Acoustic Echo and Noise Cancellation System for Hand-Free Telecommunication using Variable Step Size Algorithms

In this paper, acoustic echo cancellation with doubletalk detection system is implemented for a hand-free telecommunication system using Matlab. Here adaptive noise canceller with blind source separation (ANC-BSS) system is proposed to remove both background noise and far-end speaker echo signal in presence of double-talk. During the absence of double-talk, far-end speaker echo signal is cancelled by adaptive echo canceller. Both adaptive noise canceller and adaptive echo canceller are implemented using LMS, NLMS, VSLMS and VSNLMS algorithms. The normalized cross-correlation method is used for double-talk detection. VSNLMS has shown its superiority over all other algorithms both for double-talk and in absence of double-talk. During the absence of double-talk it shows its superiority in terms of increment in ERLE and decrement in misalignment. In presence of double-talk, it shows improvement in SNR of near-end speaker signal

Cancer Epigenomics: a review

Epigenetic inactivation of genes that are crucial for the control of normalcell growth is a hallmark of cancer cells. Epigenetic modifications of the DNA do not alter the nucleotide sequence instead they involve the regulation of gene transcription and DNA methylation. Hypermethylation or histone deacetylation, which is within the promoter of a tumor suppressor gene, leads to the silencing as well as a deletion or a mutation of thatgene. Cancer cells often show aberrant methylation and the frequency of aberrations increases is seen with the progression of disease. Hypermethylation events can occur early in tumorogenesis, involving the disruption of pathways that may predispose cells to malignant transformation. Epigenetic modification such as DNA methylation can be exploited for clinical purposes in cancer patients, first using hypermethylation as a molecular biomarker of cancer cells and second, epigenetic changes which are potentially reversible

Modular relations involving generalized digamma functions

Generalized digamma functions $\psi_k(x)$, studied by Ramanujan, Deninger, Dilcher, Kanemitsu, Ishibashi etc., appear as the Laurent series coefficients of the zeta function associated to an indefinite quadratic form. In this paper, a modular relation of the form $F_k(\alpha)=F_k(1/\alpha)$ containing infinite series of $\psi_k(x)$, or, equivalently, between the generalized Stieltjes constants $\gamma_k(x)$, is obtained for any $k\in\mathbb{N}$. When $k=0$, it reduces to a famous transformation given on page $220$ of Ramanujan's Lost Notebook. For $k=1$, an integral containing Riemann's $\Xi$-function, and corresponding to the aforementioned modular relation, is also obtained along with its asymptotic expansions as $\alpha\to0$ and $\alpha\to\infty$. Carlitz-type and Guinand-type finite modular relations involving $\psi_j^{(m)}(x), 0\leq j\leq k, m\in\mathbb{N}\cup\{0\},$ are also derived, thereby extending previous results on the digamma function $\psi(x)$. The extension of Guinand's result for $\psi_j^{(m)}(x), m\geq2,$ involves an interesting combinatorial sum $h(r)$ over integer partitions of $2r$ into exactly $r$ parts. This sum plays a crucial role in an inversion formula needed for this extension. This formula has connection with the inversion formula for the inverse of a triangular Toeplitz matrix. The modular relation for $\psi_j'(x)$ is subtle and requires delicate analysis.Comment: 32 pages, submitted for publication; comments are welcome. Corrected the funding information in the first versio

A study on greater trochanter reconstruction in unstable inter trochanteric fracture of femur

Background: A study on greater trochanter reconstruction in unstable intertrochanteric femur fracture. Methods: The 2019 to 2022, Patients were randomly divided into two groups with the help of computer-generated coded envelopes; Group A (unstable intertrochanteric femur fracture patients treated by hemi-arthroplasty or PFN with greater trochanter reconstruction) and Group B (unstable intertrochanteric femur fracture Patients Treated by hemi-arthroplasty or PFN with no greater trochanter reconstruction) with 20 patients in each group Outcomes were evaluated based on Harris hip score calculated at 2 weeks 6 weeks 3 months and 6 months. Results: Most common surgery in study groups performed were PFN, on radiology as non-union and union, most common study participants show union, on follow up at 2,6 weeks,3 months and 6 months Harris hip score was calculated and it was found to be statistically significant suggestive of improved quality of life, on radiological evaluation all cases shows non-displacement of GT position but in follow-ups at 6 weeks, 3 months and 6 months one case each reported displaced implant. Conclusions: The result of our study shows that there is improved quality of life and significant improvement in Harris hip score after reconstruction of greater trochanter in unstable intertrochanteric femur fracture

Antiretroviral therapy timing impacts latent tuberculosis infection reactivation in a Mycobacterium tuberculosis/SIV coinfection model

Studies using the nonhuman primate model of Mycobacterium tuberculosis/simian immunodeficiency virus coinfection have revealed protective CD4+ T cell-independent immune responses that suppress latent tuberculosis infection (LTBI) reactivation. In particular, chronic immune activation rather than the mere depletion of CD4+ T cells correlates with reactivation due to SIV coinfection. Here, we administered combinatorial antiretroviral therapy (cART) 2 weeks after SIV coinfection to study whether restoration of CD4+ T cell immunity occurred more broadly, and whether this prevented reactivation of LTBI compared to cART initiated 4 weeks after SIV. Earlier initiation of cART enhanced survival, led to better control of viral replication, and reduced immune activation in the periphery and lung vasculature, thereby reducing the rate of SIV-induced reactivation. We observed robust CD8+ T effector memory responses and significantly reduced macrophage turnover in the lung tissue. However, skewed CD4+ T effector memory responses persisted and new TB lesions formed after SIV coinfection. Thus, reactivation of LTBI is governed by very early events of SIV infection. Timing of cART is critical in mitigating chronic immune activation. The potential novelty of these findings mainly relates to the development of a robust animal model of human M. tuberculosis/HIV coinfection that allows the testing of underlying mechanisms