Temporal phase-unwrapping of static surfaces with 2-sensitivity fringe-patterns

Here we describe a 2-step temporal phase unwrapping formula that uses 2-sensitivity demodulated phases for measuring static surfaces. The first phase demodulation has at most 1-wavelength sensitivity and the second one is G-times (G>>1.0) more sensitive. Measuring static surfaces with 2-sensitivity fringe patterns is well known and recent published methods combine 2-sensitivities measurements mostly by triangulation. Two important applications for our 2-step unwrapping algorithm is profilometry and synthetic aperture radar (SAR) interferometry. In these two applications the object or surface being analyzed is static and highly discontinuous; so temporal unwrapping is the best strategy to follow. Phase-demodulation in profilometry and SAR interferometry is very similar because both share similar mathematical models.

High-resolution low-noise 360-degree digital solid reconstruction using phase-stepping profilometry

In this paper we describe a high-resolution, low-noise phase-shifting algorithm applied to 360 degree digitizing of solids with diffuse light scattering surface. A 360 degree profilometer needs to rotate the object a full revolution to digitize a three-dimensional (3D) solid. Although 360 degree profilometry is not new, we are proposing however a new experimental set-up which permits full phase-bandwidth phase-measuring algorithms. The first advantage of our solid profilometer is: it uses base-band, phase-stepping algorithms providing full data phase-bandwidth. This contrasts with band-pass, spatial-carrier Fourier profilometry which typically uses 1/3 of the fringe data-bandwidth. In addition phase-measuring is generally more accurate than single line-projection, non-coherent, intensity-based line detection algorithms. Second advantage: new fringe-projection set-up which avoids self-occluding fringe-shadows for convex solids. Previous 360 degree fringe-projection profilometers generate self-occluding shadows because of the elevation illumination angles. Third advantage: trivial line-by-line fringe-data assembling based on a single cylindrical coordinate system shared by all 360-degree perspectives. This contrasts with multi-view overlapping fringe-projection systems which use iterative closest point (ICP) algorithms to fusion the 3D-data cloud within a single coordinate system (e.g. Geomagic). Finally we used a 400 steps/rotation turntable, and a 640x480 pixels CCD camera. Higher 3D digitized surface resolutions and less-noisy phase measurements are trivial by increasing the angular-spatial resolution and phase-steps number without any substantial change on our 360 degree profilometer.

Synchronous phase-demodulation and harmonic rejection of 9-step pixelated dynamic interferograms

We propose a novel synchronous phase-demodulation of pixelated interferograms using squared 3x3 phase-shifted unit-cells. This 3x3 unit-cell is tiled over the CCD image sensor to create a two-dimensional (2D) pixelated carrier. Our synchronous phase-demodulation uses this 2D carrier to demodulate the pixelated interferogram as in the standard 2x2 unit-cell case. The main motivation behind the use of a 3x3 pixelated carrier (instead of the usual 2x2) is its higher harmonic robustness, allowing one to demodulate intensity-distorted fringe patterns. The harmonic rejection robustness of our spatial 3x3 configuration equals the robustness of the temporal least-squares 9-step phase-shifting algorithm (PSA). In other words, extending from the usual 2x2 phase-shifting unit-cell to 3x3 unit-cells, one extends the harmonic rejection of the demodulation algorithm. Finally we also prove that our proposed 9-step, 3x3 pixelated carrier uses the 2D available spectral space more efficiently than using these 9-steps in a linear spatial-carrier configuration.

Harmonics rejection in pixelated interferograms using spatio-temporal demodulation

Pixelated phase-mask interferograms have become an industry standard in spatial phase-shifting interferometry. These pixelated interferograms allow full wavefront encoding using a single interferogram. This allows the study of fast dynamic events in hostile mechanical environments. Recently an error-free demodulation method for ideal pixelated interferograms was proposed. However, non-ideal conditions in interferometry may arise due to non-linear response of the CCD camera, multiple light paths in the interferometer, etc. These conditions generate non-sinusoidal fringes containing harmonics which degrade the phase estimation. Here we show that two-dimensional Fourier demodulation of pixelated interferograms rejects most harmonics except the complex ones at {-3(rd), +5(th), -7(th), +9(th), -11(th),…}. We propose temporal phase-shifting to remove these remaining harmonics. In particular, a 2-step phase-shifting algorithm is used to eliminate the -3(rd) and +5(th) complex harmonics, while a 3-step one is used to remove the -3(rd), +5<(th), -7(th) and +9(th) complex harmonics.

