Speckle Noise Reduction in Medical Ultrasound Images Using Modelling of Shearlet Coefficients as a Nakagami Prior

The diagnosis of UltraSound (US) medical images is affected due to the presence of speckle noise. This noise degrades the diagnostic quality of US images by reducing small details and edges present in the image. This paper presents a novel method based on shearlet coefficients modeling of log-transformed US images. Noise-free log-transformed coefficients are modeled as Nakagami distribution and speckle noise coefficients are modeled as Gaussian distribution. Method of Log Cumulants (MoLC) and Method of Moments (MoM) are used for parameter estimation of Nakagami distribution and noise free shearlet coefficients respectively. Then noise free shearlet coefficients are obtained using Maximum a Posteriori (MaP) estimation of noisy coefficients. The experimental results were presented by performing various experiments on synthetic and real US images. Subjective and objective quality assessment of the proposed method is presented and is compared with six other existing methods. The effectiveness of the proposed method over other methods can be seen from the obtained results

BEMD Based Cross Bilateral Filtering Technique for Speckle Reduction in Ultrasound Images

In this paper, Bidimensional Empirical Mode Decomposition (BEMD) based Cross Bilateral Filter (CBF) technique for speckle reduction in ultra- sound images has been proposed. The reference image is obtained by denoising the noisy image using pixel- wise Wiener filtering. Then, both the noisy image and the reference image are decomposed into a set of In- trinsic Mode Functions (IMFs) and the residue im- age using BEMD technique. CBF is applied between noisy image IMFs and the corresponding reference im- age IMFs. The image is reconstructed back with these modified IMFs and the residue. The proposed method exploits the edge information in the reference image for improving the quality of the denoised image. The per- formance of the proposed method has been tested for real ultrasound images and simulated images having noise of different variance. The experimental results show that the proposed algorithm performs better than other state-of-art methods in terms of Edge Keeping Index (EKI), Correlation Coefficient (CC), Figure of Merit (FOM), Structural Similarity (SSIM), Peak Sig- nal to Noise Ratio (PSNR) and Signal to Noise Ratio (SNR) for synthetic images. The algorithm gives bet- ter performance for real ultrasound images in terms of Mean to Variance Ratio (MVR) and Equivalent Num- ber of Looks (ENL)

Expoldb: expression linked polymorphism database with inbuilt tools for analysis of expression and simple repeats

BACKGROUND: Quantitative variation in gene expression has been proposed to underlie phenotypic variation among human individuals. A facilitating step towards understanding the basis for gene expression variability is associating genome wide transcription patterns with potential cis modifiers of gene expression. DESCRIPTION: EXPOLDB, a novel Database, is a new effort addressing this need by providing information on gene expression levels variability across individuals, as well as the presence and features of potentially polymorphic (TG/CA)(n )repeats. EXPOLDB thus enables associating transcription levels with the presence and length of (TG/CA)(n )repeats. One of the unique features of this database is the display of expression data for 5 pairs of monozygotic twins, which allows identification of genes whose variability in expression, are influenced by non-genetic factors including environment. In addition to queries by gene name, EXPOLDB allows for queries by a pathway name. Users can also upload their list of HGNC (HUGO (The Human Genome Organisation) Gene Nomenclature Committee) symbols for interrogating expression patterns. The online application 'SimRep' can be used to find simple repeats in a given nucleotide sequence. To help illustrate primary applications, case examples of Housekeeping genes and the RUNX gene family, as well as one example of glycolytic pathway genes are provided. CONCLUSION: The uniqueness of EXPOLDB is in facilitating the association of genome wide transcription variations with the presence and type of polymorphic repeats while offering the feature for identifying genes whose expression variability are influenced by non genetic factors including environment. In addition, the database allows comprehensive querying including functional information on biochemical pathways of the human genes. EXPOLDB can be accessed a

Combination of Spatial Domain Filters for Speckle Noise Reduction in Ultrasound Medical Images

The occurrence of speckle noise in medical Ultrasound (US) images poses a big challenge to medical practitioners over last several years. Speckle noise reduces the fine details present in the images and hence make it more difficult to diagnose. In this paper, a~novel method based on the combination of three spatial domain filters is presented. The output of these filters is combined on the basis of an Intensity Classifier Map (ICF) formed using Coefficient of Dispersion (CoD) parameter. Experiments were conducted on synthetic and real US images. Quantitative and qualitative analysis of the proposed method is carried out in comparison to other six existing methods. It has been found from the obtained results that proposed method delivers observable improvement in all quantitative parameters undertaken for synthetic US image and in MVR value for real US images. Also, the effectiveness of the proposed method is found to be consistent with qualitative assessment of the denoised images

Diagnostic accuracy of MRI knee in reference to arthroscopy in meniscal and anterior cruciate ligament injuries

