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A Comparison of Second Grade Children's Learning Curves on School Tasks with Their Respective Performances on the "Black Box Test of Learning Ability"Knox, Robert Stephen 01 May 1975 (has links)
This study investigated the usefulness of the Black Box Test of Learning Ability as an indicator of children's performance on math and writing tasks. Twelve second grade students, seven to eight years of age, demonstrated naivete on both tasks and were subsequently individually administered the learning test. The subjects were divided into two groups, and each group received a different task presentation order. Composite scores were derived for all subjects and tasks, and individual learning curves were compared.
The combined Black Test score produced a significantly high correlate to math (rho = .733) and writing (rho = .841) than either the paired associate or sequential learning tasks alone. Although the length of the learning curve of the BBT was indicative of the learning curve lengths for each school task, trial by trial learning curve comparisons were less reliable. Analysis of these data suggested that the method of instruction (i.e., the amount of attempted practice and appropriate feedback) was the major factor correlating the Black Box Test to each school task. It was suggested that the most useful assessment of "learning ability" would employ a behavioral sample of the task itself, rather than utilize a correlated activity.
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Approaches for Automated Software Security EvaluationsPoller, Andreas 23 October 2006 (has links) (PDF)
As a consequence of the highly increasing cross-linking of computer systems in computer networks, the possibilities for accessing programs operated at these machines is becoming more and more independent from the possibilities of having physical access to them. Thus the former existing physical access controls have to be replaced by logical access controls which ensure that computer systems are only used for the intended purpose and that the stored data are handled securely and confidentially.
The efficiency of such logical protection mechanism is verified by applying software security tests. During such tests it is proved whether security functions can be bypassed especially by exploiting software errors.
In this diploma thesis approaches for the automation of software security tests are examined regarding their effectiveness and applicability. The results are used to introduce a requirement and evaluation model for the qualitative analysis of such security evaluation automation approaches.
Additionally, the assertion is made that a highly automated software security evaluation is not a sensible development goal referring to the estimated cost-benefit ratio which is gained by trying to realise this goal. Based on this assertion, this diploma thesis discusses how to join the capabilities of a human tester and a software evaluation assistance system in an efficient test process.
Based on this considerations, the design and implementation of a software security evaluation system which has been developed prototypically for this diploma thesis is described. This system significantly involves the human tester in the evaluation process but provides approaches for automation where possible. Furthermore this proof-of-concept prototype is evaluated regarding its practical applicability. / Durch die zunehmende starke Vernetzung von Computertechnologie wird die Möglichkeit des Zugriffs auf einzelne Computersysteme und den darauf ablaufenden Programmen zunehmend ebenso stark unabhängig von den physischen Zugangsmöglichkeiten des Zugreifenden zu diesen Systemen. Diese wegfallenden physischen Zugangsbarrieren müssen deshalb durch logische Zugriffsbeschränkungen ersetzt werden, die sicherstellen, dass Computersysteme nur zu den vorgesehen Zwecken verwendet und die darin gespeicherten Daten sicher und vertraulich verarbeitet werden.
Die Wirksamkeit dieser logischen Schutzmechanismen wird mit Hilfe von s.g. Softwaresicherheitstests verifiziert. Dabei wird insbesondere überprüft, inwiefern Schutzfunktionen durch Zuhilfenahme von in der Software vorhandenen Programmfehlern umgangen werden können.
Diese Diplomarbeit überprüft bestehende Ansätze für die Automatisierung solcher Sicherheitstests hinsichtlich ihrer Wirksamkeit und Anwendbarkeit. Aus den Resultaten dieser Untersuchung wird ein allgemeines Anforderungs- und Bewertungsmodell entwickelt, welches die qualitative Bewertung von Ansätzen zur Sicherheitstestautomatisierung zulässt.
Desweiteren wird die Behauptung aufgestellt, dass die Forderung nach einer zu starken Automatisierung des Testverfahrens sich ungünstig gegenüber des Kosten-Nutzen-Verhältnisses auswirkt, welches bei der Realisierung dieser Forderungen zu erwarten ist. Darauf aufbauend versucht die Diplomarbeit abzugrenzen, wie sich die Fähigkeiten des menschlichen Testers und eines teilautomatisierbaren Softwaresystems effizient in einem Sicherheitstestprozess verbinden lassen.
