Academic literature on the topic 'Heat-induced coulor colour change'

Abstract The aim of the present study was to evaluate and compare the effect of thermal-cycling, mechanical brushing and beverage storage on the colour changes and surface roughness of conventional heat-polymerized and CAD/CAM PMMA used to fabricate complete dentures. A total of 100 specimens measuring 10 mm in diameter and 3 mm in thickness were fabricated from conventional PMMA resin (Heat-cured, Major. Base.20, Moncalieri, Italy) and CAD/CAM blocks (Opera system, Principauté de Monaco, French). The specimens were subjected to a combined surface treatment involving thermo-cycling, mechanical brushing, and immersed in either artificial saliva (AS), coffee, tea, Coca-Cola, or lemon juice. Colour differences (ΔE) and surface roughness (Ra) was determined using a spectrophotometer and non-contact profilometer, respectively. The data were analyzed using IBM SPSS v.20 (α = 0.05). Factorial ANOVA showed that independent factors, namely material, beverages, and the interaction between independent factors, significantly influenced ΔE (F = 76.862; p < 0.001) and surface roughness (F = 71.685; p < 0.001). The overall highest and lowest colour differences was obtained for CAD/CAM PMMA (ΔE = 1.93 ± 1.29) and conventional PMMA (ΔE = 1.41 ± 1.39) resins, respectively (p = 0.061). Conventional PMMA (1.22 ± 0.20) demonstrated significantly increased roughness compared to CAD/CAM PMMA (0.91 ± 0.17) (p < 0.001). Pearson correlation showed a low degree of correlation, which was non-significant for both the PMMA (r = 0.015; p = 0.917) and C-PMMA materials (r = 0.097; p = 0.505). CAD/CAM milled PMMA resins demonstrated greater colour change and lower surface roughness compared to conventional heat-polymerized PMMA resins. Specimens in tea and coffee demonstrated maximum colour changes and were perceivable by the human eye. On the contrary, specimens immersed in low pH acidic beverages namely Coca-Cola and lemon juice demonstrated maximum surface roughness.

To improve the protein nutritional quality of canola (Brassica napus L.) meal, further investigation of the effects of processing conditions and post-production treatments is desirable. The impact of barrel dry heat temperature (20 °C (cold press) and 100 °C (expeller)) and moist heat pressure (MHP) duration time on general nutritional properties, Maillard reaction product (MRP) formation, in vitro protein degradability, and molecular and microscopic structural characteristics of canola meals were investigated. Increased MHP duration reduced (p < 0.05) dry matter, soluble protein, rapidly degradable protein, yellowness (early MRP), whiteness (late MRPs), absorbance at 294 nm (intermediate MRPs), and amide I; and increased (p < 0.05) non-protein N, neutral detergent fibre, neutral detergent insoluble crude protein (CP), intermediately and slowly degradable protein, in vitro effective CP degradability, redness, degree of colour change, and browning. Increased dry heat temperature reduced (p < 0.01) CP and rapidly degradable protein, constricted amide II, reduced (p < 0.05) protein solubility in 0.5% KOH and increased (p < 0.05) acid-detergent fibre and intermediate MRPs. Browning index and redness exhibited potential as rapid indicators of effective CP degradability and soluble protein, respectively. Dry heat and MHP altered (p < 0.05) lipid-related functional groups. Dry heat affected napin solubility, and MHP altered cruciferin and napin solubility. Application of MHP induced the formation of proteolysis-resistant protein aggregates with crevices containing oil bodies. Induced changes may impact the supply of proteins and amino acids and subsequently the yield and composition (protein and lipid) of milk produced by dairy cows.

