Spectral efficiency and microstructure of the compound eyes of Synanthedon myopaeformis (Lepidoptera: Sesiidae)

2013 ◽  
Vol 145 (5) ◽  
pp. 529-538 ◽  
Author(s):  
C. Eby ◽  
M. Weis ◽  
M.G.T. Gardiner ◽  
G.J.R. Judd ◽  
G. Gries
Keyword(s):  
Spectral Efficiency ◽  
Spectral Reflectance ◽  
Compound Eyes ◽  
Primary Role ◽  
Floral Nectar ◽  
Uv Reflectance ◽  
Clearwing Moth ◽  
Asclepias Speciosa ◽  
Diurnal Behaviour ◽  
Nm Range

AbstractThe apple clearwing moth, Synanthedon myopaeformis (Borkhausen) (Lepidoptera: Sesiidae), is a day-flying species that feeds on floral nectar of many plants. In British Columbia, Canada, this invasive moth is often observed feeding on visually conspicuous showy milkweed, Asclepias speciosa Torrey (Apocynaceae). We measured the spectral efficiency of the compound eyes of S. myopaeformis in the context of their capacity to discriminate the measured spectral reflectance from inflorescences of A. speciosa, and conducted histological examination of these eyes to determine whether they possess apposition type ommatidia, as commonly observed in diurnal butterflies. Light micrographs of the compound eyes in S. myopaeformis revealed eucone apposition type ommatidia, which is consistent with the diurnal behaviour of the moth. Electroretinograms on compound eyes revealed they were particularly efficient at absorbing ultraviolet (UV) wavelengths in the 335–370 nm range and green wavelengths in the 495–560 nm range. These results support the conclusion that the compound eyes of S. myopaeformis have the capacity for dichromatic vision based on UV and green photoreceptors. However, spectral reflectance curves obtained from inflorescences and foliage of A. speciosa revealed no evidence of UV reflectance, making it less likely that colour plays a primary role in the attraction of S. myopaeformis to A. speciosa.

scholarly journals Experimental assessment of the sources of regulated and unregulated nanoparticles in gasoline direct-injection engines

2018 ◽  
Vol 20 (1) ◽  
pp. 128-140 ◽  
Author(s):  
Michele Bardi ◽  
Guillaume Pilla ◽  
Xavier Gautrot
Keyword(s):  
Liquid Film ◽  
Direct Injection ◽  
Optical Diagnostics ◽  
Gasoline Direct Injection ◽  
Small Range ◽  
Primary Role ◽  
Pool Fires ◽  
Direct Injection Engines ◽  
Relative Contribution ◽  
Nm Range

This work investigates nanoparticles formation process in light-duty gasoline direct-injection engines operated in homogeneous combustion. The analysis specifically focuses on the contribution of particles in the range of 10–23 nm, which are expected to be taken into account in future emission regulations. Experiments were carried out on a single-cylinder 0.4-L displacement gasoline direct-injection optical engine. Exhaust gases were analyzed by means of a commercial device (DMS500) to obtain a quantitative measurement of the particulates number and size. Optical diagnostics (broadband color imaging and liquid phase laser-induced fluorescence) were employed to correlate the exhaust measurements to the in-cylinder physical phenomena. The main leverages to control soot particulates formation were investigated. The engine temperature was found to have a significant impact during the entire warm-up phase on the global particulates number and also on the relative contribution of the 10–23 nm range to the total particulates number. Injection phasing has also a primary role in the formation of particulates in the small range of the spectrum when operating in mild stratified combustion mode. On the other hand, an increased in-cylinder aerodynamic (e.g. combined swirl-tumble motion) has a positive impact in reducing global particulates number but also causes an increase of the 10–23 nm relative contribution. Optical diagnostics helped establishing a relationship between the detection of liquid film, the consequent pool fires and the exhaust gas measurements. The evaporation of the liquid film detected on the injector nozzle and the intake valve right after the injection appears to be decisive for the formation of nanoparticles in pool-fire mode. The experimental results indicate that when pool fires were detected, the particulates number increased drastically in the whole range of the spectrum including the 10–23 nm range. Authors relate this effect to in-homogeneities in the fuel-mixing field induced by the evaporation of the liquid film.

scholarly journals Examining the possibility of correcting imagery acquired for the purpose of obtaining spectral reflectance coefficients in the infrared range using photometric measurements

2014 ◽  
Vol XL-1 ◽  
pp. 351-353 ◽  
Author(s):  
A. Orych ◽  
P. Walczykowski ◽  
M. Kedzierski ◽  
A. Fryskowska
Keyword(s):  
Spectral Reflectance ◽  
Reference Panel ◽  
Infrared Range ◽  
Lighting Conditions ◽  
Series Of Experiments ◽  
Photometric Measurements ◽  
Reflectance Data ◽  
Nm Range

The purpose of this paper is to determine the possibility of using photometric measurements in order to correct imagery acquired in the 900–1700 nm range. This imagery is acquired for the purpose of acquiring spectral reflectance coefficients in variable lighting conditions. This paper will present a series of experiments, the problems encountered and obtained results. The main aim of this research was to determine a link between these two quantities (luminance and irradiance) in order to be able to eliminate the need of using such a spectroradiometer (a large, heavy and costly instrument) when acquiring spectral reflectance data from a XEVA XS-1.7.320 camera mounted on an UAV without using a reference panel.

