7,990 research outputs found
Pressure and velocity measurements in a three-dimensional wall jet
The effects on the flow fields of varying the ratio of the velocity at the exit plane of the nozzle to the outer tunnel flow are reported. The pressure-velocity correlations are taken and some trends are discussed. Emphasis is placed on comparing the coherence between the fluctuating pressure and velocity fields at various locations in the different flow configurations
An experimental investigation of an axisymmetric jet in a coflowing airstream
The flow development of an axisymmetric jet exhausting into a moving airstream has been studied. The jet has a Reynolds number of 22,600, and the ratio of the jet velocity to the wind tunnel velocity is 5.1 to 1. The flow field of the axisymmetric jet was examined at locations varying from approximately zero to eight diameters downstream of the orifice. Of primary concern at each downstream location was the mapping of the one point statistical properties of the flow, including mean velocity, turbulent intensity, and intermittency. Autocorrelations and power spectral density curves were determined for both the fluctuating velocity field and the concentration signal at various distances from the jet's center line for different downstream locations. A laser Doppler velocimeter, using a phase locked loop processor, was used to make the desired velocity field measurements which were compared with hot wire anemometer and pressure probe data
Concepts in Animal Parasitology, Chapter 14: Mesozoa (Phylum Dicyemida and Phylum Orthonecta)
Chapter 14 in Concepts in Animal Parasitology on the Mesozoa (phylum Dicyemida and phylum Orthonectida) by Sarah R. Catalano. 2024. S. L. Gardner and S. A. Gardner, editors. Zea Books, Lincoln, Nebraska, United States. doi: 10.32873/unl.dc.ciap01
Multifunctional Manganese Single Source Precursor for the Selective Deposition of MnF2 or Mn3O4
AbstractA novel Mn(II) precursor, the Mn(hfa)2âtmeda, was successfully applied to the deposition of manganese containing nanostructures in Metal Organic Chemical Vapor Deposition (MOCVD) processes at atmospheric and reduced pressure. Experimental data evidenced that different phases were obtained, selectively and reproducibly, on varying the operating pressure. Manganese difluoride (MnF2) nanorod assemblies were obtained under atmospheric pressure, while hausmannite (Mn3O4) nanostructured films were obtained under reduced pressure. X-ray diffraction patterns in grazing incidence mode and energy dispersive X-ray analyses confirmed the phase nature and composition of the manganese containing nanostructures. Field-emission scanning electron microscopy images evidenced the nanostructure morphology of both the MnF2 and Mn3O4 phases
Representations of power: A critical multimodal analysis of U.S. CEOs, the Italian Mafia and government in the media
In September 2008, the collapse of the bank Lehman Brothers led to a financial crisis and the worst recession since the Great Depression of the 1930s, threatening the entire global financial system. Some of the effects of the crisis included evictions, foreclosures and high and prolonged unemployment. Despite the fact that bankers and corporate executives are widely known to bear much of the blame for the crisis (âThe origins of the financial crisis,â 2013), very few have actually been convicted of any crime. In addition, recent investigations of the relationship between the New York Federal Reserve and banks such as Goldman Sachs have revealed that even the regulators assigned to keep banks in check have become âtoo risk averse and deferential to the banks it supervisedâ (Bernstein 2014). Yet, the public has largely âlearned to accept the implicit idea that some people have simply more rights than others. Some people go to jail, and others just donâtâ (Taibbi 2014, xix). Similarly, in Italy, there is a large public consensus that many politicians and corporate executives are allies of Mafia groups such as âNdrangheta and Cosa Nostra (who are engaging in activities such as setting up bogus firms in order to receive public subsidies, money laundering, fraudulent real estate schemes, etc.), yet few of them ever end up being prosecuted or serving jail time. In fact, while the government has created numerous task forces to combat Mafia groups, the âNdrangheta has continued to gross billions of euros and has become a global presence, active in countries such as Germany as well as in South America (Conti 2014). The present paper seeks to understand why these CEOs and Mafia organizations are not often punished for their crimes and why there is little public outcry about it. We are concerned with one element that plays a crucial role: the lack of connection between their actions and their representation in the media. The representation of social actors in public discourse has always played an important role in how the public perceives them, how they are treated by legal and government entities and what the consequences of their actions are (van Leeuwen 1996). Discourses not only represent what is happening, but also evaluate, justify, highlight or background certain aspects of it (van Leeuwen, 2008, 6). Consequently, this multimodal critical discourse analysis will attempt to reveal less-than-obvious discursive strategies that (re)produce dominant ideologies of criminality and how groups in power, convicted or accused of crimes, are treated in the discourse. To do this, we take a qualitative approach that examines online newspaper articles reporting crimes committed by CEOs in the U.S. and Italian Mafia groups. Our focus is on the metonymic strategies
Representations of power: A critical multimodal analysis of U.S. CEOs, the Italian Mafia and government in the media
