Rapid prototyping: Applications in academic institutions and industry

In today's competitive world, the manufacturers have to get a new and improved product to the market as fast as possible to be able to compete in the global market. The major obstacle for this task had been a long product development cycle, i.e., design, prototype manufacture and testing. The introduction of rapid prototyping (RP) in the early stages of product development has greatly reduced the development time frame and cost involved in prototype manufacturing. Furthermore, RP applications are growing very fast in such a way that it is now possible to produce parts not as prototypes, but as final parts to be used in several engineering applications. Thus, RP is now acting as a bridge to help designers, manufacturing engineers, marketing and sales personnel to provide goods timely to the customer. This paper discusses practices, current developments and future trends of RP. This paper also discusses the use and role of RP in academic institutions.     

IR studies of CO and NO adsorbed on well characterized oxide single microcrystals

A systematic investigation of the surface morphology and of the vibrational properties of CO and NO adsorbed on simple oxides microcrystals (like MgO, NiO, NiO-MgO, CoO-MgO, ZnO, ZnO-CoO, -Cr₂O₃, -Al₂O₃, MgAl₂O₄ and other spinels, TiO₂, ZrO₂ and other oxides of a similar structure) with regular crystalline habit and exposing thermodynamically stable and neutral faces, is presented with the aim to elucidate the spectroscopic manifestations of CO and NO adsorbed on well defined crystallographic positions.

In particular the structure of CO and NO adsorbed on the cationic sites of extended faces of these model solids is presented and discussed with the aim of elucidating the nature of the Me^x+··· CO/NO bond (Me^x+ = non transition metal ion or transition metal ion). When non transition metal ions are involved, the molecule-cation interaction is predominantly electrostatic. This leads to an increase of the CO stretching frequency, which is roughly proportional to the polarizing field. On the contrary, when transition metal ions are involved, beside the predominant electrostatic interactions, a small contribution to the bond stability comes also from d-π overlap forces, which, although not very important from the energetic point of view, greatly influence the static and dynamic dipoles localized on the adsorbed molecules. Consequently, the strength of the dipole-dipole interactions occurring in the ordered adlayers of CO and NO adsorbed on transition and non transition metal oxide surfaces are resulted remarkably different.

On these well defined surfaces, the effects influencing the half-width (FWHM) of the CO and NO stretching peaks have also been considered. It has been calculated that the FWHM is a very sensitive parameter of the surface perfection. In a few cases (ZnO, -Cr₂O₃, etc.) FWHM values comprised in the 1.5–3.7 range have been obtained, which are indicative of a single-crystal quality of the exposed faces. These spectroscopic results were compared with those obtained with quantum calculations.

Finally the activity towards CO and NO of perfect, low index faces and of more defective situations (like those associated with edges, steps and corners) are compared, in order to have a better insight on the role of surface defectivity in catalytic reactions.     

Phenolic Profile of Peanut By-products: Antioxidant Potential and Inhibition of Alpha-Glucosidase and Lipase Activities

Free, esterified, etherified and insoluble‐bound phenolics from three samples, namely meal from whole peanuts (MWP), meal from dry‐blanched peanuts (MDBP) and peanut skin (PS) were evaluated for their total phenolic content (TPC), and phenolic profile using HPLC–DAD–ESI–MSⁿ. The TPC was in the order of PS > MWP > MDBP. Among 37 compounds identified 10 were reported for peanuts for the first time. Proanthocyanidins were detected in peanut skin and MWP, but not in MDBP. The presence of peanut skin in MWP rendered up to 9.8‐fold higher scavenging activity towards the DPPH radical as compared with MDBP. Phenolics from all samples and fractions showed inhibition of alpha‐glucosidase and lipase activities, which are key enzymes involved in the absorption of glucose and triacylglycerols, respectively. Therefore, their antioxidant properties as well as their potential role in the management of diabetes and obesity makes them worthy of further consideration as functional food ingredients.     

