Myeloid Sarcoma of the Skin in a Patient with Myelodysplastic Syndrome

ABSTRACT We report the case of a 76-year-old woman who presented with asymptomatic extensive erythematous. Firm plaques were noted over the right cheek. Complete blood count was normal, as was a peripheral smear. An excision biopsy taken from the cheek showed infiltration of the dermis and hypodermis with atypical cells which were strongly positive for human leukocyte antigen (HLA-DR) and lysozyme and were moderately myeloperoxidase (MPO) enzyme. The results of immunohistochemical staining for CD34, CD117, CD3, CD4, CD8, CD20, CD23, CD56, and ALK-1 were negative. Bone marrow analysis indicated myelodysplastic syndrome RAEB 1 while cytogenetic finding showed tetrasomy 8. It was recommended that the patient undergo local radiotherapy of skin lesions, but she refused and was lost to follow-up. KEY WORDS: skin; myeloid sarcoma; myelodysplastic syndrome </p

Geometric Constellation Shaping for Fiber-Optic Channels via End-to-End Learning

End-to-end learning has become a popular method to optimize a constellation shape of a communication system. When the channel model is differentiable, end-to-end learning can be applied with conventional backpropagation algorithm for optimization of the shape. A variety of optimization algorithms have also been developed for end-to-end learning over a non-differentiable channel model. In this paper, we compare gradient-free optimization method based on the cubature Kalman filter, model-free optimization and backpropagation for end-to-end learning on a fiber-optic channel modeled by the split-step Fourier method. The results indicate that the gradient-free optimization algorithms provide a decent replacement to backpropagation in terms of performance at the expense of computational complexity. Furthermore, the quantization problem of finite bit resolution of the digital-to-analog and analog-to-digital converters is addressed and its impact on geometrically shaped constellations is analysed. Here, the results show that when optimizing a constellation with respect to mutual information, a minimum number of quantization levels is required to achieve shaping gain. For generalized mutual information, the gain is maintained throughout all of the considered quantization levels. Also, the results implied that the autoencoder can adapt the constellation size to the given channel conditions

End-to-end Learning of a Constellation Shape Robust to Channel Condition Uncertainties

Vendor interoperability is one of the desired future characteristics of optical networks. This means that the transmission system needs to support a variety of hardware with different components, leading to system uncertainties throughout the network. For example, uncertainties in signal-to-noise ratio and laser linewidth can negatively affect the quality of transmission within an optical network due to e.g. mis-parametrization of the transceiver signal processing algorithms. In this paper, we propose to geometrically optimize a constellation shape that is robust to uncertainties in the channel conditions by utilizing end-to-end learning. In the optimization step, the channel model includes additive noise and residual phase noise. In the testing step, the channel model consists of laser phase noise, additive noise and blind phase search as the carrier phase recovery algorithm. Two noise models are considered for the additive noise: white Gaussian noise and nonlinear interference noise model for fiber nonlinearities. The latter models the behavior of an optical fiber channel more accurately because it considers the nonlinear effects of the optical fiber. For this model, the uncertainty in the signal-to-noise ratio can be divided between amplifier noise figures and launch power variations. For both noise models, our results indicate that the learned constellations are more robust to uncertainties in channel conditions compared to a standard constellation scheme such as quadrature amplitude modulation and standard geometric constellation shaping techniques

Gradient-free training of autoencoders for non-differentiable communication channels

Training of autoencoders using the back-propagation algorithm is challenging for non-differential channel models or in an experimental environment where gradients cannot be computed. In this paper, we study a gradient-free training method based on the cubature Kalman filter. To numerically validate the method, the autoencoder is employed to perform geometric constellation shaping on differentiable communication channels, showing the same performance as the back-propagation algorithm. Further investigation is done on a non-differentiable communication channel that includes: laser phase noise, additive white Gaussian noise and blind phase search-based phase noise compensation. Our results indicate that the autoencoder can be successfully optimized using the proposed training method to achieve better robustness to residual phase noise with respect to standard constellation schemes such as Quadrature Amplitude Modulation and Iterative Polar Modulation for the considered conditions

BICM-compatible Rate Adaptive Geometric Constellation Shaping Using Optimized Many-to-one Labeling

