Regulation of melanogenesis in B16 mouse melanoma cells by protein kinase C

Serotonergic neuronal networks are important for food intake and body weight regulation. Dexfenfluramine (dF), a serotonin releaser and reuptake inhibitor, was used to investigate changes in food intake, body weight development, energy expenditure, respiratory quotient, and substrate oxidation rates for 12 days. Rats, which had been made obese by early postnatal overfeeding, received an energy-controlled mash diet and water ad lib and were intraperitoneally injected daily with either saline, 5 or 10 mg dF/kg. Compared to controls, food intake, body weight development, and energy expenditure were decreased in a dose-dependent manner, especially during the first 6 days. Lipid oxidation was increased while oxidation of carbohydrates was decreased. Pair-feeding experiments over 2 days revealed that this was not solely a result of diminished food intake but also an additional metabolic effect of dF, different from its anorectic effect. At the end of these experiments, plasma glucose and liver glycogen were unchanged after dF, but plasma free fatty acids were significantly decreased. Insulin-sensitivity was probably improved, indicated by decreased insulin levels and increases in muscle glycogen contents and activities of muscle pyruvate kinase. Liver-glutamine and contents of valine, leucine, and isoleucine in the muscle were significantly decreased after dF-treatment, the latter indicating a diminished proteolysis. The plasma tryptophan/large neutral amino acids ratio of the dF-rats was unchanged but that of the paired-fed rats was changed, despite similar changes in food intake. It is concluded that both increased oxidation of endogenous fat and reduced food intake could mediate the body weight reducing effect of dF.     

Liquid-phase sintering of TiN-enriched T15-grade high-speed steels and their mechanical properties

The present investigation is an attempt to develop composites based on high-speed steel through liquid-phase sintering route using a powder metallurgical technique. Water-atomised annealed T15-grade HSS powder, lubricant and various mass percents of TiN (0–8%) were blended and axially compacted into green pellets at 850 MPa at room temperature. During sintering studies carried out in vacuum (10^?2 torr), optimum temperature for full densification was determined for each composition. Only full dense sintered samples (density ≥98% theoretical) were selected for further heat treatment and the evaluation of mechanical properties. Mechanical properties like hardness, transverse rupture strength and hot compressive yield strength were evaluated. Both qualitative and quantitative metallographic studies were carried out and chemical analysis of various phases in sintered as well as heat-treated composites were determined using SEM-EDX. The results confirm that fully dense composites containing up to 2% TiN exhibit equivalent mechanical properties, although some differences in service behaviour e.g. wear resistance are to be expected.     

System-level reliability assessment of mixed-signal convergent microsystems

The next-generation convergent microsystems, based on system-on-package (SOP) technology, require up-front system-level design-for-reliability approaches and appropriate reliability assessment methodologies to guarantee the reliability of digital, optical, and radio frequency (RF) functions, as well as their interfaces. Systems approach to reliability requires the development of: i) physics-based reliability models for various failure mechanisms associated with digital, optical, and RF Functions, and their interfaces in the system; ii) design optimization models for the selection of suitable materials and processing conditions for reliability, as well as functionality; and iii) system-level reliability models understanding the component and functional interaction. This paper presents the reliability assessment of digital, optical, and RF functions in SOP-based microsystems. Upfront physics-based design-for-reliability models for various functional failure mechanisms are presented to evaluate various design options and material selection even before the prototypes are made. Advanced modeling methodologies and algorithms to accommodate material length scale effects due to enhanced system integration and miniaturization are presented. System-level mixed-signal reliability is discussed thorough system-level reliability metrics relating component-level failure mechanisms to system-level signal integrity, as well as statistical aspects.     

Colloid cyst xanthogranuloma of the third ventricle--a case report

Diagnosis and treatment of malignant pericardial effusion are difficult in clinical practice. This paper reports the feasibility and reliability of percutanous trans-catheter intervention for the diagnosis and treatment of malignant pericardial effusion. Under echocardiagraphic guidence, pericardial puncture was performed and a heamostasis sheath was placed in situ by Seldinger technique. Through the sheath multiple biopsies of the pericardium were taken for pathological examination. A pigtail catheter was inserted to drain off the effusion. According to pathological report suitable anti-cancer drugs were instilled into the pericardial cavity through indwelling catheter for 3-5 days. The catheter was withdrawn when fluid did not re-accumulate. Diagnosis was made in over 96.0% of the cases. Upon follow-up for 3-6 months, complete remission was seen in 96.0% of the treated patients. No significant complication was found in all patients. Percutaneous trans-catheter intervention is a useful approach for the diagnosis and treatment of malignant pericardial effusion.     

Sorption kinetic studies of water vapour on activated carbon beds

Experimental measurements of the adsorption kinetics of water in activated carbon beds at different values of relative humidity have been made. The development of a simple theoretical model based on inter- and intra-particle mass transfer taking into account the thermal effects of sorption of water in activated carbon beds is described. The comparison of the model results with the experimental data is also presented. It is concluded that a single value of the estimated mass transfer coefficient can be used to reasonably predict the adsorption behaviour of water in activated carbon beds.     

Analysis of a thrust bearing with a viscoelastic lubricant

The characteristics of a thrust bearing with a viscoelastic lubricant have been analysed. The elasticity of the lubricant, the volume rate of flow of lubricant and the ratio of the inner and outer radii of the bearing are characterized by the parameters α, β and σ. The effects of these parameters on the pressure distribution and the load-bearing capacity have been studied.     

Recent Developments in Multiphase Metallic Materials

This paper briefly reviews some recent developments in multiphase metallic materials with a specific emphasis on how fundamental metallurgical understanding has guided the development of materials with tailored micro-structures and useful mechanical properties.     

Type-of-service routing in datagram delivery systems

The Internet is expected to support various services, including best-effort services and guaranteed services. For best-effort services, we propose a new approach to achieving type-of-service (TOS) classes with adaptive next-hop routing. We consider two TOS classes, namely, delay-sensitive and throughput-sensitive. As in routing protocols such as OSPF and integrated IS-IS, each node has a different next-hop for each destination and TOS class. Traditionally, a node has a single FCFS queue for each outgoing link, and the next-hops are computed using link measurements. In our approach, we attempt to isolate the two traffic classes by using for each outgoing link a separate FCFS queue for each TOS class; the link is shared cyclicly between its TOS queues. The next-hops for the delay-sensitive traffic adapts to link delays of that traffic. The next-hops for the throughput-sensitive traffic adapts to overall link utilizations. We compare our approach with the traditional approach using discrete-event simulation and Lyapunov analysis (for stability of routes). Our approach offers lower end-to-end delay to the delay-sensitive traffic. A related property is that the routes for the delay-sensitive traffic are more stable, i.e., less oscillations. An unexpected property is that the overall end-to-end delay is lower, because the throughput-sensitive traffic moves away to under-utilized routes