Fluorescent Yellow Research Articles

Precision detection of cyanide, fluoride, and hydroxide ions using a new tetraseleno-BODIPY fluorescent sensor

A new chemosensor based on Seleno-BODIPY (4) was designed and synthesized for the rapid and sensitive detection of CN–, F−, and OH– ions in THF, exhibiting ultra-low detection limits of 26.26 nM, 43.05 nM, and 8.64 nM, respectively, through a turn-on fluorescent process. The seleno-funcionalization step was based on a novel methodology developed by our group, allowing direct functionalization of the BODIPY core. This procedure involves a quick reaction utilizing Ph2Se2 as a selenium source, BPO (benzoyl peroxide), and p-TSA (p-toluenesulfonic acid) in acetonitrile, enabling the production of the corresponding chalcogenated BODIPYs containing one to four selenium groups, demonstrating its versatility. The structure of BODIPY 4 was confirmed by HRMS, 1H, 13C, 77Se NMR, and IR spectra, and its photophysical properties were also evaluated. BODIPY 4 was applied to detect CN–, F−, and OH– ions in dual-mode detection (UV–Vis and fluorescence spectra), displaying a ratiometric response. The new probe exhibited a fast response time, visual color change from blue to fluorescent yellow, and high sensitivity and selectivity for these analytes over other selected anions. Mechanistic investigation through mass analysis revealed that the detection of these anions by BODIPY 4 occurs via an Aromatic Nucleophilic Substitution reaction with phenylselenide as the leaving group.

Effects of host plants and substrate colour on the oviposition behaviour of green lacewing Apertochrysa astur (Banks) (Neuroptera: Chrysopidae)

The Green lacewing, Apertochrysa astur also known as “aphid lion” is an efficient predator of various soft bodied insect pests. A laboratory experiment was conducted in Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu to observe the preference of A. Astur on their oviposition behaviour. Egg receiving sheets were pasted with black, amber, ash, parrot green, violet, red, light green, pink, blue, fluorescent yellow, sky blue, yellow, orange and white coloured papers. Among all the colours, females of A. astur preferred black colour as a substrate for laying eggs (19.6 per cent of eggs) followed by orange colour substrate (15.5per cent) while white was the least preferred colour (4.0 % eggs). Among the host plants examined, maximum number of eggs was laid in the coconut leaves infested with the invasive whiteflies followed by custard apple and banana. Therefore, whitefly infested coconut leaves and the black coloured substrate can be used in the mass production of A. astur in the laboratory.

An activatable AIEgen for imaging of endogenous H2S: Reticulation based H2S gas sensor

Novel 2,4-dinitrophenylether functionalized hydroxybenzothiazole derivative (HBT 3) has been synthesized and characterized for selective and rapid detection of H2S in aqueous medium, gas phase and live cells. The H2S induced thiolysis of 2,4-dinitrophenylether leads to morphological transformation in HBT 3 from spherical to reticulate with aggregation induced emission (AIE + ESIPT) at 550 nm (greenish yellow aggregates) as evidenced by optical, DLS, NMR and AFM studies. The HBT 3 can specifically detect H2S with limits of detection as low as 0.45 and 1.22 µM in CH3CN; 2.9 µM and 6.8 µM in 70% HEPES buffer–CH3CN solution. The HBT 3 based solution- and solid- supported point-of-care testing (POCT) kits have been explored for detection of 75–400 ppm H2S gas; 2.4 µg H2S with fluorescence color change from non-fluorescent to fluorescent yellow. HBT 3 has been successfully utilized for endogenous and exogenous detection of H2S in live L929 cells.

High visibility colored fabrics for normal trichromats and individuals with color vision defects in a sunset-simulated environment.

