Efficiency of seeds' germination in pre-sowing irradiation by UV- light of different spectral composition

The amount and spectral composition of light changes considerably during the day, with dawn and dusk being the most crucial moments when light is within the mesopic range and short wavelength enriched. It was recently shown that animals use both cues to adjust their internal circadian clock, thereby their behavior and physiology, with the solar cycle. The role of blue light in circadian processes and neuronal responses is well established, however, an unanswered question remains: how do changes in the spectral composition of light (short wavelengths blocking) influence neuronal activity? In this study we addressed this question by performing electrophysiological recordings in image (dorsal lateral geniculate nucleus; dLGN) and non-image (the olivary pretectal nucleus; OPN, the suprachiasmatic nucleus; SCN) visual structures to determine neuronal responses to spectrally varied light stimuli. We found that removing short-wavelength from the polychromatic light (cut off at 525 nm) attenuates the most transient ON and sustained cells in the dLGN and OPN, respectively. Moreover, we compared the ability of different types of sustained OPN neurons (either changing or not their response profile to filtered polychromatic light) to irradiance coding, and show that both groups achieve it with equal efficacy. On the other hand, even very dim monochromatic UV light (360 nm; log 9.95 photons/cm2/s) evokes neuronal responses in the dLGN and SCN. To our knowledge, this is the first electrophysiological experiment supporting previous behavioral findings showing visual and circadian functions disruptions under short wavelength blocking environment. The current results confirm that neuronal activity in response to polychromatic light in retinorecipient structures is affected by removing short wavelengths, however, with type and structure – specific action. Moreover, they show that rats are sensitive to even very dim UV light.

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Effects of Continuous Lighting and Light Spectral Composition on Photosynthesis and Related Processes of Greenhousegrown Tomato and Pepper Plants

HortScience ◽

10.21273/hortsci.30.4.778e ◽

1995 ◽

Vol 30 (4) ◽

pp. 778E-778

Author(s):

Dominique-André Demers ◽

Sylvain Dubé ◽

Serge Yelle ◽

André Gosselin

Keyword(s):

Uv Light ◽

Starch Content ◽

Spectral Composition ◽

Continuous Light ◽

Sucrose Phosphate Synthase ◽

Growth And Yield ◽

Carotenoid Content ◽

Negative Effects ◽

Tomato Plants ◽

Pepper Plants

Growing tomato and pepper plants under continuous light causes negative effects such as leaf chlorosis and deformities, and decreased growth and yield. Such effects are more pronounced on tomato plants. Our general objectives are to identify the physiological process(es) responsible for these negative effects and to explain the difference in sensitivity of tomato and pepper plants to continuous light. The specific objective of this experiment was to determine the effects of continuous light and light spectral composition on photosynthesis and related processes of tomato and pepper plants. Tomato and pepper plants were place on 7 June 1994 in growth chambers under photoperiod treatments of 12 h [high-pressure sodium (HPS) lamps], 24 h (HPS lamps), and 24 h [metal halide (MH) lamps]. For all treatments, FPP was 350 μmol·m–2·s–1, temperatures were 21C (day) and 17C (night), and RH was 70%. Every 2 weeks (7 June until 2 Aug.), tomato and pepper leaf samples were harvested and frozen in liquid nitrogen for subsequent measurements of starch content (Robinson et al, 1988, Plant Physiol.), sucrose phosphate synthase activities (Dali et al., 1992, Plant Physiol.) and chlorophyll and carotenoid content (determination on HPLC). A system that measured gas exchange and chlorophyll fluorescence of fresh leaf samples was used to determine the photosynthetic rate and quantum yield of CO2 fixation and electron transport. Development of the negative effects of continuous light on plants was monitored. Light spectral composition of the two types of lamps was measured using a spectroradiometer. Results show that, under continuous light, pepper plants were less-efficient than tomato plants in using light for CO2 fixation, but were more efficient in dissipating the extra energy received. This may explain why pepper plants are less sensitive to continuous light than tomato plants. MH lamps caused more-severe chloroses on tomato leaves than HPS plants. We believe that the higher proportion of UV-light provided by MH lamps may be related to this effect. Detailed results will be presented.

