Efficient and Modular Consensus-Free Reconfiguration for Fault-Tolerant Storage

Quorum systems are useful tools for implementing consistent and available storage in the presence of failures. These systems usually comprise of a static set of servers that provide a fault-tolerant read/write register accessed by a set of clients. We consider a dynamic variant of these systems and propose FreeStore, a set of fault-tolerant protocols that emulates a register in dynamic asynchronous systems in which processes are able to join/leave the set of servers during the execution. These protocols use a new abstraction called view generators, that captures the agreement requirements of reconfiguration and can be implemented in different system models with different properties. Particularly interesting, we present a reconfiguration protocol that is modular, efficient, consensus-free and loosely coupled with read/write protocols. An analysis and an experimental evaluation show that the proposed protocols improve the overall system performance when compared with previous solutions

Sharing Memory between Byzantine Processes using Policy-enforced Tuple Spaces

Abstract—Despite the large amount of Byzantine fault-tolerant algorithms for message-passing systems designed through the years, only recent algorithms for the coordination of processes subject to Byzantine failures using shared memory have appeared. This paper presents a new computing model in which shared memory objects are protected by fine-grained access policies, and a new shared memory object, the Policy-Enforced Augmented Tuple Space (PEATS). We show the benefits of this model by providing simple and efficient consensus algorithms. These algorithms are much simpler and require less shared memory operations, using also less memory bits than previous algorithms based on access control lists (ACLs) and sticky bits. We also prove that PEATS objects are universal, i.e., that they can be used to implement any other shared memory object, and present lock-free and wait-free universal constructions. Index Terms—Byzantine fault-tolerance, shared memory algorithms, tuple spaces, consensus, universal constructions. Ç

Skull Development, Ossification Pattern, and Adult Shape in the Emerging Lizard Model Organism Pogona vitticeps: A Comparative Analysis With Other Squamates

The rise of the Evo-Devo field and the development of multidisciplinary research tools at various levels of biological organization have led to a growing interest in researching for new non-model organisms. Squamates (lizards and snakes) are particularly important for understanding fundamental questions about the evolution of vertebrates because of their high diversity and evolutionary innovations and adaptations that portrait a striking body plan change that reached its extreme in snakes. Yet, little is known about the intricate connection between phenotype and genotype in squamates, partly due to limited developmental knowledge and incomplete characterization of embryonic development. Surprisingly, squamate models have received limited attention in comparative developmental studies, and only a few species examined so far can be considered as representative and appropriate model organism for mechanistic Evo-Devo studies. Fortunately, the agamid lizard Pogona vitticeps (central bearded dragon) is one of the most popular, domesticated reptile species with both a well-established history in captivity and key advantages for research, thus forming an ideal laboratory model system and justifying his recent use in reptile biology research. We first report here the complete post-oviposition embryonic development for P. vitticeps based on standardized staging systems and external morphological characters previously defined for squamates. Whereas the overall morphological development follows the general trends observed in other squamates, our comparisons indicate major differences in the developmental sequence of several tissues, including early craniofacial characters. Detailed analysis of both embryonic skull development and adult skull shape, using a comparative approach integrating CT-scans and gene expression studies in P. vitticeps as well as comparative embryology and 3D geometric morphometrics in a large dataset of lizards and snakes, highlights the extreme adult skull shape of P. vitticeps and further indicates that heterochrony has played a key role in the early development and ossification of squamate skull bones. Such detailed studies of embryonic character development, craniofacial patterning, and bone formation are essential for the establishment of well-selected squamate species as Evo-Devo model organisms. We expect that P. vitticeps will continue to emerge as a new attractive model organism for understanding developmental and molecular processes underlying tissue formation, morphology, and evolution.Peer reviewe

A EXPERIÊNCIA DO PROJETO INTEGRADOR l NO CURSO DE PROEJA EM ELETROMECÂNICA DO IF-SC CAMPUS CHAPECÓ

Este trabalho apresenta a experiência vivenciada por meio da unidade curricular Projeto Integrador I, oferecida aos educandos do curso Técnico de Nível Médio em Eletromecânica na Modalidade de Educação de Jovens e Adultos. Trata-se de uma síntese dos avanços, difi culdades e desafi os de um trabalho ainda em construção por professores e toda a equipe de servidores do Campus Chapecó.O estudo usa como referência registros de distintas atividades realizadas coletivamente neste curso por educadores e educandos a partir do primeiro semestre de 2009. A principal conclusão do trabalho é que os Projetos Integradores, se construídos nos moldes apresentados, são uma importante ferramenta para a aprendizagem, a integração curricular e para a difusão de experiências educativas inovadoras e bem sucedidas

