The role of plug design in determining wall thickness distribution in thermoforming

An experimental investigation has been carried out into the effects of changes in plug design on the wall thickness distribution of thermoformed products. Plugs were machined with a series of geometrical variations and their effects on the process were measured. The overall results show that the plug has a crucial role in controlling the wall thickness distribution in thermoforming. Larger plugs tend to distribute more material to the base of the product, but the introduction of a small sidewall taper, base radius, or a reduction in plug diameter tend to lead to more balanced distributions. However, larger changes in any of the variables tend to destroy these benefits. It has also been demonstrated that the frictional and thermal properties of the plug are important in determining the deformation response of the sheet material. There is a clear evidence of slip in the sheet during plug contact and, although the cooling effect of the plug appears to be minimal, cooling in the highly deformed regions away from the plug appears to be a significant factor.

Reduction of proton acceleration in high-intensity laser interaction with solid two-layer targets

Reduction of proton acceleration in the interaction of a high-intensity, picosecond laser with a 50-mu m aluminum target was observed when 0.1-6 mu m of plastic was deposited on the back surface (opposite side of the laser). The maximum energy and number of energetic protons observed at the back of the target were greatly reduced in comparison to pure aluminum and plastic targets of the same thickness. This is attributed to the effect of the interface between the layers. Modeling of the electron propagation in the targets using a hybrid code showed strong magnetic-field generation at the interface and rapid surface heating of the aluminum layer, which may account for the results. (c) 2006 American Institute of Physics.

Spatial statistics to estimate peat thickness using airborne radiometric data

Soil carbon stores are a major component of the annual returns required by EU governments to the Intergovernmental Panel on Climate Change. Peat has a high proportion of soil carbon due to the relatively high carbon density of peat and organic-rich soils. For this reason it has become increasingly important to measure and model soil carbon stores and changes in peat stocks to facilitate the management of carbon changes over time. The approach investigated in this research evaluates the use of airborne geophysical (radiometric) data to estimate peat thickness using the attenuation of bedrock geology radioactivity by superficial peat cover. Remotely sensed radiometric data are validated with ground peat depth measurements combined with non-invasive geophysical surveys. Two field-based case studies exemplify and validate the results. Variography and kriging are used to predict peat thickness from point measurements of peat depth and airborne radiometric data and provide an estimate of uncertainty in the predictions. Cokriging, by assessing the degree of spatial correlation between recent remote sensed geophysical monitoring and previous peat depth models, is used to examine changes in peat stocks over time. The significance of the coregionalisation is that the spatial cross correlation between the remote and ground based data can be used to update the model of peat depth. The result is that by integrating remotely sensed data with ground geophysics, the need is reduced for extensive ground-based monitoring and invasive peat depth measurements. The overall goal is to provide robust estimates of peat thickness to improve estimates of carbon stocks. The implications from the research have a broader significance that promotes a reduction in the need for damaging onsite peat thickness measurement and an increase in the use of remote sensed data for carbon stock estimations.

Corneal hysteresis is correlated with reduction in axial length after trabeculectomy.

BACKGROUND: We sought to determine whether corneal biomechanical parameters are predictive of reduction in axial length after anti-metabolite trabeculectomy. METHODS: Chinese subjects undergoing trabeculectomy with mitomycin C by a single experienced surgeon underwent the following measurements: Corneal hysteresis (CH, Ocular Response Analyzer, Reichert Ophthalmic Instruments), Goldmann intra-ocular pressure (IOP), central corneal thickness (CCT) and axial length (AL, IOLMaster, Carl Zeiss Meditec, Dublin, CA) were measured pre-operatively, and AL, CH and IOP were measured 1 day and 1 week post-operatively. RESULTS: Mean age of 31 subjects was 52.0 ± 15.2 years, and 15 (48.4%) were female. The mean pre-operative IOP of 21.4 ± 9.3 mmHg was reduced to 8.2 ± 4.6 mmHg 1 day and 11.0 ± 4.4 mmHg 1 week post-operatively (p < 0.001). AL declined from 22.99 ± 0.90 to 22.76 ± 0.87 mm at 1 day and 22.74 ± 0.9 mm at 1 week; 30/31 (%) eyes had a decline in AL (p < 0.001, sign test). In multivariate linear regression models including post-operative data from 1 day and 1 week, greater decline in Goldmann IOP (p < 0.0001, greater pre-op axial length (p < 0.001) and lower pre-operative CH (p = 0.03), were all associated with greater decline in post-operative axial length. CONCLUSIONS: Eyes with lesser ability of the ocular coat to absorb energy (lower CH) had significantly greater decrease in axial length after trabeculectomy-induced IOP-lowering.

