bluuebunny/crossref_metadata_2025 huggingface dataset:
Genomic analysis reveals poor separation of human cardiomyopathies of ischemic and nonischemic etiologies
Authors: Kuner Ruprecht , Barth Andreas S. , Ruschhaupt Markus , Buness Andreas , Zwermann Ludwig , Kreuzer Eckart , Steinbeck Gerhard , Poustka Annemarie , Sültmann Holger , Nabauer Michael
Published: April 2008

Clinically, the differentiation between ischemic (ICM) and nonischemic (NICM) human cardiomyopathies is highly relevant, because ICM and NICM differ with respect to prognosis and certain aspects of pharmacological therapy, despite a common final phenotype characterized by ventricular dilatation and reduced contractility. So far, it is unclear whether microarray-based signatures can be used to infer the etiology of heart failure. Using three different classification algorithms, we independently analyzed one cDNA and two publicly available high-density oligonucleotide microarray studies comprising a total of 279 end-stage human heart failure samples. When classifiers identified in a single study were applied to the remaining studies, misclassification rates >25% for ICM and NICM specimens were noted, indicating poor separation of both etiologies. However, data mining of 458 classifier genes that were concordantly identified in at least two of the three data sets points to different biological processes in ICM vs. NICM. Consistent with the underlying ischemia, cytokine signaling pathways and immediate-early response genes were overrepresented in ICM samples, whereas NICM samples displayed a deregulation of cytoskeletal transcripts, genes encoding for the major histocompatibility complex, and antigen processing and presentation pathways, potentially pointing to immunologic processes in NICM. Overall, our results suggest that ICM and NICM exhibit substantial heterogeneity at the transcriptomic level. Prospective studies are required to test whether etiology-specific gene expression patterns are present at earlier disease stages or in subsets of both etiologies.
Intestine: Organ or Apparatus?
Authors: Gasbarrini Giovanni , Montalto Massimo , Santoro Luca , Curigliano Valentina , D’Onofrio Ferruccio , Gallo Antonella , Visca Dina , Gasbarrini Antonio
Published: April 2008

It is well known that human intestine is involved in different important functions. First of all, it is responsible for digestion and absorption of nutrients, electrolytes, water, bile salts and drugs, but it also has immunologic, endocrine and motor functions. Moreover, intestinal microflora, composed by a large diversity of bacterial cells, provides several beneficial functions for the host and is, nowadays, defined by many authors as an organ itself. In consideration of intestine complexity, we tried to understand if it can be considered only an organ or if it is an apparatus itself. We have analyzed the different components and their relationships, showing that a continuous collaboration is required among enterocytes, endocrine intestinal cells, gut immune system and microflora to assure an efficient mechanism of defense. In consideration of the complexity of intestinal components, together with the emergent role of microflora, we think that we could start to consider gut as a real apparatus, and not only as an organ.
Celiac Disease: What’s New about It?
Authors: Gasbarrini Giovanni , Malandrino Noemi , Giorgio Valentina , Fundarò Carlo , Cammarota Giovanni , Merra Giuseppe , Roccarina Davide , Gasbarrini Antonio , Capristo Esmeralda
Published: April 2008

In the present review we will try to summarize the clinical and diagnostic features of celiac disease (CD) as well as the new findings on extraintestinal manifestation. CD is an immune-mediated enteropathy caused by a permanent gluten intolerance. In the last years, the diagnosis is becoming more and more frequent because of the recognition of ‘new’ symptoms and associated extraintestinal manifestations. Classical CD is dominated by symptoms and sequelae of gastrointestinal malabsorption. In the ‘atypical forms’, the extraintestinal features usually predominate, with few or no gastrointestinal symptoms. Silent CD refers to asymptomatic patients with a positive serologic test and villous atrophy on biopsy. This form is detected by screening of high-risk individuals, or villous atrophy occasionally may be detected by endoscopy and biopsy conducted for another reason. The potential form is diagnosed in groups at risk including relatives of celiac patients, Down syndrome and autoimmune diseases. Latent CD is defined by positive serological tests but not histological changes on biopsy. These individuals are asymptomatic, but later may develop symptoms and/or histological alterations. Recognition of atypical manifestations of CD is very important because many cases can remain undiagnosed with an increased risk of long-term complications.
Metabolic and Nutritional Features in Adult Celiac Patients
Authors: Malandrino Noemi , Capristo Esmeralda , Farnetti Sara , Leggio Lorenzo , Abenavoli Ludovico , Addolorato Giovanni , Gasbarrini Giovanni
Published: April 2008

