Changes In Visual Appearance Research Articles

Effect of Sea Salts on Structural Concrete in a Tidal Environment

SummaryStructural concrete exposed to the tidal/splash zone of marine environments is always subjected to ambient external, as well as internal, action of seawater over its entire lifespan. The environmental loading causes maximum damage to structural concrete in the tidal/splash zone of marine environments where it experiences the concentrated effect of salt ions found in seawater in presence of atmospheric oxygen, carbon dioxide and other harmful gases. The gradual penetration of sea salt ions and the formation of expansive/leachable compounds leads to cracking, spalling and even structural distress. This paper presents a part of a durability study on the effect of sea salts on structural concrete exposed to simulated tidal/splash zone marine conditions over a period of one year. The concrete specimens cast from two different grades of concrete were exposed to seawater of different concentration under submerged, alternate wetting-drying and atmospheric state of exposure in a controlled humidity and temperature environment. Using accelerated test techniques, the deteriorative effects were measured by studying visual appearance, weight and volume change, compressive strength, permeability and stress-strain characteristics, and x-ray diffraction patterns of salt-attacked concrete specimens. The test data provide useful information regarding the durability of structural concrete exposed to the tidal/splash zone of marine environments.

Stability of extemporaneously prepared voriconazole ophthalmic solution

The stability of extemporaneously prepared voriconazole ophthalmic solution was studied. Voriconazole solutions (2% and 1%) were reconstituted from the i.v. formulation. After thorough mixing, 3-mL samples of each of the resulting 2% and 1% solutions were filtered into eyedroppers. Three samples for both solutions were analyzed in triplicate at each time point. The 2% voriconazole ophthalmic solutions were stored at 2-8 degrees C, 25 degrees C, and 40 degrees C. The 1% voriconazole eye drops were stored at 2-8 degrees C. The 2% voriconazole solution samples were analyzed at time 0 and at weeks 1, 2, 4, 8, 16, and 32. The 1% solution samples were analyzed at time 0 and at weeks 6 and 14. Stability was measured using high-performance liquid chromatographic analysis. The 2% voriconazole ophthalmic solution demonstrated excellent stability at 2-8 degrees C and 25 degrees C for up to 16 weeks. The voriconazole solution displayed no significant change in pH at all time intervals. No change in visual appearance or clarity was observed in the 2% voriconazole eye drops at any point of the study for all study temperatures. Voriconazole 1% solution was stable at 2-8 degrees C for up to 14 weeks. Voriconazole 2% (20 mg/mL) solution preserved with 0.01% benzalkonium chloride prepared as alternative antifungal eye drops was stable for 16 weeks when stored at 2-8 degrees C and 25 degrees C and for 8 weeks when stored at 40 degrees C, while voriconazole 1% solution was stable at 2-8 degrees C for up to 14 weeks.

TH-D-304A-08: Quantitative PET Imaging of Heterogeneous Tumors: The Influence of Patient Position On Recovered Activity

Purpose: Dose‐painting will require precise quantification of uptake within sub‐regions of heterogeneous tumors. We have measured and characterized the effect of patient positioning on heterogeneity within PET images for 2D and 3D acquisition. Methods and Materials: Position‐dependent variations in recovery coefficients (RC) were measured on a multi‐slice PET imaging system using a phantom of five P 18P F‐filled spheres: two10mm and 15mm diameter, one 5mm. Spheres of each size were repositioned in 1mm increments between acquisitions while two kept stationary. 2D and 3D coincident counts were acquired at 4 minutes‐per‐position, and images generated with iterative reconstruction protocols. Measured RC variations were used to calculate expected SUV changes within heterogeneous tumors, for patient positions sampled from distributions of axial, radial, and angular uncertainties associated with head and neck (HN) cancer.Results: For sub‐voxel shifts in axial direction, the peak‐to‐trough RC values (RCBPTB) in 2D mode were 41%, 8% for 5mm and 10mm diameter sub‐regions. In 3D mode, these axial RCBPTB values were 24% and 7%. RCBPTB for radial shifts were 31% and 14% for images acquired in 2D mode, and 37% and 12% for 3D acquisition. All RCBPTB for15mm spheres were within the noise background, as determined from measurements of the stationary spheres.Random adjustments of head position resulted in notable changes in visual appearance and spatial distribution within PET images. For a very heterogeneous HN tumor, estimated population correlation coefficient between images was 0.8 (n = 1000 images × 696 voxels). However, correlation between individual images ranged from 1.0 to 0.6. Conclusion: Reproducibility is necessary for quantitative PET imaging; stable and precise voxel values will result in reliable voxel‐based image analysis. However, sub‐voxel verification of position of tumor sub‐regions is impossible, so shift‐interpolated images, which correspond to more reproducible mean RC values, could potentially reduce this systematic uncertainty.

