As Lagoas de Pituaçú, Abaeté, Tororó e Paixão, no município de Salvador-BA (Brasil) apresentam em comum a inserção de um ecossistema lêntico no meio urbano de uma cidade em desenvolvimento. Esta ...pesquisa descreve o padrão de variação sazonal de parâmetros físico-químicos não conservativos e biológicos durante os anos de 2017 e 2018 em 16 pontos distribuídos espacialmente nas quatro lagoas durante o período chuvoso (compreendido entre os meses de abril a julho) e seco (de agosto a novembro). A qualidade da água foi determinada em acordo com o índice de Qualidade da Água (IQA) e aplicação do Índice de Estado Trófico (IET), além das classes de Resolução CONAMA 357/2005. Os resultados evidenciaram que as quatro lagoas monitoradas exibem alguns parâmetros fora das conformidades estabelecidas pelo CONAMA, além disso apresentam-se fortemente eutrofizadas, mas de forma contrastante, com boas classificações de qualidade considerando seu uso, com exceção da Lagoa de Pituaçú. Conclui-se que avaliações sistemáticas devem ser consideradas com maior frequência com o objetivo de colher maiores e mais precisas informações sobre as condições de qualidade destes ecossistemas, e estudar suas alterações de qualidade como reflexo do condicionante urbano sobre sua conservação.
We show that current differences in trust levels within Africa can be traced back to the transatlantic and Indian Ocean slave trades. Combining contemporary individual-level survey data with ...historical data on slave shipments by ethnic group, we find that individuals whose ancestors were heavily raided during the slave trade are less trusting today. Evidence from a variety of identification strategies suggests that the relationship is causal Examining causal mechanisms, we show that most of the impact of the slave trade is through factors that are internal to the individual, such as cultural norms, beliefs, and values.
Abstract
This research contributes to the literature on the relationship between board social ties and the complexity of institutional environments. It remains unclear what reactions a firm needs to ...take in response to the complexity of interconnected changes in multiple institutional dimensions. We seek to understand the changes of social ties on corporate boards due to the asynchronicity across dimensions of pro-market institutional changes—an overlooked type of institutional uncertainty. We address the gap in understanding firm responses to institutional environmental complexity by analyzing changing board social ties as a response to the asynchronicity of pro-market institutional changes in emerging markets. Based on a sample of 8205 firm-year observations during 2005–2016 in 15 emerging markets, we find that firms increased the presence of directors with both corporate interlocks and political ties in response to asynchronous pro-market institutional changes. This increase appeared less salient when the firm already had a greater presence of the other type of social ties on board or a higher percentage of state ownership. Finally, we find that the performance consequences of such board changes depend on the existing level of pro-market institutional developments.
In this ground breaking analysis, Terry Moe treats Hurricane Katrina as a natural experiment that offers a rare opportunity to learn about the role of power in the politics of institutional reform. ...When Katrina hit, it physically destroyed New Orleans' school buildings, but it also destroyed the vested-interest power that had protected the city's abysmal education system from major reform. With the constraints of power lifted, decision makers who had been incremental problem-solvers turned into revolutionaries, creating the most innovative school system in the entire country. The story of New Orleans' path from failure to revolution is fascinating, but, more importantly, it reveals the true role of power, whose full effects normally cannot be observed, because power has a 'second face' that is hidden and unobservable. Making use of Katrina's analytic leverage, Moe pulls back the curtain to show that this “second face” has profound consequences that stifle and undermine society's efforts to fix failing institutions.
Long-lasting activity of asteroid (248370) 2005 QN173 Ivanova, Oleksandra; Licandro, Javier; Moreno, Fernando ...
Monthly notices of the Royal Astronomical Society,
08/2023, Letnik:
525, Številka:
1
Journal Article
Recenzirano
Odprti dostop
ABSTRACT
We present the results of observations of asteroid (248370) QN173 obtained during July 2021–January 2022 with three telescopes. Our analysis revealed the presence of the dust tail for about ...half of a year. The direct images of the asteroid were obtained with broad-band filters. No emissions were revealed in the spectra, and the spectrum of the asteroid closely matched that of a C-type asteroid. Created colour and linear polarization variations along the tail were analysed. The asteroid demonstrated a redder colour compared to the Sun. Dramatic changes in dust productivity obtained in different filters were not detected. The g − r colour changes from 0.2m to 0.7m over the coma, and the linear polarization degree varies from about 1.2 per cent to 0.2 per cent and from −0.2 per cent to −1.5 per cent at the phase angle of 23.2° and 8.16°. The total dust mass ejected until the latest observation on October 10 is 4.2 × 107 kg, with a maximum rate of 2.6 kg s−1 based on the Monte Carlo modelling of the dust tail. The estimated asteroid size is 1.3 km. It is shown that large particles are concentrated around the nucleus, whereas smaller ones dominate in the tail. The evolution of (248370) QN173 orbit and the orbits of the sample of the 464 short-periodic comets were followed. Ten of them approached the asteroid’s orbit. These objects are not genetically related, despite very close distance of their orbits for a relatively long time.
Building and Measuring Community Resilience National Academies of Sciences, Engineering, and Medicine; Policy and Global Affairs; Office of Special Projects ...
04/2019
eBook
Odprti dostop
The frequency and severity of disasters over the last few decades have presented unprecedented challenges for communities across the United States. In 2005, Hurricane Katrina exposed the complexity ...and breadth of a deadly combination of existing community stressors, aging infrastructure, and a powerful natural hazard. In many ways, the devastation of Hurricane Katrina was a turning point for understanding and managing disasters, as well as related plan making and policy formulation. It brought the phrase "community resilience" into the lexicon of disaster management.
