Evaluation of analysis techniques for low frequency interior noise and vibration of commercial aircraft

The application of selected analysis techniques to low frequency cabin noise associated with advanced propeller engine installations is evaluated. Three design analysis techniques were chosen for evaluation including finite element analysis, statistical energy analysis (SEA), and a power flow method using element of SEA (computer program Propeller Aircraft Interior Noise). An overview of the three procedures is provided. Data from tests of a 727 airplane (modified to accept a propeller engine) were used to compare with predictions. Comparisons of predicted and measured levels at the end of the first year's effort showed reasonable agreement leading to the conclusion that each technique had value for propeller engine noise predictions on large commercial transports. However, variations in agreement were large enough to remain cautious and to lead to recommendations for further work with each technique. Assessment of the second year's results leads to the conclusion that the selected techniques can accurately predict trends and can be useful to a designer, but that absolute level predictions remain unreliable due to complexity of the aircraft structure and low modal densities

The Impact of the Foreign Investment in Real Property Tax Act of 1980 on International Tax Treaties

This thesis will focus on the problem of inconsistency between the new Act and contradictory treaty provisions in treaties with the Tax Haven Countries and Scandinavian Countries and seek possible solutions for such conflicts

Application of analysis techniques for low frequency interior noise and vibration of commercial aircraft

Finite element analysis (FEA), statistical energy analysis (SEA), and a power flow method (computer program PAIN) were used to assess low frequency interior noise associated with advanced propeller installations. FEA and SEA models were used to predict cabin noise and vibration and evaluate suppression concepts for structure-borne noise associated with the shaft rotational frequency and harmonics (less than 100 Hz). SEA and PAIN models were used to predict cabin noise and vibration and evaluate suppression concepts for airborne noise associated with engine radiated propeller tones. Both aft-mounted and wing-mounted propeller configurations were evaluated. Ground vibration test data from a 727 airplane modified to accept a propeller engine were used to compare with predictions for the aft-mounted propeller. Similar data from the 767 airplane was used for the wing-mounted comparisons

Dendritic cell quiescence during systemic inflammation driven by LPS stimulation of radioresistant cells in vivo

Dendritic cell (DC) activation is a prerequisite for T cell priming. During infection, activation can ensue from signaling via pattern-recognition receptors after contact with pathogens or infected cells. Alternatively, it has been proposed that DCs can be activated indirectly by signals produced by infected tissues. To address the contribution of tissue-derived signals, we measured DC activation in a model in which radioresistant cells can or cannot respond to lipopolysaccharide (LPS). We report that recognition of LPS by the radioresistant compartment is sufficient to induce local and systemic inflammation characterized by high circulating levels of tumor necrosis factor (TNF) α, interleukin (IL) 1β, IL-6, and CC chemokine ligand 2. However, this is not sufficient to activate DCs, whether measured by migration, gene expression, phenotypic, or functional criteria, or to render DC refractory to subsequent stimulation with CpG-containing DNA. Similarly, acute or chronic exposure to proinflammatory cytokines such as TNF-α ± interferon α/β has marginal effects on DC phenotype in vivo when compared with LPS. In addition, DC activation and migration induced by LPS is unimpaired when radioresistant cells cannot respond to the stimulus. Thus, inflammatory mediators originating from nonhematopoietic tissues and from radioresistant hematopoietic cells are neither sufficient nor required for DC activation in vivo

Papanicolaou test in Brazil: analysis of the National Health Survey of 2013 and 2019

