LIGHT ONSET AND TERMINATION AS REINFORCERS FOR RATS LIVING UNDER NORMAL LIGHT CONDITIONS

AbstractNauclea diderrichii(De Wild and Th. Dür.) (common name Kusia and trade name, Opepe) is an evergreen tree found throughout the tropical rainforests of West Africa. It is heavily exploited for its timber and listed as vulnerable on the IUCN Red List of Threatened Species. The shoot borerOrygmophora mediofoveataHamps, which attacks the nursery stage, has hampered attempts to establishN. diderrichiiplantations in Ghana. This study examined the potential of four insecticides to protectN. diderrichiiseedlings fromO. mediofoveataattack and damage. Four insecticides–Pyrinex (chlorpyrifos), Dursban (chlorpyrifos), Cerox (dimethoate) and Golan (acetamiprid)–were applied to four-month-oldN. diderrichiiseedlings growing in full sunlight and under shade (80% of normal light), to evaluate their effects on incidence of attack, survival, severity of damage and growth. Insecticide treatment and light conditions had variable effects on the damage and growth of the seedlings after six months of evaluation. Seedling survival was not significantly influenced by the insecticide treatment. Percent survival of insecticide-treated seedlings did not differ significantly from that of control seedlings in full sun; however, under shade survival of treated seedlings was significantly higher than control seedlings. Nonetheless, control seedlings in full sun had higher survival (92.5%) than those under shade (62.5%). Insecticide-treated seedlings in full sun had lower incidence of shoot borer attack than those under shade. In full sun, dieback incidence following shoot borer attack was significantly lower for insecticide-treated than control seedlings. Growth in height and girth of seedlings was influenced positively by both insecticide and light, with girth especially being significantly lower under shade conditions. Currently,N. diderrichiiseedlings are typically raised under shade; however, this study shows that raising seedlings in full sun with insecticide application could result in faster and better growth.

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Limits of cross-modal plasticity? Short-term visual deprivation does not enhance cardiac interoception, thermosensation, or tactile spatial acuity

10.31234/osf.io/g94j8 ◽

2021 ◽

Author(s):

Dominika Radziun ◽

Laura Crucianelli ◽

H. Henrik Ehrsson

Keyword(s):

Healthy Volunteers ◽

Washout Period ◽

Visual Deprivation ◽

Control Group ◽

Light Conditions ◽

Complete Darkness ◽

Short Term ◽

Experimental Conditions ◽

Normal Light ◽

Experimental Group

In the present study, we investigated the effect of short-term visual deprivation on discriminative touch, cardiac interoception, and thermosensation by asking 64 healthy volunteers to perform four behavioral tasks. The experimental group contained 32 subjects who were blindfolded and kept in complete darkness for 110 minutes, while the control group consisted of 32 volunteers who were not blindfolded but were otherwise kept under identical experimental conditions. Both groups performed the required tasks three times: before and directly after deprivation (or control) and after an additional washout period of 40 minutes, in which all participants were exposed to normal light conditions. Our results showed that short-term visual deprivation had no effect on any of the senses tested. This finding suggests that short-term visual deprivation does not modulate basic bodily senses and extends this principle beyond tactile processing to the interoceptive modalities of cardiac and thermal sensations.

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The effect of light and darkness on the production of cercariae of Schistosoma haematobium from Bulinus globosus

Journal of Helminthology ◽

10.1017/s0022149x00010191 ◽

1987 ◽

Vol 61 (4) ◽

pp. 291-296 ◽

Cited By ~ 12

Author(s):

K. M. Raymond ◽

A. J. Probert

Keyword(s):

