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Flattening
Selected AbstractsFlattGen: Teaching tool for surface flatteningCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2006Simon Kolmani Abstract In many cases in the industry, we can face a problem, where an object has to be manufactured out of thin plane material. This is especially the case in the car, airplane, shipbuilding, textile, and shoe making industry. In order to manufacture such an object, a pattern has to be generated first. It has to be cut out from plane material and then bend to the final shape. The same problem can be found also in computer graphics, where flat patterns are used to decrease distortions in texture mapping. Therefore, it is important for designers and computer engineers to master the flat pattern generation. In literature, a great number of methods for pattern generation can be found and it is important to know their advantages and weaknesses. In this article, the application FlattGen is presented where the most important flattening methods can be seen and compared to each other. In this way, students can experiment and prepare themselves better for the future work. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 106,119, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20060 [source] Simulation Study of the MHD Stability Beta Limit in LHD by TASK3DCONTRIBUTIONS TO PLASMA PHYSICS, Issue 6-7 2010M. Sato Abstract The numerical method for analysis of the "MHD stability beta limit" based on a hierarchy integrated simulation code TASK3D has been developed. The numerical model for the effect of the MHD instabilities is introduced such that the pressure profile is flattened around the rational surface due to the MHD instabilities. The width of the flattening of the pressure gradient is determined from the width of the eigenmode structure of the MHD instabilities (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Compaction of cell shape occurs before decrease of elasticity in CHO-K1 cells treated with actin cytoskeleton disrupting drug cytochalasin DCYTOSKELETON, Issue 4 2009Christian Schulze Abstract The actin filaments of the cytoskeleton form a highly dynamic polymer scaffold which is actively involved in many essential mechanisms such as cell migration, transport, mitosis, and mechanosensitivity. We treated CHO-K1 cells with different concentrations of the actin cytoskeleton disrupting drug cytochalasin D. Then investigating the cells' elastic behaviour by scanning force microscopy-based rheology we confirmed for high cytochalasin D concentrations (,1.5 ,M) a significant decrease of mechanical stability. At lower concentrations we measured no significant softening, but flattening and a horizontal contraction was observable even at low concentrations (,0.3 ,M) of cytochalasin D. The observed changes in cell shape resulted in a lower cell volume, showing that there is compensation by volume for small decreases in cytoskeletal strength resulting from reduced numbers or lengths of actin filaments. These results suggest that the characteristic functions defining a cell's mechanical stability such as mechanosensitivity can be maintained via small changes in cell volume in order to counter fluctuations in cytoskeletal composition. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Full Scope of Effect of Facial Lipoatrophy: A Framework of Disease UnderstandingDERMATOLOGIC SURGERY, Issue 8 2006BENJAMIN ASCHER MD BACKGROUND Facial lipoatrophy has been observed to occur in a variety of patient populations, with inherited or acquired disease, or even in aging patients as a natural progression of tissue change over time. There is currently no framework from which physicians of all medical specialties can communally discuss the manifestations, diagnoses, and management of facial lipoatrophy. OBJECTIVE The aim of this assembly was to derive a definition of facial lipoatrophy capable of being applied to all patient populations and develop an accompanying grading system. RESULTS The final consensus of the Facial Lipoatrophy Panel encompasses both aging and disease states: "Loss of facial fat due to aging, trauma or disease, manifested by flattening or indentation of normally convex contours." The proposed grading scale includes five gradations (Grades 1,5; 5 being the most severe), and the face is assessed according to three criteria: contour, bony prominence, and visibility of musculature. CONCLUSION Categorizing the presentation of facial lipoatrophy is subjective and qualitative, and will need to be validated with objective measures. Furthermore, during the assembly, several topics were exposed that warrant further research, including the physiology of volume loss, age and lipoatrophy, and human immunodeficiency virus and lipoatrophy. [source] The subjective experience of taking antipsychotic medication: a content analysis of Internet dataACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2009J. Moncrieff Objective:, We explored the subjective effects associated with olanzapine, risperidone and older antipsychotics. Method:, We conducted a content analysis of an Internet database of comments about prescribed medications. Results:, We analysed 223 comments on risperidone, 170 on olanzapine and 46 relating to three older antipsychotics. The predominant subjective effects produced by all drugs consisted of sedation, cognitive impairment and emotional flattening or indifference. Connections appeared between these effects and Parkinsonian-like symptoms with the older drugs, sexual impairment with risperidone and metabolic effects with olanzapine. The experience of akathisia was frequently linked to suicidal thoughts. Some respondents described how the drugs' subjective effects helped to reduce symptoms of mania, psychosis and anxiety. Conclusion:, The generalisability of Internet data is uncertain. However, the data suggest that adverse subjective effects play a central role in the experience of taking antipsychotic drugs and may be related to the drugs' desired benefits. [source] Effect of Injection Parameters on Velocity and Temperature Distributions of Alumina-Titania In-Flight Particles in Atmospheric Plasma SprayingADVANCED ENGINEERING MATERIALS, Issue 8 2004S. Guessasma Three injection parameters (carrier gas flow