Building and Measuring Community Resilience: Actions for Communities and the Gulf Research Program summarizes the existing portfolio of relevant or related resilience measurement efforts and notes gaps and challenges associated with them. It describes how some communities build and measure resilience and offers four key actions that communities could take to build and measure their resilience in order to address gaps identified in current community resilience measurement efforts. This report also provides recommendations to the Gulf Research Program to build and measure resilience in the Gulf of Mexico region.
Rebuilding in Louisiana and Mississippi after Hurricanes Katrina and Rita presented some very thorny issues. Certain cultural projects benefited from immediate attention and funding while others, ...with equal cases for assistance but with less attraction to future tourist dollars, languished. New Orleans and its surroundings contain a diverse mixture of Native Americans, African Americans, Creoles, Cajuns, Isleños with roots in the Canary Islands, and the descendants of Italian, Irish, English, Croatian, and German immigrants, among others. Since 2005 much is now different for the people of the Gulf Coast, and much more stands to change as governments, national and international nonprofit organizations, churches, and community groups determine how and even where life will continue. This collection elucidates how this process occurs and seeks to understand the cultures that may be saved through assistance or may be allowed to fade away through neglect. Essays in Culture after the Hurricanes examine the ways in which a wide variety of stakeholders---community activists, elected officials, artists, and policy administrators---describe, quantify, and understand the unique assets of the region. Contributors question the process of cultural planning by analyzing the language employed in decision making. They attempt to navigate between rhetoric and the actual experience of ordinary citizens, examining the long-term implications for those who call the Gulf Coast home.
OBJECTIVE:To update the 2005 American Academy of Neurology (AAN) guideline on corticosteroid treatment of Duchenne muscular dystrophy (DMD).
METHODS:We systematically reviewed the literature from ...January 2004 to July 2014 using the AAN classification scheme for therapeutic articles and predicated recommendations on the strength of the evidence.
RESULTS:Thirty-four studies met inclusion criteria.
RECOMMENDATIONS:In children with DMD, prednisone should be offered for improving strength (Level B) and pulmonary function (Level B). Prednisone may be offered for improving timed motor function (Level C), reducing the need for scoliosis surgery (Level C), and delaying cardiomyopathy onset by 18 years of age (Level C). Deflazacort may be offered for improving strength and timed motor function and delaying age at loss of ambulation by 1.4–2.5 years (Level C). Deflazacort may be offered for improving pulmonary function, reducing the need for scoliosis surgery, delaying cardiomyopathy onset, and increasing survival at 5–15 years of follow-up (Level C for each). Deflazacort and prednisone may be equivalent in improving motor function (Level C). Prednisone may be associated with greater weight gain in the first years of treatment than deflazacort (Level C). Deflazacort may be associated with a greater risk of cataracts than prednisone (Level C). The preferred dosing regimen of prednisone is 0.75 mg/kg/d (Level B). Over 12 months, prednisone 10 mg/kg/weekend is equally effective (Level B), with no long-term data available. Prednisone 0.75 mg/kg/d is associated with significant risk of weight gain, hirsutism, and cushingoid appearance (Level B).
Surface chemistry of mineral phases in aqueous environments generates the electrostatic forces involved in particle-particle interactions. However, few models directly take into account the influence ...of surface speciation and changes in solution speciation when the diffuse layer potential profiles of approaching particles overlap and affect each other. These electrostatic interactions can be quantified, ideally, through charge regulation, considering solution and surface speciation changes upon particle approach by coupling state-of-the-art surface complexation models for the two particle surfaces with a Poisson-Boltzmann type distribution of electrostatic potential and ions in the inter-particle space. These models greatly improve the accuracy of inter-particle force calculations at small inter-particle separations compared to constant charge and constant potential approaches. This work aims at advancing charge regulation calculations by including full chemical speciation and advanced surface complexation models (Basic Stern-, three-, or four plane models and charge distribution concepts), for cases of similar and dissimilar surfaces involving the numerical solution of the Poisson-Boltzmann equation for arbitrary electrolytes. The concept was implemented as a Python-based code and in COMSOL. The flexibility and precision of both, concept and implementations are demonstrated in several benchmark calculations testing the new codes against published results or simulations using established speciation codes, including aqueous speciation, surface complexation and various interaction force examples. Due to the flexibility in terms of aqueous chemistry and surface complexation models for various geometries, a large variety of potential applications can be tackled with the developed codes including industrial, biological, and environmental systems, from colloidal suspensions to gas bubbles, emulsions, slurries like cement paste, as well as new possibilities to assess the chemistry in nano-confined systems.
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•Surface electrostatic interactions are considered via charge regulation (CR)•CR allows precise assessment of inter particle forces on the nanoscale•CR allows precise assessment of surface and aqueous speciation in nanopores•A multipurpose CR code (SINFONIA) is implemented and benchmarked•The python implementation of SINFONIA is for free and open source available
This paper investigates whether there is a link between cognitive ability, risk aversion, and impatience, using a representative sample of roughly 1,000 German adults. Subjects participate in choice ...experiments with monetary incentives measuring risk aversion, and impatience over an annual horizon, and conduct two different, widely used, tests of cognitive ability. We find that lower cognitive ability is associated with greater risk aversion, and more pronounced impatience. These relationships are significant, and robust to controlling for personal characteristics, education, income, and measures of credit constraints. We perform a series of additional robustness checks, which help rule out other possible confounds. PUBLICATION ABSTRACT
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