Schistosoma Haematobium ◽

Continuous Illumination ◽

Light Conditions ◽

Dark Treatment ◽

Bulinus Globosus ◽

Normal Light ◽

Peak Emission ◽

Evening Peak ◽

Second Peak ◽

Effect Of Light

ABSTRACTThe cercariae of Schistosoma haematobium showed a diurnal periodicity of emergence from Bulinus globosus in a twelve hour light/dark cycle. Peak emission occurred at 11.00 hrs with a smaller peak at 20.00 hrs, following the start of the period of darkness. In continuous illumination this second peak was not seen, indicating that only the morning peak is circadian in origin. The evening peak occurs in response to dark treatment and can be produced by periods of darkness ranging from eight seconds to one hour. The longer the period of dark treatment the longer the rise in output is maintained on return to light conditions. Subjection of snails to periods of dark treatment during the normal light period caused a reduction in the evening peak with the largest effect seen following the longest period of darkness. An increased output of cercariae was seen following fifteen minutes exposure to a range of light intensities, the largest increase occurring at 10 000 and 7000 lux and complete darkness. The rapidity of this reaction to variations in light intensity suggests that the cercariae of S. haematobium are showing emergence in response to shadows.

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Five new species of Dichaetomyia from the Malagasy Subregion (Diptera: Muscidae)

Historia naturalis bulgarica ◽

10.48027/hnb.42.092 ◽

2021 ◽

Vol 42 (9) ◽

pp. 65-78

Author(s):

Eberhard Zielke

Keyword(s):

New Species ◽

The Body ◽

Light Conditions ◽

Body Colour ◽

Normal Light

Five new species of the genus Dichaetomyia are described from Madagascar. Two species, Dichaetomyia analama sp. n. and D. necoa sp. n. belong to the subgenus Panaga. Three other species, D. amboha sp. n., D. blackia sp. n. and D. tantelya sp. n. are members of the subgenus Dichaetomyia. The body colour in normal light conditions of the five species is predominantly yellowish or grey to dark brown or blackish like most of the Afrotropical species of Dichaetomyia.

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Auto-Exposure Algorithm Based on Luminance Histogram and Region Segmentation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.543-547.2278 ◽

2014 ◽

Vol 543-547 ◽

pp. 2278-2282 ◽

Cited By ~ 2

Author(s):

Zhi Hui Guo ◽

Yuan Bao Gu ◽

Hong Tao Yao

Keyword(s):

Gain Control ◽

Light Conditions ◽

Region Segmentation ◽

Average Brightness ◽

Lighting Conditions ◽

Average Luminance ◽

Front Lighting ◽

Reference Target ◽

Normal Light ◽

Partition Method

This paper proposed an automatic exposure algorithm based on luminance histogram and region segmentation. The method ensures well exposure to the main object under the backlighting or excessive front-lighting conditions, and uses the characteristics of the luminance histogram to judge the scene condition. According to the luminance histogram, if the image under normal light conditions, the method compares the average luminance value of the image with the corresponding reference target brightness value to adjust exposure compensation. If the image under special conditions, the average brightness value will be calculated using fixed-partition method and exposure compensation will be adjusted. The paper combines auto-exposure and auto-gain control to adjust the exposure compensation. As it turns out, this method in a variety of light conditions can achieve well exposure.

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Sustainable and invisible anti-counterfeiting inks based on waterborne polyurethane and upconversion nanoparticles for leather products

Journal of Leather Science and Engineering ◽

10.1186/s42825-021-00076-x ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Jun Xiang ◽

Jianxun Lin ◽

Zhonghui Wang ◽

Shenglin Zhou ◽

Zhenya Wang ◽

...

Keyword(s):

Waterborne Polyurethane ◽

Economic Loss ◽

Upconversion Nanoparticles ◽

Light Conditions ◽

Voc Emissions ◽

Water Dispersible ◽

Volatile Organic ◽

Strong Adhesion ◽

Normal Light

Abstract Counterfeit leather products infringe the intellectual property rights of the business, cause enormous economic loss, and negatively influence the business enthusiasm for innovation. However, traditional anti-counterfeiting materials for leather products suffer from complicated fabrication procedures, photobleaching, and high volatile organic compound (VOC) emissions. Here, a sustainable and invisible anti-counterfeiting ink composed of waterborne polyurethane and water-dispersible lanthanide-doped upconversion nanoparticles (UCNPs) featuring ease of preparation, high photostability, non-toxicity, low VOC emissions, and strong adhesion strength for leather products is designed and synthesized. After decorating on the surface of leather products, the obtained patterns are invisible under normal light conditions. Upon irradiation at 808 nm, the invisible patterns can be observed by naked eyes due to the visible light emitted by 808 nm excited UCNPs. Our approach described here opens a new pathway to realize the long-term, stable anti-counterfeiting function of leather products. Graphical Abstract