Produção de multimídia e acessibilidade em cursos de aprendizagem a distância

Estudantes online que são surdos podem encontrar diferentes barreiras em cursos baseados na Web incluindo falta de imagens relacionadas ao conteúdo em páginas tomadas por texto. As diferentes barreiras podem diminuir a compreensão para pessoas cuja primeira língua seja a linguagem de sinais ao invés da linguagem escrita, um desafio para pesquisadores e professores interessados em desenvolver conteúdo multimídia. A combinação de texto, imagem, áudio e vídeo foi potencializada devido à convergência digital e passa a caracterizar os textos virtuais. O uso de multimídia agora permite diferentes efeitos na elaboração de significados. Nesta perspectiva de mudanças constantes, este artigo busca discutir alguns dos muitos desafios para o oferecimento de Cursos de Graduação em larga escala, apresentando algumas das características dos Cursos de Graduação em Letras-Libras. Também se discute a acessibilidade de conteúdo educacional digital multimídia no contexto de um projeto em andamento na UNICAMP.Online students who are deaf may encounter different barriers on Web based courses including lack of content-related images in pages full of text. The different barriers can slow comprehension for people whose first language may be a sign language instead of a written language, a challenge for researchers and teachers interested in developing multimedia content. The intermix of text, image, audio, and video has been increased due to the digital convergence and characterize the virtual texts. Multimedia usage now brings different effects on meaning making. In this perspective, this paper intends to discuss some of the many challenges in the offer of large scale undergraduate courses presenting some characteristics of a course on the Brazilian Sign Language. The paper discusses educational digital multimedia content accessibility in the context of an ongoing project at UNICAMP

Caracterização e avaliação preliminar da ecotoxicidade de resíduo de indústrias de papelão

Paper and paperboard industry generate solid waste that demands correct treatment or disposal. The objective of this work was to characterize the solid waste of two paperboard industries located in Santa Catarina and to assess its ecotoxicity. The characterization involved the determination of moisture, ashes, and cellulose content. Ecotoxicity tests included avoidance behavior tests with earthworms (Eisenia andrei), reproduction tests with collembolans (Folsomia candida), and a test of germination and growth of roots of lettuce (Lactuca sativa). Results of the ecotoxicity tests were assessed using ANOVA followed by tests of Tukey and Dunnett and Fisher exact test (p<0.05). Wastes 1 and 2 presented moisture of 87.23 and 60.80%, ashes 11.18 and 55.12%, and cellulose 59.34 and 66.78%, respectively. Avoidance and reproduction tests did not indicate ecotoxicity for earthworms and collembolans when compared to the soil from pinus plantation. Concerning lettuce root growth, Waste 1 showed toxicity for the concentrations of 100, 75, and 50% of its elutriate. The results indicated that the wastes have chemical, physical, and ecotoxicological characteristics that may be restrictive for their application on agricultural soils.A indústria de papel e papelão é geradora de resíduos sólidos que demandam correto tratamento e disposição. O trabalho teve por objetivo caracterizar a composição de resíduos de duas empresas de papelão de Santa Catarina e avaliar sua ecotoxicidade. A caracterização foi feita com a determinação da umidade, cinzas e celulose. A ecotoxicidade foi avaliada com ensaios de fuga com minhocas (Eisenia andrei), ensaios de reprodução com colêmbolos (Folsomia candida) e com um teste de germinação e crescimento de raízes de alface (Lactuca sativa). Para as avaliações dos ensaios de toxicidade utilizou-se a ANOVA seguida dos testes de Tukey e/ou Dunnet e o teste exato de Fisher todos à p<0,05. Os Resíduos 1 e 2 apresentaram umidade de 87,23 e 60,80%, cinzas 11,18 e 55,12% e celulose 59,34 e 66,78%, respectivamente. Os ensaios de fuga e de reprodução não indicaram ecotoxicidade dos resíduos estudados para minhocas e colêmbolos quando comparados ao solo de plantio de pinus. Em relação ao crescimento de raízes, o Resíduo 1 apresentou toxicidade para as concentrações de 100, 75 e 50% do seu elutriato. Os resultados indicaram que os resíduos possuem características químicas, físicas e ecotoxicológicas que podem ser restritivas quanto a sua aplicação em solos agrícolas

