bluuebunny/crossref_metadata_2025 huggingface dataset:
NUMERICAL ANALYSIS ON PROGRESSIVE FRACTURE BEHAVIOR BY USING ELEMENT-FREE METHOD BASED ON FINITE COVERS
Authors: LUAN MAOTIAN , YANG XINHUI , TIAN RONG , YANG QING
Published: March 2006

The finite-cover element-free method FCEFM is applied to simulate the fracture and damage evolution process of geo-materials. This method is mathematically based on the finite-cover technique of manifold method and the multiple weighted moving least-square method to solve the continuous and discontinuous problems without meshing or re-meshing. The damage heterogeneity and evolutionary processes of rock mass with initial cracks are analyzed and numerically simulated by FCEFM. Using the method of probability to generate the parameters of materials randomly, the physical and mechanical properties of materials are randomly distributed in nodes or Gaussian points. And an alternating damage model together with numerical implementation which is adapted to microscopic elasto-brittle fracture analysis is proposed. Through analysis of several numerical examples, the validity and efficiency of progressive fracture analysis with use of the proposed FCEFM is demonstrated.
THE STUDY OF KERNEL FUNCTIONS IN IMPACT PROBLEM SIMULATION BY USING SPH METHOD
Authors: XU FEI , KIKUCHI MASANORI
Published: March 2006

In this paper, the numerical convergence, accuracy, stability, efficiency, and reality of the SPH simulation of the impact problem are analyzed by using several different kernel functions. Three are traditional kernel functions of the quadratic function, the cubic bell function, and the quintic function. Others are their corresponding corrected zero-order consistency kernel functions with different denominators. Several unnoticed features in the formulations and the simulation results of the corrected kernel are pointed out. The availability of these kernel functions on the impact problem is discussed. To achieve reality, an unphysical adhesive phenomenon is avoided by introducing three separation conditions.
VARIATIONAL MULTISCALE ANALYSIS OF SOLIDS WITH STRAIN GRADIENT PLASTIC EFFECTS USING MESHFREE APPROXIMATION
Authors: YEON JEOUNG-HEUM , YOUN SUNG-KIE
Published: March 2006

A meshfree multiscale method is presented for efficient analysis of solids with strain gradient plastic effects. In the analysis of strain gradient plastic solids, localization due to increased hardening of strain gradient effect appears. Chen-Wang theory is adopted, as a strain gradient plasticity theory. It represents strain gradient effects as an internal variable and retains the essential structure of classical plasticity theory. In this work, the scale decomposition is carried out based on variational form of the problem. Coarse scale is designed to represent global behavior and fine scale to represent local behavior and gradient effect by using the intrinsic length scale. From the detection of high strain gradient region, fine scale region is adopted. Each scale variable is approximated using meshfree method. Meshfree approximation is well suited for adaptivity. As a method of increasing resolution, partition of unity based extrinsic enrichment is used. Each scale problem is solved iteratively. The proposed method is applied to bending of a thin beam and bimaterial shear layer and micro-indentation problems. Size effects can be effectively captured in the results of the analysis.
SOME EXAMPLES OF THE METHOD OF FINITE SPHERES WITH ENRICHMENT
Authors: MACRI MICHAEL , TICHY JOHN , DE SUVRANU
Published: March 2006

In this paper we provide some examples where the method of finite spheres, a truly meshfree numerical technique, is enriched by functions derived from asymptotic solutions of the governing differential equations in the vicinity of singularities. Specifically, we demonstrate the effectiveness of this technique for the analysis of an elastic double edge notched tension specimen and an elastic domain indented with a right-sided rigid punch under slip and no slip conditions. The solutions are compared with those obtained using the method of finite spheres without enrichment and the traditional finite element method.
A LINEARLY CONFORMING POINT INTERPOLATION METHOD (LC-PIM) FOR 2D SOLID MECHANICS PROBLEMS
Authors: LIU G. R. , ZHANG G. Y. , DAI K. Y. , WANG Y. Y. , ZHONG Z. H. , LI G. Y. , HAN X.
Published: March 2006

A linearly conforming point interpolation method (LC-PIM) is developed for 2D solid problems. In this method, shape functions are generated using the polynomial basis functions and a scheme for the selection of local supporting nodes based on background cells is suggested, which can always ensure the moment matrix is invertible as long as there are no coincide nodes. Galerkin weak form is adopted for creating discretized system equations, and a nodal integration scheme with strain smoothing operation is used to perform the numerical integration. The present LC-PIM can guarantee linear exactness and monotonic convergence for the numerical results. Numerical examples are used to examine the present method in terms of accuracy, convergence, and efficiency. Compared with the finite element method (FEM) using linear triangle elements and the radial point interpolation method (RPIM) using Gauss integration, the LC-PIM can achieve higher convergence rate and better efficiency.
MESHFREE METHODS AND THEIR COMPARISONS
Authors: GU Y. T.
Published: March 2006

