scholarly journals Orb-weaving spiders are fewer but larger and catch more prey in lit bridge panels from a natural artificial light experiment

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8808 ◽  
Author(s):  
Dylan G.E. Gomes
Keyword(s):  
Urban Areas ◽  
Prey Capture ◽  
Trophic Levels ◽  
Artificial Light ◽  
Insect Communities ◽  
Artificial Lighting ◽  
Lighting Conditions ◽  
Insect Trap ◽  
Increased Risk ◽  
Web Building

Artificial light at night is rapidly changing the sensory world. While evidence is accumulating for how insects are affected, it is not clear how this impacts higher trophic levels that feed on insect communities. Spiders are important insect predators that have recently been shown to have increased abundance in urban areas, but have shown mixed responses to artificial light. On a single bridge with alternating artificially lit and unlit sections, I measured changes in the orb-weaving spider Larinioides sclopetarius (Araneidae) web abundance, web-building behavior, prey-capture, and body condition. In artificially lit conditions, spiders caught more prey with smaller webs, and had higher body conditions. However, there were fewer spiders with active webs in those lit areas. This suggests that either spiders were not taking advantage of an ecological insect trap, perhaps due to an increased risk of becoming prey themselves, or were satiated, and thus not as active within these habitats. The results from this natural experiment may have important consequences for both insects and spiders in urban areas under artificial lighting conditions.

Reconstructing Artificial Light in Ancient Greece

2017 ◽  
Author(s):  
Dorina Moullou ◽  
Fragiskos V. Topalis
Keyword(s):  
Experimental Data ◽  
Optical Properties ◽  
Ancient Greece ◽  
Artificial Light ◽  
Light Sources ◽  
Colour Discrimination ◽  
Colour Perception ◽  
Relative Ease ◽  
Artificial Lighting ◽  
Lighting Conditions

This chapter presents an overview of artificial lighting means and their efficiency in the performance of domestic nocturnal activities (except cult practices) in ancient Greece. Through experiments conducted in the Lighting Laboratory of the National Technical University of Athens, the optical properties of exact copies of ancient light sources are investigated. The experimental data are used to assess the sufficiency of light produced by the lighting devices, and to examine the resulting lighting conditions in relation to colour perception and domestic nocturnal activities. The results show that people in antiquity could move around and operate with relative ease at night. Most domestic nocturnal activities could be performed even by the light of a single lamp, provided that it was located relatively nearby. Activities involving colour discrimination, such as weaving, were the most difficult but not impossible to perform. Therefore, artificial light in antiquity could be both effective and economical.

scholarly journals 233 Effects of Photoperiod during Transplant Production under Artificial Lighting Conditions on Floral Development and Bolting of Spinacia oleracea L.

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 482C-482
Author(s):  
Hyeon-Hye Kim ◽  
Changhoo Chun ◽  
Toyoki Kozai ◽  
Junya Fuse
Keyword(s):  
Production Process ◽  
Floral Development ◽  
Spinacia Oleracea ◽  
Stem Elongation ◽  
Value Added ◽  
Short Photoperiod ◽  
Artificial Light ◽  
Artificial Lighting ◽  
Lighting Conditions ◽  
Spinacia Oleracea L

Spinach (Spinacia oleracea L.) was chosen to demonstrate that value-added transplant can be relatively easily produced under artificial light in a closed system. Transplant production under artificial light was divided into three periods, and the photoperiod during each period was varied. It was found that the rate of floral development could be controlled by photoperiod treatments, although floral initiation itself could not be manipulated. Short photoperiod treatments retarded floral development and stem elongation. This occurred even when the transplants were transferred for transplanting to natural conditions with long days and high temperatures. In conclusion, by providing the short photoperiod during the transplant production process, marketable plants with negligible bolting can be produced under natural long-day conditions. Moreover, the production cost per transplant in summer could be reduced by using a combination of natural and artificial lighting during the transplant production process. These results open the possibility to produce value-added transplants of different species under artificial lighting conditions and control their floral development and/or stem elongation for a timely and profitable harvest.

scholarly journals The Potential Use of Photoperiod during Transplant Production under Artificial Lighting Conditions on Floral Development and Bolting, Using Spinach as a Model

HortScience ◽  
2000 ◽  
Vol 35 (1) ◽  
pp. 43-45 ◽  
Author(s):  
Hyeon-Hye Kim ◽  
Changhoo Chun ◽  
Toyoki Kozai ◽  
Junya Fuse
Keyword(s):  
Floral Development ◽  
Spinacia Oleracea ◽  
Stem Elongation ◽  
Artificial Light ◽  
Floral Initiation ◽  
Growth Phases ◽  
Artificial Lighting ◽  
Lighting Conditions ◽  
Long Day ◽  
Potential Use

