scholarly journals Light Intensity Affects the Coloration and Structure of Chimeric Leaves of Ananas comosus var. bracteatus

Phyton ◽  
2022 ◽  
Vol 91 (2) ◽  
pp. 333-348
Author(s):  
Wei Yang ◽  
Yuke Lin ◽  
Yanbin Xue ◽  
Meiqin Mao ◽  
Xuzixing Zhou ◽  
...  
Keyword(s):  
Light Intensity ◽  
Ananas Comosus

scholarly journals Light intensity affects the coloration and structure of chimeric leaves of Ananas comosus var. bracteatus

2020 ◽  
Author(s):  
Wei Yang ◽  
Yuke Lin ◽  
Yanbin Xue ◽  
Meiqin Mao ◽  
Xuzixing Zhou ◽  
...  
Keyword(s):  
Light Intensity ◽  
Prolonged Exposure ◽  
High Irradiance ◽  
Ornamental Plant ◽  
Ananas Comosus ◽  
Light Damage ◽  
Leaf Color ◽  
Mesophyll Cells ◽  
Factors Affecting ◽  
Red Color

AbstractAnanas comosus var. bracteatus is an important tropical ornamental plant because of its green/white chimeric leaves. The accumulation of anthocyanin makes the leaf red especially the white margin. However, the leaves lost red color in summer and winter. Light intensity is one of the most important factors affecting leaf color along the season. In order to understand the effects of light intensity on the growth and coloration of the chimeric leaves, Ananas comosus var. bracteatus was grown under full sunlight, 50% shade and 75% shade for 75 days to evaluate the content of pigments, the color parameters (value L*, a*, b*) and structural histocytology characteristics of chimeric leaves. The results showed that high irradiance was beneficial to keep the chimeric leaves red. However, prolonged exposure to high irradiance caused light damage, some of the leaves wrinkled and even burned. Shading decreased the content of anthocyanin and increased the content of chlorophyll especially in the white margin of the leaves. Numerous chloroplasts were found in the mesophyll cells of the white margin part of chimeric leaves under shading for 75 days. The increase of chlorophyll content resulted in better growth of plants. In order to balance the growth and ornamental value of the leaves, approximately 50% shade is suggested to be the optimum light irradiance condition for Ananas comosus var. bracteatus in summer.

Fine structure of the retina of the giant scallop, Placopecten magellanicus

1984 ◽  
Vol 42 ◽  
pp. 312-313
Author(s):  
C.V.L. Powell
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Light Intensity ◽  
Scanning Electron Microscope ◽  
Eye Development ◽  
Preliminary Observation ◽  
Columnar Epithelium ◽  
Placopecten Magellanicus ◽  
Environmental Light ◽  
Scanning Electron

The overall fine structure of the eye in Placopecten is similar to that of other scallops. The optic tentacle consists of an outer columnar epithelium which is modified into a pigmented iris and a cornea (Fig. 1). This capsule encloses the cellular lens, retina, reflecting argentea and the pigmented tapetum. The retina is divided into two parts (Fig. 2). The distal retina functions in the detection of movement and the proximal retina monitors environmental light intensity. The purpose of the present study is to describe the ultrastructure of the retina as a preliminary observation on eye development. This is also the first known presentation of scanning electron microscope studies of the eye of the scallop.

Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

1988 ◽  
Vol 46 ◽  
pp. 300-301
Author(s):  
C. S. Bricker ◽  
S. R. Barnum ◽  
B. Huang ◽  
J. G. Jaworskl
Keyword(s):  
Fatty Acid ◽  
Light Intensity ◽  
Acid Content ◽  
Fatty Acid Content ◽  
Anabaena Variabilis ◽  
Chloroplast Envelope ◽  
Major Constituent ◽  
Filamentous Cyanobacterium ◽  
Photosynthetic Membrane ◽  
Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

Inter-Method Reliability of Pulse Volume Related Measures Derived Using Finger-Photoplethysmography