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Electron microscopy of keratinocytes cultured on a collagen substrate used as an allograft for the treatment of chronic wounds

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130158 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1104-1105

Author(s):

Debby A. Jennings ◽

Michael J. Morykwas ◽

Louis C. Argenta

Keyword(s):

Electron Microscopy ◽

Cell Suspension ◽

Single Cell ◽

Chronic Wounds ◽

Mechanical Stability ◽

Uv Light ◽

Type I ◽

Single Cell Suspension ◽

Collagen Substrate ◽

Dermal Collagen

Grafts of cultured allogenic or autogenic keratlnocytes have proven to be an effective treatment of chronic wounds and burns. This study utilized a collagen substrate for keratinocyte and fibroblast attachment. The substrate provided mechanical stability and augmented graft manipulation onto the wound bed. Graft integrity was confirmed by light and transmission electron microscopy.Bovine Type I dermal collagen sheets (100 μm thick) were crosslinked with 254 nm UV light (13.5 Joules/cm2) to improve mechanical properties and reduce degradation. A single cell suspension of third passage neonatal foreskin fibroblasts were plated onto the collagen. Five days later, a single cell suspension of first passage neonatal foreskin keratinocytes were plated on the opposite side of the collagen. The grafts were cultured for one month.The grafts were fixed in phosphate buffered 4% formaldehyde/1% glutaraldehyde for 24 hours. Graft pieces were then washed in 0.13 M phosphate buffer, post-fixed in 1% osmium tetroxide, dehydrated, and embedded in Polybed 812.

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A photoelectron microscope study of surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152021 ◽

1989 ◽

Vol 47 ◽

pp. 10-11

Author(s):

W. Engel ◽

M. Kordesch ◽

A. M. Bradshaw ◽

E. Zeitler

Keyword(s):

Electron Microscopy ◽

High Pressure ◽

Field Strength ◽

Uv Light ◽

Physical Property ◽

Photon Flux ◽

Mercury Lamp ◽

Object Surface ◽

The Sixties ◽

Physical Features

Photoelectron microscopy is as old as electron microscopy itself. Electrons liberated from the object surface by photons are utilized to form an image that is a map of the object's emissivity. This physical property is a function of many parameters, some depending on the physical features of the objects and others on the conditions of the instrument rendering the image.The electron-optical situation is tricky, since the lateral resolution increases with the electric field strength at the object's surface. This, in turn, leads to small distances between the electrodes, restricting the photon flux that should be high for the sake of resolution.The electron-optical development came to fruition in the sixties. Figure 1a shows a typical photoelectron image of a polycrystalline tantalum sample irradiated by the UV light of a high-pressure mercury lamp.

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Immunolabelling of glomerular deposits in kidney biopsies routinely fixed in glutaraldehyde

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156535 ◽

1989 ◽

Vol 47 ◽

pp. 910-911

Author(s):

Ś Lhoták ◽

I. Alexopoulou ◽

G. T. Simon

Keyword(s):

Uv Light ◽

Kidney Diseases ◽

Light Chains ◽

Microscopical Level ◽

Accurate Identification ◽

Light Microscopical Level ◽

Dense Deposits ◽

Cacodylate Buffer ◽

Glomerular Deposits ◽

Prognostic Importance

Various kidney diseases are characterized by the presence of dense deposits in the glomeruli. The type(s) of immunoglobulins (Igs) present in the dense deposits are characteristic of the disease. The accurate Identification of the deposits is therefore of utmost diagnostic and prognostic importance. Immunofluorescence (IF) used routinely at the light microscopical level is unable to detect and characterize small deposits found in early stages of glomerulonephritis. Although conventional TEM is able to localize such deposits, it is not capable of determining their nature. It was therefore attempted to immunolabel at EM level IgG, IgA IgM, C3, fibrinogen and kappa and lambda Ig light chains commonly found in glomerular deposits on routinely fixed ( 2% glutaraldehyde (GA) in 0.1M cacodylate buffer) kidney biopsies.The unosmicated tissue was embedded in LR White resin polymerized by UV light at -10°C. A postembedding immunogold technique was employed

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Amplitude Distributions of Cochlear Microphonic Response to an Acoustic Sinusoid in Noise

Journal of Speech and Hearing Research ◽

10.1044/jshr.1101.63 ◽

1968 ◽

Vol 11 (1) ◽

pp. 63-76

Author(s):

Donald C. Teas ◽

Gretchen B. Henry

Keyword(s):

