scholarly journals Path Meander of Male Codling Moths (Cydia pomonella) Foraging for Sex Pheromone Plumes: Field Validation of a Novel Method for Quantifying Path Meander of Random Movers Developed Using Computer Simulations

Insects ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 549
Author(s):  
Christopher Adams ◽  
Jeffrey Schenker ◽  
Paul Weston ◽  
Lawrence Gut ◽  
James Miller

Measures of path meander are highly relevant to studies of optimal foraging by animals. However, directly recording paths of small animals such as insects can be difficult because of small size or crepuscular activity. Computer simulations of correlated random walkers demonstrated that the rates of decay in captures across a rectangular grid of traps when movers were released at its corner can be used to produce calibration curves for quantifying path meander indirectly. Simulations using spatial parameters matching those previously documented for male codling moths (Cydia pomonella (L.)) foraging for female pheromone plumes in the field predicted that meander, as measured in circular standard deviation (c.s.d.) of turn angles between track segments, should be ca. 50° and 30° when the target population density is high vs. low, respectively. Thus, if optimized, the mean value measured for C. pomonella populations encountering an unknown target density should fall between these limits. We recorded decay in C. pomonella catch across a 5 × 5 grid of pheromone-baited traps each separated by 15 m on 39 occasions where batches of ca. 800 males were released 10 m outside the corner of trapping grids arranged in five large Michigan apple orchards. This decay constant was translated into mean c.s.d value for path meander using the standard curve generated by the computer simulations. The measured decay constant for C. pomonella males was negative 0.99 ± 0.02 (S.E.M.), which translates to a path meander of 37 ± 2° c.s.d. Thus, the measured path meander of 37° fell between the 50° and 30° values optimal for dense and sparse populations, respectively. In addition to providing a rare documented example of optimal foraging for odor plumes, this research offers proof-of-concept for a novel approach to quantifying path meander of movers that could prove useful across diverse taxa.

Designs ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 8
Author(s):  
Pyrrhon Amathes ◽  
Paul Christodoulides

Photography can be used for pleasure and art but can also be used in many disciplines of science, because it captures the details of the moment and can serve as a proving tool due to the information it preserves. During the period of the Apollo program (1969 to 1972), the National Aeronautics and Space Administration (NASA) successfully landed humans on the Moon and showed hundreds of photos to the world presenting the travel and landings. This paper uses computer simulations and geometry to examine the authenticity of one such photo, namely Apollo 17 photo GPN-2000-00113. In addition, a novel approach is employed by creating an experimental scene to illustrate details and provide measurements. The crucial factors on which the geometrical analysis relies are locked in the photograph and are: (a) the apparent position of the Earth relative to the illustrated flag and (b) the point to which the shadow of the astronaut taking the photo reaches, in relation to the flagpole. The analysis and experimental data show geometrical and time mismatches, proving that the photo is a composite.


2013 ◽  
Vol 14 (2) ◽  
pp. 308-321
Author(s):  
Lina Maria Peñuela Sierra ◽  
Ivan Moreira ◽  
Antonio Claudio Furlan ◽  
Paulo Levi de Oliveira Carvalho ◽  
Ângela Rocio Poveda Parra ◽  
...  

Two experiments were carried out to determine the bioavailability of phosphorus in two spray-dried yeasts - sugarcane yeast (SCY), and sugarcane yeast + brewer's yeast (SCBY) - in starting pigs, by comparing different methods (Apparent Digestibility Coefficient of Phosphorus - ADCP; True Digestibility Coefficient of Phosphorus - TDCP; slope ratio; and standard curve). In experiment I, a digestibility assay were carried out using 30 cross breed pig with initial weigh of 22.69 ± 4.24kg, allotted in a completely randomized design. The mean ADCP and TDCP values were 62.68 and 64.15% for SCY and 77.01 and 79.33% for SCBY. ADCP and TDCP for SCBY were higher (P<0.05) than the values for SCY. In Experiment II, a growth test was conducted, 56 crossbred piglets, were utilized, with initial live weight of 15.11 ± 3.43kg, allotted in a completely randomized design, with seven treatments, four replications, and two pigs per experimental unit. The treatments consisted of a basal diet without supplementation with P and the same diet including supplementation with two levels of P (0.053% and 0.105%) from dicalcium phosphate, SCY and SCBY. The relative bioavailability mean value of 57.23% for SCY and 91.96% for SCBY, corresponding to 0.30% and 0.40% of available phosphorus, respectively.


