scholarly journals Bumblebee electric charge stimulates floral volatile emissions in Petunia integrifolia but not in Antirrhinum majus

2021 ◽  
Vol 108 (5) ◽  
Author(s):  
Clara Montgomery ◽  
Jozsef Vuts ◽  
Christine M. Woodcock ◽  
David M. Withall ◽  
Michael A. Birkett ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Electric Charge ◽  
Flowering Plants ◽  
Antirrhinum Majus ◽  
Volatile Emissions ◽  
Flying Insects ◽  
Floral Volatile ◽  
Electrically Charged ◽  
Sensory Process ◽  
Petunia Integrifolia

AbstractThe timing of volatile organic compound (VOC) emission by flowering plants often coincides with pollinator foraging activity. Volatile emission is often considered to be paced by environmental variables, such as light intensity, and/or by circadian rhythmicity. The question arises as to what extent pollinators themselves provide information about their presence, in keeping with their long co-evolution with flowering plants. Bumblebees are electrically charged and provide electrical stimulation when visiting plants, as measured via the depolarisation of electric potential in the stem of flowers. Here we test the hypothesis that the electric charge of foraging bumblebees increases the floral volatile emissions of bee pollinated plants. We investigate the change in VOC emissions of two bee-pollinated plants (Petunia integrifolia and Antirrhinum majus) exposed to the electric charge typical of foraging bumblebees. P. integrifolia slightly increases its emissions of a behaviorally and physiologically active compound in response to visits by foraging bumblebees, presenting on average 121 pC of electric charge. We show that for P. integrifolia, strong electrical stimulation (600–700 pC) promotes increased volatile emissions, but this is not found when using weaker electrical charges more representative of flying pollinators (100 pC). Floral volatile emissions of A. majus were not affected by either strong (600–700 pC) or weak electric charges (100 pC). This study opens a new area of research whereby the electrical charge of flying insects may provide information to plants on the presence and phenology of their pollinators. As a form of electroreception, this sensory process would bear adaptive value, enabling plants to better ensure that their attractive chemical messages are released when a potential recipient is present.

A Self-Sensing Method for IPMC Actuator

2008 ◽  
Vol 56 ◽  
pp. 111-115 ◽  
Author(s):  
Byung Geun Ko ◽  
Hyok Chon Kwon ◽  
Song Jun Lee
Keyword(s):  
Electric Charge ◽  
Position Control ◽  
Conductive Polymer ◽  
Metal Composite ◽  
Position Information ◽  
The Status ◽  
Polymer Metal ◽  
Accurate Position ◽  
Novel Method ◽  
Electrically Charged

This paper describes a novel method of self-sensing Ion-conductive Polymer Metal Composite (IPMC) actuator. Unlike the previous self-sensing technique, the proposed principle is based on the electric charge of the IPMC itself, which is correlated with its curvature. At the normal state, IPMC is electrically charged, and the amount varies according to the status of IPMC. While it is operated as an actuator, it also gives position information in the form of the electric charge amount, which is utilized for fast and accurate position control. In order to get the bending status of the actuator, the instantaneous voltage of IPMC is measured during the open state for input signal. The uncomplicated system is constructed to verify if the developed method is effective for the selfsensing actuator and evaluated by the experimental basis. The way to actuate the IPMC with selfsensing is a supplying discrete signal as an input, and it is also evaluated experimentally. This research also represents relatively simple structure for both actuation and sensing, which is very important factor to be implemented as a controller circuit for various applications.

scholarly journals High Voltage Electric Fields Have Potential to Create New Physical Pest Control Systems

Insects ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 447 ◽  
Author(s):  
Shin-ichi Kusakari ◽  
Kiyotsugu Okada ◽  
Manabu Shibao ◽  
Hideyoshi Toyoda
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Pest Control ◽  
Electric Charge ◽  
High Voltage ◽  
Arc Discharge ◽  
Control Strategies ◽  
Control Measures ◽  
Flying Insects ◽  
Electrostatic Phenomena

An electric field is the space surrounding an electric charge, within which it is capable of exerting a perceptible force on another electric charge. Especially under high voltage, electric fields induce various electrostatic phenomena, some of which could be utilized to provide remarkable pest control measures. The main focus of the present study was to introduce an attractive force generated by a surface charge on an insulated electrified conductor, which was successfully used to construct an electric field screen that prevented airborne nuisances (spores, flying insects, pollen, and fine smoke) from entering the interiors of various facilities. Another focus was the disinclination of insects to enter the electric field, thus, giving the electric field screen the ability to repel insects. Charges accumulated on the surfaces of non-insulated conductors are mobile through discharge, based on their potential difference. Such arc discharge was strong enough to destroy insects that were exposed to it. Some precedent illustrative examples are cited to explain the principles of attraction, dielectrophoretic movement of spores, and discharge-mediated positive electrification of insects, and to discuss how electric fields are generated and used in electric field-based pest control strategies.