Small Amplitude ◽

Basilar Membrane ◽

Spectral Composition ◽

Pass Band ◽

Cochlear Microphonic ◽

Filter Output ◽

Electronic Filter ◽

Low Pass ◽

Band Pass ◽

Instantaneous Voltage

The distributions of instantaneous voltage amplitudes in the cochlear microphonic response recorded from a small segment along the basilar membrane are described by computing amplitude histograms. Comparisons are made between the distributions for noise and for those after the addition to the noise of successively stronger sinusoids. The amplitudes of the cochlear microphonic response to 5000 Hz low-pass noise are normally distributed in both Turn I and Turn III of the guinea pig’s cochlea. The spectral composition of the microphonic from Turn I and from Turn III resembles the output of band-pass filters set at about 4000 Hz, and about 500 Hz, respectively. The normal distribution of cochlear microphonic amplitudes for noise is systematically altered by increasing the strength of the added sinusoid. A decrease of three percent in the number of small amplitude events (±1 standard deviation) in the cochlear microphonic from Turn III is seen when the rms voltage of a 500 Hz sinusoid is at −18 dB re the rms voltage of the noise (at the earphone). When the rms of the sinusoid and noise are equal, the decrease in small voltages is about 25%, but there is also an increase in the number of large voltage amplitudes. Histograms were also computed for the output of an electronic filter with a pass-band similar to Turn III of the cochlea. Strong 500 Hz sinusoids showed a greater proportion of large amplitudes in the filter output than in CM III . The data are interpreted in terms of an anatomical substrate.

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Sorbitol enhances the physicochemical stability of B12 vitamers

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000578 ◽

2020 ◽

Vol 90 (5-6) ◽

pp. 439-447 ◽

Cited By ~ 1

Author(s):

Andrew Hadinata Lie ◽

Maria V Chandra-Hioe ◽

Jayashree Arcot

Keyword(s):

Ascorbic Acid ◽

Uv Light ◽

Heat Exposure ◽

Water Soluble ◽

Uv Exposure ◽

Physicochemical Stability ◽

Before And After ◽

The Stability

Abstract. The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%–26% and 48%–76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.

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Effect of GA3 and KNO3 treatments on improving Nepeta crispa seeds germination

Planta Medica ◽

10.1055/s-0031-1282325 ◽

2011 ◽

Vol 77 (12) ◽

Author(s):

P Habibi ◽

K Piri ◽

J Salari ◽

H Hajalizadeh

Keyword(s):

Seeds Germination

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4 Pattern Recognition for Healing Burns to Compute Evidence: Space Syntax and Machine Learning Analysis of Burns Center Karachi

Sir Syed Research Journal of Engineering & Technology ◽

10.33317/ssurj.v1i1.64 ◽

2013 ◽

Vol 1 (1) ◽

pp. 13

Author(s):

Javaria Manzoor Shaikh ◽

JaeSeung Park

Keyword(s):

Pattern Recognition ◽

Prediction Models ◽

Uv Light ◽

Healing Process ◽

Space Syntax ◽

Depth Map ◽

Routine Tasks ◽

Hyper Plane ◽

First Time ◽

Learning Analysis

Usually elongated hospitalization is experienced byBurn patients, and the precise forecast of the placement of patientaccording to the healing acceleration has significant consequenceon healthcare supply administration. Substantial amount ofevidence suggest that sun light is essential to burns healing andcould be exceptionally beneficial for burned patients andworkforce in healthcare building. Satisfactory UV sunlight isfundamental for a calculated amount of burn to heal; this delicaterather complex matrix is achieved by applying patternclassification for the first time on the space syntax map of the floorplan and Browder chart of the burned patient. On the basis of thedata determined from this specific healthcare learning technique,nurse can decide the location of the patient on the floor plan, hencepatient safety first is the priority in the routine tasks by staff inhealthcare settings. Whereas insufficient UV light and vitamin Dcan retard healing process, hence this experiment focuses onmachine learning design in which pattern recognition andtechnology supports patient safety as our primary goal. In thisexperiment we lowered the adverse events from 2012- 2013, andnearly missed errors and prevented medical deaths up to 50%lower, as compared to the data of 2005- 2012 before this techniquewas incorporated.In this research paper, three distinctive phases of clinicalsituations are considered—primarily: admission, secondly: acute,and tertiary: post-treatment according to the burn pattern andhealing rate—and be validated by capable AI- origin forecastingtechniques to hypothesis placement prediction models for eachclinical stage with varying percentage of burn i.e. superficialwound, partial thickness or full thickness deep burn. Conclusivelywe proved that the depth of burn is directly proportionate to thedepth of patient’s placement in terms of window distance. Ourfindings support the hypothesis that the windowed wall is mosthealing wall, here fundamental suggestion is support vectormachines: which is most advantageous hyper plane for linearlydivisible patterns for the burns depth as well as the depth map isused.

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