In recent years, one of the hottest topics in computational mechanics is the meshfree or meshless method. Increasing number of researchers are devoting themselves to the research of the meshfree methods, and a group of meshfree methods have been proposed and used to solve the ordinary differential equations (ODEs) or the partial differential equations (PDE). In the meantime, meshfree methods are being applied to a growing number of practical engineering problems. In this paper, a detailed discussion will be provided on the development of meshfree methods. First, categories of meshfree methods are introduced. Second, the methods for constructing meshfree shape functions are discussed, and the interpolation qualities of them are also studied using the surface fitting. Third, several typical meshfree methods are introduced and compared with each others in terms of their accuracy, convergence and effectivity. Finally, the major technical issues in meshfree methods are discussed, and the future development of meshfree methods is addressed.
Cladosporium herbarum and Pityrosporum ovale Allergen Extracts Share Cross-Reacting Glycoproteins
Authors: Leino Marina , Reijula Kari , Mäkinen-Kiljunen Soili , Haahtela Tari , Mäkelä Mika J. , Alenius Harri
Published: March 2006

Background: Patients sensitized to airborne fungi such as Alternaria alternata and Cladosporium herbarum often also show positive skin prick test results and specific serum IgE antibodies to a yeast, Pityrosporum ovale. We examined whether part of the IgE binding to these fungi is explained by cross-reacting mould and yeast allergens. Methods: Serum samples from 36 patients with positive skin prick test to A. alternata or C. herbarum were analyzed for IgE antibodies to fungal extracts by ELISA and immunoblot analysis. Cross-reactivity between mould and yeast extracts was studied by ELISA and immunoblot inhibition assays. In further analysis, the mannan-containing glycoproteins were removed from the yeast extract by concanavalin A-Sepharose chromatography, and the IgE binding properties of the extracts were compared. Results: SerumIgE reactivity to P. ovale was found in 40% of the mould-sensitized patients. The IgE antibody binding to A. alternata and C. herbarum moulds was partially inhibited by the yeast P. ovale in ELISA and immunoblot inhibition assays. When the glycoproteins were removed from the extract, cross-reactivity was markedly reduced. Conclusion: Part of the IgE binding to mould and yeast allergen extracts is due to cross-reacting glycoproteins. False-positive IgE and skin prick test results should be taken into account in the diagnosis of mould allergy.
Effect of Membrane Sweeping at Term Pregnancy on Duration of Pregnancy and Labor Induction: A Randomized Trial
Authors: Kashanian Maryam , Akbarian Abdolrasool , Baradaran Hamid , Samiee Mitra Meshki
Published: March 2006

Aim: To evaluate the efficacy of sweeping of fetal membranes for induction of labor in uncomplicated term pregnancies. Methods: A randomized controlled trial was performed in 122 pregnant women beyond 39 weeks of gestation with no complications. The women were assigned to have their membranes swept or not (controls) for labor induction. The main outcome measures included duration of pregnancy and possible complications of sweeping of membranes, including rupture of membranes, postpartum infections, and vaginal bleeding. Results: Twenty-one patients did not give birth in our hospital and were, therefore, excluded from the study; 101 women completed the study (51 patients in the control group and 50 women in the study group). There were no statistically significant differences in maternal age, parity, birth weight, and Bishop score in the two groups. The mean interval between sweeping (stripping) and vaginal examination until delivery was 7.7 ± (SD) 6.9 and 7.1 ± 5.6 days in the sweeping and in the control group, respectively (p = 0.61). Of the 101 pregnant women, only 6 patients had premature rupture of membranes (2 in the sweeping group and 4 in the control group). There were no statistically significant differences between these individuals (p = 0.68). Significant vaginal bleeding was not observed in the two groups. Meconium-stained amniotic fluid was seen in 13 women: 8 in the sweeping group and 5 in the control group. There were no statistically significant differences among the women who had meconium-stained fluid in case and control groups (p = 0.39).There were no differences between women who had puerperal fever (3 in the sweeping group and 2 in the control group; p = 0.68).12 of the 101 women (6 in each group) had cesarean section performed, but there was no difference betweeen the two groups. Conclusion: Sweeping of membranes at 39 weeks of gestation has no significant clinical effect on the duration of pregnancy.
Orbitofrontal Dysfunction Related to Both Apathy and Disinhibition in Frontotemporal Dementia
Authors: Peters Frédéric , Perani Daniela , Herholz Karl , Holthoff Vjera , Beuthien-Baumann Bettina , Sorbi Sandro , Pupi Alberto , Degueldre Christian , Lemaire Christian , Collette Fabienne , Salmon Eric
Published: March 2006

Orbitofrontal metabolic impairment is characteristic of the frontal variant of frontotemporal dementia (fv-FTD), as are early changes in emotional and social conduct. Two main types of behavioral disturbances have been distinguished in fv-FTD patients: apathetic and disinhibited manifestations. In this study, we searched for relationships between brain metabolism and presence of apathetic or disinhibited behavior. Metabolic activity and behavioral data were collected in 41 fv-FTD patients from European PET centers. A conjunction analysis of the PET data showed an expected impairment of metabolic activity in the anterior cingulate, ventromedial and orbital prefrontal cortex, the dorsolateral prefrontal cortex and the left anterior insula in fv-FTD subjects compared to matched controls. A correlation was observed between disinhibition scores on the Neuropsychiatric Inventory scale and a cluster of voxels located in the posterior orbitofrontal cortex (6, 28, –24). Comparison of brain activity between apathetic and nonapathetic fv-FTD patients from two centers also revealed a specific involvement of the posterior orbitofrontal cortex in apathetic subjects (4, 22, –22). The results confirm that the main cerebral metabolic impairment in fv-FTD patients affects areas specializing in emotional evaluation and demonstrate that decreased orbitofrontal activity is related to both disinhibited and apathetic syndromes in fv-FTD.
Long-Term Intake of North American Ginseng Has No Effect on 24-Hour Blood Pressure and Renal Function
Authors: Stavro P. Mark , Woo Minna , Leiter Lawrence A. , Heim Tibor F. , Sievenpiper John L. , Vuksan Vladimir
Published: March 2006

