Natural soiling has a small effect on structurally-based plumage coloration

2011 ◽  
Vol 61 (4) ◽  
pp. 441-455 ◽  
Author(s):  
Adrian Surmacki
Keyword(s):  
Coherent Scattering ◽  
Color Variation ◽  
Plumage Coloration ◽  
Cyanistes Caeruleus ◽  
Chemical Cleaning ◽  
Structural Coloration ◽  
Visual Contrast ◽  
Signaling Function ◽  
Important Trait ◽  
The Impact

AbstractPlumage coloration is an important trait used by birds in mate choice decisions and is often an indicator of social status. The two main types of color-producing mechanisms in feathers are pigment deposition (pigmentary coloration) or the coherent scattering of light reflected from keratin microstructure (structural coloration). External factors acting on the feather surface are also hypothesized to affect structural coloration. Because preening is an energy and time demanding behavior, color variation caused by soiling deposition is generally assumed to strengthen the condition signaling function of plumage coloration. To date, studies using artificial soiling have confirmed those hypotheses. However, information about how natural soiling affects plumage color are still scarce. In this paper, I investigated the effect of natural soiling on structurally-based feather color of blue tits Cyanistes caeruleus. As a method, I applied mechanical cleaning that functionally mimicked natural preening. Removal of soiling caused a decrease of ultraviolet (UV) chroma in males and decrease in brightness in females. According to visual contrast modeling, only changes in brightness should be perceived by birds. Further, more efficient chemical cleaning resulted in a significant increase in brightness in both sexes, presumably due to preen wax removal. These results suggest that the impact of natural feather soiling is not likely to modify structural coloration signaling. One possible explanation is that, under natural conditions, the amount of soil accumulating on feathers is too small to affect coloration.

LMFBR Steam Generator Materials Development at Westinghouse

1983 ◽  
Vol 105 (4) ◽  
pp. 719-725 ◽  
Author(s):  
M. A. Hebbar ◽  
C. E. Sessions
Keyword(s):  
Water Chemistry ◽  
Corrosion Behavior ◽  
Tube Model ◽  
Expansion Joint ◽  
Chemical Cleaning ◽  
Materials Development ◽  
The Past ◽  
Component Design ◽  
The Impact ◽  
Double Wall

The impact of Materials and Processes (M and P) development activities at the Nuclear Components Division - Breeder Reactor Components Project of Westinghouse are described. Nine specific M and P programs have been performed over the past five years and the conclusions drawn from each are summarized herein. These engineering activities could be classified as component design, fabrication, and testing results. However, the discussion presented is from a materials engineer’s viewpoint as to how the previously proposed development tasks have answered existing questions about either design, manufacturing, or plant operation. The nine areas which are discussed include (i) double-wall tubing, (ii) tube-to-tubesheet welding, (iii) few tube model fabrication and testing, (iv) tube support plates, (v) shell welding, (vi) convoluted shell expansion joint, (vii) water chemistry and corrosion behavior, (viii) chemical cleaning, and (ix) surface contamination protection.

scholarly journals Subspecific and Temporal Variation in the Structurally Based Coloration of the Ultramarine Grosbeak

The Condor ◽  
2007 ◽  
Vol 109 (1) ◽  
pp. 187-192 ◽  
Author(s):  
Ana S. Barreira ◽  
Dario A. Lijtmaer ◽  
Stephen C. Lougheed ◽  
Pablo L. Tubaro
Keyword(s):  
Temporal Variation ◽  
Gradual Increase ◽  
Color Variation ◽  
Reflectance Spectra ◽  
Plumage Coloration ◽  
Sexual Dichromatism ◽  
Ambient Light ◽  
Uv Reflectance ◽  
Color Differences ◽  
Dark Blue

Abstract Abstract Ultramarine Grosbeaks (Cyanocompsa brissonii) possess a striking sexual dichromatism, with males dark blue and females brown. There are two subspecies in Argentina: the larger-bodied C. b. argentina, which is common in shrubs and semiopen areas, and the smaller C. b. sterea that inhabits forests. We measured reflectance spectra of six plumage patches from study skins to evaluate the possibility of color differences between males of each subspecies and temporal variation in plumage coloration. We found differences between subspecies in color brightness, hue, saturation, and UV chroma in the plumage patches of more conspicuous coloration, which could be related to ambient light differences between the environments that each subspecies inhabits. We also documented temporal color variation in some plumage patches, in particular a gradual decrease of UV reflectance and a gradual increase in hue after molting, possibly attributable to feather wear.

scholarly journals Optimal Check Size and Reversal Rate to Elicit Pattern-reversal MEG Responses

2005 ◽  
Vol 32 (2) ◽  
pp. 218-224 ◽  
Author(s):  
Wei-Ta Chen ◽  
Yu-Chieh Ko ◽  
Kwong-Kum Liao ◽  
Jen-Chuen Hsieh ◽  
Tzu-Chen Yeh ◽  
...  
Keyword(s):  
Cortical Activation ◽  
Pattern Reversal ◽  
Check Size ◽  
Size Dependent ◽  
Visual Contrast ◽  
Single Dipole ◽  
Dipole Modeling ◽  
Pattern Reversal Stimulation ◽  
Visual Cortical ◽  
The Impact

