scholarly journals A Polyakov Formula for Sectors

2017 ◽  
Vol 28 (2) ◽  
pp. 1773-1839 ◽  
Author(s):  
Clara L. Aldana ◽  
Julie Rowlett
Keyword(s):  
Heat Kernel ◽  
Explicit Expression ◽  
Unit Area ◽  
Logarithmic Singularity ◽  
Conformal Factor ◽  
Opening Angle ◽  
Conformal Deformation ◽  
Finite Area ◽  
Different Parts

Abstract We consider finite area convex Euclidean circular sectors. We prove a variational Polyakov formula which shows how the zeta-regularized determinant of the Laplacian varies with respect to the opening angle. Varying the angle corresponds to a conformal deformation in the direction of a conformal factor with a logarithmic singularity at the origin. We compute explicitly all the contributions to this formula coming from the different parts of the sector. In the process, we obtain an explicit expression for the heat kernel on an infinite area sector using Carslaw–Sommerfeld’s heat kernel. We also compute the zeta-regularized determinant of rectangular domains of unit area and prove that it is uniquely maximized by the square.

Investigations of Grinding Forces for Nanostructured WC/12Co Coatings

2006 ◽  
Vol 304-305 ◽  
pp. 151-155 ◽  
Author(s):  
Zhao Hui Deng ◽  
Bi Zhang ◽  
F. Cheng
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Unit Area ◽  
The Other ◽  
Surface Grinding ◽  
Depth Of Cut ◽  
Grinding Forces ◽  
Theoretical Investigations ◽  
Grinding Machine ◽  
Different Parts

This study focuses on experimental and theoretical investigations of grinding forces for nanostructured WC/12Co coatings. In this study, nanostructured WC/12Co coatings are ground on a precision surface-grinding machine with four diamond wheels of two bond types and three grit sizes. A mathematical model is proposed to predict grinding forces per unit area and per grit, and is used to fit the experimental data. The model is also subsectioned into two different parts with one part fitting grinding forces for the smaller grit depth of cut condition and the other part for the larger grit depth of cut condition. Grinding mechanisms are also discussed in terms of grinding forces and grit depth of cut.

scholarly journals Increasing pechay (Brassica rapa L. ssp. chinensis) production through suitable seedling establishment under two cultivation systems in the Southern Philippines

2017 ◽  
pp. 129-136
Author(s):  
Zenaida Gonzaga ◽  
Othello Capuno ◽  
Marina Labonite ◽  
Eugenia Lonzaga ◽  
Nemisio Francisco Napuran ◽  
...  
Keyword(s):  
Unit Area ◽  
The Philippines ◽  
Direct Seeding ◽  
Root Characteristics ◽  
Cultivation Systems ◽  
Protected Cultivation ◽  
Short Period ◽  
Production Period ◽  
Leaf Vegetable ◽  
Different Parts

Seedling management is very important in leafy vegetable with short period of growing as it covers almost half of the production period. Pechay is considered a high value and a highly demanded leaf vegetable in the Philippines. These studies were conducted to determine the best method of raising pechay seedlings including direct seeding, seed box and seedling tray under two cultivation systems in different provinces of southern Philippines namely Bohol, Leyte and Samar. The studies were conducted in each province and data were consolidated and combined. Protected cultivation slightly manifested benefits on survival, root characteristics and yield except in Bohol where 3 times fold yield of plants under protective structure than open field. There was better survival and yield of using seedling tray. The unfavorable method was seed box in Bohol and Leyte while direct seeding in Samar as evident by low survival and yield. Among the three provinces in southern Philippines, Leyte produced the highest yield of pechay per unit area. This suggests that no similar method of raising seedlings was effective in different parts of southern Philippines.

EFFECTS OF FERTILIZER-NITROGEN AND WATER SUPPLY ON DISTRIBUTION OF DRY MATTER AND NITROGEN BETWEEN THE DIFFERENT PARTS OF WHEAT

1970 ◽  
Vol 50 (6) ◽  
pp. 613-625 ◽  
Author(s):  
E. D. SPRATT ◽  
J. K. R. GASSER
Keyword(s):  
Dry Matter ◽  
Unit Area ◽  
N Uptake ◽  
Nitrification Inhibitor ◽  
Early Growth ◽  
Fertilizer N ◽  
Boot Stage ◽  
Nitrate N ◽  
Ammonium N ◽  
Different Parts

Wheat in pots and in the field was subjected to different watering regimes and fertilizer-N, either as ammonium-N with a nitrification inhibitor or as nitrate-N, was applied at sowing or during growth. More weight of leaves and stems was produced during early growth with ammonium-N than with nitrate-N, but the two forms gave similar yields of grain. The grain:straw ratio with ammonium-N was smaller than with nitrate-N, and more N was retained in the straw. Both forms of N increased the weight per spike but not the number of spikes per unit area (tillering). Applied at the boot stage of growth, N increased dry matter much less than when applied at sowing, but increased the percent N in the grain. Divided dressings, half at sowing and half during growth, increased yield and N uptake by the same amount as applying all the N at sowing. Drought during spike formation or floret development led to smaller spikes and yields of grain, and also to a smaller grain:straw ratio; up to three-quarters of the extra N taken up from fertilizer-N remained in the straw.

Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 260-261
Author(s):  
Robert M. Glaeser
Keyword(s):  
High Resolution ◽  
Particle Flux ◽  
Unit Area ◽  
Signal To Noise ◽  
Resolution Image ◽  
High Resolution Image ◽  
Pass Through ◽  
Counting Statistics ◽  
The Relationship ◽  
Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

Reconstruction of Objects from their Projections Using Orthogonal Functions

1973 ◽  
Vol 31 ◽  
pp. 268-269
Author(s):  
Elrnar Zeitler
Keyword(s):  
Unit Area ◽  
Three Dimensional ◽  
One Dimension ◽  
Spatial Density ◽  
Dimensional Representation ◽  
Orthogonal Functions ◽  
Object A ◽  
Plane Normal ◽  
Dimensional Object ◽  
Spatial Density Distribution

Considering any finite three-dimensional object, a “projection” is here defined as a two-dimensional representation of the object's mass per unit area on a plane normal to a given projection axis, here taken as they-axis. Since the object can be seen as being built from parallel, thin slices, the relation between object structure and its projection can be reduced by one dimension. It is assumed that an electron microscope equipped with a tilting stage records the projectionWhere the object has a spatial density distribution p(r,ϕ) within a limiting radius taken to be unity, and the stage is tilted by an angle 9 with respect to the x-axis of the recording plane.

Morphometric SEM study of the effects of ACTH on endothelial fenestrae in the rat adrenal cortex

1984 ◽  
Vol 42 ◽  
pp. 234-235
Author(s):  
J. Curtis ◽  
K. S. Schwartz ◽  
R. P. Apkarian
Keyword(s):  
Anterior Pituitary ◽  
Lipid Droplets ◽  
Adrenocorticotropic Hormone ◽  
Unit Area ◽  
High Density Lipoproteins ◽  
Capillary Endothelium ◽  
Zona Fasciculata ◽  
Sem Study ◽  
Saline Vehicle ◽  
Scanning Electron

A scanning electron microscope (SEM) study was made of the effect of adrenocorticotropic hormone (ACTH) on the size and numbers of fenestrae/unit area in the capillary endothelium of the zona fasciculata (ZF) of the rat adrenal. The stimulatory effect of ACTH on cholesterol uptake via high density lipoproteins in the rat and evidence for the secretion of glucocorticoids by exocytosis of lipid droplets described by Rhodin suggest that endothelial change may accompany these transport phenomena.Twelve rats received two Dexamethasone (DEX) ip injections (25 μg DEX/100 g body wt.), the first at 8 PM and the second at 8 AM the next day, to inhibit the release of endogenous ACTH by the anterior pituitary. The animals were then divided into two groups. Six animals received only saline vehicle and six rats received ACTH (100 ng/100 g body wt.).

The Application of Protein A-Gold Immunocytochemistry to Studies of Protein Secretion

1985 ◽  
Vol 43 ◽  
pp. 426-429
Author(s):  
George H. Herbener ◽  
Antonio Nanci ◽  
Moise Bendayan
Keyword(s):  
Tissue Section ◽  
Colloidal Gold ◽  
Unit Area ◽  
Protein A ◽  
Extracellular Proteins ◽  
Gold Complex ◽  
Second Step ◽  
Igg Antibodies ◽  
Tissue Sections ◽  
Antigenic Sites

Protein A-gold immunocytochemistry is a two-step, post-embedding labeling procedure which may be applied to tissue sections to localize intra- and extracellular proteins. The key requisite for immunocytochemistry is the availability of the appropriate antibody to react in an immune response with the antigenic sites on the protein of interest. During the second step, protein A-gold complex is reacted with the antibody. This is a non- specific reaction in that protein A will combine with most IgG antibodies. The ‘label’ visualized in the electron microscope is colloidal gold. Since labeling is restricted to the surface of the tissue section and since colloidal gold is particulate, labeling density, i.e., the number of gold particles per unit area of tissue section, may be quantitated with ease and accuracy.

Maximum Interlabial Pressures in Normal Speakers

1997 ◽  
Vol 40 (2) ◽  
pp. 400-404 ◽  
Author(s):  
Virginia A. Hinton ◽  
Winston M. C. Arokiasamy
Keyword(s):  
Speech Production ◽  
Contact Pressure ◽  
Direct Evidence ◽  
Unit Area ◽  
Jaw Movement ◽  
Contractile Forces ◽  
Contact Pressures ◽  
Muscle Contractile

It has been hypothesized that typical speech movements do not involve large muscular forces and that normal speakers use less than 20% of the maximum orofacial muscle contractile forces that are available (e.g., Amerman, 1993; Barlow & Abbs, 1984; Barlow & Netsell, 1986; DePaul & Brooks, 1993). However, no direct evidence for this hypothesis has been provided. This study investigated the percentage of maximum interlabial contact pressures (force per unit area) typically used during speech production. The primary conclusion of this study is that normal speakers typically use less than 20% of the available interlabial contact pressure, whether or not the jaw contributes to bilabial closure. Production of the phone [p] at conversational rate and intensity generated an average of 10.56% of maximum available interlabial pressure (MILP) when jaw movement was not restricted and 14.62% when jaw movement was eliminated.

The Diverging Collimator

1970 ◽  
Vol 09 (01) ◽  
pp. 84-94
Author(s):  
G. Muehllehner
Keyword(s):  
Unit Area ◽  
Field Of View ◽  
Imaging Camera ◽  
Good Agreement ◽  
Parallel Hole

SummaryThe diverging collimator makes it possible to increase the field of view of a radioisotope imaging camera. The larger field of view is obtained by sacrificing efficiency per unit area of the field of view while preserving the resolution of the system. This situation is analogous to that of the scanner, where the efficiency per unit area is inversely proportional to the total area scanned.Efficiency and resolution of diverging collimators can be calculated quite accurately as is evidenced by the good agreement between calculated and measured values. The problem of septum penetration, however, needs to be further investigated for both parallel-hole as well as diverging collimators, so that the influence of the shape and arrangement of the holes upon septum penetration is taken into account.

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