703 resultados para TERRORIST ATTACKS


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Critical Infrastructures became more vulnerable to attacks from adversaries as SCADA systems become connected to the Internet. The open standards for SCADA Communications make it very easy for attackers to gain in-depth knowledge about the working and operations of SCADA networks. A number of Intenrnet SCADA security issues were raised that have compromised the authenticity, confidentiality, integrity and non-repudiation of information transfer between SCADA Components. This paper presents an integration of the Cross Crypto Scheme Cipher to secure communications for SCADA components. The proposed scheme integrates both the best features of symmetric and asymmetric encryptiontechniques. It also utilizes the MD5 hashing algorithm to ensure the integrity of information being transmitted.

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In the present work, we studied a common outbreaking Lepidoptera species in Portuguese pine stands – Thaumetopoea pityocampa (Den. & Schiff.) - and one of its potential predators – Parus major (L.). The population dynamics of the immature stages of the Lepidoptera was studied in several types of Pinus pinaster (Aiton) plantations in three different areas: Setúbal Peninsula, Abrantes and National Pine Forest of Leiria. Location and plantation structure was the most important factors determining population density of T. pityocampa. Setubal and Abrantes was highly susceptible to attacks by the Lepidoptera, whereas Leiria had lower densities. Young and homogeneous pine stands was more susceptible to attacks than older and more heterogeneous pines stands. However, a desynchronized population of T. pityocampa, in which the larvae develops during summer instead of during winter, reached high densities also in Leiria. The impact of several mortality factors and climatic conditions on the immature stages of the insect (eggs and larvae), in normal and desynchronized populations are discussed, as well as possible evolutionary implications of the sudden appearance of the new version of T. pityocampa. The break of the pupa diapause and adult emergence times the annual life cycle of this insect. Adults from the desynchronized population emerged earlier than adults from the normal population, which in turn determined the change in the larvae development period. Different factors, potentially affecting the timing of adult emergence in both normal and abnormal populations are also discussed. To study P. Major, nest-boxes were placed in the areas of Setúbal and Leiria and they were monitored during three seasons. The nest-boxes increased the density of breeding and wintering birds in the studied pine plantations, indicating that a lack of natural holes are in fact a limiting factor for this populations. The earliest breeding start for this species was recorded in my study area, indicating that Portuguese coastal pines provide good breeding conditions earlier than in other areas of Europe and North Africa. This leads to an overlap between the end of the larvae stage of T. pityocampa and the beginning of the breeding season of P. major. Key-words: Thaumetopoea pityocampa, Parus major, Pinus pinaster, population dynamics, Portugal.

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A crescente preocupação que envolve as questões ambientais a nível mundial, cada vez mais agravadas pelo comportamento irresponsável do Homem, conduziu à criação de métodos de avaliação dos impactes ambientais provocados por produtos e sistemas. Sendo o sector da construção responsável por grande parte desses impactes, é evidente a necessidade de aplicação de medidas que visem mitigar ou, no mínimo, reduzir até valores aceitáveis, essas agressões ao meio ambiente. Nesse âmbito, é natural que tenha surgido a ideia de aplicar uma metodologia tão precisa e rigorosa como a LCA ao sector da construção. No entanto, nos dias de hoje, as preocupações alargaram-se às vertentes social e económica que, juntamente com a vertente ambiental, formam o triângulo de equilíbrio do desenvolvimento sustentável. É precisamente essa avaliação tripartida que esta Dissertação pretende abordar, tentando aprofundar conhecimentos e fornecer alternativas, através da análise crítica, que possam contribuir para a melhoria contínua desta metodologia.

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Dissertação de Mestrado apresentada ao Instituto de Contabilidade e Administração do Porto para a obtenção de grau de Mestre em Auditoria, sob a orientação de Luís Silva Rodrigues

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Two clinical cases of patients who survived after numerous attacks of Africanized bees (600 and 1500 bee stings, respectively) are reported. Clinical manifestation was characterized by diffuse and widespread edema, a burning sensation in the skin, headache, weakness, dizziness, generalized paresthesia, somnolence and hypotension. Acute renal failure developed and was attributed to hypotension, intravascular hemolysis, myoglobinuria due to rhabdomyolysis and probably to direct toxic effect of the massive quantity of injected venom. They were treated with antihistaminic, corticosteroids and fluid infusion. One of them had severe acute renal failure and dialysis was required. No clinical complication was observed during hospital stay and complete renal function recovery was observed in both patients. In conclusion, acute renal failure after bee stings is probably due to pigment nephropathy associated with hypovolemia. Early recognition of this syndrome is crucial to the successful management of these patients.