XPS and ToF-SIMS analysis of natural rubies and sapphires heat-treated in a reducing (5 mol% H 2/Ar) atmosphere

Surface effects on Mong Hsu rubies and Kanchanaburi sapphires after heat treatment in a controlled reducing atmosphere (5 mol% H 2/Ar) have been investigated using advanced surface science techniques including X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Visual appearance of the gemstones is clearly affected by the heat treatment in a reducing atmosphere. Kanchanaburi sapphires, in particular, exhibit Fe-containing precipitates after the heat treatment which have not been observed in previous studies under an inert atmosphere. Significant correlation between changes in visual appearance of the gemstones and variations in surface concentration of trace elements, especially Ti and Fe are observed. The XPS and ToF-SIMS results suggest that; (1) a reducing atmosphere affects the oxidation state of Fe; (2) dissociation of Fe–Ti interaction may occur during heat treatment.

Wood plastic composites weathering: Visual appearance and chemical changes

The effects of outside and accelerated (xenon-arc and UVA) weathering on the visual appearance and chemical changes of wood plastic composite (WPC) formulations based on high density polyethylene (HDPE) and polypropylene (PP) were investigated. Colorimetry, scanning electron microscopy, Fourier transform infrared spectroscopy (FT-IR), and pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) were employed in this study. The study showed that for both outside and accelerated weathering, longer exposure time increased the degree of color change (and lightness), carbonyl concentrations, and wood loss on weathered WPC surfaces. HDPE-based WPC exhibited decreased lightening, carbonyl concentrations, and wood content loss when compared to PP-based WPC. From this study, relationships between chemical and color changes that occurred during exterior weathering of HDPE-based WPC were established. Oxidation and degradation of wood lignin influenced WPC color changes (lightening) during weathering.

Formulation and characterization of a ten-peptide single-vial vaccine EP-2101, designed to induce cytotoxic T-lymphocyte responses for cancer immunotherapy

Effective vaccines that mediate clinical responses in cancer patients may require generation of broadly specific cytotoxic T lymphocytes (CTL) directed against multiple epitopes and tumor-associated antigens (TAA). Pursuant to this goal we developed a synthetic peptide vaccine, EP-2101, composed of 10 synthetic peptide epitopes and formulated in Montanide® ISA 51 adjuvant. Nine of the HLA-A*0201-restricted CTL epitopes were derived from five well-characterized TAA. The universal HLA-DR binding epitope PADRE® was also included for T-cell help. Herein we describe studies on the formulation and characterization of the EP-2101 vaccine which supports generation of a sterile single-vial emulsion using standardized processes. The physicochemical properties of the peptides were highly disparate and as such, solubilization studies were required to identify a process which supported sterile filtration of the EP-2101 peptide mix. A homogenization-based formulation process with Montanide ISA 51 and 0.5 mg/ml of each peptide was developed to generate a water-in-oil emulsion. Physical studies indicated the vaccine emulsion to be stable, with little change in visual appearance, viscosity and water droplet size for at least 3 months. The physical stability of individual peptides in the vaccine emulsion was demonstrated using HPLC and immunogenicity of the vaccine formulation was confirmed in HLA-A*0201/Kb transgenic mice where T-cell responses could be induced to all epitopes in EP-2101 following vaccination. Our study process is scalable for production of approximately 1.5 liters of potent experimental vaccine for preclinical animal toxicity and phase 1 clinical testing in patients with breast, colon or lung cancer.

Postmating changes in cuticular chemistry and visual appearance in Ectatomma tuberculatum queens (Formicidae: Ectatomminae).

