Breadboard of a Fourier-transform spectrometer for the radiation explorer in the far infrared atmospheric mission

In preparation for a possible space mission, a breadboard version named REFIR-BB of the Radiation Explorer in the Far Infrared (REFIR) instrument has been built. The REFIR is a Fourier-transform spectrometer with a new optical layout operating in the spectral range 100-1100 cm(-1) with a resolution of 0.5 cm(-1), a 7-s acquisition time, and a signal-to-noise ratio of better than 100. Its mission is the spectral measurement in the far infrared of the Earth's outgoing emission, with particular attention to the long-wavelength spectral region, which is not covered by either current or planned space missions. This measurement is of great importance for deriving an accurate estimate of the radiation budget in both clear and cloudy conditions. The REFIR-BB permits the trade-off among all instrument parameters to be studied, the optical layout to be tested, and the data-acquisition strategy to be optimized. The breadboard could be used for high-altitude ground-based campaigns or could be flown for test flights on aircraft or balloon stratospheric platforms. The breadboard's design and the experimental results are described, with particular attention to the acquisition strategy and characterization of the interferometer. Tests were performed both in laboratory conditions and in vacuum. Notwithstanding a loss of efficiency above 700 cm(-1) caused by the poor performance of the photolithographic polarizers used as beam splitters, the results demonstrate the feasibility of using the spectrometer for space applications.     

Perceptual color correction through variational techniques.

In this paper, we present a discussion about perceptual-based color correction of digital images in the framework of variational techniques. We propose a novel image functional whose minimization produces a perceptually inspired color enhanced version of the original. The variational formulation permits a more flexible local control of contrast adjustment and attachment to data. We show that a numerical implementation of the gradient descent technique applied to this energy functional coincides with the equation of automatic color enhancement (ACE), a particular perceptual-based model of color enhancement. Moreover, we prove that a numerical approximation of the Euler-Lagrange equation reduces the computational complexity of ACE from theta(N2) to theta(N log N), where N is the total number of pixels in the image.     

Aflatoxin B1 and clinoptilolite in feed for laying hens: effects on egg quality,mycotoxin residues in livers,and hepatic mixed-function oxygenase activities

Ninety-six laying hens were allocated to four groups administered different diets (group 0-0 received a complete diet, group 0-AF received a diet supplemented with 2.5 ppm of aflatoxin B1 [AFB1], group 2-0 received a diet supplemented with 2% clinoptilolite [CPL], and group 2-AF received a diet supplemented with 2% CPL and 2.5 ppm of AFB1) for 4 weeks to evaluate the effect of AFBI and/or CPL on egg quality and the ability of CPL to interact with the oral administration of AFB1. The possible effects of AFB1 on cytochrome P450-dependent hepatic mixed-function oxygenase (MFO) activities were also evaluated. Mycotoxin reduced yolk weight, while CPL influenced albumen percentage relative to that of eggs laid by chickens in group 0-AF Eggs laid by chickens in groups 0-AF and 2-AF had stronger shells and weighed less than the eggs of other groups. The eggs of treated groups were lighter in color than those of the control group (P < 0.01), and the tendency to yellowness in eggs was increased by CPL, probably through the affinity of red pigments for adsorbents and a consequent prevalence of yellow tonality. Color parameters might be connected with AFB1's interference with lipid metabolism and pigment deposition. The livers of hens in groups 0-AF and 2-AF showed very low mycotoxin concentrations that were significantly different (P < 0.01). The highest levels observed were those in the livers of the hens receiving the diet supplemented with the mycotoxin alone. AFB1 did not exert any significant effects on the hepatic MFO activities examined.     

Thermodynamic analysis of the reaction of barium chloride with water vapour from 1173 K to 1473 K

Equilibrium pressures of hydrogen chloride and water vapour over solid or liquid barium chloride have been measured between 1173 K and 1473 K. All other gases were excluded from the system. The corresponding equilibria were represented by the following reactions: BaCl₂(s) + H₂O(g) ? BaO(s) + 2 HCl(g), between 1173 K and 1235 K; BaCl₂(1) + H₂0(g) ? BaO(s) + 2 HCl(g), between 1235 K and 1473 K; $\text{3}\text{2}$ BaCl₂(1)(saturated with BaO) $\text{+ H}{}_2\text{O(g) ai}\text{1}\text{2}$ (BaCl₂ 2BaO)(s) + 2 HCl(g), between 1173 K and 1268 K; and $\text{4}\text{3}$ BaCl₂(1) (saturated with BaO) $\text{+ H}{}_2\text{O(g) ?}\text{1}\text{3}\text{(BaCl}{}_2\text{. 3BaO)(s) + 2 HCl(g)}$, between 1268 K and 1473 K. The equilibrium constants K_p fit satisfactorily a linear plot of In K_p versus reciprocal absolute temperature. Mean enthalpy and entropy values of the reactions studied in the temperature range investigated were obtained from the plot and compared to literature data and to the phase diagram of the barium chloride — barium oxide system. The reactions involved and the thermodynamics of reactivity of barium chloride with water are critically examined.     

