National University Hospital.

Subjects and Methods

The expressions of APE1 were analyzed by means of immunohistochemistry in 30 sinonasal SCC, including 14 SCC patients associated with IP and 16 patients with SCC alone. A total of 19 patients who had been diagnosed with chronic rhinosinusitis with nasal polyposis and who required endoscopic sinus surgery were used as the control group. The degrees of APE1 expression were analyzed with respect to the following clinicopathologic variables: age, sex, T stage, histologic differentiation, distant metastasis, and recurrence.

Results

Cytoplasmic staining of APE1 was significantly higher in SCC compared with SCCwIP (68.75% vs 14.29%). Cytoplasmic staining of APE1 was significantly associated with T stage (P =. 044) in SCC and histologic grade (P =. 0025) in sinonasal SCC. Nuclear staining of APE1 was significantly associated with distant metastasis (P =. 022) in SCC.

Conclusion

These results suggest that the nuclear and cytoplasmic expression of APE1 may be related to tumor invasiveness and prognosis in sinonasal SCC. The suppression of APE1 expression can potentially be a new target for future sinonasal SCC therapies.
Mitomycin C–Enhanced Revision Endoscopic Dacryocystorhinostomy
Authors: Ragab Sameh M. , Elsherif Hossam S. , Shehata Emad M. , Younes Ahmed , Gamea Ahmed M.
Published: May 2012

Objectives

(1) To conduct an adequately powered randomized controlled trial investigating the safety and efficacy of mitomycin C–enhanced revision endoscopic dacryocystorhinostomy (DCR) and (2) to analyze causes of failure after primary endoscopic DCR.

Study Design

A randomized controlled study.

Setting

General hospital.

Subjects and Methods

Seventy‐six revision endoscopic DCRs were randomized into 2 groups: endoscopic DCR with mitomycin (group I), where 0.5 mg/mL mitomycin C was applied for 10 minutes, and endoscopic DCR without mitomycin (group II). Follow‐up settings were done to document the patient’s subjective improvement, to judge ostium patency on irrigation, and to record any complications.

Results

Causes of failure in the original 92 patients included canalicular obstruction (14%), small misplaced bony window (43%), very small nasolacrimal stoma due to development of synechia (23%), and complete closure of nasolacrimal stoma with tough fibrous tissue (63%). There was no significant difference between the 2 groups in subjective and objective success rates and adverse events. Group I demonstrated a significantly longer operative time and a significantly lower number of debridement sessions (mean of 1.2 vs 1.9).

Conclusions

Recurrent nasolacrimal duct obstruction after primary endoscopic DCR is mainly due to reclosure of the nasolacrimal stoma with synechia and fashioning of the small misplaced bony window. Mitomycin C does not increase the success rate of revision endoscopic DCR. It is a safe procedure and may be of value only in patients inaccessible to strict follow‐up because it induces a better healing profile in terms of mucosal recovery, wound healing, and less need for debridement sessions.