Experimental measuring procedure for the friction torque in rolling bearings

The reduction of the power loss generated in mechanical transmissions and the use of low friction biodegradable lubricants has been attracting considerable attention in recent times. Therefore, it is necessary to develop methods to test and evaluate the performance of such lubricants and compare them with conventional ones. In this sense, a Four-Ball Machine was modified allowing the test of rolling bearings. A 51107 thrust ball bearing was used to test two different greases and the corresponding base oils. Friction torque and operating temperatures were continuously monitored to quantify the power loss and the heat evacuation for each lubricant tested. Copyright © 2010 John Wiley & Sons, Ltd.

Frequency tunable metallo–dielectric structure for backscattering reduction

Electromagnetic scattering behaviour of a superstrate loaded metallo– dielectric structure based on Sierpinski carpet fractal geometry is reported. The results indicate that the frequency at which backscattering is minimum can be tuned by varying the thickness of the superstrate. A reduction in backscattered power of 44 dB is obtained simultaneously for both TE and TM polarisations of the incident field.

Experimental model of the interfacial instability in aluminium reduction cells

A solution has been found to the long-standing problem of experimental modelling of the interfacial instability in aluminium reduction cells. The idea is to replace the electrolyte overlaying molten aluminium with a mesh of thin rods supplying current down directly into the liquid metal layer. This eliminates electrolysis altogether and all the problems associated with it, such as high temperature, chemical aggressiveness of media, products of electrolysis, the necessity for electrolyte renewal, high power demands, etc. The result is a room temperature, versatile laboratory model which simulates Sele-type, rolling pad interfacial instability. Our new, safe laboratory model enables detailed experimental investigations to test the existing theoretical models for the first time.

A reduction of CETP activity, not an increase, is associated with modestly impaired postprandial lipemia and increased HDL-Cholesterol in adult asymptomatic women

Background: The relationship between CETP and postprandial hyperlipemia is still unclear. We verified the effects of varying activities of plasma CETP on postprandial lipemia and precocious atherosclerosis in asymptomatic adult women. Methods: Twenty-eight women, selected from a healthy population sample (n = 148) were classified according to three CETP levels, all statistically different: CETP deficiency (CETPd <= 4.5%, n = 8), high activity (CETPi >= 23.8, n = 6) and controls (CTL, CETP >= 4.6% and <= 23.7%, n = 14). After a 12 h fast they underwent an oral fat tolerance test (40 g of fat/m(2) of body surface area) for 8 hours. TG, TG-rich-lipoproteins (TRL), cholesterol and TRL-TG measurements (AUC, AUIC, AR, RR and late peaks) and comparisons were performed on all time points. Lipases and phospholipids transfer protein (PLTP) were determined. Correlation between carotid atherosclerosis (c-IMT) and postprandial parameters was determined. CETP TaqIB and I405V and ApoE-epsilon 3/epsilon 2/epsilon 4 polymorphisms were examined. To elucidate the regulation of increased lipemia in CETPd a multiple linear regression analysis was performed. Results: In the CETPi and CTL groups, CETP activity was respectively 9 and 5.3 higher compared to the CETPd group. Concentrations of all HDL fractions and ApoA-I were higher in the CETPd group and clearance was delayed, as demonstrated by modified lipemia parameters (AUC, AUIC, RR, AR and late peaks and meal response patterns). LPL or HL deficiencies were not observed. No genetic determinants of CETP deficiency or of postprandial lipemia were found. Correlations with c-IMT in the CETPd group indicated postprandial pro-atherogenic associations. In CETPd the regression multivariate analysis (model A) showed that CETP was largely and negatively predicted by VLDL-C lipemia (R(2) = 92%) and much less by TG, LDL-C, ApoAI, phospholipids and non-HDL-C. CETP (model B) influenced mainly the increment in ApoB-100 containing lipoproteins (R(2) = 85% negatively) and phospholipids (R(2) = 13%), at the 6(th)h point. Conclusion: The moderate CETP deficiency phenotype included a paradoxically high HDL-C and its sub fractions (as earlier described), positive associations with c-IMT, a postprandial VLDL-C increment predicting negatively CETP activity and CETP activity regulating inversely the increment in ApoB100-containing lipoproteins. We hypothesize that the enrichment of TG content in triglyceride-rich ApoB-containing lipoproteins and in TG rich remnants increases lipoproteins` competition to active lipolysis sites, reducing their catabolism and resulting on postprandial lipemia with atherogenic consequences.

