scholarly journals Chlorophyll absorption and phytoplankton size information inferred from hyperspectral particulate beam attenuation

2020 ◽  
Vol 59 (22) ◽  
pp. 6765
Author(s):  
Henry F. Houskeeper ◽  
David Draper ◽  
Raphael M. Kudela ◽  
Emmanuel Boss
Keyword(s):  
Size Information ◽  
Beam Attenuation ◽  
Phytoplankton Size ◽  
Chlorophyll Absorption

Methylamine vanadate (nanovan) negative stain

1994 ◽  
Vol 52 ◽  
pp. 132-133
Author(s):  
James F. Hainfeld ◽  
Daniel Safer ◽  
Joseph S. Wall ◽  
Martha Simon ◽  
Beth Lin ◽  
...  
Keyword(s):  
Electron Beam ◽  
Low Dose ◽  
Biological Molecules ◽  
Positive Staining ◽  
Signal To Noise ◽  
Negative Stain ◽  
Beam Attenuation ◽  
Coarse Grains ◽  
Lower Contrast

Uranyl and tungstate compounds have found favor as negative stains because of their high scattering power relative to biological molecules. However, other properties, such as specimen preservation, resistance to alterations or crystallization in the electron beam, and signal to noise (S/N) ratio, are also important. It may be that lower density materials may have advantages in these areas. A new negative stain, methylamine vanadate, CH3 NH2.VO3 ("NanoVan"), offers a near physiological pH of 8, similar to phosphotungstate (pH 7) with much smoother background. It is also very stable in the electron beam with minimal granulation at a dose of l04 el / nm2 . The resolution obtainable with vanadate appears to be comparable to uranyl at low dose, but superior at higher dose where uranyl forms coarse grains (see Fig. 1). Problems with uranyl such as unwanted positive staining and need for pH below 4 can be avoided. The lower contrast permits use of thicker stain embedment for better preservation and less flattening without excessive beam attenuation.

Taking statistics courses may increase use of sample size information

2007 ◽  
Author(s):  
Natalie A. Obrecht ◽  
Gretchen B. Chapman ◽  
Rochel Gelman
Keyword(s):  
Sample Size ◽  
Size Information ◽  
Statistics Courses

Feasibility and effort estimation models for medium and small size information mining projects

2015 ◽  
Vol 47 ◽  
pp. 1-14 ◽  
Author(s):  
Pablo Pytel ◽  
Alejandro Hossian ◽  
Paola Britos ◽  
Ramón García-Martínez
Keyword(s):  
Effort Estimation ◽  
Information Mining ◽  
Size Information ◽  
Mining Projects ◽  
Estimation Models

scholarly journals Strain Sensor via Wood Anomalies in 2D Dielectric Array

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1022
Author(s):  
Rashid G. Bikbaev ◽  
Ivan V. Timofeev ◽  
Vasiliy F. Shabanov
Keyword(s):  
Higher Plants ◽  
Numerical Study ◽  
Reciprocal Lattice ◽  
Strain Sensing ◽  
Photonic Materials ◽  
Sensing Applications ◽  
Wide Range ◽  
Sensor Structure ◽  
Optical Behavior ◽  
Chlorophyll Absorption

Optical sensing is one of many promising applications for all-dielectric photonic materials. Herein, we present an analytical and numerical study on the strain-responsive spectral properties of a bioinspired sensor. The sensor structure contains a two-dimensional periodic array of dielectric nanodisks to mimic the optical behavior of grana lamellae inside chloroplasts. To accumulate a noticeable response, we exploit the collective optical mode in grana ensemble. In higher plants, such a mode appears as Wood’s anomaly near the chlorophyll absorption line to control the photosynthesis rate. The resonance is shown persistent against moderate biological disorder and deformation. Under the stretching or compression of a symmetric structure, the mode splits into a couple of polarized modes. The frequency difference is accurately detected. It depends on the stretch coefficient almost linearly providing easy calibration of the strain-sensing device. The sensitivity of the considered structure remains at 5 nm/% in a wide range of strain. The influence of the stretching coefficient on the length of the reciprocal lattice vectors, as well as on the angle between them, is taken into account. This adaptive phenomenon is suggested for sensing applications in biomimetic optical nanomaterials.

scholarly journals Detecting the halo heating from AGN feedback with ALMA

2019 ◽  
Vol 490 (4) ◽  
pp. 5134-5146 ◽  
Author(s):  
S Brownson ◽  
R Maiolino ◽  
M Tazzari ◽  
S Carniani ◽  
N Henden
Keyword(s):  
Star Formation ◽  
Correction Factor ◽  
Spatial Scales ◽  
Complex Structure ◽  
Host Galaxy ◽  
Cosmological Simulations ◽  
Beam Attenuation ◽  
Gas Accretion ◽  
Marginal Detection ◽  
Compact Sources