Co-ordination between leaf initiation and leaf appearance in field-grown maize (Zea mays): genotypic differences in response of rates to temperature

BACKGROUND AND AIMS

In maize (Zea mays), early flowering date, which is a valuable trait for several cropping systems, is associated with the number of leaves per plant and the leaf appearance rate. Final leaf number depends upon the rate and duration of leaf initiation. The aims of this study were to analyse the genotypic variation in the response to temperature of leaf appearance rate and leaf initiation rate, and to investigate the co-ordination between these processes under field conditions.

METHODS

Sixteen hybrids of different origins were grown under six contrasting environmental conditions. The number of appeared leaves was measured twice a week to estimate leaf appearance rate (leaves d(-1)). Plants were dissected at four sampling dates to determine the number of initiated leaves and estimate leaf initiation rate (leaves d(-1)). A co-ordination model was fitted between the number of initiated leaves and the number of appeared leaves. This model was validated using two independent data sets.

KEY RESULTS

Significant (P < 0.05) differences were found among hybrids in the response to temperature of leaf initiation rate (plastochron) and leaf appearance rate (phyllochron). Plastochron ranged between 24.3 and 36.4 degree days (degrees Cd), with a base temperature (Tb) between 4.0 and 8.2 degrees C. Phyllochron ranged between 48.6 and 65.5 degrees Cd, with a Tb between 2.9 and 5.0 degrees C. A single co-ordination model was fitted between the two processes for all hybrids and environments (r2= 0.96, P < 0.0001), and was successfully validated (coefficient of variation < 9 %).

CONCLUSIONS

This work has established the existence of genotypic variability in leaf initiation rate and leaf appearance rate in response to temperature, which is a promising result for maize breeding; and the interdependence between these processes from seedling emergence up to floral initiation.

[Diffuse primary malignant mesothelioma in abdominal cavity]

Two cases of diffuse malignant mesothelioma of abdominal cavity were analysed. These tumors arise from the peritoneum and are also found in the parietal and visceral pleura, pericardium and in vaginal tunic. All of them, infra or supra-diaphragmatic, are associated with asbestos exposure in at least 80% of cases. It is difficult to explain how inhaled asbestos induces peritoneal neoplasms. This aspects become very important in the diagnostic, basically why it is done at laparotomy or laparoscopy. When was proceed the biopsy of the lesions, and occasionally by identification of malignant mesothelial cells in ascitic fluid. In this two cases exposed considerations about the advanced phase of diagnostic are made, the diagnostic was performed in the majority of the collected cells, showing the advanced stage of the disease. At that time of diagnosis we observed poor evolution. We call attention to the importance of precancer diagnosis, the best chance to treatment options, always based on surgical resections, radiation or chemotherapy alone or combined. If the radical surgery is not possible, this patients must be treated by chemotherapy or radiotherapy, defined after complete staging of the disease.

Field orientation effects during 5.6-GHz radiofrequency irradiation of rats

Ketamine-anesthetized Sprague-Dawley rats were exposed in E and H orientations (long axis parallel to electric and magnetic fields, respectively) to far-field 5.6-GHz continuous-wave radio-frequency radiation (RFR). Power densities were used that resulted in equivalent whole-body average specific absorption rates of 14 W/kg in both orientations (90 mW/cm2 for E and 66 mW/cm2 for H). Irradiation was conducted to increase colonic temperature by 1 degree C (from 38.5 to 39.5 degrees C). During experimentation, arterial blood pressure and respiratory rate and colonic, tympanic, left and right subcutaneous (sides toward and away from RFR source), and tail temperatures were continuously recorded. Results showed no significant difference in the times required to cause a 1 degree C increase or to recover to the initial temperature when irradiation was stopped. Significant differences between E- and H-orientation exposure were seen in the patterns of localized heating. The tail and left subcutaneous temperature increases were significantly greater during E-orientation exposure, the tympanic site showed no difference, and the right subcutaneous temperature increase was significantly greater during H-orientation exposure. Under both exposure conditions, heart rate and mean arterial blood pressure significantly increased during irradiation; however, there were no significant differences between E and H orientation responses. These findings at 5.6 GHz are in contrast to the significant cardiovascular response differences between E- and H-orientation exposure noted during a previous study of irradiation at 2.45 GHz.

