Modelaçcão comportamental da camada física NB-IoT - Uplink

Mestrado em Engenharia Eletrónica e TelecomunicaçõesA Internet das Coisas (IoT) consiste numa rede sem fios de sensores/atuadores ligados entre si e que têm a capacidade de recolher dados. Devido ao crescimento rápido do mercado IoT, as redes de longa distância e baixa potência (LPWAN) tornaram-se populares. O NarrowBand-IoT (NB-IoT), desenvolvido pela 3rd Generation Partnership Project (3GPP), é um desses protocolos. O principal objectivo desta dissertação é a implementação de uma simulação comportamental em MATLAB do NB-IoT no uplink, que será disponibilizada abertamente. Esta será focada, primariamente, na camada física e nas suas respetivas funcionalidades, nomeadamente turbo coding, modulação SC-FDMA, modelos de simulação de canal, desmodulação SC-FDMA, estimação de canal, equalizador e turbo decoding. A estimação de canal é feita usando símbolos piloto previamente conhecidos. Os modelos de canal utilizados são baseados nas especificações oficiais da 3GPP. A taxa de bits errados (BER) é calculada e usada de forma a avaliar a performance do turbo encoder e do equalizador zero forcing (ZF). Serve também como comparação quando a implementação usa esquemas de modulação diferentes (Binary Phase-Shift Keying (BPSK) e Quadrature Phase-Shift Keying (QPSK)). Além disso, os sinais gerados em MATLAB são transmitidos usando como front-end de radio-frequência (RF) uma Universal Software Radio Peripheral (USRP). Posteriormente, são recebidos, desmodulados e descodificados. Finalmente, é obtida a constelação do sinal, a BER é calculada e os resultados são analisados.The Internet of Things (IoT) refers to a wireless network of interconnected sensors/actuators with data-collecting technologies. Low Power Wide Area Networks (LPWAN) have become popular due to the rapid growth of the IoT market. Narrowband-IoT (NB-IoT), developed by 3rd Generation Partnership Project (3GPP), is one of these protocols. The main objective of this thesis is the implementation of an open-source uplink behavioral simulator based on MATLAB. Its focus is primarily on Layer 1 (physical layer) relevant functionalities, namely turbo coding, Single-Carrier Frequency-Division Multiple Access (SC-FDMA) modulation, channel modeling, SC-FDMA demodulation, channel estimation, equalization and turbo decoding. Channel estimation is performed using known pilot symbols. The used channel models are based on the 3GPP o cial release specs. The Bit Error Rate (BER) is calculated in order to evaluate the turbo encoder and the Zero Forcing (ZF) equalizer performance, and to compare Binary Phase-Shift Keying (BPSK) and Quadrature Phase-Shift Keying (QPSK) implementations. Furthermore, the MATLAB generated signal is transmitted using a radio-frequency (RF) front-end consisting of an Universal Software Radio Peripheral (USRP). Afterwards, the signal is received, demodulated and decoded. A constellation is obtained, the BER is calculated and the results are analyzed

Prevention of hypertension in patients with pre-hypertension: protocol for the PREVER-prevention trial

<p>Abstract</p> <p>Background</p> <p>Blood pressure (BP) within pre-hypertensive levels confers higher cardiovascular risk and is an intermediate stage for full hypertension, which develops in an annual rate of 7 out of 100 individuals with 40 to 50 years of age. Non-drug interventions to prevent hypertension have had low effectiveness. In individuals with previous cardiovascular disease or diabetes, the use of BP-lowering agents reduces the incidence of major cardiovascular events. In the absence of higher baseline risk, the use of BP agents reduces the incidence of hypertension. The PREVER-prevention trial aims to investigate the efficacy, safety and feasibility of a population-based intervention to prevent the incidence of hypertension and the development of target-organ damage.</p> <p>Methods</p> <p>This is a randomized, double-blind, placebo-controlled clinical trial, with participants aged 30 to 70 years, with pre-hypertension. The trial arms will be chlorthalidone 12.5 mg plus amiloride 2.5 mg or identical placebo. The primary outcomes will be the incidence of hypertension, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new sub-clinical atherosclerosis, and sudden death. The study will last 18 months. The sample size was calculated on the basis of an incidence of hypertension of 14% in the control group, a size effect of 40%, power of 85% and P alpha of 5%, resulting in 625 participants per group. The project was approved by the Ethics committee of each participating institution.</p> <p>Discussion</p> <p>The early use of blood pressure-lowering drugs, particularly diuretics, which act on the main mechanism of blood pressure rising with age, may prevent cardiovascular events and the incidence of hypertension in individuals with hypertension. If this intervention shows to be effective and safe in a population-based perspective, it could be the basis for an innovative public health program to prevent hypertension in Brazil.</p> <p>Trial Registration</p> <p>Clinical Trials <a href="http://www.clinicaltrials.gov/ct2/show/NCT00970931">NCT00970931</a>.</p

TPE magazine international

BACKGROUND: Cardiovascular disease is the leading cause of death in Brazil, and hypertension is its major risk factor. The benefit of its drug treatment to prevent major cardiovascular events was consistently demonstrated. Angiotensin-receptor blockers (ARB) have been the preferential drugs in the management of hypertension worldwide, despite the absence of any consistent evidence of advantage over older agents, and the concern that they may be associated with lower renal protection and risk for cancer. Diuretics are as efficacious as other agents, are well tolerated, have longer duration of action and low cost, but have been scarcely compared with ARBs. A study comparing diuretic and ARB is therefore warranted. METHODS/DESIGN: This is a randomized, double-blind, clinical trial, comparing the association of chlorthalidone and amiloride with losartan as first drug option in patients aged 30 to 70 years, with stage I hypertension. The primary outcomes will be variation of blood pressure by time, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new subclinical atherosclerosis and sudden death. The study will last 18 months. The sample size will be of 1200 participants for group in order to confer enough power to test for all primary outcomes. The project was approved by the Ethics committee of each participating institution. DISCUSSION: The putative pleiotropic effects of ARB agents, particularly renal protection, have been disputed, and they have been scarcely compared with diuretics in large clinical trials, despite that they have been at least as efficacious as newer agents in managing hypertension. Even if the null hypothesis is not rejected, the information will be useful for health care policy to treat hypertension in Brazil. CLINICAL TRIALS REGISTRATION NUMBER: ClinicalTrials.gov: NCT0097116

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved

Núcleos de Ensino da Unesp: artigos 2008

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data