This study aimed to investigate the visibility of colors in congenitally color vision defect people using general and fluorescent colors in an environment simulating sunset to examine the standards for high-visibility safety clothing for general users. Twenty participants with normal trichromats, seven protanopes, and five deuteranopes were included, with mean ages (± standard deviation) of 21.0±1.0, 46,7±16.1, and 56.6±6.9 years, respectively. Dyed fabrics were used to evaluate visibility. We evaluated brightness and conspicuousness sensitivity by combining red, yellow-red, yellow, green, red-purple, blue, white, black, fluorescent yellow, and fluorescent orange. For brightness sensitivity, the combination of fluorescent yellow and white/yellow stripes was highly visible and significantly different from all other samples (p < 0.05). For conspicuousness sensitivity, the combinations of black/fluorescent yellow, black/yellow, black/white, black/yellow-red, and white/red-purple stripes were highly visible and significantly different from all the other samples (p < 0.05). Yellow light is most visible and even better when fluorescent. They are based on specific spectral sensitivity, and yellow is the most visible, even for congenitally colorblind individuals. Furthermore, with regard to color combinations, it was found that the contrast between two distinct light or dark colors, such as black, yellow, black, and white, is perceived to be equally noticeable by congenital color vision defect individuals. This suggests the possible further applications of safety clothing.

Horse vision and obstacle visibility in horseracing

Visual information is key to how many animals interact with their environment, and much research has investigated how animals respond to colour and brightness information in the natural world. Understanding the visibility of features in anthropogenic environments, and how animals respond to these, is also important, not least for the welfare and safety of animals and the humans they co-exist with, but has received comparatively less attention. One area where this is particularly pertinent is animal sports such as horseracing. Here there is a need to understand how horses see and respond to obstacles, predominantly fences and hurdles, as this has implications for horse and rider safety, however obstacle appearance is currently designed to human perception. Using models of horse colour and luminance (perceived lightness) vision, we analysed the contrast of traditional orange markers currently used on fences from 11 UK racecourses, and compared this to potential alternative colours, while also investigating the effect of light and weather conditions on contrast. We found that for horses, orange has poor visibility and contrast against most surroundings. In comparison, yellow, blue, and white are more conspicuous, with the degree of relative contrast varying with vegetation or background type. Results were mostly consistent under different weather conditions and time of day, except for comparisons with the foreground turf in shade. We then tested the jump responses of racehorses to fences with orange, fluorescent yellow, bright blue, or white takeoff boards and midrails. Fence colour influenced both the angle of the jump and the distances jumped. Bright blue produced a larger angle of takeoff, and jumps over fluorescent yellow fences had shorter landing distances compared to orange, with bright blue fences driving a similar but non-significant trend. White was the only colour that influenced takeoff distances, with horses jumping over white fences having a larger takeoff distance. Overall, our results show that current obstacle coloration does not maximise contrast for horse vision, and that alternative colours may improve visibility and alter behavioural responses, with the ultimate goal of improving safety and welfare.

Grandisol as an attractant for the sugar beet pest Bothynoderes affinis and data on other Lixinae species

AbstractAs a result of field tests in Bulgaria and Hungary, cis‐2‐isopropenyl‐l‐methylcyclobutane ethanol (racemic grandisol) is reported for the first time as an attractant for Bothynoderes affinis (Schrank) (Coleoptera: Curculionidae, Lixinae), a member of the pest weevil complex of sugar beet. Dose–response experiments in the field using Csalomon TAL (modified pitfall) traps (Plant Protection Institute, CAR HAS, Budapest, Hungary) showed that catches of B. affinis adults increased with increasing attractant dose. In a subsequent experiment studying the effect of trap color (white, blue, yellow, fluorescent yellow, and transparent) all traps with the lure caught more than non‐baited control traps, and the highest number of adults was recorded in transparent and yellow baited traps. Trap color had a significant effect on the number of B. affinis females captured. Transparent TAL traps baited with 1–10 mg grandisol applied on rubber dispensers are recommended for the detection and monitoring of B. affinis. In addition to the target species, 17 other Lixinae species were captured during the field experiments, demonstrating for the first time the possible role of grandisol in the chemical communication systems of some of these species. A second locality of Lixus punctiventris Boheman (Lixinae, Lixini) in Bulgaria is reported. TAL traps baited with grandisol might be a useful tool for surveying Lixinae diversity in different biotopes.