Ocean colour is recognised as an Essential Climate Variable (ECV) by the Global Climate Observing System (GCOS); and spectrally-resolved water-leaving radiances (or remote-sensing reflectances) in the visible domain, and chlorophyll-a concentration are identified as required ECV products. Time series of the products at the global scale and at high spatial resolution, derived from ocean-colour data, are key to studying the dynamics of phytoplankton at seasonal and inter-annual scales; their role in marine biogeochemistry; the global carbon cycle; the modulation of how phytoplankton distribute solar-induced heat in the upper layers of the ocean; and the response of the marine ecosystem to climate variability and change. However, generating a long time series of these products from ocean-colour data is not a trivial task: algorithms that are best suited for climate studies have to be selected from a number that are available for atmospheric correction of the satellite signal and for retrieval of chlorophyll-a concentration; since satellites have a finite life span, data from multiple sensors have to be merged to create a single time series, and any uncorrected inter-sensor biases could introduce artefacts in the series, e.g., different sensors monitor radiances at different wavebands such that producing a consistent time series of reflectances is not straightforward. Another requirement is that the products have to be validated against in situ observations. Furthermore, the uncertainties in the products have to be quantified, ideally on a pixel-by-pixel basis, to facilitate applications and interpretations that are consistent with the quality of the data. This paper outlines an approach that was adopted for generating an ocean-colour time series for climate studies, using data from the MERIS (MEdium spectral Resolution Imaging Spectrometer) sensor of the European Space Agency; the SeaWiFS (Sea-viewing Wide-Field-of-view Sensor) and MODIS-Aqua (Moderate-resolution Imaging Spectroradiometer-Aqua) sensors from the National Aeronautics and Space Administration (USA); and VIIRS (Visible and Infrared Imaging Radiometer Suite) from the National Oceanic and Atmospheric Administration (USA). The time series now covers the period from late 1997 to end of 2018. To ensure that the products meet, as well as possible, the requirements of the user community, marine-ecosystem modellers, and remote-sensing scientists were consulted at the outset on their immediate and longer-term requirements as well as on their expectations of ocean-colour data for use in climate research. Taking the user requirements into account, a series of objective criteria were established, against which available algorithms for processing ocean-colour data were evaluated and ranked. The algorithms that performed best with respect to the climate user requirements were selected to process data from the satellite sensors. Remote-sensing reflectance data from MODIS-Aqua, MERIS, and VIIRS were band-shifted to match the wavebands of SeaWiFS. Overlapping data were used to correct for mean biases between sensors at every pixel. The remote-sensing reflectance data derived from the sensors were merged, and the selected in-water algorithm was applied to the merged data to generate maps of chlorophyll concentration, inherent optical properties at SeaWiFS wavelengths, and the diffuse attenuation coefficient at 490 nm. The merged products were validated against in situ observations. The uncertainties established on the basis of comparisons with in situ data were combined with an optical classification of the remote-sensing reflectance data using a fuzzy-logic approach, and were used to generate uncertainties (root mean square difference and bias) for each product at each pixel.

Mussel beds form important intertidal matrices that provide thermal buffering to associated invertebrate communities, especially under stressful environmental conditions. Mussel shells are often colonized by photoautotrophic euendoliths, which have indirect conditional beneficial thermoregulatory effects on both solitary and aggregated mussels by increasing the albedo of the shell. We investigated whether euendolithic infestation of artificial mussel beds (Perna perna) influences the body temperatures of four associated mollusc species during simulated periods of emersion, using shell temperature obtained via non-invasive infrared thermography as a proxy. Shell temperatures of the limpet Scutellastra granularis and the chiton Acanthochitona garnoti were higher in non-infested than infested mussel beds during simulated low tides under high solar irradiance and low wind speeds. However, this was not the case for the limpet Helcion pectunculus or the top shell Oxystele antoni. Morphological differences in mollusc shape and colour could, in part, explain this contrast between species. Our results indicated that endolith-induced improvements in humidity and temperature in mussel beds could benefit associated molluscs. The beneficial thermal buffering offered by euendolithic infestation of the mussel beds was effective only if the organism was under heat stress. With global climate change, the indirect beneficial effect of euendolithic infestation for invertebrate communities associated with mussel beds may mitigate intertidal local extinction events triggered by marine heatwaves.

<p>Permanent makeup (PMU) is a frequently implemented cosmetic procedure performed by beauticians. From a technical point, PMU is considered a facial tattoo. Failed procedures or a change of mind can lead to the desire for removal. The purpose of this retrospective evaluation of patients who came to the clinic with the desire to remove PMU between 2011 and 2015 was to explore the problems, side effects, and results in order to define treatment guidelines for other doctors. We evaluated 87 individual cases in total. In treatable cases, i.e. 52 out of the 87 cases, laser treatments were performed using a nanosecond Q-switched neodymium-doped yttrium aluminium garnet (Nd:YAG) laser. It takes between 1-12 treatments to remove the PMU. In three cases, the colour of the PMU could not be removed by laser and remained after the treatment. In two cases, laser treatment had to be terminated due to colour changes towards the green-blue spectrum. Before PMU removal, laser test shots are urgently recommended as unforeseeable colour changes can cause severe aesthetically unpleasant results. Covered up PMU (skin colour) is particularly susceptible to changes in colour. Heat-induced shrinking of the eye area can cause an ectropium. Surgical solutions also have to be taken into consideration. The use of proper eye protection with intraocular eye shields is mandatory. This article is an attempt to set up some guidelines for the treatment of PMU removal.</p>