In the ectatommine ant Ectatomma tuberculatum, the visual appearance of queens changes after mating and ovarian development in that their cuticle turns from shiny to matte. In this study, we have shown that this change seems to be caused by 15-fold accumulation of hydrocarbons, in particular heptacosane that covers the multiple grooves present on the cuticular surface creating a wax coat in mated fully fertile queens. Analyses of the scrapped wax revealed that it is composed largely of heptacosane. Peak-by-peak comparison of the cuticular hydrocarbon (CHC) composition of mated, virgin with developed ovaries and virgin with nondeveloped ovaries revealed significant differences between the queen groups. Although the total amount of the CHC of virgin queens with developed ovaries was not higher than virgin queens that did not have developed ovaries, the composition showed a shift toward the mated queen. While it is possible that the large accumulation of hydrocarbons may give extra physical and chemical protection to queens, we propose that the switch in the relative abundance of heptacosane and nonacosane and perhaps of other components is indicative of being a mating and fertility cue. This is the first report in social insects where external chemical changes are accompanied by changes in visual appearance.

The properties of bufadienolides-loaded nano-emulsion and submicro-emulsion during lyophilization

The aim of this study was to prepare two types of emulsions, bufadienolides-loaded nano-emulsion (BU-NE) and submicro-emulsion (BU-SE) which were separately prepared by ultrasonic-high-pressure homogenization (UHPH) and high-pressure homogenization (HPH) methods, and to try to stabilize the colloid systems by lyophilization. The lyoprotective effects of cryoprotectant carbohydrates during the freeze-thawing and freeze-drying cycles on the emulsions were investigated in detail. The lyophilized products were characterized with regard to their appearance and particle size by transmission electron microscopy (TEM), scanning electron microscopy (SEM), photon correlation spectroscopy (PCS) and zeta potential. The median diameter, polydispersity index (PI) and zeta potential of BU-NE and BU-SE were 43.5 nm versus 161.4 nm, 0.100 versus 0.143 and −19.7 to −26.2 mV versus −29.4 to −35.3 mV, respectively. With the same drug content (0.28 mg mL −1) BU-SE exhibited a higher entrapment efficiency than BU-NE. The optimum cryoprotectant for BU-NE and BU-SE was maltose (20%) and trehalose (20%), respectively. The median diameters (95.7 and 168.5 nm) of the rehydrated BU-NE and BU-SE were slightly increased. For both of them, the bufadienolides entrapment efficiency was reduced whereas the drug content was not. The lyophilized BU-NE and BU-SE powders were stable over a period up to 3 months with no change in visual appearance, reconstitution ability, particle size distribution and drug concentration. This shows that freeze-drying could be a promising method to stabilize the emulsions.

Demonstration of cue recruitment: change in visual appearance by means of Pavlovian conditioning.

Until half a century ago, associative learning played a fundamental role in theories of perceptual appearance [Berkeley, G. (1709) An Essay Towards a New Theory of Vision (Dublin), 1st Ed.]. But starting in 1955 [Gibson, J. J. & Gibson, E. J. (1955) Psychol. Rev. 62, 32-41], most studies of perceptual learning have not been concerned with association or appearance but rather with improvements in discrimination ability. Here we describe a "cue recruitment" experiment, which is a straightforward adaptation of Pavlov's classical conditioning experiment, that we used to measure changes in visual appearance caused by exposure to novel pairings of signals in visual stimuli. Trainees viewed movies of a rotating wire-frame (Necker) cube. This stimulus is perceptually bistable. On training trials, depth cues (stereo and occlusion) were added to force the perceived direction of rotation. Critically, an additional signal was also added, contingent on rotation direction. Stimuli on test trials contained the new signal but not the depth cues. Over 45 min, two of the three new signals that we tested acquired the ability to bias perceived rotation direction on their own. Results were consistent across the eight trainees in each experiment, and the new cue's effectiveness was long lasting. Whereas most adaptation aftereffects on appearance are opposite in direction to the training stimuli, these effects were positive. An individual new signal can be recruited by the visual system as a cue for the construction of visual appearance. Cue recruitment experiments may prove useful for reexamining of the role of experience in perception.