rate, injector diameter and injection distance) were correlated to the characteristic distributions in the case of alumina titania in-flight particles. A high speed two color pyrometer was implemented to measure, at the centre of the particle flow, individual in-flight particle characteristics, which were used to build velocity and temperature distributions. Results showed that mean characteristic variations were explained by distribution width flattening and centre shift. These were not significant compared to energetic parameter effects. [source] New P-ligands: The aromaticity and reactivity of 2,4,6-trialkylphenylphospholesHETEROATOM CHEMISTRY, Issue 2 2005György Keglevich A further member of 2,4,6-trialkyl-phenyl-phos-pholes, the ditertbutylmethylphenyl derivative (1c) was characterized by Bird index and by the sum of angles at the phosphorus atom to describe the flattening of the P-pyramid. Both numbers suggested a slight aromaticity. The reaction of arylphospholes with phosphorus tribromide was extended to phosphole 1c leading this occasion, after further steps, to the mixture of 3- and 2-substituted products (3c-1 and 3c-2, respectively). A triisopropylphenyl-2H -phosphole (4) formed by sigmatropic rearrangement was utilized in the preparation of new 1-phosphanorbornene derivatives, such as sulfide 6 and hemi-oxides 8-1 and 8-2. Further oxidation of the latter species (8-1 and 8-2) led to the decomposition of the dimeric structure (11). 4 could also be trapped by benzaldehyde to afford the oxaphosphanorbornene (10) as one diastereomer. Finally, the reversible formation of 2H -phosphole 4 from 1H -phosphole 1a at 150°C was proved. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:104,222, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20077 [source] Quetiapine versus olanzapine for the treatment of negative symptoms in patients with schizophreniaHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 4 2006Pinkhas Sirota Abstract Negative symptoms are considered the most debilitating and refractory aspect of schizophrenia, being associated with poor social, occupational and global outcomes. Conventional antipsychotics have limited efficacy against these symptoms and poor tolerability profiles. Atypical antipsychotics are an alternative treatment, and this 12-week, randomised, flexibly dosed study compared the efficacy, safety and tolerability of quetiapine and olanzapine in this regard. Of the 40 patients who entered the study (32 male; 8 female), 19 were randomised to quetiapine (mean dose 637,mg/day, mean treatment duration 80 days) and 21 to olanzapine (mean dose 16,mg/day, mean treatment duration 78 days). Quetiapine and olanzapine were similarly effective: in each treatment group significant improvements at Week 12 were observed for negative symptom scores on the SANS and the PANSS, and for subscale scores of affective flattening and alogia on the SANS. Both treatments were well tolerated in this patient population, with no worsening of extrapyramidal symptoms in either case. Anxiety and insomnia were the most common adverse events (,7% of patients in each group), but were not drug-related. Although this is a small study with limited power, the results support the effectiveness of quetiapine and olanzapine in treating the negative symptoms of schizophrenia. Copyright © 2006 John Wiley & Sons, Ltd. [source] A Japanese case of Kindler syndromeINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2000Yasushi Suga MD A 25-year-old Japanese woman presented with contracture of the fingers and toes, and difficulty in opening her mouth. Her grandparents are first cousins, but none of the other members of the family are affected. Bulla formation started at birth on areas of the skin that received pressure, and in infancy and early childhood the lesions were limited only to the acral areas. She also had bilateral, incomplete syndactylies involving all web spaces ( Fig. 1a). The formation of blisters ceased after the age of 15 years, but a generalized progressive poikiloderma then appeared with accompanying cutaneous atrophy of the skin of the neck, trunk, and extremities ( Fig. 1b). The patient experienced mild photosensitivity of the face and neck. At age 18 years, surgical removal of the webbing of all her fingers was performed. Oral examination showed atrophy of the buccal mucosa, and an inability to fully open the mouth. The patient also suffered from poor dentition and easily bleeding gums, but had no symptoms of esophageal dysfunction. Figure 1. Clinical manifestations of the patient with Kindler syndrome. (a) Dorsal surface of the patient's hands. Note the marked cutaneous atrophy with a severely wrinkled appearance on the dorsal surface of the hands, as well as the proximal fusion of the fingers. (b) Lower left leg of the patient. Atrophic thinning of the skin and poikiloderma with reticular pigmentation are evident Histology of separate biopsy specimens, taken from the poikilodermatous pretibial and trunk skin, showed classical features of poikiloderma, namely epidermal atrophy with flattening of the rete ridges, vacuolization of basal keratinocytes, pigmentary incontinence, and mild dermal perivascularization ( Fig. 2a). Interestingly, dyskeratotic cells ( Fig. 2b) and eosinophilic rounded bodies (colloid bodies) ( Fig. 2c) were frequently found at the basal keratinocyte layer and in the upper dermis, respectively. Pigment was also present in the upper epidermis. Figure 2. Hematoxylin and eosin staining of a biopsy specimen taken from pretibial skin. (a) Epidermal atrophy with flattening of the rete ridges. Note the dyskeratotic cells (arrowheads) and vacuolar degeneration of the basal layer in the epidermis. Bar = 50 ,m. (b) Higher magnification of dyskeratotic cells (arrowheads). Bar = 10 ,m. (c) Higher magnification of colloid bodies (arrowheads) in the superficial dermis. Bar = 10 ,m To rule out the possibility of a congenital epidermolysis bullosa, ultrastructural and immunofluorescence studies were performed. Ultrastructural studies demonstrated the reduplication of the basal lamina with branching structures within the upper dermis and cleavage between the lamina densa and the cell membrane of the keratinocytes ( Fig. 3a). The numbers of associated anchoring fibrils did not seem to be