Celiac disease (CD) is a chronic immune-mediated gluten-dependent enteropathy induced by ingestion of gluten-containing products, characterized by intestinal malabsorption and subtotal or total atrophy of intestinal villi, which improves after gluten-free diet (GFD). Untreated patients affected by the classic form of CD are at high risk of malnutrition, but an impairment of nutritional status is frequently reported also in patients with the subclinical form of the disease. Strict adherence to a GFD greatly improves nutritional status, inducing an increase in fat and bone compartments, but does not completely normalize body composition. A lack of improvement in nutritional status may identify incomplete adherence to GFD treatment. Evidence has shown lower body weights and lower fat mass and fat-free mass contents in CD patients. Untreated CD patients oxidize more carbohydrates as energy substrate compared to treated subjects. In addition, circulating ghrelin concentration was reduced after GFD treatment as a possible consequence of body composition improvement, while leptin did not correlate with the changes in body composition and substrate oxidation in patients with CD. A significant correlation was reported between ghrelin and the degree of severity of intestinal mucosal lesions. CD patients might show an alteration in lipid metabolism, i.e. low serum total and high- density lipoprotein-cholesterol as a consequence of lipid malabsorption and decreased intake. In conclusion, weight loss and nutritional deficiencies are relevant clinical features in CD. Thus, an early and accurate evaluation of nutritional status and energy metabolism represents a fundamental tool in the management of CD patients.
Vascular Involvement in Inflammatory Bowel Disease: Pathogenesis and Clinical Aspects
Authors: Papa Alfredo , Scaldaferri Franco , Danese Silvio , Guglielmo Simona , Roberto Italia , Bonizzi Michele , Mocci Giammarco , Felice Carla , Ricci Caterina , Andrisani Gianluca , Fedeli Giuseppe , Gasbarrini Giovanni , Gasbarrini Antonio
Published: April 2008

Crohn’s disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel disease (IBD), are chronic inflammatory conditions, characterized by a microvascular and also macrovascular involvement. Chronically inflamed intestinal microvessels of IBD patients have demonstrated significant alterations in their physiology and function compared with vessels from healthy and uninvolved IBD intestine. Recently, some studies have revealed that the poor mucosal healing, refractory inflammatory ulcerations and damage in the IBD intestine could depend on microvascular dysfunction, resulting in diminished vasodilatory capacity and tissue hypoperfusion in the IBD gut. Furthermore, several data show that the activation of intestinal endothelium plays a critical role in the pathogenesis and/or in perpetuating and amplifying the inflammatory process in IBD and, consequently, it is now emerging as a potential use of anticoagulant or coagulation-related drugs in treating IBD. IBD is also associated with an increased risk of macrovascular venous and arterial thrombosis. Thrombotic events occur prevalently as deep vein thrombosis and pulmonary embolism. They happen at an earlier age than in non-IBD patients. Prothrombotic risk factors in IBD patients could be distinguished as acquired, such as active inflammation, immobility, surgery, steroid therapy, and use of central venous catheters, and inherited. Furthermore, it has been found that IBD, per se, is an independent risk factor for thrombosis. The prevention of thromboembolic events in IBD patients includes the elimination of removable risk factors and, if thrombosis occurs, a pharmacological therapy similar to that used for thromboembolic events occurring in the general population.
The Regulation of Mesangial Cell Proliferation
Authors: Cove-Smith Andrea , Hendry Bruce M.
Published: April 2008

Mesangial cell (MC) proliferation is a key pathological feature in a number of common human renal diseases including IgA, systemic lupus erythematosus and diabetic nephropathies. Knowledge of the role of MCs in normal glomeruli and of their response to pathological stimuli is crucial to the understanding of these disease processes. The purpose of understanding disease is ultimately to develop therapeutic strategies that can limit or even reverse the underlying pathological process. Over the last 20 years a number of signaling pathways involved in the regulation of MC proliferation have been identified and studied with a view to manipulating them for therapeutic gain. Unfortunately, despite these advances, there are still very few clinical options that specifically target aberrant MC proliferation. This article reviews a number of factors that have been shown to play a role in controlling MC proliferation, including signaling molecules (e.g. Platelet-derived growth factor, Ras and Ca2+), cell cycle proteins (e.g. cyclin D1) and transcription factors (E2F). A variety of strategies has been used to manipulate these different pathways to elucidate their function in MCs with the ultimate aim of modifying them in order to treat human renal diseases.
Lack of a Significant Effect of Cannabinoids upon the Uptake of 2-Deoxy-D-Glucose by Caco-2 Cells
Authors: Gonçalves Pedro , Araújo João Ricardo , Azevedo Isabel , Martel Fátima
Published: April 2008

The endogenous cannabinoid system plays a role in the regulation of energy homeostasis acting through central pathways, and its dysregulation may be implicated in the pathogenesis of obesity. Recent evidence is accumulating showing that the endogenous cannabinoid system is also present in peripheral tissues. The aim of this work was to investigate the effect of cannabinoids upon the intestinal absorption of glucose. For this, we investigated the effect of some cannabinoid receptor agonists and antagonists upon the apical uptake of 3H-2-deoxy-D-glucose by the human intestinal epithelial Caco-2 cells. Uptake of a low concentration of 3H-2-deoxy-D-glucose (1 µmol/l) was both cytochalasin B- and phloridzin-sensitive. The maximal inhibition obtained with each of these inhibitors was 50%, and their effect was not cumulative. On the other hand, uptake of a high concentration of 3H-2-deoxy-D-glucose (20 mmol/l) was partially inhibited by cytochalasin B (±20%) and phloridzin had no effect. We verified that neither the cannabinoid receptor agonists [tetrahydrocannabinol (1–10 µmol/l), anandamide (0.1–10 µmol/l) and CP 55,940 (5 nmol/l to 1 µmol/l)], nor the specific CB1 and CB2 antagonists [AM251 (10–500 nmol/l) and AM630 (50 nmol/l to 1 µmol/l), respectively] had a significant effect upon 3H-2-deoxy-D-glucose uptake by Caco-2 cells. This was true for both the uptake of a low (1 µmol/l) and of a high (20 mmol/l) concentration of 3H-2-deoxy-D-glucose. From these results, we may hypothesize that cannabinoids do not interfere with the intestinal GLUT2-mediated apical uptake of glucose.
Dietary Nutrients and Insulin Resistance in Urban Asian Indian Adolescents and Young Adults
Authors: Isharwal Sumit , Arya Shipra , Misra Anoop , Wasir Jasjeet S. , Pandey Ravindra M. , Rastogi Kavita , Vikram Naval K. , Luthra Kalpana , Sharma Rekha
Published: April 2008