(42) Sun Exposures Impact the Postharvest Quality and Firmness of Harvested Bell Peppers

Temperature management of fresh products begins with proper handling at harvest. Inadvertent abuses, such as lengthy delays to cool or exposure of harvested product to the sun, can detrimentally impact postharvest quality. We used mature-green bell peppers to determine the periods of sun exposure (midday during August in Davis, Calif.) necessary to affect quality attributes (visual appearance, gloss, weight loss, and firmness). Peppers were evaluated after cooling, storage at 7.5 °C for 3 or 7 days, and storage plus 2 days at 20 °C. The impacts of sun exposure, although sometimes barely detectable after cooling, became more noticeable once the peppers were stored. The additional transfer period to 20 °C after storage further accentuated the impact of the exposure. Depending on the experiment, sun-exposed areas reached 45 to 55 °C within 1 hour. Peppers typically lost 0.4% to 0.5% and 1.0% to 1.3% weight during 1- and 2-hour exposures, respectively. Changes in gloss and firmness (whole fruit compression and pulp penetration) were preceded by changes in visual appearance. Exposure to the sun for 0.5 hour did not impact postharvest quality of peppers. Exposures from 1 to 1.5 hours usually resulted in changes apparent only after the storage period. Such exposures are problematic in commercial situations because these peppers are unlikely to be eliminated during sorting on the packingline. Exposures of 1.5 to 2 hours usually resulted in an immediate change in appearance (pitting, blistering, color change).

Seasonal variations in the ovaries of the great scallop (Pecten maximus) from western Norway

Changes in weight, histology and visual appearance of ovaries from a field population of Pecten maximus (Pectinidae: Bivalvia) were followed for one year. Ovaries containing fully-grown oocytes were found throughout the year, though the degree of filling varied. Spawning activity of varying intensity occurred from late March to September. Recovery with increase in gonad index followed the spawning in spring, but there were no signs of gonad growth during a stepwise decline in gonad index from June to September. Gonad index increased to a new maximum between October and December. Oogenesis seemed to be active in filled ovaries throughout the year, and no classical resting period with empty gonads was seen. Prior to and during the spring phytoplankton bloom, recruitment of young oocytes appeared inhibited in some ovaries, leading to increased accumulation of large oocytes.

Specialised structural descriptions for human body parts: Evidence from autotopagnosia

Previous accounts of autotopagnosia (e.g., Ogden, 1985; Pick, 1908; Semenza, 1988) propose that the disorder is attributable to deficits in “mental images,” visual body schema, or semantic representations. A recent account (Sirigu, Grafman, Bressler, & Sunderland, 1991b) posits deficits in visual structural descriptions of the human body and its parts, in the context of spared semantic and proprioceptivespatio-motor body representations, but provides no evidence bearing on the nature or format of the putatively damaged representation. We report data from a man with autotopagnosia consequent to lefthemisphere brain damage which bear directly on the nature of the representation impaired in the disorder. The subject, GL, is unable to localise body parts on himself or others, whether cued by verbal or visual input. In contrast, he uses body parts precisely in reaching and grasping tasks, correctly matches items of clothing to body parts, and localises the parts of animals and man-made objects without error. We also demonstrate that GL is unable to match pictured or real human body parts across shifts in orientation or changes in visual appearance, but can perform analogous matching tasks with animal body parts and man-made object parts. The data extend the account of Sirigu et al. (1991b) in suggesting that human body part localisation depends upon structural descriptions of human (but not animal) bodies that enable viewpoint-independent body part recognition and participate in the calculation of equivalence between the body parts of self and others across transformations in orientation.