In September 2008, the collapse of the bank Lehman Brothers led to a financial crisis and the worst recession since the Great Depression of the 1930s, threatening the entire global financial system. Some of the effects of the crisis included evictions, foreclosures and high and prolonged unemployment. Despite the fact that bankers and corporate executives are widely known to bear much of the blame for the crisis (âThe origins of the financial crisis,â 2013), very few have actually been convicted of any crime. In addition, recent investigations of the relationship between the New York Federal Reserve and banks such as Goldman Sachs have revealed that even the regulators assigned to keep banks in check have become âtoo risk averse and deferential to the banks it supervisedâ (Bernstein 2014). Yet, the public has largely âlearned to accept the implicit idea that some people have simply more rights than others. Some people go to jail, and others just donâtâ (Taibbi 2014, xix). Similarly, in Italy, there is a large public consensus that many politicians and corporate executives are allies of Mafia groups such as âNdrangheta and Cosa Nostra (who are engaging in activities such as setting up bogus firms in order to receive public subsidies, money laundering, fraudulent real estate schemes, etc.), yet few of them ever end up being prosecuted or serving jail time. In fact, while the government has created numerous task forces to combat Mafia groups, the âNdrangheta has continued to gross billions of euros and has become a global presence, active in countries such as Germany as well as in South America (Conti 2014). The present paper seeks to understand why these CEOs and Mafia organizations are not often punished for their crimes and why there is little public outcry about it. We are concerned with one element that plays a crucial role: the lack of connection between their actions and their representation in the media. The representation of social actors in public discourse has always played an important role in how the public perceives them, how they are treated by legal and government entities and what the consequences of their actions are (van Leeuwen 1996). Discourses not only represent what is happening, but also evaluate, justify, highlight or background certain aspects of it (van Leeuwen, 2008, 6). Consequently, this multimodal critical discourse analysis will attempt to reveal less-than-obvious discursive strategies that (re)produce dominant ideologies of criminality and how groups in power, convicted or accused of crimes, are treated in the discourse. To do this, we take a qualitative approach that examines online newspaper articles reporting crimes committed by CEOs in the U.S. and Italian Mafia groups. Our focus is on the metonymic strategies
Dancing across difference: arts and community-based interventions as intercultural education
There is an ever-present need to foster and maintain intercultural competence in todayâs teaching force. Although much research details how to do this, few studies document how to utilize arts and community-based (ACB) approaches to align with the goals of intercultural education. This qualitative study examines reflections from 61 teacher learners who participated in an ACB intervention with community partners while enrolled in an undergraduate or graduate course focused on serving students with immigrant/refugee backgrounds. The aim of this study was to find out what the characteristics of good intercultural education are, as well as how ACB approaches can provide students with authentic experiences working across difference. Using thematic analysis to examine written reflections on the interventions, the authors found that in various ways and to various degrees, the ACB approach allowed students to find a common language as they grew in their content knowledge, created a sense of vulnerability that led to increased empathy for their students and families, and compelled the students to begin to challenge oppression and work towards social change
Male fetal loss in the U.S. following the terrorist attacks of September 11, 2001
Background: The secondary sex ratio (i.e., the odds of a male birth) reportedly declines following natural disasters, pollution events, and economic collapse. It remains unclear whether this decline results from an excess of male fetal loss or reduced male conceptions. The literature also does not converge as to whether the terrorist attacks of September 11, 2001 induced "communal bereavement", or the widespread feeling of distress among persons who never met those directly involved in the attacks. We test the communal bereavement hypothesis among gravid women by examining whether male fetal deaths rose above expected levels in the US following September 11, 2001. Methods: We apply interrupted time-series methods to all fetal deaths at or greater than the 20(th) week of gestation in the US from 1996 to 2002. Time-series methods control for trends, seasonality, and other forms of autocorrelation that could induce spurious associations. Results: Results support the hypothesis in that the fetal death sex ratio (i.e., the odds of a male fetal death) increased above its expected value in September 2001. Additional analysis of the secondary sex ratio indirectly supports that the terrorist attacks may have threatened the gestation of male more than female fetuses. Conclusions: Societal responses to events such as September 11, 2001 do not appear confined only to persons who have ever met the deceased. The fetal death sex ratio in the US population may serve as a sentinel indicator of the degree to which pregnant women react to population stressors
Blurring the boundaries between synthesis and evaluation. A customized realist evaluative synthesis into adolescent risk behavior prevention
Realist methodologies have been increasingly advocated for the investigation of complex social issues. Public health programs, such as those designed to prevent adolescent risk behavior, are typically considered complex. In conducting a realist review of the empirical literature relating to such programs, we encountered several challenges, including (a) an overabundance of empirical evidence, (b) a problematic level of heterogeneity within and between methodological approaches, (c) discrepancies between theoretical underpinnings and program operationalization, (d) homogeneity of program outcomes, with very little variation in program effectiveness, and (d) a paucity of description relating to content and process. To overcome these challenges, we developed a customized approach to realist evidence synthesis, drawing on the VICTORE (Volition, Implementation, Contexts, Time, Outcomes, Rivalry, and Emergence) complexity checklist and incorporating stakeholder engagement as primary data to achieve greater depth of understanding relating to contextual and mechanistic factors, and the complex interactions between them. Here we discuss the benefits of this adapted methodology alongside an overview of the research through which the methodology was developed. A key finding from this research was that combining the complexity checklist with primary data from stakeholder engagement enabled us to systematically interrogate the data across data sources, uncovering and evidencing mechanisms which may otherwise have remained hidden, giving greater ontological depth to our research findings. This paper builds on key methodological developments in realist research, demonstrating how realist methodologies can be customized to overcome challenges in developing and refining program theory from the literature, and contributes to the broader literature of innovative approaches to realist research
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