Background: Asian Indians have a high prevalence of insulin resistance that may underlie their higher tendency to develop type 2 diabetes mellitus and early-onset atherosclerosis. Objective: To investigate the relationship between dietary nutrients and insulin resistance in Asian Indian adolescents and young adults. Design: Dietary nutrient intake values (24-hour dietary recall and monthly consumption data) and fasting serum insulin levels were studied in 352 (311 males and 41 females) healthy adolescents and young adults (mean age 18.0 ± 2.3 years; range 14–25 years). Bivariate and multivariate logistic regression analyses were performed with hyperinsulinemia as the outcome variable and various dietary nutrients and anthropometric variables as covariates. Results: Mean fasting serum insulin levels were 107.4 ± 35.0 pmol/l (36.5–230.4 pmol/l). The intake of polyunsaturated fatty acids (PUFAs) was higher, saturated fat and the ω–6 to ω–3 PUFA ratio were in the upper limit, and ω–3 PUFAs (% caloric intake, En) were lower than the recommended dietary allowance for Asian Indians. The PUFAs (% En), BMI, percent body fat and waist circumference were significantly higher in the hyperinsulinemic group compared with the normoinsulinemic group (p = 0.021, 0.0021, 0.0006, and 0.0041, respectively). Multiple regression analysis showed that the lowest tertile of ω–6 (<3% En) PUFA intake [adjusted OR (95% CI) = 0.3 (0.1–0.7)] and BMI [adjusted OR (95% CI) = 2.9 (1.4–6.0)] were the significant independent predictors of fasting hyperinsulinemia. Conclusion: For prevention and amelioration of insulin resistance in Asian Indian adolescents and young adults, it is prudent to have normal BMI and low intake of ω–6 PUFAs.
Variants of Parvovirus B19: Bioinformatical Evaluation of Nested PCR Assays
Authors: Bergallo Massimiliano , Costa Cristina , Sidoti Francesca , Novelli Mauro , Ponti Renata , Castagnoli Carlotta , Merlino Chiara , Bernengo Maria Grazia , Cavallo Rossana
Published: April 2008

Variants of parvovirus B19 are currently grouped into three genotypes: 1 (reference B19 strains), 2 and 3. It has been evidenced that isolate K71 of genotype 2 is more prevalent in skin than the conventional B19 genotype 1. In this study we investigated the detection of parvovirus B19 genotypes by using two nested PCRs and evaluating the suitability of these assays by BLAST search of parvovirus isolates. Subsequently, we analyze the present genotypes in skin biopsies. The two nested PCRs employed in this study allow to amplify 41 isolates as confirmed by bioinformatical validation. The molecular epidemiological characterization of our casistics confirmed the presence of isolate K71 in human skin.
Prolonged Endoplasmic Reticulum Stress Induces Apoptotic Cell Death in an Experimental Model of Chronic Cyclosporine Nephropathy
Authors: Han Sang Woo , Li Can , Ahn Kyung Ohk , Lim Sun Woo , Song Hyun Guk , Jang Yoon Sung , Cho Yoon Mi , Jang Young Min , Ghee Jung Yeon , Kim Jin Young , Kim Su Hyun , Kim Jin , Kwon Oh Joo , Yang Chul Woo
Published: April 2008

Background/Aims: Apoptosis contributes to cyclosporine (CsA)-induced renal cell death. This study tested the effects of CsA-induced endoplasmic reticulum (ER) stress on apoptotic cell death in an experimental model of chronic CsA nephropathy. Methods: CsA (15 mg/kg per day) was given to rats for 7 or 28 days. The ER stress response was evaluated with BiP expression, and the proapoptotic response was assessed with CHOP and caspase 12 expression. ER structure was evaluated by transmission electron microscopy, and apoptotic cell death was detected with TUNEL staining. Results: Short-term treatment of CsA for 7 days activated both the ER stress response (induction of BiP mRNA and protein) and the proapoptotic response (upregulation of caspase 12 and CHOP mRNAs and proteins). However, long-term treatment with CsA for 28 days decreased BiP and further increased CHOP. The imbalance between the two responses coincided with the timing of the appearance of apoptotic cell death and the disruption of the ER structure. Conclusion: Prolonged CsA-induced ER stress causes apoptotic cell death by depleting molecular chaperones and activating the proapoptotic pathway.
Altered Transforming Growth Factor-Beta Signaling in a Murine Model of Thoracic Aortic Aneurysm
Authors: Jones Jeffrey A. , Barbour John R. , Stroud Robert E. , Bouges Shenikqua , Stephens Shelly L. , Spinale Francis G. , Ikonomidis John S.
Published: April 2008