Hardware-In-the-Loop Simulation with X-Plane of Attitude Control of a SUAV Exploring Atmospheric Conditions

The attitude control law for fixed-wing small unmanned aircraft proposed in this paper is constructed based on two phases of a flight: stable flight and maneuvering flight. In the maneuvering flight, the aircraft deflects the main control surfaces (ailerons and elevator), whereas on the stable flight only the trim tabs are deflected. The switch between the two flights is done when the aircraft enters a zone in which the difference between the aircraft’s attitude and the reference value that the airplane needs to reach is greater than a predetermined value. The control laws are implemented on an on-board computer and are validated though Hardware-In-the-Loop (HIL) simulations, between the hardware and the flight simulator X-Plane, which simulates the unmanned aircraft dynamics, sensors, and actuators. The paper proves that this implementation can reduce the rise time and the overshoot, compared with traditional PID implementations. In order to analyze the behavior of the SUAV in these situations, it was performed simulations with Wind Gust and levels of Turbulence, using the X-Plane features.     

An IMU/UWB/Vision-based Extended Kalman Filter for Mini-UAV Localization in Indoor Environment using 802.15.4a Wireless Sensor Network

Indoor localization of mobile agents using wireless technologies is becoming very important in military and civil applications. This paper introduces an approach for the indoor localization of a mini UAV based on Ultra-WideBand technology, low cost IMU and vision based sensors. In this work an Extended Kalman Filter (EKF) is introduced as a possible technique to improve the localization. The proposed approach allows to use a low-cost Inertial Measurement Unit (IMU) in the prediction step and the integration of vision-odometry for the detection of markers nearness the touchdown area. The ranging measurements allow to reduce the errors of inertial sensors due to the limited performance of accelerometers and gyros. The obtained results show that an accuracy of 10 cm can be achieved.     

Ultrastructure of submandibular salivary glands of mouse: TEM and HRSEM observations

The fine structure of submandibular glands of mouse were analyzed using light microscopy (LM), high resolution scanning electron microscopy (HRSEM), and transmission electron microscopy (TEM) methods. For LM, the specimens were embedded in Spurr resin, stained by toluidin blue solutions. For TEM, the tissues of submandibular salivary glands were fixed with modified Karnovsky solution and postfixed with osmium tetroxide. For HRSEM, the tissues were fixed with 2% osmium tetroxide solution in 1/15M sodium phosphate buffer (pH 7.4). The samples were immersed successively in dymethylsulphoxide and freeze cracked. The maceration was made in diluted osmium tetroxide for 24-48 h. The samples were examined by high resolution scanning electron microscopy. The intracellular components of acinar and ductal cells revealed clearly the Golgi apparatus, rough endoplasmic reticulum, secretory granules, and mitochondria. The end bulbs of Golgi lamellae and flattened cisterns of rough endoplasmic reticulum showed the luminal surface. A few mitochondria were identified intermingling between the rough endoplasmic reticulum and the mitochondriales cristae in three-dimensional HRSEM images. Secretory granules were numerous and presented different sizes. Small granules of ribosomes were attached on cistern surface, measuring 20-25 nm in diameter. Numerous arranged microvilli were found on the luminal surface of secretory canaliculus. The contact surfaces of acinar cells revealed complicated interdigitations by cytoplasmic processes. The mitochondria of duct cells were disposed vertically and surrounded by basal infoldings of plasma membranes. Basement membrane showed a spongy-like structure having an irregular surface with various strands and meshes of fine collagen fibrils.     

Ultrastructural features of the myotendinous junction of the sternomastoid muscle in Wistar rats: From newborn to aging

The myotendinous junction (MTJ) is a major area for transmitting force from the skeletal muscle system and acts in joint position and stabilization. This study aimed to use transmission electron microscopy to describe the ultrastructural features of the MTJ of the sternomastoid muscle in Wistar rats from newborn to formation during adulthood and possible changes with aging. Ultrastructural features of the MTJ from the newborn group revealed pattern during development with interactions between muscle cells and extracellular matrix elements with thin folds in the sarcolemma and high cellular activity evidenced through numerous oval mitochondria groupings. The adult group had classical morphological features of the MTJ, with folds in the sarcolemma forming long projections called “finger‐like processes” and sarcoplasmic invaginations. Sarcomeres were aligned in series, showing mitochondria near the Z line in groupings between collagen fiber bundles. The old group had altered “finger‐like processes,” thickened in both levels of sarcoplasmic invaginations and in central connections with the lateral junctions. We conclude that the MTJ undergoes intense activity from newborn to its formation during adulthood. With increasing age, changes to the MTJ were observed in the shapes of the invaginations and “finger‐like processes” due to hypoactivity, potentially compromising force transmission and joint stability. Microsc. Res. Tech. 75:1292–1296, 2012. © 2012 Wiley Periodicals, Inc.     