Yellow–green luminescent poly(vinyl alcohol) nanocomposite thick films as effective spectral manipulators

ABSTRACTHighly flexible and visibly transparent yellow–green fluorescent poly(vinyl alcohol) (PVA) based nanocomposite (NC) films with rubidium zincate (Rb2ZnO2) nano impregnates were developed through aqueous solution casting. The introduced rubidium zincate nanofillers impart UV shielding properties to PVA host, through UV to visible (fluorescent yellow–green) photon cutting. The rubidium zincate nanofiller impregnated PVA systems were also characterized for their structural, morphological, optical, and electrical behaviors by various analytical tools. The Fourier Transform Infrared (FTIR) and X‐ray diffraction (XRD) studies shed light on the changes in gross structural properties of PVA. WhileScanning Electron Microscopic (SEM) profiles support uniform filler dispersions, which aid high visible transparencies. Further, the UV–visible spectral measurements depict the changes in electronic band structure that validates novel fluorescent emission properties, established through fluorescent emission studies. The NC films show excellent visible transparency (72–84%), near hydrophobic surface wettabilities (ϴ = 82°–93°) and enhanced charge conduction, in addition to high flexibilities and UV photons induced fluorescent emission ( λEmi=585 nm). The yellow–green luminescent, Rb2ZnO2 nanofillers reinforced PVA NC films are effective spectral manipulators, which may be used as competent packaging materials for photonic display devices and to extend the short wavelength limit of solar cells. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46854.

Effect of geographical directions, height and the color of yellow traps in capture of Mediterranean fruit fly, Ceratitis capitata (Wiedemann, 1824) in citrus orchards

Mediterranean fruit fly, Ceratitis capitata (Wiedemann, 1824) (Dip.: Tephritidae) is one of the most destructive agricultural pests in the world. To replace chemical control methods, as well as the timing of the peak population of Mediterranean fruit fly, the yellow sticky vertical traps were used in this study. The research was carried out in some citrus orchards of various cities of Mazandaran province of Iran, during the four months from August to November 2016. To determine the best type of yellow color to trap this fly, four types of yellow colors with measured wavelength of reflection, including the fluorescent yellow (538 nm), lemon yellow (574 nm), yellow (602 nm) and amber yellow (641 nm), were used. Also, to determine the best geographical direction and appropriate height for installation of yellow cards, four cardinal directions and five different heights of 1, 1.5, 2, 2.5 and 3 m above ground level were determined and the cards were installed. The results of mean comparison of captured flies in different treatments showed that there are significant differences between all of them. The results indicated that the fluorescent yellow, heights of 1.5 and 2 m, the south direction, and month October had the highest number of capture in yellow cards.

A Perceptual Analysis of Standard Safety, Fluorescent, and Neon Colors

Twenty-six standard safety colors specified by the American National Standards Institute (ANSI), International Standards Organization (ISO), and the Federal Highway Association (FHWA) were compared to seven fluorescent and neon colors on perceived hazard and perceived importance. Results indicated that the fluorescent orange, ANSI red, fluorescent yellow, FHWA red, fluorescent yellow green, and ISO red were the highest rated colors on perceived hazard. ANSI red, FHWA red, ISO red, fluorescent orange, fluorescent yellow, and fluorescent yellow green were rated the highest on perceived importance. The implications of these findings and the potential use of fluorescent colors in product warnings are discussed.