A Cost Model for the Effect of Setup Time Reduction in Stainless Steel Strip Production

Setup time reduction facilitate the flexibility needed for just-in-time production. An integrated steel mill with meltshop, continuous caster and hot rolling mill is often operated as decoupled processes. Setup time reduction provides the flexibility needed to reduce buffering, shorten lead times and create an integrated process flow. The interdependency of setup times, process flexibility and integration were analysed through system dynamics simulation. The results showed significant reductions of energy consumption and tied capital. It was concluded that setup time reduction in the hot strip mill can aid process integration and hence improve production economy while reducing environmental impact.

FeNbP in ultra-low carbon Nb-added steel containing high P

Precipitation of FeTiP is reported to occur in Ti-added IF steels containing high P during thermomechanical processing. An ultra-low carbon (ULC) Nb-added steel ingot containing a higher P content (< 0.8 wt-%) was produced via aluminothermic reduction of Fe2O3 followed by double electron beam melting (EBM). FeNbP coarse precipitates were observed in the as-cast microstructure. After soaking at 1050C for 1 h, the plate was hot rolled from 31 mm down to 7 mm in thickness (total reduction of 77%). During cold rolling of these hot bands we observed embrittlement. We believe that this embrittlement can be attributed to the presence of the FeNbP precipitates. Light optical and scanning electron microscopy (SEM/EDS) were used to characterize the microstructure of this ULC steel. (C) 2000 Elsevier B.V. All rights reserved.

Reduction of podocytes number in late diabetic alloxan nephropathy: prevention by glycemic control

OBJETIVO: Avaliar o número de podócitos e espessamento da membrana basal glomerular (MBG) em ratos diabéticos com e sem controle glicêmico com 6 e 12 meses da indução. MÉTODOS: 100 ratos Wistar com 200-300g compuseram 6 grupos: Normal (N6, N12 - 25 animais) Diabético (D6,D12 - 25 animais) e diabético tratado com insulina 1,8 a 3,0 U/Kg e acarbose misturada a ração (50g para cada 100g de ração) (DT6 e DT12 - 25 animais). Aloxana foi ministrada via endovenosa na dose de 42mg/Kg. Peso, ingestão hídrica e diurese de 24 horas e glicemia e glicosúria foram determinados antes da inoculação, 7 e 14 dias após e mensalmente. No 14ª dia foi iniciado o tratamento. Três grupos de animais (N6, D6 e DT6) foram sacrificados no 6° mês e três grupos (N12, D12 e DT12), no 12ª mês sendo o tecido renal processado para estudo à microscopia eletrônica. RESULTADOS: A glicemia dos animais DT6 e DT12 diferiram significativamente, dos ratos D6 e D12, e não diferiram dos grupos N6 e N12. O número de podócitos do grupo DT6 não diferiu de N6 e D6 (mediana=11); o número de podócitos de DT12 (mediana=11) diferiu de D12 (mediana=8) e não diferiu de N12 (mediana=11). O espessamento da MBG de D6 (0,18 micrômetros) foi menor que D12 (0,29 micrômetros); de DT6 (0,16 micrômetros) foi menor que D6 (0,18 micrômetros) e de DT12 (0,26 micrômetros) foi menor que D12 (0,29 micrômetros). CONCLUSÃO: O controle da hiperglicemia preveniu o espessamento da MBG na nefropatia diabética aloxânica precoce (6 meses) e tardia (12 meses), e a diminuição do número de podócitos.

Effect of mangiferin on the development of periodontal disease: Involvement of lipoxin A(4), anti-chemotaxic action in leukocyte rolling

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Amoxicillin diminishes the thickness of the enamel matrix that is deposited during the secretory stage in rats

