Exploiting thermally-reversible chemistry for controlling the crosslinking of polymer networks

High explosives are highly sensitive to accidental detonation by impact, fire, shrapnel and small arms fire. This sensitivity can be reduced by storing the energetic material within a rubbery polymer matrix and are known as plastic bonded explosives (PBX). The current procedure used to manufacture PBX involves mixing the energetic material with a hydroxy-functionalised aliphatic polymer. Upon the addition of an isocyanate crosslinker an immediate polymerisation occurs and thus the rapidly curing mixture must be used to fill the missile or shells, referred to as ‘stores’. This process can lead to poor distribution of the crosslinker resulting in the formation of an inhomogeneously crosslinked matrix and the formation of voids. One solution to this problem involves containing the crosslinker within polyurethane microcapsules that are uniformly dispersed in the explosive-polymer mixture. Upon the application of a stimulus the crosslinker can be released from the microcapsules and the formation of a uniformly crosslinked PBX achieved. Herein is reported the design and synthesis of polyurethane microcapsules that release isocyanate crosslinkers when desired using a thermal stimulus. This has been achieved by exploiting the thermally-reversible nature of oxime-urethane and Diels-Alder adducts that have been incorporated into the shell wall of the microcapsules. An alternative approach to controlling the polymerisation of PBX materials has also been achieved using thermally-reversible blocked isocyanates that regenerate the isocyanate crosslinker when exposed to heat.

Reproductive ecology of dipsadine snakes, with emphasis on South American species

A relatively large amount of variation occurs in the reproductive ecology of tropical snakes, and this variation is generally regarded as being a consequence of seasonality in climate and prey availability. In some groups, even closely related species may differ in their reproductive ecology; however, in others it seems to be very conservative. Here we explore whether characters related to reproduction are phylogenetically constrained in a monophyletic group of snakes, the subfamily Dipsadinae, which ranges from Mexico to southern South America. We provide original data on reproduction for Leptodeira annulata, Imantodes cenchoa, and three species of Sibynomorphus from southern, southeastern and central Brazil, and data from literature for other species and populations of dipsadines. Follicular cycles were seasonal in Atractus reticulatus, Dipsa, albifrons, Hypsiglena torquata, Leptodeira maculata, L. punctata, Sibynomorphus spp. and Sibon sanniola from areas where climate is seasonal. In contrast, extended or continuous follicular cycles were recorded in Dipsas catesbyi, D. neivai, Imantodes cenchoa, Leptodeira annulata, and Ninia maculata from areas with seasonal and aseasonal climates. Testicular cycles also varied from seasonal (in H. torquiata) to continuous (in Dipsa,5 spp., Leptodeira annulata, L. maculata, N. maculata, and Sibynomorphus spp.). Most dipsadines are small (less than 500 rum SVL), and females attain sexual maturity with similar relative body size than males. Sexual dimorphism occurred in terms of SVL and tail length in most species, and clutch size tended to be small (less than five eggs). Combat behavior occurs in Imantodes cenchoa, which did not show sexual size dimorphism. Reproductive timing, for both females and males, varied among species but in general there were no differences between the tribes of Dipsadinae in most of the reproductive characteristics, such as mean body size, relative size at sexual maturity, sexual size and tail dimorphism, duration of vitellogenesis or egg-carrying in oviducts.

Invasive plants: representativeness of research from tropical countries in the global context

Biological invasions threaten the native biota of several countries and this threat is even greater in the tropical regions that have the greatest biodiversity. In order to evaluate the representativeness of studies on invasive plants in tropical countries compared to the world, as well as the region of origin and habits of the most reported invasive plants in research, we analyzed the publications from eight of the most important international journals that address the theme, from January 1995 to December 2004. The articles on biological invasions were classified as theoretical or as case studies, and according to their approach, main question, where the study was conducted, region of origin and habit of the invasive plant. Case studies predominated, as did questions about the environment`s susceptibility to the invasion, the species` invasive power and the impacts it had. The most reported invasive species were herbaceous plants from Asia and Europe. Few articles address tropical environments and only one referred to Brazil. Most referred to North America and Europe. This small number of publications in the tropics indicates the need for a global projection on this subject and underscores the lack of consistent and organized data to understand the phenomenon and propose effective strategies to combat biological invasion.