OBJETIVOS: Comparar a cobertura do rastreamento do câncer de colo do útero no Brasil em 2013 e 2019, investigar os fatores associados à realização do exame e os motivos informados para não ter realizado, além de comparar o tempo do recebimento do resultado do exame no SUS e na rede privada. MÉTODOS: A partir de dados da Pesquisa Nacional de Saúde (PNS) foram calculadas as prevalências e os respectivos intervalos de confiança de realização do exame preventivo do câncer do colo do útero há menos de três anos, em mulheres de 25 a 64 anos, em 2013 e 2019. Modelos de regressão de Poisson foram utilizados para comparar as prevalências do desfecho segundo características sociodemográficas. Também foram analisados os motivos para não ter feito o exame e o tempo entre a realização e o recebimento do laudo. RESULTADOS: Houve aumento na cobertura do exame preventivo no Brasil entre 2013 (78,7%) e 2019 (81,3%) e redução na proporção de mulheres que nunca fizeram o exame de 9,7% para 6,1%. A prevalência de realização do exame foi maior em mulheres brancas, melhor escolaridade e renda mais alta, residentes nas regiões Sul e Sudeste. Os motivos mais frequentes para não realizar o exame foram achar desnecessário (45% em 2013 e em 2019) e nunca ter sido orientada a fazê-lo (20,6% em 2013 e 14,8% em 2019). CONCLUSÕES: Apesar das elevadas coberturas de rastreamento alcançadas pelo país, há grande desigualdade no acesso ao exame, e uma parcela não desprezível de mulheres está sob maior risco de morrer por uma doença que pode ser evitada. Esforços devem ser feitos para a estruturação de um programa de rastreamento organizado que identifique e capte as mulheres mais vulneráveis.OBJECTIVES: To compare the coverage of cervical cancer screening in Brazil in 2013 and 2019, investigating the factors associated with having the test performed and the reasons given for not doing it. Additionally, a comparison is made concerning the time taken to receive the test result in SUS (Sistema Único de Saúde) and in the private health services. METHODS: Using data from the National Health Survey (Pesquisa Nacional de Saúde - PNS), prevalence rates and corresponding confidence intervals were calculated to determine the frequency of recent cervical cancer screenings among women aged between 25 and 64 years old in Brazil, for both 2013 and 2019. Poisson regression models were employed to compare the prevalence of the outcome according to sociodemographic characteristics. The reasons for not having the test and the time between performing and receiving the result were also analyzed. RESULTS: The findings revealed an increase in the coverage of preventive cervical cancer exams in Brazil from 78.7% in 2013 to 81.3% in 2019. Additionally, there was a decline in the proportion of women who had never undergone the exam, from 9.7% to 6.1%. Prevalence of test uptake was higher among white women, those with higher levels of education and income, and those residing in the South and Southeast regions of the country. The most commonly cited reasons for not taking the test were the impression it was unnecessary (45% in both 2013 and 2019) and never having been asked to undergo the test (20.6% in 2013 and 14.8% in 2019). CONCLUSIONS: Despite the high coverage of screening achieved in the country, there is great inequality in access to the test, and a non-negligible number of women are at greater risk of dying from a preventable disease. Efforts must be made to structure an organized screening program that identifies and captures the most vulnerable women

Assessing Long-Term Trends In Vegetation Productivity Change Over the Bani River Basin in Mali (West Africa)

Using time series of Normalized Difference Vegetation Index (NDVI) and rainfall data, we investigated historical vegetation productivity trends from 1982 to 2011 over the Bani River Basin in Mali. Statistical agreements between long-term trends in vegetation productivty, corresponding rainfall and rate of land cover change from Landsat time-series imagery was used to discern climate versus human-induced vegetation cover change. Spearman correlation was used to investigate the relationship between metrics of vegetation, rainfall trends and land cover change categories. The results show there is a positive correlation between increases in rainfall and some land cover classes, while some classes such as settlements were negatively correlated with vegetation productivity trends. Croplands and Natural Vegetation were positively correlated (r=0.89) with rainfall while settlements have a negative correlation with NDVI time series trend (r=-057). Despite the fact that rainfall is the major determinant of vegetation cover dynamics in the study area, it appears that other human-induced factors such as urbanization have negatively influenced the change in vegetation cover in the study area. The results show that a combined analysis of NDVI, rainfall and spatially explicit land cover change provides a comprehensive insight into the drivers of vegetation cover change in semi-arid Africa

Assessing the inter-relationship between vegetation productivity, rainfall, population and land cover over the Bani River Basin in Mali (West Africa)

This research investigated the inter-relationship between vegetation productivity, measured using the Normalized Difference Vegetation Index (NDVI), change in rainfall and population density in the context of perceived greening and degradation trends over the Bani River Basin (BRB). A 30-year (1982-2011), 8-km gridded rainfall data sets was produced by inverse distance weighted (IDW) interpolation of monthly data from 40 meteorological stations contained within the basin. Population data were retrieved from the National Population Statistic data base for 1987, 1997, and 2009. Rainfall and NDVI time-series trends were computed for the 30-year period and analysed. The relationship between rainfall and NDVI at pixel level, and NDVI and population densities was analysed using a Pearson correlation. Land Use and Land Cover (LULC) conversion rates were computed for the same period using multi-temporal 30-meter Landsat imagery; ground surveys for selected areas within the basin were used for further cross-verification. The computed NDVI trends revealed that, vegetation 'greening' trends are mostly associated with areas where natural vegetation is still well represented. Concurrent with increases in rainfall over the period analysed, this finding supports the hypothesis that re-greening observed in that area is the result of multi-decadal fluctuations in climate, rather than improved land management