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Constant darkness conditions modulate the effects of melatonin and luzindole on the antioxidant enzyme activities and levels of retinol and α-tocopherol in rats

Biological Communications ◽

10.21638/spbu03.2019.305 ◽

2019 ◽

Vol 64 (3) ◽

Author(s):

Svetlana Kalinina ◽

Viktor Ilyukha ◽

Evgeniy Khizhkin ◽

Irina Baishnikova ◽

Ekaterina Antonova ◽

...

Keyword(s):

Superoxide Dismutase ◽

Wistar Rats ◽

Constant Darkness ◽

Antioxidant Enzyme Activities ◽

Light Conditions ◽

Melatonin Receptor ◽

Sod Activity ◽

Male Wistar Rats ◽

Liver And Kidney ◽

Normal Light

This study was conducted to evaluate the effects of both exogenous melatonin and melatonin receptor antagonist luzindole on the activities of antioxidant enzymes (AOE) (superoxide dismutase, SOD; catalase, CAT) and the level of low-molecular antioxidant vitamins (retinol, α-tocopherol) in male Wistar rats kept in normal light conditions (LD 12:12) or constant darkness (DD). In LD, while melatonin had no influence on the studied antioxidants, luzindole caused an increase in retinol and a decrease in α-tocopherol contents in the liver compared to the control. In DD, with no influence on AOE activities, both drugs exerted similar effects on the liver retinol and kidney α-tocopherol contents, increasing them in comparison with control. Exposing the animals to DD induced an increase in kidney SOD activity and in liver retinol content. Moreover, DD-mel rats had higher SOD activity in the liver and kidney and a higher retinol level in the liver compared to LD-mel ones; DD-luz rats had a higher liver retinol content compared to LD-luz ones. Liver retinol level seems to be the most sensitive to influence of DD, melatonin and luzindole; the data are probably connected with the involvement of vitamin A in the regulation of circadian rhythms.

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Evaluation of CBSX Proteins as Regulators of the Chloroplast Thioredoxin System

Frontiers in Plant Science ◽

10.3389/fpls.2021.530376 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ryota Murai ◽

Yuki Okegawa ◽

Nozomi Sato ◽

Ken Motohashi

Keyword(s):

Redox Regulation ◽

Light Conditions ◽

Wild Type ◽

Target Proteins ◽

Thioredoxin System ◽

Biochemical Studies ◽

Metabolic Reactions ◽

Normal Light

The chloroplast-localized cystathionine β-synthase X (CBSX) proteins CBSX1 and CBSX2 have been proposed as modulators of thioredoxins (Trxs). In this study, the contribution of CBSX proteins to the redox regulation of thiol enzymes in the chloroplast Trx system was evaluated both in vitro and in vivo. The in vitro biochemical studies evaluated whether CBSX proteins alter the specificities of classical chloroplastic Trx f and Trx m for their target proteins. However, addition of CBSX proteins did not alter the specificities of Trx f and Trx m for disulfide bond reduction of the photosynthesis-related major thiol enzymes, FBPase, SBPase, and NADP-MDH. In vivo analysis showed that CBSX-deficient mutants grew similarly to wild type plants under continuous normal light conditions and that CBSX deficiency did not affect photo-reduction of photosynthesis-related thiol enzymes by Trx system at several light intensities. Although CBSX proteins have been suggested as modulators in the chloroplast Trx system, our results did not support this model, at least in the cases of FBPase, SBPase, and NADP-MDH in leaves. However, fresh weights of the cbsx2 mutants were decreased under short day. Since Trxs regulate many proteins participating in various metabolic reactions in the chloroplast, CBSX proteins may function to regulate other chloroplast Trx target proteins, or serve as modulators in non-photosynthetic plastids of flowers. As a next stage, further investigations are required to understand the modulation of Trx-dependent redox regulation by plastidal CBSX proteins.

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