reduced, and colloid bodies and dyskeratotic cells were detected. Immunofluorescence studies with the antibody against type VII collagen (LH 7 : 2) were subsequently carried out. The results showed extensive broad bands with intermittently discontinuous and reticular staining at the dermo-epidermal junction (DEJ) ( Fig. 3b), whereas a linear distribution is typically seen in healthy tissue (data not shown). Interestingly, direct immunofluorescence studies revealed intracellular accumulation of immunoglobulin G (IgG), IgM, IgA, and C3 in colloid bodies under the basement membrane ( Fig. 3c). Figure 3. Ultrastructural and immunohistochemical findings of the patient with Kindler syndrome. (a) Ultrastructural study of the dermo-epidermal junction. The branching structures of the lamina densa (arrowheads) were frequently seen. The asterisks show the cleavage in the lamina lucida. Bar = 1 ,m. (b) Immunohistochemical studies with the antibody to type VII collagen (LH 7 : 2). An extensive broad band with reticular patterns is evident. Bar = 50 ,m. E, epidermis; D, dermis. (c) Direct immunofluorescence study. Intracytoplasmic deposition of IgM in the basal keratinocytes is evident (arrowheads). Bar = 50 ,m. E, epidermis; D, dermis [source] A high status burial from Ripon Cathedral, North Yorkshire, England: differential diagnosis of a chest deformityINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2003S. Groves Abstract Excavations beneath the crossing at Ripon Cathedral in North Yorkshire recently revealed a burial radiocarbon dated to the late 15th century AD. The burial was that of a young adult female; the location of the grave suggests a person of relatively high status. The very well preserved skeleton revealed abnormal changes to the bones of the thoracic cavity including anterior bowing of the sternum, flattening of the spinous processes of thoracic vertebrae three to nine against the processes below each one, and changes to the ribs that suggested anterior displacement of the rib cage. The skeletal changes are described and differential diagnoses presented. Treatment to an underlying chest deformity, ,pectus carinatum', is thought to be the underlying cause of the skeletal changes; this study may lend direct insight into the concepts of body image in the Medieval period. Copyright © 2003 John Wiley & Sons, Ltd. [source] Can Renal Acute Tubular Necrosis Be Differentiated from Autolysis at Autopsy?,JOURNAL OF FORENSIC SCIENCES, Issue 2 2009Linda Kocovski B.Sc. Abstract:, We investigate the morphological characteristics that may differentiate between ischemic acute tubular necrosis (ATN) and autolysis in postmortem samples. Renal tissue from 57 postmortem cases with an antemortem diagnosis of ATN and 57 age-/sex-matched control cases were examined for 10 morphological characteristics: epithelial proliferation (Ki-67 immunoperoxidase positivity), fibrin thrombi, tubular epithelial whorls, mitoses, casts, autolysis, tubulorrhexis, epithelial flattening, interstitial inflammation, and interstitial expansion. Tubular epithelial whorls were found in 16 ATN cases and were absent in controls. These findings suggest that specific morphological criteria may distinguish ischemic ATN from autolysis. Diagnoses of ATN may be confirmed using these combined criteria as contributing to cause of death and/or to ascertain previously undiagnosed cases of ATN postmortem. [source] Vertical extrusion and middle crustal spreading of omphacite granulite: a model of syn-convergent exhumation (Bohemian Massif, Czech Republic)JOURNAL OF METAMORPHIC GEOLOGY, Issue 3 2004típská Abstract The exhumation of eclogite facies granulites (Omp,Plg,Grt,Qtz,Rt) in the Rychleby Mts, eastern Czech Republic, was a localised process initiated by buckling of crustal layers in a thickened orogenic root. Folding and post-buckle flattening was followed by the main stage of exhumation that is characterized by vertical ductile extrusion. This process is documented by structural data, and the vertical ascent of rocks from a depth of c. 70 to c. 35 km is documented by metamorphic petrology. SHRIMP 206Pb/238U and 207Pb/206Pb evaporation zircon ages of 342 ± 5 and 341.4 ± 0.7 Ma date peak metamorphic conditions. The next stage of exhumation was associated with sideways flat thrusting associated with lateral viscous spreading of granulites and surrounding rocks over indenting adjacent continental crust at a depth of c. 35,30 km. This stage was associated with syntectonic intrusion of a granodiorite sill at 345,339 Ma, emplaced at a crustal depth of c. 25 km. The time required for cooling of the sill as well as for heating of the country rocks brackets this event to a maximum of 250 000 years. Therefore, similar ages of crystallization for the granodiorite magma and the peak of eclogite facies metamorphism of the granulite suggest a very short period of exhumation, limited by the analytical errors of the dating methods. Our calculations suggest that the initial exhumation rate during vertical extrusion was 3,15 mm yr,1, followed by an exhumation rate of 24,40 mm yr,1 during further uplift along a magma-lubricated shear zone. The extrusion stage of exhumation was associated with a high cooling rate, which decreased during the stage of lateral spreading. [source] Chemical and physical responses to deformation in micaceous quartzites from the Tauern Window, Eastern AlpsJOURNAL OF METAMORPHIC GEOLOGY, Issue 4 2003J. Selverstone Abstract Micaceous quartzites from a subvertical shear zone in the Tauern Window contain abundant quartz clasts derived from dismembered quartz-tourmaline veins. Bulk plane strain deformation affected these rocks at amphibolite facies conditions. Shape changes suggest net shortening of the clasts by 11,64%, with a mean value of 35%. Quartz within the clasts accommodated this strain largely via dislocation creep processes. On the high-stress flanks of the clasts, however, quartz was removed via solution mass transfer (pressure solution) processes; the resulting change in bulk composition allowed growth of porphyroblastic staurolite + chlorite ± kyanite on the clast flanks. Matrix SiO2 contents decrease from c. 83 wt% away from the clasts to 49,58% in the selvages on the clast flanks. The chemical changes are consistent with c. 70% volume loss in