Dichotomous behavior of polymer melts in isothermal melt spinning

Isothermal melt spinning experiments have been conducted using two polyethylene melts of low density (LDPE) and high density (HDPE) to produce steady state spinline profiles. The data revealed the threadline extensional viscosity exhibiting a contrasting picture : extension thickening behavior for LDPE and extension thinning one for HDPE. A White-Metzner model having a strain rate-dependent relaxation time was then found to be able to simulate this dichotomy in melt spinning fairly well: the fluids whose relaxation times have smaller strain rate-dependence can fit LDPE data with extension thickening extensional viscosity whereas the fluids whose relaxation times have larger strain rate-dependence can fit HDPE data with extension thinning extensional viscosity. This dichotomous nature of viscoelastic fluids is also believed to be able to explain other similar contrasting phenomena exhibited by polymer melts, such as vortex/no vortex in entry flows, cohesive/ductile fracture modes in extension, and more/less stable draw resonance than Newtonian fluids.     

Prevalence of serologic markers of HBV, HDV, HCV and HIV in non-injection drug users compared to injection drug users in Gran Canaria, Spain

Von Hippel-Lindau disease (VHL) is an autosomal dominant tumour syndrome caused by germline mutations of the VHL tumour suppressor gene located on chromosome 3p25-26. In VHL tumours may occur in 14 different target organs, including the eye. Retinal angiomas are considered the first manifestation of VHL disease in 43% of cases, and the cumulative probability of developing a retinal angioma in one or both eyes rises during each decade of life, reaching 80% for patients over 80 years old. Since 1976 patients with VHL at the University Hospital of Utrecht and their at-risk relatives have been screened periodically by a multidisciplinary team. Long-term follow-up ophthalmological data were analysed with special attention to natural course and results of treatment. In addition, we looked for a genotype-phenotype correlation. Retinal angiomas were found in all families. In one large family with a missense mutation (V170D) of the VHL gene, in which the complete spectrum of visceral- and central nervous system (CNS) features of VHL is present, macular, parapapillary, optic disc and ora serrata angiomas were also found. In general, however, a clear-cut genotype-phenotype correlation could not be found. Only early detection and treatment of peripheral retinal angiomas can be expected to decrease the percentage of patients with decreased visual acuity. Therefore, early detection and treatment of these tumours is of paramount importance. Ophthalmological screening of patients and persons at risk should start as early as possible. In patients with apparently sporadic retinal angiomas it is advisable to perform germline DNA analysis, since the risk of developing VHL is high, especially if the angiomas are bilateral, or unilateral and multifocal, if the patient is young, or if there is a family history suggestive of VHL.     

Abnormalities in plasma and red blood cell fatty acid profiles of patients with colorectal cancer

Intravenous injection of stearoyl vanillylamide (C18-VA), a nonpungent capsaicin (CAP) analog, enhances adrenaline secretion significantly and as effectively as CAP in rats. Because swimming capacity was enhanced by CAP in mice due to CAP-induced adrenal catecholamine secretion, we investigated the effects of oral administration of C18-VA on swimming capacity using an adjustable-current water pool. Male Std ddY 6-wk-old mice were fed a commercial diet for this study and one group was orally administered C18-VA via a stomach tube. Treated mice were able to swim longer before exhaustion than the control mice (62.9 +/- 5.6 vs. 49.6 +/- 7. 0 min, P < 0.05). The swimming capacity of two groups administered C18-VA (0.02 and 0.033 mmol/kg) was significantly greater than that of those administered vehicle alone, (P < 0.05). Substance P concentration in cerebrospinal fluid, which is involved in pain transmission and is the first direct measure of pungency, was not affected by C18-VA administration. In an experiment examining the effects of C18-VA on serum adrenaline concentration, adrenaline was significantly greater in C18-VA treated mice than in controls at 2-h post-dose (C18-VA group, 26.09 +/- 2.82; control group 13.29 +/- 0. 96 microg/L, P < 0.01). In a separate study free fatty acids in serum were elevated in treated mice at 2-h post-dose (P < 0.01). While serum glucose concentration was not affected. These results suggest that C18-VA increased swimming capacity of mice via adrenaline release, independent of pungency. In addition, the present study suggests the usefulness of its application to humans.     