Objective: Thoracic aortic aneurysms (TAAs) develop by a multifactorial process involving maladaptive signaling pathways that alter the aortic vascular environment. Transforming growth factor-beta (TGF-β) has been implicated in regulating the structure and composition of the extracellular matrix by differential activation of various intracellular signaling pathways. However, whether and to what degree TGF-β signaling contributes to TAA development remains unclear. Accordingly, the hypothesis that alterations in TGF-β signaling occur during aneurysm formation was tested in a murine model of TAA. Methods: TAAs were surgically induced in mice (C57BL/6J) and aortas were analyzed at predetermined time points (1, 2, and 4 weeks post-TAA induction). Quantitative real-time PCR (QPCR) was performed to evaluate the expression of 84 relevant TGF-β superfamily genes, and the protein levels of key signaling intermediates were measured by immunoblotting. Results were compared to unoperated reference control mice. Results: QPCR revealed increased expression of TGF-β superfamily ligands (Gdf-2, -6, -7, Inhba), ligand inhibitors (Bmper, Chrd, Gsc), and transcriptional regulators (Dlx2, Evi1), among other genes (Cdkn2b, Igf1, IL-6). Protein levels of TGF-β receptorII, Smad2, Smad1/5/8, phospho-Smad1/5/8, and Smurf1 were increased from control values post-TAA induction. Both TGF-β receptorI and Smad4 were decreased from control values, while ALK-1 levels remained unchanged. Conclusions: These alterations in the TGF-β pathway suggest a mechanism by which primary signaling is switched from a TGF-βRI/Smad2-dependent response, to an ALK-1/Smad1/5/8 response, representing a significant change in signaling outcome, which may enhance matrix degradation.
Efficacy and Tolerability of Rosuvastatin and Atorvastatin when Force-Titrated in Patients with Primary Hypercholesterolemia
Authors: Faergeman Ole , Hill Laurie , Windler Eberhard , Wiklund Olov , Asmar Roland , Duffield Emma , Sosef Froukje
Published: April 2008

Background: Patients at high risk of cardiovascular disease frequently fail to reach recommended low-density lipoprotein cholesterol (LDL-C) goals, partly because statin doses are not titrated to optimal effect. The ECLIPSE study was designed to compare the efficacy and safety of force-titrated treatment with rosuvastatin (10–40 mg) with that of atorvastatin (10–80 mg) in high-risk patients with hypercholesterolemia. Methods: In this 24-week, open-label, randomized, multinational, parallel-group study, 1,036 patients were randomized to rosuvastatin (n = 522) or atorvastatin (n = 514). Results: At all time points, a significantly greater percentage of patients on rosuvastatin treatment achieved the NCEP ATP III LDL-C goal of <100 mg/dl (2.5 mmol/l), the 2003 European LDL-C target of <2.5 or 3.0 mmol/l (100 or 115 mg/dl) and the LDL-C goal of <70 mg/dl (1.8 mmol/l), a goal suggested for very high-risk patients (p < 0.001 for all). Rosuvastatin also achieved significantly greater improvements in components of the atherogenic lipid profile versus atorvastatin. Both treatments were well tolerated. Conclusion: Rosuvastatin titrated across its recommended dose range provides a more favorable effect on lipoprotein variables than atorvastatin, enabling more high-risk patients to achieve recommended LDL-C goals.
Unsuccessful Induction of Endometriosis in Female Rhesus Macaques (Macaca mulatta)
Authors: Defrère Sylvie , Squifflet Jean , Lousse Jean-Christophe , Van Langendonckt Anne , González-Ramos Reinaldo , Foidart Jean-Michel , Jérome Christine , Delattre Luc , Donnez Jacques , Dehoux Jean-Paul
Published: April 2008

Background/Aims: The aim of this study was to induce endometriosis in female rhesus macaques (Macaca mulatta) for research purposes. Methods: Three female monkeys from 4 to 4.5 years of age underwent three consecutive attempts at endometriosis induction over an 8-month period: (i) the first attempt involved intravaginal sampling of endometrial tissue and transplantation into the intrapelvic cavity; (ii) the second entailed surgical removal of endometrium after hysterotomy and intra-abdominal placement, and (iii) the third used endometrial mucosa obtained by scraping the uterus after hysterectomy, placed in a surgical pouch created in the retrovesical space (Retzius). In each case, the pelvic cavity was closely inspected after 7, 9, and 6 weeks respectively for the presence of endometriotic lesions, and peritoneal biopsies were performed. Results: Neither macroscopic observation nor histological analysis revealed any endometriotic lesions. Conclusion: This failure to induce endometriosis in female rhesus macaques suggests that this species is not the most efficient experimental model among primates to investigate endometriosis development or treatment.
Validation of the Voice Handicap Index by Assessing Equivalence of European Translations
Authors: Verdonck-de Leeuw I.M. , Kuik D.J. , De Bodt M. , Guimaraes I. , Holmberg E.B. , Nawka T. , Rosen C.A. , Schindler A. , Whurr R. , Woisard V.
Published: April 2008