Basierend auf diesen Betrachtungen wird beschrieben, wie ein Sicherheitsevaluierungssystem, welches prototypisch für diese Diplomarbeit entwickelt wurde, den Menschen zur Erstellung von Testalgorithmen einbindet aber, wenn dies zweckmäßig ist, Automatisierungen ermöglicht. Dieses System wird daraufhin auf seine praktische Anwendbarkeit untersucht.
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Possível envolvimento do monóxido de carbono na modulação do comportamento emocional em ratos: o papel do locus coeruleus / Involvement of carbono monoxide in the emotional behavior in rats: role of the locus coeruleus.Cazuza, Rafael Alves 03 March 2017 (has links)
O gás monóxido de carbono (CO) possui diversas funções no sistema nervoso central (SNC) funcionando como neuromodulador, como por exemplo da regulação da temperatura corporal, da nocicepção e mais recentemente, do comportamento emocional. Este neuromodulador gasoso é produzido pela ação da enzima heme oxigenase (HO), a qual é encontrada em diferentes áreas do SNC. Com destaque, esta enzima tem alta expressão no locus coeruleus (LC), o que sugere o envolvimento do CO na modulação de funções desempenhadas por esta estrutura. O LC localiza-se na ponte, sendo a maior origem da inervação noradrenérgica do SNC. Esta estrutura tem participação ativa na modulação das respostas relacionadas ao estresse, em particular, na modulação do comportamento emocional, desde que integra o Sistema de Inibição Comportamental (SIC), o qual inclui ainda o sistema septo-hipocampal e os núcleos da rafe. O SIC é responsável por comandar respostas defensivas de avaliação de risco, alerta e atenção, as quais podem ser eliciadas pela ansiedade. Dentro desta perspectiva, o presente estudo teve como objetivo avaliar se a ativação sistêmica da via HO-CO pode modular o comportamento emocional de ratos, e se há participação do LC. Assim, este trabalho avaliou se o tratamento sistêmico via intraperitoneal (i.p.) agudo (3 h antes) ou crônico (10 dias/2 vezes ao dia) com um liberador de monóxido de carbono (CORM-2), ou com indutor da enzima HO (CoPP), altera as respostas comportamentais no teste do labirinto em cruz elevado (LCE) e no teste claro-escuro (TCE) em ratos, bem como a expressão da enzima HO no LC. Em uma segunda etapa foi avaliado se a administração aguda de CORM-2 ou CoPP altera o comportamento avaliado no LCE e no TCE de ratos submetidos ao estresse crônico variado (ECV) por 10 dias. Os resultados mostraram que o CO induzido pela administração aguda ou crônica de CORM-2 ou CoPP possui efeito ansiolítico. Ainda, o tratamento com CORM-2 ou CoPP aumentou a expressão da enzima HO-1 em células localizadas no LC, sem alterar a imunorreatividade à enzima HO-2. Considerando os grupos submetidos ao estresse ECV, nem a ativação da via HO-CO ou o ECV apresentaram efeitos significativos nos comportamentos avaliados nos testes LCE e TCE. Os resultados do presente estudo sugerem que o tratamento sistêmico com drogas que modulam a liberação de CO possui claro efeito ansiolítico. Assim, é possível que o CO possa ser uma droga com potencial terapêutico para o tratamento de desordens neuropsiquiátricas. / The carbon monoxide gas (CO) has several functions in the central nervous system acting as a neuromodulator, such as in the body temperature regulation, nociception and more recently, in the emotional behavior modulation. This gas is produced by the action of the heme oxigenase enzyme (HO), which is found in different areas of the central nervous system (CNS). It is important to note that this enzyme has high expression in the locus coeruleus (LC), suggesting the involvement of CO in the modulation functions performed by this midbrain structure. LC is located in the pons, being the source of majority of the noradrenergic innervation of the CNS. This structure is intimately involved in the stress modulation responses, particularly in the emotional behavior regulation, since it integrates the Behavioral Inhibition System (BIS), which also includes septum-hippocampal system and raphe nucleus. The BIS is responsible for defensive responses like the risk assessment and alertness trigged by anxiety. Within this perspective, the present study was designed to evaluate whether the systemic HO-CO pathway can modulate emotional behavior of rats, and if the HO enzyme of the neurons located into LC is involved in this response. Thus, this study evaluated whether the acute systemic i.p. treatment (3 hours before) or chronic (10 days / 2 times a day) with a carbon monoxide releaser (CORM-2) or inducer of heme enzyme oxygenase (CoPP), is able to alter the behavioral responses in the elevated plus maze (EPM) and in the light-dark box test (LDB) in rats, and the HO enzyme expression in the LC. Furthermore, the effect of the acute administration of CORM-2 or CoPP was evaluated in the emotional behavior assessed in the EPM and LDB by rats submitted to unpredictable chronic stress (during 10 days). The results showed that the CO induced by acute or chronic administration of CORM-2 or CoPP has an anxiolytic-like effect. Furthermore, treatment with CORM-2 or CoPP promoted an increase of HO-1 enzyme expression in cells located in the LC without altering the immunoreactivity of HO-2 enzyme. Still, considering the rats subjected to stress UCS neither the activation of HO-CO pathway nor the UCS protocol altered the emotional behavior evaluated in the EPM and LDB tests. The results of this study suggest that systemic treatment with drugs that modulate the CO release has anxiolytic effect. Thus, it is possible that CO can be a potential drug therapeutic target for neuropsychiatric disorders.