Remote sensing of vegetation fires and its contribution to a fire management information system

In the last decade, research has proven that remote sensing can provide very useful support to fire managers. This chapter provides an overview of the type of information remote sensing can provide to the fire community. It considers first fire management information needs in the context of fire management information system. An introduction to remote sensing then precedes the description of fire information obtainable from remote sensing data (such as vegetation status, active fire detection and burned areas assessment). Finally, operational examples in five African countries illustrate how the information can be used in practice

fMRI evidence of ‘mirror’ responses to geometric shapes

Mirror neurons may be a genetic adaptation for social interaction [1]. Alternatively, the associative hypothesis [2], [3] proposes that the development of mirror neurons is driven by sensorimotor learning, and that, given suitable experience, mirror neurons will respond to any stimulus. This hypothesis was tested using fMRI adaptation to index populations of cells with mirror properties. After sensorimotor training, where geometric shapes were paired with hand actions, BOLD response was measured while human participants experienced runs of events in which shape observation alternated with action execution or observation. Adaptation from shapes to action execution, and critically, observation, occurred in ventral premotor cortex (PMv) and inferior parietal lobule (IPL). Adaptation from shapes to execution indicates that neuronal populations responding to the shapes had motor properties, while adaptation to observation demonstrates that these populations had mirror properties. These results indicate that sensorimotor training induced populations of cells with mirror properties in PMv and IPL to respond to the observation of arbitrary shapes. They suggest that the mirror system has not been shaped by evolution to respond in a mirror fashion to biological actions; instead, its development is mediated by stimulus-general processes of learning within a system adapted for visuomotor control

8. Remote Sensing Of Vegetation Fires And Its Contribution To A Fire Management Information System

In the last decade, research has proven that remote sensing can provide very useful support to fire managers. This chapter provides an overview of the types of information remote sensing can provide to the fire community. First, it considers fire management information needs in the context of a fire management information system. An introduction to remote sensing then precedes a description of fire information obtainable from remote sensing data (such as vegetation status, active fire detection and burned areas assessment). Finally, operational examples in five African countries illustrate the practical use of remotely sensed fire information. As indicated in previous chapters, fire management usually comprises activities designed to control the frequency, area, intensity or impact of fire. These activities are undertaken in different institutional, economic, social, environmental and geographical contexts, as well as at different scales, from local to national. The range of fire management activities also varies considerably according to the management issues at stake, as well as the available means and capacity to act. Whatever the level, effective fire management requires reliable information upon which to base appropriate decisions and actions. Information will be required at many different stages of this fire management system. To illustrate this, we consider a typical and generic description of a fire management loop , as provided in Figure 8.1. Fire management objectives result from fire related knowledge . For example, they may relate to sound ecological reasons for prescribed burning in a particular land management context, or to frequent, uncontrolled fires threatening valuable natural or human resources. Whatever the issues, appropriate objectives require scientific knowledge (such as fire impact on ecosystems components, such as soil and vegetation), as well as up-to date monitoring information (such as vegetation status, fire locations, land use, socioeconomic context, etc.). Policies, generally at a national and governmental level, provide the official or legal long term framework (e.g. five to ten years) to undertake actions. A proper documentation of different fire issues, and their evolution, will allow their integration into appropriate policies, whether specific to fire management, or complementary to other policies in areas such as forestry, rangeland, biodiversity, land tenure, etc. Strategies are found at all levels of fire management. They provide a shorter-term framework (e.g. one to five years) to prioritise fire management activities. They involve the development of a clear set of objectives and a clear set of activities to achieve these objectives. They may also include research and training inputs required, in order to build capacity and to answer specific questions needed to improve fire management. The chosen strategy will result from a trade-off between priority fire management objectives and the available capacity to act (e.g. institutional framework, budget, staff, etc.), and will lead towards a better allocation of resources for fire management operations to achieve specific objectives. One example in achieving an objective of conserving biotic diversity may be the implementation of a patch-mosaic burning system (Brockett et al., 200 1 ) instead of a prescribed block burning system, based on an assumption that the former should better promote biodiversity in the long-term than the latter (Parr & Brockett, 1999). This strategy requires the implementation of early season fires to reduce the size of later season fires. The knowledge of population movements, new settlements or a coming El Nino season, should help focus the resources usage, as these factors might influence the proportion as well as the locations of area burned. Another strategy may be to prioritise the grading of fire lines earlier than usual based on information on high biomass accumulation. However, whatever the strategies, they need to be based on reliable information