the high-stress zones. Calculated shortening values within the clast flanks are similar to the volume-loss estimates, and are greatly in excess of the shortening values calculated from the clasts themselves. Flow laws for dislocation creep versus pressure solution imply large strain-rate gradients and/or differential stress gradients between the matrix and the clast selvages. In a rock containing a large proportion of semirigid clasts, weakening within the clast flanks could dominate rock rheology. In our samples, however, weakening within the selvages was self limiting: (1) growth of strong staurolite porphyroblasts in the selvages protected remaining quartz from dissolution; and (2) overall flattening of the quartz clasts probably decreased the resolved shear stress on the flanks to values near those of the matrix, which would have reduced the driving force for solution-transfer creep. Extreme chemical changes nonetheless occurred over short distances. The necessity of maintaining strain compatibility may lead to significant localized dissolution in rocks containing rheologic heterogeneities, and overall weakening of the rocks may result. Solution-transfer creep may be a major process whereby weakening and strain localization occur during deep-crustal metamorphism of polymineralic rocks. [source] What Makes the Output,Inflation Trade-Off Change?JOURNAL OF MONEY, CREDIT AND BANKING, Issue 6 2009The Absence of Accelerating Deflation in Japan Phillips curve; time-varying parameter models; endogenous pricing It is standard to model the output,inflation trade-off as a linear relationship with a time-invariant slope. We assess empirical evidence for two sets of theories that allow for endogenous variation in the slope of the short-run Phillips curve. At an empirical level, we examine why large negative output gaps in Japan in the late 1990s did not lead to accelerating deflation but instead coincided with stable, albeit moderately negative inflation. Our results suggest that this episode is most convincingly interpreted as reflecting a gradual flattening of the Phillips curve. We find that this flattening is best explained by models with endogenous price durations. These models imply that in any economy where trend inflation is substantially lower (or substantially higher) today than in past decades, time variation in the slope of the Phillips curve has become too important to ignore. [source] Regulation of implant surface cell adhesion: characterization and quantification of S-phase primary osteoblast adhesions on biomimetic nanoscale substratesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2007Manus J.P. Biggs Abstract Integration of an orthopedic prosthesis for bone repair must be associated with osseointegration and implant fixation, an ideal that can be approached via topographical modification of the implant/bone interface. It is thought that osteoblasts use cellular extensions to gather spatial information of the topographical surroundings prior to adhesion formation and cellular flattening. Focal adhesions (FAs) are dynamic structures associated with the actin cytoskeleton that form adhesion plaques of clustered integrin receptors that function in coupling the cell cytoskeleton to the extracellular matrix (ECM). FAs contain structural and signalling molecules crucial to cell adhesion and survival. To investigate the effects of ordered nanotopographies on osteoblast adhesion formation, primary human osteoblasts (HOBs) were cultured on experimental substrates possessing a defined array of nanoscale pits. Nickel shims of controlled nanopit dimension and configuration were fabricated by electron beam lithography and transferred to polycarbonate (PC) discs via injection molding. Nanopits measuring 120 nm diameter and 100 nm in depth with 300 nm center,center spacing were fabricated in three unique geometric conformations: square, hexagonal, and near-square (300 nm spaced pits in square pattern, but with ±50 nm disorder). Immunofluorescent labeling of vinculin allowed HOB adhesion complexes to be visualized and quantified by image software. Perhipheral adhesions as well as those within the perinuclear region were observed, and adhesion length and number were seen to vary on nanopit substrates relative to smooth PC. S-phase cells on experimental substrates were identified with bromodeoxyuridine (BrdU) immunofluorescent detection, allowing adhesion quantification to be conducted on a uniform flattened population of cells within the S-phase of the cell cycle. Findings of this study demonstrate the disruptive effects of ordered nanopits on adhesion formation and the role the conformation of nanofeatures plays in modulating these effects. Highly ordered arrays of nanopits resulted in decreased adhesion formation and a reduction in adhesion length, while introducing a degree of controlled disorder present in near-square arrays, was shown to increase focal adhesion formation and size. HOBs were also shown to be affected morphologicaly by the presence and conformation of nanopits. Ordered arrays affected cellular spreading, and induced an elongated cellular phenotype, indicative of increased motility, while near-square nanopit symmetries induced HOB spreading. It is postulated that nanopits affect osteoblast,substrate adhesion by directly or indirectly affecting adhesion complex formation, a phenomenon dependent on nanopit dimension and conformation. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:273,282, 2007 [source] Rhizocarpon calibration curve for the Aoraki/Mount Cook area of New Zealand,JOURNAL OF QUATERNARY SCIENCE, Issue 4 2005Thomas V. Lowell Abstract Development of Rhizocarpon growth curve from the Aoraki/Mount Cook area of New Zealand provides a means to assess Little Ice Age glacier behaviour and suggests approaches that have wider application. Employing a sampling strategy based on large populations affords the opportunity to assess which of various metrics (e.g. single largest, average of five largest, mean of an entire population) best characterise Rhizocarpon growth patterns. The 98% quantile from each population fitted with a quadric curve forms a reliable representation of the growth pattern. Since this metric does not depend on the original sample size, comparisons are valid where sample strategy must be adapted to local situations or where the original sample size differs. For the Aoraki/Mount Cook area a surface 100 years old will have a 98% quantile lichen diameter of 34.3,mm, whereas a 200-year-old surface will have a lichen diameter of 73.7,mm. In the Southern Alps, constraints from the age range of calibration points, the flattening of the quadric calibration curve and ecological factors limit the useful age range to approximately 250 years. Copyright © 2005 John Wiley & Sons, Ltd. [source] High-Temperature Hydroxylation and Surface Corrosion of 2/1-Mullite Single Crystals in Water Vapor EnvironmentsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2006Nadine Eils 2/1-mullite single crystal (001) plates with thicknesses between 0.9 and 1.9 mm were exposed for 1.5, 3, 6, and 12 h at 1670°C to a slowly flowing (100 mL/min) water-rich gas mixture (O2/H2O 80/20). Under the given experimental conditions, 2/1-mullite yielded significant amounts of structurally bound OH groups across the bulk and decomposition of the crystal surface on a micrometer scale. Decomposition products are (i) sodium-containing silicon-rich alumino silicate glass formed from melt and (ii) ,-alumina, which crystallizes within melt cavities. The crystal plates that are free of any OH absorption before the corrosion experiments show a steep increase in OH absorption intensity up to 3 h of corrosion and a flattening toward longer times of exposure. The evaluation of OH intensity profiles implies an effective diffusion coefficient DH in the range between 1.5 and 2.5 × 10,7 cm2/s. [source] Is peri-operative cortisol secretion related to post-operative cognitive dysfunction?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2005L. S. Rasmussen Background:, The pattern of cortisol secretion is influenced by surgery. As cortisol can adversely affect neuronal function, this may be an important factor in the development of post-operative cognitive dysfunction (POCD). We hypothesized that the incidence of POCD would be related to changes in cortisol level. Methods:, We studied 187 patients aged over 60 years undergoing major non-cardiac surgery with general or regional anaesthesia. Saliva cortisol levels were measured pre-operatively and at 1 day, 7 days and 3 months post-operatively in the morning (08.00 h) and in the afternoon (16.00 h) using salivettes. Cognitive function was assessed pre-operatively, on day 7 and at 3 months using four neuropsychological tests. POCD was defined as a combined Z score of greater than 1.96. Results:, After surgery, salivary cortisol concentrations increased significantly. POCD was detected in 18.8% of subjects at 1 week and in 15.2% after 3 months. The pre-operative ratios between the morning and afternoon cortisol concentrations (am/pm ratios) were 2.8 and 2.7 in patients with POCD at 1 week vs. those without POCD at 1 week, respectively. The am/pm ratios decreased significantly post-operatively to 1.9 and 1.6 at 1 week, respectively (P = 0.02 for both). In an analysis considering all am/pm ratios, it was found that the persistent flattening in am/pm ratio was significantly related to POCD at 1 week. Conclusion:, The pattern of diurnal variation in cortisol level was significantly related to POCD. Thus, circadian rhythm disturbance or metabolic endocrine stress could be an important mechanism in the development of cognitive dysfunction after major surgery. [source] The lobular expression of the rat asialoglycoprotein receptor is regulated at the posttranscriptional levelLIVER INTERNATIONAL, Issue 1 2005Mara Massimi Abstract: The purpose of this study was to define the distribution of the asialoglycoprotein receptor (ASGP-R) main peptide, rat hepatic lectin (RHL)-1, within the rat liver lobule and to investigate its possible modulation in physiological states characterised by marked changes of receptorial expression. In particular, we chose livers from rats partially hepatectomised or at the end of pregnancy, as models, respectively, of decreased or increased expression of the ASGP-R, and used the in situ hybridisation and immunocytochemistry techniques to analyse in parallel the lobular distributions of RHL-1 mRNA and protein. In normal rat liver, although the RHL-1 mRNA was homogeneously distributed, the RHL-1 peptide was predominantly localised on the surface of pericentral hepatocytes with a gradient of expression towards the periportal zone. This gradient of expression of RHL-1 peptide was reduced in regenerating livers, in which the positive stain was restricted to a few layers of cells around the central vein. In contrast, livers at the end of pregnancy showed an overall increase of the peptide with a concomitant flattening of the gradient across the liver plate. In all the conditions, we never observed important changes in the pattern of expression of the specific mRNA. These findings indicate that the distribution of ASGP-R is heterogeneous across the liver lobule, with a pattern of expression prevalently modulated at the posttranscriptional level. [source] Imaging and spectroscopy of ultrasteep spectrum radio sources,MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2007Carlos G. Bornancini ABSTRACT We present a sample of 40 ultrasteep spectrum (USS; ,,, 1.3, S,,,,) radio sources selected from the Westerbork in the Southern Hemisphere (WISH) catalogue. The USS sources have been imaged in K band at the Cerro Tololo Inter-American Observatory (CTIO) and with the Very Large Telescope (VLT) at Cerro Paranal. We also present VLT, Keck and William Herschel Telescope (WHT) optical spectroscopy of 14 targets selection from four different USS samples. For 12 sources, we have been able to determine the redshifts, including four new radio galaxies at z > 3. We find that most of our USS sources have predominantly small (<6 arcsec) radio sizes and faint magnitudes (K, 18). The mean K -band counterpart magnitude is . The expected redshift distribution estimated using the Hubble K,z diagram has a mean of , which is higher than the predicted redshift obtained for the Sydney University Molonglo Sky Survey,NRAO VLA Sky Survey (SUMSS,NVSS) sample and the expected redshift obtained in the 6C** survey. The compact USS sample analysed here may contain a higher fraction of galaxies which are high