Linear cryptanalysis of pseudorandom functions

Relatório de projeto de pesquisa.In this paper, we study linear relations propagating across block ciphers from the key input to the ciphertext (for a fixed plaintext block). This is a usual setting of a one-way function, used for instance in modes of operation such as KFB (key feedback). We instantiate the block cipher with the full 16-round DES and $s^2$-DES, 10-round LOKI91 and 24-round Khufu, for which linear relations with high bias are well known. Other interesting targets include the full 8.5-round IDEA and PES ciphers for which high bias linear relations exist under the assumption of weak keys. Consequences of these findings impact the security of modes of operation such as KFB and of pseudorandom number/bit generators. These analyses were possible due to the linear structure and the poor diffusion of the key schedule algorithms. These findings shall motivate carefull (re)design of current and future key schedule algorithms

Exposure of tropical ecosystems to artificial light at night: Brazil as a case study

Artificial nighttime lighting from streetlights and other sources has a broad range of biological effects. Understanding the spatial and temporal levels and patterns of this lighting is a key step in determining the severity of adverse effects on different ecosystems, vegetation, and habitat types. Few such analyses have been conducted, particularly for regions with high biodiversity, including the tropics. We used an intercalibrated version of the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP/OLS) images of stable nighttime lights to determine what proportion of original and current Brazilian vegetation types are experiencing measurable levels of artificial light and how this has changed in recent years. The percentage area affected by both detectable light and increases in brightness ranged between 0 and 35% for native vegetation types, and between 0 and 25% for current vegetation (i.e. including agriculture). The most heavily affected areas encompassed terrestrial coastal vegetation types (restingas and mangroves), Semideciduous Seasonal Forest, and Mixed Ombrophilous Forest. The existing small remnants of Lowland Deciduous and Semideciduous Seasonal Forests and of Campinarana had the lowest exposure levels to artificial light. Light pollution has not often been investigated in developing countries but our data show that it is an environmental concern

Multivariable control strategy for a bucket wheel reclaimer / Estratégia de controle multivariável de retomadora de roda de alcatruzes

Mining operations are generally done by large machines working in very harsh environments and historically having shy embedded technology. The use of control strategies, in many cases, dramatically increases the operating efficiency without large financial investments. In this context, this paper presents the method of choice and practical application of a multivariable control strategy for a bucket wheel ore reclaimer. This strategy adopts PI and PID controllers following a type override strategy acting on the manipulated variable: the slewing angular velocity. This manipulated variable was chosen because its actions affect the controlled variable very fast, so, allowing correcting disturbances in an adequate time. In addition, a fuzzy type controller was implemented to act on a second manipulated variable: the translation step. The second manipulated variable aims at taking the first one (angular speed) out of saturation states. When working together, these controllers seek to increase the equipment and process performance, taking into account, however, their operating limitations. Finally, a statistical analysis of results was performed in order to validate the feasibility of the implanted strategy when compared with the method previously in operation

O trabalho à procura de um direito: crise econômica, conflitos de classe e proteção social na Modernidade

The article reviews the milestones of economic and social history of the West, since the French Revolution, indicating the need for changes in the legal regulation of work. This is true particularly for Brazil, in which the legal frame devoted do labor regulation was established during the thirties of the 20th century. In order to determine the content and direction of legal change we need to take into account the factors that caused the decline of the Welfare State. And that on account of the fact that the Welfare State was not only the best known political project as one that came closest to reconcile democracy and income distribution.O artigo reexamina os marcos da história econômica e social do Ocidente, desde a Revolução Francesa, indicando a necessidade de mudanças na regulação jurídica do trabalho no presente. Particularmente para o Brasil, em que o modelo de regulação jurídica do trabalho foi instituído durante os anos 30 do século XX. Para determinar o conteúdo e o sentido da mudança jurídica necessitamos levar em conta os fatores que causaram o declínio do Welfare state. E isso em razão do fato de que o Welfare state foi não apenas o mais conhecido projeto político, como aquele que chegou mais perto de conciliar democracia e distribuição de renda