A modified rat model of neonatal anoxia: Development and evaluation by pulseoximetry, arterial gasometry and Fos immunoreactivity

Neonatal anoxia is a worldwide clinical problem that has serious and lasting consequences. The diversity of models does not allow complete reproducibility, so a standardized model is needed. In this study, we developed a rat model of neonatal anoxia that utilizes a semi-hermetic system suitable for oxygen deprivation. The validity of this model was confirmed using pulse oximetry, arterial gasometry, observation of skin color and behavior and analysis of Fos immunoreactivity in brain regions that function in respiratory control. For these experiments, 87 male albino neonate rats (Rattus norvegicus, lineage Wistar) aged approximate 30 postnatal hours were divided into anoxia and control groups. The pups were kept in an euthanasia polycarbonate chamber at 36 +/- 1 degrees C, with continuous 100% nitrogen gas flow at 3 L/min and 101.7 kPa for 25 min. The peripheral arterial oxygen saturation of the anoxia group decreased 75% from its initial value. Decreased pH and partial pressure of oxygen and increased partial pressure of carbon dioxide were observed in this group, indicating metabolic acidosis, hypoxia and hypercapnia. respectively. Analysis of neuronal activation showed Fos immunoreactivity in the solitary tract nucleus, the lateral reticular nucleus and the area postrema, confirming that those conditions activated areas related to respiratory control in the nervous system. Therefore, the proposed model of neonatal anoxia allows standardization and precise control of the anoxic condition, which should be of great value in indentifying both the mechanisms underlying neonatal anoxia and novel therapeutic strategies to combat or prevent this widespread public health problem. (C) 2011 Elsevier B.V. All rights reserved.

Systematic structural studies of iron superoxide dismutases from human parasites and a statistical coupling analysis of metal binding specificity

Superoxide dismutases (SODs) are a crucial class of enzymes in the combat against intracellular free radical damage. They eliminate superoxide radicals by converting them into hydrogen peroxide and oxygen. In spite of their very different life cycles and infection strategies, the human parasites Plasmodium falciparum, Trypanosoma cruzi and Trypanosoma brucei are known to be sensitive to oxidative stress. Thus the parasite Fe-SODs have become attractive targets for novel drug development. Here we report the crystal structures of FeSODs from the trypanosomes T. brucei at 2.0 angstrom and T. cruzi at 1.9 angstrom resolution, and that from P. falciparum at a higher resolution (2.0 angstrom) to that previously reported. The homodimeric enzymes are compared to the related human MnSOD with particular attention to structural aspects which are relevant for drug design. Although the structures possess a very similar overall fold, differences between the enzymes at the entrance to the channel which leads to the active site could be identified. These lead to a slightly broader and more positively charged cavity in the parasite enzymes. Furthermore, a statistical coupling analysis (SCA) for the whole Fe/MnSOD family reveals different patterns of residue coupling for Mn and Fe SODs, as well as for the dimeric and tetrameric states. In both cases, the statistically coupled residues lie adjacent to the conserved core surrounding the metal center and may be expected to be responsible for its fine tuning, leading to metal ion specificity.

MODELLING AND FORECASTING INFLATION RATES IN GHANA: AN APPLICATION OF SARIMA MODELS

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.

Gender Equality a case study of Sweden : Gender Equality Gender Equity and policies of combating inequality at workplace to make the society equal.

The paper analyses Gender Equality, Gender Equity and policies of combating inequality at workplace to make the society equal as a case study of Sweden. The aim of paper is see the gender equality, gender equity, discrimination against women at workplace and to describe the policies combating inequality in the welfare state of Sweden. This work highlights the gender equality in terms of institutionalizing gender equality, gender equity, gender and pay gap, parental leave, gender and the pension system and sexual behavior directed towards women and policies combating inequality to bring equality in society. For my research I used the secondary data the fact sheets, scientific literature, statistics from eurostate of Sweden and case studies about Swedish society and the theoretical explanation to explain the phenomena. To achieve my aim I used the combination of both qualitative and quantitative methods of research. I showed the empirical evidences of these phenomena from the Swedish society and theoretical analysis about equality and equity of gender in different wakes of life. I found an interesting conclusion that there are good policies and legislation to combat inequality to bring society but there are no policies to change the perception of society about male and female role.

