An MRI brain disease classification system using PDFB-CT and GLCM with kernel-SVM for medical decision support

Multimedia Tools and Applications - The automatic binary classification of normal and abnormal subjects using magnetic resonance (MR) brain images has made remarkable progress in recent years. This...     

Benchmarking of lightweight cryptographic algorithms for wireless IoT networks

Wireless Networks - Cryptographic algorithms that can provide both encryption and authentication are increasingly required in modern security architectures and protocols (e.g. TLS v1.3). Many...     

Resection as elective treatment of hilar cholangiocarcinoma (Klatskin tumor)

A retrospective analysis of our experience in the treatment of hiliary cholangiocarcinoma or Klatskin tumor was performed with the aim of evaluating the morbi-mortality and prognosis of its treatment to thereby determine the usefulness of the different therapeutic options. From 1989 to 1997, 51 patients diagnosed with hiliary cholangiocarcinoma were treated in our hospital. Surgery was indicated in 16 with curative aims (group I) while palliative treatment with percutaneous biliary drainage was indicated in 35 (group II). Biliary resection was carried out in 8 patients being associated with hepatic resection in 4 (group IA) and in 8 patients undergoing liver transplantation (group IB). Clinico-epidemiologic data and hospital stay were similar in all the groups. The frequency of complications was similar in groups I and II although the frequency of cholangitis (49%) in group II was noticeable. The percentage of readmissions was also greater in group II (12 vs 46%, respectively; p = 0.03) with prosthesis obstruction being the most frequent cause. Accumulated survival at 1, 2, and 3 years in group I was 84, 64 and 48% with a median survival of 33 months, while in group II the median survival was of 6 months with no patient surviving more than 2 years (p = 0.0001). When groups IA and IB were compared, greater frequency of complications in groups IA (100 vs 37%; p = 0.002), similar frequency of readmissions (87 vs 75%; p = NS), median survival greater in group IB (12.5 months vs 48 months) and significantly higher actuarial survival in group IB (48% in 2 years vs 83% to 2 years; p = 0.02) was observed. In conclusion, surgery is the treatment of choice in hiliary cholangiocarcinoma whenever possible, given the greater survival without a significant increase in morbimortality. Likewise, we consider that liver transplantation is a useful option in the treatment of patients with cholangiocarcinoma type IV of Bismuth.     

Results of using the recipient''s splenic artery for arterial reconstruction in liver transplantation in 23 patients

Parkinson's disease (PD) patients often develop dementia, and Alzheimer's disease (AD) patients frequently develop parkinsonian signs. The apolipoprotein E epsilon4 allele is associated with increased risk and earlier onset of AD. We studied 137 unrelated white PD patients. Those with epsilon4 had the earliest onset (52.7 +/- 9.8 years), epsilon3/epsilon3 patients had an intermediate onset (56.1 +/- 11.1 years), and those with epsilon2 had the latest onset (59.1 +/- 13.4 years). The age at onset distribution for epsilon4/epsilon- was significantly earlier than for epsilon3/epsilon3 and epsilon2/epsilon3. These preliminary results suggest that apolipoprotein E genotypes modulate the age at onset of PD.     

Petri net-based engine for adaptive learning

In this paper, an IMS LD engine based on a Petri net model that represents the operational semantics of units of learning based on this specification is presented. The Petri nets of this engine, which is called OPENET4LD, verify the structural properties that are desirable for a learning flow and also facilitate the adaptation of the engine if potential changes in the IMS LD specification were proposed. Furthermore, OPENET4LD has an open and flexible architecture based on a set of ontologies that describe both the semantics of the Petri nets execution and the semantics of each learning flow component of IMS LD. Furthermore, the implementation of this architecture has been exhaustively validated with a number of UoLs that are compliant with the levels A and B of IMS LD.     

A robust digital audio watermarking scheme based on DWT and Schur decomposition

The vulnerability of digital audio signals for different types of risks requires an imperceptible and robust digital audio watermarking scheme. In this research, we propose creating one such imperceptible and robust hybrid watermarking scheme based on a discrete wavelet transform (DWT) and Schur decomposition hybrid method. The proposed scheme embeds the foreground bits of the watermarking image into the least significant bit of the diagonal coefficients of the triangular matrix S generated from Schur decomposition. Schur decomposition is applied on the second sub-band HL₂ generated from applying a second-level 2D-Haar DWT on the first channel of the original audio signal. We analyze the proposed digital audio watermarking scheme’s performance in terms of signal to noise ratio (SNR), objective difference grades (ODG), and subjective difference grades (SDG) that resulting 81.43, 4.78 and 0.184, respectively. The resulting of payload capacity, NC, and BER are as high as 319.29 bps, 0.9911, and 0.0135, respectively. Experimental results confirm that the proposed scheme is inaudible and robust against common types of attacks such as Gaussian noise, re-quantization, re-sampling, low-pass filter, high-pass filter, echo, MP3 compression, and cropping. In comparison with state-of-the-art audio watermarking schemes, the proposed scheme’s performance is superior in term of imperceptibility, robustness, and data payload size.

     

Low cost multimedia sensor networks for obtaining lighting maps

In many applications, video streams, images, audio streams and scalar data are commonly used. In these fields, one of the most important magnitudes to be collected and controlled is the light intensity in different spots. So, it is extremely important to be able to deploy a network of light sensors which are usually integrated in a more general Wireless Multimedia Sensor Network (WMSN). Light control systems have increasing applications in many places like streets, roads, buildings, theaters, etc. In these situations having a dense grid of sensing spots significantly enhances measuring precision and control performance. When a great number of measuring spots are required, the cost of the sensor becomes a very important concern. In this paper the use of very low cost light sensors is proposed and it is shown how to overcome its limited performance by directionally correcting its results. A correction factor is derived for several lighting conditions. The proposed method is firstly applied to measure light in a single spot. Additionally a prototype of a sensor network is employed to draw the lighting map of a surface. Finally the sensor grid is employed to estimate the position and power of a set of light sources in a certain region of interest (street, building, …). These three applications have shown that using low cost sensors instead of luxmeters is a feasible approach to estimate illuminance levels in a room and to derive light sources maps. The obtained error measuring spots illuminance or estimating lamp emittances are quite acceptable in many practical applications.