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BACKGROUND: Atherosclerotic carotid disease represents approximately 20% of the causes of ischemic stroke. Effective treatment options, such as endovascular or surgical revascularization procedures, are available. Doppler Ultrasound (DUS) is a non-invasive, inexpensive, routine exam used to evaluate the presence of internal carotid artery (ICA) stenosis. We retrospectively analysed the prevalence of severe atherosclerotic carotid disease in a population of patients with acute ischemic stroke/transitory ischemic attacks (TIAs), and the role of DUS in the detection of ICA stenosis and treatment decisions in these patients. METHODS: A total of 318 patients with ischemic stroke or TIAs was admitted to our stroke unit, and 260 patients were studied by DUS. ICA stenosis was evaluated by DUS according to peak systolic velocity. All DUS exams were performed by the same operator. ICA stenosis was further assessed in 43 patients by digital subtraction angiography (DSA) using NASCET criteria. RESULTS: Of the total 318 patients, 260 (82%) had DUS evaluation. Of the total 520 ICAs studied by DUS, degrees of ICA stenosis were: 0-29% n= 438 (84%); 30-49% n= 8 (2%); 50-69% n= 27 (5%); 70-89% n= 15 (3%); 90-99% n= 20 (4%); oclusão n= 14 (2%). Of the total 260 patients studied, 43 (16.5%) underwent DSA. Sensibility and specificity of DUS in the diagnosis of carotid stenosis over 70% were, respectively, 91% e 84%. Of the total 31 patients with significant carotid stenosis (70-99%), 23 (74%) underwent subsequent carotid revascularization procedures. DISCUSSION: DUS is an important screening test in our stroke unit, justifying its use as a routine exam for all patients with ischemic stroke/TIAs. Moreover, our results show the relevance of severe carotid disease in a population with acute ischemic stroke/TIAs (16.5%), with a total of 9% of patients being submitted to carotid revascularization procedures.

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The objective of this report is to describe the first record of Desmodus rotundus in urban area from the city of Olinda, Pernambuco State, Northeastern Brazil, and to draw attention to the possible risk of rabies transmission in this place. After the complaint of a dog owner who observed three bats attacking his dog, images registering attacks of D. rotundus were captured with a video camera. From 09:00 p.m. on 13 February 2004 to 04:00 a.m. of the next day, a high frequency of haematophagic activity and the presence of several bites on the dog's body were observed. This finding represents a serious risk to public health. Thus, it is necessary to further study the bat fauna, with special attention to their feeding behaviour in this place, in order to better know their biology and to adopt pertinent control measures. This is, to our knowledge, the first record of D. rotundus in urban area of Olinda.

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Muitas instalações municipais são alvo de manutenção permanente, devido ao uso de produtos químicos que provocam a corrosão e degradação dos mais diversos materiais. Esta degradação acarreta custos elevados para os municípios e privação de uso de algumas instalações devido a manutenção curativa ou preventiva. Um estudo adequado do efeito dos produtos utilizados, poderia conduzir à utilização de materiais mais nobres, que aumentasse significativamente o tempo de vida dos produtos mais atacados pela degradação por corrosão, através de estudos que permitissem avaliar a relação custo-benefício e, caso esta fosse favorável, proceder à substituição de determinados componentes em materiais relativamente fracos, por outros com uma maior capacidade para resistir aos ataques produzidos pelo meio em que estão inseridos. Este estudo foi efectuado com vista a estudar a degradação de determinados materiais expostos essencialmente à acção do Cloro em instalações municipais, permitindo assim seleccionar novos materiais que permitissem uma vida útil dos componentes mais alargada, estudando convenientemente a relação custo-benefício. Foi possível observar que a introdução de alguns materiais mais nobres, poderá reduzir drasticamente as operações de manutenção, diminuindo os custos e reduzindo também o tempo de indisponibilidade dos equipamentos municipais.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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Muito se tem falado sobre revolução tecnológica e do aparecimento constante de novas aplicações Web, com novas funcionalidades que visam facilitar o trabalho dos utilizadores. Mas será que estas aplicações garantem que os dados transmitidos são tratados e enviados por canais seguros (protocolos)? Que garantias é que o utilizador tem que mesmo que a aplicação utilize um canal, que prevê a privacidade e integridade de dados, esta não apresente alguma vulnerabilidade pondo em causa a informação sensível do utilizador? Software que não foi devidamente testado, aliado à falta de sensibilização por parte dos responsáveis pelo desenvolvimento de software para questões de segurança, levam ao aumento de vulnerabilidades e assim exponenciam o número de potenciais vítimas. Isto aliado ao efeito de desinibição que o sentimento de invisibilidade pode provocar, conduz ao facilitismo e consequentemente ao aumento do número de vítimas alvos de ataques informáticos. O utilizador, por vezes, não sabe muito bem do que se deve proteger, pois a confiança que depõem no software não pressupõem que os seus dados estejam em risco. Neste contexto foram recolhidos dados históricos relativos a vulnerabilidades nos protocolos SSL/TLS, para perceber o impacto que as mesmas apresentam e avaliar o grau de risco. Para além disso, foram avaliados um número significativo de domínios portugueses para perceber se os mesmos têm uma vulnerabilidade específica do protocolo SSL/TLS.