Introduction to Colorimetric Analysis for Assessment of Carotenoid Pigments in Squash Germplasm

Carotenoids of squash play an important role in human health by acting as sources of provitamin A or as protective antioxidants. Among the 60 accessions of squash germplasm, fluorescent yellow and yellow types of flesh color got the highest count, followed by the orange, whitish yellow and greenish yellow. The redness and yellowness values of the flesh powder ranged from -2.45 to 86.09 and from 13.77 to 39.80, respectively. While the lightness and the total color difference values of flesh color varied from 67.64 to 86.09 and from 19.77 to 51.79, respectively. Colorimetric values of redness and yellowness showed positive correlation, and the correlation coefficient (r) was as high as 0.7386. The five accessions represented each flesh color types, IT195043 (orange), IT136696 (fluorescent yellow), IT186365 (yellow), IT137963 (whitish yellow), and IT180449 (greenish yellow). The total amount of carotenoid contents was in the order of orange color (104.64 mg/100 g), greenish yellow color (70.82 mg/100 g), fluorescent yellow color (32.41 mg/100 g), yellow color (8.73 mg/100 g), and whitish yellow color (4.73 mg/ 100 g). Both lutein and β-carotene were the predominant pigments of carotenoids, and lycopene was only separated and identified in the orange color flesh. According to the results, colorimetric analysis can aid breeders interested in increasing carotenoid content in squash, which could be accurately measured using a simple, reliable, and cost- and labor-efficient method for the evaluation of carotenoid pigments.

Comparison of sticky and non-sticky trap designs baited with the pheromone for catching the olive flyBactrocera (Dacus) oleaeGmelin

Sticky “cloak” traps (CSALOMON® PAL) baited with the synthetic pheromone racemic 1,7-dioxaspiro[5.5]undecane were most efficient among the trap designs tested for catching male olive fly Bactrocera (Dacus) oleae Gmelin (Diptera, Tephritidae) in field tests in Croatia. Colour cues did not influence male catches. Consequently transparent sticky “cloak” traps baited with pheromone appear to be the best choice for detection and monitoring of males of the olive fly in Croatia. Female flies did not respond to the pheromone, however, were weakly attracted to the visual cues of yellow and fluorescent yellow.

A Comparison of Pan Trap and Intensive Net Sampling Techniques for Documenting a Bee (Hymenoptera: Apiformes) Fauna

Recent interest in pollinator sampling, often motivated by concerns about pollinator decline, has led to the increased use of standardized sampling protocols based on passive insect traps. Compared with netting insects at host plants, these protocols have the potential to limit some types of sampling bias, such as those associated with a researcher's observational and netting skills. The most commonly deployed recent protocol is the use of colored pan traps (bowls) filled with soapy water (Aguiar and Sharkov, 1997; Calbuig, 2001; Cane et al, 2000; Leong and Thorp, 1999; Toler et al, 2005). Insects approach the bowls, land on the water, and drown. The method is particularly good at catching numerous species of bees, but can also be effective for capturing various flower-visiting flies, skippers and a wide range of other insect taxa. As a bee sampling device, pan traps have several known biases: they catch bumble bees, honey bees and bees in the genus Colletes much less frequently than expected by their perceived abundance (e.g., Toler et al, 2005). Pan traps are especially good at catching halictid bees (Family Halictidae). Because of these biases, researchers sometimes use a modest amount of net collecting on flowers to accompany pan traps. Other potential biases remain to be studied, such as whether the effectiveness of pan traps is inversely related to flower abundance, a bias suspected by several researchers but not yet studied. Based on their pan-trapping study, Toler et al (2005) concluded that the predominant flower color in the plant community did not influence the relative attractiveness of particular pan trap colors, but they did not study the effect of floral abundance per se. Depending on a researcher's interest in deploying pan traps, these biases may or may not generate concern. Pan traps seem very well suited to testing for the presence of particular bee species in the community (Leong and Thorp, 1999), including many parasitic bee species that are seldom caught at flowers. They also provide a very valuable tool for augmenting other collecting methods, especially when there are few host plants to sample (e.g., early spring). Work by Cane et al. (2000) included a comparison of pan traps versus intensive netting to sample the very diverse and well known flower-visiting insect fauna of creosote bush. These workers concluded that pan trapping was of limited use in detecting the creosote bush fauna because of numerous species caught by netting but not by pan traps. Pan traps did catch many bee species not netted at creosote bush, however. Because netting in that study was restricted to creosote bush, there was no basis to compare the relative effectiveness of netting versus pan trapping for sampling a local bee fauna in the wider flower-rich community. In 2002 in northern Virginia, we carried out an intensive netting/observational survey of floral visitors within one hectare plots at Blandy Experimental Farm, an ecological experiment station of the University of Virginia. The sampled habitat was an open field and the sampling protocol comprised net sampling on the six most prominent plant species in the community from 8:00-16:00 hrs Eastern Daylight Time. Each plant species was surveyed for a total of 2.25 hrs, spread equally across the sampling period. Each of three researchers sampled all plant species in succession, one species at a time, three times across the sampling period (8:00-10:00, 11:00-13:00, 14:00-16:00). Survey periods lasted 15 mins per plant species per researcher, with researchers moving through the entire plot during that period. Bee species that could be recognized on the wing (e.g., Apis mellifera) were noted but not captured. To compare the effectiveness of pan trapping to such an intensive netting protocol at one of our sites, we placed a line of 30 pan traps (6 oz Solo bowls painted fluorescent blue, fluorescent yellow, or left white) in a diagonal line across the plot,

