The hypertriglyceridemic waist phenotype is a predictor of elevated levels of small, dense LDL cholesterol

The hypertriglyceridemic waist (HTGW) phenotype (hypertriglyceridemia and increased waist circumference) has been proposed as an inexpensive tool to monitor individuals with the atherogenic metabolic triad, hyperinsulinemia, hyperapobetalipoproteinemia, and increased levels of small, dense LDL (sdLDL) particles. We assessed the association of the HTGW phenotype with the metabolic syndrome (MetSyn) and the atherogenic metabolic triad in inhabitants (n=260) of northwestern Greece attending the Outpatient Lipid Clinic of the University Hospital of loannina. The LDL subfractions were assessed using the Lipoprint LDL System. HTGW (+) individuals had a more adverse lipid and lipoprotein profile compared with HTGW (−) individuals. Moreover, HTGW (+) subjects had elevated levels of sdLDL-C, as well as decreased mean and peak LDL particle size compared with HTGW (−) subjects. To our knowledge, this is the first report documenting the sdLDL-C abnormality in HTGW (+) subjects. Among men (n=105), 52.3% of the MetSyn (+) individuals and 66.7% of the HTGW (+) individuals had the metabolic triad. Among women (n=155), the corresponding percentages were 42.3% and 50.0%. Only 22.2% and 10.6% of the Metsyn (−) subjects (men and women, respectively) and 19.6% and 15.2% of the HTGW (−) subjects (men and women, respectively) had the atherogenic metabolic triad. In conclusion, the HTGW (+) phenotype is associated with a hostile lipid profile that includes higher levels of sdLDL-C and decreased LDL particle size. The HTGW phenotype, compared with the MetSyn criteria, can provide an easy and inexpensive tool to monitor patients characterized by an adverse lipid and lipoprotein profile.     

Effects of phosphates and citrates on sediment formation in UHT goats' milk

Sediment formation was investigated during UHT treatment of goats' milk, subjected to indirect treatment at 140 degrees C for 2 s, with upstream homogenisation. Stabilisers evaluated were sodium hexametaphosphate (SHMP), trisodium citrate (TSC), disodium hydrogen orthophosphate (DSHP), and sodium dihydrogen orthophosphate (SDHP). With no added stabiliser, goats' milk produced a heavy sediment on UHT treatment. Addition of SDHP reduced pH, had little effect on ionic calcium and did not substantially reduce sediment. However, addition of SHMP, DSHP and TSC each reduced ionic calcium, increased ethanol stability and reduced sediment. Following stabiliser additions, there was a good correlation between ethanol stability and ionic calcium (R2=0.85) but not between ethanol stability and pH (R2=0.08). Overall, reducing ionic calcium reduced the amount of sediment formed for all these three stabilisers, although there was no single trend line between sediment formation and ionic calcium concentration. Sediment formation was not well correlated with pH for TSC or for SHMP, but it was for DSHP, making it the only stabiliser where sediment formation correlated well both with ionic calcium and pH, which might account for its effectiveness at higher ionic calcium levels. Sediment was much reduced when the temperature was reduced from 140 degrees C to 125 degrees C and 114 degrees C. There were no further changes in sediment on storage for two weeks. Analysis of the sediment showed that it was predominantly fat and protein, with a mass ratio ranging between 1.43:1 and 1.67:1. Its mineral content was usually less than 5% of dry weight. The maximum amounts of P and Ca were found to be 2.32% and 1.63%, respectively.     