Ginseng is consumed by 10% to 20% of adults in Asia and by up to 5% in Western countries. Despite observational evidence suggesting a link between its intake and the development of hypertension, there remains no long-term scrutiny for its effect on blood pressure (BP). We therefore undertook a randomized, placebo-controlled, double-blinded, crossover trial in 52 hypertensive individuals to determine the effect of 12-week North American ginseng intake on 24-hour BP; we also measured serum cystatin C as a marker of renal function. After a 4-week placebo run-in, we randomly assigned 52 participants to 3 g/day of ginseng or placebo for 12 weeks. This was followed by an 8-week washout and a subsequent 12-week period in which the opposite treatment was administered. At run-in and at weeks 0 and 12 of each treatment period, participants were fitted with an ambulatory BP monitor to assess 24-hour BP. The primary outcome was the treatment difference at week 12 in mean 24-hour systolic BP. Secondary outcomes were treatment differences at week 12 in other ambulatory BP parameters and serum cystatin C. Forty participants (77%) completed the trial, with 3 removed from main analysis (n=2, antihypertensive drug changes; n=1, incomplete ambulatory monitoring). In the remaining 37, 12-week ginseng treatment was associated with a neutral effect on all ambulatory BP parameters compared with placebo; an intention-to-treat analysis supported this. Ginseng did not affect serum cystatin C level. Overall, long-term ginseng use had no effect on 24-hour BP and renal function in hypertensive individuals.
Rapid Nongenomic Effects of Aldosterone on the Renal Vasculature in Humans
Authors: Schmidt Bernhard M.W. , Sammer Ulla , Fleischmann Ingrid , Schlaich Markus , Delles Christian , Schmieder Roland E.
Published: March 2006

There is increasing evidence for the importance of rapid nongenomic effects of aldosterone on the human vasculature. In vitro animal experiments in renal arterioles also suggest the presence of such effects on the renal vasculature. We conducted a clinical study to explore these effects in vivo in humans. Thirteen healthy male volunteers were examined. Aldosterone (500 μg) or placebo was injected intravenously with or without coinfusion of N(G) monomethyl-l-arginine (l-NMMA) in a randomized, double-blinded 4-fold crossover design. Renal plasma flow and glomerular filtration rate were measured by constant infusion clearance technique using inulin andpara-aminohippuric acid. Injection of aldosterone without concomitant infusion ofl-NMMA changed the renal plasma flow and glomerular filtration rate not statistically significant compared with placebo. Coinfusion ofl-NMMA unmasked the effect of aldosterone: aldosterone withl-NMMA decreased the glomerular filtration rate slightly (−1.4±6.2 mL/min), whereas infusion ofl-NMMA alone increased the glomerular filtration rate (8.3±9.8 mL/min;P=0.004).l-NMMA alone decreased renal plasma flow by 58.2±97.5 mL/min, and aldosterone withl-NMMA decreased renal plasma flow by 190.0±213.7 mL/min (P=0.074). Accordingly, Aldosterone withl-NMMA increased renal vascular resistance much more thanl-NMMA alone (1588±237 versus 614±240 dyn×s×cm−5;P=0.014). These data indicate that aldosterone acts via rapid nongenomic effects in vivo in humans at the renal vasculature. Antagonizing the endothelial NO synthase unmasks these effects. Therefore, rapid nongenomic aldosterone effects increase renal vascular resistance and thereby mediate arterial hypertension if endothelial dysfunction is present.
Value of Noninvasive Hemodynamics to Achieve Blood Pressure Control in Hypertensive Subjects
Authors: Smith Ronald D. , Levy Pavel , Ferrario Carlos M.
Published: March 2006

Abnormal hemodynamics play a central role in the development and perpetuation of high blood pressure. We hypothesized that hypertension therapy guided by noninvasive hemodynamics with impedance cardiography could aid primary care physicians in reducing blood pressure more effectively. Uncontrolled hypertensive patients on 1 to 3 medications were randomized by 3:2 ratio to either a standard arm or hemodynamic arm that used impedance cardiography (BioZ, CardioDynamics). Each patient completed 5 study visits with a 2-week washout period followed by 3 months of treatment. A total of 164 patients from 11 centers completed the study, 95 in the standard arm and 69 in the hemodynamic arm. At baseline and after washout, there were no differences between arms in number of medications or demographic, blood pressure, or hemodynamic characteristics. Systolic blood pressure reductions in the hemodynamic arm were greater from baseline (19 mm Hg versus 11 mm Hg;
P
<0.01) and after washout (25 mm Hg versus 19 mm Hg;
P
<0.05). Diastolic blood pressure reductions were also greater in the hemodynamic arm from baseline (12 mm Hg versus 5 mm Hg;
P
<0.001) and after washout (17 mm Hg versus 10 mm Hg;
P
<0.001). The hemodynamic arm achieved goal blood pressure (<140/90 mm Hg) more frequently (77% versus 57%;
P
<0.01) and a more aggressive blood pressure level (<130/85 mm Hg) more frequently (55% versus 27%;
P
<0.0001). These study results indicate that antihypertensive therapy guided by impedance cardiography in uncontrolled hypertensive patients on ≥1 medications is more effective than standard care.
Impaired Capacity for Stimulated Fibrinolysis in Primary Hypertension Is Restored by Antihypertensive Therapy
Authors: Ridderstråle Wilhelm , Ulfhammer Erik , Jern Sverker , Hrafnkelsdóttir Thórdís
Published: March 2006