AbstractAutonomous polymers that report damage prior to loss of function and simultaneously self-heal are highly relevant for preventing catastrophic failures and extending the lifetimes of materials. Here, we demonstrate mechanochromic and thermally reprocessable thermosets that can be used for autonomic damage reporting and self-healing coatings. A mechanochromic molecule, spiropyran (SP), is covalently incorporated into thermoreversible Diels–Alder (DA) cross-linking networks. Mechanical activation of SPs in DA networks is confirmed by computational simulations and mechanical testing. The damaged areas of the polymers change colour, emit fluorescence signals, and completely recover after heat treatment. Because of the thermoreversible covalent networks, these polymers can be recycled up to fifteen times without degrading their mechanical, damage-reporting, or self-healing properties. Our autonomic material systems provide a new way to enhance the lifespans and reliabilities of thermosetting coatings, which also expands the range for practical applications of force-induced chemical reactions in polymers.

Since 2012, research has been conducted at the Lambrate Crematory (Milan). The aim was to analyse the cremains of dissected subject, decesead between 2012 and 2014 in order to collect information and match it with pre and peri-mortem data (sex, age, weight, height, pathologies, conservation condition of cadaver) and the parameters of combustion (temperature, oxygen percentage, duration of fire). The cremated remains of 173 adult Caucasians and 6 adult Asian producted by methan gas and electric ovens were analised. Of these, 162 had been dissected. Average age was 66 years old, height 168 cm, weight 76 kg and body mass index (BMI) 26,67. Cremains on average weigh 2738,04 g and 2276,90 g, with and without the fraction of fragments of <2 mm, respectively. Various measures were taken of the sex-pooled and of the male and female sub-samples in order to provide osteometric intervals standardized on the cremate sample. In particular: weight of each skeletal region; fragment dimensions; thickness of frontal, parietal and occipital bones and diaphysis of humerus and femur; antero-posterior and medium-lateral diameter of diaphysis and head vertical diameter and of humerus and femur. Most of the variables show statistically significant differences between males and females. Applicability of sexual metric methods, standardized on portoguese cremains sample, has been verified for present sample. The cremation process starts at a temperature of 600° C, reaching an average maximum temperature of 1026° C (min-max: 895° C – 1155° C), in about 30 minutes (30.10 ± 1.85; min-max: 5-50 minutes) and lasts on average for 80 minutes (min-max: 65-90 minutes). After the maximum temperature has been reached, the temperature falls off gradually to 600° C and the remains are recovered. Cremations in a gas oven determine the survival of 96.97% of sex diagnostic element, 75.72% of those diagnostic of age and shows 8,94% of deformations. Thanks to their protected position the auricular surfaces survive better than the pubic symphysis, in a ratio of about 2:1. The pubic symphysis seem show a higher survival in obese subjects. Deformations that do not appear to be related to the conservation of the cadaver or to combustion variables were observed in only 8.94% of cases. With regards to fragment colour, carbonized and grey residues were observed in more than 90% of subjects, representing a dishomogeneous physical characteristics and cadaver states of preservation. Chromatic differences taken by fresh bones were still recognizable after cremation: yellowish colour (2,5Y: 8/3, 8/4, 8/6, 8/8; 5Y: 8/3, 8/4, 8/6, 8/8 of on the Munsell Soil Chart) spreaded on the osseous surface, suggests body mummification or decomposition; brownish colouration (10YR: 6/6, 6/8, 5/4, 5/6, 5/8; 4/6; 3/6) may indicate a burial period of cadaver burial beforeprior to cremation. Among the cremains analysed were 168 subject with Striker circular saw autopsy cuts on the cranium and 38 with perimortem cranial fractures due to falls (16 cases), being struck by underground trains (3 cases), to accidents (13 cases), to blunt trauma (1 case) and to gunshot wounds (5 cases). Demographic, clinical and autopsy data with description and photographic documentation were available for these fractures. In five cases small cavities along the fracture lines were produced by cutter micro motor. Even after 90 minutes at a temperature of up to 1123° C, up to of trauma fragments with identifiable morphologies survived, particularly on thicker bones such as the occipital bone. The margins and surfaces of fractures can maintain their morphology or may be altered by further fracturing and warpings. Reddish colouration and opaque appearance of the surface cab be a criterion for perimortal lesion identification. The cremains of 3912 foetuses (representing 10 cremation events) from voluntary and therapeutic terminations of pregnancy were also investigated. Survival