2,274 research outputs found
Anthropology And The Process Of The Construction Of Homosexual Citizenship In Brazil
In order to contribute to the more general reflection on the links between science and politics, I discuss in this article how, in practice, social anthropologists build their knowledge. Moving continually through the fluid boundaries between LGBT activism and academic reflection, Brazilian social anthropologists became important actors in the process of promoting “homosexual citizenship” in Brazil. I focus in more detail on two different historical contexts: the late 1970s and mid-1980s, when the homosexual movement began to be organized in Brazil; and the first decade of the 2000s, when I began to developed my own research. © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.20164
Biosensors for Biomolecular Computing: a Review and Future Perspectives
Biomolecular computing is the field of engineering where computation, storage, communication, and coding are obtained by exploiting interactions between biomolecules, especially DNA, RNA, and enzymes. They are a promising solution in a long-term vision, bringing huge parallelism and negligible power consumption. Despite significant efforts in taking advantage of the massive computational power of biomolecules, many issues are still open along the way for considering biomolecular circuits as an alternative or a complement to competing with complementary metal–oxide–semiconductor (CMOS) architectures. According to the Von Neumann architecture, computing systems are composed of a central processing unit, a storage unit, and input and output (I/O). I/O operations are crucial to drive and read the computing core and to interface it to other devices. In emerging technologies, the complexity overhead and the bottleneck of I/O systems are usually limiting factors. While computing units and memories based on biomolecular systems have been successfully presented in literature, the published I/O operations are still based on laboratory equipment without a real development of integrated I/O. Biosensors are suitable devices for transducing biomolecular interactions by converting them into electrical signals. In this work, we explore the latest advancements in biomolecular computing, as well as in biosensors, with focus on technology suitable to provide the required and still missing I/O devices. Therefore, our goal is to picture out the present and future perspectives about DNA, RNA, and enzymatic-based computing according to the progression in its I/O technologies, and to understand how the field of biosensors contributes to the research beyond CMOS
Sodium lactate solutions characterization using Electrochemical Impedance Spectroscopy
Lactate is an important metabolite in human body and, among possible medical applications, it can be used to monitor physical activity. Actually, its concentration represents a clear indication whether optimal training intensity is kept or if muscles are under anaerobic conditions. Routine procedures to measure lactate concentration during physical activity are represented by invasive measurements, which require blood sampling from the patient or the athlete. So, a great advantage would be derived by the possibility to monitor this analyte using non-invasive techniques. Considering the possibility to measure lactate in human sweat during sport activities, this paper presents the characterization of saline aqueous solutions containing sodium lactate by means of Electrochemical Impedance Spectroscopy (EIS). Measurements were performed using a two-electrode electrochemical cell and acquired spectra were analyzed also by means of equivalent electrical circuit (EEC) modeling. Results show an effect due to lactate concentration on solution impedance in the high-frequency region of spectrum, where a change in solution resistance is measured. At the same time, no changes in the measured capacitance were found. Future work will study the electrochemical behavior of lactate solutions also at higher frequencies to further investigate the possible use of EIS for lactate levels monitoring during sport activities
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Declining Burden of Plasmodium vivax in a Population in Northwestern Thailand from 1995 to 2016 before Comprehensive Primaquine Prescription for Radical Cure.
All Plasmodium cases have declined over the last decade in northwestern Thailand along the Myanmar border. During this time, Plasmodium vivax has replaced Plasmodium falciparum as the dominant species. The decline in P. falciparum has been shadowed by a coincidental but delayed decline in P. vivax cases. This may be due to early detection and artemisinin-based therapy, species-specific diagnostics, and bed net usage all of which reduce malaria transmission but not P. vivax relapse. In the absence of widespread primaquine use for radical cure against P. vivax hypnozoites, the decline in P. vivax may be explained by decreased hypnozoite activation of P. vivax relapses triggered by P. falciparum. The observed trends in this region suggest a beneficial effect of decreased P. falciparum transmission on P. vivax incidence, but elimination of P. vivax in a timely manner likely requires radical cure
An Integrated Platform for Differential Electrochemical and ISFET Sensing
A fully-integrated differential biosensing platform on CMOS is presented for miniaturized enzyme-based electrochemical sensing. It enables sensor background current elimination and consists of a differential sensor array and a differential readout IC (DiRIC). The sensor array includes a four-electrode sensor for amperometric electrochemical sensing, as well as a differential ISFET-based pH sensor to calibrate the biosensors. The ISFET is biased in weak inversion and co-designed with DiRIC to enable pH measurements from 1 to 14 with resolution of 0.1 pH. DiRIC enables differential current measurement in the range of ¿¿100 ¿¿A with more than 120dB dynamic range
Spatially variable rate herbicide application on durum wheat in Sicily
Using the conventional farming system, durum wheat requires high rates of herbicide spraying.
Herbicide residues can cause pollution of soil and ground water and, therefore, of the entire environment.
In order to minimise the environmental impact of herbicides, a home made system for spatially variable rate crop input application was designed, developed and set up by the Department of Engineering and Technologies in Agriculture and Forestry (I.T.A.F.). This system consists of a DGPS, a portable computer, a specifically developed software and a device for applying rates proportionally related to the machine forward speed (DPA).
Tests of spatially variable rate herbicide application were carried out in inland Sicily, on a field of 8.4 ha (where a three-year crop rotation, broad bean/vetch - durum wheat - durum wheat, was practised), using a sprayer modified for applying variable rates and equipped with the above mentioned system.
The results are promising. The spatially variable rate herbicide application allowed an almost even grain yield over the entire field and a saving of 29% of herbicides with respect to the amounts normally used with the conventional farming system
All-in-Fiber Electrochemical Sensing
Electrochemical sensors have found a wide range of applications in analytical chemistry thanks to the advent of high-throughput printing technologies. However, these techniques are usually limited to two-dimensional (2D) geometry with relatively large minimal feature sizes. Here, we report on the scalable fabrication of monolithically integrated electrochemical devices with novel and customizable fiber-based architectures. The multimaterial thermal drawing technique is employed to co-process polymer composites and metallic glass into uniform electroactive and pseudoreference electrodes embedded in an insulating polymer cladding fiber. To demonstrate the versatility of the process, we tailor the fiber microstructure to two configurations: a small-footprint fiber tip sensor and a high-surface-area capillary cell. We demonstrate the performance of our devices using cyclic voltammetry and chronoamperometry for the direct detection and quantification of paracetamol, a common anesthetic drug. Finally, we showcase a fully portable pipet-based analyzer using low-power electronics and an "electrochemical pipet tip" for direct sampling and analysis of microliter-range volumes. Our approach paves the way toward novel materials and architectures for efficient electrochemical sensing to be deployed in existing and novel personal care and surgical configurations
Gradings of non-graded Hamiltonian Lie algebras
A thin Lie algebra is a Lie algebra graded over the positive integers
satisfying a certain narrowness condition. We describe several cyclic grading
of the modular Hamiltonian Lie algebras H(2\colon\n;\omega_2) (of dimension
one less than a power of ) from which we construct infinite-dimensional thin
Lie algebras. In the process we provide an explicit identification of
H(2\colon\n;\omega_2) with a Block algebra. We also compute its second
cohomology group and its derivation algebra (in arbitrary prime
characteristic).Comment: 36 pages, to be published in J. Austral. Math. Soc. Ser.
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