redshift and/or are heavily obscured by dust. Using the 74, 352 and 1400 MHz flux densities of a subsample, we construct a radio colour,colour diagram. We find that all but one of our USS sources have a strong tendency to flatten below 352 MHz. We also find that the highest redshift source from this paper (at z= 3.84) does not show evidence for spectral flattening down to 151 MHz. This suggests that very low frequency selected USS samples will likely be more efficient to find high redshift galaxies. [source] Turbulent gas motions in galaxy cluster simulations: the role of smoothed particle hydrodynamics viscosityMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2005K. Dolag ABSTRACT Smoothed particle hydrodynamics (SPH) employs an artificial viscosity to properly capture hydrodynamic shock waves. In its original formulation, the resulting numerical viscosity is large enough to suppress structure in the velocity field on scales well above the nominal resolution limit, and to damp the generation of turbulence by fluid instabilities. This could artificially suppress random gas motions in the intracluster medium (ICM), which are driven by infalling structures during the hierarchical structure formation process. We show that this is indeed the case by analysing results obtained with an SPH formulation where an individual, time-variable viscosity is used for each particle, following a suggestion by Morris & Monaghan. Using test calculations involving strong shocks, we demonstrate that this scheme captures shocks as well as the original formulation of SPH, but, in regions away from shocks, the numerical viscosity is much smaller. In a set of nine high-resolution simulations of cosmological galaxy cluster formation, we find that this low-viscosity formulation of SPH produces substantially higher levels of turbulent gas motions in the ICM, reaching a kinetic energy content in random gas motions (measured within a 1-Mpc cube) of up to 5,30 per cent of the thermal energy content, depending on cluster mass. This also has significant effects on radial gas profiles and bulk cluster properties. We find a central flattening of the entropy profile and a reduction of the central gas density in the low-viscosity scheme. As a consequence, the bolometric X-ray luminosity is decreased by about a factor of 2. However, the cluster temperature profile remains essentially unchanged. Interestingly, this tends to reduce the differences seen in SPH and adaptive mesh refinement simulations of cluster formation. Finally, invoking a model for particle acceleration by magnetohydrodynamics waves driven by turbulence, we find that efficient electron acceleration and thus diffuse radio emission can be powered in the clusters simulated with the low-viscosity scheme provided that more than 5,10 per cent of the turbulent energy density is associated with fast magneto-sonic modes. [source] GRS 1915+105: the distance, radiative processes and energy-dependent variabilityMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2005Andrzej A. Zdziarski ABSTRACT We present an exhaustive analysis of five broad-band observations of GRS 1915+105 in two variability states, , and ,, observed simultaneously by the Proportional Counter Array (PCA) and High-Energy X-ray Timing Experiment (HEXTE) detectors aboard the Rossi X-ray Timing Explorer, and the Oriented Scintillation Spectrometer Experiment (OSSE) detector aboard the Compton Gamma-ray Observatory. We find all the spectra well fitted by Comptonization of disc blackbody photons, with very strong evidence for the presence of a non-thermal electron component in the Comptonizing plasma. Both the energy and the power spectra in the , state are typical of the very high/intermediate state of black hole binaries. The spectrum of the , state is characterized by a strong blackbody component Comptonized by thermal electrons and a weak non-thermal tail. We then calculate rms spectra (fractional variability as functions of energy) for the PCA data. We accurately model the rms spectra by coherent superposition of variability in the components implied by the spectral fits, namely a less variable blackbody and more variable Comptonization. The latter dominates at high energies, resulting in a flattening of the rms at high energies in most of the data. This is also the case for the spectra of the quasi-periodic oscillations present in the , state. Then, some of our data require a radial dependence of the rms of the disc blackbody. We also study the distance to the source, and find d, 11 kpc as the most likely value, contrary to a recent claim of a much lower value. [source] XMM,Newton observations of GB B1428+4217: confirmation of intrinsic soft X-ray absorptionMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2004M. A. Worsley ABSTRACT We report the results of XMM,Newton observations of the X-ray bright, radio-loud blazar GB B1428+4217 at a redshift of z= 4.72. We confirm the presence of soft X-ray spectral flattening at energies ,0.7 keV as reported in previous ROSAT and BeppoSAX observations. At hard X-ray energies, the spectrum is consistent with a power law, although we find that the spectral slope varied between both XMM,Newton observations and it is also significantly different from that reported previously. Whilst we cannot rule out intrinsic cold absorption to explain the spectral depression, we favour a dust-free warm absorber. Cold absorption requires a column density ,1.4,1.6 × 1022 cm,2, whilst a warm absorber could have up to ,1023 cm,2 and an ionization parameter ,102. The spectrum of GB B1428+4217 shows remarkable parallels with that of the z= 4.4 blazar PMN J0525,3343, in which the available evidence is also most consistent with a warm absorber model. [source] Stellar populations and surface brightness fluctuations: new observations and modelsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2001John P. Blakeslee We investigate the use of surface brightness fluctuations (SBF) measurements in optical and near-IR bandpasses for both stellar population and distance studies. New V -band SBF data are reported for five galaxies in the Fornax cluster and combined with literature data to define a V -band SBF distance indicator, calibrated against Cepheid distances to the Leo group and the Virgo and Fornax