74 research outputs found
A contest of sensors in close range 3D imaging: performance evaluation with a new metric test object
An independent means of 3D image quality assessment is introduced, addressing non-professional users of sensors and freeware, which is largely characterized as closed-sourced and by the absence of quality metrics for processing steps, such as alignment. A performance evaluation of commercially available, state-of-the-art close range 3D imaging technologies is demonstrated with the help of a newly developed Portable Metric Test Artefact. The use of this test object provides quality control by a quantitative assessment of 3D imaging sensors. It will enable users to give precise specifications which spatial resolution and geometry recording they expect as outcome from their 3D digitizing process. This will lead to the creation of high-quality 3D digital surrogates and 3D digital assets. The paper is presented in the form of a competition of teams, and a possible winner will emerge
Cellular energy allocation of pistachio green stink bug, Brachynema germari Kol. (Hemiptera.: Pentatomidae) in relation to juvenoid pyriproxyfen
The purpose of this study is to determine the effects of pyriproxyfen (an insect growth regulator compound) on cellular energy allocation of a heterometabolous insect, Brachynema germari Kol. The fifth instar of this insect was treated with 0, 20, 60, 100, 200 and 500 mg l-1 formulation of pyriproxyfen (Admiral 10EC) and the amount of energy available (Ea), energy consumption (Ec) and cellular energy allocation (CEA) were compared. The resulting calculated energy reserves (carbohydrate, glycogen, lipid and protein) showed that total lipid amount varied significantly among doses and between each dose and control. Lipid amounts fell as doses grew to 200 mg l-1 and then increased. A significant difference was observed in total carbohydrate between each dose and control (P < 0.05); however there were no significant differences among doses. The amount of glycogen and total protein and also the amount of energy consumption did not differ significantly from control. Study results showed that pyriproxyfen at low concentrations, raised cellular energy allocation but decreased it at high concentrations.Keywords: Pyriproxyfen, Brachynema germari, cellular energy allocation, lipid, glycogen, proteinAfrican Journal of Biotechnology Vol. 9(35), pp. 5746-5753, 30 August, 201
Digestive Proteolytic Activity in the Sunn Pest, Eurygaster integriceps
The Sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutelleridae), is one of the most important pests of wheat and causes considerable damage to this valuable crop annually. Digestive proteinase activity of adult insects was investigated using general and specific substrates and inhibitors. Proteolytic activity was low when the common conventional substrates, azoalbumin, azocasein and hemoglobin were used to assay salivary glands and midguts. Using the fluorescent casein substrate (BODIPY FL casein), total proteolytic activity was measured at different pH. Maximum proteolytic activity was detected at pH 7 (100%) and 8(65%) which suggested the presence of serine proteinases in the salivary glands. There was no detectable proteolytic activity in midgut extracts. The inhibitors; PMSF (inhibitor of serine proteinases) and TPCK (a specific chymotrypsin inhibitor) showed greater than 50% inhibitory effect on total proteolytic activity, however, TLCK (specific trypsin inhibitor) and E-64(specific cysteine proteinase inhibitor) did not inhibit total proteolytic activity. Using fluorescent specific substrates for serine and cysteine proteinases (Z-Arg-AMC, Z-Arg-Arg-AMC, Z-Arg-Phe-AMC and Suc-Ala-Ala-Pro-Phe-AMZ) revealed the presence of tryptic and chymotryptic activity in the salivary gland extract. Zymogram analysis under non-reducing SDS-PAGE conditions and using the substrate APNE showed at least 8 tryptic and chymotryptic activity bands in salivary gland extracts. A single high molecular weight band with tryptic activity (165 kDa) was detected using the substrate BApNA in a zymogram analysis uisng native-PAGE. Kinetic studies showed a km value of 0.6 mM for this enzyme against the substrate BApNA .The inhibitor TLCK decreased activity of the trypsin-like enzyme up to 73% and almost completely eliminated the only band related to this proteinase in the zymogram. Soybean Kunitz type trypsin inhibitor showed no effect on proteolytic activity of the trypsin-like serine proteinase. In general, the results revealed the presence of chymotrypsin- and trypsin-like serine proteinases in the salivary gland of E. integriceps, and it seems that the major total proteolytic activity is due to chymotrypsin proteinases
Automatic Image Selection in Photogrammetric Multi-view Stereo Methods
This paper brings together a team of specialists in optical metrology, museum curation, collection digitization and 3D development to describe and illustrate by example a method for the selection of the most suitable camera views, vantage viewpoints, from a large image dataset intended for metric 3D artefact reconstruction. The presented approach is capable of automatically identifying and processing the most appropriate images from a multi-image photogrammetric network captured by an imaging specialist. The aim is to produce a 3D model suited to a wide range of museum uses, including visitor interactives. The approach combines off-the-shelf imaging equipment with rigorous photogrammetric bundle adjustment and multi-view stereo (MVS), supported by an image selection process that is able to take into account range-related and visibility-related constraints. The paper focusses on the two key steps of image clustering and iterative image selection. The