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Polarimetric Synthetic Aperture Radar (PolSAR) imaging extended SAR applications by exploring the polarimetric properties of the target scatterers. Similar to SAR images, PolSAR images are prone to multiplicative speckle noise due to its coherent imaging mechanism. Hence, despeckling is an essential procedure for effectively utilizing the PolSAR images for remote sensing applications. Latest advances in PolSAR filtering techniques have shown the trend of using spatial domain techniques based on multiplicative speckle noise model which impairs the retrieved image by oversmoothing and absence of image finer details. More efficient despeckling algorithm using bandelet thresholding is proposed in this paper. Since the bandelet transform is computationally expensive, a spatially adaptive technique using directional variance is proposed. Performance evaluation with both airborne and spaceborne radar images has shown the approached technique is much efficient related to speckle reduction and feature preservation compared to the state of art techniques.

The mean length of stay was 8.7 days (range 5-27). There was no mortality. The main complication was wound infection, seen in six of the 10 patients who had their wounds closed primarily. Discussion Previous authors have reported that animals such as the camel and donkey can inflict serious injuries. 6-8 We have shown that cattle are also responsible for injury to handlers and bystanders. These injuries are commonly from the long-horned cows 1,6 (Figure 1), which usually attack their victims on provocation while grazing. Bystanders may also be attacked, especially from the rear by a cow that is being pulled by handlers. The patients in this study were all attacked by longhorned cows, sustaining injuries in various parts of the body, most commonly the abdomen. The cows usually attack by lifting and throwing down the victim with tremendous force. 5 The cow, like the camel, may occasionally kick its victim. 8 Serious injuries may occur in addition to the injuries caused by the cow horns when victims are thrown to the ground. All but two of the patients were men. This is not surprising, because cattle rearing is predominantly done by men, like most other outdoor occupations in our environment. The patients were managed depending on the nature of their injuries, with laparotomy if clinically indicated. All patients had wound debridement. Some had primary closure of the wounds, and our results show that these cases have a high infection rate. These injuries may be reduced by proper handling of the cattle, with legislation to enforce transporting them by vehicle, rather than pulling them along the road. Also recommended are the wearing of protective gears, such as helmets and corsets, coagulation of the horns after a calf's birth and disbudding and dehorning of the animals. Health education may help in achieving this. 2,5,6 Conclusion There is significant risk of sustaining injury, often severe, from cattle rearing. A combination of education and legislation promoting protective measures may decrease the incidence of these injuries. References

Polarimetric Synthetic Aperture Radar is being used widely in order to extract the features of target image including civilian and military applications. Edge detection in PolSAR images is highly challenging task due to the occurrence of speckle noise in these images although widely used for the strategic applications. This paper presents a multi-resolution edge detection method for PolSAR images using the bandelet transform. Bandelet transform can provide flexible multiscale and directional decomposition of images including SAR images. Edge enhancement of the input image is done after decomposing it using bandelet transform and the resultant bandelet coefficients are modified through the maximisation of the polarimetric contrast between the adjacent subbands using Lagrangian methods. Taking advantage of the directional features of bandelet transform an algorithm is developed for retaining the geometrical features of images such as edges, boundaries etc present in SAR images while ensuring effective speckle noise removal. Here the geometrical features in images are enhanced in the bandelet domain by fusing the different directional subband coefficients at different scales. The performance of this method is verified using real PolSAR images. The result shows that proposed scheme eliminates speckle noise and retrieved edges are continuous and complete.

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