Epidemiology of peptic ulcer disease in cirrhotic patients: role of Helicobacter pylori infection

OBJECTIVE: The aim of this study was to investigate the clinical and epidemiological factors associated with the appearance of peptic ulcer in patients with cirrhosis and, in particular, the role of Helicobacter pylori infection. METHODS: A total of 201 of 220 consecutive patients included in a prospective study that aimed to evaluate the effect of dietary intervention on cirrhotic complications and survival underwent upper gastrointestinal endoscopy. At entry, an epidemiological and clinical questionnaire was completed and the presence of peptic ulcer disease or esophageal varices at endoscopy was prospectively collected. Sera were obtained and stored at -70 degrees C until analyzed, being tested afterward for Helicobacter pylori antibodies using a commercial ELISA kit. RESULTS: Eleven of 201 patients had borderline anti-Helicobacter pylori IgG titers and were excluded from further analysis. In the remaining 190 patients, point prevalence of peptic ulcer was 10.5% and lifetime prevalence 24.7%. Multivariate analysis selected male sex (OR 2.3; 95%CI 1.09-4.89) and Helicobacter pylori seropositivity (OR: 1.7, 95%CI 1.02-2.81) as the variables independently related to peptic ulcer disease. CONCLUSIONS: Male sex and seropositivity for Helicobacter pylori are the major risk factors for peptic ulcer in cirrhosis.     

Neural network’s selection of color in UI design of social software

Neural Computing and Applications - In recent years, the design of social software UI has become a design research focus in the field of design. Color affects many factors in UI design. However,...     

Performance of TZCD-MBOK watermarking scheme in T-DMB systems

Recently, watermarking based data transmission techniques using terrestrial digital TV signal have been proposed since they are also cost-free and can overcome the limitations of GPS. However, in the previous watermarking based methods, the detection accuracy is low and additional data rate is too low. Thus, we propose the throughput enhancement method by employing the TZCD-MBOK watermarking technique in T-DMB system. By applying the proposed scheme to T-DMB, it allows additional data transmission for disaster broadcasting and improves efficiency of data transmission in shadow region and indoor to mobile environment through watermarking spread code. From the simulation results, we confirm the proposed watermarking scheme affected on the existing T-DMB signal. Moreover, it was also confirmed that the system capacity increases as the power of additional watermarking signal rose. The results of the paper can be applied to wireless multimedia digital broadcasting systems.     

Minimal-drift heading measurement using a MEMS gyro for mobile robots: Fused with odometry

To achieve the goal of low-cost MEMS gyros for the precise self-localization of mobile robots, this paper presents a simple, yet effective method to minimize drifts on the heading angle by combining measurements from a gyro with measurements from wheel encoders (odometry). The main idea of the proposed approach is to estimate the accuracy of both sensors as a function of the actual maneuver being carried out, and then the output of both sensors are fused by the complementary filter taking into account the maneuvering conditions. The proposed method is applied to a mobile robot and the experimental data demonstrate the effectiveness of this approach.     

An investigation into vehicle rollover prevention by coordinated control of active anti-roll bar and electronic stability program

This paper presents a method for designing a controller that uses an active anti-roll bar (AARB) and an electronic stability program (ESP) for rollover prevention. ESP with longitudinal speed control (LSC) can carry out active braking to reduce vehicle speed and lateral acceleration to prevent a rollover. To enhance the rollover prevention capability of the ESP, an AARB is adopted. The controller for the AARB was designed based on linear quadratic (LQ) static output feedback (SOF) control methodology, which attenuates the effect of lateral acceleration on the roll angle and roll rate by control of the suspension stroke and the tire deflection of the vehicle. Although this AARB significantly increases ride comfort and rollover prevention, it has a drawback — the vehicle loses its maneuverability. Therefore, the ESP with LSC is used to overcome this drawback. Simulations showed that the proposed method was effective in preventing a rollover.