Spinach (Spinacia oleracea L.) was chosen to demonstrate that the respective vegetative or reproductive conditions of transplants can be controlled in their early stages of development under artificial light in a closed system. Transplant production under artificial light was divided into three growth phases and the photoperiod during each of these phases was varied. The rate of floral development was controlled by photoperiod, but floral initiation itself was not affected. Short photoperiod treatments (8 or 12 hours/day) retarded floral development and stem elongation (bolting). This delay continued even after the transplants were transferred to natural long-day (15.5 hours/day on average) conditions with high temperatures (17 and 37 °C minimum and maximum). We concluded that by using short photoperiods during transplant production, marketable plants with reduced bolting could be produced under natural long-day conditions. In Japan, spinach with this rosetting capacity would be of greater value. Further, this concept opens the possibility of producing better quality transplants of several species under artificial lighting conditions of appropriate length, and thereby controlling their floral development and/or bolting.

Factors that contribute to urban–rural gradients in risk of schizophrenia: Comparing Danish and Western Australian registers

2021 ◽  
pp. 000486742110096
Author(s):  
Oleguer Plana-Ripoll ◽  
Patsy Di Prinzio ◽  
John J McGrath ◽  
Preben B Mortensen ◽  
Vera A Morgan
Keyword(s):  
Confidence Interval ◽  
Western Australia ◽  
Urban Areas ◽  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Hazard Ratio ◽  
Indigenous Status ◽  
Increased Risk ◽  
The Relationship ◽  
Western Australian

Introduction: An association between schizophrenia and urbanicity has long been observed, with studies in many countries, including several from Denmark, reporting that individuals born/raised in densely populated urban settings have an increased risk of developing schizophrenia compared to those born/raised in rural settings. However, these findings have not been replicated in all studies. In particular, a Western Australian study showed a gradient in the opposite direction which disappeared after adjustment for covariates. Given the different findings for Denmark and Western Australia, our aim was to investigate the relationship between schizophrenia and urbanicity in these two regions to determine which factors may be influencing the relationship. Methods: We used population-based cohorts of children born alive between 1980 and 2001 in Western Australia ( N = 428,784) and Denmark ( N = 1,357,874). Children were categorised according to the level of urbanicity of their mother’s residence at time of birth and followed-up through to 30 June 2015. Linkage to State-based registers provided information on schizophrenia diagnosis and a range of covariates. Rates of being diagnosed with schizophrenia for each category of urbanicity were estimated using Cox proportional hazards models adjusted for covariates. Results: During follow-up, 1618 (0.4%) children in Western Australia and 11,875 (0.9%) children in Denmark were diagnosed with schizophrenia. In Western Australia, those born in the most remote areas did not experience lower rates of schizophrenia than those born in the most urban areas (hazard ratio = 1.02 [95% confidence interval: 0.81, 1.29]), unlike their Danish counterparts (hazard ratio = 0.62 [95% confidence interval: 0.58, 0.66]). However, when the Western Australian cohort was restricted to children of non-Aboriginal Indigenous status, results were consistent with Danish findings (hazard ratio = 0.46 [95% confidence interval: 0.29, 0.72]). Discussion: Our study highlights the potential for disadvantaged subgroups to mask the contribution of urban-related risk factors to risk of schizophrenia and the importance of stratified analysis in such cases.

Errors of In Situ Illuminance Measurements

2016 ◽  
Vol 824 ◽  
pp. 676-683
Author(s):  
Michaela Hlásková ◽  
Lenka Gábrová ◽  
František Vajkay
Keyword(s):  
Measurement Errors ◽  
Daily Basis ◽  
Lighting Design ◽  
Public Health Authority ◽  
Construction Work ◽  
Measurement Instruments ◽  
Artificial Lighting ◽  
Lighting Conditions ◽  
Overcast Sky

Lighting conditions in buildings are verified by experts on a daily basis. Such verifications may be done at several phases in various ways. In the field of daylighting, it is common to make an assessment within the pre-design and in-design phases of a construction work throughout calculations, only rarely by measurements. This approach is the opposite of artificial lighting design, which is done within the in-design phase by calculations and is verified by measurements in post-realization phase. The verification of artificial lighting design is required by the building and public health authority otherwise buildings cannot be approved to use. In the field of daylighting, measurements could be performed as well, nevertheless those are often problematic because regulations usually require fulfilments of the daylight factor which can be determined only under CIE overcast sky. Howbeit, both artificial lighting and daylighting measurements are influenced by many errors, e.g. errors of light measurement instruments, measurement conditions, measurement methods and human factor. The paper is focused on this aspect of lighting design, more specifically on the daylighting measurement errors.