Estudo comparativo de métodos de dosagem para concretos de alta resistencia com o uso de materiais disponíveis na regiao Metropolitana de Curitiba

Orientador: Kleber Franke PortellaCo-orientadores: José Marques Filho e Sandro Eduardo da Silveira MendesDissertaçao (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduaçao em Construçao Civil. Defesa: Curitiba, 2005Inclui bibliografi

Fine-needle Aspiration Biopsy For Breast Lesions: A Comparison Between Two Devices For Obtaining Cytological Samples

Context and Objective: Fine-needle aspiration biopsy has been accepted worldwide for breast lesions. However, some questions remain, including the appropriateness of the puncture method. The objective of this work was to compare aspirates obtained by the auto-vacuum device and by the syringe pistol holder. Design and Setting: Randomized trial for validation of diagnostic method, at Hospital das Clinicas do Universidade Federal de Goiás and Hospital Araújo Jorge, Goiânio. Methods: 351 patients presenting breast lumps underwent fine-needle aspiration biopsy, either with the auto-vacuum device or the syringe pistol holder. A single cytopathologist analyzed all of the cytology slides. The rates of insufficient material, cellularity, cell distortion and background hemorrhage were evaluated. Results: The percentages of insufficient material were 16% and 22% (p = 0.18), for the auto-vacuum and pistol aspirates, respectively. Good cellularity was seen in 34% of autovacuum and 29% of pistol samples (p = 0.4). Cell distortion was seen in 31 and 26 cases, respectively (p = 07). Background hemorrhage occurred in 63 (35%) and 54 cases (31%) (p = 0.2), for auto-vacuum and pistol. The sensitivity was 88% and 86%; specificity 99% and 100%, positive predictive value 96% and and 100%, negative predictive value 96% and 95% and total occuracy 76% and 75% for the auto-vacuum and pistol, respectively. Conclusion: The results obtained from the two fine-needle aspiration biopsy methods were equivalent. Therefore, the auto-vacuum device is a good option for obtaining aspirates for cytology.1236271276Catania, S., Ciatto, S., Breast cytology: Instruments and technique (1992) Breast Cytology in Clinical Practice, pp. 11-60. , In: Ciatto S, editor. London: Martin DunitzDe Freitas Jr., R., Hamed, H., Fentiman, I., Fine needle aspiration cytology of palpable breast lesions (1992) Br J Clin Pract, 46 (3), pp. 187-190Franzen, S., Zajicek, J., Aspiration biopsy in diagnosis of palpable lesions of the breast. Critical review of 3479 consecutive biopsies Acta (1968) Radiol Ther Phys Biol, 7 (4), pp. 241-262Souza, J.A., Freitas Jr., R., Moreita, M.A.R., Philocreon, G.R., Acurácia da sensação tátil da PAAF no diagnóstico de less̄ocs mamárias (1995) Rev Bras Mastologia, 5 (3), pp. 7-10Freitas Júnior, R., Hamed, H., Millis, R.R., Tomas, N.M.A., Fentiman, I.S., Fine needle aspiration of breast lesions using auto-vacuum dispositive (1996) Rev Bras Mastologia, 6 (3), pp. 126-128de Freitas Júnior, R., Giraldo, P.C., Rerrori, O., Vieira-Matos, A.N., Tambascia, J.K., Fine needle aspiration biopsy of solid tumours by auto-vacuum system: A study in rats (1992) Eur J Surg Oncol, 18 (6), pp. 605-607Boccato, P., How to treat the aspirated material (1992) Breast Cytology in Clinical Practice, pp. 61-64. , In: Ciatto, S, editor London: Martin Dunitz(1987) International Union Against Cancer, , UICC. TNM classification of malignant tumors. Berlin: Springer-Verlag(1982) Am J Clin Pathol, 78 (6), pp. 806-816. , The World Health Organization Histological Typing of Breast Tumors - Second Edition. The World OrganizationGelabert, H.A., Hsiu, J.G., Mullen, J.T., Jaffe, A.H., D'Amato, N.A., Prospective evaluation of the rate of fine-needle aspiration biopsy in the diagnosis and management of patiencs with palpable solid breast lesions (1990) Am Surg, 56 (4), pp. 263-267Rouquayrol, M.Z., Epidemiologia e saúde (1988), Rio de Janeiro: Medsi - Editora CientíficaRoberts, J.C., Rainsbury, R.M., 'Tactile sensation: A new clinical sign during fine needle aspiration of breast lumps Ann (1994) R Coll Surg Eng, 76 (2), pp. 136-138Henderson, M.A., McCready, D.R., A simple technique for fine needle aspiration cytology (1994) J Am Coll Surg, 179 (4), pp. 471-473Sasaki, J., Izu, K., Automatic fine needle aspiration pistol specially designed for small tumors (1998) Acta Cytol, 42 (3), pp. 829-830Tao, L.C., Smith, J.W., Fine-needle aspiration biopsy using a newly-developed pencil-grip syringe holder (1999) Diagn Cytopathol, 20 (2), pp. 99-104Parel, J.J., Garrell, P.C., Smallwood, J.A., Fine needle aspiration cytology of breast masses: An evaluation of its accuracy and reasons for diagnostic failure (1987) Ann R Coll Surg Engl, 69 (4), pp. 156-159Abele, J., Stanley, M.W., Rollnis, S.D., Miller, T.R., What constitutes an adequate smear in fine-needle aspiration cytology of the breast? (1998) Cancer, 84 (1), pp. 57-61Zajdela, A., Ghossein, N.A., Pilleron, J.P., Ennuyer, A., The value of aspiration cytology in the diagnosis of breast cancer: Experience at the Fondation Curie (1975) Cancer, 35 (2), pp. 499-506Layfield, L.J., Dodd, L.G., Cytologically low grade malignancies: An important interpretative pitfall responsible for false negative diagnoses in fine-needle aspiration of the breast (1996) Diagn Cytopathol, 15 (3), pp. 250-259Feichter, G.E., Haberthür, F., Gobat, S., Dalquen, P., Breast cytology. Statistical analysis and cytohistologic correlations (1997) Acta Cytol, 41 (2), pp. 327-332Arisio, R., Cuccorese, C., Accinelli, G., Mano, M.P., Bordon, R., Fessia, L., Role of fine-needle aspiration biopsy in breast lesions: Analysis of a series of 4,110 cases (1998) Diagn Cytopathol, 18 (6), pp. 462-467Ariga, R., Bloom, K., Reddy, V.B., Fine-needle aspiration of clinically suspicious palpable breast masses with histopathologic correlation (2002) Am J Surg, 184 (5), pp. 410-41