2012 ◽  
Vol 3 (3) ◽  
Author(s):  
Megen Leeds Schumacher ◽  
Ashley Cetola Pettia ◽  
Albert I Wertheimer

Background: Extended cycle hormonal contraceptives (e.g. Seasonale, Seasonique) when introduced in 2003 were considered a very novel approach to contraception. The idea of manipulating the menstrual cycle so that women would experience just four menstruations a year was radical and was assumed to be responsible for the slow acceptance rate among the general public. Objective: This report analyzes two different aspects of the acceptance of this unique idea in the population. The first was the level of usage of extended cycle hormonal contraceptives in the general population, which was measured by a review of sales figures over time in the United States. The second was an examination of market diffusion as it relates to consumer perceptions regarding the characteristics of these products. Methods: To determine the degree of usage of extended cycle hormonal contraceptives the yearly sales, in terms of units sold, were compared with that of other leading methods of hormonal contraception. Along with the data, survey answers were obtained from 65 women who volunteered to participate in the study. Participants were selected randomly to represent the target population to assess the level of awareness about the benefits, risks, and any other concerns regarding the use of extended cycle hormonal contraceptives. Results: The yearly sales data of units sold showed a definitive increase in the sales of extended cycle hormonal contraceptives since their release on the market. The survey results showed an overwhelming awareness in the study population about the extended regimen. However, only about half of the women in the survey group were aware of its benefits. The main concern reported was the perceived significant side effect profile. Conclusion: Though awareness about the extended cycle hormonal contraception regimen was widespread, the survey population was not well informed about the advantages and the disadvantages regarding the degree of severity of side effects. To address these knowledge deficits, these aspects should be the focus when distributing information about extended cycle hormonal contraceptive regimens. This may boost the use of a potentially advantageous contraceptive regimen by a population who would derive benefit from its usage.   Type: Original Research


1965 ◽  
Vol 56 (2) ◽  
pp. 377-388 ◽  
Author(s):  
M. Gratwick ◽  
J. M. Sillibourne ◽  
R. P. Tew

The persistence, as assessed by biological and chemical methods, of field deposits on apples from two spray programmes, each of DDT, carbaryl or azinphos-methyl, was compared throughout eight weeks following the first application in an orchard in south-eastern England. Newly emerged larvae of the codling moth, Cydia pomonella (L.), were used to assess, in the laboratory, the biological activity of the deposits. The spray programmes studied were (1) two applications of conventional concentrations (i.e., 0·1 per cent, for DDT and for carbaryl, 0·04 per cent, for azinphos-methyl) three weeks apart and (2) three applications of half these concentrations at two-weekly intervals. DDT wettable powder, carbaryl and azinphos-methyl were compared in 1961, DDT emulsion, DDT wettable powder and carbaryl in 1963. Results of biological and chemical assessment of the deposits are presented graphically. Over-all, the performance of the three-application programmes was as satisfactory as that of the two-application programmes, although a smaller amount of chemical was used. The serious reduction in deposit caused by heavy rain shortly after the first application of DDT wettable powder and of carbaryl in 1961 is noted. In the absence of heavy rain, carbaryl was biologically the most persistent, but the best performances of the other chemicals were almost as good as that of carbaryl.LD50 values of fresh deposits obtained by field spraying were shown to be similar to those obtained by laboratory dipping.Comparison of the toxicity of fresh and weathered field deposits of similar magnitude indicated that the biologically available proportion of a DDT deposit from either formulation decreases as a result of weathering. This phenomenon was not found to occur with carbaryl and either not at all or to a much lesser extent with azinphos-methyl.The deposits obtained in the comparison of the spray programmes were separated into their fresh and aged components, so that differences in the contribution to the final deposit provided by each application could be seen. With the very persistent DDT emulsion, only about half of the six-week deposits was composed of chemical from the final application, but, with the much less persistent carbaryl and azinphos methyl, the six-week deposits were almost entirely derived from the final application. By substitution in an equation to obtain the rates of decay of the deposits from the three-application programmes of all chemicals, it is shown that deposits from the second and third applications were, in all cases, more persistent than those from the first. Possible reasons for this difference are discussed.The significance, in terms of field control, of the results for the larvicidal activity of the deposits from the different spray programmes is indicated. It is concluded that data on the LD90 of insecticidal deposits on apples, together with measurement of their persistence in the field, can be used to assess the probable field performance of codling-moth insecticides and to determine the most efficient means of employing them, although the deposit level that ensures 90 per cent, larval mortality in the field is higher than the LD90 determined in the laboratory.