scholarly journals Detergent solubilization of phospholipid vesicle. Effect of electric charge

1990 ◽  
Vol 270 (2) ◽  
pp. 305-308 ◽  
Author(s):  
M A Urbaneja ◽  
A Alonso ◽  
J M Gonzalez-Mañas ◽  
F M Goñi ◽  
M A Partearroyo ◽  
...  
Keyword(s):  
Electric Charge ◽  
Mixed Micelles ◽  
Hydrophobic Interactions ◽  
Phospholipid Vesicle ◽  
Detergent Concentration ◽  
Alkyl Sulphate ◽  
Detergent Solubilization ◽  
Dicetyl Phosphate ◽  
Electrically Charged ◽  
Pyridinium Compounds

In order to explore the effect of electric charge on detergent solubilization of phospholipid bilayers, the interaction of nine electrically charged surfactants with neutral or electrically charged liposomes has been examined. The detergents belonged to the alkyl pyridinium, alkyl trimethylammonium or alkyl sulphate families. Large unilamellar liposomes formed by egg phosphatidylcholine plus or minus stearylamine or dicetyl phosphate were used. Solubilization was assessed as a decrease in light-scattering of the liposome suspensions. The results suggest that electrostatic forces do not play a significant role in the formation of mixed micelles and that hydrophobic interactions are by far the main forces involved in solubilization. In addition, from the study of thirty different liposome-surfactant systems, we have derived a series of empirical rules that may be useful in predicting the behaviour of untested surfactants: (i) the detergent concentration producing the onset of solubilization (Don) decreases as the alkyl chain length increases; the decrease follows a semi-logarithmic pattern in the case of alkyl pyridinium compounds; (ii) for surfactants with critical micellar concentrations (cmc) less than 6 x 10(-3) M, Don. is independent of the nature of the detergent and the bilayer composition; for detergents having cmc greater than 6 x 10(-3) M, Don. increases linearly with the cmc; and (iii) Don. varies linearly with the surfactant concentration that produces maximum solubilization.

scholarly journals Electrically-charged black holes and the Blandford-Znajek mechanism

2021 ◽  
Author(s):  
Serguei S Komissarov
Keyword(s):  
Magnetic Field ◽  
Black Holes ◽  
Black Hole ◽  
Electric Charge ◽  
Meissner Effect ◽  
Charged Black Holes ◽  
Field Lines ◽  
The One ◽  
Electrically Charged ◽  
The Magnetic Field

Abstract Recently, it was claimed by King & Pringle that accretion of electric charge by a black hole rotating in an aligned external magnetic field results in a “dead” vacuum magnetosphere, where the electric field is totally screened, no vacuum breakdown is possible, and the Blandford-Znajek mechanism cannot operate. Here we study in details the properties of the Wald solution for electrically charged black holes discussed in their paper. Our results show that the claim is erroneous as in the solution with the critical charge q0 = 2aB0 there exists a drop of electrostatic potential along all magnetic field lines except the one coinciding with the symmetry axis. It is also found that while uncharged rotating black holes expel external vacuum magnetic field from their event horizon (the Meissner effect), electric charging of black holes pulls the magnetic field lines back on it, resembling what has been observed in some previous force-free, RMHD and PIC simulations of black hole magnetospheres. This suggests that accretion of electric charge may indeed be a feature of the black hole electrodynamics. However, our analysis shows that the value q0 of the BH charge given by Wald is likely to be only an upper limit, and that the actual value depends of the details of the magnetospheric physics.

Physical implications of massless objects

2021 ◽  
Vol 34 (2) ◽  
pp. 178-182
Author(s):  
Tong Wang
Keyword(s):  
Electric Fields ◽  
Electric Charge ◽  
Speed Of Light ◽  
Negative Mass ◽  
Classical Physics ◽  
Normal Mass ◽  
Electrically Charged

Normal massless objects have no mass but do have energy, and they always move at the speed of light. This article proposes another way to construct massless objects theoretically by combining normal mass and negative mass of equal magnitudes. Such objects have zero net mass, qualifying as massless, and can be used to investigate the behaviors of general massless objects. Particularly, two kinds of such proposed massless objects, neutral and electrically charged, are studied under the influences of gravity and electric fields. By excluding the factor of mass, it is discovered that the motion of electrically charged massless objects is counterintuitive. The physical implications of the motion of massless objects are analyzed in detail within the framework of classical physics. Some surprising results arise from these analyses, and possible explanations of these dilemmas lead to the possibility of a new relationship between electric charge and mass.