Objective: We aimed to assess the equivalence of translations of the Voice Handicap Index (VHI). Patients and Methods: Confirmatory factor analysis was used to assess equivalence of the US version and several translations including (1) Dutch, (2) Flemish Dutch (Belgium), (3) UK English, (4) French, (5) German, (6) Italian, (7) Portuguese and (8) Swedish. VHI questionnaires were gathered from 1,281 subjects. Patients were classified into 11 voice lesion categories. Patients with incomplete response (4%) and patients within voice lesion categories with small numbers were excluded from further analyses, leaving a cohort of 1,052 patients from 8 countries. Results: The internal consistency of the VHI proved to be good. Confirmatory factor analysis across countries revealed that a 3-factor fixed measurement model best fitted the data; the 3 subscales appeared to highly intercorrelated, especially in the US data. The underlying structure of the VHI was also equivalent regarding various voice lesions, but distinct groups were recognized with respect to the height of the VHI scores, indicating that various voice lesions lead to a diversity of voice problems in daily life. Conclusion: The US VHI and the translations appeared to be equivalent, which means that the results from studies from the various included countries can be compared.
The Relationship between the Southern Hemisphere Annular Mode and Antarctic Peninsula Summer Temperatures: Analysis of a High-Resolution Model Climatology
Authors: van Lipzig Nicole P. M. , Marshall Gareth J. , Orr Andrew , King John C.
Published: April 2008

The large regional summer warming on the east coast of the northern Antarctic Peninsula (AP), which has taken place since the mid-1960s, has previously been proposed to be caused by a trend in the Southern Hemisphere Annular Mode (SAM). The authors utilize a high-resolution regional atmospheric model climatology (14-km grid spacing) to study the mechanisms that determine the response of the near-surface temperature to an increase in the SAM (ΔT/ΔSAM). Month-to-month variations in near-surface temperature and surface pressure are well represented by the model. It is found that north of ∼68°S, ΔT/ΔSAM is much larger on the eastern (lee) side than on the western (windward) side of the barrier. This is because of the enhanced westerly flow of relatively warm air over the barrier, which warms (and dries) further as it descends down the lee slope. The downward motion on the eastern side of the barrier causes a decrease in surface-mass balance and cloud cover. South of ∼68°S, vertical deflection across the barrier is greatly reduced and the contrast in ΔT/ΔSAM between the east and west sides of the barrier vanishes. In the northeastern part of the AP, the modeled ΔT/ΔSAM distribution is similar to the distribution derived from satellite infrared radiometer data. The region of strongest modeled temperature sensitivity to the SAM is where ice shelf collapse has recently taken place and does not extend farther south over the Larsen-C Ice Shelf.
A Hidden Markov Model Perspective on Regimes and Metastability in Atmospheric Flows
Authors: Franzke Christian , Crommelin Daan , Fischer Alexander , Majda Andrew J.
Published: April 2008

In this study, data from three atmospheric models are analyzed to investigate the existence of atmospheric flow regimes despite nearly Gaussian statistics of the planetary waves in these models. A hierarchy of models is used, which describes the atmospheric circulation with increasing complexity. To systematically identify atmospheric regimes, the presence of metastable states in the data is searched for by fitting so-called hidden Markov models (HMMs) to the time series.

A hidden Markov model is designed to describe the situation in which part of the information of the system is unknown or hidden and another part is observed. Within the context of this study, some representative variable of planetary-scale flow (e.g., mean zonal flow or leading principal component) is known (“observed”), but its dynamics may depend crucially on the overall flow configuration, which is unknown. The behavior of this latter, “hidden” variable is described by a Markov chain. If the Markov chain possesses metastable (or quasi persistent) states, they are identified as regimes. In this perspective, regimes can be present even though the observed data have a nearly Gaussian probability distribution. The parameters of the HMMs are fit to the time series using a maximum-likelihood approach; well-established and robust numerical methods are available to do this. Possible metastability of the Markov chain is assessed by inspecting the eigenspectrum of the associated transition probability matrix. The HMM procedure is first applied to data from a simplified model of barotropic flow over topography with a large-scale mean flow. This model exhibits regime behavior of its large-scale mean flow for sufficiently high topography. In the case of high topography, the authors find three regimes, two of which correspond to zonal flow and the third to blocking.

Next, a three-layer quasigeostrophic model is used as a prototype atmospheric general circulation model (GCM). Its first empirical orthogonal function (EOF) is similar to the Arctic Oscillation (AO) and exhibits metastability. For this model, two regime states are found: one corresponding to the positive phase of the AO with large amplitude and decreased variability of the streamfunction field, and another corresponding to the negative AO phase with small amplitude and increased variability. Finally, the authors investigate a comprehensive GCM. The leading four EOFs of this model show no signs of metastability. The results of the barotropic flow over topography and of the quasigeostrophic model suggest that the observed small skewness of planetary wave probability density functions (PDFs) is an imprint of blocked circulation states.
Mechanism of the Asymmetric Monsoon Transition as Simulated in an AGCM
Authors: Wang Zhuo , Chang C-P.
Published: April 2008

Atmospheric general circulation model (AGCM) simulations are carried out to test a hypothesis (Chang et al.) for the asymmetric monsoon transition in which the maximum convection marches gradually from the Asian summer monsoon to the Asian winter monsoon during boreal fall but experiences a sudden transition in the reverse during boreal spring. In the control run, the AGCM is driven by the climatological mean sea surface temperature (SST) with a realistic annual cycle, and it reproduces the observed asymmetric monsoon transition. In the sensitivity test, the model is driven by a similarly realistic SST but whose annual cycle is symmetric. The northwestward march of the maximum convection in boreal spring becomes more gradual, resulting in an overall near-symmetric pattern for the monsoon seasonal transition. The AGCM simulations confirm the hypothesis that the atmospheric mass redistribution due to the different land–ocean thermal memories leads to a seasonally different horizontal convergence field and it facilitates the southeastward monsoon march in boreal fall, while it hinders the northwestward monsoon march in boreal spring, contributing to the asymmetric monsoon transition.
A Comparison Study of Three Polar Grids
Authors: Chen Tsing-Chang , Tsay Jenq-Dar , Gutowski William J.
Published: April 2008

