Experimental and analytical studies of a model helicopter rotor in hover

A benchmark test to aid the development of various rotor performance codes was conducted. Simultaneous blade pressure measurements and tip vortex surveys were made for a wide range of tip Mach numbers including the transonic flow regime. The measured tip vortex strength and geometry permit effective blade loading predictions when used as input to a prescribed wake lifting surface code. It is also shown that with proper inflow and boundary layer modeling, the supercritical flow regime can be accurately predicted

Finite difference modeling of rotor flows including wake effects

Rotary wing finite difference methods are investigated. The main concern is the specification of boundary conditions to properly account for the effect of the wake on the blade. Examples are given of an approach where wake effects are introduced by specifying an equivalent angle of attack. An alternate approach is also given where discrete vortices are introduced into the finite difference grid. The resulting computations of hovering and high advance ratio cases compare well with experiment. Some consideration is also given to the modeling of low to moderate advance ratio flows

Role of “mate tea” extracts modulating DNA methylation: in vitro studies for future significances for human health

It is known that a healthy and balanced diet is essential for maintaining a state of good health of the individual, and that the onset of many diseases is related to inadequate nutrition. Many small molecules contained in foods (Food Small Molecules, SFMs) have the ability to influence the functioning of many cellular metabolic pathways. The term nutrigenomics, in fact, refers to an emerging branch of genetics and biochemistry which has the aim of identifying how the nutrients can determine the innate risk of developing diseases (diabetes, obesity, cardiovascular disease and some cancers). In addition, with the help of epigenetics, it is possible to further understand how the SFMs act on DNA, influencing gene expression and, perhaps its transmission to the future generations. Today it is known, in fact, that the gene expression depends not only from the primary sequence of its promoter, but also from the local chromatin status: the methylation of cytosine in a DNA is one among the most studied mechanisms of chromatin remodeling and, thus, of regulation of gene expression. Recently was reported that plant derived SFMs, can act as epigenetic modulators. For example, epigallocatechin gallate and indicaxanthin, flavonoids present in green tea and Opuntia Ficus Indica, respectively, are, for these reasons, in process to be labelled as anticancer agents. It is known that drinks made from "Mate tea", highly consumed in Argentina, as well as in other South American countries, may provide important health effects. This project is aimed to investigate whether "Mate tea" extracts and components, given to cultured cell lines may act as a modulator of DNA methylation. If this epigenetic action can be proved, it could promote the consumption of Mate tea – based beverages as precise nutritional strategy to prevent disease, as well as identify the component(s) that could have pharmacological property

An experimental investigation of the parallel blade-vortex interaction

A scheme for investigating the parallel blade vortex interaction (BVI) has been designed and tested. The scheme involves setting a vortex generator upstream of a nonlifting rotor so that the vortex interacts with the blade at the forward azimuth. The method has revealed two propagation mechanisms: a type C shock propagation from the leading edge induced by the vortex at high tip speeds, and a rapid but continuous pressure pulse associated with the proximity of the vortex to the leading edge. The latter is thought to be the more important source. The effects of Mach number and vortex proximity are discussed

The structure of trailing vortices generated by model rotor blades

Hot-wire anemometry to analyze the structure and geometry of rotary wing trailing vortices is studied. Tests cover a range of aspect ratios and blade twist. For all configurations, measured vortex strength correlates well with maximum blade-bound circulation. Measurements of wake geometry are in agreement with classical data for high-aspect ratios. The detailed vortex structure is similar to that found for fixed wings and consists of four well defined regions--a viscous core, a turbulent mixing region, a merging region, and an inviscid outer region. A single set of empirical formulas for the entire set of test data is described

ANTERIOR OPEN BITE TREATED WITH E F APPLIANCE: A CASE REPORT

Aim. Current trends in pediatric orthodontics aim to identify incorrect development of occlusion and medium/lower facial third as early as possible. Functional appliances are a popular type of device used for treating malocclusion in patients who are growing. Among the functional orthodontic devices intended for this purpose, \u201cEducation Functional\u201d is highlighted. It was developed by Dr. Daniel Rollet. In fact, in the occlusal alterations, early preventive treatment with elastodontic devices resulted in avoiding dysfunctional forces from acting on the skeletal pattern, thus reaching a balance between bone basis and muscular components. This report describes a clinical case of a patient (9-year-old female) with anterior open bite associated to oral dysfunction, treated, in the mixed dentition, with EF-line appliance. Our purpose is to evaluate the effectiveness of this device for the correction of the dysmorphoses