Objective: Data regarding the diagnostic accuracy of Magnetic Resonance Imaging (MRI) are contradictory. The aim of this study was to find the accuracy of MRI knee against arthroscopy, in cases of meniscus and Anterior Cruciate Ligament (ACL) injuries. To the best of our knowledge, this is the largest Indian study comparing MRI knee with arthroscopy comprehensively. Subjects and methods: 210 patients with knee injury who underwent both MRI knee and arthroscopy and either investigation showing ACL or meniscal tear were studied. MRI findings were correlated with arthroscopic findings, considering arthroscopy as the gold standard. Results: The sensitivity, specificity and accuracy of MRI in reference to arthroscopy for ACL tear was 97.46%, 90.38% and 95.71%, respectively; for Medial Meniscus (MM) tear was 95.69%, 94.87% and 95.23%, respectively; and for Lateral Meniscus (LM) tear was 86.04%, 97.01%, 88.09%, 96.42% and 94.76%, respectively. In ACL tear, mid substance tear was the most common site (66.03%) and discontinuity of ACL fibres was the most common pattern (42.8%). In meniscal tears, posterior horn was the most common site and vertical tears was the most common pattern. Conclusion: MRI is an excellent noninvasive imaging modality which can accurately detect and characterize various ligament tears of the knee joint. Keywords: MRI knee, Arthroscopy, ACL tear, Meniscal tea

Effect of aperture averaging and spatial diversity on capacity of optical wireless communication systems over lognormal channels

In this paper average channel capacity of optical wireless communication system with aperture averaging and diversity reception over lognormal channels is evaluated using a simple approximate closed form expression. The qualitative improvement in channel capacity is compared and investigated for various turbulence mitigation techniques: namely aperture averaging, diversity techniques such as maximal ratio combining and equal gain combining. Based on our study it has been found that aperture averaging gives reasonably improved performance as compared to both types of diversity reception beyond certain turbulence strength. However, irrespective of turbulence strength, substantial improvement in capacity may be achieved with array of direct detection receivers. Results obtained using the proposed expressions are in excellent agreement with those based on Monte Carlo simulations

Case study:Logistical behavior in the use of urban transport using the monte carlo simulation method

\u3cp\u3eThis study presents a proposal to determine solutions to the models of queue theory through the use of simulation. The main objective is to evaluate the number of people who arrive at a public transport service station in order to be able to minimize monetary losses, the product of the defection of the people of the waiting line of this station. To evaluate the model, we proceeded to use tools that allow simulating random values based on probability distributions; such as the Log-Normal probability distribution, and the Binomial distribution.\u3c/p\u3

Seasonal variation in the deformation rate in NW Himalayan region

We report GPS measurements of continuous observations from the multi-parametric geophysical observatory (MPGO) at Ghuttu, Garhwal Lesser Himalaya. Other than the evidence of secular motion depicting strain accumulation due to locking of the underneath seismically active detachment, measurements at Ghuttu show annual variation of ±4 mm on horizontal component. Such variations are more prominent in the north coordinate and do not directly correlate with the meteorological parameters such as variations in rainfall, water table, and atmospheric pressure measured at the MPGO observatory. These variations are also not the artefact of data processing and network. They correlate with the water load storage in the Ganga plains, with minimum in displacement coinciding with the maximum storage of water in Ganga plains immediately after the monsoon and vice versa. Such variations also appear to cause annual variation in the low-magnitude earthquake frequency in the Himalayan region, being relatively more in the winter period

Perceptions about training during endocrinology residency programs in India over the years: A cross-sectional study (PEER India Study)

Background: Residents' perception on quality of endocrinology training in India is not known. This study aimed to evaluate the perceptions about endocrinology residency programs in India among current trainees as compared to practicing endocrinologists. Methods: Trainees attending a preconference workshop at the annual conference of Endocrine Society of India (ESI) were given a questionnaire designed to evaluate their perceptions on their training. These evaluated the reasons for choosing endocrinology, their experiences during residency, and career plans. Practicing endocrinologists attending ESICON with at least 5-year experience were evaluated as controls. Results: Questionnaires from 63 endocrine trainees and 78 practicing endocrinologists were analyzed. Endocrinology is perceived to be the super-specialty with the best quality of life (QOL) but fair with regard to financial remuneration. Among current trainees, 61.89%, 31.74%, and 34.91% are satisfied with training in clinical endocrinology, laboratory endocrinology, and clinical/translational research, respectively. The corresponding figures for practicing endocrinologists are 71.78%, 25.63%, and 30.75%, respectively. Exposure to national endocrinology conferences during their endocrinology residency was adequate. However, exposure to international endocrinology conferences, research publications, project writing, and grant application are limited. Laboratory endocrinology is rated as the most neglected aspect during endocrine residency. Most of the trainees want to establish their own clinical practice in the long run. Very few trainees (17.46%) wish to join the medical education services. Conclusion: There is a good perception of QOL in endocrinology in spite of average financial remuneration. There is dissatisfaction with the quality of training in laboratory endocrinology and clinical research. Very few endocrine trainees consider academics as a long-term career option in India