RESUMEN
By enabling multiple non-orthogonal transmissions, power domain non-orthogonal multiple access (PD-NOMA) potentially increases a system's spectral efficiency. This technique can become an alternative for future generations of wireless communication networks. The efficiency of this method fundamentally depends on two previous processing steps: an appropriate grouping of users (transmission candidates) as a function of the channel gains and the choice of power levels that will be used to transmit each signal. Thus far, the solutions presented in the literature to address the problems of user clustering and power allocation do not consider the dynamics of communication systems, i.e., the temporal variation in the number of users and the channel conditions. In order to consider these dynamic characteristics in the clustering of users in NOMA systems, this work proposes a new clustering technique based on a modification of the DenStream evolutionary algorithm, chosen for its evolutionary capacity, noise robustness and online processing. We evaluated the performance of the proposed clustering technique considering, for simplicity, the use of an already widely known power allocation strategy called improved fractional strategy power allocation (IFSPA). The results show that the proposed clustering technique can follow the system dynamics, clustering all users and favoring the uniformity of the transmission rate between the clusters. Compared to orthogonal multiple access (OMA) systems, the proposed model's gain was approximately 10%, obtained on a challenging communication scenario for NOMA systems since the channel model adopted does not favor a large difference in the channel gains between users.
Asunto(s)
Noma , Humanos , Algoritmos , Evolución Biológica , Análisis por Conglomerados , RegistrosRESUMEN
The metabolic plasticity of mitochondria ensures cell development, differentiation, and survival. The peptidase OMA1 regulates mitochondrial morphology via OPA1 and stress signaling via DELE1 and orchestrates tumorigenesis and cell survival in a cell- and tissue-specific manner. Here, we use unbiased systems-based approaches to show that OMA1-dependent cell survival depends on metabolic cues. A metabolism-focused CRISPR screen combined with an integrated analysis of human gene expression data found that OMA1 protects against DNA damage. Nucleotide deficiencies induced by chemotherapeutic agents promote p53-dependent apoptosis of cells lacking OMA1. The protective effect of OMA1 does not depend on OMA1 activation or OMA1-mediated OPA1 and DELE1 processing. OMA1-deficient cells show reduced glycolysis and accumulate oxidative phosphorylation (OXPHOS) proteins upon DNA damage. OXPHOS inhibition restores glycolysis and confers resistance against DNA damage. Thus, OMA1 dictates the balance between cell death and survival through the control of glucose metabolism, shedding light on its role in cancerogenesis.
Asunto(s)
Metaloendopeptidasas , Péptido Hidrolasas , Humanos , ADN/metabolismo , GTP Fosfohidrolasas/metabolismo , Metaloendopeptidasas/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Fosforilación Oxidativa , Péptido Hidrolasas/metabolismoRESUMEN
Os hemangiomas são tumores benignos não invasivos e nem metastáticos, embora alguns autores acreditem que a transformação maligna possa ocorrer em alguns casos multicêntricos e nos tumores induzidos pela luz do sol. O objetivo do trabalho foi relatar um caso de hemangioma cutâneo com presença de calcinose circunscrita, em uma cadela da raça rottweiler, de um ano de idade, atendida no Hospital Veterinário da Faculdade de Veterinária, Moçambique. O tratamento foi cirúrgico, sendo o hemograma e bioquímica sanguínea, exames complementares não conclusivos para um diagnósticodefi nitivo, que foi obtido pela histopatologia.
Hemangioma is a benign tumor or metastatic non-invasive tumor, although some authors believe that malignant transformation may occur in some cases and in multicentric tumors induced by the sun light. This study aims to report a case of cutaneous hemangioma with the presence of circumscribed calcinosis in a rottweiler bitch, one year old, attended at the Veterinary Hospital, Veterinary College, Mozambique. The treatment was surgical and the hemogram and blood biochemistry were inconclusive for a defi nitive diagnosis, obtained only by histopathology.
Asunto(s)
Animales , Perros , Perros , Hemangioma/veterinaria , Calcinosis , Neoplasias/veterinariaRESUMEN
Os hemangiomas são tumores benignos não invasivos e nem metastáticos, embora alguns autores acreditem que a transformação maligna possa ocorrer em alguns casos multicêntricos e nos tumores induzidos pela luz do sol. O objetivo do trabalho foi relatar um caso de hemangioma cutâneo com presença de calcinose circunscrita, em uma cadela da raça rottweiler, de um ano de idade, atendida no Hospital Veterinário da Faculdade de Veterinária, Moçambique. O tratamento foi cirúrgico, sendo o hemograma e bioquímica sanguínea, exames complementares não conclusivos para um diagnósticodefi nitivo, que foi obtido pela histopatologia. (AU)
Hemangioma is a benign tumor or metastatic non-invasive tumor, although some authors believe that malignant transformation may occur in some cases and in multicentric tumors induced by the sun light. This study aims to report a case of cutaneous hemangioma with the presence of circumscribed calcinosis in a rottweiler bitch, one year old, attended at the Veterinary Hospital, Veterinary College, Mozambique. The treatment was surgical and the hemogram and blood biochemistry were inconclusive for a defi nitive diagnosis, obtained only by histopathology. (AU)