The increased risk for myocardial infarction and ischemic stroke in primary hypertension suggests that the condition is associated with prothrombotic mechanisms. We have shown that patients with hypertension have an impaired capacity for acute endothelial tissue-type plasminogen activator (t-PA) release, an important local protective response to prevent formation of intravascular thrombi. The aim of the present study was to investigate whether this impairment could be restored by the lowering of blood pressure. The capacity for acute t-PA release in response to intraarterial infusion of substance P at 8 pmol/min was investigated in a perfused-forearm study in 20 hypertensive patients (12 men and 8 women). Studies were performed when patients were untreated and after 8 weeks of randomized treatment with lisinopril or felodipine that lowered blood pressure by 26/10 and 24/12 mm Hg, respectively. The t-PA release response increased significantly with treatment (ANOVA,
P
=0.0001), with a similar effect in the 2 treatment groups. The peak release of t-PA increased from 257 (58) to 445 (77) ng/min×L/tissue
−1
(
t
test,
P
=0.02). Also, treatment shortened the average time to peak secretion from 6.7 (1.4) to 2.7 (0.3) min (
t
test,
P
=0.01). In 6 patients with a delayed secretory peak (9 minutes or later), treatment normalized the response (χ
2
test,
P
=0.008). Antihypertensive therapy restores the capacity for acute t-PA release and improves the rapidity of the response in patients with primary hypertension. Similar responses with the 2 regimens suggest that the improvement is related to the blood pressure reduction as such. This effect may contribute to the thromboprotective effect of antihypertensive treatment.
Serum Uric Acid Is Associated With Microalbuminuria in Prehypertension
Authors: Lee Jung Eun , Kim Yoon-Goo , Choi Yoon-Ho , Huh Wooseong , Kim Dae Joong , Oh Ha Young
Published: March 2006

Serum uric acid is associated with cardiovascular disease. However, the independent role of uric acid in the development of cardiovascular disease is uncertain. This study examined the cross-sectional association of serum uric acid level with microalbuminuria among 6771 subjects without diabetes or hypertension. Blood pressure was categorized as prehypertension (systolic blood pressure, 120 to 140 mm Hg or diastolic blood pressure, 80 to 90 mm Hg) and normotension (systolic blood pressure, <120 mm Hg and diastolic blood pressure, <80 mm Hg). Microalbuminuria was found in 4.0% of normotensive subjects (n=4819) and in 7.9% of prehypertensive subjects (n=1952). Prehypertensive subjects with microalbuminuria had higher uric acid level than those with normoalbuminuria (men, 387 [68] mmol/L versus 371 [69] mmol/L;
P
=0.017; women 286 [56] mmol/L versus 262 [54] mmol/L;
P
=0.006). However, the difference in serum uric acid level according to the presence or absence of microalbuminuria was not found in the normotensive group. Multiple logistic regression models showed that, in the prehypertensive group, after adjustment for other cardiovascular risk factors, the highest uric acid quartile entailed >2 times greater risk for microalbuminuria than the lowest quartile in both men (odds ratio, 2.12; 95% CI, 1.16 to 3.87) and women (odds ratio, 3.36; 95% CI, 1.17 to 9.69). In the normotensive group, serum uric acid quartile did not show the independent association with microalbuminuria. In conclusion, serum uric acid level was strongly associated with microalbuminuria in prehypertensive subjects.
Role of Circulating Karyocytes in the Initiation and Progression of Atherosclerosis
Authors: Chon Helena , Verhaar Marianne C. , Koomans Hein A. , Joles Jaap A. , Braam Branko
Published: March 2006

Cardiovascular disease is still hard to predict in an individual. The main focus in cardiovascular research has been on endothelial cells and vascular smooth muscle cells of the vessel wall and their interactions with the blood flow. Alterations in the properties of the blood have received a lot of attention in biochemical terms. Interestingly, alterations in the properties of circulating cells have received less attention. We propose that presence of 1 or more risk factors together with normal physiological stimuli induce redox-dependent changes in leukocyte gene transcription with pathophysiological responses. Thus, risk factors render leukocytes hypersensitive to normal stimuli. Risk factors can be subdivided into physical and chemical factors. Superimposed on physiological regulators of leukocyte function, these risk factors promote a cellular pro-oxidative state. Redox-sensitive transcription factors are activated, leading to responses involving inflammation, adhesion, migration, and additional reactive oxygen species generation. As a consequence, monitoring of individual gene expression signatures of these cells could well increase our understanding of the mechanisms by which leukocytes and, in particular, monocytes function. Furthermore, transcriptomes of these cells could be used to investigate the aggressiveness of the atherosclerotic process or to guide treatment in the patient with risk factors for atherosclerosis.
No Evidence of Transdifferentiation of Human Endothelial Progenitor Cells Into Cardiomyocytes After Coculture With Neonatal Rat Cardiomyocytes
Authors: Gruh Ina , Beilner Janina , Blomer Ulrike , Schmiedl Andreas , Schmidt-Richter Ingrid , Kruse Marie-Luise , Haverich Axel , Martin Ulrich
Published: March 2006

Background—

Recent studies have suggested the differentiation of human endothelial progenitor cells (huEPCs) isolated from peripheral blood into cardiomyocytes. This study investigates whether, when cocultured, neonatal rat cardiomyocytes (NRCMs) can induce transdifferentiation of huEPCs into cardiomyocytes.

