An Evaluation of Non-Stochastic Lattice Structures Fabricated Via Electron Beam Melting

Metal foam structures have many applications and can be used as structural supports, heat exchangers, shock absorbers, and implant materials. Stochastic metal foams having different cell sizes and densities have been commercially available for a number of years. This paper addresses a different type of foams which are known as non-stochastic foams, or lattice structures. These foams have a well defined repeating unit cell structure rather than the random cell structure in commercially available stochastic foams. The paper reports on preliminary research on the fabrication of non-stochastic Ti-6Al-4V alloy foams using the Electron Beam Melting process. Behavior of the structures in compression, bending, and low cycle repeating load tests are discussed, and recommendations about cell geometry and processing conditions are made.Mechanical Engineerin

Processing of citrus peel for the extraction of flavonoids for biotechnological applications

Flavonoids are extra nutritional constituents that naturally occur in small quantities in plants. They are a family of polyphenolic compounds that are widespread in nature and are consumed as part of the human diet in significant amounts. The diversity in their structure and bioactivity of flavonoids make these compounds an interesting candidate for biotechnology based research. Extraction of flavonoids from citrus employing the use of various techniques such as chemical and physical methods is attempted in this write up. The biotechnological potential of flavonoids is not currently exploited to its maximum since extraction procedures are in developing phase. The current knowledge on the sources of citrus flavonoids and their potential activities in alleviating human health is also discussed

Performance and Stability of an Agile Tail-less MAV with Flexible Articulated Wings

This paper considers the problems of (a) modelling the ight mechanics of a tail-less MAV equipped with exible articulated wings, and (b) the analysis of its turning performance. The wings are assumed to have two degrees of freedom - heave and twist. They are assumed to be actuated from the root, which is the abstraction of an experimental control mechanism being developed by the authors. The dihedral and twist angles at the wing root are controlled. A novel actuator concept of axial tension to control wing stiffness has been explored in this paper. It is shown that axial tension in the wing has a significant effect on the turning performance of the aircraft, although the effect is not uniformly beneficial in nature. The effect of exibility on the steady state turning performance of the aircraft has been demonstrated by comparing it with that of a rigid aircraft, and with that of a similar aircraft possessing a wing with different elastic properties

The correlation between full biophysical profile and rapid biophysical profile in antepartum fetal surveillance

Background: The aim of this study was to assess the efficiency of rapid biophysical profile in antepartum fetal surveillance and ability to predict adverse perinatal outcome and to compare it with the gold standard full biophysical profile. The objective was to determine the correlation between the rapid biophysical profile (RBP) and the full biophysical profile (FBP) and to compare the individual scores with pregnancy outcomes.Methods: A prospective study was performed in 153 singleton pregnancies with no fetal anomalies between 34-42 weeks of gestation. All participants received both the standard (FBP) and the new RBP. Abnormal fetal test was defined as having a score of ≤ 6 for FBP or ≤ 2 for RBP. The main outcome measured was Spearman’s correlation coefficient (rs) between both examinations and also between each examination and pregnancy outcomes measured in terms of Apgar scores and NICU (Neonatal Intensive Care Unit) admissionsResults: The data showed a positive correlation between the two tests (rs = 0.62; p < 0.0001). Out of the individual biophysical variables, only NST (Non Stress Test) had a positive correlation with RBP. The sensitivity, specificity, positive predictive value and negative predictive value of RBP in predicting adverse outcomes was found to be 71.4%, 87.1%, 35.7%. 96.8% respectively.Conclusions: The statistically significant positive correlation between RBP and FBP has been revealed. Due to its simplicity, rapidity, and no need for experienced interpreter, the RBP may be alternatively used as a primary screening antepartum fetal test in the overcrowded obstetric center