ABSTRACT The Sunyaev–Zel’dovich (SZ) effect can potentially be used to investigate the heating of the circumgalactic medium and subsequent suppression of cold gas accretion on to the host galaxy caused by quasar feedback. We use a deep ALMA observation of HE0515-4414 in band 4, the most luminous quasar known at the peak of cosmic star formation (z = 1.7), to search for the SZ signal tracing the heating of the galaxy’s halo. ALMA’s sensitivity to a broad range of spatial scales enables us to disentangle emitting compact sources from the negative, extended SZ signal. We obtain a marginal SZ detection (∼3.3σ) on scales of about 300 kpc (30–40 arcsec), at the 0.2 mJy level, 0.5 mJy after applying a correction factor for primary beam attenuation and flux that is resolved out by the array. We show that our result is consistent with a simulated ALMA observation of a similar quasar in the fable cosmological simulations. We emphasize that detecting an SZ signal is more easily achieved in the visibility plane than in the (inferred) images. We also confirm a marginal detection (3.2σ) of a potential SZ dip on smaller scales (<100 kpc) already claimed by other authors, possibly highlighting the complex structure of the halo heating. Finally, we use SZ maps from the fable cosmological simulations, convolved with ALMA simulations, to illustrate that band 3 observations are much more effective in detecting the SZ signal with higher significance, and discuss the optimal observing strategy.

scholarly journals Links between Phenology of Large Phytoplankton and Fisheries in the Northern and Central Red Sea

2021 ◽  
Vol 13 (2) ◽  
pp. 231
Author(s):  
John A. Gittings ◽  
Dionysios. E. Raitsos ◽  
Robert J. W. Brewin ◽  
Ibrahim Hoteit
Keyword(s):  
Red Sea ◽  
Phytoplankton Bloom ◽  
Size Structure ◽  
Management Strategies ◽  
Trophic Levels ◽  
Cell Diameter ◽  
Food Web Structure ◽  
Marine Management ◽  
Fisheries Resources ◽  
Phytoplankton Size

Phytoplankton phenology and size structure are key ecological indicators that influence the survival and recruitment of higher trophic levels, marine food web structure, and biogeochemical cycling. For example, the presence of larger phytoplankton cells supports food chains that ultimately contribute to fisheries resources. Monitoring these indicators can thus provide important information to help understand the response of marine ecosystems to environmental change. In this study, we apply the phytoplankton size model of Gittings et al. (2019b) to 20-years of satellite-derived ocean colour observations in the northern and central Red Sea, and investigate interannual variability in phenology metrics for large phytoplankton (>2 µm in cell diameter). Large phytoplankton consistently bloom in the winter. However, the timing of bloom initiation and termination (in autumn and spring, respectively) varies between years. In the autumn/winter of 2002/2003, we detected a phytoplankton bloom, which initiated ~8 weeks earlier and lasted ~11 weeks longer than average. The event was linked with an eddy dipole in the central Red Sea, which increased nutrient availability and enhanced the growth of large phytoplankton. The earlier timing of food availability directly impacted the recruitment success of higher trophic levels, as represented by the maximum catch of two commercially important fisheries (Sardinella spp. and Teuthida) in the following year. The results of our analysis are essential for understanding trophic linkages between phytoplankton and fisheries and for marine management strategies in the Red Sea.

Serving sizes and energy values on the nutrition labels of regular and diet/light processed and ultra-processed dairy products sold in Brazil

2016 ◽  
Vol 118 (7) ◽  
pp. 1579-1593 ◽  
Author(s):  
Priscila Pereira Machado ◽  
Mariana Vieira dos Santos Kraemer ◽  
Nathalie Kliemann ◽  
Cláudia Flemming Colussi ◽  
Marcela Boro Veiros ◽  
...  
Keyword(s):  
Energy Density ◽  
Dairy Products ◽  
Dairy Product ◽  
Accurate Information ◽  
Nutrition Labels ◽  
Content Type ◽  
Size Information ◽  
Nutrition Labelling ◽  
Serving Sizes ◽  
Serving Size

Purpose – The purpose of this paper is to analyse and compare the serving sizes and energy values reported on the nutrition information of all processed and ultra-processed dairy products in their regular and diet/light versions available for sale in a large supermarket in Brazil. Design/methodology/approach – A check was done for associations between the compliance of reported serving sizes, energy values per serving and energy density for regular foods and foods advertised at “diet/light” (with reduced fat and calories). Findings – The data included information from 451 dairy product labels. Most of the products had serving sizes smaller than the reference set by Brazilian law. A high variability of serving sizes was found for similar products. “Diet/light” foods tend to report serving sizes that are even smaller and more inadequate. Moreover, the energy density of these products was similar to that of the regular foods. Smaller serving sizes may be being presented on “diet/light” foods in order to report lower energy values and on similar foods to show non-existent differences in energy values. These results point to the importance of standardizing serving size information on food labels so that consumers have access to clear and accurate information about food products. Originality/value – This was the first census-type study to analyse the serving size information of dairy products at a supermarket of one of the ten largest supermarket chains in Brazil. This work extends the scope of current food labelling and contributes to the discussion about how nutrition labelling has been presented to Brazilian consumers and its possible consequences for food choices and the guarantee of consumer rights.

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