clusters. The colour dependence of the V -band SBF indicator is only ,15 per cent steeper than that found for the I band, and the mean ,fluctuation colour' of the galaxies is We use new stellar population models, based on the latest Padua isochrones transformed empirically to the observational plane, to predict optical and near-IR SBF magnitudes and integrated colours for a wide range of population ages and metallicities. We examine the sensitivity of the predicted SBF,colour relations to changes in the isochrones, stellar transformations, and initial mass function. The new models reproduce fairly well the weak dependence of V and I SBF in globular clusters on metallicity, especially if the more metal-rich globulars are younger. Below solar metallicity, the near-IR SBF magnitudes depend mainly on age, while the integrated colours depend mainly on metallicity. This could prove a powerful new approach to the age,metallicity degeneracy problem; near-IR SBF observations of globular clusters would be an important test of the models. The models also help in understanding the and fluctuation colours of elliptical galaxies, with much less need for composite stellar populations than in previous models. However, in order to obtain theoretical calibrations of the SBF distance indicators, we combine the homogeneous population models into composite models and select out those ones with fluctuation colours consistent with observations. We are able to reproduce the observed range of elliptical galaxy colours, the slopes of the V and I SBF distance indicators against (fainter SBF in redder populations), and the flattening of the I -band relation for The models also match the observed slope of I -band SBF against the Mg2 absorption index and explain the steep colour dependence found by Ajhar et al. for the HST/WFPC2 F814W-band SBF measurements. In contrast to previous models, ours predict that the near-IR SBF magnitudes will also continue to grow fainter for redder populations. The theoretical V -band SBF zero-point predicted by these models agrees well with the Cepheid-calibrated V -band empirical zero-point. However, the model zero-point is 0.15,0.27 mag too faint in the I band and 0.24,0.36 mag too faint in K. The zero-points for the I band (empirically the best determined) would come into close agreement if the Cepheid distance scale were revised to agree with the recent dynamical distance measured to NGC 4258. We note that the theoretical SBF calibrations are sensitive to the uncertain details of stellar evolution, and conclude that the empirical calibrations remain more secure. However, the sensitivity of SBF to these finer details potentially makes it a powerful, relatively unexploited, constraint for stellar evolution and population synthesis. [source] Two measures of the shape of the dark halo of the Milky WayMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2000Rob P. Olling In order to test the reliability of determinations of the shapes of dark-matter haloes of the galaxies, we have made such measurements for the Milky Way by two independent methods. First, we have combined the measurements of the overall mass distribution of the Milky Way derived from its rotation curve and the measurements of the amount of dark matter in the solar neighbourhood obtained from stellar kinematics to determine the flattening of the dark halo. Secondly, we have used the established technique based on the variation in thickness of the Milky Way's H i layer with radius: by assuming that the H i gas is in hydrostatic equilibrium in the gravitational potential of a galaxy, one can use the observed flaring of the gas layer to determine the shape of the dark halo. These techniques are found to produce a consistent estimate for the flattening of the dark-matter halo, with a shortest-to-longest axis ratio of q,0.8, but only if one adopts somewhat non-standard values for the distance to the Galactic centre, R0, and the local Galactic rotation speed, ,0. For consistency, one requires values of R0,7.6 kpc and ,0,190 km s,1. The results depend on the Galactic constants because the adopted values affect both distance measurements within the Milky Way and the shape of the rotation curve, which, in turn, alter the inferred halo shape. Although differing significantly from the current IAU-sanctioned values, these upper limits are consistent with all existing observational constraints. If future measurements confirm these lower values for the Galactic constants, then the validity of the gas-layer-flaring method will be confirmed. Further, dark-matter candidates such as cold molecular gas and massive decaying neutrinos, which predict very flat dark haloes with q,0.2, will be ruled out. Conversely, if the Galactic constants were found to be close to the more conventional values, then there would have to be some systematic error in the methods for measuring dark halo shapes, so the existing modelling techniques would have to be viewed with some scepticism. [source] Polarized diffuse emission at 2.3 GHz in a high Galactic latitude areaMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY: LETTERS (ELECTRONIC), Issue 1 2005E. Carretti ABSTRACT Polarized diffuse emission observations at 2.3 GHz in a high Galactic latitude area are presented. The 2°× 2° field, centred at (,= 5h, ,=,49°), is located in the region observed by the BOOMERanG experiment. Our observations were carried out with the Parkes radio telescope, and represent the highest frequency detection to date in a low-emission area. Because of the weaker Faraday rotation effect, the high frequency allows an estimate of the Galactic synchrotron contamination of the cosmic microwave background polarization (CMBP) which is more reliable than that achieved at 1.4 GHz. We find that the angular power spectra of the E - and B -modes have slopes of ,E=,1.46 ± 0.14 and ,B=,1.87 ± 0.22, indicating a flattening with respect to 1.4 GHz. Extrapolated up to 32 GHz, the E -mode spectrum is about three orders of magnitude lower than that of the CMBP, allowing a clean detection even at this frequency. The best improvement concerns the B -mode, for which our single-dish observations provide the first estimate of the contamination on angular scales close to the CMBP peak (about 2°). We find that the CMBP B -mode should