Fast and accurate algorithm for core point detection in fingerprint images

The core point is used to align between the fingerprints in the fingerprint authentication systems faster than the conventional techniques. To speed up the processing for the real time applications, it is more convenient to implement the image processing algorithms using embedded modules that can be used in the portable systems. To do this, the algorithm should be characterized by a simple design for easier and more feasible implementation on the embedded modules. The proposed work, in this paper, presents a mask that locates the core point simply from the ridge orientation map. The introduced algorithm detects the core point at the end of the discontinuous line appearing in the orientation map presented by a gray-scale. A property is presented and supported with a mathematical proof to verify that the singular regions are located at the end of this discontinuous line. The experimental results, on the public FVC2002 and FVC2004 databases, show that the proposed mask exhibits an average increase in the correct core point detection per fingerprint by 17.35%, with a reduction in the false detection by 51.23%, compared to a fast edge-map based method. Moreover, the execution time is reduced by an average factor of 1.8

Chilling-induced oxidative stress and polyamines regulatory role in two wheat varieties

AbstractFifteen-day-old seedlings of two wheat varieties (Side 1 & Gimmiza 7) were randomly separated into three equal groups to investigate the effect of chilling stress on their antioxidant defense system. Moreover, the possible role of polyamines (PAs) pretreatment during alleviating chilling injuries. The first group was kept in a green house at 21/15°C (day/night) and 10: 14h light/dark (−ve control). Second seedlings group were chilled at 5°C for 6 or 9 hours (+ve control). The Seedlings of the third group were divided into three sub-groups and sprayed with 0.5, 1.0 and 2.0mM spermidine (Spd). After 12 hours of polyamine pre-treatments, the seedlings were incubated at 5°C for 6 or 9 hours. At the end of the chilling period, the treated plants were transferred to the pre-experimental conditions in the greenhouse where they recovered for 10 days. Chilling stress induced a significant increase of lipid peroxidation, membrane leakage and hydrogen peroxide level, while Spd treatments resulted in a significant decrease. In addition, endogenous PA level increased in response to chilling stress. Activities of catalase, peroxidase and ascorbate peroxidase declined after the exposure to chilling whereas glutathione and free ascorbate increased. Spd treatments alleviated the injury caused by chilling stress by preventing the decrease in the activity of the antioxidant enzymes. It can be concluded that the stress protection caused by spermidine treatment probably contributes to the enhancement of the activity of the free-radical scavenging systems. Moreover, it was clear that the Sids-1 cultivar was more tolerant to chilling stress than Gemmieza-7cultivar