Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

Criptococose Cutânea Primária em Paciente Imunocompetente: Um Relato de Caso

Cryptococcosis is a systemic infection caused by Cryptococcus neoformans, an encapsulated opportunistic yeast. It primarily causes significant infections in immunocompromised individuals and the symptoms vary according to the integrity of the immune system. Cutaneous cryptococcosis affects about 20% of patients with disseminated cryptococcosis, but primary cutaneous cryptococcosis (PCC) without systemic infection is rare. A 76-year-old male patient with chronic obstructive pulmonary disease, hypertension and dyslipidemia, presented with a violaceus inflammatory skin plaque with blisters that progressed despite intravenous ceftriaxone for 7 days. Histopathology of an incisional biopsy was compatible with the diagnosis of cutaneous cryptococcosis. There was a complete response to fluconazole 300 mg/day for 3 months. No systemic disease was detected and there was no evidence of immunosuppression. The importance of including cutaneous cryptococcosis in the differential diagnosis of skin lesions in patients without immunosuppression or the use of immunosuppressive therapy is emphasized. The cutaneous manifestations of the infection can be the first indication for a disseminated disease, therefore, its early recognition is essential to obtain a good prognosis.A criptococose é uma infecção sistémica causada por Cryptococcus neoformans, levedura oportunista encapsulada. Esta infeção ocorre principalmente em indivíduos imunocomprometidos e os sintomas variam de acordo com a integridade do sistema imunológico. A criptococose cutânea afeta aproximadamente 20% dos pacientes com criptococose disseminada, mas a criptococose cutânea primária (PCC) sem infecção sistémica é rara. Um paciente do sexo masculino de 76 anos, com doença pulmonar obstrutiva crónica, hipertensão arterial e dislipidemia, apresentou-se com placa cutânea inflamatória violácea com bolhas que progrediu apesar de ceftriaxone endovenoso por 7 dias, sem sucesso. A biópsia incisional revelou o diagnóstico histopatológico de criptococose cutânea. As lesões resolveram após tratamento com fluconazol 300 mg/dia durante 3 meses. Não se detectou doença sistémica e não havia qualquer evidência de imunossupressão. Enfatiza-se a importância da inclusão da criptococose cutânea no diagnóstico diferencial das lesões cutâneas, mesmo em pacientes sem terapia imunossupressora. As manifestações cutâneas da infecção podem ser o primeiro indício para uma doença disseminada, pelo que o seu reconhecimento precoce é fundamental para um bom prognóstico

The effect of data analysis strategies in density estimation of mountain ungulates using distance sampling

Distance sampling is being extensively used to estimate the abundance of animal populations. Nevertheless, the great variety of ways in which data can be analyzed may limit comparisons due to the lack of standardization of such protocols. In this study, the influence of analytical procedures for distance sampling data on density estimates and their precision was assessed. We have used data from 21 surveys of mountain ungulates in the Iberian Peninsula, France and the Italian Alps. Data from such surveys were analyzed with the program Distance 6.0. Our analyses show that estimated density can be higher for higher levels of data truncation. We also confirm that the estimates tend to be more precise when data are analyzed without binning and without truncating. We found no evidence of size biased sampling as group size and distances were uncorrelated in most of our surveys. Despite distance sampling being a fairly robust methodology, it can be sensitive to some data analysis strategies

Tectonostratigraphy of Middle and Upper Palaeozoic black shales from the Porto-Tomar-Ferreira do Alentejo shear zone (W Portugal): new perspectives on the Iberian Massif

Middle/late Devonian and early Carboniferous metasedimentary sequences in the northernmost region (Porto-Espinho-Tomar) of the Ossa-Morena Zone (Portuguese Iberian Variscan Massif) contain black shales of very low to low-grade metamorphism. These metasedimentary rocks form a discrete NNW-SSE structure within a major shear zone (Porto-Tomar-Ferreira do Alentejo) and remain subparallel to the observed regional major structures (folding, thrusts or overthrusts). These black shales are overhanged and then imbricated in an upper Proterozoic metamorphic substratum. A multi-disciplinary study of these metasedimentary rocks from the Espinho-Tomar region has tectonostratigraphy, palynology, organic petrology and clay mineralogy combined methods. This approach provides new insights into the tectonic evolution and geological framework of Palaeozoic basement of the Iberian Variscides. Palaeoenvironmental and tectonostratigraphic implications on the Iberian geodynamic framework are discussed.http://www.sciencedirect.com/science/article/B6X0V-4B1S5T3-3/1/df2a39b964c83f2e1e28dfb7cc85309

Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

An iterative pilot-data-aided estimator for SFBC relay-assisted OFDM-based systems

In this article, we propose and assess an iterative pilot-data-aided channel estimation scheme for space frequency block coding relay-assisted OFDM-based systems. The relay node (RN) employs the equalise-and-forward protocol, and both the base station (BS) and the RN are equipped with antenna arrays, whereas the user terminal (UT) is a single-antenna device. The channel estimation method uses the information carried by pilots and data to improve the estimate of the equivalent channels for the path BS-RN-UT. The mean minimum square error criterion is used in the design of the estimator for both the pilot-based and data-aided iterations. In different scenarios, with only one data iteration, the results show that the proposed scheme requires only half of the pilot density to achieve the same performance of non-data-aided schemes