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MODELLING AND FORECASTING INFLATION RATES IN GHANA: AN APPLICATION OF SARIMA MODELSAIDOO, ERIC January 2010 (has links)
Ghana faces a macroeconomic problem of inflation for a long period of time. The problem in somehow slows the economic growth in this country. As we all know, inflation is one of the major economic challenges facing most countries in the world especially those in African including Ghana. Therefore, forecasting inflation rates in Ghana becomes very important for its government to design economic strategies or effective monetary policies to combat any unexpected high inflation in this country. This paper studies seasonal autoregressive integrated moving average model to forecast inflation rates in Ghana. Using monthly inflation data from July 1991 to December 2009, we find that ARIMA (1,1,1)(0,0,1)12 can represent the data behavior of inflation rate in Ghana well. Based on the selected model, we forecast seven (7) months inflation rates of Ghana outside the sample period (i.e. from January 2010 to July 2010). The observed inflation rate from January to April which was published by Ghana Statistical Service Department fall within the 95% confidence interval obtained from the designed model. The forecasted results show a decreasing pattern and a turning point of Ghana inflation in the month of July.
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Efeito antidepressivo e ansiolítico do extrato metanólico de Hibiscus tiliaceus em modelo animal de depressão pós-partoAlmeida, Eduardo Farina de January 2012 (has links)
Hibiscus tiliaceus L. (Malvaceae) é usado popularmente em desordens do pós-parto. O extrato metanólico de flores de H. tiliaceus apresentou atividade antidepressiva-like nos testes de nado forçado e de suspensão da cauda, ambos são amplamente usados como modelos animais preditivos da atividade antidepressiva. Além disso, o extrato demonstrou uma tendência de aumento do tempo gasto nos braços abertos no labirinto em cruz elevado. Considerando que o extrato de H. tiliaceus, que contém fitoesteróis como o estigmasterol, o stigmastadienol e o stigmastadienone, pode ser útil no tratamento ou prevenção da depressão pós-parto relacionadas à retirada crônica de altos níveis de hormônios associados à gestação. Nosso objetivo foi avaliar o efeito de extratos de H. tiliaceus em modelo animal de depressão pós-parto e ansiedade. Utilizamos ratas Wistar fêmeas submetidas ao modelo de depressão pós-parto induzido por hormônios (estradiol e progesterona), administrados por via subcutânea. Após período gestacional induzido, os animais receberam água, veiculo ou extrato de H. tiliaceus nas doses de 100 e 400mg/kg, via oral (gavagem). No período pós-parto, as ratas foram submetidas a testes comportamentais de nado forçado, o labirinto em cruz elevado e de preferência claro-escuro como modelos preditivo de depressão e ansiedade. Foi obsevado um aumento no tempo de imobilidade associado a uma diminuição na tentativa de fuga, no teste do nado forçado, em animais submetidos ao modelo de depressão pós-parto comparado ao grupo controle, sugerindo que este modelo é capaz reproduzir sintomas de depressão pós-parto. Não houve diferença significativa nos testes de ansiedade entre os animais submetidos ao modelo de depressão pós-parto comparado aos controles. A administração de extrato metanólico de H. tiliaceus não foi capaz de alterar o comportamento relacionado à depressão e ansiedade em ratas Wistar. / Postpartum affective disorders are rarely modeled. The depressive-like behavior of hormone withdrawal following hormone-simulated "pregnancy" was described in Long-Evans and Sprague Dawley rats. Our aim was to evaluate the validity of hormone withdrawal following hormonesimulated "pregnancy" method in Wistar rats as a model of depression and/or anxiety. Recently, it was demonstrated an antidepressant-like profile of methanol extract of Hibiscus tiliaceus L., a plant used in postpartum disorders, in adult male Swiss albino mice, then, we also investigated the antidepressant and anxiolytic-like activities of the methanol extract of H. tiliaceus flowers using this animal model of postpartum disorder. Ovariectomized rats received daily injections of the vehicle or hormones (estradiol and progesterone) to simulate the 23-day gestational period in the rat. Days 24-27 were considered the ''post-partum'' period, where the methanolic extract of H. tiliaceus or vehicle were administered by gavage. Rats were submitted to forced swimming, elevated plus-maze test and lightdark box tests. Rats submitted to ''post-partum depression model'' increased the immobility time in forced swimming. The methanolic extract of H. tiliaceus administration did not alter the immobility time in the forced swim test. In the light-dark box test, rats submitted to post-partum depression model showed decreases in number of rearing in dark compartment. In conclusion, our data indicate that Wistar rats may be an adequate model postpartum affective disorders, showing ''depressive-like'' symptoms in the forced swim test without any anxiogenic effect. Besides, we could suggest that decrease on number of rearing in the dark compartment may indicate the motivational state.