Specialised structural descriptions for human body parts: Evidence from autotopagnosia

Previous accounts of autotopagnosia (e.g., Ogden, 1985; Pick, 1908; Semenza, 1988) propose that the disorder is attributable to deficits in “mental images,” visual body schema, or semantic representations. A recent account (Sirigu, Grafman, Bressler, & Sunderland, 1991b) posits deficits in visual structural descriptions of the human body and its parts, in the context of spared semantic and proprioceptivespatio-motor body representations, but provides no evidence bearing on the nature or format of the putatively damaged representation. We report data from a man with autotopagnosia consequent to lefthemisphere brain damage which bear directly on the nature of the representation impaired in the disorder. The subject, GL, is unable to localise body parts on himself or others, whether cued by verbal or visual input. In contrast, he uses body parts precisely in reaching and grasping tasks, correctly matches items of clothing to body parts, and localises the parts of animals and man-made objects without error. We also demonstrate that GL is unable to match pictured or real human body parts across shifts in orientation or changes in visual appearance, but can perform analogous matching tasks with animal body parts and man-made object parts. The data extend the account of Sirigu et al. (1991b) in suggesting that human body part localisation depends upon structural descriptions of human (but not animal) bodies that enable viewpoint-independent body part recognition and participate in the calculation of equivalence between the body parts of self and others across transformations in orientation.

Grandma, what a big beard you have! an exploration of the client's reaction to a change in the art therapist's appearance

This paper, written in the context of work with people with learning disabilities, explores the impact upon the therapeutic relationship of a change in the therapists visual appearance (in this case the growth of a beard) during the course of therapy. The principle that the image/art object in art psychotherapy embodies important transference material is validated through an analysis of the artwork (using examples of imagery made before and after the therapists change in appearance) of two clients who reacted differently to the same phenomenon. The evidence suggests that changes in the visual appearance of the therapist has the potential to significantly influence the organisational and transference structures of the art therapeutic session.

Survival and growth of Escherichia coli O157:H7 on salad vegetables.

The influence of modified-atmosphere packaging, storage temperature, and time on survival and growth of Escherichia coli O157:H7 inoculated onto shredded lettuce, sliced cucumber, and shredded carrot was determined. Growth of psychotrophic and mesophilic microorganisms and changes in pH and sensory qualities of vegetables, as judged by subjective evaluation, were also monitored. Packaging under an atmosphere containing 3% oxygen and 97% nitrogen had no apparent effect on populations of E. coli O157:H7, psychotrophs, or mesophiles. Populations of viable E. coli O157:H7 declined on vegetables stored at 5 degrees C and increased on vegetables stored at 12 and 21 degrees C for up to 14 days. The most rapid increases in populations of E. coli O157:H7 occurred on lettuce and cucumbers stored at 21 degrees C. These results suggest that an unknown factor(s) associated with carrots may inhibit the growth of E. coli O157:H7. The reduction in pH of vegetables was correlated with initial increases in populations of E. coli O157:H7 and naturally occurring microfloras. Eventual decreases in E. coli O157:H7 in some samples, e.g., those stored at 21 degrees C, are attributed to the toxic effect of accumulated acids. Changes in visual appearance of vegetables were not influenced substantially by growth of E. coli O157:H7. The ability of E. coli O157:H7 to growth on raw salad vegetables subjected to processing and storage conditions simulating those routinely used in commercial practice has been demonstrated.

Optical properties of a metal island film close to a smooth metal surface

Bright colors have been observed when a metal island film is deposited on top of a silver mirror with a separating quartz layer. For spacer layer thicknesses that are varied from 0 to 140 nm, the visual appearance changes from blue/black to a series of brilliant spectrumlike colors. The sequence is repeated similarly for higher interlayer thicknesses. The phenomenon is analyzed in terms of a stratified medium theory by using TEM data and an electromagnetic model for the optical constants of the metal island film. For island films with a sufficiently high absorbance (> 0.35), the spectra are characterized by two sharp minima where the reflectivity drops to values below l0(-3). The observed thickness dependence is analyzed in terms of a complex combination of the phase shifts caused by the island film, the spacer, and the relevant interfaces.

Texture Evaluation of Carpets Using Image Analysis

This paper explores in detail new image enhancement techniques for assessing tuft geometry and concomitant appearance changes in new and worn carpets. Using im proved algorithms and more advanced tuft geometry, saxony tufted carpets of nylon and polyester BCF yams are capable of being extensively and reliably characterized as to texture and changes in appearance with laboratory or floor wear. While still using a relatively low resolution grey level imaging system, the newly developed al gorithms demonstrate how tuft size distribution, number of tufts, evenness of tuft spatial distribution, and aspect ratio (shape factor) of tufts can be objectively measured. Statistical analysis confirms that customary wear levels, and their visual appearance change in carpet, can be separated and correctly grouped by these new techniques. Some limitations of these and other texture-sensitive image analysis techniques are also discussed.