In this paper, a rate adaptive geometric constellation shaping (GCS) scheme which is fully backward-compatible with existing state of the art bit-interleaved coded modulation (BICM) systems is proposed and experimentally demonstrated. The system relies on optimization of the positions of the quadrature amplitude modulation (QAM) points on the I/Q plane for maximized achievable information rate, while maintaining quantization and fiber nonlinear noise robustness. Furthermore, `dummy' bits are multiplexed with coded bits before mapping to symbols. Rate adaptivity is achieved by tuning the ratio of coded and `dummy' bits, while maintaining a fixed forward error-correction block and a fixed modulation format size. The points' positions and their labeling are optimized using automatic differentiation. The proposed GCS scheme is compared to a time-sharing hybrid (TH) QAM modulation and the now mainstream probabilistic amplitude shaping (PAS) scheme. The TH without shaping is outperformed for all studied data rates in a simulated linear channel by up to 0.7 dB. In a linear channel, PAS is shown to outperform the proposed GCS scheme, while similar performances are reported for PAS and the proposed GCS in a simulated nonlinear fiber channel. The GCS scheme is experimentally demonstrated in a multi-span recirculating loop coherent optical fiber transmission system with a total distance of up to 3000 km. Near-continuous zero-error flexible throughput is reported as a function of the transmission distance. Up to 1-2 spans of increased reach gains are achieved at the same net data rate w.r.t. conventional QAM. At a given distance, up to 0.79 bits/2D symbol of gain w.r.t. conventional QAM is achieved. In the experiment, similar performance to PAS is demonstrated.Comment: Submitted to Journal of Lightwave Technology as a special extended version of a 'top-scored' paper at the European Conference on Optical Communications (ECOC) 202

Addressing Data Scarcity in Optical Matrix Multiplier Modeling Using Transfer Learning

We present and experimentally evaluate using transfer learning to address experimental data scarcity when training neural network (NN) models for Mach-Zehnder interferometer mesh-based optical matrix multipliers. Our approach involves pre-training the model using synthetic data generated from a less accurate analytical model and fine-tuning with experimental data. Our investigation demonstrates that this method yields significant reductions in modeling errors compared to using an analytical model, or a standalone NN model when training data is limited. Utilizing regularization techniques and ensemble averaging, we achieve < 1 dB root-mean-square error on the matrix weights implemented by a 3x3 photonic chip while using only 25% of the available data

Expression pattern of circulating long non-coding RNA GAS5 as a novel biomarker in non-small cell lung cancer patients

Introduction: The finding that long noncoding RNAs (lncRNAs) originating from tumor cells could be found in general circulation has prompted the idea to use lncRNAs as noninvasive diagnostic biomarkers of particular diseases. In this study we explored the expression pattern of circulating GAS5..

Cross-cultural validity of the psycho-social aspects of Facebook use (PSAFU) scale

© 2022 The Authors. Published by Drustvo Psihologa Srbije. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.2298/PSI210702013JThe Psycho-Social Aspects of Facebook Use (PSAFU) scale was developed by Bodroža and Jovanović (2016) to comprehensively measure psychological and social aspects of the users’ Facebook (FB) experiences i.e. compensatory use of FB, self-presentation on FB, socializing and seeking sexual partners through FB, FB addiction, and FB profile as the virtual self. The scale was previously validated on two Serbian samples. The aim of this research was to validate the PSAFU scale cross-culturally, i.e. develop a version of the scale that would be suitable for the cross-cultural study of FB behaviors. The sample consisted of 1,632 respondents from Croatia, Italy, Iran, Serbia, and UK. Administered questionnaires consisted of the PSAFU scale (Bodroža & Jovanović, 2016), the Big Five Inventory (BFI; John et al., 1991), the Narcissistic Personality Inventory 16 (NPI-16; Ames et al., 2006), and socio-demographic and FB use questions (e.g., time spent on FB on a daily basis, frequency of posting and number of FB friends). After some modifications and exclusion of the virtual self scale, the results of multigroup confirmatory factor analysis show that the PSAFU scale is cross-culturally invariant and suitable for use internationally. The remaining dimensions of revised PSAFU scale (PSAFU-R) have statistically significant relationships with measured personality traits and with indicators of FB use, although considerable cross-cultural variations were obtained