developed method is illustrated by the 3D recording of four ancient Egyptian artefacts from the Petrie Museum of Egyptian Archaeology at UCL, with an analysis taking into account completeness, coordination uncertainty and required number of images. Comparison is made against the baseline of the established CMVS (Clustering Views for Multi-view Stereo), which is a free package for selecting vantage images within a huge image collection. For the museum, key outputs from the 3D recording process are visitor interactives which are built around high quality textured mesh models. The paper therefore considers the quality of the output from each process as input to texture model generation. Results demonstrate that whilst both methods can provide high quality records, our new method, Image Network Designer (IND), can provide a better image selection for MVS than CMVS in terms of coordination uncertainty and completeness of the final model for the museum recording of artefacts. Furthermore, the improvements gained, particularly in model completeness, minimise the significant overhead in mesh editing needed to provide a more direct and economical route to 3D model output
Biochemical properties of digestive carbohydrases from the sugar beet weevil, Lixus incanescens (Coleoptera: Curculionidae)
The sugar beet weevil, Lixus incanescens B., is one of the most important pests of sugar beet plant in Iran. The petioles and leaves of sugar beet are attacked by larvae and adults of the sugar beet weevil. Chemical application is currently used for controlling the pest. Digestion in the alimentary canal of the sugar beet weevil is facilitated by some carbohydrases. Results of the in vitro studies indicated the presence of alpha-amylase, beta-glucosidase and beta-galactosidase in the digestive tract of the pest. Highest activities of alpha-amylase, beta-glucosidase and beta-galactosidase were at pH 5, pH 5 and pH 4, respectively. No significant alpha-glucosidase and alpha-galactosidase activity was detected in the pest's digestive system. Optimum temperatures for alpha-amylase, beta-glucosidase and beta-galactosidase activity were determined at 45, 50 and 40 oC, respectively. alpha-amylase was more stable under acidic condition (pH 4 to pH 6) than under highly acidic and alkaline condition. Na+ and K+ increased alpha-amylase activity, but sodium dodecyl sulfate significantly decreased amylase activity. Also, the activity of alpha-amylase was inhibited by the other compounds such as MgCl2, CaCl2 and EDTA. Zymogram analysis using native-PAGE revealed one band of alpha-amylase activity in Lixus incanescens. High activity of carbohydrases in the digestive system of adults was determined and further researches are needed to be applied to design new strategies for controlling the sugar beet weevil based on natural carbohydrase inhibitors
Life table parameters of the cotton bollworm, Helicoverpa armigera (Lep.: Noctuidae) on different soybean cultivars
Influence of 13 soybean cultivars (356, M4, M7, M9, Clark, Sahar, JK, BP, Williams, L17, Zane, Gorgan3 and DPX) on the life table parameters of the cotton bollworm, Helicoverpa armigera (Hübner) was studied at 25 ± 1°C, relative humidity of 65 ± 5% and a photoperiod of 16: 8 (L: D) h. The survival rate (lx) of individuals developed to adults from the initial cohort on the mentioned cultivars was estimated 0.87, 0.83, 0.96, 0.96, 0.77, 0.72, 0.81, 0.72, 0.85, 0.74, 0.85, 0.88 and 0.72, respectively. The longest and shortest life expectancy (ex) of the pest was 44.22 and 35.98 days on Gorgan3 and BP, respectively at the beginning of life. The intrinsic rate of natural increase (rm) on different cultivars ranged from 0.1324 to 0.1848 (day -1), which was lowest on 356 and highest on M9. The highest net reproductive rate (R0) was on M7 (354.92 female/female/generation) and the lowest value of this parameter was on 356 (89.35). The values of finite rate of increase (λ), mean generation time (T) and doubling time (DT) on different soybean cultivars were as follows: 1.14 to 1.20 female offspring per female per day for λ, 28.85 to 36.61 days for T and 3.75 to 5.23 days for DT. Because of the higher coefficient of determination (R2) value in Gompertz model, data from different cultivars had a better fit to this model compared with Weibull model. The results indicated that 356, L17, Gorgan3, BP and Sahar cultivars were less suitable host plants, suggesting that they are more resistant to H. armigera than the other cultivars
Nutritional Indices of the Cotton Bollworm, Helicoverpa armigera, on 13 Soybean Varieties
The effects of 13 soybean varieties (356, M4, M7, M9, Clark, Sahar, JK, BP, Williams, L17, Zane, Gorgan3, and DPX) on nutritional indices of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), were determined at 25 ± 1° C, 65 ± 5% RH and a photoperiod of 16:8 L:D. Fourth instar larvae reared on Zane showed the highest efficiency of conversion of digested food (ECD) and approximate digestibility (AD) values (0.299 and 0.867, respectively) compared with other varieties. The lowest value of ECD and food consumed (FC) was on 356 (0.133 and 53.82 mg, respectively). The highest and lowest efficiency of conversion of ingested food (ECI) of fifth instar larvae (0.235 and 0.156, respectively) were on Zane and M4, respectively. The ECI and ECD values of whole larval instars were the highest on M7 (0.524 and 0.820, respectively) and lowest on Sahar (0.279 and 0.353, respectively). However, the highest and lowest value of consumption index (CI) was on M7 (7.351) and BP (3.462). Among the different varieties of soybean, the highest AD value was on M9 (0.858), and the lowest was on Zane (0.597). The results indicated that M4, Sahar, and JK were partially resistant to H. armigera
- …