ABSTRACT:Objective:To determine the impact of check size and interstimulus interval (ISI) on neuromagnetic visual cortical responses.Methods:We recorded visual evoked fields to pattern-reversal stimulation with central occlusion in ten subjects. The ~100 ms magnetic activation (P100m) was analyzed by single dipole modeling.Results:With 1 s ISI, P100m strengths increased as check size increased from 15' up to 120' of visual arc, and larger checks elicited less P100m activation. With 120' checks, we found no P100m attenuation as ISI decreased from 4 s to 0.16 s. P100m sources around the calcarine sulcus did not vary with check size or ISI.Conclusions:The magnitude of cortical activation during visual contrast processing is check size-dependent and the 120' checks are optimum for future studies on neuromagnetic visual cortical functions using central-occluded stimulation. The corresponding neuronal activation demonstrated a short refractory period less than 0.16 s. We also found significantly overlapping cortical representation areas for different check sizes or ISIs.

scholarly journals The impact of anionic polyacrylamide (APAM) on ultrafiltration efficiency in flocculation-ultrafiltration process

2017 ◽  
Vol 75 (8) ◽  
pp. 1982-1989 ◽  
Author(s):  
Ruijun Zhang ◽  
Shengnan Yuan ◽  
Wenxin Shi ◽  
Cong Ma ◽  
Zhiqiang Zhang ◽  
...  
Keyword(s):  
Membrane Fouling ◽  
Aluminium Chloride ◽  
Optimal Dosage ◽  
Cleaning Efficiency ◽  
Chemical Cleaning ◽  
Membrane Cleaning ◽  
Effluent Quality ◽  
Adsorption Sites ◽  
The Impact ◽  
Anionic Polyacrylamide

With the purpose of improving the ultrafiltration (UF) efficiency, anionic polyacrylamide (APAM) has been used as a coagulant aid in the flocculation-UF process. In this study, the impact of APAM on UF efficiency has been investigated with regard to membrane fouling, membrane cleaning and effluent quality. The results indicated that the optimal dosage of APAM had positive impacts on membrane fouling control, membrane cleaning and effluent quality. According to the flux decline curve, scanning electron microscopy and contact angle characterization, the optimal dosage of APAM was determined to be 0.1 mg/L coupled with 2 mg/L (as Al3+) poly-aluminium chloride. Under this optimal condition, membrane fouling can be mitigated because of the formation of a porous and hydrophilic fouling layer. APAM in the fouling layer can improve the chemical cleaning efficiency of 0.5% NaOH due to the disintegration of the fouling layer when APAM is dissolved under strong alkaline conditions. Furthermore, with the addition of APAM in the flocculation-UF process, more active adsorption sites can be formed in the flocs as well as the membrane fouling layer, thus more antipyrine molecules in the raw water can be adsorbed and removed in the flocculation-UF process.

scholarly journals Evaluation of the quality of surface finish of messassa wood for three types of varnishes.

2020 ◽  
Vol 8 (2) ◽  
pp. 122-130
Author(s):  
Narciso Fernando Bila ◽  
Rosilani Trianoski ◽  
Andrade Fernando Egas ◽  
Setsuo Iwakiri ◽  
Marcio Pereira da Rocha
Keyword(s):  
Surface Finish ◽  
Solid Wood ◽  
Color Variation ◽  
Technical Standards ◽  
Coating Performance ◽  
Impact Deformation ◽  
Water Based ◽  
Brachystegia Spiciformis ◽  
The Impact

The aim of this study was to evaluate the performance of the messassa wood Brachystegia spiciformis and Julbernardia globiflora for three types of finishing products for use in the furniture and frames industries. Coating performance was assessed by adhesion strength, impact deformation resistance, abrasiveness, gloss and overall color variation tests based on technical standards. Copal painting application was higher for gloss, adhesion and lower abrasiveness compared to water based and polyurethane. The impact deformation was higher for polyurethane than water-based and copal for both species. The darkening of wood for Brachystegia spiciformis and a slight lightening of wood by Julbernardia globiflora characterize the overall color variation after application of the coating products. According to these results, the varnishes can be used to add value to the messassa wood as a finish in solid wood furniture and frames.

scholarly journals The Misregulation of Cell Adhesion Components during Tumorigenesis: Overview and Commentary

2010 ◽  
Vol 2010 ◽  
pp. 1-9 ◽  
Author(s):  
Claudia D. Andl
Keyword(s):  
Cell Adhesion ◽  
Embryonic Development ◽  
Cancer Progression ◽  
Epithelial Mesenchymal Transition ◽  
Mesenchymal Transition ◽  
Matrix Interaction ◽  
Cell Matrix ◽  
Signaling Function ◽  
The Common ◽  
The Impact

Cell adhesion complexes facilitate attachment between cells or the binding of cells to the extracellular matrix. The regulation of cell adhesion is an important step in embryonic development and contributes to tissue homeostasis allowing processes such as differentiation and cell migration. Many mechanisms of cancer progression are reminiscent of embryonic development, for example, epithelial-mesenchymal transition, and involve the disruption of cell adhesion and expression changes in components of cell adhesion structures. Tight junctions, adherens junctions, desmosomes, and focal adhesion besides their roles in cell-cell or cell-matrix interaction also possess cell signaling function. Perturbations of such signaling pathways can lead to cancer. This article gives an overview of the common structures of cell adhesion and summarizes the impact of their loss on cancer development and progression with articles highlighted from the present issue.