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Possível envolvimento do monóxido de carbono na modulação do comportamento emocional em ratos: o papel do locus coeruleus / Involvement of carbono monoxide in the emotional behavior in rats: role of the locus coeruleus.Rafael Alves Cazuza 03 March 2017 (has links)
O gás monóxido de carbono (CO) possui diversas funções no sistema nervoso central (SNC) funcionando como neuromodulador, como por exemplo da regulação da temperatura corporal, da nocicepção e mais recentemente, do comportamento emocional. Este neuromodulador gasoso é produzido pela ação da enzima heme oxigenase (HO), a qual é encontrada em diferentes áreas do SNC. Com destaque, esta enzima tem alta expressão no locus coeruleus (LC), o que sugere o envolvimento do CO na modulação de funções desempenhadas por esta estrutura. O LC localiza-se na ponte, sendo a maior origem da inervação noradrenérgica do SNC. Esta estrutura tem participação ativa na modulação das respostas relacionadas ao estresse, em particular, na modulação do comportamento emocional, desde que integra o Sistema de Inibição Comportamental (SIC), o qual inclui ainda o sistema septo-hipocampal e os núcleos da rafe. O SIC é responsável por comandar respostas defensivas de avaliação de risco, alerta e atenção, as quais podem ser eliciadas pela ansiedade. Dentro desta perspectiva, o presente estudo teve como objetivo avaliar se a ativação sistêmica da via HO-CO pode modular o comportamento emocional de ratos, e se há participação do LC. Assim, este trabalho avaliou se o tratamento sistêmico via intraperitoneal (i.p.) agudo (3 h antes) ou crônico (10 dias/2 vezes ao dia) com um liberador de monóxido de carbono (CORM-2), ou com indutor da enzima HO (CoPP), altera as respostas comportamentais no teste do labirinto em cruz elevado (LCE) e no teste claro-escuro (TCE) em ratos, bem como a expressão da enzima HO no LC. Em uma segunda etapa foi avaliado se a administração aguda de CORM-2 ou CoPP altera o comportamento avaliado no LCE e no TCE de ratos submetidos ao estresse crônico variado (ECV) por 10 dias. Os resultados mostraram que o CO induzido pela administração aguda ou crônica de CORM-2 ou CoPP possui efeito ansiolítico. Ainda, o tratamento com CORM-2 ou CoPP aumentou a expressão da enzima HO-1 em células localizadas no LC, sem alterar a imunorreatividade à enzima HO-2. Considerando os grupos submetidos ao estresse ECV, nem a ativação da via HO-CO ou o ECV apresentaram efeitos significativos nos comportamentos avaliados nos testes LCE e TCE. Os resultados do presente estudo sugerem que o tratamento sistêmico com drogas que modulam a liberação de CO possui claro efeito ansiolítico. Assim, é possível que o CO possa ser uma droga com potencial terapêutico para o tratamento de desordens neuropsiquiátricas. / The carbon monoxide gas (CO) has several functions in the central nervous system acting as a neuromodulator, such as in the body temperature regulation, nociception and more recently, in the emotional behavior modulation. This gas is produced by the action of the heme oxigenase enzyme (HO), which is found in different areas of the central nervous system (CNS). It is important to note that this enzyme has high expression in the locus coeruleus (LC), suggesting the involvement of CO in the modulation functions performed by this midbrain structure. LC is located in the pons, being the source of majority of the noradrenergic innervation of the CNS. This structure is intimately involved in the stress modulation responses, particularly in the emotional behavior regulation, since it integrates the Behavioral Inhibition System (BIS), which also includes septum-hippocampal system and raphe nucleus. The BIS is responsible for defensive responses like the risk assessment and alertness trigged by anxiety. Within this perspective, the present study was designed to evaluate whether the systemic HO-CO pathway can modulate emotional behavior of rats, and if the HO enzyme of the neurons located into LC is involved in this response. Thus, this study evaluated whether the acute systemic i.p. treatment (3 hours before) or chronic (10 days / 2 times a day) with a carbon monoxide releaser (CORM-2) or inducer of heme enzyme oxygenase (CoPP), is able to alter the behavioral responses in the elevated plus maze (EPM) and in the light-dark box test (LDB) in rats, and