of all skeletal regions was observed with the exception of dental germs and carpal, tarsal, maxillary, ethmoid, lacrimal and nasal bones. The skull appears to be the most fragmented region while, in other regions, whole bones were found. It was possible to observe some pathological anomalies and measure 522 bones. The most widespread colouration is white due to calcination but black and grey can survive. Yellowish-red colouring was also observed an may reflect contact between the bones and organic tissues or blood (up to ten months may elapse between death and cremation). Fractures and deformations caused by fire were observed and comparable to those seen on the adults bones. Orthopaedic and odontoiatric prostheses from about 2700 cremations were analysed. The cremations resulted in about 586 kg of metallic residue, of which 490 kg (83.7%) was metal waste from coffins while prostetic devices accounted for 95 kg (16.3%). Types of prosthesis identified are: means of fracture fixation (intramedullary nails and plaques); prosthetic hip and shoulder (stems with and without heads, heads free and articular cups); prosthetic knee (femoral condyles and tibial plateau); heart valves, cables of pacemaker, vascular endoprosthesis; odontoiatric devices (endosseous implants; dental crowns; dental metal meshes; dental bridges). The colour tone (light and dark grey) and the different weight Indicate different types of metal: stainless steel or cobalt-chromiunm alloy (dark) ant titanium (light). The high number of prostheses found indicates the widespreas nature of surgical inverventions (about 50% of subjects with prostheses) and therefore, the potential importance of prostheses as an identifying element in forensic cases. Two experiments were conducted using muffle furnace to obtain information about teeth and perimortal lesions. In the first experiment 105 teeth divided into groups were exposed to temperatures of 50° C, 100° C, 150° C, 200° C to assess the impact of heat on root transparency, one of method used in the age estimation. The length of transparent root was measured both before and after treatment. Even at 50° C we observed changes in root transparency even if the morphological and colorimetric changes were not large. Hence, caution is suggested in using this method to determine age when subjects with apparently unaltered teeth have been in contact with heat or fire. In the second experiment 20 cow ribs were fractured with a hammer, 6 were pierced with a drill and 24 subjected to gunshot wounds. The bones were then subjected to a temperature of 800° C until calcination. Measueres pre and post-treatment showed significant changes in size, more so for blunt fractures and less so in the other two cases. The gunshot wounds also showed an increase in fractures originating from the margins of the bullet hole. In conclusion, this research has identified several critical points relating to combustion of bone that require further analysis.

As late as 1911, a leading American geographer could confidently assert that blacks in the United States would always live chiefly in "the warm, moist air of the Gulf and South Atlantic states," "where they find the heat and moisture in which they thrive"; nature decreed that few would ever settle and fewer survive in the North because they could not withstand the cold. Events, though, were contradicting this blend of racial and climatic determinism. Black migration from the South to the colder states was already substantial. It intensified dramatically during World War I. A boom in labor demand in industry, along with a near-cessation of the immigration from Europe that had once filled it, drew black and white southerners alike in unheard-of numbers to the manufacturing cities of the North. The black exodus to Kansas in 1879 and 1880 had briefly looked as if it would become just such a mass interregional movement of population. But the pioneer Exodusters had suffered from the drastic change in climate, most of all because it affected their livelihoods in farming. Their skills, which lay in cotton growing, were useless in Kansas, and their experience did little to encourage others to follow. The great northward migration of the early twentieth century was a migration not to new farmlands but to the cities for factory and service employment. The difference in climate between southern origin and northern destination did not matter much to it. White southern farmers, fearing the loss of cheap labor, warned departing blacks that they would find the winters of the North too bitter to endure. The new exodus proceeded all the same, and it discredited in the process the long-held idea that either race or habit always imposed a latitudinal pattern on human movement. The change in climate from South to North did mean discomfort or worse for many who undertook it. They suffered especially from the unaccustomed cold that few could afford stoves and fuel to ward off—though they had suffered too from inadequate shelter and clothing in the southern winter.