Stability of amrinone and digoxin, procainamide hydrochloride, propranolol hydrochloride, sodium bicarbonate, potassium chloride, or verapamil hydrochloride in intravenous admixtures

The stability of amrinone and digoxin, procainamide hydrochloride, propranolol hydrochloride, sodium bicarbonate, potassium chloride, or verapamil hydrochloride in intravenous admixtures was studied. Admixtures of amrinone and digoxin were studied at one concentration. Amrinone admixtures with propranolol hydrochloride, sodium bicarbonate, potassium chloride, and verapamil hydrochloride were studied at two concentrations. In general, 0.45% sodium chloride injection was used as the diluent; 5% dextrose injection was also used for the procainamide hydrochloride experiments. Duplicate solutions of each test admixture and single-drug control admixture were prepared and stored for four hours at 22-23 degrees C under fluorescent light. Samples were analyzed by visual inspection, tested for pH, and assayed by high-performance liquid chromatography. Admixtures containing amrinone 1.25 or 2.5 mg/mL (as the lactate salt) and sodium bicarbonate 37.5 mg/mL precipitated immediately or within 10 minutes. No changes in pH or visual appearance were noted for amrinone admixtures with procainamide hydrochloride, digoxin, propranolol hydrochloride, potassium chloride, and verapamil hydrochloride. Appreciable degradation of both amrinone and procainamide was observed after four hours when the two were mixed in 5% dextrose. No degradation of amrinone or procainamide was seen when the 5% dextrose was replaced by 0.45% sodium chloride. Amrinone and sodium bicarbonate were incompatible in intravenous admixtures. Amrinone was compatible with digoxin, propranolol hydrochloride, potassium chloride, and verapamil hydrochloride. Amrinone and procainamide were compatible in 0.45% sodium chloride injection but not in 5% dextrose injection.

Stability of Milrinone and Digoxin, Furosemide, Procainamide Hydrochloride, Propranolol Hydrochloride, Quinidine Gluconate, or Verapamil Hydrochloride in 5% Dextrose Injection

The stability of milrinone and digoxin, furosemide, procainamide hydrochloride, propranolol hydrochloride, quinidine gluconate, or verapamil hydrochloride in 5% dextrose injection containing milrinone was studied. Milrinone admixtures with digoxin, furosemide, propranolol hydrochloride, quinidine gluconate, and verapamil hydrochloride were studied at two concentrations. Admixtures of milrinone and procainamide hydrochloride were studied at four concentrations. Duplicate solutions of each admixture and each control were prepared and stored in glass containers for four hours at room temperature (22-23 degrees C), under normal fluorescent lights. The samples were analyzed immediately by visual inspection, tested for pH, and assayed by high-performance liquid chromatography (HPLC). Milrinone 0.35 mg/mL-furosemide 4 mg/mL and milrinone 0.1 mg/mL-furosemide 5 mg/mL admixtures precipitated immediately after preparation and were not studied by HPLC. No changes in pH or visual appearance were observed in the remaining admixtures after storage at room temperature for four hours. Admixtures containing milrinone 0.175 or 0.2 mg/mL and procainamide hydrochloride 1, 2, or 4 mg/mL satisfied the USP standard for procainamide hydrochloride injection USP assay after one hour but failed this test in all cases after four hours. No degradation of milrinone was observed in any of the admixtures containing procainamide hydrochloride. Milrinone and furosemide are incompatible in 5% dextrose injection and should be administered separately. The remaining admixtures were compatible, and all except those containing procainamide hydrochloride were stable for four hours at room temperature.

Photographic demonstration of the annual nature of a varve type common in N. Swedish lake sediments

Several lakes in northern Sweden have laminated sediments, of which many are interpreted as varved (annually laminated). In one of these lakes, a core of the recent sediment has been sampled annually since 1979 (except 1984). These cores verify that one varve, comprising of a thick summer layer (often colour-banded) and a thin winter layer, is formed each year. The cores also show, that, other than compaction, no change in visual appearance of the individual varves takes place after they have been overlain by new varves.