Atmospheric plasma fluorination as a means to improve the mechanical properties of short-carbon fibre reinforced poly (vinylidene fluoride)

The impact of fluorination of carbon fibres on the properties of short fibre reinforced polyvinylidene fluoride (PVDF) composites was studied. As received and continuously atmospheric plasma fluorinated (APF) carbon fibres were cut to an average fibre length of 2 mm. Short fibre composites (SFC) containing 5, 10 and 15 wt.% carbon fibres were manufactured using a twin-screw mixer. Test specimens were produced by injection moulding. The mechanical properties of the SFC were studied using tensile and compression testing. As expected, the incorporation of short-carbon fibres into PVDF led to an increase in strength and stiffness. The tensile strength and Young’s modulus of the SFC containing APF-treated carbon fibres increased by up to 17% and 190%, respectively. Furthermore, the compressive strength and modulus of the SFC containing APF-treated carbon fibres also increased by 19% and 35%, respectively. APF of carbon fibres results only in a marginal increase in the bulk matrix crystallinity of PVDF as determined by DSC. Scanning electron micrographs of fracture surfaces from tensile tested specimens exhibited a typical brittle failure mode with low fibre loading fraction. Despite the presence of up to 5% of voids and visible resin rich regions at fracture surface, SFC containing APF-treated fibres suggest better bonding at the fibre/matrix interface which led to the much enhanced mechanical properties.     

Linear versus Network Scheduling: A Critical Path Comparison

Linear scheduling methods provide an alternative way of scheduling repetitive projects, to the commonly used network methods. Critical path identification is a major attribute for both methods; therefore, it is very important for practitioners to understand the function of the two methods in this area. The present paper compares the critical path of the recently developed Kallantzis-Lambropoulos repetitive project model against the network scheduling critical path method (CPM), aiming at delving into and pointing out the differences and similarities between them. Initially, the rules for transforming the linear project into an equivalent CPM network are proposed. Then, the rules are applied on a sample linear project. Due to the additional constraint for maintaining resource continuity that the linear method takes into account, the critical paths vary. The constraint is subsequently removed from selected activities and comparison is repeated; the critical paths then coincide. In order to validate the findings and ensure impartiality of results, a random linear project generator is developed. A group of twenty-five random linear projects and their equivalent networks is produced. Their critical paths are analyzed, compared and classified. Conclusions support that the proposed comparison could be beneficial to users of linear scheduling methods, while the random project generator can serve other related research.     

Amalthaea: An Evolving Multi-Agent Information Filtering and Discovery System for the WWW

Amalthaea is an evolving, multi-agent ecosystem for personalized filtering, discovery, and monitoring of information sites. Amalthaea's primary application domain is the World Wide Web and its main purpose is to assist its users in finding interesting information. Two different categories of agents are introduced in the system: filtering agents that model and monitor the interests of the user and discovery agents that model the information sources.A market-like ecosystem where the agents evolve, compete, and collaborate is presented: agents that are useful to the user or other agents reproduce, while low-performing agents are destroyed. Results from various experiments with different system configurations and varying ratios of user interests versus agents in the system are presented. Finally issues like fine-tuning the initial parameters of the system and establishing and maintaining equilibria in the ecosystem are discussed.     

Gallium nitride-based potentiometric anion sensor

The gallium nitride (GaN) semiconductor is used as the sensing element for the development of a potentiometric anion sensor. The anion recognition mechanism is based on the selective interaction of anions in solution with the epitaxial Ga-face polarity GaN (0001) wurtzite crystal film grown on sapphire. The native GaN crystal is used for the development of an ion blocked sensor. The potential is based on the Volta potential, generated at the semiconductor/solution interface and within the Helmholtz layer, due to specifically adsorbed anions. The selectivity of the sensor is based on the direct interaction of the anionic ligand with the outer electron-defective gallium atoms; thus, it is not dependent on the lipophilicity of the adsorbed charged species. The chemical resistivity of the GaN crystal provides sensors with excellent lifetime, signal stability, and reproducibility.     

Probabilistic integer sorting

We introduce a probabilistic sequential algorithm for stable sorting n uniformly distributed keys in an arbitrary range. The algorithm runs in linear time and sorts all but a very small fraction of the input sequences; the best previously known bound was . An EREW PRAM extension of this sequential algorithm sorts in O((n/p+lgp)lgn/lg(n/p+lgn)) time using p?n processors under the same probabilistic conditions. For a CRCW PRAM we improve upon the probabilistic bound of obtained by Rajasekaran and Sen to derive a bound. Additionally, we present experimental results for the sequential algorithm that establish the practicality of our method.     