Interpretation of Uv Reflectance Measurements on Silicon-On-Sapphire By Spectral Reflectance and Spectroscopic Ellipsometry Studies

1985 ◽  
Vol 53 ◽  
Author(s):  
C. Pickering ◽  
A.M. Hodge ◽  
A.C. Daw ◽  
D.J. Robbins ◽  
P.J. Pearson ◽  
...  
Keyword(s):  
Spectroscopic Ellipsometry ◽  
Spectral Reflectance ◽  
Wavelength Dependence ◽  
Surface Scattering ◽  
Effective Medium Approximation ◽  
Relative Importance ◽  
Surface Layers ◽  
Scattering Effects ◽  
Uv Reflectance ◽  
Reflectance Measurements

ABSTRACTSpectral reflectance and spectroscopic ellipsometry measurements have been made on SOS wafers with haze ratings 1-5. The wavelength dependence of reflectance is dominated by surface scattering, but degraded crystallinity effects are also observed, and are significant in some samples. Analysis of dielectric function spectra using an effective medium approximation has indicated the presence of α-Si and voids in surface layers up to 300Å thick in medium haze wafers, with concentrations decreasing away from the surface. The assessment parameter normally used for SOS, UVR No., has been shown to includeboth crystallinity and scattering effects, and their relative importance cannot be determined without more detailed measurements.

Classification of sugarcane varieties using visible/near infrared spectral reflectance of stalks and multivariate methods

2018 ◽  
Vol 156 (4) ◽  
pp. 537-546
Author(s):  
A. J. Steidle Neto ◽  
D. C. Lopes ◽  
J. V. Toledo ◽  
S. Zolnier ◽  
T. G. F. Silva
Keyword(s):  
Discriminant Analysis ◽  
Spectral Reflectance ◽  
Near Infrared ◽  
External Validation ◽  
Principal Component ◽  
Validation Data ◽  
Sugarcane Varieties ◽  
Non Destructive ◽  
Factorial Discriminant Analysis ◽  
Nm Range

AbstractThe use of fast and non-destructive techniques for identifying sugarcane varieties enables the development of automatic sorting systems, contributing towards improving pre-processing steps in the alcohol and sugar industries. In this context, principal component analysis (PCA), factorial discriminant analysis (FDA), stepwise forward discriminant analysis (SFDA) and partial least-squares discriminant analysis (PLS-DA) were used to classify four Brazilian sugarcane varieties based on visible/near infrared (Vis/NIR) spectral reflectance measurements (450–1000 nm range) of stalks. All wavelengths contributed towards discriminating the sugarcane varieties, but the 600–750 nm range was most relevant. When evaluating PCA results considering the four sugarcane varieties, two of them overlapped and it was only possible to use classifiers of three varieties. Factorial discriminant analysis, PLS-DA and SFDA reached correct classifications of 0.81, 0.82 and 0.74, respectively, when considering the external validation data and the four sugarcane varieties evaluated. Results showed that Vis/NIR spectroscopy combined with discriminating methods is a promising tool for non-destructive and fast sugarcane variety classification, which can be used in the agro-food industry or directly in the field.

Bark reflectance spectra of conifers and angiosperms: implications for host discrimination by coniferophagous bark and timber beetles

2005 ◽  
Vol 137 (6) ◽  
pp. 719-722 ◽  
Author(s):  
Stuart A. Campbell ◽  
John H. Borden
Keyword(s):  
Visual System ◽  
Spectral Reflectance ◽  
Visual Cues ◽  
Host Plants ◽  
Green Light ◽  
Phytophagous Insects ◽  
Host Discrimination ◽  
Environmental Light ◽  
Reflected Light ◽  
Uv Reflectance

The spectral reflectance of phytophagous insects' host plants is usually quantified between 300–350 nm (ultraviolet, UV) and 700 nm (farred to infrared), and the shape and magnitude of the distribution of reflected light determine the hue, saturation, and intensity perceived by insects (Moericke 1969). Host perception also depends on the distribution of environmental light (Endler 1993) and on the constraints of the insects' visual system, which is usually described as dichromatic, with one type of photoreceptor responding maximally to blue light (λmax = ca. 400–470 nm) and another to green light (λmax = ca. 500–530 nm). UV receptors also appear to be common, if not ubiquitous (Briscoe and Chittka 2001; Mazza et al. 2002). Several phytophagous insects have been shown to use visual cues, including UV reflectance, to locate and (or) discriminate among plants (Prokopy and Owens 1983).