In 1978, K. O. Hill et al. [1] reported the first observation of photosensitivity in a germanosilicate fiber. Interest in understanding and optimizing this phenomenon was further heightened when Meltz et al. demonstrated that an external exposure method could form a grating for use in telecommunication windows [2]. Three mechanisms have been suggested in order to explain the refractive index changes induced in the fiber core. The first is based on a colour - center model [3]. The bleaching of the UV absorption band at 242nm leads through Kramers - Kronig relationship to a refractive index changes in the visible and infrared part of the spectrum. The second is based on UV induced stress relief of the fiber core [4]. The last model is based on structural modifications which induced compaction in the glass matrix [5]. Such UV induced densification has been already reported in preform plates as a change of volume leading to corrugations at the sample surface [6]. These experiments were performed on bulk sample. Therefore, it is of interest to confirm if compaction is photoinduced or not in photosensitive fibers. The aim of this work is to make microscopic investigations of the fiber core at the Bragg grating place in order to look if the UV exposure changes the structural or chemical properties of the material. The characterization of the grating structure photowritten in the optical fiber was realized by Atomic Force Microscopy on etched fibers.

“2-Color laser-induced fluorescence” (2-C LIF) is a novel quantitative temperature measurement method. This can eliminate the undesirable spatio-temporal fluctuation of excitation intensity occurred by light source and channel configuration using a ratio-metric technique with two fluorescence images. Therefore, it can obtain quantitative temperature distribution, and thus simplify temperature calibration in micro channel. In this paper, we applied it to micro-electrokinetic flow. Consequently, the spatial intensity error could be reduced to about 95% as compared with 1-Color LIF image. The temperature distribution in microchannel was quantitatively visualized at the high resolution 0.12×0.12 μm, high sensitivity 1.98%/K and high accuracy ± 0.27 K.

We have previously presented estimates of the effect of different parts of the surround on the appearance of a central test. This effect was measured by surrounding a central disk with a radially symmetric spatial sinewave that varied along a color line around midwhite. As the phase of the sinewave was changed uniformly in time, so that it appeared to drift towards the center, the appearance of the center changed cyclically in time. The induced modulation was nulled by adding real temporal modulation to the disk. The amplitude of the nulling modulation was measured for spatial frequencies of 0.05-2.0 c/deg at a drift rate of 1 Hz. The function relating the amplitude of nulling modulation to the spatial frequency of the surround was low-pass. If the amplitude of induced contrast were assumed to be a weighted sum of the effect of each pixel of the surround and the effect of each pixel proportional to the contrast amplitude at that pixel, then the spatial weighting function could be estimated by the Fourier transform of the measured nulling function divided by the extent of the surround. We now present tests of the first assumption. The surround consisted of pairs of radial sinewaves of different spatial frequencies. The two sinewaves were set to be inphase at the first surround pixel, and both were drifted at 1 Hz. The amplitude of induced contrast was measured as described above. The assumption of spatial additivity was tested by comparing the functions that relate the nulling amplitude to the spatial frequency of the paired surround sinewaves for each spatial frequency. The above measurements, combined with measurements of induced amplitude as a function of inducing amplitude, will enable us to characterize the spatial properties of color induction.

The use of liquid crystals as surface temperature sensors in transient wall heating experiments, to measure steady-state convective heat transfer coefficients, is becoming increasingly popular. This paper describes a simple graphical method to assist in the design of these experiments. The analysis assumes that the test specimen, perspex in the given example, behaves as a semi-infinite solid. Given an expected range of convective heat transfer coefficients, the experimenter can determine the optimum combination of liquid crystal colour change temperature, bounding wall thickness and experiment duration. It is also possible to determine the sensitivity of experimental uncertainty to the operating conditions and the physical properties of the bounding wall. Emphasis is given to the use of liquid crystal thermography but the methodology could be applied when other temperature measurement devices are employed.