The circumference of a latitude circle decreases toward the Poles, making it difficult to present meteorological field variables on equally spaced grids with respect to latitude and longitude because of data aggregation. To identify the best method for displaying data at the Poles, three different grids are compared that have all been designed to reduce data aggregation: the reduced latitude–longitude (RL) grid, the National Snow and Ice Data Center Equal-Area Special Sensor Microwave Imager (SSM/I) Earth (EA) grid, and the National Meteorological Center octagonal (OG) grid. The merits and disadvantages of these grids are compared in terms of depictions of the Arctic summer circulation with wind vectors, streamfunction, and velocity potential at 400 hPa where maximum westerlies are located. Using geostrophy, the 400-hPa streamfunction at high latitudes can be formed from geopotential height. In comparison with this geostrophic streamfunction, the streamfunction generated from vorticity on the OG grid shows a negligible error (∼0.5%). The error becomes larger using vorticity on the EA (∼15%) and RL (∼30%) grids. During the northern summer, the Arctic circulation at 400 hPa is characterized by three troughs. The streamfunction and velocity potential of these three troughs are spatially in quadrature with divergent (convergent) centers located ahead of (behind) these troughs. These circulation features are best depicted by the streamfunction and velocity potential generated on the OG grid. It is demonstrated by these findings that the National Meteorological Center octagonal grid is the most ideal among the three grids used for the polar regions. However, this assessment is constrained by the hemispheric perspective of meteorological field variables, because these variables depicted on the octagonal grid at higher latitudes need to be merged with those on the equal-latitude-longitude grid at lower latitudes.
Effects of Trade-Wind Strength and Direction on the Leeside Circulations and Rainfall of the Island of Hawaii
Authors: Yang Yang , Chen Yi-Leng , Fujioka Francis M.
Published: April 2008

The leeside circulations and weather of the island of Hawaii were studied from the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) land surface model simulations for eight strong (∼7.9 m s−1) and eight weak (∼5.2 m s−1) trade-wind days and for five days with southeasterly trades (∼7.1 m s−1) during summer 2004. The objective is to investigate the effects of trade-wind strength and directions on the leeside circulations and rainfall and the modification of these effects by the land surface thermal forcing. For the small wake on the lee side of the Kohala Mountains (1700 m, lower than the trade-wind inversion at 2000 m) over northern Hawaii, the hydraulic jump is present with stronger downslope winds and warmer and drier conditions on the lee side and a weaker westerly reversed flow offshore when trades are stronger. In contrast, the westerly reversed flow along the large wake axis off the central Kona leeside coast (behind massive mountains with tops >4000 m) is 1–1.5 m s−1 stronger and 200–300 m deeper with higher moisture content when trades are stronger. Over the Kona slopes, the daytime thermally direct circulation cell is more significant when trades are stronger because of descending airflow aloft with less cloudiness. In the evening, the convergence between the westerly reversed flow offshore along the wake axis and the offshore/katabatic flow in the Kona coastal region is more significant with higher evening rainfall when trades are stronger. During the day, the lee side of the Kohala Mountains is characterized by a reversed flow (∼4 m s−1) merging with sea-breeze circulations along the coast. When trades are stronger, the convergence between the anabatic winds and the descending flow from the upper slopes is greater. However, the simulated cloud water there is less under strong trades because of warmer and drier conditions due to significant adiabatic descent in the lee. At night, when trades are stronger, the combined downslope/katabatic flow prevails without a reversed flow offshore. Under a southeasterly trade-wind flow with a lower trade-wind inversion (1.5 km), the westerly reversed flow is shallower; the adiabatic descent aloft on the southwestern leeside areas is more significant with warmer temperatures (0.5 K), a larger negative potential vorticity maximum [0.2 potential vorticity units (PVU), 1 PVU = 10−6 K m2 s−1 kg−1], and a more pronounced anticyclonic vortex offshore. The westerly reversed flow off the Kona coast shifts northward.
School and Parental Influences on Sociopolitical Development Among Poor Adolescents of Color
Authors: Diemer Matthew A. , Hsieh Chueh-an , Pan Tianshu
Published: April 2008

Sociopolitical development represents a motivation to reduce sociopolitical inequity, a healthy sense of the self, and perceived agency in the context of structural oppression. Sociopolitical development has been associated with progress in career development, school engagement, and healthier sexual behavior among oppressed and marginalized adolescents. However, knowledge of outcomes that sociopolitical development may facilitate has outpaced knowledge of what may facilitate sociopolitical development. This paper examines key aspects of adolescents' context—the school and parents—and their potential influence on the sociopolitical development of poor adolescents of color. This research question is examined with 2,078 National Educational Longitudinal Survey participants. The obtained structural equation model suggests that parental support and student racial relations are predictive of sociopolitical development. These results provide empirical support for extant sociopolitical development models and illuminate our understanding of a critical social justice issue. These results inform sociopolitical development interventions, counseling practice, and scholarly understanding of how oppressed adolescents cope with sociopolitical inequity.
Rapid Serial Naming Is a Unique Predictor of Spelling in Children
Authors: Savage Robert , Pillay Vanitha , Melidona Santo
Published: April 2008