scholarly journals Environmental Risk Assessment of Vehicle Exhaust Particles on Aquatic Organisms of Different Trophic Levels

Toxics ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 261
Author(s):  
Konstantin Pikula ◽  
Mariya Tretyakova ◽  
Alexander Zakharenko ◽  
Seyed Ali Johari ◽  
Sergey Ugay ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Sea Urchin ◽  
Urban Areas ◽  
Aquatic Organisms ◽  
Artemia Salina ◽  
Trophic Levels ◽  
Submicron Particles ◽  
Vehicle Exhaust ◽  
Exhaust Particles ◽  
The Difference

Vehicle emission particles (VEPs) represent a significant part of air pollution in urban areas. However, the toxicity of this category of particles in different aquatic organisms is still unexplored. This work aimed to extend the understanding of the toxicity of the vehicle exhaust particles in two species of marine diatomic microalgae, the planktonic crustacean Artemia salina, and the sea urchin Strongylocentrotus intermedius. These aquatic species were applied for the first time in the risk assessment of VEPs. Our results demonstrated that the samples obtained from diesel-powered vehicles completely prevented egg fertilization of the sea urchin S. intermedius and caused pronounced membrane depolarization in the cells of both tested microalgae species at concentrations between 10 and 100 mg/L. The sample with the highest proportion of submicron particles and the highest content of polycyclic aromatic hydrocarbons (PAHs) had the highest growth rate inhibition in both microalgae species and caused high toxicity to the crustacean. The toxicity level of the other samples varied among the species. We can conclude that metal content and the difference in the concentrations of PAHs by itself did not directly reflect the toxic level of VEPs, but the combination of both a high number of submicron particles and high PAH concentrations had the highest toxic effect on all the tested species.

scholarly journals CONTAMINATION BY HEAVY METALS AND ITS CONSEQUENCES: REFLECTIONS

2020 ◽  
Vol 3 (1) ◽  
pp. 101
Author(s):  
Gabrielle Diniz dos Santos ◽  
Gil Dutra Furtado ◽  
Cíntia Cleub Neves Batista
Keyword(s):  
Heavy Metals ◽  
Urban Areas ◽  
Memory Loss ◽  
Trophic Levels ◽  
Low Fertility ◽  
Free Form ◽  
Dissolved Metals ◽  
Physiological Factors ◽  
The Central Nervous System ◽  
Anthropic Influence

Nowadays, the vast majority of aquatic bodies suffer some kind of anthropic influence due to the great expansion of urban areas and consequently industrial areas, with the pollution coming into such environments. One of the types of pollutants present in the environment are heavy metals, which are found naturally in water bodies due to the weathering of rocks and volcanic activities. The present work is of bibliographic nature, based on searches in the bibliography pertinent to the theme. It is possible to state that with anthropic intervention, such metals become common and are found in greater quantities in the environment in a free form. Thus, some of the most common sources of release of heavy metals into the environment are fertilizers, pesticides, coal and oil combustion, vehicular emissions, mining, smelting, refinement and incineration of urban and industrial waste. Thus making contamination of humans with heavy metals more and more common, one of the most common and easy forms of contamination is through food. The absorption of metals by animals can occur in two ways, bioaccumulation and biomagnification. The first occurs through the diffusion or ingestion of the dissolved metals in the water, which occur through the gills or the digestive tract and then lodges in the animals' tissues, so that the organism cannot absorb it, thus obtaining a bioaccumulative character. In the trophic biomagnification or magnification, the concentration of metals in the organism occurs gradually through the trophic levels. The transfer of contaminants through the food chain characterizes such a process that passes from producers to consumers and the longer the chain, the greater the concentration on the final consumer. Therefore, we can emphasize that the concentration and absorption content of such substances are relative and depend on several environmental and physiological factors that vary between species of beings. Metal poisoning can cause serious damage, such as low fertility, decreased immune defenses, reduced growth rate and pathologies that can lead to senescence. Metals can cause different problems in humans, most of which are of a motor nature, as they directly affect the central nervous system (CNS), and can cause memory loss, uncontrolled limb tremors, muscle atrophy, kidney injuries, among others.

scholarly journals The strategy of creating highly productive forms of radish, adapted for cultivation under artificial light conditions