2007 ◽  
Vol 339 ◽  
pp. 147-151
Author(s):  
Chun Hua Ju ◽  
Yi Xie

Surface roughness is an important quality characteristic in grinding. Measurement of surface roughness by means of mechanical stylus is widely done in metrology. In this paper, a new machine vision system has been utilized to quantify the surface roughness of machined surfaces (ground and milled). Compared with other measurement methods, it is accurate, quick and credible. This system is mounted on the grinding machine and automates the measurement process by using computer control to automatically position the CCD and capture digital images of machined surfaces between grinding cycles. It was proposed that the proportional formula was used in calibrating this system, and calibration precision meets application requirement. Not only the statistic character of gray image but also which of edge image were calculated out. These characters include the mean value of pixels (Mean), standard deviation (σ), maximal value (Max) and minimal value (Min), the number of pixels on the examine line(Count), etc. It was found out that the standard deviation value σ of the gray image could express the surface roughness most. The correlation between σ and Ra is established by interpolating σ value used Lagrange interpolation law, and the σ value is converted into Ra value through the calculation procedure finally.


2021 ◽  
Vol 24 (3) ◽  
Author(s):  
Amr El-Etreby ◽  
Mahmoud Metwally ◽  
Gihan EL-Nagar

Objective: The recycling of heat pressed lithium disilicate glass-ceramic leftover material has been reported to be done by dental laboratories. The effect of this procedure on the fracture resistance of single crowns is unknown, especially when it is functioning inside the oral cavity with subsequent exposure to temperature changes and cycles of mastication. Material and Methods: A total of 28 lithium disilicate glass-ceramic crowns (IPS emax Press) were constructed and randomly assigned into two groups (n = 14); Group (P): Included crowns fabricated from new e.max ingots. Group (R): Included crowns fabricated from repressed e.max buttons. Specimens of each group were divided into two equal subgroups (n = 7) according to whether the aging of specimens will be performed or not before fracture resistance testing. Subgroup (N), samples were subjected to fracture resistance without thermo-mechanical aging, while subgroup (A), samples were subjected to thermo-cycling and cyclic loading before being subjected to fracture strength testing. Different methods; SEM, XRD, EDAX were used to characterize the properties of lithium disilicate glass-ceramics before and after repressing. Results: The highest statistically significant fracture resistance value was recorded for the subgroup (RN) repressed/non-aged, followed by the subgroup repressed/aged (RA), while the lowest statistically significant mean value was recorded for the subgroup pressed/aged (PA). There was no significant difference between pressed/non-aged (PN) and repressed/aged (RA) subgroups. Conclusion: Repressing of leftover buttons may increase the fracture resistance of IPS emax Press crowns. Thermo-mechanical aging may negatively affect the fracture resistance of IPS emax Press crowns, yet Repressing may decrease this effect. Clinical implications: This is a novel approach that targets a point of research that has not been investigated before. It elaborates how repressing may decrease the effect of aging and increase the fracture resistance of lithium disilicate crowns. Thus, recycling of lithium disilicate glass ceramics might decrease its failure and prolong their serviceability.   Keywords Fracture resistance; Heat pressed; Lithium disilicate; Recycling; Repressing; Thermo-mechanical aging.


2014 ◽  
Vol 60 (7) ◽  
pp. 963-973 ◽  
Author(s):  
Yoshimi Inaba ◽  
Charles E Schwartz ◽  
Quang M Bui ◽  
Xin Li ◽  
Cindy Skinner ◽  
...  

Abstract BACKGROUND Standard fragile X syndrome (FXS) diagnostic tests that target methylation of the fragile X mental retardation 1 (FMR1) CpG island 5′ of the CGG expansion can be used to predict severity of the disease in males from birth, but not in females. METHODS We describe methylation specific–quantitative melt analysis (MS-QMA) that targets 10 CpG sites, with 9 within FMR1 intron 1, to screen for FXS from birth in both sexes. The novel method combines the qualitative strengths of high-resolution melt and the high-throughput, quantitative real-time PCR standard curve to provide accurate quantification of DNA methylation in a single assay. Its performance was assessed in 312 control (CGG &lt;40), 143 premutation (PM) (CGG 56–170), 197 full mutation (FM) (CGG 200–2000), and 33 CGG size and methylation mosaic samples. RESULTS In male and female newborn blood spots, MS-QMA differentiated FM from control alleles, with sensitivity, specificity, and positive and negative predictive values between 92% and 100%. In venous blood of FM females between 6 and 35 years of age, MS-QMA correlated most strongly with verbal IQ impairment (P = 0.002). In the larger cohort of males and females, MS-QMA correlated with reference methods Southern blot and MALDI-TOF mass spectrometry (P &lt; 0.05), but was not significantly correlated with age. Unmethylated alleles in high-functioning FM and PM males determined by both reference methods were also unmethylated by MS-QMA. CONCLUSIONS MS-QMA has an immediate application in FXS diagnostics, with a potential use of its quantitative methylation output for prognosis in both sexes.