Chemical Profile and Biological Activity of Cherimoya (Annona cherimola Mill.) and Atemoya (Annona atemoya) Leaves

Annona cherimola (Cherimoya) and Annona atemoya (Atemoya) are tropical plants known for their edible fruit. Scientific data suggest that their leaves, used in traditional medicine in the form of teas or infusions without evidence of toxicity, contain several bioactive compounds. However, only Annona muricata among all the Annona species is currently used in the nutraceutical field, and its dried leaves are marketed for tea preparation. In this work, we explored the nutraceutical potential of Atemoya and Cherimoya leaves, by evaluating their chemical profile and functional properties. Phytochemical analyses showed large amounts of phenolic compounds, in particular proanthocyanidins, and identified 18 compounds, either flavonoids or alkaloids. Concerning biological activity, we found antioxidative properties correlated with polyphenols, and antiproliferative activity against HeLa and HepG2 cell lines correlated with alkaloids. The obtained results demonstrate the potential use of Annona cherimola leaves for the preparation of dietary supplements aimed to promote the physiological redox balance. Moreover, the varietal comparison suggests that two commercial cultivars (Campas and White) and the local Torre 1, better suit this purpose. On the other hand, among the studied cultivars, Campas and Torre 1 are also the richest in alkaloids and, in consideration of the anti-proliferative properties of their extracts, dietary supplements based on these cultivars might also have chemo-preventive effects

Chemical profile and biological activity of cherimoya (Annona cherimola Mill.) and atemoya (Annona atemoya) leaves

Annona cherimola (Cherimoya) and Annona atemoya (Atemoya) are tropical plants known for their edible fruit. Scientific data suggest that their leaves, used in traditional medicine in the form of teas or infusions without evidence of toxicity, contain several bioactive compounds. However, only Annona muricata among all the Annona species is currently used in the nutraceutical field, and its dried leaves are marketed for tea preparation. In this work, we explored the nutraceutical potential of Atemoya and Cherimoya leaves, by evaluating their chemical profile and functional properties. Phytochemical analyses showed large amounts of phenolic compounds, in particular proanthocyanidins, and identified 18 compounds, either flavonoids or alkaloids. Concerning biological activity, we found antioxidative properties correlated with polyphenols, and antiproliferative activity against HeLa and HepG2 cell lines correlated with alkaloids. The obtained results demonstrate the potential use of Annona cherimola leaves for the preparation of dietary supplements aimed to promote the physiological redox balance. Moreover, the varietal comparison suggests that two commercial cultivars (Campas and White) and the local Torre 1, better suit this purpose. On the other hand, among the studied cultivars, Campas and Torre 1 are also the richest in alkaloids and, in consideration of the anti-proliferative properties of their extracts, dietary supplements based on these cultivars might also have chemo-preventive effects

A positron trap and beam apparatus for atomic and molecular scattering experiments

An instrument has been designed and constructed to provide new insights into fundamental, low energy positron scattering processes. The design is based on the Surko trap system and produces a pulsed positron beam with an energy resolution of as good as 54 meV. The design and operation of the apparatus is explained, while the first experimental results from this apparatus have been demonstrated in recent publications.The authors would like to acknowledge the Australian Research Council for funding support, through the Centre of Excellence program, as well as the LIEF and Discovery funding programs

An atomic hydrogen beam to test ASACUSA's apparatus for antihydrogen spectroscopy

The ASACUSA collaboration aims to measure the ground state hyperfine splitting (GS-HFS) of antihydrogen, the antimatter pendant to atomic hydrogen. Comparisons of the corresponding transitions in those two systems will provide sensitive tests of the CPT symmetry, the combination of the three discrete symmetries charge conjugation, parity, and time reversal. For offline tests of the GS-HFS spectroscopy apparatus we constructed a source of cold polarised atomic hydrogen. In these proceedings we report the successful observation of the hyperfine structure transitions of atomic hydrogen with our apparatus in the earth's magnetic field.Comment: 8 pages, 4 figures, proceedings for conference EXA 2014 (Exotic Atoms - Vienna