Methods and Results—

Coculture experiments with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine (DiI)–labeled huEPCs and NRCMs have been performed. Cocultures have been analyzed by means of flow cytometry, 3D confocal laser microscopy, species-specific reverse transcriptase–polymerase chain reaction for the expression of human cardiac marker genes, and electron microscopy. Although fluorescence-activated cell sorting (FACS) analysis and conventional wide-field fluorescence microscopy suggested the existence of DiI
pos
cardiomyocytes in cocultures, no convincing evidence of cardiac differentiation of huEPCs has been obtained. Apparently, DiI
pos
cardiomyocytes were identified as necrotic NRCMs or NRCM-derived vesicles with high levels of autofluorescence or, alternatively, as NRCMs lying on top of or below labeled huEPCs or huEPC fragments. Accordingly, no expression of human Nkx2.5, GATA-4, or cardiac troponin I was detected.

Conclusions—

No convincing evidence of transdifferentiation of huEPCs into cardiomyocytes was obtained. Although we cannot exclude that recent contrary data may be due to slightly different culture protocols, our study has revealed that recently applied standard analysis tools including FACS and wide-field fluorescence microscopy are not sufficient to demonstrate transdifferentiation in coculture settings and can lead to misinterpretation of the data obtained solely with these methods.
Intracoronary Bone Marrow Cell Transfer After Myocardial Infarction
Authors: Meyer Gerd P. , Wollert Kai C. , Lotz Joachim , Steffens Jan , Lippolt Peter , Fichtner Stephanie , Hecker Hartmut , Schaefer Arnd , Arseniev Lubomir , Hertenstein Bernd , Ganser Arnold , Drexler Helmut
Published: March 2006

Background—

Intracoronary transfer of autologous bone marrow cells (BMCs) may enhance recovery of left ventricular (LV) function in patients after acute myocardial infarction (AMI). However, clinical studies addressing the effects of BMCs after AMI have covered only limited time frames ranging from 3 to 6 months. The critical question of whether BMC transfer can have a sustained impact on LV function remains unanswered.

Methods and Results–

After percutaneous coronary intervention with stent implantation (PCI) of the infarct-related artery, 60 patients were randomized 1:1 to a control group with optimal postinfarction therapy and a BMC transfer group that also received an intracoronary BMC infusion 4.8±1.3 days after PCI. Cardiac MRI was performed 3.5±1.5 days, 6±1 months, and 18±6 months after PCI. BMC transfer was not associated with adverse clinical events. In the control group, mean global LV ejection fraction increased by 0.7 and 3.1 percentage points after 6 and 18 months, respectively. LV ejection fraction in the BMC transfer group increased by 6.7 and 5.9 percentage points. The difference in LVEF improvement between groups was significant after 6 months but not after 18 months (
P
=0.27). The speed of LV ejection fraction recovery over the course of 18 months was significantly higher in the BMC transfer group (
P
=0.001).

Conclusions–

In this study, a single dose of intracoronary BMCs did not provide long-term benefit on LV systolic function after AMI compared with a randomized control group; however, the study suggests an acceleration of LV ejection fraction recovery after AMI by BMC therapy.
Advanced Glycation End Products Activate a Chymase-Dependent Angiotensin II–Generating Pathway in Diabetic Complications
Authors: Koka Vijay , Wang Wansheng , Huang Xiao Ru , Kim-Mitsuyama Shokei , Truong Luan D. , Lan Hui Y.
Published: March 2006

Background—

Angiotensin II is a key mediator of diabetes-related vascular disease. It is now recognized that in addition to angiotensin-converting enzyme, chymase is an important alternative angiotensin II–generating enzyme in hypertension and diabetes. However, the mechanism of induction of chymase in diabetes remains unknown.

Methods and Results—

Here, we report that chymase is upregulated in coronary and renal arteries in patients with diabetes by immunohistochemistry. Upregulation of vascular chymase is associated with deposition of advanced glycation end products (AGEs), an increase in expression of the receptor for AGEs (RAGE), and activation of ERK1/2 MAP kinase. In vitro, AGEs can induce chymase expression and chymase-dependent angiotensin II generation in human vascular smooth muscle cells via the RAGE-ERK1/2 MAP kinase–dependent mechanism. This is confirmed by blockade of AGE-induced vascular chymase expression with a neutralizing RAGE antibody and an inhibitor to ERK1/2 and by overexpression of the dominant negative ERK1/2. Compared with angiotensin-converting enzyme, chymase contributes to the majority of angiotensin II production (>70%,
P
<0.01) in response to AGEs. Furthermore, AGE-induced angiotensin II production is blocked by the anti-RAGE antibody and by inhibition of ERK1/2 MAP kinase activities.