Some previous research has shown strong associations between spelling ability and rapid automatic naming (RAN) after controls for phonological processing and nonsense-word reading ability, consistent with the double-deficit hypothesis in reading and spelling. Previous studies did not, however, control for nonsense-word spelling ability before assessing RAN—spelling associations. In this study, 65 children with poor spelling skills but average reasoning ability completed RAN tasks and spelling, reading, and reasoning tasks. Hierarchical regression analyses revealed that, after controls for chronological age, reasoning ability, and spelling of nonsense words, alphanumeric RAN, but not nonalphanumeric RAN, was still a strong predictor of spelling acquisition. Findings are discussed in terms of single- and double-deficit models of spelling and implications for effective teaching.
Mothers' Causal Attributions Concerning the Reading Achievement of Their Children With and Without Familial Risk for Dyslexia
Authors: Natale Katja , Aunola Kaisa , Nurmi Jari-Erik , Poikkeus Anna-Maija , Lyytinen Paula , Lyytinen Heikki
Published: April 2008

The present study analyzed data from the Jyväskylä Longitudinal Study of Dyslexia to investigate the factors to which mothers of children with and without familial risk for dyslexia attribute the causes of their first-grade children's reading achievement. Mothers' causal attributions were assessed three times during their children's first school year. Children's verbal intelligence was assessed at 5 years and their word and nonword reading skills at 6.5 years. The results showed that the higher the word reading skills the children had, the more their mothers attributed their success to ability than to effort. However, if children had familial risk for dyslexia, their mothers' attribution of success to ability decreased during the first grade as compared with the ability attributions of mothers whose children were in the control group.
Is There an Increased Familial Prevalence of Psychopathology in Children With Nonverbal Learning Disorders?
Authors: Antshel Kevin M. , Khan Fahad M.
Published: April 2008

The cognitive and behavioral symptoms of nonverbal learning disabilities (NLD) have been described by previous investigators. Nevertheless, we know far less about the potential genetic contributions that may predispose a child to have NLD. An endophenotype model was investigated in 5 samples of children ages 9 to 15 years: NLD ( n = 32); reading disorders (RD; n = 59); participants with a psychiatric diagnosis but without a learning disability ( n = 55); typically developing controls ( n = 31); and children with velocardiofacial syndrome (VCFS), a chromosomal deletion syndrome that has been proposed as being an exemplar of NLD (VCFS + NLD; n = 20). Based on a family genetic interview, the authors' data suggest that children with NLD, RD, or a psychiatric diagnosis have a higher prevalence rate of attention-deficit/hyperactivity disorder (ADHD) and substance abuse/dependence. Psychiatric controls and children with NLD—but not children with RD— showed higher prevalence rates of familial bipolar disorder.
Academic Underachievement Among Children With Epilepsy
Authors: Fastenau Philip S. , Jianzhao Shen  , Dunn David W. , Austin Joan K.
Published: April 2008

This study assessed rates of learning disabilities (LD) by several psychometric definitions in children with epilepsy and identified risk factors. Participants ( N = 173, ages 8—15 years) completed IQ screening, academic achievement testing, and structured interviews. Children with significant head injury, chronic physical conditions, or mental retardation were excluded. Using an IQ—achievement discrepancy definition, 48% exceeded the cutoff for LD in at least one academic area; using low-achievement definitions, 41% to 62% exceeded cutoffs in at least one academic area. Younger children with generalized nonabsence seizures were at increased risk for math LD using the IQ—achievement discrepancy definition; age of seizure onset and attention-deficit/hyperactivity disorder (ADHD) were risk factors for reading and math LD using low-achievement definitions. Writing was the most common domain affected, but neither ADHD nor seizure variables reliably identified children at risk for writing LD. Although children with earlier seizure onset, generalized nonabsence seizures, and comorbid ADHD appear to be at increased risk for some types of LD by some definitions, these findings largely suggest that all children with epilepsy should be considered vulnerable to LD. A diagnosis of epilepsy (even with controlled seizures and less severe seizure types) should provide sufficient cause to screen school-age children for LD and comorbid ADHD.
Effects of Multilayer Clothing System Array on Water Vapor Transfer and Condensation in Cold Weather Clothing Ensemble
Authors: Yoo Shinjung , Kim Eunae
Published: April 2008

In order to improve designs and material development, it is necessary to evaluate the performance of multilayer cold weather clothing ensembles under real usage conditions. At low temperatures, condensation always occurs when a wearer sweats, and this influences the heat and moisture transfer characteristics of a clothing system. The layer array effects of multilayer cold weather clothing ensembles on heat and moisture transfer and condensation profiles were examined by using the Human-Clothing-Environment simulator. Three different fabric arrangements consisted of identical five-layer fabrics were exposed to 2 and 5 mL of sweat pulses under a —15°C climatic condition. The temperature and vapor concentration profiles within each microclimate were assessed over time and the amount of condensation on each layer was measured after an hour of exposure. Most of the condensation took place on the outer surface of the second and third fleece fabrics, not on the inside of the waterproof breathable outer shell. Without altering materials, the layer arrangement itself influenced the condensation profiles, as well as the heat and water vapor permeability of the clothing ensembles. Combining an insulating layer with an outer shell caused clothing systems to exhibit better water vapor permeability and less moisture accumulation. The distribution of condensed water on each layer was also influenced by the layer arrangement.
A Geometrical Model for the Double Lacoste Knits
Authors: Kurbak Arif , Alpyildiz Tuba
Published: April 2008