ACTA IMEKO ◽  
2015 ◽  
Vol 4 (4) ◽  
pp. 20 ◽  
Author(s):  
Ahmad Barari ◽  
Saeed Jamiolahmadi

<p class="Abstract">In order to comprehend an entire surface's deviation zone, infinite measured points are required. Using the common measurement techniques through coordinate metrology, a limited number of surface actual points can be acquired. However, the obtained points would not provide sufficient information to examine the geometry thoroughly. A novel approach to predict surface behaviour via Distribution of Geometric Deviations (DGD) is examined in this paper. The methodology governs the mean value property of the harmonic functions to solve Laplace equation around each measured point. This DGD model can be used to reconstruct surface deviation values at any unmeasured point of the inspected surface based on a limited number of measured points. The convergence of the introduced approach is studied in this paper. A complete approach to implement the developed methodology is described, and the validation process is studied using actual case studies and mathematical functions. This methodology is practical in closed-loop inspection and manufacturing processes to form a scheme for compensating the surface errors during manufacturing process based on the DGD model.</p>


2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
P. Babu ◽  
V. Rajamani ◽  
K. Balasubramanian

A novel approach, Multipeak mean based optimized histogram modification framework (MMOHM) is introduced for the purpose of enhancing the contrast as well as preserving essential details for any given gray scale and colour images. The basic idea of this technique is the calculation of multiple peaks (local maxima) from the original histogram. The mean value of multiple peaks is computed and the input image’s histogram is segmented into two subhistograms based on this multipeak mean (mmean) value. Then, a bicriteria optimization problem is formulated and the subhistograms are modified by selecting optimal contrast enhancement parameters. While formulating the enhancement parameters, particle swarm optimization is employed to find optimal values of them. Finally, the union of the modified subhistograms produces a contrast enhanced and details preserved output image. This mechanism enhances the contrast of the input image better than the existing contemporary HE methods. The performance of the proposed method is well supported by the contrast enhancement quantitative metrics such as discrete entropy, natural image quality evaluator, and absolute mean brightness error.


Blood ◽  
1987 ◽  
Vol 69 (5) ◽  
pp. 1469-1474 ◽  
Author(s):  
E Murphy ◽  
LR Berkowitz ◽  
E Orringer ◽  
L Levy ◽  
SA Gabel ◽  
...  

Abstract In this study, we used a recently developed nuclear magnetic resonance (NMR) technique to measure ionized calcium in sickle erythrocytes. The NMR technique, which involves 19F NMR studies of a fluorinated calcium chelator quinMF, [2-(2-amino-4-methyl-5-fluorophenoxy)methyl-8- aminoquinoline-N,N,N′,N′- tetraacetic acid] provides a novel approach to the study of ionized calcium in erythrocytes since the presence of hemoglobin precludes the use of fluorescent calcium indicators. The mean value for ionized calcium in oxygenated sickle erythrocytes was 18 +/- 2 nmol/L (SE). Experiments with normal RBCs gave a mean value of 21 +/- 2 nmol/L (SE). After 1 hour of deoxygenation, mean values for ionized calcium in sickle erythrocytes did not increase as compared with values obtained under oxygen. To investigate whether deoxygenation stimulated endocytosis, sickle erythrocytes were deoxygenated for 1 hour in the presence of impermeant FBAPTA (1,2 bis-(2-amino-5- fluorophenoxy) ethane N,N,N′,N′-tetraacetic acid). Cells were then separated from the extracellular medium and assayed for the presence of FBAPTA; they had incorporated significant quantities of the extracellular FBAPTA. This incorporation was not observed with normal erythrocytes. These data are consistent with at least a portion of the elevation in total cell calcium in sickle erythrocytes arising as a consequence of an endocytotic process in which extracellular calcium ions are incorporated into vesicles. Additional experiments show that these intracellular vesicles accumulate Ca2+ on further deoxygenation, consistent with a transient increase in ionized cell calcium. These studies represent the first use of NMR spectroscopy to evaluate endocytotic processes.


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