scholarly journals Can Dental Office Lighting Intensity Conditions Influence the Accuracy of Intraoral Scanning?

Scanning ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Anca Jivanescu ◽  
Andrei-Bogdan Faur ◽  
Raul Nicolae Rotar
Keyword(s):  
Light Intensity ◽  
Extreme Values ◽  
Reference Model ◽  
Ambient Light ◽  
Light Conditions ◽  
Intraoral Scanner ◽  
Dental Office ◽  
Lighting Intensity ◽  
Office Lighting ◽  
Crown Preparation

The aim of this study was to evaluate the influence of different settings of ambient light intensity inside the dental office on the accuracy (trueness and precision) of an intraoral scanner (IOS). A full crown preparation was conducted on a resin molar which was scanned using a high resolution extraoral scanner to obtain a reference model. Six light settings were chosen based on the most clinically relevant light conditions inside the workspace, and the preparation was scanned using an intraoral scanner (PlanScan, Planmeca). The obtained data was analyzed using a professional 3D quality control software (Geomagic Control X). There was no statistically relevant difference between the groups when regarding trueness, although a slight influence of the light intensity could be observed on the trueness values. Regarding precision, the best results were obtained in the 3800 lux group, with the other groups presenting close values, excepting the extreme values (400 lux and 11 000 lux) groups that proved to be the most deficient.

scholarly journals Correlation Among Phenotypic Parameters Related to the Growth and Photosynthesis of Strawberry (Fragaria × ananassa Duch.) Grown Under Various Light Intensity Conditions

2021 ◽  
Vol 12 ◽  
Author(s):  
Hyo Gil Choi
Keyword(s):  
Light Intensity ◽  
Photosynthetic Pigment ◽  
Experimental Period ◽  
Control Treatment ◽  
Sugar Accumulation ◽  
Ambient Light ◽  
Light Conditions ◽  
Phenotypic Characteristics ◽  
Low Light ◽  
Photosynthetic Pigment Content

The objective of this study was to investigate characteristics of phenotypic parameters such as physiology, yield, and fruit quality responses of strawberry (Fragaria × ananassa Duch.) to various light intensity conditions (VLICs), and to determine the correlations among these phenotypic parameters. Strawberry plants were cultivated in a smart greenhouse separated into four areas, three of which were completely shaded by curtains from 20:00 until 10:00 (3 hS), 12:00 (5 hS), and 14:00 (7 hS), respectively. The fourth area was a non-shaded control treatment (0 hS). The ambient light intensities during the experimental period for the 0, 3, 5, and 7 hS treatments were 1,285, 1,139, 770, and 364 mol⋅m–2, respectively. Strawberry plants grown under low light intensity conditions experienced decreases in photosynthetic rate, stomatal conductance, and sugar accumulation compared to the 0 hS. Petiole generation and fruit yield were also sharply decreased in proportion to the degree of decrease in light intensity. In contrast, photosynthetic pigment content was shown to increase under low light conditions. Organic acid contents (excluding acetic acid) and leaflet size did not change significantly under low light conditions compared to the 0 hS. Changes to light intensity are considered to induce changes to the phenotypic characteristics of strawberry plants to favor growth using the energy and carbon skeletons obtained through respiration and photosynthesis. In the 7 hS treatment, where light intensity was drastically reduced, NPQ, qP, and RFd values as chlorophyll a fluorescence parameters were significantly lowered, which could indicate their measurement as an important technique to check the stress response of plants grown in low light conditions.

scholarly journals Improved CoChR Variants Restore Visual Acuity and Contrast Sensitivity in a Mouse Model of Blindness under Ambient Light Conditions

2019 ◽  
Vol 27 (6) ◽  
pp. 1195-1205 ◽  
Author(s):  
Tushar H. Ganjawala ◽  
Qi Lu ◽  
Mitchell D. Fenner ◽  
Gary W. Abrams ◽  
Zhuo-Hua Pan
Keyword(s):  
Visual Acuity ◽  
Mouse Model ◽  
Contrast Sensitivity ◽  
Ambient Light ◽  
Light Conditions

Ambient light intensity and direction determine relative attractiveness of yellow traps toRhagoletis indifferens(Diptera: Tephritidae)