Geometrical modeling of the double lacoste knitted fabrics is studied. Elliptical shapes for the head of loops (tuck and plain), general helices and lemniscate curve for the rest of the parts including the arms of the loops are used. The coordinates of the points on the fitting curves are found and these points are used in the simulation of the front and back views of the double lacoste knitted fabrics. A proper geometric definition of the double lacoste structure is given to be used in further analysis, such as finite element method applications. With this model it will be possible to obtain the 3D appearance of the fabric using basic experimental results as inputs.
Basic Studies for Modeling Complex Weft Knitted Fabric Structures Part II: A Geometrical Model for Plain Knitted Fabric Spirality
Authors: Kurbak Arif , Kayacan Ozlem
Published: April 2008

A model for the spirality of plain knitted fabrics with compressible yarns is given here by modifying Kurbak's (1998) plain knitted loop model. The proposed model is thought to be applicable not only to the spirality of classical textiles, but also to modeling small diameter tubular technical textile fabrics. In the present study, it is suggested that because of the three-dimensional nature of the plain loop, the yarn part at the left arm of the loop and the yarn part at the right arm of the loop have torsions in opposite directions, so that if the yarn used is already twist lively, this potential twist applies in the same direction for both of the arms. Therefore, the total twist decreases in one arm and increases in the other. To equalize their total twists, the curves of the yarn axis in the arms differ from each other (the elliptical cylinders on which the yarn arms wrapped differ in length and in radius). The upper and lower parts of the loop adjust themselves by transforming into parametric elliptical shapes from their original elliptical shapes. There is another method of twist redistribution in the fabrics, which is to differentiate the wrapping angles of the helices on two arms of a loop. This is defined as “the second kind of spirality” and is mainly seen in m × n rib structures as well as in some of the technical textile plain knitted fabrics. This second kind of spirality is not considered during the creation of the model, but a discussion is given on this subject at the end of the work.
Basic Studies for Modeling Complex Weft Knitted Fabric Structures Part I: A Geometrical Model for Widthwise Curlings of Plain Knitted Fabrics
Authors: Kurbak Arif , Ekmen Ozgur
Published: April 2008

A geometrical model for widthwise curlings in plain knitted structures is suggested here based on the plain knitted fabric model of Kurbak (1998). The main aim is to create models of m × n rib fabrics and also to model small diameter tubular fabrics. The model obtained is drawn to scale using the 3DS-MAX computer graphics program. With this model, the changes in radius of curvature at each part of the loop are shown.
Comparison of the Effects of Cotton Yarns Produced by New, Modified and Conventional Spinning Systems on Yarn and Knitted Fabric Performance
Authors: Beceren Yeşim , Nergis Banu Uygun
Published: April 2008

This research, which is divided into two parts, is a comparative study of the physical properties of cotton yarns produced by using new, modified and conventional spinning methods. The first part focuses on the performance of yarns with a final count of Ne 20 produced by conventional and compact spinning methods, whereas the second part focuses on the performance of Ne 30 combed ring, compact and vortex cotton yarns. Effects of the tested properties of the yarns on the performance of fabrics knitted have also been studied. Results showed that the structural differences of each yarn type conferred different tensile, evenness and hairiness values, and the differences in the yarn structure were reflected onto the fabric properties.
Dyeing Properties of Modified Gemini Surfactants on a Disperse Dye—polyester System
Authors: Lai Chiu-Chun , Chen Keng-Ming
Published: April 2008

We have studied the dispersing abilities of a series of modified Gemini surfactants toward commercial disperse dyes at elevated temperature, and the corresponding effects during polyester dyeing. From measurements of the dispersibilities and particle sizes of the dye solutions, we found that the surfactants exhibited good dispersing ability. Spectrophotometric methods confirmed that dye—surfactant complexes had formed. During the dyeing of polyester fabrics, the dyeing rate decreased when the surfactants were present because the hydrophilic dye—surfactant complexes enhanced the solubility of the disperse dyes.
Novel Technique to Align Fabric in Image Analysis
Authors: Jeong Youngjin
Published: April 2008

The image analysis technique for finding the directions of warp and weft is introduced. The method is applied to some adorned fabrics like stripe, check, and dogtooth as well as unadorned fabrics of basic weaves to verify its efficiency and accuracy. Also, the parameters affecting the results are discussed. The method predicts well the warp and weft directions for adorned fabric as well as unadorned fabrics of basic weaves. Thus, the method can be useful in the image analysis area for textiles, especially, for determining fabric density.
Slub Extraction in Woven Fabric Images Using Gabor Filters
Authors: Xiuping Liu  , Zhijie Wen  , Zhixun Su  , Choi Ka-Fai
Published: April 2008

This paper reports the investigation of two different approaches for the extraction of images of slub yarns from woven fabrics (slub extraction) using Gabor filters. We present two methods of designing Gabor filters for extracting slub in both the time domain and the frequency domain. The first method selects a better filter in the time domain according to a designed cost function. The second method obtains the proper parameters for the filter in the frequency domain according to the frequency characteristic of slubs. The experimental results with real woven fabric images confirm the usefulness of the two approaches proposed in this paper. The latter is found to be better than the former. Further, both methods are superior to the existing algorithm.