The use of amoxicillin during early childhood has been associated with molar incisor hypomineralization. The objective of this study was to determine whether the use of amoxicillin interferes with enamel development, during secretion and early mineralization stages. Fifteen pregnant rats were randomly assigned to three groups that received physiological solution (sham group), 100 mg/kg/day amoxicillin (A100G), and 500 mg/kg/day amoxicillin (A500G). After birth, the pups in each group received the same treatment until post-natal day 7 or 12. The upper first molars were analyzed histomorphometrical and immunostaining with amelogenin on day 7, and MMP-20 on day 12 was performed using a semiquantitative method (H-score). At 7 days, several vacuolar structures were observed in the ameloblasts in the A100G and A500G groups. A significant reduction of the enamel thickness (P < 0.001) was found in amoxicillin-treated rats compared with the sham group. Significant differences were not observed in enamel thickness (P > 0.05) between the groups of 12-day-old rats. Moreover, significant differences were not observed in the number of amelogenin- and MMP-20-immunolabeled ameloblasts (P > 0.05) between groups. The present results suggest that amoxicillin interferes with the initial stages of amelogenesis by causing structural changes in the ameloblasts and a reduction of the enamel matrix.

Laminar Displacement and Prelaminar Tissue Thickness Change after Glaucoma Surgery Imaged with Optical Coherence Tomography

PURPOSE. To study changes in lamina cribrosa position and prelaminar tissue thickness (PTT) after surgical IOP reduction in glaucoma patients. METHODS. Twenty-two patients (mean age, 71.4 years) were imaged with spectral domain optical coherence tomography (SD-OCT; 24 radial B-scans centered on the optic nerve head [ONH]) before trabeculectomy or tube shunt implantation. Follow up images were acquired 1 week, 1 month, 3 months, and 6 months postsurgery. Bruch's membrane opening (BMO), the internal limiting membrane (ILM) and the anterior laminar surface (ALS) were segmented in each radial scan with custom software. Surfaces were fitted to the ILM and ALS with the extracted three-dimesional coordinates. PTT was the distance between the ILM and ALS, perpendicular to a BMO reference plane. Serial postsurgical laminar displacement (LD), relative to the BMO reference plane, and changes in PTT were measured. Positive values indicated anterior LD. RESULTS. Mean (SD) presurgery IOP was 18.1 (6.5) mm Hg, and reduced by 4.7 (5.5), 2.4 (7.7), 7.0 (6.2), and 6.8 (7.5) mm Hg at 1 week, 1 month, 3 months, and 6 months postsurgery, respectively. At the four postsurgery time points, there was significant anterior LD (1.8 [9.5], -1.1 [8.9], 8.8 [20.2], and 17.9 [25.8] mu m) and PTT increase (1.7 [13.3], 2.4 [11.9], 17.4 [13.7], and 13.9 [18.6] mu m). LD was greater in ONHs with larger BMO area (P = 0.01) and deeper ALS (P = 0.04); however, PTT was not associated with any of the tested independent variables. CONCLUSIONS. Both anterior LD and thickening of prelaminar tissue occur after surgical IOP reduction in patients with glaucoma. (Invest Ophthalmol Vis Sci. 2012;53:5819-5826) DOI:10.1167/iovs.12-9924

Carotid plaque and intima-media thickness and the incidence of ischemic events in patients with atherosclerotic vascular disease

We aimed to evaluate whether carotid intima-media thickness (CIMT) or the presence of plaque can confer additional predictive value of future cardiovascular (CV) ischemic events in patients with pre-existing atherosclerotic vascular disease. We identified 2317 patients enrolled in the REduction of Atherothrombosis for Continued Health (REACH) registry who had atherosclerotic vascular disease and baseline CIMT measurements. The entire range of CIMT was divided into quartiles and the fourth quartile (? 1.5 mm) was defined as carotid plaque. Mean ± standard deviation baseline CIMT was 1.31 ± 0.65 mm. Associated CV ischemic events and vascular-related hospitalizations were evaluated over a 2-year follow-up. There was a positive increase in adjusted hazard ratios (HRs) for all-cause mortality (p = 0.04 for trend) and the quadruple endpoint (CV death, myocardial infarction (MI), stroke, hospitalization for CV events) with increasing quartiles of CIMT (p = 0.0008 for trend), which was mainly driven by the fourth quartile (carotid plaque). HRs for all-cause mortality, CV death, CV death/MI/stroke and the quadruple endpoint comparing the highest (carotid plaque) with the lowest CIMT quartile were 2.09 (95% CI, 1.07-4.10; p = 0.03); 2.49 (1.10-5.67; p = 0.03); 1.71 (1.10-2.67; p = 0.02); and 1.73 (1.31-2.27; p = 0.0001). In conclusion, our analyses suggest that the presence of carotid plaque, rather than the thickness of intima-media, appears to be associated with increased risk of CV morbidity and mortality, but confirmation of these findings in other population and prospective studies is required.