2018 ◽  
Vol 32 (4) ◽  
pp. 182-190 ◽  
Author(s):  
Kenta Matsumura ◽  
Koichi Shimizu ◽  
Peter Rolfe ◽  
Masanori Kakimoto ◽  
Takehiro Yamakoshi
Keyword(s):  
Light Intensity ◽  
Adverse Effects ◽  
Light Source ◽  
Direct Current ◽  
Resting State ◽  
Current Component ◽  
Psychophysiological Measures ◽  
Pulse Volume ◽  
Optical Paths ◽  
Sensor Positions

Abstract. Pulse volume (PV) and its related measures, such as modified normalized pulse volume (mNPV), direct-current component (DC), and pulse rate (PR), derived from the finger-photoplethysmogram (FPPG), are useful psychophysiological measures. Although considerable uncertainties exist in finger-photoplethysmography, little is known about the extent of the adverse effects on the measures. In this study, we therefore examined the inter-method reliability of each index across sensor positions and light intensities, which are major disturbance factors of FPPG. From the tips of the index fingers of 12 participants in a resting state, three simultaneous FPPGs having overlapping optical paths were recorded, with their light intensity being changed in three steps. The analysis revealed that the minimum values of three coefficients of Cronbach’s α for ln PV, ln mNPV, ln DC, and PR across positions were .948, .850, .922, and 1.000, respectively, and that those across intensities were .774, .985, .485, and .998, respectively. These findings suggest that ln mNPV and PR can be used for psychophysiological studies irrespective of minor differences in sensor attachment positions and light source intensity, whereas and ln DC can also be used for such studies but under the condition of light intensity being fixed.

Ananas comosus extract mediates uterotonic effect through serotonergic pathway

2017 ◽  
Author(s):  
F Monji ◽  
PG Adaikan ◽  
C Lau Lang ◽  
AM Siddiquee Abrar ◽  
B Said Baharudin ◽  
...  
Keyword(s):  
Ananas Comosus ◽  
Serotonergic Pathway

PELÍCULAS COMESTIBLES ELABORADAS CON PECTINA DE CÁSCARA DE PIÑA (Ananas comosus L.)

2018 ◽  
Vol 11 (11) ◽  
Author(s):  
M. Díaz-Ramírez
Keyword(s):  
Ananas Comosus

Objetivo: Elaborar películas comestibles con la pectina extraída de la cáscara de piña, (Ananas comosus L.) y evaluar características de color, resistencia a la perforación y degradabilidad. Diseño/metodología/aproximación: Las películas comestibles se elaboraron utilizando el método de vaciado en placa (7ml y 10ml). Resultados: Las películas de pectina de cáscara de piña tuvieron valores de luminosidad y resistencia a la perforación menores (entre 42.18 ±0.47 y 31.07 ±0.66; entre 8.87 ±0.82 N y 3.61 ±0.4 N) que las del control (cítricos) (entre 86.0 ±0.26 y 85.46 ±0.99; entre 26.01 ±2.9 N y 18.82 ±1.9 N) pero su degradabilidad (% pérdida de peso) al primer día fue significativamente mayor (P<0.05); al final (7 d) ambos tipos de películas mostraron una degradabilidad similar (99%). Limitaciones del estudio/implicaciones: Se deben mejorar las propiedades físicas y mecánicas de las películas comestibles hechas con pectina extraída de la cáscara de piña. Hallazgos/conclusiones: Este trabajo demostró que las películas a partir de pectina de cáscara de piña son altamente biodegradables y no se descarta su uso y aplicación en alimentos; sin embargo, se requieren más estudios para la optimización de sus características físicas y mecánicas.

Effect of light intensity and water aging on surface hardness of dental resin-composites

2019 ◽  
Vol 64 (11) ◽  
pp. 1007-1014
Author(s):  
Tong XU ◽  
◽  
Jia-Hui ZHANG ◽  
Zhao-Ying LIU ◽  
Xuan LI ◽  
...  
Keyword(s):  
Light Intensity ◽  
Surface Hardness ◽  
Resin Composites ◽  
Dental Resin ◽  
Dental Resin Composites ◽  
Effect Of Light
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