Enhanced‐image‐quality raster‐scanning chipset using feedback‐control actuation

Abstract— A new raster‐scanning chipset which provides enhanced projection performance is presented. The design is novel in that it combines electrostatic and electromagnetic actuation methods, along with a unique feedback‐control scheme to produce SVGA and WVGA projected images. A micromirror, the actuators, and drive electronics are integrated into a small, power‐efficient system, a scanning chipset, to increase its reliability and manufacturability.     

Effects of Nonhomogenity of Permeability on Tailings Dams

This paper has the objective of showing the influence of the permeability gradient during the construction of tailings dams, built by the upstream method, using the hydraulic fill technique. During the hydraulic disposition, two mechanisms affect the tailings permeability: the hydraulic segregation and the consolidation due the staged construction procedure. These mechanisms influence considerably the permeability distribution along the fill and, consequently, the behaviour of the dam. Results show that the pore pressure immediately after deposition may reach quite high values (532 kPa), but dissipates in a short period of time (1 to 10 days). Then, this effect should be taken into account in a short-term stability analysis of tailings dams. On the other hand, after pore pressure dissipation, there is a gain in the shear strength (13 %), which should also be considered, but in a long-term stability analysis of tailings dams.     

Photophysical study of a conjugated-non-conjugated PPV-type electroluminescent copolymer

This paper reports the photo- and electroluminescence studies of emitting species of one of the first reported blue emitters, the conjugated-non-conjugated multi-block copolymer, poly[1,8-octanedioxy-2,6-dimethoxy-1,4-phenylene-1,2-ethenylene-1,4-phenylene-1,2-ethenylene-3,5-dimethoxy-1,4-phenylene]. Because the conjugation length of the emissive center is very well defined (two and half phenylene-vinylene units) the differences found between the fluorescence profile of the fluorophore in solution, at several concentrations and that in the solid state allowed us to conclude that in solid the emission comes from associated forms, such as ground-state dimers and/or excimers. Time-resolved fluorescence in a nanosecond time scale recorded at ?_em=24,096 cm⁻¹ showed a monoexponential decay of 1.5 ns, which is compatible with rigid forms of stilbene derivatives.     

On the rate of evaporation of water into a stream of dry air, humidified air and superheated steam, and the inversion temperature

The concept of inversion temperature was developed in order to assess the effectiveness of superheated steam as a drying agent when compared with dry or humid air above a given temperature. The inversion temperature can be defined in different ways, for different physical situations, thus leading to strong discrepancies between its reported numerical values. A clear understanding of such definitions and its consequences over the inversion temperature values is of major importance, as well as the way to estimate the inversion temperature of interest for a given practical evaporation process. Analytical expressions are proposed for some possible definitions of the inversion temperature. Special emphasis is devoted to the physical reasoning on the existence of the inversion temperature and how its value is affected by other variables such as humidity level, mass flow rate and geometry of the evaporative system.     

The use of X-ray diffraction, microscopy, and magnetic measurements for analysing microstructural features of a duplex stainless steel

X-ray diffraction, light optical microscopy, and magnetization saturation measurements were employed to analyse the microstructural features of a UNS S31803 duplex stainless steel modified by high-temperature treatments. The samples were heated to 1300 °C and cooled by different ways to produce five different microstructures. Solution treatments at 1000 °C were also employed to produce another five conditions. Three methods were employed to determine the austenite/ferrite proportions. X-ray diffraction gave higher austenite values than the other methods, due to the influence of texture, but can be successfully used to determine the microstrain level in each phase. Magnetic saturation measurement is a very simple and precise method for quantification of austenite and ferrite volume fractions in samples that were fast-cooled and slow-cooled. Light microscopy can give a fast and precise measurement of the phase proportions and reveals important features related to the morphology of the phases, but in the samples where the austenite content is low, quantification becomes difficult and imprecise.     

The ParTriCluster Algorithm for Gene Expression Analysis

Analyzing gene expression patterns is becoming a highly relevant task in the Bioinformatics area. This analysis makes it possible to determine the behavior patterns of genes under various conditions, a fundamental information for treating diseases, among other applications. A recent advance in this area is the Tricluster algorithm, which is the first algorithm capable of determining 3D clusters (genes × samples × timestamps), that is, groups of genes that behave similarly across samples and timestamps. However, even though biological experiments collect an increasing amount of data to be analyzed and correlated, the triclustering problem remains a bottleneck due to its NP-Completeness, so its parallelization seems to be an essential step towards obtaining feasible solutions. In this work we propose and evaluate the implementation of a parallel version of the Tricluster algorithm using the filter-labeled-stream paradigm supported by the Anthill parallel programming environment. The results show that our parallelization scales well with the data size, being able to handle severe load imbalances that are inherent to the problem. Further more, the parallelization strategy is applicable to any depth-first searches.     

Brachial plexus injury during cardiac catheterisation in children. Report of two cases

The arm is particularly vulnerable to neurological injury, due to the intimate anatomical relationship between the brachial plexus and the traction zones. Severe injuries of the brachial plexus can be caused by compression, traction or laceration. Fortunately, many deficits are superficial and permanent neurovascular deficits are rare. Nevertheless, it is important to identify the probable cause of the injury since the prognosis for recovery directly depends on the underlying nature of the neurological deficit. Two anaesthetised children who suffered brachial plexus injury during cardiac catheterisation are reported. The first, with Ebstein's anomaly and significant pulmonary valve stenosis, presented, after the procedure, with a right arm motor deficit with proximal predominance. The second patient, with tetralogy of Fallot and pulmonary atresia, presented difficulty in left arm abduction and external rotation on awakening. The risk factors for brachial plexus lesions during anaesthesia are discussed. These include improper positioning, anaesthetic agents, extreme variations of body mass index and anatomical anomalies. Prevention, evolution and treatment of the brachial plexus injury are also considered. With proper care by the cardio-radiologist and anaesthesiologist the frequency of this injury can be reduced.     

Lumped-differential analysis of concurrent flow double-pipe heat exchanger

A mixed lumped-differential formulation for double-pipe heat exchangers is presented that radially lumps the temperature distribution in the outer channel, providing a differential problem for the inner channel that involves a more general type of boundary condition for the wall temperature. The generalized integral transform technique is extended to allow for the analytical solution of this class of problems. Applicability limits for the simplified model are then established in terms of related parameters, based on numerical results obtained for bulk temperatures and Nusselt numbers, as compared to more involved approaches for the complete differential model.     

Arterial branches to the Palmaris Longus muscle

The use of the long palmar muscle in surgeries of muscular transposition and transplantation in orthopedic and plastic surgeries has encouraged the investigation of arterial branches for the long palmar muscle. This study was carried out in 58 upper limbs of child cadavers aged up to one year. It was observed that the muscle was not present in 31.04% of the forearms. It more frequently presents one to two arterial branches which arise mainly, from the ulnar artery (85.71%) and less frequently from brachial artery (22.86%). The arterial branches penetrate the muscle through the posterior face, 62.71% being at the proximal third and 33.90% at the medium third. The most frequent models of the branch disposition were from one to two branches of the ulnar artery which penetrate the proximal thirds (28.57%) and two branches of the ulnar artery, the median and proximal thirds, respectively (17.14%).