the HO enzyme expression in the LC. Furthermore, the effect of the acute administration of CORM-2 or CoPP was evaluated in the emotional behavior assessed in the EPM and LDB by rats submitted to unpredictable chronic stress (during 10 days). The results showed that the CO induced by acute or chronic administration of CORM-2 or CoPP has an anxiolytic-like effect. Furthermore, treatment with CORM-2 or CoPP promoted an increase of HO-1 enzyme expression in cells located in the LC without altering the immunoreactivity of HO-2 enzyme. Still, considering the rats subjected to stress UCS neither the activation of HO-CO pathway nor the UCS protocol altered the emotional behavior evaluated in the EPM and LDB tests. The results of this study suggest that systemic treatment with drugs that modulate the CO release has anxiolytic effect. Thus, it is possible that CO can be a potential drug therapeutic target for neuropsychiatric disorders.
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Efeito antidepressivo e ansiolítico do extrato metanólico de Hibiscus tiliaceus em modelo animal de depressão pós-partoAlmeida, Eduardo Farina de January 2012 (has links)
Hibiscus tiliaceus L. (Malvaceae) é usado popularmente em desordens do pós-parto. O extrato metanólico de flores de H. tiliaceus apresentou atividade antidepressiva-like nos testes de nado forçado e de suspensão da cauda, ambos são amplamente usados como modelos animais preditivos da atividade antidepressiva. Além disso, o extrato demonstrou uma tendência de aumento do tempo gasto nos braços abertos no labirinto em cruz elevado. Considerando que o extrato de H. tiliaceus, que contém fitoesteróis como o estigmasterol, o stigmastadienol e o stigmastadienone, pode ser útil no tratamento ou prevenção da depressão pós-parto relacionadas à retirada crônica de altos níveis de hormônios associados à gestação. Nosso objetivo foi avaliar o efeito de extratos de H. tiliaceus em modelo animal de depressão pós-parto e ansiedade. Utilizamos ratas Wistar fêmeas submetidas ao modelo de depressão pós-parto induzido por hormônios (estradiol e progesterona), administrados por via subcutânea. Após período gestacional induzido, os animais receberam água, veiculo ou extrato de H. tiliaceus nas doses de 100 e 400mg/kg, via oral (gavagem). No período pós-parto, as ratas foram submetidas a testes comportamentais de nado forçado, o labirinto em cruz elevado e de preferência claro-escuro como modelos preditivo de depressão e ansiedade. Foi obsevado um aumento no tempo de imobilidade associado a uma diminuição na tentativa de fuga, no teste do nado forçado, em animais submetidos ao modelo de depressão pós-parto comparado ao grupo controle, sugerindo que este modelo é capaz reproduzir sintomas de depressão pós-parto. Não houve diferença significativa nos testes de ansiedade entre os animais submetidos ao modelo de depressão pós-parto comparado aos controles. A administração de extrato metanólico de H. tiliaceus não foi capaz de alterar o comportamento relacionado à depressão e ansiedade em ratas Wistar. / Postpartum affective disorders are rarely modeled. The depressive-like behavior of hormone withdrawal following hormone-simulated "pregnancy" was described in Long-Evans and Sprague Dawley rats. Our aim was to evaluate the validity of hormone withdrawal following hormonesimulated "pregnancy" method in Wistar rats as a model of depression and/or anxiety. Recently, it was demonstrated an antidepressant-like profile of methanol extract of Hibiscus tiliaceus L., a plant used in postpartum disorders, in adult male Swiss albino mice, then, we also investigated the antidepressant and anxiolytic-like activities of the methanol extract of H. tiliaceus flowers using this animal model of postpartum disorder. Ovariectomized rats received daily injections of the vehicle or hormones (estradiol and progesterone) to simulate the 23-day gestational period in the rat. Days 24-27 were considered the ''post-partum'' period, where the methanolic extract of H. tiliaceus or vehicle were administered by gavage. Rats were submitted to forced swimming, elevated plus-maze test and lightdark box tests. Rats submitted to ''post-partum depression model'' increased the immobility time in forced swimming. The methanolic extract of H. tiliaceus administration did not alter the immobility time in the forced swim test. In the light-dark box test, rats submitted to post-partum depression model showed decreases in number of rearing in dark compartment. In conclusion, our data indicate that Wistar rats may be an adequate model postpartum affective disorders, showing ''depressive-like'' symptoms in the forced swim test without any anxiogenic effect. Besides, we could suggest that decrease on number of rearing in the dark compartment may indicate the motivational state.