Conclusions—

AGEs, a hallmark of diabetes, induce chymase via the RAGE-ERK1/2 MAP kinase pathway. Chymase initiates an important alternative angiotensin II–generating pathway in diabetes and may play a critical role in diabetic vascular disease.
Radiation Dose Estimates From Cardiac Multislice Computed Tomography in Daily Practice
Authors: Hausleiter Jörg , Meyer Tanja , Hadamitzky Martin , Huber Ester , Zankl Maria , Martinoff Stefan , Kastrati Adnan , Schömig Albert
Published: March 2006

Background—

Multislice computed tomography angiography (CTA) is a promising technology for imaging patients with suspected coronary artery disease. Compared with 16-slice CTA, the improved spatial and temporal resolution of 64-slice CTA (0.6- versus 1.0-mm slice thickness and 330- versus 420-ms gantry rotation time) is associated with an increase in radiation dose. The objective of this retrospective investigation was to compare the estimated dose received during 16- and 64-slice CTA in daily practice and to investigate the impact of different scan protocols on dose and image quality.

Methods and Results—

Radiation dose was estimated for 1035 patients undergoing coronary CTA. Scanning algorithms with and without an ECG-dependent dose modulation and with a reduced tube voltage were investigated on dose estimates and image quality. In the entire patient cohort, radiation dose estimates were 6.4±1.9 and 11.0±4.1 mSv for 16- and 64-slice CTA, respectively (
P
<0.01). The reduction in radiation dose estimates ranged between 37% and 40% and between 53% and 64% with the use of ECG-dependent dose modulation and with the combined use of the dose modulation and a reduced tube voltage, respectively. The reduction in dose estimates was not associated with a reduction in diagnostic image quality as assessed by the signal-to-noise ratio and by the frequency of coronary segments with diagnostic image quality.

Conclusions—

The increase in spatial and temporal resolution with 64-slice CTA is associated with an increased radiation dose for coronary CTA. Dose-saving algorithms are very effective in reducing radiation exposure and should be used whenever possible.
Foxes, Hounds, and Horses: Who or Which?
Authors: Gupta Anthea Fraser
Published: March 2006

Writers of English can choose whether to mark a high level of sentience in a nonhuman animal by selecting the word who rather than which. An examination of texts relating to foxhunting on the world wide web showed that, in reference to the nonhuman animals involved in foxhunting, writers were most likely to use who in reference to foxes, and least likely to use it in reference to horses. Those who support foxhunting are more likely to recognize the sentience of the fox than those who oppose foxhunting. This may be because those who enjoy foxhunting present the fox as an active creator of the hunt, and as a worthy opponent.
Animals and the Discourse of Farming in Southern Africa
Authors: Mitchell Les
Published: March 2006

This paper looks at discourses related to animal farming in a popular South African farming magazine. The paper analyzes four ar ticles using a form of Critical Discourse Analysis (CDA). Despite varying widely in content and style, all articles draw from the discourses of production and science; two also show a minor discourse of achievement. With further work, it is possible to discern a fourth, deeply embedded discourse: that of enslavement. This also was present in all the articles. These discourses objectify nonhuman animals and support a world-view of teleological anthropocentrism that fits well with present capitalist practices.
Humans, Animals, and Metaphors
Authors: Goatly Andrew
Published: March 2006

This article examines the ideological implications of different interpretations of the statement "Humans are animals." It contrasts theories that regard humans as literally sophisticated animals with those who interpret the statement metaphorically. Sociobiological theories, bolstered by metaphors in the dictionary of English emphasize competitiveness and aggression as features shared by humans and nonhuman animals. Other theories emphasize symbiosis and cooperation. Some of these theories are prescriptive—metaphor patterns in English reflect the strong tendency to regard animal behavior as something for humans to avoid. Conversely, sociobiologists suggest it is natural and right to behave like animals, the naturalistic fallacy. Other cultural theories suggest that the statement is only metaphorical; our differences from animals are what make us most human. The article notes the tendency to metaphorically project the values and structures of current human society onto the animals being studied, serving the interest of those who, in power, benefit from the status quo.
Deep Ecology and Language: The Curtailed Journey of the Atlantic Salmon
Authors: Stibbe Arran
Published: March 2006

This article explores the representation of fish in ecological discourse through analysis of the recently published Millennium Ecosystem Assessment (MA, 2005) synthesis report. The analysis utilizes an ecological framework based on "deep ecology" (Naess, 1990), examining how the discourse of the MA asserts or denies the intrinsic worth of fish. The discursive construction of fish is particularly relevant given the massive expansion of the aquaculture industry, which is having a negative impact on ecosystems and the fish themselves, particularly the Atlantic salmon. There are alternatives to traditional ecological discourses, such as the lyrical discourse drawn on by Rachel Carson (1962) in her description of salmon. The article concludes with a discussion of the potential of such discourses to represent reality in ways that are more comparable with the welfare of the fish and the protection of ecosystems.
Verbal Activism: "Anymal"
Authors: Kemmerer Lisa
Published: March 2006

This paper is an exploration of verbal activism and animal liberation, starting with a brief explanation of Wittgenstein's (1953) views on the nature and role of language. A discussion of lexical gaps, linguistic change, and verbal activism follows: The paper introduces the word, "anymal," to fill a lexical gap and to provide a form of verbal activism.
Manichaeism and Ancient Mesopotamian "Gnosticism"
Authors: Ataç Mehmet-Ali
Published: March 2006