Cancer cachexia is a systemic disease characterized by muscle and adipose loss that cannot be reversed by increasing caloric intake. Our previous research has shown insulin resistance precedes cancer cachexia in the C26 mouse model of cachexia, and a diet high in linoleic acid, the essential omega-6 polyunsaturated fatty acid, attenuates the C26-induced insulin resistance. Therefore, to better understand how dietary linoleic acid is improving insulin sensitivity, we characterized gene expression changes in three major tissues responsible for controlling insulin sensitivity: skeletal muscle, adipose, and liver. To do this male CD2F1 (Charles River, MA) were randomized to semi-purified diet (24% fat by weight) containing fat prominently from lard, or containing fat prominently from safflower oil (a linoleic acid-rich oil). One week after diet randomization, mice were inoculated with colon-26 (C26) adenocarcinoma cells (1.0E6 cells). 13 days after inoculation mice were euthanized and gastrocnemius skeletal muscle, epididymal white adipose tissue, and liver tissue were collected for total transcriptome analysis using poly-A enriched next generation RNA-sequencing. Differentially expressed genes were selected based on p-values < 0.05. There were no detectable differences in body weight or food intake between the two diets in mice with C26 tumors. Between the two diets 12 genes were differentially expressed in the muscle, while 57 genes were differentially expressed in the liver, and 314 genes were differentially expressed in adipose. A linoleic acid enriched diet had little effect on the skeletal muscle transcriptome but induced larger transcriptome changes in liver and adipose. This could suggest dietary linoleic acid increases insulin sensitivity through affecting metabolism in adipose and liver, rather than skeletal muscle. Determining these diet-induced transcriptome changes allows us to better target tissue-specific molecular mechanisms of linoleic acid in future research.

The UV radiation causes inks to fade. The ink fading will lead to the degradation of the visual appearance of printed imprints making them less attractive to the user. To deal with this that phenomenon, one of the solutions is to create a coating that could challenge these issues. In order to create efficient protective coating against UV induced degradation, nano scaled titanium dioxide (TiO2) wasl added to the commercial water-based varnish. To determine influence of the amount of TiO2, was homogenized in various weight ratios. The prepared nanocomposites were applied onto offset (lithography) prints made in accordance with Fogra PSO, i.e. ISO 12647-2:2013 on gloss coated paperboard. The samples have been subjected to artificial UV induced aging for 30 hours. The protective properties of the nanocomposite TiO2 coating was determined by calculating colorimetric and densitometric change on full tone and determining tone value change of half tones. The results showed that the prepared nanocomposite coating has relatively little effect on the printed colour of the samples. However, some coating compositions exceed the allowed tolerance ΔEab> 5, however in those cases the initial colorimetric value of WB (ΔEab) was close to the FOGRA PSO border value. The coatings with TiO2 will increase resistance to accelerated ageing on full and halftone. To conclude, this research has provided the new perspective on modulation possibilities of commercially available varnishes in order to cope a designated problematics and downsides of coatings which was, in this case, UV induced fading and degradation of visual appearance. The further research should investigate the applicability of this kind of modulated varnish in other coating techniques as well the use of other kind of nano sized compounds.

Dish/Stirling systems rely on accurate mirrors and alignment. Inaccuracies in alignment can lead to flux “hotspots” that can reduce performance and even damage the solar receiver. To improve the alignment process a procedure that can be used to align solar dish concentrator facets was developed on the second-generation (Mod 2) Advanced Dish Development System (ADDS) at Sandia National Laboratories in Albuquerque, NM. The previously used facet alignment method was based on the distant light source technique and required the dish to be pointed near the horizon while an observer located approximately 100 meters away views the image of a target and calls in adjustments to an aligner. At high sun elevation angles structural deflections inherent in any dish concentrator result in facet misalignments. To address these issues while allowing improved access to facet adjustments, an alignment technique that permits alignment at any elevation angle was developed and evaluated. This technique utilized a video camera and color target affixed on a lightweight tower at a distance near twice the dish focal length (2f) from the vertex of the dish, hence the name “color 2f”. The camera and target are centered on the optical axis of the concentrator. During the initial evaluation of the color 2f facet alignment procedure on the ADDS Mod 2 concentrator, no facet adjustments were made. Instead concentrator facet deflections were measured by taking and evaluating images of the dish reflecting the target while the dish was pointed at the horizon, 45 degrees elevation, and vertical. These images were compared to each other, to determine gravity induced pointing errors as the dish changes in elevation. Future implementations of the color 2f system could be used to align the system rather than simply diagnose it. The proposed approach has the potential to accurately align concentrators without large open land spaces, and to account for elevation-induced structural deflections. In this paper, the color 2f alignment technique is described along with the results from the gravity induced structural deflection study. Issues and recommendations for improvement of the 2f alignment system are also presented.