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Hyperimmunoglobulinemia D and periodic fever syndrome (HIDS; MIM#260920) is a rare recessively-inherited autoinflammatory condition caused bymutations in the MVK gene, which encodes for mevalonate kinase, an essential enzyme in the isoprenoid pathway. HIDS is clinically characterized by recurrent episodes of fever and inflammation. Herewe report on the case of a 2 year-old Portuguese boy with recurrent episodes of fever, malaise, massive cervical lymphadenopathy and hepatosplenomegaly since the age of 12 months. Rash, arthralgia, abdominal pain and diarrhea were also seen occasionally. During attacks a vigorous acute-phase response was detected, including elevated erythrocyte sedimentation rate, C-reactive protein, serum amyloid A and leukocytosis. Clinical and laboratory improvement was seen between attacks. Despite normal serum IgD level, HIDS was clinically suspected. Mutational MVK analysis revealed the homozygous genotype with the novel p.Arg277Gly (p.R277G) mutation, while the healthy non consanguineous parents were heterozygous. Short nonsteroidal anti-inflammatory drugs and corticosteroid courses were given during attacks with poor benefits, where as anakinra showed positive responses only at high doses. The p.R277Gmutation here described is a novel missense MVK mutation, and it has been detected in this casewith a severe HIDS phenotype. Further studies are needed to evaluate a co-relation genotype, enzyme activity and phenotype, and to define the best therapeutic strategies.

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A malaria survey was conducted in an area of high transmission (Costa Marques, Rondonia, Brazil) to determine the prevalence of asymptomatic parasitemia and its clinical significance. Most of the people surveyed were immigrants who had lived in the endemic area < 5 years. The people had easy access to free diagnostic and treatment services at the Malaria Clinic in the town of Costa Marques. The prevalence of plasmodial parasitemia in 344 people was 22%. There were 36 individuals with asymptomatic infections among the 77 parasitemic patients. During the two days following the initial examination, 19 ofthe 36 individuals: with asymptomatic infections developed malaria. Among the 17 patients who remained asymptomatic for > 2 days, 4 had only gametocytes, 1 had taken inadequate anti-malarial treatment, 3 were under treatment and 2 moved. Six asymptomatic patients denied the use of anti-malarial drugs and they developed malaria 3-6 days after the initial parasitological diagnosis. The final patient remained asymptomatic during the 7 day observation period. He had a history of > 40 malaria attacks and denied the use of antimalarial treatment. With the exception of the latter all of the other asymptomatic patients, were either in the incubation period or had been treated It is concluded that asymptomatic malaria is rare in the Costa Marques area and that it is necessary to treat all individuals with plasmodial parasitemia.

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The hemorrhagic syndrome of leptospirosis was studied in guinea pigs. The study correlates hematological, histopathological and immunohistochemical alterations in sixty animals inoculated by the intraperitoneal route with lml of the culture of virulent strain of Leptospira interrogans serovar copenhageni. Leptospirae antigens were detected by immunoperoxidase, chiefly in liver, kidney and heart muscle capillaries. Possible pathogenic mechanisms responsible for hemorrhagic syndrome are discussed with emphasis on toxic and anoxic attacks causing damage to endothelia, platelet depletion and alterations to hemostasia rates: prothrombin time [FT], partial thromboplastin time [PIT] and fibrinogen concentrations. Tide clinical-laboratoiy picture is compatible with the histopathological observation of disseminated intravascular coagulation [D1C] in most of the guinea pigs from day 4 of infection.

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Dissertação para obtenção do Grau de Mestre em Engenharia Informática

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Outbreaks of attacks upon human beings by vampire bats seems to be a common phenomenon in several regions of Latin America, but the occurrence of rabies infection among humans bled by vampires, is relatively low. In the present study, two outbreaks of human rabies transmitted by common vampire bats (Desmodus rotundus) are described from Bahia State, Northeasthern Brazil, in 1991 and 1992. The first was recorded in Aporá where 308 people were bled by vampire bats and three of these die from this zoonosis. The 2nd outbreak occurred in Conde where only five people were bled by vampires, and two deaths by rabies were registered. Our data suggest that rabies transmitted by bats basically depends on the presence of virus in the vampire bat population and not on the number of humans bled by them.