Spatial variation in carotenoid plumage coloration and relationships between female coloration and quality in Prothonotary Warblers (Protonotaria citrea)

The Auk ◽  
2019 ◽  
Vol 136 (2) ◽  
Author(s):  
Morgan C Slevin ◽  
Lesley P Bulluck ◽  
Alix E Matthews ◽  
Than J Boves
Keyword(s):  
Spatial Variation ◽  
Social Rank ◽  
Color Variation ◽  
Plumage Coloration ◽  
Female Quality ◽  
Bottomland Forests ◽  
Provisioning Rate ◽  
Nest Depredation ◽  
Prothonotary Warblers ◽  
Female Coloration

Abstract Many birds use conspicuous plumage coloration to signal quality for sexual or social selection. However, it is still often unclear how intraspecific coloration and associated signaling vary spatially. Plumage coloration that is dependent on carotenoids may be ideal for studying spatial color variation because birds cannot naturally synthesize this pigment; therefore, bird coloration from carotenoids is at least partially contingent upon diet. As food availability often varies spatially, so might color and its signaling strength. While male coloration has received more research focus, less is known about female coloration and its relationships with social rank or sexual quality. To further improve our understanding of spatial variation in plumage coloration and correlations with individual quality, we compared Prothonotary Warblers breeding at 2 ecologically disparate sites separated by 1,300 km: in bottomland forests of Arkansas, USA, and the forests near the tidal freshwater James River in Virginia, USA. We assessed crown and breast plumage coloration for both sexes and compared several color metrics between sites. We then assessed surrogates of female quality (number of young fledged, number of eggs laid, provisioning rate, apparent annual survival, and nest depredation) and compared coloration-quality relationships between sites. We found that coloration of birds breeding in Arkansas was generally more elaborate than those breeding in Virginia. However, this was somewhat dependent on sex: females showed greater differences than males between sites. Additionally, color metrics of females breeding in Virginia showed stronger relationships with quality (all 5 quality metrics) than for birds breeding in Arkansas (only provisioning rate and nest depredation). Proximately, spatial variation in plumage coloration and the associated signaling may be explained by differences in diet between sites. Ultimately, spatial variation in intra- and intersexual selection pressures may explain how spatial variation in plumage signal strength evolved.

How to manage vision problems

2021 ◽  
pp. 85-96
Author(s):  
Andrew E. Budson ◽  
Maureen K. O’Connor
Keyword(s):  
Visual Cues ◽  
Daily Activities ◽  
Eye Disease ◽  
Navigation Systems ◽  
Loved One ◽  
Visual Contrast ◽  
Eye Examination ◽  
The Impact

Whether caused by dementia or an eye disease, problems with vision can disrupt your loved one’s function, create hallucinations, and even lead them to think you are an imposter. There are, however, many things you can do to help. Start with an eye examination to make sure their eyeglasses prescription is correct and to look for treatable diseases. Ensure adequate lighting in and around their home and increase visual cues in potentially hazardous areas, such as stairs. Adjust for difficulty seeing or paying attention on one side. Increase visual contrast and size of numbers and letters for their daily activities. Use navigation systems with audible directions. Reduce the impact of hallucinations. Lastly, manage difficulties when your loved one does not recognize you, thinks you are someone else, or believes that you have been replaced by an imposter.

scholarly journals Effects of various chemical cleaning conditions for pressured MF process

2016 ◽  
Vol 75 (5) ◽  
pp. 1063-1070
Author(s):  
Chang-Kyu Lee ◽  
Chansoo Park ◽  
June-Seok Choi ◽  
Jong-Oh Kim
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Pilot Scale ◽  
Second Step ◽  
Fiber Membrane ◽  
Bag Filter ◽  
Chemical Cleaning ◽  
Pilot Plant Process ◽  
The Impact ◽  
Plant Process

A pilot-scale pressured hollow-fiber microfiltration (MF) process as pretreatment for the reverse osmosis process was studied and operated under various conditions to assess the relative influence of backwashing, chemical enhanced backwashing (CEB), and bag filter application. The pilot plant process consisted of backwashing but without the CEB or the bag filter as the first step of the research. As the second step of the research, the impact of the backwashing on permeability recovery was assessed at different intervals followed by the influence of CEB on flowrate recovery. Results from operating the pilot-scale hollow-fiber membrane modules for more than 1 year have demonstrated that the appropriate pore size of bag filters was 25–50 μm and the optimized backwashing process was every 30 minutes with 25 mg/L of NaOCl, and CEB with an interval of 10 cycles with the use of 100 mg/L NaOCl.

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