The ecological origins of snakes as revealed by skull evolution

The ecological origin of snakes remains amongst the most controversial topics in evolution, with three competing hypotheses: fossorial; marine; or terrestrial. Here we use a geometric morphometric approach integrating ecological, phylogenetic, paleontological, and developmental data for building models of skull shape and size evolution and developmental rate changes in squamates. Our large-scale data reveal that whereas the most recent common ancestor of crown snakes had a small skull with a shape undeniably adapted for fossoriality, all snakes plus their sister group derive from a surface-terrestrial form with non-fossorial behavior, thus redirecting the debate toward an underexplored evolutionary scenario. Our comprehensive heterochrony analyses further indicate that snakes later evolved novel craniofacial specializations through global acceleration of skull development. These results highlight the importance of the interplay between natural selection and developmental processes in snake origin and diversification, leading first to invasion of a new habitat and then to subsequent ecological radiations.Peer reviewe

Riktade åtgärder till störst nytta för miljöskyddet inom jordbruket : slutrapport från TEHO Plus-projektet (2011-2014)

TEHO Plus, Maatalouden vesiensuojelun tehostaminen -hanke jatkoi TEHO-hankkeen aloittamaa työtä vuosina 2011–2014. Hankkeen toiminnan painopistealueina ovat olleet maatalouden ympäristöneuvojien koulutuspaketin luonti ja koulutuksen kokeileminen, tilakohtainen neuvonta ja neuvonnasta saatujen kokemusten hyödyntäminen, tietopaketin kokoaminen maatalouden ympäristöasioista, tilatason kokeilutoiminta ja vedenlaadun seurannan kehittäminen. Ympäristötoimia on neuvonnassa suositeltu kohdennettavaksi paikkatietoaineistoja ja ravinnetaseita hyödyntäen. Hanke toteutettiin Varsinais-Suomen ELY-keskuksen, MTK-Satakunnan ja MTK-Varsinais-Suomen yhteistyönä. Hanketta rahoittivat maa- ja metsätalousministeriö sekä ympäristöministeriö. Tärkeänä kumppanina hankkeessa olivat yhteistyöviljelijät, joiden kanssa kehitettiin ympäristöneuvontaa ja toteutettiin kokeilutoimintaa. Hankkeen toiminta-alueena oli Satakunta ja Varsinais-Suomi, mutta hankkeen tulokset ovat valtakunnallisesti hyödynnettävissä. Valtakunnallista näkemystä haettiin tiiviillä yhteistyöllä eri maakuntien toimijoiden kanssa. Tähän loppuraporttiin on koottu hankkeen kokemuksia ja tuloksia ympäristöneuvonnasta, ympäristöneuvojien koulutuksesta, tilakäynnistä ja viljelijöiden antamasta palautteesta ympäristöneuvonnasta, vedenlaadun seurannan kehittämisestä, kokeilutoiminnasta sekä hanketyöstä.Projektet TEHO Plus – Effektivering av vattenskyddet inom jordbruket, var en fortsättning på arbetet som påbörjats inom TEHO-projektet för åren 2011–2014. Tyngdpunkterna inom projektet har varit att ta fram ett utbildningspaket för miljörådgivarna inom jordbruket och att testa utbildningen, att ge gårdsspecifik rådgivning och dra nytta av erfarenheterna från den, att sätta samman ett informationspaket om miljöfrågorna inom jordbruket, att bedriva försöksverksamhet på gårdsnivå och att utveckla uppföljningen av vattenkvaliteten. I rådgivningen rekommenderades att miljöåtgärder riktas med hjälp av geodatamaterial och näringsbalanser. Projektet genomfördes som ett samarbete mellan NTM-centralen i Egentliga Finland, MTK i Satakunta och MTK i Egentliga Finland. Projektet finansierades av jord- och skogsbruksministeriet samt miljöministeriet. Viktiga samarbetspartner i projektet var de jordbrukare som hjälpte till att utveckla miljörådgivningen och bedrev försöksverksamheten. Projektet genomfördes i Satakunta och Egentliga Finland, men projektresultaten kan nyttjas i hela Finland. Genom nära samarbete med aktörer i de olika landskapen fick man in synpunkter från övriga landet. Denna slutrapport beskriver erfarenheterna och resultaten från projektet beträffande miljörådgivningen, utbildningen av miljörådgivare, besöken på gårdarna och jordbrukarnas respons på miljörådgivningen, utvecklingen av uppföljningen av vattenkvaliteten, försöksverksamheten och projektarbetet