DEVELOPMENT OF THE MOST EFFECTIVE TRAP TO MONITOR THE PRESENCE OF THE CACTUS MOTH CACTOBLASTIS CACTORUM (LEPIDOPTERA: PYRALIDAE)

Various trap specifications were evaluated to identify the most effective trap for capturing wild male Cactoblastis cactorum (Berg). All traps were baited with virgin female C. cactorum and, except for the first comparison of trap type, a standard wing trap was used in all experiments. Although wing traps captured more males than did the other trap types (delta or bucket), the differences were not significant. However, significantly higher numbers of males were captured in wing traps placed 2 m above ground than traps at 1 m or 0.5 m, and wing traps baited with four virgin females caught significantly more males than wing traps baited with a single female. Differences in number of males captured by young and old females were not significant, but more than twice as many males were captured in traps baited with one-day-old females than traps baited with four day old females. In addition, there were no significant differences in number of males caught in unpainted, white, wing traps and wing traps painted one of eight different colors (flat white, black, dark green, fluorescent green, yellow, fluorescent yellow, orange, or blue), although, more males were captured in the unpainted wing traps. The results presented here suggest that the best trap currently available to monitor C. cactorum is a standard (unpainted) wing trap, placed at a height of 2.0 m aboveground, and baited with four newly emerged females.

Legibility Distances of Fluorescent Traffic Signs and Their Normal Color Counterparts

It is well known that fluorescent traffic signs have a daytime conspicuity that is far superior to that of normal color signs. This study was conducted to test the hypothesis whether adding the property of fluorescence, while leaving all (or in practical terms most) other sign features the same, does increase the legibility distance. Six diamond-shaped signs were fabricated and laminated with the normal colors on one side and their fluorescent color counterparts on the other. The investigated sign background colors included yellow, fluorescent yellow, fluorescent yellow green, pink, fluorescent pink, purple, and fluorescent purple. Four of the six signs used Landolt rings to avoid word familiarity issues. A pedestrian-crossing symbol sign and a “Plant Entrance” warning sign were used in addition to the Landolt ring signs. It was found that fluorescence actually did statistically significantly increase the legibility distances. However, the actual increases were fairly small from a practical point of view, ranging from 5.3 to 15.9 percent when adding the property of fluorescence. In general, for negative and positive contrast signs where both the legend and the background are fluorescent, a slight increase in the legibility distance can be expected. Note that the illumination conditions used (on a fair day) represent worst-case scenarios for fluorescent colors. Larger percent increases in legibility distance may be expected when using fluorescent colors during the time of twilight, overcast days, and daytime in inclement weather.