This essay compares Manichaean cosmogony with select ancient Mesopotamian myths with special emphasis on parallels between the Manichaean "First Creation" and the myth of the Descent of Inanna/Ishtar to the netherworld. It further compares the Manichaean "Second Creation" and "Third Creation" with aspects of the Babylonian Poem of Creation, Enuma Elish, and The Epic of Gilgamesh respectively. Unlike Gnostic myths, no overall semantic network seems to tie individual Mesopotamian myths together. However, close correspondence between both traditions not only helps one see certain Mesopotamian myths in a different light, but also reveals the indebtedness of Gnostic myths to Near Eastern antiquity.
Broadband Albedo Observations in the Southern Great Plains
Authors: Duchon Claude E. , Hamm Kenneth G.
Published: March 2006

Time series of daily broadband surface albedo for 1998 and 1999 have been analyzed from six locations in the network of 22 Atmospheric Radiation Measurement Program Solar–Infrared Radiation Stations distributed from central Kansas to central Oklahoma. Two of the stations are in Kansas, and four are in Oklahoma; together they reasonably encompass the variation in geography in the southern Great Plains. Daily precipitation totals locally measured or obtained from nearby Oklahoma Mesonet stations and time series of biweekly maximum normalized difference vegetation index obtained from NOAA’s Advanced Very High Resolution Radiometer were used to determine linkages between surface albedo and amount of precipitation and degree of green vegetation. As part of this determination, daily albedo was categorized according to sky condition, that is, clear, partly cloudy, or overcast, with appropriate boundaries for each category. The more notable results are the following: 1) 2-yr mean annual albedos varied by more than 20% among the six sites, the lowest albedo being 0.18 and the highest albedo being 0.22; 2) the numerical difference was about 4 times the maximum interannual mean difference among the six stations, indicating the importance of geographic location; 3) for sites with a large amount of bare soil, a systematic decrease in albedo in response to rainfall events and a systematic increase in albedo as the soil dried were observed; 4) at the one site with total vegetation cover, that is, no bare soil, albedo response to precipitation events was suppressed; 5) no relation was found between mean annual albedo and annual precipitation; 6) whether days were classified as clear or partly cloudy had little influence on daily albedo, but overcast days typically reduced albedo, sometimes substantially; and 7) the main contributor to low albedos on overcast days with rain was the wet surface; the contribution by the overcast sky was secondary.
High-Resolution Large-Eddy Simulations of Flow in a Steep Alpine Valley. Part I: Methodology, Verification, and Sensitivity Experiments
Authors: Chow Fotini Katopodes , Weigel Andreas P. , Street Robert L. , Rotach Mathias W. , Xue Ming
Published: March 2006

This paper investigates the steps necessary to achieve accurate simulations of flow over steep, mountainous terrain. Large-eddy simulations of flow in the Riviera Valley in the southern Swiss Alps are performed at horizontal resolutions as fine as 150 m using the Advanced Regional Prediction System. Comparisons are made with surface station and radiosonde measurements from the Mesoscale Alpine Programme (MAP)-Riviera project field campaign of 1999. Excellent agreement between simulations and observations is obtained, but only when high-resolution surface datasets are used and the nested grid configurations are carefully chosen. Simply increasing spatial resolution without incorporating improved surface data gives unsatisfactory results. The sensitivity of the results to initial soil moisture, land use data, grid resolution, topographic shading, and turbulence models is explored. Even with strong thermal forcing, the onset and magnitude of the upvalley winds are highly sensitive to surface processes in areas that are well outside the high-resolution domain. In particular, the soil moisture initialization on the 1-km grid is found to be crucial to the success of the finer-resolution predictions. High-resolution soil moisture and land use data on the 350-m-resolution grid also improve results. The use of topographic shading improves radiation curves during sunrise and sunset, but the effects on the overall flow are limited because of the strong lateral boundary forcing from the 1-km grid where terrain slopes are not well resolved. The influence of the turbulence closure is also limited because of strong lateral forcing and hence limited residence time of air inside the valley and because of the stable stratification, which limits turbulent stress to the lowest few hundred meters near the surface.
High-Resolution Large-Eddy Simulations of Flow in a Steep Alpine Valley. Part II: Flow Structure and Heat Budgets
Authors: Weigel Andreas P. , Chow Fotini K. , Rotach Mathias W. , Street Robert L. , Xue Ming
Published: March 2006

This paper analyzes the three-dimensional flow structure and the heat budget in a typical medium-sized and steep Alpine valley—the Riviera Valley in southern Switzerland. Aircraft measurements from the Mesoscale Alpine Programme (MAP)-Riviera field campaign reveal a very pronounced valley-wind system, including a strong curvature-induced secondary circulation in the southern valley entrance region. Accompanying radio soundings show that the growth of a well-mixed layer is suppressed, even under convective conditions. Our analyses are based on the MAP-Riviera measurement data and the output of high-resolution large-eddy simulations using the Advanced Regional Prediction System (ARPS). Three sunny days of the measurement campaign are simulated. Using horizontal grid spacings of 350 and 150 m (with a vertical spacing as fine as 20 m), the model reproduces the observed flow features very well. The ARPS output data are then used to calculate the components of the heat budget of the valley atmosphere, first in profiles over the valley base and then as averages over almost the entire valley volume. The analysis shows that the suppressed growth of the well-mixed layer is due to the combined effect of cold-air advection in the along-valley direction and subsidence of warm air from the free atmosphere aloft. It is further influenced by the local cross-valley circulation. This had already been hypothesized on the basis of measurement data and is now confirmed through a numerical model. Averaged over the entire valley, subsidence turns out to be one of the main heating sources of the valley atmosphere and is of comparable magnitude to turbulent heat flux divergence. On the mornings of two out of the three simulation days, this subsidence is even identified as the only major heating source and thus appears to be an important driving mechanism for the onset of thermally driven upvalley winds.
Mapping the Hazard of Extreme Rainfall by Peaks over Threshold Extreme Value Analysis and Spatial Regression Techniques
Authors: Beguería Santiago , Vicente-Serrano Sergio M.
Published: March 2006