The floral volatile, methyl benzoate, from snapdragon (Antirrhinum majus) triggers phytotoxic effects in Arabidopsis thaliana

Planta ◽  
2007 ◽  
Vol 226 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Jun-ichiro Horiuchi ◽  
Dayakar V. Badri ◽  
Bruce A. Kimball ◽  
Florence Negre ◽  
Natalia Dudareva ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Methyl Benzoate ◽  
Antirrhinum Majus ◽  
Phytotoxic Effects ◽  
Floral Volatile

Cuticle characteristics and volatile emissions of petals in Antirrhinum majus

2003 ◽  
Vol 117 (3) ◽  
pp. 435-443 ◽  
Author(s):  
S. Mark Goodwin ◽  
Natalia Kolosova ◽  
Christine M. Kish ◽  
Karl V. Wood ◽  
Natalia Dudareva ◽  
...  
Keyword(s):  
Antirrhinum Majus ◽  
Volatile Emissions

scholarly journals Deciphering the Biotic and Climatic Factors That Influence Floral Scents: A Systematic Review of Floral Volatile Emissions

2020 ◽  
Vol 11 ◽  
Author(s):  
Gerard Farré-Armengol ◽  
Marcos Fernández-Martínez ◽  
Iolanda Filella ◽  
Robert R. Junker ◽  
Josep Peñuelas
Keyword(s):  
Systematic Review ◽  
Climatic Factors ◽  
Floral Scents ◽  
Volatile Emissions ◽  
Floral Volatile

scholarly journals An Experimental Test of the Classical Interpretation of the Kaluza Fifth Dimension

Physics ◽  
2020 ◽  
Vol 2 (4) ◽  
pp. 587-595
Author(s):  
Martin Tajmar ◽  
Lance L. Williams
Keyword(s):  
General Relativity ◽  
Gravitational Field ◽  
Electric Charge ◽  
Experimental Test ◽  
Rest Frame ◽  
Time Dilation ◽  
Fifth Dimension ◽  
Null Result ◽  
Dilation Effect ◽  
Electrically Charged

Kaluza was the first to realize that the four-dimensional gravitational field of general relativity and the classical electromagnetic field behave as if they were components of a five-dimensional gravitational field. We present a novel experimental test of the macroscopic classical interpretation of the Kaluza fifth dimension. Our experiment design probes a key feature of Kaluza unification—that electric charge is identified with motion in the fifth dimension. Therefore, we tested for a time dilation effect on an electrically charged clock. This test can also be understood as a constraint on time dilation from a constant electric potential of any origin. This is only the second such test of time dilation under electric charge reported in the literature, and a null result was obtained here. We introduce the concept of a charged clock in the Kaluza context, and discuss some ambiguities in its interpretation. We conclude that a classical, macroscopic interpretation of the Kaluza fifth dimension may require a timelike signature in the five-dimensional metric, and the associated absence of a rest frame along the fifth coordinate.

scholarly journals Phenotypic plasticity of floral volatiles in response to increasing drought stress

2018 ◽  
Vol 123 (4) ◽  
pp. 601-610 ◽  
Author(s):  
Diane R Campbell ◽  
Paula Sosenski ◽  
Robert A Raguso
Keyword(s):  
Soil Moisture ◽  
Phenotypic Plasticity ◽  
Water Content ◽  
Time Course ◽  
Leaf Gas Exchange ◽  
Floral Volatiles ◽  
Volatile Emissions ◽  
Wide Range ◽  
Non Linear ◽  
Floral Volatile

Abstract Background and Aims Flowers emit a wide range of volatile compounds which can be critically important to interactions with pollinators or herbivores. Yet most studies of how the environment influences plant volatiles focus on leaf emissions, with little known about abiotic sources of variation in floral volatiles. Understanding phenotypic plasticity in floral volatile emissions has become increasingly important with globally increasing temperatures and changes in drought frequency and severity. Here quantitative relationships of floral volatile emissions to soil water content were analysed. Methods Plants of the sub-alpine herb Ipomopsis aggregata and hybrids with its closest congener were subjected to a progressive dry down, mimicking the range of soil moistures experienced in the field. Floral volatiles and leaf gas exchange were measured at four time points during the drought. Key Results As the soil dried, floral volatile emissions increased overall and changed in composition, from more 1,3-octadiene and benzyl alcohol to higher representation of some terpenes. Emissions of individual compounds were not linearly related to volumetric water content in the soil. The dominant compound, the monoterpene α-pinene, made up the highest percentage of the scent mixture when soil moisture was intermediate. In contrast, emission of the sesquiterpene (E,E)-α-farnesene accelerated as the drought became more intense. Changes in floral volatiles did not track the time course of changes in photosynthetic rate or stomatal conductance. Conclusions This study shows responses of specific floral volatile organic compounds to soil moisture. The non-linear responses furthermore suggest that extreme droughts may have impacts that are not predictable from milder droughts. Floral volatiles are likely to change seasonally with early summer droughts in the Rocky Mountains, as well as over years as snowmelt becomes progressively earlier. Changes in water availability may have impacts on plant–animal interactions that are mediated through non-linear changes in floral volatiles.

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