2019 ◽  
Vol 1 (1) ◽  
pp. 29-33 ◽  
Author(s):  
A. A. Kochetov ◽  
N. G. Sinyavina
Keyword(s):  
Small Volume ◽  
Morphological Characteristics ◽  
Intraspecific Diversity ◽  
Artificial Light ◽  
Light Conditions ◽  
Early Maturity ◽  
Artificial Lighting ◽  
First And Second Generation ◽  
Incandescent Lamps ◽  
Different Origin

The strategy of creating new radish forms adapted for cultivation under artificial lighting was developed and implemented. It was based on the original methodology of obtaining transgressive forms of various cultures with a predictable complex of economically valuable properties. Plants were grown in controlled conditions, under incandescent lamps DNAZ-400 (12 hours photoperiod, irradiation of 40-60 W/m2 PAR), in a small volume of the root medium. At the first stage, the intraspecific diversity of radish (26 varieties of different origin) under artificial lighting has been studied. Differences between varieties were determined for the complex of selective-valuable characteristics (early maturity, productivity, morphological characteristics). The most productive varieties are revealed, as well as varieties donors of economically valuable properties that are realized under artificial lighting at a short day and high temperature. Parent pairs have been selected for the subsequent receipt of highly productive transgressive forms using the original breeding methodology. The evaluation of hybrids of the first and second generation showed the presence of heterosis on the mass of the root up to 230% in various combinations of hybridization and revealed promising transgressive forms.

scholarly journals Aberrant Lighting Causes Anxiety-like Behavior in Mice but Curcumin Ameliorates the Symptoms

Animals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2590
Author(s):  
Dhondup Namgyal ◽  
Kumari Chandan ◽  
Sher Ali ◽  
Ajaz Ahmad ◽  
Maha J. Hashim ◽  
...  
Keyword(s):  
Body Weight ◽  
Research Field ◽  
The Body ◽  
Laboratory Animals ◽  
Artificial Lighting ◽  
Lighting Conditions ◽  
Daily Food ◽  
Significant Difference ◽  
Negative Effect ◽  
Lighting Systems

In the modern research field, laboratory animals are constantly kept under artificial lighting conditions. However, recent studies have shown the effect of artificial light on animal behavior and metabolism. In the present study on mice, following three weeks of housing in dim light at night (dLAN; 5lux) and complete darkness (DD; 0lux), we monitored the effect on body weight, daily food intake, anxiety-like behavior by employing the open field test, and expression of the period (PER1) gene. We also studied the effect of oral administration of different concentrations of curcumin (50, 100, and 150 mg/kg) for three weeks in the same mice and monitored these parameters. The exposure to dLAN had significantly increased the anxiety-like behavior and body weight possibly through the altered metabolism in mice, whereas exposure to DD caused increased anxiety but no significant difference in weight gain. Moreover, the expression of the PER1 gene involved in sleep was also found to be decreased in the aberrant light conditions (dLAN and DD). Although the treatment of curcumin had no effect on body weight, it ameliorated the anxiety-like behavior possibly by modulating the expression of the PER1 gene. Thus, alteration in the light/dark cycle had a negative effect on laboratory animals on the body weight and emotions of animals. The present study identifies the risk factors associated with artificial lighting systems on the behavior of laboratory animals and the ameliorative effects of curcumin, with a focus on anxiety-like behavior.

scholarly journals Toxoplasma antibody and stool parasites in public school children, Rolândia, Paraná, Brazil

2002 ◽  
Vol 35 (3) ◽  
pp. 215-219 ◽  
Author(s):  
Nilson Giraldi ◽  
Odilon Vidotto ◽  
Italmar Teodorico Navarro ◽  
João Luis Garcia ◽  
Liza Ogawa ◽  
...  
Keyword(s):  
Elementary Schools ◽  
Public School ◽  
Toxoplasma Gondii ◽  
School Children ◽  
Urban Areas ◽  
Ocular Toxoplasmosis ◽  
Rural And Urban Areas ◽  
Rural And Urban ◽  
Increased Risk ◽  
Amsler Grid

The occurrence of toxoplasmosis and enteroparasitosis was studied in 434 children from elementary schools in the rural and urban areas of Rolândia, Paraná State, Brazil. Sera and fecal samples from all the students were submitted to IFA for Toxoplasma gondii and coproparasitological tests, respectively. The children were tested by Amsler grid and 72 of them were examined for the presence of lesions compatible with ocular toxoplasmosis. Some variables were tested but none showed increased risk for toxoplasmosis. The distribution according to sex and age and also same other variables are presented and discussed. Correlations between Amsler's grid test, toxoplama RIFI, occurrence of eyes lesions and enteroparasitosis are also considered.

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