The occurrence of rainfalls of high magnitude constitutes a primary natural hazard in many parts of the world, and the elaboration of maps showing the hazard of extreme rainfalls has great theoretical and practical interest. In this work a procedure based on extreme value analysis and spatial interpolation techniques is described. The result is a probability model in which the distribution parameters vary smoothly in space. This methodology is applied to the middle Ebro Valley (Spain), a climatically complex area with great contrasts because of the relief and exposure to different air masses. The database consists of 43 daily precipitation series from 1950 to 2000. Because rainfall tends to occur highly clustered in time in the area, a declustering process was applied to the data, and the series of daily cluster maxima were used hereinafter. The mean excess plot and error minimizing were used to find an optimum threshold value to retain the highest records (peaks-over-threshold approach), and a Poisson–generalized Pareto model was fitted to the resulting series. The at-site parameter estimates (location, scale, and shape) were regressed upon a set of location and relief variables, enabling the construction of a spatially explicit probability model. The advantages of this method to obtain maps of extreme precipitation hazard are discussed in depth.
Contrails to Cirrus—Morphology, Microphysics, and Radiative Properties
Authors: Atlas David , Wang Zhien , Duda David P.
Published: March 2006

This work is two pronged, discussing 1) the morphology of contrails and their transition to cirrus uncinus, and 2) their microphysical and radiative properties. It is based upon the fortuitous occurrence of an unusual set of essentially parallel contrails and the unanticipated availability of nearly simultaneous observations by photography, satellite, automated ground-based lidar, and a newly available database of aircraft flight tracks. The contrails, oriented from the northeast to southwest, are carried to the southeast with a component of the wind so that they are spread from the northwest to southeast. Convective turrets form along each contrail to form the cirrus uncinus with fallstreaks of ice crystals that are oriented essentially normal to the contrail length. Each contrail is observed sequentially by the lidar and tracked backward to the time and position of the originating aircraft track with the appropriate component of the wind. The correlation coefficient between predicted and actual time of arrival at the lidar is 0.99, so that one may identify both visually and satellite-observed contrails exactly. Contrails generated earlier in the westernmost flight corridor occasionally arrive simultaneously with those formed later closer to the lidar to produce broader cirrus fallstreaks and overlapping contrails on the satellite image. The minimum age of a contrail is >2 h and corresponds to the longest time of travel to the lidar. The lag between the initial formation of the contrail and its first detectability by Moderate-Resolution Imaging Spectroradiometer (MODIS) is ≈33 min, thus accounting for the distance between the aircraft track and the first detectable contrail by satellite. The lidar also provides particle fall speeds and estimated sizes, optical extinction coefficients, optical thickness (τ = 0.35), and ice water path (IWP = 8.1 g m−2). These values correspond to the lower range of those found for midlatitude cirrus by Heymsfield et al. The ice water per meter of length along the cloud lines is 103–104 times that released by typical jet aircraft. The synthesis of these findings with those of prior investigators provides confidence in the present results. Various authors find that contrail-generated cirrus such as reported here contribute to net regional warming.
Objective Assessment of the Information Content of Visible and Infrared Radiance Measurements for Cloud Microphysical Property Retrievals over the Global Oceans. Part I: Liquid Clouds
Authors: L’Ecuyer Tristan S. , Gabriel Philip , Leesman Kyle , Cooper Steven J. , Stephens Graeme L.
Published: March 2006

The importance of accurately representing the role of clouds in climate change studies has become increasingly apparent in recent years, leading to a substantial increase in the number of satellite sensors and associated algorithms that are devoted to measuring the global distribution of cloud properties. The physics governing the radiative transfer through clouds is well understood, but the impact of uncertainties in algorithm assumptions and the true information content of the measurements in the inverse retrieval problem are generally not as clear, making it difficult to determine the best product to adopt for any particular application. This paper applies information theory to objectively analyze the problem of liquid cloud retrievals from an observing system modeled after the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument currently operating on the Aqua and Terra platforms. It is found that four diagnostics—the retrieval error covariance, the information content, the number of degrees of freedom for signal, and the effective rank of the problem—provide a rigorous test of an observing system. Based on these diagnostics, the combination of the 0.64- and 1.64-μm channels during the daytime and the 3.75- and 11.0-μm channels at night provides the most information for retrieving the properties of the wide variety of liquid clouds modeled. With an eye toward developing a coherent representation of the global distribution of cloud microphysical and radiative properties, these four channels may be integrated into a suitable multichannel inversion methodology such as the optimal estimation or Bayesian techniques to provide a common framework for cloud retrievals under varying conditions. The expected resolution of the observing system for such liquid cloud microphysical property retrievals over a wide variety of liquid cloud is also explored.