3,500 research outputs found

    Novel extra-thoracic VATS minimally invasive technique for management of multiple rib fractures.

    Get PDF
    We report an elderly patient with chronic obstructive pulmonary disease (COPD), Alzheimer\u27s disease and early dementia who presented with multiple displaced rib fractures of left ribs 4 through 9 with flail segments of ribs 4 through 8 and an associated traumatic pneumatocele from rib puncture of the left upper lobe. The decision to treat this patient operatively was based on the presence of flail chest, the patient\u27s age, baseline co-morbidities and limited physiological reserve. Surgical rib fixation is traditionally performed with a thoracotomy incision and open exposure for extra-thoracic rib fixation, however, this patient underwent chest wall stabilization using an extra-thoracic video-assisted thoracic surgery (VATS) technique. We discuss our operative technique using universal rib plating system, optimal retraction for exposure and use of balloon dilation to create an accessible extra-thoracic working space. This surgical approach provided a faster recovery to this patient\u27s baseline with minimal use of narcotics thereby highlighting the impact and importance of this surgical technique for patients presenting with multiple fib fractures, especially the elderly. We show that VATS assisted minimally invasive technique for operative management of multiple rib fractures is a viable surgical option demonstrated by this patient\u27s recovery and return to function with minimal need for pain control despite her advanced age and baseline co-morbidities

    An efficient adaptive fusion scheme for multifocus images in wavelet domain using statistical properties of neighborhood

    Get PDF
    In this paper we present a novel fusion rule which can efficiently fuse multifocus images in wavelet domain by taking weighted average of pixels. The weights are adaptively decided using the statistical properties of the neighborhood. The main idea is that the eigen value of unbiased estimate of the covariance matrix of an image block depends on the strength of edges in the block and thus makes a good choice for weight to be given to the pixel, giving more weightage to pixel with sharper neighborhood. The performance of the proposed method have been extensively tested on several pairs of multifocus images and also compared quantitatively with various existing methods with the help of well known parameters including Petrovic and Xydeas image fusion metric. Experimental results show that performance evaluation based on entropy, gradient, contrast or deviation, the criteria widely used for fusion analysis, may not be enough. This work demonstrates that in some cases, these evaluation criteria are not consistent with the ground truth. It also demonstrates that Petrovic and Xydeas image fusion metric is a more appropriate criterion, as it is in correlation with ground truth as well as visual quality in all the tested fused images. The proposed novel fusion rule significantly improves contrast information while preserving edge information. The major achievement of the work is that it significantly increases the quality of the fused image, both visually and in terms of quantitative parameters, especially sharpness with minimum fusion artifacts

    Human-mobility-based sensor context-aware routing protocol for delay-tolerant data gathering in multi-sink cell-phone-based sensor networks

    Get PDF
    Ubiquitous use of cell phones encourages development of novel applications with sensors embedded in cell phones. The collection of information generated by these devices is a challenging task considering volatile topologies and energy-based scarce resources. Further, the data delivery to the sink is delay tolerant. Mobility of cell phones is opportunistically exploited for forwarding sensor generated data towards the sink. Human mobility model shows truncated power law distribution of flight length, pause time, and intercontact time. The power law behavior of inter-contact time often discourages routing of data using naive forwarding schemes. This work exploits the flight length and the pause time distributions of human mobility to design a better and efficient routing strategy. We propose a Human-Mobility-based Sensor Context-Aware Routing protocol (HMSCAR), which exploits human mobility patterns to smartly forward data towards the sink basically comprised of wi-fi hot spots or cellular base stations. The simulation results show that HMSCAR significantly outperforms the SCAR, SFR, and GRAD-MOB on the aspects of delivery ratio and time delay. A multi-sink scenario and single-copy replication scheme is assumed

    Chip equalized adaptive rake receiver for DS-CDMA UWB systems

    Get PDF
    Conventional Rake receiver is a popular and effective method of utilizing the diversity offered by a DS-CDMA and multipath communication channel. The proposed Rake receiver is useful for suppression of multiple access interference in a multipath channel. The receiver works on chip level equalization on each Rake finger to cancel multi-access interference. Simulation results show that the convergence, diversity gain and bit error probability performance of the proposed receiver is much better than conventional adaptive Rake receiver in multipath channels
    corecore