Restoration of drastically eroded land using coal fly ash and poultry biosolid

A 3-year field study was conducted at a 12 ha soil-borrow area adjacent to the Columbia Metropolitan Airport, South Carolina to investigate the restorative effects of co-application of coal fly ash (FA) and a poultry biosolid (PB). FA was applied at 0, 22, 280, 560 and 1120 Mg (tonne) ha(-1), and PB at 5 and 10 Mg ha(-1). The area was seeded with erosion-control species Atlantic Coastal panic grass (Panicum amarum var amarum L.), sericea (Lespedeza cuneata var. appalow [Dumont] G. Don.) and weeping love grass (Eragrostis curvula Wolf.). Plant biomass and elemental composition were analyzed in sequential harvests. Soil and groundwater quality characteristics including pH, EC and elemental composition were also monitored throughout the study. In addition, the effect of amendments on the water holding capacity and bulk density of the soil was investigated. Amendment addition significantly increased plant biomass production by a maximum of 26% using 1120 Mg ha(-1) FA and 10 Mg ha(-1) PB. Application of the highest rate of FA significantly increased the plant tissue concentrations of Mn, As, Se and B. Soil pH was initially increased from 4.6 to 6.1 by amendments. Soil salinity was increased in the initial year only. Amended soils had higher concentrations of Ca, Mg, P and K, higher organic matter content and water holding capacity than unamended soil. Concentrations of plant-essential trace elements (B, Cu and Zn) that were marginally deficient in the unamended eroded soil increased to within typical soil concentrations following amendment with FA and PB. Groundwater quality was unaffected throughout the study. The co-application of FA and PB successfully promoted the revegetation of the eroded borrow area with no apparent adverse environmental side effects.     

Bovine milk powder adulteration with vegetable oils or fats revealed by MALDI-QTOF MS

Matrix-assisted laser desorption/ionisation-quadrupole time of flight mass spectrometry (MALDI-QTOF MS) allowed detection of bovine milk powder adulteration with vegetable oils or fats with high speed and reliability, requiring little sample preparation (n-hexane extraction) and no prior separation procedures. This technique was also able to identify the adulterated employed in this fraud. Hydrogenated soybean oil addition in bovine milk powder sample generate a similar TAG profile to that observed on adulterated milk samples apprehended by the Brazilian Federal Police. In this sense, a robust method for high throughput forensic screening of milk powder adulteration by exogenous oils and fats is showed.     

Repercussions on sarcomeres of the myotendinous junction and the myofibrillar type adaptations in response to different trainings on vertical ladder

The myofibrillary types establish to the skeletal muscle functional and adaptive properties that influence the sarcomeric arrangement during muscle contraction and may have repercussions on an important related force transmission region of the locomotor apparatus, the myotendinous junction (MTJ). This study aimed to describe changes in myofibrillary type and sarcomeric lengths in the belly muscle and MTJ of the soleus and plantaris muscles associated with training protocols in vertical ladder. Thirty adults male Wistar rats were divided into three groups (n = 10): Control (CTR), No‐load Training (NLT), and Load Training (LT). Morphoquantitative analysis of different fibers types and sarcomere lengths were performed in distinct regions of plantaris and soleus muscles. In the plantaris muscle with both trainings, there was an increase in the cross‐sectional area (CSA) in Type I and II fibers (p < .0001) while sarcomeric lengths revealed greater lengths in the proximal and distal sarcomeres of NLT, although in the LT we found greater lengths in the belly and MTJ sarcomeres. The soleus muscle showed an increase in CSA muscle fiber only in the NLT (p < .0001) and revealed alterations in belly and MTJ sarcomere lengths with training. We concluded that plantaris muscle has an adaptive effect directly associated with training load, with hypertrophy in both trainings and sarcomere length inverse from belly and MTJ, in LT associated with increased force generation and transmission at the MTJ, although soleus muscle has a lower adaptive response to training stimuli with variation in the belly and distal sarcomere of the MTJ.