Balancing energy efficiency and quality of aggregate data in sensor networks

In-network aggregation has been proposed as one method for reducing energy consumption in sensor networks. In this paper, we explore two ideas related to further reducing energy consumption in the context of in-network aggregation. The first is by influencing the construction of the routing trees for sensor networks with the goal of reducing the size of transmitted data. To this end, we propose a group-aware network configuration method that clusters along the same path sensor nodes that belong to the same group. The second idea involves imposing a hierarchy of output filters on the sensor network with the goal of both reducing the size of transmitted data and minimizing the number of transmitted messages. More specifically, we propose a framework to use temporal coherency tolerances in conjunction with in-network aggregation to save energy at the sensor nodes while maintaining specified quality of data. These tolerances are based on user preferences or can be dictated by the network in cases where the network cannot support the current tolerance level. Our framework, called TiNA, works on top of existing in-network aggregation schemes. We evaluate experimentally our proposed schemes in the context of existing in-network aggregation schemes. We present experimental results measuring energy consumption, response time, and quality of data for Group-By queries. Overall, our schemes provide significant energy savings with respect to communication and a negligible drop in quality of data.Received: 22 October 2003, Accepted: 16 April 2004, Published online: 12 November 2004Edited by: J. Gehrke and J. HellersteinThis work is supported in part by NSF award ANI-0123705. The first author is supported in part by the Andrew Mellon Predoctoral Fellowship. This paper expands on the material presented in two workshops [31,2].     

Can a left internal jugular catheter be used in the hemodialysis of a patient with persistent left superior vena cava?

A patient with a persistent left superior vena cava (PLSVC) was incidentally diagnosed after positioning of a dual lumen catheter for hemodialysis into the left internal jugular vein. Although PLSVC is a relatively rare condition, it is the most common congenital anomaly of thoracic venous circulation. It represents the persistence of the left horn of the embryonic sinus venosus, which normally involutes during embryogenesis to become the coronary sinus. The existence of a PLSVC can cause a significant diagnostic dilemma during catheterization of the left internal jugular vein, pertaining to the positioning of the catheter. It may also be associated with significant clinical implications such as systemic embolization, provocation of arrhythmia, and thrombosis of the vessel. The safety of such catheterization has not been adequately evaluated due to the rarity of this condition. We believe that a diagnostic workup including blood gas analysis, echocardiography, and computed tomography is necessary to confirm a right atrial drainage and a patent innominate vein as prerequisites to maintain the catheter in position.     

Palygorskite–TiO2 nanocatalysts for photocatalytic degradation of tebuconazole in water

Palygorskite–TiO₂ nanoparticles are frequently used as nanocatalysts. In the present study, two different nanocatalysts were developed based on the use of different palygorskite–TiO₂ ratios: 40–60 and 10–90. The nanocomposites were investigated for the photocatalytic degradation of the common fungicide tebuconazole (TEB), under aquatic conditions. The samples were extensively characterized by X-ray powder diffraction, attenuated total reflectance–Fourier transform infrared spectroscopy, scanning electron microscopy and N₂ specific surface area (SSA) by Brunauer–Emmett–Teller (BET) analytical techniques. The TiO₂ nanoparticles were successfully dispersed on the mineral's surfaces and the photocatalytic activity reached 88.4% for the palygorskite–TiO₂ ratio of 40:60, where the dispersion was better as proved by the total pore volume and BET parameters (0.49 cm³/g and 258 m²/g compared to 0.33 cm³/g and 220 m²/g of the 10:90 ratio). The photocatalytic efficiency of the proposed materials was significantly higher than Degussa P25 (33.2%), and that makes the palygorskite–TiO₂ nanocomposites very promising for advanced application in fungicides' degradation in aquatic environments.