2015 ◽  
Vol 147 (6) ◽  
pp. 776-786 ◽  
Author(s):  
W.L. Yee
Keyword(s):  
Light Intensity ◽  
Fruit Fly ◽  
Ambient Light ◽  
Laboratory Results ◽  
Yellow Traps ◽  
Relative Attractiveness ◽  
Variable Light ◽  
Sunlight Intensity ◽  
Trap Placement ◽  
Tephritid Fruit Flies

AbstractUnderstanding factors that influence attraction of tephritid fruit flies (Diptera: Tephritidae) to objects can lead to development of more sensitive traps for fly detection. Here, the objective was to determine if differences in attractiveness between two sticky yellow rectangle traps to western cherry fruit fly,Rhagoletis indifferensCurran, depend on ambient light intensity and direction. The translucent plastic Yellow Sticky Strip (YSS) was compared with the less translucent yellow cardboard Alpha Scents (AS). Flies were released inside a box or cage opposite a trap or traps illuminated from outside at different intensities to generate variable light passage. Regardless of type, the trap with greatest light passage was most attractive. When the same light intensity was shone on both traps, the YSS, which allowed greater light passage, was more attractive than the AS. When the light was inside a cage and shone onto the two traps in the same direction as approaching flies, the AS reflected more light and was more attractive. A field experiment generally supported light passage effects seen in the laboratory. Results suggest trap placement with respect to sunlight intensity and direction affects light passage and the attractiveness of yellow traps toR. indifferens.

scholarly journals Effects of alkalinity and salinity at low and high light intensity on hydrogen isotope fractionation of long-chain alkenones produced by <i>Emiliania huxleyi</i>

2017 ◽  
Vol 14 (24) ◽  
pp. 5693-5704 ◽  
Author(s):  
Gabriella M. Weiss ◽  
Eva Y. Pfannerstill ◽  
Stefan Schouten ◽  
Jaap S. Sinninghe Damsté ◽  
Marcel T. J. van der Meer
Keyword(s):  
Light Intensity ◽  
Environmental Conditions ◽  
Hydrogen Isotope ◽  
Isotope Fractionation ◽  
Emiliania Huxleyi ◽  
High Light Intensity ◽  
High Light ◽  
Light Conditions ◽  
Low Light ◽  
Long Chain

Abstract. Over the last decade, hydrogen isotopes of long-chain alkenones have been shown to be a promising proxy for reconstructing paleo sea surface salinity due to a strong hydrogen isotope fractionation response to salinity across different environmental conditions. However, to date, the decoupling of the effects of alkalinity and salinity, parameters that co-vary in the surface ocean, on hydrogen isotope fractionation of alkenones has not been assessed. Furthermore, as the alkenone-producing haptophyte, Emiliania huxleyi, is known to grow in large blooms under high light intensities, the effect of salinity on hydrogen isotope fractionation under these high irradiances is important to constrain before using δDC37 to reconstruct paleosalinity. Batch cultures of the marine haptophyte E. huxleyi strain CCMP 1516 were grown to investigate the hydrogen isotope fractionation response to salinity at high light intensity and independently assess the effects of salinity and alkalinity under low-light conditions. Our results suggest that alkalinity does not significantly influence hydrogen isotope fractionation of alkenones, but salinity does have a strong effect. Additionally, no significant difference was observed between the fractionation responses to salinity recorded in alkenones grown under both high- and low-light conditions. Comparison with previous studies suggests that the fractionation response to salinity in culture is similar under different environmental conditions, strengthening the use of hydrogen isotope fractionation as a paleosalinity proxy.

scholarly journals In vitro Comparison of Accuracy of Two Scanners Used in Dental Medicine

2019 ◽  
Vol 70 (7) ◽  
pp. 2344-2346
Author(s):  
Alexandru Victor Burde ◽  
Marius Manole ◽  
Radu-Septimiu Campian ◽  
Cosmin Sinescu ◽  
Sorana Baciu
Keyword(s):  
Experimental Model ◽  
Reference Model ◽  
Direct Consequence ◽  
Intraoral Scanner ◽  
Average Deviation ◽  
Virtual Reference ◽  
Significant Difference ◽  
Industrial Ct ◽  
In Vitro Comparison