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Efeito antidepressivo e ansiolítico do extrato metanólico de Hibiscus tiliaceus em modelo animal de depressão pós-partoAlmeida, Eduardo Farina de January 2012 (has links)
Hibiscus tiliaceus L. (Malvaceae) é usado popularmente em desordens do pós-parto. O extrato metanólico de flores de H. tiliaceus apresentou atividade antidepressiva-like nos testes de nado forçado e de suspensão da cauda, ambos são amplamente usados como modelos animais preditivos da atividade antidepressiva. Além disso, o extrato demonstrou uma tendência de aumento do tempo gasto nos braços abertos no labirinto em cruz elevado. Considerando que o extrato de H. tiliaceus, que contém fitoesteróis como o estigmasterol, o stigmastadienol e o stigmastadienone, pode ser útil no tratamento ou prevenção da depressão pós-parto relacionadas à retirada crônica de altos níveis de hormônios associados à gestação. Nosso objetivo foi avaliar o efeito de extratos de H. tiliaceus em modelo animal de depressão pós-parto e ansiedade. Utilizamos ratas Wistar fêmeas submetidas ao modelo de depressão pós-parto induzido por hormônios (estradiol e progesterona), administrados por via subcutânea. Após período gestacional induzido, os animais receberam água, veiculo ou extrato de H. tiliaceus nas doses de 100 e 400mg/kg, via oral (gavagem). No período pós-parto, as ratas foram submetidas a testes comportamentais de nado forçado, o labirinto em cruz elevado e de preferência claro-escuro como modelos preditivo de depressão e ansiedade. Foi obsevado um aumento no tempo de imobilidade associado a uma diminuição na tentativa de fuga, no teste do nado forçado, em animais submetidos ao modelo de depressão pós-parto comparado ao grupo controle, sugerindo que este modelo é capaz reproduzir sintomas de depressão pós-parto. Não houve diferença significativa nos testes de ansiedade entre os animais submetidos ao modelo de depressão pós-parto comparado aos controles. A administração de extrato metanólico de H. tiliaceus não foi capaz de alterar o comportamento relacionado à depressão e ansiedade em ratas Wistar. / Postpartum affective disorders are rarely modeled. The depressive-like behavior of hormone withdrawal following hormone-simulated "pregnancy" was described in Long-Evans and Sprague Dawley rats. Our aim was to evaluate the validity of hormone withdrawal following hormonesimulated "pregnancy" method in Wistar rats as a model of depression and/or anxiety. Recently, it was demonstrated an antidepressant-like profile of methanol extract of Hibiscus tiliaceus L., a plant used in postpartum disorders, in adult male Swiss albino mice, then, we also investigated the antidepressant and anxiolytic-like activities of the methanol extract of H. tiliaceus flowers using this animal model of postpartum disorder. Ovariectomized rats received daily injections of the vehicle or hormones (estradiol and progesterone) to simulate the 23-day gestational period in the rat. Days 24-27 were considered the ''post-partum'' period, where the methanolic extract of H. tiliaceus or vehicle were administered by gavage. Rats were submitted to forced swimming, elevated plus-maze test and lightdark box tests. Rats submitted to ''post-partum depression model'' increased the immobility time in forced swimming. The methanolic extract of H. tiliaceus administration did not alter the immobility time in the forced swim test. In the light-dark box test, rats submitted to post-partum depression model showed decreases in number of rearing in dark compartment. In conclusion, our data indicate that Wistar rats may be an adequate model postpartum affective disorders, showing ''depressive-like'' symptoms in the forced swim test without any anxiogenic effect. Besides, we could suggest that decrease on number of rearing in the dark compartment may indicate the motivational state.