Structure of Myosin Subfragment-1 from Electron Microscopy and Crystallography

1988 ◽  
Vol 46 ◽  
pp. 156-157
Author(s):  
Donald A. Winkelmann
Keyword(s):  
Electron Microscopy ◽  
Molecular Weight ◽  
Actin Filaments ◽  
Light Chains ◽  
Myosin Filament ◽  
Primary Role ◽  
Heavy Chains ◽  
Myosin Subfragment ◽  
Myosin Subfragment 1 ◽  
Globular Head

The primary role of the interaction of actin and myosin is the generation of force and motion as a direct consequence of the cyclic interaction of myosin crossbridges with actin filaments. Myosin is composed of six polypeptides: two heavy chains of molecular weight 220,000 daltons and two pairs of light chains of molecular weight 17,000-23,000. The C-terminal portions of the myosin heavy chains associate to form an α-helical coiled-coil rod which is responsible for myosin filament formation. The N-terminal portion of each heavy chain associates with two different light chains to form a globular head that binds actin and hydrolyses ATP. Myosin can be fragmented by limited proteolysis into several structural and functional domains. It has recently been demonstrated using an in vitro movement assay that the globular head domain, subfragment-1, is sufficient to cause sliding movement of actin filaments.The discovery of conditions for crystallization of the myosin subfragment-1 (S1) has led to a systematic analysis of S1 structure by x-ray crystallography and electron microscopy. Image analysis of electron micrographs of thin sections of small S1 crystals has been used to determine the structure of S1 in the crystal lattice.

Immunogold localization of calmodulin in root caps of the maize Cultivar Merit

1990 ◽  
Vol 48 (3) ◽  
pp. 674-675
Author(s):  
P.T. Nguyen ◽  
C. Uphoff ◽  
C.L. Stinemetz
Keyword(s):  
Calcium Binding ◽  
Calcium Transport ◽  
Primary Role ◽  
Immunogold Localization ◽  
Root Tips ◽  
Electrical Currents ◽  
Considerable Evidence ◽  
Maize Cultivar ◽  
Gravity Response ◽  
Induced Changes

Considerable evidence suggest that the calcium-binding protein calmodulin (CaM) may mediate calcium action and/or transport important in the gravity response of plants. Calmodulin is present in both shoots and roots and is capable of regulating calcium transport in plant vesicles. In roots calmodulin is concentrated in the tip, the gravisensing region of the root; and is reported to be closely associated with amyloplasts, organelles suggested to play a primary role in gravi-perception. Inhibitors of CaM such as chlorpromazine, calmidazolium, and compound 48/80 interfere with the gravitropic response of both snoots and roots. The magnitude of the inhibition corresponded well with the extent to which the drug binds to endogenous CaM. Compound 48/80 and calmidazolium block gravi-induced changes in electrical currents across root tips, a phenomenon thought to be associated with the sensing of the gravity stimulus.In this study, we have investigated the subcellular distribution of CaM in graviresponsive and non-graviresponsive root caps of the maize cultivar Merit.

Differentiation Processes of the Ocellar Retina of the Honeybee (Apis Mellifera L.)

1990 ◽  
Vol 48 (3) ◽  
pp. 430-431
Author(s):  
Maria Anna Pabst
Keyword(s):  
Apis Mellifera ◽  
Distal Part ◽  
Cell Layer ◽  
Single Layer ◽  
Photoreceptor Cells ◽  
Distal Segment ◽  
Compound Eyes ◽  
Thin Sections ◽  
Ultrastructural Studies ◽  
Adult Worker

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).

The Psychosocial Aspects of Feeding in the Neonatal Intensive Care Unit and Beyond

2019 ◽  
Vol 4 (6) ◽  
pp. 1507-1515
Author(s):  
Lauren L. Madhoun ◽  
Robert Dempster
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Neonatal Intensive Care Unit ◽  
Hospital Discharge ◽  
Neonatal Intensive Care ◽  
Oral Feeding ◽  
Medical Attention ◽  
Primary Role ◽  
Speech Language Pathologists ◽  
The Family

Purpose Feeding challenges are common for infants in the neonatal intensive care unit (NICU). While sufficient oral feeding is typically a goal during NICU admission, this can be a long and complicated process for both the infant and the family. Many of the stressors related to feeding persist long after hospital discharge, which results in the parents taking the primary role of navigating the infant's course to ensure continued feeding success. This is in addition to dealing with the psychological impact of having a child requiring increased medical attention and the need to continue to fulfill the demands at home. In this clinical focus article, we examine 3 main areas that impact psychosocial stress among parents with infants in the NICU and following discharge: parenting, feeding, and supports. Implications for speech-language pathologists working with these infants and their families are discussed. A case example is also included to describe the treatment course of an infant and her parents in the NICU and after graduation to demonstrate these points further. Conclusion Speech-language pathologists working with infants in the NICU and following hospital discharge must realize the family context and psychosocial considerations that impact feeding progression. Understanding these factors may improve parental engagement to more effectively tailor treatment approaches to meet the needs of the child and family.

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