This experimental study aims to highlight and compare the resolution and accuracy (trueness and fidelity) of an intraoral scanner and a laboratory scanner. In order to achieve the aim of this study, an experimental model consisting of a die with a standard preparation for a porcelain-fused to metal crown was manufactured from a physiognomic polymethylmethacrylate resin. The experimental model was scanned with an industrial CT to obtain the virtual reference model. Then, the die was scanned 15 times with each scanner. In order to asses trueness, comparisons were made with the virtual reference model, and for fidelity, the first scan in the series was compared with the following scans. In regards to the trueness of the scanners, the average deviation for the laboratory scanner is 4.31 and 17.34 mm for the intraoral scanner. When comparing the serial scannings� of the same die, the lowest recorded deviation is 6.4 mm for the laboratory scanner and 21.57mm for the intraoral scanner. For both fidelity and trueness, the F test demonstrates that there is a statistically significant difference between the scanners and the applied T-tests confirm the lower degree of error-rate generation by the laboratory scanner. The dimensional limitations imposed for the intraoral scanners have a direct consequence on their trueness and fidelity when compared to their laboratory counterparts.

scholarly journals Preservatives Stability: Stability Study of Parabens under Different Conditions of Stress Degradation

2020 ◽  
Vol 11 (3) ◽  
pp. 4187-4194
Author(s):  
Ismail Bennani ◽  
Madiha Alami Chentoufi ◽  
Miloud El Karbane ◽  
Ibrahim Sbai El Otmani ◽  
Amine Cheikh ◽  
...  
Keyword(s):  
Extreme Values ◽  
Stability Study ◽  
Wide Field ◽  
Direct Influence ◽  
Light Conditions ◽  
Influence Of Temperature ◽  
Stress Degradation ◽  
Quality Of Products ◽  
The Stability

Preservatives are used in a wide field of application to maintain the quality of products. They are used to deal with the chemical, physical and microbiological problems and the constraints of the development of several formulations. In this work, we tested the stability of antimicrobial preservatives which are the parabens under different stress degradation conditions to evaluate their degree of effectiveness. The tested parabens were incubated in different solutions at different pH, Temperatures, light conditions, and presence or absence of sucrose in solution (create a medium similar of syrups). The HPLC was used for the assay, by a validated method for the parabens assay and the statistical analysis of the data is carried out by JMP software. The results show a direct influence of temperature and pH on the level of parabens, while the influence of light remains negligible. The increase in temperature gives a degree of immunity of parabens levels, especially with the extreme values of pH. This study is one of the first studies of forced decomposition of parabens carried out under the various conditions suggested. The results give an idea of the stability profile of the tested parabens and suggest a model of the conditions of conservation and use of these products in different domains and under different conditions.

scholarly journals Hybrid tea-roses under controlled light conditions. I. The effect of the level of irradiance on the growth and development of seedlings.

1978 ◽  
Vol 26 (1) ◽  
pp. 119-127
Author(s):  
D.P. de Vries ◽  
L. Smeets
Keyword(s):  
Light Intensity ◽  
Leaf Area ◽  
Growth And Development ◽  
Day Length ◽  
Light Conditions ◽  
Flower Bud ◽  
Juvenile Period ◽  
Low Light ◽  
Bud Formation ◽  
Flower Bud Abortion

As a basis for breeding cvs adapted to flowering in winter light conditions, the growth of hybrid tea rose seedlings under controlled conditions was studied. Irradiance varied from 4-24 W/m2, day length was 8 h, temperature 21 deg C. Like cvs, the seedlings sometimes aborted the flower bud at low light intensity. With increasing irradiances, the following phenomena were observed: the juvenile period of the seedlings shortened; plants were longer at bud formation, at first flowering and at flower bud abortion; leaf area and the number of petals increased. Leaf number was constant at all irradiances. Flowering seedlings were smaller at bud formation, but taller at actual flowering than blind ones. Blind seedlings had fewer leaves with a smaller area. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Temperature and Light-Quality-Dependent Regulation of Freezing Tolerance in Barley

Plants ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 83 ◽  
Author(s):  
Mohamed Ahres ◽  
Krisztián Gierczik ◽  
Ákos Boldizsár ◽  
Pavel Vítámvás ◽  
Gábor Galiba
Keyword(s):  
Light Intensity ◽  
Target Gene ◽  
Light Quality ◽  
Incident Light ◽  
Gene Expression Pattern ◽  
Frost Tolerance ◽  
Light Conditions ◽  
Incident Light Intensity ◽  
Binding Factor ◽  
R:Fr Ratio

