Gaining assurance in a voter-verifiable voting system

The literature on e-voting systems has many examples of discussion of the correctness of the computer and communication algorithms of such systems, as well as discussions of their vulnerabilities. However, a gap in the literature concerns the practical need (before adoption of a specific e-voting system) for a complete case demonstrating that the system as a whole has sufficiently high probability of exhibiting the desired properties when in use in an actual election. This paper discusses the problem of producing such a case, with reference to a specific system: a version of the Prêt à Voter scheme for voter-verifiable e-voting. We show a possible organisation of a case in terms of four main requirements – accuracy, privacy, termination and ‘trustedness’– and show some of the detailed organisation that such a case should have, the diverse kinds of evidence that needs to be gathered and some of the interesting difficulties that arise

Kinks, rings, and rackets in filamentous structures

Carbon nanotubes and biological filaments each spontaneously assemble into kinked helices, rings, and "tennis racket" shapes due to competition between elastic and interfacial effects. We show that the slender geometry is a more important determinant of the morphology than any molecular details. Our mesoscopic continuum theory is capable of quantifying observations of these structures, and is suggestive of their occurrence in other filamentous assemblies as well.Comment: This paper was originally published in PNAS 100: 12141-12146 (2003). The present version has corrected Eq. 3, A1, and A2, and some minor typo

Structure and composition of the benthic macroinvertebrate community on wetland and irrigated rice cultivation.

Wetlands are environmentally and economically important ecosystems. The irrigated rice crops are considered artificial wetlands, because they offer food and refuge to different aquatic communities. The benthic macroinvertebrates are used to study environmental quality. The knowledge from the organisms which inhabit the natural and artificial wetlands can help to verify less harmful management practices in the agroecosystems. AIM: The aim of this research was to analyze and compare the benthic macroinvertebrate community from a wetland and an experimental kind of rice cultivation. METHODS: It was used dip nets 1 mm mesh every 15 days, with six repetitions in each place, from January to March 2010. After washing and screening them in the laboratory, the organisms were identified using stereoscope microscope and identification keys, and classified according to their functional trophic group. RESULTS: The whole organisms collected were 33,293 specimens. It was found 34 taxa, being 26 founded in the rice crops and 31 on the wetland. The natural wetland shows greater abundance, being responsible for 90.47% from the total abundance in this study. In the rice crop the abundance and the richness increased in the course of collection. However, it did not reach the values founded in the wetlands during the cultivation period. The most found groups in the two environmental were Belostomatidae and Planorbidae, while Hyalellidae and Elmidae were found only in the wetland, being a stress indicator in the wetland. CONCLUSIONS: The community structure including abundance, richness and composition was statistical different between wetlands and rice cultivation

Residual effect of Fipronil used in rice farming on non-target organisms.

This study evaluated changes in the composition of the benthic community of non-target organisms in rice crop fields due to residual effect one year after planting seeds treated with different Fipronil doses. Macroinvertebrates were collected during crop irrigation months (February, March and April/2012), with the aid of 1 mm hand net placed close to the ground of each plot, for 20 minutes, collected macroinvertebrates were classified according to its dietary habits function. Orizophagus oryzae larvae, the target organisms, were not found in groups treated with different Fipronil doses; they were only observed in the control treatment. Chironominae (Chironomidae: Diptera) larvae had their population reduced in comparison to the control treatment. However, the herein used insecticide doses did not show significant changes in the benthic macroinvertebrate community one year after their application

Evaluación preliminar de la regeneración natural de Pinus elliottii Engelm, en Gualeguaychú, provincia de Entre Ríos

p.219-227Es ampliamente conocida la importancia de la especie Pinus elliottii como componente de forestaciones comerciales en Argentina. Existen varios antecedentes que evidencian la capacidad de regeneración natural de la misma, en diversas áreas del país. Se analizaron diferentes situaciones, observadas en una forestación de aproximadamente 3000 ha, ubicadas en cercanías de la localidad de Gualeguaychú (Entre Ríos), la cual presentaba una variada gama de edades. Se observó regeneración natural con diverso grado de desarrollo y uniformidad, bajo dosel y sin cobertura arbórea. El trabajo incluye un estudio sobre la dinámica de la regeneración bajo dosel en brinzales, y una caracterización estructural de rodales restablecidos, en condiciones de ser aprovechados comercialmente. Al estado de brinzal se registraron densidades del orden de 46 a 86 pl-m2, con diámetros a la altura del cuello entre 1,5 y 16,5 mm, y alturas entre 15 y 125 cm. Rodales restablecidos de 15 años de edad presentaron 1867 pl-ha, con un diámetro promedio (DPR) de 20,47 cm. altura del árbol tipo de 15,20 m. Siendo el volumen total c-c- de 551 m3-h

Minimising medicine use in organic dairy herds through animal health and welfare planning

Livestock is important in many organic farming systems, and it is an explicit goal to ensure high levels of animal health and welfare (AHW) through good management. This will lead to reduced medicine use and better quality of animal products. In two EU network projects NAHWOA & SAFO it was concluded that this is not guaranteed merely by following organic standards. Both networks recommended implementation of individual animal health plans to stimulate organic farmers to improve AHW. These plans should include a systematic evaluation of AHW and be implemented through dialogue with each farmer in order to identify goals and plan improvements. 15 research institutions in 8 European countries are involved in the proposed project with the main objective to minimise medicine use in organic dairy herds through active and well planned AHW promotion and disease prevention. The project consists of 5 work packages, 4 of which comprise research activities building on current research projects, new applications across borders, exchange of knowledge, results and conclusions between participating countries, and adopting them to widely different contexts. International and national workshops facilitate this exchange. Focus areas are animal health planning, AHW assessment using animal based parameters and development of advisory systems and farmer groups. Epidemiological analyses of the effect on AHW from reduced medicine use and herd improvements are planned in all participating countries

Aspectos ambientais do cultivo de arroz orgânico, biodinâmico e convencional.

Este trabalho tem o objetivo de comparar aspectos ambientais dos diferentes sistemas manejo de arroz irrigado orgânico, biodinâmico e convencional.SIAPEX