A Survey on Long-Range Wide-Area Network Technology Optimizations

Long-Range Wide-Area Network (LoRaWAN) enables flexible long-range service communications with low power consumption which is suitable for many IoT applications. The densification of LoRaWAN, which is needed to meet a wide range of IoT networking requirements, poses further challenges. For instance, the deployment of gateways and IoT devices are widely deployed in urban areas, which leads to interference caused by concurrent transmissions on the same channel. In this context, it is crucial to understand aspects such as the coexistence of IoT devices and applications, resource allocation, Media Access Control (MAC) layer, network planning, and mobility support, that directly affect LoRaWAN’s performance.We present a systematic review of state-of-the-art works for LoRaWAN optimization solutions for IoT networking operations. We focus on five aspects that directly affect the performance of LoRaWAN. These specific aspects are directly associated with the challenges of densification of LoRaWAN. Based on the literature analysis, we present a taxonomy covering five aspects related to LoRaWAN optimizations for efficient IoT networks. Finally, we identify key research challenges and open issues in LoRaWAN optimizations for IoT networking operations that must be further studied in the future

Analysis of evolution of Parecis Basin through potential methods.

A intracrat?nica Bacia dos Parecis est? localizada na regi?o centro-oeste do Brasil, no setor sudoeste do Cr?ton Amaz?nico, recobrindo partes das prov?ncias Suns?s, Rond?nia-Juruena e Tapaj?s-Parima (Santos 2002). Ap?s os trabalhos de Teixeira (1993) e Siqueira (1989), embasados em dados geof?sicos e geol?gicos, a bacia foi dividida, de oeste para leste, em tr?s dom?nios tectono-sedimentares: o extremo oeste, uma depress?o tect?nica ( Fossa Tect?nica de Rond?nia); a por??o central, um baixo gravim?trico e o extremo leste, uma bacia interior denominada por Schobbenhaus (1984) de Bacia do Alto Xing?. Durante o Ordoviciano at? o Eo-Permiano, a regi?o Amaz?nica foi afetada por um evento extensional, quando foram depositados os sedimentos ordovicianos da Forma??o Cacoal, representando o registro do est?gio rifte da Bacia dos Parecis. Do Devoniano ao Eo-Permiano as forma??es Furnas, Ponta Grossa, Pimenta Bueno e Fazenda da Casa Branca foram depositadas durante o est?gio sag da bacia. Durante o Mesoz?ico (Tri?ssico ao Cret?ceo) uma sucess?o de rochas vulc?nicas e sedimentares representa outro evento extensional . Este evento est? representado na Bacia dos Parecis pelos arenitos e?licos da Forma??o Rio ?vila e os derrames bas?lticos das forma??es Anar? e Tapirapu?. O Grupo Parecis, composto de conglomerados e arenitos, representa o est?gio deposicional relacionado ao Cret?ceo. Os dados gravim?tricos e magn?ticos da Bacia dos Parecis foram adquiridos pelo IBGE, PETROBRAS e CPRM. O mapa gravim?trico da Bacia dos Parecis obtido atrav?s do software O?sis/Geosoft mostra uma extensa anomalia Bouguer negativa que se destaca no interior do Cr?ton Amaz?nico, com desvio do campo regional da ordem de ?40 mgl. O trend estrutural regional de dire??o leste-oeste, com desvio do campo regional da ordem de 80 mgal, evidencia o prosseguimento dos grabens de Pimenta Bueno e Colorado, os quais comp?em a Fossa Tect?nica de Rond?nia, por baixo da seq??ncia mesoz?ica. A exist?ncia dessa estrutura ? sustentada pelo mapa da Deconvolu??o de Euler, obtido atrav?s de um processo de invers?o, a qual segue uma estimativa da profundidade da anomalia relacionada ao embasamento cristalino.The Parecis basin is located in central-western Brazil, on the southwestern part of the Amazon Craton, partially covering the Suns?s, Rond?nia-Juruena and Tapaj?s-Parima provinces (Santos 2002). Based on Teixeira (1993) and Siqueira (1989), the Parecis basin was divided, from west to east, into three tectono-sedimentary domains: the Rond?nia tectonic, the central compartment ( negative gravimetric anomaly) and a interior sag (Alto Xingu basin). During the Ordovician to Early Permian, the eastern Amazon region was affected by an extensional event and the Cacoal formation was deposited (rift stage of the Parecis basin). From Devonian to Early Permian, Furnas, Ponta Grossa, Pimenta Bueno and Fazenda da Casa Branca formations were deposited during the sag stage of the basin. Mesozoic (Late Triassic to Cretaceous) volcanic and sedimentary successions record another extensional event in the Amazon region. This event is represented in the Parecis basin by the eolian sandstones of the Rio ?vila Formation and the basalts of the Anar? and Tapirapu? formations. The Cretaceous depositional stage is represented by the Parecis Group. Gravity and magnetic data of the Parecis basin have been acquired by IBGE, PETROBRAS and CPRM. Gravimetry and magnetometry maps obtained through the use of the Oasis/Geosoft software show an extensive negative anomaly in the interior of the Amazon Craton, with an average deviation from regional field of -40 mgal. The east-west regional structural trend with a deviation from regional field of -80 mgal evidences the eastward continuity of Pimenta Bueno and Colorado grabens underneath the Mesozoic succession (Rond?nia tectonic low). The existence of this structure is supported by the Euler Deconvolution map, obtained through an inversion procedure that allowed an estimation of the anomaly (basement) depth

Abstracts

Tradução, para a língua inglesa, dos resumos dos artigos publicados nesta edição

Oxidative modification of proteins: from damage to catalysis, signaling, and beyond

Significance: The systematic investigation of oxidative modification of proteins by reactive oxygen species started in 1980. Later, it was shown that reactive nitrogen species could also modify proteins. Some protein oxidative modifications promote loss of protein function, cleavage or aggregation, and some result in proteo-toxicity and cellular homeostasis disruption. Recent Advances: Previously, protein oxidation was associated exclusively to damage. However, not all oxidative modifications are necessarily associated with damage, as with Met and Cys protein residue oxidation. In these cases, redox state changes can alter protein structure, catalytic function, and signaling processes in response to metabolic and/or environmental alterations. This review aims to integrate the present knowledge on redox modifications of proteins with their fate and role in redox signaling and human pathological conditions. Critical Issues: It is hypothesized that protein oxidation participates in the development and progression of many pathological conditions. However, no quantitative data have been correlated with specific oxidized proteins or the progression or severity of pathological conditions. Hence, the comprehension of the mechanisms underlying these modifications, their importance in human pathologies, and the fate of the modified proteins is of clinical relevance. Future Directions: We discuss new tools to cope with protein oxidation and suggest new approaches for integrating knowledge about protein oxidation and redox processes with human pathophysiological conditions

Approaches in biotechnological applications of natural polymers

Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)