It is established that, besides the cold, incident light also has a crucial role in the cold acclimation process. To elucidate the interaction between these two external hardening factors, barley plantlets were grown under different light conditions with low, normal, and high light intensities at 5 and 15 °C. The expression of the HvCBF14 gene and two well-characterized members of the C-repeat binding factor (CBF)-regulon HvCOR14b and HvDHN5 were studied. In general, the expression level of the studied genes was several fold higher at 5 °C than that at 15 °C independently of the applied light intensity or the spectra. The complementary far-red (FR) illumination induced the expression of HvCBF14 and also its target gene HvCOR14b at both temperatures. However, this supplementation did not affect significantly the expression of HvDHN5. To test the physiological effects of these changes in environmental conditions, freezing tests were also performed. In all the cases, we found that the reduced R:FR ratio increased the frost tolerance of barley at every incident light intensity. These results show that the combined effects of cold, light intensity, and the modification of the R:FR light ratio can greatly influence the gene expression pattern of the plants, which can result in increased plant frost tolerance.

The Fate of Nitrofen in Rape, Redroot Pigweed, and Green Foxtail

Weed Science ◽  
1971 ◽  
Vol 19 (5) ◽  
pp. 555-558 ◽  
Author(s):  
D. Hawton ◽  
E. H. Stobbe
Keyword(s):  
Light Intensity ◽  
Brassica Campestris ◽  
Molecular Size ◽  
Amaranthus Retroflexus ◽  
High Light ◽  
Setaria Viridis ◽  
Light Conditions ◽  
Ether Linkage ◽  
Redroot Pigweed ◽  
Green Foxtail

The fate of 2,4-dichlorophenyl p-nitrophenyl ether (nitrofen) in the foliage of rape (Brassica campestris L. ‘Echo’), redroot pigweed (Amaranthus retroflexus L.), and green foxtail (Setaria viridis (L.) Beauv.) was investigated with the aid of 14C-nitrofen. Only limited amounts of the label were translocated in these species. Plants treated with 14C-nitrofen under high light conditions produced several labelled compounds of different molecular size and chromatographic properties. The time at which these compounds were first detectable depended on light intensity. At least two of these compounds are lipid-nitrofen conjugates or nitrofen polymers and others may be formed by cleavage of nitrofen at the ether linkage.

scholarly journals Interactive Effects of Light and Nitrogen on Pakchoi (Brassica chinensis L.) Growth and Soil Enzyme Activity in an Underground Environment

Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1772
Author(s):  
Songsong Li ◽  
Chao Liu ◽  
Xiao Tan ◽  
Bo Tan ◽  
Yuxin He ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Light Intensity ◽  
Nitrogen Addition ◽  
Soil Enzyme ◽  
Soil Enzyme Activity ◽  
Interactive Effects ◽  
Light Conditions ◽  
Nitrogen Application ◽  
Plant Yield ◽  
Plant Microbe Interaction

Light conditions and nitrogen fertilizer are crucial for plant growth, especially in the underground situations without sunlight and nitrogen deposition. In this paper, the effects of photoperiod (12 h and 16 h lighting time per day), light intensity (200, 300 and 400 μmol m−2 s−1) and nitrogen addition (0, 0.15, 0.3 and 0.45 g N kg−1 soil) on pakchoi growth and specific soil enzyme activity were investigated. The results demonstrated that there were strong interactive effects of light intensity and nitrogen addition on plant yield. The plant yield changed parabolically with increasing nitrogen addition when a light intensity was given between 200 and 300 μmol m−2 s−1, while the yield decreased linearly with increasing nitrogen application under the light intensity of 400 μmol m−2 s−1. The combination of 16 h photoperiod, 300 μmol m−2 s−1 light intensity and 0.3 g N kg−1 soil nitrogen addition was the best for pakchoi growth. The investigation of soil enzyme showed that the activity of urease responded negatively to nitrogen addition, whereas the activity of phosphatase had positive correlation with light intensity but was not affected by nitrogen addition. Our results suggested that the toxic effect of excessive nitrogen was a better explanation for the interactive effects of light and nitrogen than the plant-microbe interaction framework. The critical toxicity level of nitrogen for pakchoi was determined and showed negative correlation with light intensity.

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