Permanent index changes, Δn, of the order of 10-4 at 633 nm are induced in germanosilicate optical fibers by exposure to light at 488, 266, and 240 nm.1-3 This photorefractivity has great potential in the fabrication of efficient grating-based devices for a wide range of WDM and lasing applications. It has been explained2 in terms of alterations in the UV absorption spectrum yielding (through the Kramers-Kronig relation) almost dispersion-free Δn values between 500 nm and 1.5 μm. The predominant cause is the movement of electrons from broken oxygen deficient Ge–Si bonds (associated absorption peak at 240 nm) to Ge(2) traps (when occupied by an electron an absorption peak appears at 213 nm) (see Fig. 1). The Ge–Si bonds can be broken by single-photon absorption of 240-or 266-nm light (permitting gratings of any period to be fabricated by side writing), or (much more slowly) by two-photon absorption (TPA) of 488-nm light. However, an undesirable side effect of 266-nm treatment is that the absorption induced for approximately the same Δn value is some two orders of magnitude larger than that obtained with 488-nm light (30 dB/m at 633 nm). This absorption is attributed to the creation of Ge(1) color centers,4 with a broad absorption peak centered at 281 nm and extending into the visible (Fig. 1). Because the balance between bleaching and trapping at Ge(1) and Ge(2) dopant sites is different for 266-nm light, it seemed possible that the population of Ge(1) centers could be depleted by 488-nm light, perhaps even enhancing the induced Δn.

Investigators at Triangle Research and Development Corporation (TRDC) have developed materials and applications for enhanced thermal management using both micro-and macro-encapsulated phase change materials (PCMs) since 1983; including: microPCM coolants, coatings, composites, fibers and PCM apparel. The PECS™ (Personal Environmental Control System) was developed for microclimate body cooling beneath NBC (Nuclear-Biological-Chemical) protective clothing for the US NAVY and USMC (Colvin, 1997 and 2000). Similar cooling apparel using 3–4mm macroPCM COOLBEADS™ were developed for costumed characters at two theme parks as well as potential use by firemen (Colvin, 1998). The results for these programs were reported at the 2000 and 2002 ASME ICEME (Colvin, 2000 and 2002). Civilian apparel has included 3.5 lb and 5 lb vests, a 1.5 lb cowl as well as a 1-lb collar, which suggested the potential for the microclimate cooling of athletes. Extreme heat during outdoor sporting events can be a major problem for athletes. Competitive runners, who often generate 700–900 W/m2, commonly deal with temperatures above 32.2°C (90°F) and a relative humidity greater than 80%. Natural cooling by evaporation and convection are often inadequate for a vigorously exercising athlete. Many athletes fatigue, drop out or have to wrap their chest and shoulders with ices and towels in order to finish the races. Ice and frozen gels, however, are uncomfortable, heavy, and can cause the blood vessels to constrict, thus restricting good blood circulation. Encapsulated PCMs can store 60 J/kg and the air spaces between the particles permit evaporation and convection as well as rapid thermal recharging. Development of an effective cooling collar could potentially permit competitive athletes to combat heat exhaustion and increase the body’s ability to dissipate heat.

Flow field near the turbine blade platform is very complex due to the secondary flow motions such as horseshoe vortices, passage vortices and endwall cross flows. It is therefore extremely difficult to predict the platform heat transfer distribution. As the secondary flows are largely affected by platform profile/shape, a number of investigators have studied different platform profiles to minimize aerodynamic loss and heat load. Understanding of the platform heat transfer has become especially critical in recent years, because of firing temperature increase and low NOx combustion requirement, as it is directly related to turbine durability. Three different axisymmetric platform profiles were designed and experimentally studied: flat profile, dolphin nose profile and shark nose profile. All of them were based on the existing engine hardware designs. The measurements were conducted in a high-speed linear cascade, which consisted of five blades and six flow passages. The test platforms were made of FR4 material and painted with Thermo-chromic Liquid Crystal (TLC). The test article was kept in the plenum located under the cascade at the pre-test condition. At the start of each test, the test blade/article was inserted into the cascade rapidly and then two CCD cameras recorded the color changes of the TLC on the platform surface. Engine representative Reynolds numbers were studied from 300,000 to 600,000 and the corresponding inlet Mach numbers were ranged from 0.12 to 0.24. The upstream section of the flat profile platform showed a typical flat plate heat transfer pattern with boundary layer development. The shark-nose and dolphin-nose platforms resulted in lower heat transfer coefficients on the upstream region compared to that for the flat profile, and the peak values moved slightly downstream from the leading edge due to possibly different secondary flow patterns. The heat transfer rate increased with increased Reynolds number for all three platform shapes, while the flat profile showed a higher increase rate. Zone averaged heat transfer distributions in addition to local values were also presented to show the effect of platform profile. In general, the flat profile platform resulted in a higher overall heat transfer rate than that for the other two profile platforms, which suggested that a good design of contoured profile platform could reduce the heat load and aerodynamic loss in gas turbine blade.