Thermal and physiologic responses to 1200-MHz radiofrequency radiation: differences between exposure in E and H orientation

Ketamine-anesthetized Sprague-Dawley rats were exposed to far-field 1200-MHz continuous wave radiofrequency radiation in both E and H orientations (long axis of animal parallel to electric or magnetic field, respectively). Power densities were used that resulted in equivalent whole-body specific absorption rates of approximately 8 W/kg in both orientations (20 mW/cm2 for E and 45 mW/cm2 for H). Exposure was conducted to repeatedly increase colonic temperature from 38.5 to 39.5 degrees C in both orientations in the same animal. Irradiation in E orientation resulted in greater colonic, tympanic, left subcutaneous (side toward antenna), and tail heating. The results indicated a more uniform distribution of heat than that which occurred in previous experiments of 2450-MHz irradiation in E and H orientation. A lack of significant differences in blood pressure and heart rate responses between exposures in the two orientations in this study suggest that greater peripheral heating, as was seen in the earlier study of 2450 MHz, is necessary for these differences to occur.

Objective assessment of topical anti-inflammatory drug activity on experimentally induced nickel contact dermatitis: comparison between visual scoring, colorimetry, laser Doppler velocimetry and transepidermal water loss

Four topical anti-inflammatory drugs were investigated for their effect on allergic contact dermatitis. Nickel dermatitis was chosen for its high incidence in European healthy volunteers. Experimental lesions were treated twice daily with two steroids, two non-steroidal anti-inflammatory drugs and a blank base for 4.5 days without occlusion. The influence of treatments was assessed by daily visual grading and one site was left untreated for comparison over the same period. To quantify drug activities objectively, skin colour (colorimetry), skin blood flow (laser Doppler velocimetry) and transepidermal water loss (evaporimetry) were measured before drugs were first applied, then 6 hr after the last application. As expected, only Dermoval cream significantly improved the spontaneous clinical evolution in comparison with the other creams (Hydrocortisone Aster à 1%. Parfenac, indomethacin 2.5% and Skinbase) and the untreated site. Colorimetric parameter a* (redness) and L* (luminance) showed more differences between treatments than the other criteria and a close relationship was obtained between these two parameters and skin blood flow, all three being highly correlated to visual grading. Transepidermal water loss appeared less related to clinical improvement but this parameter could prove helpful for detecting compounds which could be irritant to diseased skin.

Thermal and physiological changes in rats exposed to CW and pulsed 2.8 GHz radiofrequency radiation in E and H orientations

Ketamine-anesthetized Sprague-Dawley rats were exposed in both E and H orientations to far-field 2.8 GHz continuous-wave (CW) and pulsed (0.5 microseconds, 500 pps) radiofrequency radiation (RFR) at equivalent whole-body average specific absorption rates (SAR) of approximately 14 W/kg. Intermittent irradiation was performed in all four exposure conditions, in the same animal, to repeatedly increase colonic temperature from 38.5 to 39.5 degrees C. Tympanic, subcutaneous (sides toward and away from RF sources), colonic, and tail temperatures, electrocardiogram, arterial blood pressure, and respiratory rate were continuously recorded. The results revealed no significant difference between the thermal effects of CW and pulsed RFR exposure. The results did show significant differences between the thermal effects of E- and H-orientation exposure. H-orientation irradiation produced significantly faster colonic temperature increases and, with the exception of the tail, produced significantly greater localized heating in the anesthetized rat, and higher local SAR in rat carcasses than did E-orientation exposure. Under all exposure conditions, heart rate and blood pressure increased significantly during irradiation and returned to baseline when exposure was discontinued. Respiratory rate remained unchanged during irradiation. There were no significant differences between the effects of E- and H-orientation exposure, or between CW and pulsed irradiation, upon heart rate, blood pressure, and respiratory rate.

[Impact of the spraying of deltamethrin in a focus of leishmaniasis in Bolivia]

After one month of entomological observations to record pretreatment data, a sub Andean village of Yungas, Bolivia (alt. 1500 m) was sprayed at the beginning of the rainy season (January 1987). Houses were treated inside and outside with deltamethrin at 0.025 g/sq.m.; kennels, hen-houses and stacks of adobe were also sprayed in the same way. As a result of the treatment, Lutzomyia longipalpis, the local vector of visceral leishmaniasis, disappeared from houses and animal shelters for 9 and 10 months respectively. The impact of the treatment on the populations of Lu. nuneztovari and anglesi, the presumed vector of tegumentary leishmaniasis, was not obvious. As compared with pretreatment data, the rate of engorged females in houses decreased by two, and their density was also reduced. But these data are difficult to interpret due to the natural seasonal variation in density in this species. Moreover, the information from the control village did not correspond as expected. Lu. n. anglesi is a highly exophilic species in this area, a behaviour which could explain the limited impact of the treatment on this sandfly.