Caracterização da resistência para acaricidas no carrapato Boophilus microplus*

Boophilus microplus  é um ectoparasita hematófago de bovinos, presente em áreas tropicais e subtropicais no mundo. É causador de enormes perdas econômicas pela espoliação que causa ao hospedeiro, além de ser transmissor de Anaplasma sp. e Babesia spp. O principal método de controle utilizado atualmente é o controle químico, que, embora eficiente, é caro, causa danos ao meio ambiente e deixa resíduos na carne. Além disso, é crescente o número de relatos que apontam um aumento das populações resistentes de carrapatos a diversos princípios químicos presentes nos acaricidas. As bases moleculares da resistência em Boophilus microplus ainda não são claramente conhecidas, mas muitos estudos indicam alguns dos mecanismos. Diferentes grupos de enzimas presentes em diferentes rotas metabólicas compõem os mecanismos de resistência e detoxificação celular, além de uma série de mutações que podem aumentar a tolerância a um determinado composto químico. Neste momento, outros tipos de controle, como o biológico e o imunológico estão sendo trabalhados para evitar a resistência nas populações de carrapato. No entanto, o controle biológico ainda não é viável para grandes rebanhos e a proteção induzida por vacinas não é suficiente para permitir o controle do B. microplus. O estudo dos mecanismos de resistência no carrapato pode ser de fundamental importância para seu controle em rebanhos