Visual Detection and Recognition of Fluorescent Color Targets Versus Nonfluorescent Color Targets as a Function of Peripheral Viewing Angle and Target Size

Daytime conspicuity of targets with fluorescent and nonfluorescent backgrounds as a function of the peripheral angle and the target size was investigated in the field. The resulting peripheral detection and recognition data may prove relevant to, for example, a bicyclist or a pedestrian approaching a driver at an intersection from a side street, or to a construction worker approaching a driver in a road construction site. Two groups of nine young, healthy subjects were used. White, blue, green, red, fluorescent red, fluorescent yellow-green, yellow, fluorescent yellow, orange, and fluorescent orange were presented at peripheral angles to the right of the line of sight. The targets were presented at a radial distance of 30 m (100 ft) from the front bumper of the car at the selected peripheral angle. The subjects were seated in a stationary car and the targets were visible for 2 sec. Each subject provided a total of 180 observations. The results of this study indicate that the fluorescent color targets (especially the fluorescent yellow-green) were considerably better-detected peripherally than their nonfluorescent counterparts. Furthermore, for some peripheral angles fluorescent yellow-green was among the top three best-recognized colors. On the basis of the results of this study, it may be concluded tentatively that to maximize daytime conspicuity for peripheral detection and recognition, highly conspicuous fluorescent colors such as fluorescent yellow-green, along with a fairly large target size, should be selected. It appears that however conspicuous a color is alone, if the target is too small for the visual angle subtended, the color will not be well detected or recognized, especially at larger peripheral viewing angles.

Conspicuity Advantage of Fluorescent Color Targets in the Field

Daytime conspicuity of fluorescent and non-fluorescent color targets was investigated in the field against a green background in terms of visual detection and recognition, as a function of the peripheral angle and the target size. Two groups of 9 young, healthy subjects each were used. The colors white, blue, green, red, fluorescent red, fluorescent yellow-green, yellow, fluorescent yellow, orange, fluorescent orange were presented for 2 seconds at a radial distance of 30m under the peripheral viewing angles of 10°, 20°, 30° for group 1, and 30°, 40°, 50° for group 2. The target sizes 0.076m x 0.152m, 0.114m x 0.229m, and 0.152m x 0.305m were used in group 1, and 0.114m x 0.229m, 0.152m x 0.305m, and 0.229m x 0.457m were used in group 2. Fluorescent color targets (especially fluorescent yellow-green) were better peripherally detected than the non-fluorescent color targets. White, blue, and green were better recognized but exhibited relatively poor peripheral conspicuity. Therefore it appears that if one wants to maximize the peripheral daytime conspicuity, both highly conspicuous fluorescent colors along with a fairly large target size should be selected. Such a target configuration may for example be needed to attract a driver's attention in situations where a target is located in an observer's visual periphery (peripheral angle &gt; 20°), for example a target approaching a driver at an intersection from a left or right side street.

Capture of Mediterranean Fruit Flies (Diptera: Tephritidae) Using Color Inserts in TriInedlure-Baited Jackson Traps

Tests of the capture of wild Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were made using a commercially produced adhesive paper available in several different colors as an insert in trimedlure-baited Jackson traps. Colors tested included fluorescent orange, fluorescent yellow, fluorescent light green, dark green, black, and white. These inserts were compared with the standard white inserts, which use sticky material that is manually applied. Tests were conducted in both citrus groves and coffee fields in Guatemala, and in a coffee field in Hawaii. Generally, inserts made with the fluorescent colors captured more flies than those with nonfluorescent colors. Traps with light green inserts captured a higher percentage of total flies than did traps with the standard white inserts in 3 of the 4 trials. Traps containing either yellow or orange inserts captured significantly more flies than the standard white insert in 2 of the 4 trials. Traps containing black inserts tended to catch a relatively low percentage of flies. There were differences in host species, host fruit availability, and fruit fly population levels among the various trials. These factors may influence the role of color cues in the capture of male flies by trimedlure-baited traps.