The broad objective of the project was to develop a feasible approach to combat diarrheal disease caused by ETEC through the development of a low-cost oral immunogen in tomato fruit, expressed in the context of a prototype tomato that would answer the shortcomings of plant oral vaccines, especially in terms of produce handling and control of gene escape. Specifically, the goals for Boyce Thompson Institute (BTI) on this project were to develop transgenic tomato lines that express the enterotoxigenic E. coli (ETEC) heat-labile enterotoxin (LT) subunits A and/or B for use in oral edible vaccines, and to optimize expression and assembly of these antigens in tomato fruits.LT-B is a useful vaccine antigen against ETEC disease, since antibodies against LT-B can prevent binding and delivery of the holotoxinLT. Mutant forms of the toxic LT-A subunit that have reduced toxicity can be co-expressed and assembled with LT-Bpentamers to form mutant LT (mLT) complexes that could be used as mucosaladjuvants for other oral vaccines. Work on the project is continuing at Arizona State University, after Dr. Mason moved there in August 2002. A number of approaches were taken to ensure the expression of both subunits and bring about their assembly inside the transgenic fruits. Initially, expression was driven by the fruit-specific E-8 promoter for LT-B and the constitutive CaMV 35S promoter for LT-A(K63). While LT-B accumulated up to 7 µg per gram ripe fruit, assembled LT-K63 was only 1 µg per gram. Since promoter activities for the two genes likely differed in cell type and developmental stage specificity, the ratios of A and B subunits was not optimal for efficient assembly in all cells. In order to maximize the chance of assembly of mLT in fruit, we focused on constructs in which both genes are driven by the same promoter. These included co-expression plasmids using the 35S promoter for both, while switching to attenuated mLTs (LT-R72 and LT-G192) that have shown greater potential for oral adjuvanticity than the initial LT-K63, and thus are better candidates for a plant-derived adjuvant. Other, more novel approaches were then attempted, including several new vectors using the tomato fruit-specific E8 promoter driving expression of both LT-B and mutant LT-A, as well as a dicistronic construct for co-expression of both LT-B and mutant LT-A genes from a single promoter, and a geminivirusreplicon construct. We describe in the Appendix the results obtained in transgenic tomato lines transformed with these constructs. Overall, each contributed to enhanced expression levels, but the assembly itself of the holotoxin to high levels was not observed in the fruit tissues. The Israeli lab’s specific objective was to develop transgenic tomato lines expressing the LTholotoxin antigen bearing attributes to prevent gene escape (male sterility and orange fruit color) and to improve the dissemination of the oral vaccine (long shelf-life tomato cherry fruit or tomato processing background). Breeding lines bearing a number of attributes to prevent gene escape were developed by combining material and backcrossing either to a tomato cherry background, or two different processing backgrounds. Concomitantly, (these lines can be utilized for the creation of any future oral vaccine or other therapeutic-expressing tomato, either by crosses or transformation), the lines were crossed to the holotoxin-expressing tomatoes received from the United States, and this transgenic material was also incorporated into the backcrossing programs. To date, we have finalized the preparation of the cherry tomato material, both non-transgenic (bearing all the desired attributes), and transgenic, expressing the holotoxin. The level of expression of LT-B in the cherry fruits was comparable to the original transgenic tomatoes. Since it was not higher, this would necessitate the consumption of more fruits to reach a desired dose. A final backcross has been made for both the non-transgenic and the transgenic material in the processing lines. Auxin sprays resulted in high percentages of fruit set, but the processing genotypes gave many puffed fruits.