be stronger than the synchrotron contamination at 90 GHz for models with tensor-to-scalar perturbation ratio T/S > 0.01. This low level could move down to 60,70 GHz the optimal window for CMBP measurements. [source] Novel Aspects of Intrinsic and Extrinsic Aging of Human Skin: Beneficial Effects of Soy Extract,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2005Kirstin M. Südel ABSTRACT Biochemical and structural changes of dermal connective tissue substantially contribute to the phenotype of aging skin. To study connective tissue metabolism with respect to ultraviolet (UV) exposure, we performed an in vitro (human dermal fibroblasts) and an in vivo complementary DNA array study in combination with protein analysis in young and old volunteers. Several genes of the collagen metabolism such as Collagen I, III and VI as well as heat shock protein 47 and matrix metalloproteinase-1 are expressed differentially, indicating UV-mediated effects on collagen expression, processing and degradation. In particular, Collagen I is time and age dependently reduced after a single UV exposure in human skin in vivo. Moreover, older subjects display a lower baseline level and a shorter UV-mediated increase in hyaluronan (HA) levels. To counteract these age-dependent changes, cultured fibroblasts were treated with a specific soy extract. This treatment resulted in increased collagen and HA synthesis. In a placebo-controlled in vivo study, topical application of an isoflavone-containing emulsion significantly enhanced the number of dermal papillae per area after 2 weeks. Because the flattening of the dermal-epidermal junction is the most reproducible structural change in aged skin, this soy extract appears to rejuvenate the structure of mature skin. [source] WST11, A Novel Water-soluble Bacteriochlorophyll Derivative; Cellular Uptake, Pharmacokinetics, Biodistribution and Vascular-targeted Photodynamic Activity Using Melanoma Tumors as a Model,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005Ohad Mazor ABSTRACT WST11 is a novel negatively charged water-soluble palladiumbacteriochlorophyll derivative that was developed for vascular-targeted photodynamic therapy (VTP) in our laboratory. The in vitro results suggest that WST11 cellular uptake, clearance and phototoxicity are mediated by serum albumin trafficking. In vivo, WST11 was found to clear rapidly from the circulation (t1/2= 1.65 min) after intravenous bolus injection in the mouse, whereas a longer clearance time (t1/2= 7.5 min) was noted in rats after 20 min of infusion. The biodistribution of WST11 in mouse tissues indicates hepatic clearance (t1/2= 20 min), with minor (kidney, lung and spleen) or no intermediary accumulation in other tissues. As soon as 1 h after injection, WST11 had nearly cleared from the body of the mouse, except for a temporal accumulation in the lungs from which it cleared within 40 min. On the basis of these results, we set the VTP protocol for a short illumination period (5 min), delivered immediately after WST11 injection. On subjecting M2R melanoma xenografts to WST11-VTP, we achieved 100% tumor flattening at all doses and a 70% cure with 9 mg/kg and a light exposure dose of 100 mW/cm2. These results provide direct evidence that WST11 is an effective agent for VTP and provide guidelines for further development of new candidates. [source] Bending in HVPE GaN free-standing films: effects of laser lift-off, polishing and high-pressure annealingPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2006T. Paskova Abstract We have studied the effects of laser lift-off and polishing processes on the bending of free-standing HVPE grown GaN thick films. Their structural characteristics were accessed by reciprocal space mapping and lattice parameters measurements as well as by Raman scattering and photoluminescence. The in-plane strain difference between the two faces was found to have determining effect on the bending of the free-standing films. Removing the high-defect-density near-interface region either by melting caused by laser lift-off, or by polishing, or by point defects dissociation caused by high-pressure annealing was found to lead to flattening of the strain distribution along the film thickness and a significant reduction of the bending of the free-standing films. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Brain size and the human cranial base: A prenatal perspectiveAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2002Nathan Jeffery Abstract Pivotally positioned as the interface between the neurocranium and the face, the cranial base has long been recognized as a key area to our understanding of the origins of modern human skull form. Compared with other primates, modern humans have more coronally orientated petrous bones and a higher degree of basicranial flexion, resulting in a deeper and wider posterior cranial fossa. It has been argued that this derived condition results from a phylogenetic increase in the size of the brain and its subcomponents (infra- and supratentorial volumes) relative to corresponding lengths of the cranial base (posterior and anterior, respectively). The purpose of this study was to test such evolutionary hypotheses in a prenatal ontogenetic context. We measured the degree of basicranial flexion, petrous reorientation, base lengths, and endocranial volumes from high-resolution magnetic resonance images (hrMRI) of 46 human fetuses ranging from 10,29 weeks of gestation. Bivariate comparisons with age revealed a number of temporal trends during the period investigated, most notable of which were coronal rotation of the petrous bones and basicranial retroflexion (flattening). Importantly, the results reveal significant increases of relative endocranial sizes across the sample, and the hypotheses therefore predict correlated variations of cranial base flexion and petrous orientation in accordance with these increases. Statistical analyses did not yield results as predicted by the hypotheses. Thus, the propositions that base flexion and petrous reorientation are due to increases of relative endocranial sizes were not corroborated by the findings of this study, at least for the period investigated. Am J Phys Anthropol 118:324,340, 2002. © 2002 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||