Retention of Jet-Injected Marks on Juvenile Coho and Sockeye Salmon

Abstract Juvenile coho salmon Oncorhynchus kisutch and sockeye salmon O. nerka were marked by jet injection to determine mark retention of three substances: Alcian Blue dye, black india ink, and acrylic paint (red, fluorescent yellow, and fluorescent orange). Fish were marked on the caudal fin and then held for 40 weeks in flow-through freshwater tanks. Coho and sockeye salmon both retained Alcian Blue and fluorescent orange marks best. The highest mark retention after 40 weeks was 73% for Alcian Blue marks on sockeye salmon. Overall mark retention was greater for orange-, yellow-, and black-marked coho salmon than for similarly marked sockeye salmon. Differences in growth rate—sockeye salmon grew about 7 mm more than coho salmon—probably contributed to the differences in mark retention between species. All colors appear suitable for short-term ( 6 weeks) marks, we recommend Alcian Blue dye or fluorescent orange or yellow acrylic paint for coho salmon and Alcian Blue dye fo...

Traps for Monitoring Pear Thrips (Thysanoptera: Thripidae) in Maple Stands and Apple Orchards

The effect of trap color and orientation on capture of adult pear thrips, Taeniothrips inconsequens (Uzel), was tested in Connecticut and Massachusetts. In single degree-of-freedom comparisons, vertically positioned fluorescent yellow rectangles caught the greatest numbers of thrips compared with all other vertically positioned hues tested, but numbers captured on fluorescent yellow did not differ significantly from captures on commercially available yellow, dark red, or white traps. Dark green and dark blue traps were least attractive to adults. In season-long trials of commercially available yellow, red, and white traps alone in apple and maple, yellow traps captured the most thrips. Fluorescent yellow traps in horizontal adhesive-down and 45°-adhesive-down orientations caught significantly fewer adult thrips than cylindrical, vertical, horizontal adhesive-up, or 45° adhesive-up orientations of the same hue. Upward-facing 45° orientations caught significantly more thrips than vertical rectangles of the same hue. Captures on vertical rectangles and on vertical cylinders did not differ significantly. We found that the most practical visual trap to estimate relative density and activity of pear thrips was a commercially available, nonbaited vertical yellow rectangle (16 by 19.5 em).

Fetal neocortical transplants grafted into cortical lesion cavities made in newborn rats receive multiple host afferents. A retrograde fluorescent tracer analysis

Several reports have demonstrated efferent projections from fetal neocortical transplants placed in the cerebral cortex of newborn rats. Fewer studies have examined transplant afferents, and these have primarily used techniques based on the axonal transport of horseradish peroxidase. In the present study, we extend these initial findings on transplant afferent connections by using retrogradely transported fluorescent dyes to demonstrate a topographic and more extensive pattern of cortical transplant afferents than has been previously reported. Fetal neocortical tissue was grafted into frontal cortical lesion cavities made by aspiration in newborn rats. At 1.5-10 months later, the fluorescent dyes Fast blue and Diamidino yellow were injected into the transplants. Subsequent histological analysis demonstrated numerous retrogradely labeled fluorescent neurons within the host thalamus and cerebral cortex as well as several other areas of the host brain. The neurons were primarily single-labeled and generally found in areas that normally project to the ablated area of the cortex. The topographic distribution of retrograde labeling in several animals with non-overlapping dye injections confined to the transplants suggests that the host projections were distributed selectively within the grafts. These results support and extend previous studies suggesting the use of fetal neocortical tissue in repair of the neonatally damaged central nervous system.