Variability of reduced glutathione levels in Massese ewes and its effect on daily milk production

The variability of the erythrocyte concentration of the tripeptide glutathione was studied in four flocks of Massese sheep. A relationship was found between glutathione level and stage of lactation in which the second month showed the lowest content. Genotype at transferrin and haemoglobin loci was associated with glutathione levels. Homozygotes at the transferrin locus yielded higher levels, while the D allele at the same locus was associated with lower concentrations. Animals with haemoglobin AA showed higher contents of glutathione. Also, a negative correlation was found between daily milk production and glutathione level.     

A bee-inspired visual homing using color images

This paper presents a visual homing algorithm for autonomous robots inspired by the behaviour of bees and other social insects. The homing method presented is based on an affine motion model whose parameters are estimated by a best matching criterion. No attempts are made to recognize the objects or to extract 3D models from the scene. Improvements in the algorithm and in the use of colour information are introduced in order to enhance the efficiency of the navigation vector estimate. Tests and results are presented.     

Modeling and simulation of handling machinery with dynamic andstatic behavior of non-rigid materials

The modeling and simulation environment described allows the system engineer to design and simulate automated systems handling non-rigid materials taking into account their physical properties. The system's three main components include one which geometrically models both the workspace and the handling machinery, one which physically models and simulates the behavior of flat elastic and visco-plastics bulk types of non-rigid materials, and a robot off-line programming system. The second module, SoftLand, is based on the particle-based model and constitutes the innovative component     

Neural Networks for Autonomous Path-Following with an Omnidirectional Image Sensor

This paper presents a path-following system implemented with two different types of neural networks, that enables an autonomous mobile robot to return along a previously learned path in a dynamic environment. The path-following is based on data provided by an omnidirectional conical visual system, derived from the COPIS sensor, but with different optical reflective properties. The system uses optical and software processing and a neural network to learn the path, described as a sequence of selected points. In the navigation phase it drives the robot along this learned path. Interesting results have been achieved using low cost equipment. Test and results are presented.     

Autophagy and Mitophagy Promotion in a Rat Model of Endometriosis

Endometriosis is a gynecological condition affecting patients in reproductive age. The aim of this paper was to assess the effects of the autophagy and mitophagy induction in a rat model of endometriosis. Endometriosis was induced by the injection of uterine fragments, and rapamycin (0. 5 mg/kg) was administered once per week. One week from the induction, rats were sacrificed, and laparotomy was performed to collect the endometriotic implants and to further process them for molecular analysis. Western blot analysis was conducted on explanted lesions to evaluate the autophagy pathway during the pathology. Elevated phospho-serine/threonine kinase (p-AKT) and mammalian target of rapamycin (mTOR) expressions were detected in vehicle-treated rats, while Beclin and microtubule-associated protein 1A/1B-light chain 3 II (LC3II) expressions were low. Additionally, samples collected from vehicle groups indicated low Bnip3, Ambra1, and Parkin expressions, demonstrating impaired autophagy and mitophagy. Rapamycin administration reduced p-AKT and mTOR expressions and increased Beclin and LC3II, Bnip3, Ambra1, and Parkin expressions, activating both mechanisms. We also evaluated the impact of the impaired autophagy and mitophagy pathways on apoptosis and angiogenesis. Rapamycin was administered by activating autophagy and mitophagy, which increased apoptosis (assessed by Western blot analysis of Bcl-2, Bax, and Cleaved-caspase 3) and reduced angiogenesis (assessed by immunohistochemical analysis of vascular endothelial grow factor (VEGF) and CD34) in the lesions. All of these mechanisms activated by the induction of the autophagy and mitophagy pathways led to the reduction in the lesions’ volume, area and diameter.     

A comparative study of high velocity oxygen fuel,vacuum plasma spray,and axial plasma spray for the deposition of CoNiCrAlY bond coat alloy

In the aerospace field as well as in the stationary gas turbine field, thermally sprayed coatings are used to improve the surface properties of nickel-super-alloys materials. Coatings are commonly used as bond coat and antioxidation materials (mainly MCrAlY alloys) and as thermal barrier coatings (mainly yttria partially stabilized zirconia). The purpose of the current study was to assess the properties of thermally sprayed bond coat CoNiCrAlY alloys comparing the performance of three different techniques: vacuum plasma spray (VPS), high velocity oxygen fuel (HVOF), and axial plasma spray (AxPS). The quality of the deposited films has been assessed and compared from the point of view of microstructural (porosity, oxide concentration, unmelted particles presence) and mechanical (hardness) characteristics. The surface composition and morphology of the coatings were also determined. Specific efficiency tests were performed for the three examined technologies. The highest quality coatings are obtained by VPS, but also high velocity oxygen fuel and AxPS sprayed films have interesting properties, which can make their use interesting for some applications.