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Approaches for Automated Software Security EvaluationsPoller, Andreas 23 October 2006 (has links)
As a consequence of the highly increasing cross-linking of computer systems in computer networks, the possibilities for accessing programs operated at these machines is becoming more and more independent from the possibilities of having physical access to them. Thus the former existing physical access controls have to be replaced by logical access controls which ensure that computer systems are only used for the intended purpose and that the stored data are handled securely and confidentially.
The efficiency of such logical protection mechanism is verified by applying software security tests. During such tests it is proved whether security functions can be bypassed especially by exploiting software errors.
In this diploma thesis approaches for the automation of software security tests are examined regarding their effectiveness and applicability. The results are used to introduce a requirement and evaluation model for the qualitative analysis of such security evaluation automation approaches.
Additionally, the assertion is made that a highly automated software security evaluation is not a sensible development goal referring to the estimated cost-benefit ratio which is gained by trying to realise this goal. Based on this assertion, this diploma thesis discusses how to join the capabilities of a human tester and a software evaluation assistance system in an efficient test process.
Based on this considerations, the design and implementation of a software security evaluation system which has been developed prototypically for this diploma thesis is described. This system significantly involves the human tester in the evaluation process but provides approaches for automation where possible. Furthermore this proof-of-concept prototype is evaluated regarding its practical applicability. / Durch die zunehmende starke Vernetzung von Computertechnologie wird die Möglichkeit des Zugriffs auf einzelne Computersysteme und den darauf ablaufenden Programmen zunehmend ebenso stark unabhängig von den physischen Zugangsmöglichkeiten des Zugreifenden zu diesen Systemen. Diese wegfallenden physischen Zugangsbarrieren müssen deshalb durch logische Zugriffsbeschränkungen ersetzt werden, die sicherstellen, dass Computersysteme nur zu den vorgesehen Zwecken verwendet und die darin gespeicherten Daten sicher und vertraulich verarbeitet werden.
Die Wirksamkeit dieser logischen Schutzmechanismen wird mit Hilfe von s.g. Softwaresicherheitstests verifiziert. Dabei wird insbesondere überprüft, inwiefern Schutzfunktionen durch Zuhilfenahme von in der Software vorhandenen Programmfehlern umgangen werden können.
Diese Diplomarbeit überprüft bestehende Ansätze für die Automatisierung solcher Sicherheitstests hinsichtlich ihrer Wirksamkeit und Anwendbarkeit. Aus den Resultaten dieser Untersuchung wird ein allgemeines Anforderungs- und Bewertungsmodell entwickelt, welches die qualitative Bewertung von Ansätzen zur Sicherheitstestautomatisierung zulässt.
Desweiteren wird die Behauptung aufgestellt, dass die Forderung nach einer zu starken Automatisierung des Testverfahrens sich ungünstig gegenüber des Kosten-Nutzen-Verhältnisses auswirkt, welches bei der Realisierung dieser Forderungen zu erwarten ist. Darauf aufbauend versucht die Diplomarbeit abzugrenzen, wie sich die Fähigkeiten des menschlichen Testers und eines teilautomatisierbaren Softwaresystems effizient in einem Sicherheitstestprozess verbinden lassen.
Basierend auf diesen Betrachtungen wird beschrieben, wie ein Sicherheitsevaluierungssystem, welches prototypisch für diese Diplomarbeit entwickelt wurde, den Menschen zur Erstellung von Testalgorithmen einbindet aber, wenn dies zweckmäßig ist, Automatisierungen ermöglicht. Dieses System wird daraufhin auf seine praktische Anwendbarkeit untersucht.
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Languages, Tools and Patterns for the Specification of Distributed Real-Time Tests / Sprachen, Werkzeuge und Muster für die Spezifikation von verteilten Echtzeit-TestsNeukirchen, Helmut Wolfram 25 August 2004 (has links)
No description available.
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