140 research outputs found
End to End Deep Neural Network Frequency Demodulation of Speech Signals
Frequency modulation (FM) is a form of radio broadcasting which is widely
used nowadays and has been for almost a century. We suggest a
software-defined-radio (SDR) receiver for FM demodulation that adopts an
end-to-end learning based approach and utilizes the prior information of
transmitted speech message in the demodulation process. The receiver detects
and enhances speech from the in-phase and quadrature components of its base
band version. The new system yields high performance detection for both
acoustical disturbances, and communication channel noise and is foreseen to
out-perform the established methods for low signal to noise ratio (SNR)
conditions in both mean square error and in perceptual evaluation of speech
quality score
Rotational viscosity in ferroelectric liquid crystals estimated from transient light scattering and dielectric properties
A new method for the estimation of rotational viscosity of ferroelectric liquid crystals using transient light scattering (TSM) is reported. The relation between rotational viscosity, spontaneous polarization, and dielectric dispersion frequency is studied as a function of the racemization. The rotational viscosity is almost independent of spontaneous polarization and there is no obvious correlation between rotational viscosity and dispersion frequency. The dispersion frequency is confirmed to be inversely proportional to the square of the helical pitch. The rotational viscosity calculated from this relation is consistent with that from the new TSM method.This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in M. Ozaki, T. Hatai, K. Nakao, and K. Yoshino, Journal of Applied Physics 65, 3602 (1989) and may be found at https://doi.org/10.1063/1.342639
INDONESIAN HATCHERY REARED SEABASS LARVAE (Lates calcarifer), ASSOCIATED WITH VIRAL NERVOUS NECROSIS (VNN)
Mass tuortality atuongs seabass larvae, Lates calcarifer, reared in hatcheries in East and Bali due to viral nervous necrosis were investigated. outbreaks of the disease occured from August to Novetnber 1997
Modification of Collagen by 3-Deoxyglucosone Alters Wound Healing through Differential Regulation of p38 MAP Kinase
Background: Wound healing is a highly dynamic process that requires signaling from the extracellular matrix to the fibroblasts for migration and proliferation, and closure of the wound. This rate of wound closure is impaired in diabetes, which may be due to the increased levels of the precursor for advanced glycation end products, 3-deoxyglucosone (3DG). Previous studies suggest a differential role for p38 mitogen-activated kinase (MAPK) during wound healing; whereby, p38 MAPK acts as a growth kinase during normal wound healing, but acts as a stress kinase during diabetic wound repair. Therefore, we investigated the signaling cross-talk by which p38 MAPK mediates wound healing in fibroblasts cultured on native collagen and 3DG-collagen. Methodology/Principal Findings: Using human dermal fibroblasts cultured on 3DG-collagen as a model of diabetic wounds, we demonstrated that p38 MAPK can promote either cell growth or cell death, and this was dependent on the activation of AKT and ERK1/2. Wound closure on native collagen was dependent on p38 MAPK phosphorylation of AKT and ERK1/2. Furthermore, proliferation and collagen production in fibroblasts cultured on native collagen was dependent on p38 MAPK regulation of AKT and ERK1/2. In contrast, 3DG-collagen decreased fibroblast migration, proliferation, and collagen expression through ERK1/2 and AKT downregulation via p38 MAPK. Conclusions/Significance: Taken together, the present study shows that p38 MAPK is a key signaling molecule that plays
A visceral mycosis in ayu fry, Plecoglossus altivelis Temminck & Schlegel, caused by a species of Phoma
Inhibitory Effect of Buah Merah Oil on Melanogenesis Via Degradation of Tyrosinase
Buah Merah (Pandanus conoideus) is exclusively distributed in Papua island and its neighboring areas. The extract oil from fruits (Buah Merah oil) contains rich in lipids, carotenoids and vitamin E.We assessed the effects of Buah Merah oil on melanogenesis in B16 melanoma cells. In the presence of alpha-melanocyte stimulating hormone (α-MSH), B16 melanoma cells are stimulated to enhance melanin synthesis. Buah Merah oil inhibited α-MSH-induced melanin synthesis with no cytotoxicity. This decrease in melanogenesis was correlated with reduced enzyme activity and decreased protein expression levels of tyrosinase. Tyrosinase is a type 1 membrane glycoprotein that is the critical rate-limiting enzyme involved in melanin synthesis. Furthermore, the Buah Merah oil-induced decrease in melanin content was accompanied by a decrease in the amount and activity of tyrosinase whereas the mRNA level of tyrosinase was unchanged. Moreover, treatment with proteasome inhibitor MG132 blocked the down-regulation of melanogenesis by Buah Merah oil. Immunoprecipitation analysis also revealed that treatment with Buah Merah oil modulated the ubiquitination of tyrosinase, that is Buah Merah oil increased the amount of ubiquitinated tyrosinase.Taken together, the present results indicate that the depigmenting effect of Buah Merah oil might be due to inhibition of tyrosinase expression through the ubiquitin proteasome-mediated degradation of tyrosinase
Studies on the pathogenesis of streptococcal infection in cultured yellowtails Seriola spp.: effect of the cell free culture on experimental streptococcal infection
Relationship between the splicing pattern of the Drosophila sodium channel gene and the phenotypic variety
- …