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Severe hypertriglyceridemia is an urgent presentation that requires acute treatment. We present a rare case that could not be controlled by medical management and required plasmapheresis.

The idea of sharing resources is a world tendency that is spreading quickly because people's behavior is continually changing due to a lot of variables, such as easy access to technology. Some examples that can illustrate this transformation are: Airbnb, Couchsurfing and Uber. Taking a look from a perspective that comprises both economy and environmental issues, vehicle sharing is a concept that brings a lot of easiness and benefits for those who used as a sustainable means of locomotion. This paper aims to contribute with a sustainable vision already adopted by Itaipu Binacional, the most important hydroelectric power plant in Brazil. To achieve this, a carsharing platform (MoVE) was developed to include electric vehicles to be used by Itaipu employees. Trying to achieve high scalability, MoVE platform offers an API that allows communication with any hardware that is capable of collecting vehicle data.

Atomic force acoustic microscopy is a near-field technique which combines the ability of ultrasonics to image elastic properties with the high lateral resolution of scanning probe microscopes. We present a technique to measure the contact stiffness and the Young's modulus of sample surfaces quantitatively, with a resolution of approximately 20 nm, exploiting the contact resonance frequencies of standard cantilevers used in atomic force microscopy. The Young's modulus of nanocrystalline ferrite films has been measured as a function of oxidation temperature. Furthermore, images showing the domain structure of piezoelectric lead zirconate titanate ceramics have been taken.

The velocities in the mixing region of a cross flow jet injected into a freestream were studied in detail with a laser velocimeter. Three jet to freestream momentum ratios were used (3.1, 8.1, 16.2). By purposely seeding the jet and freestream separately (as well as both simultaneously), “marking” the fluid was feasible. Thus, determining the velocities that emanated from the different streams was possible. By methodically analyzing the three sets of dependent data, the size and location of the mixing region was determined. The mixing regions for the three momentum ratios were found to be of different sizes and at different locations. By proper scaling, however, the regions for the three momentum ratios were found to collapse to one scaled region. Because of the intermittent behavior of the mixing, conventional turbulence models for such mixing may not be applicable; however, detailed velocities and turbulence quantities are included for “benchmarking” predictions.

A measurement technique to determine the surface heat transfer distribution in complex turbulent flows is described. For this purpose, a constant wall heat flux test surface has been designed. To measure the surface temperature of the test plate, an infrared camera was used. The instrumentation allows the determination of the heat transfer with high accuracy and detailed spatial resolution. In examining combustor-type separated flow, the capabilities of the technique are demonstrated and its accuracy is verified by appropriate conventional techniques.

The precise etiology of ocular vascular occlusions is not known in all details. The pathogenesis may be associated with abnormalities of blood rheology and coagulation. Frequently, it is associated with an underlying systemic disease (Table 1). Despite many years of investigation and research, some principles of the pathophysiology and therapy of this disease entity remain unclear.

Ceramic materials with heterogeneous phase content and internal boundaries are unique in their electromechanical properties. Due to the interaction between those properties, these so-called multifunctional materials are suited for the realization of parts that have to yield complex functions in a system such as sensors and actuators. The knowledge of the materials microstructure and the elastic constants is essential for materials optimization and quality assessment. In this article, nondestructive techniques are presented to evaluate the microstructure and the elastic constants of a number of lead titanate zirconate (PZT) piezoceramics. Ultrasonic pulse-echo techniques were used to determine the elastic constants of different materials. When the piezoelectric material is poled, i.e., when the ferroelectric domains have a preferred orientation, we observe an increased sound velocity when the wave polarization is parallel to the poling direction. This elastic stiffening effect is being described theoretically. Finally, the Atomic Force Microscope (AFM) has been employed to image the ferroelectric domains of the piezoceramics. The microfabricated conductive tip of an AFM was used as a single electrode to excite vibrations of individual ferroelectric domains. Depending on their orientation, the recorded vibration amplitude varies between the domains and hence, forms a contrast.

Conventional friction force microscopy (FFM) is widely used for tribological studies of engineering surfaces. It is, however, difficult to separate friction forces resulting from interactions dependent upon interfacial material properties from surface topography-induced lateral forces. We have developed and employed a technique to operate acoustic friction force microscopy (AFFM) by oscillating the sample laterally at megahertz frequencies. The in-plane vibrations perpendicular to the longitudinal axis of the cantilever are generated because of lateral forces between the probe tip and the sample. Torsional cantilever vibrations were detected at frequencies of up to 2 MHz. A mean cantilever lift-off was observed that can be explained by elastohydrodynamic lubrication. The high-frequency torsional vibration amplitude provides information about the lateral forces that can be used to calculate the friction and viscosity of thin surface films. The AFFM images of metal-particle magnetic tapes were produced, revealing a resolution apparently better than FFM images. Unlike FFM images, AFFM images are independent of the scanning direction, indicating that AFFM images are less sensitive to topography-induced lateral forces. Also, AFFM, allows friction measurements at relative velocities of the order of 1 mm s −1 which is much larger than that obtained in conventional FFM (several μm s−1). Copyright © 1999 John Wiley & Sons, Ltd.

Detailed measurements of local heat transfer coefficients are presented for air injection through a row of holes into a crossflow. Pitch-to-diameter ratios of 2,4, and 6 are realized and the momentum flux ratio is varied in the range from 0.25 to 4.0. The injection angle of the jets is fixed at 90°. The experimental technique developed uses an Infrared Camera to measure the temperature distribution on the constant heat flux test surface. This measurement technique allows detailed spatial resolution of the heat transfer and gives information about the three-dimensional mixing process of the jets with the mainstream. The experimental results indicate a large influence of the hole spacing to diameter ratio, (s/d), on the heat transfer coefficient. With s/d = 2.0, the spanwise heat transfer coefficients in the vicinity of the injection holes are noticed to be highly uniform. For momentum flux ratios, J, greater than 1, two regions of high heat transfer coefficient exist. The first region occurs in the vicinity of the injection holes. The second region observed some distance downstream is due to the reattachment of the jets to the surface.Copyright © 1991 by ASME

It is shown that microdischarges can be caused to occur between vacuum insulated electrodes by exposing the electrode surfaces to oil contamination or to the condensation of electronegative gases (H2O, CO2). The presence of the condensed H2O layers at low electrode temperatures lowers the microdischarge onset by a factor of 3 and the implication of this for microdischarge theory and vacuum cable development are discussed. A theory is presented which enables the onset of breakdown in the gas released by the microdischarge to be calculated.