Le Réalisme dans le roman policier : Une Analyse du réalisme des décors, des personnages et de l'enquête dans deux romans policiers

Ce mémoire a pour but de comparer deux romans policiers contemporains et ayant eu un grand succès, l’un écrit par Henning Mankell dont la traduction française a paru sous le titre Les Morts de la Saint-Jean et le second est Pars vite et reviens tard de Fred Vargas. L’objectif de la candidate est d’essayer de trouver les éléments réalistes dans le décor, les personnages et l’enquête. Pour ce qui est du premier paramètre, la candidate montre que Mankell n’essaie jamais de cacher la vérité derrière une surface idéale ; il en va de même pour Vargas qui accentue les points de vue divergents des Français sur la réalité de leur pays. En ce qui a trait aux personnages, on distingue dans le portrait qu’en fait Mankell un combat compliqué et non manichéen, proche de la réalité psychologique; idem pour ceux de Vargas, mais le réalisme est quelque peu atténué par un recours au mystère. Enfin, l’enquête menée par Wallander aboutit un peu par hasard grâce à son intuition alors qu’Adamsberg résout l’énigme grâce à sa faculté de voir, de s’imaginer et d’aller au-delà de la capacité des autres. La conclusion générale du mémoire est que ces deux œuvres sont tout à fait réalistes, mais à un degré un peu différent. Le roman de Mankell l’est sans doute davantage dans la mesure où le recours au mystère est écarté et que l’enquête est menée de façon logique alors que le roman de Vargas, tout en suivant les règles de la logique, a tendance à faire appel au merveilleux. En tout état de cause, il s’agit de deux œuvres réalistes comportant un côté romantique plus ou moins bien exprimé.

Skolkuratorns roll i arbetet mot mobbning : En kvalitativ studie

Syftet med studien var att undersöka hur skolkuratorerna upplever sitt arbete mot mobbning och hur de praktiskt arbetar mot mobbning. Metoden var kvalitativ och intervjuer genomfördes med sju skolkuratorer på olika skolor i två mindre kommuner. Studien visade att skolkuratorerna vill arbeta mer med det förebyggande arbetet mot mobbningen än det finns tid till. Deras arbete handlar mycket om att gå in och hjälpa där behovet och mobbningsproblematiken redan finns. I de metoder och program som finns att tillgå i arbetet mot mobbningen är det inget som rekommenderas utan det är upp till skolkuratorerna att själva utforma en metod som ska passa den individuella eleven. Det finns ett behov av att utveckla ett program- och metodkoncept som motsvarar dagens problematik.

Soft computing in biometrics : a pragmatic appraisal

The ever increasing spurt in digital crimes such as image manipulation, image tampering, signature forgery, image forgery, illegal transaction, etc. have hard pressed the demand to combat these forms of criminal activities. In this direction, biometrics - the computer-based validation of a persons' identity is becoming more and more essential particularly for high security systems. The essence of biometrics is the measurement of person’s physiological or behavioral characteristics, it enables authentication of a person’s identity. Biometric-based authentication is also becoming increasingly important in computer-based applications because the amount of sensitive data stored in such systems is growing. The new demands of biometric systems are robustness, high recognition rates, capability to handle imprecision, uncertainties of non-statistical kind and magnanimous flexibility. It is exactly here that, the role of soft computing techniques comes to play. The main aim of this write-up is to present a pragmatic view on applications of soft computing techniques in biometrics and to analyze its impact. It is found that soft computing has already made inroads in terms of individual methods or in combination. Applications of varieties of neural networks top the list followed by fuzzy logic and evolutionary algorithms. In a nutshell, the soft computing paradigms are used for biometric tasks such as feature extraction, dimensionality reduction, pattern identification, pattern mapping and the like.

Social Media, Privacy, and the Academic Classroom

We live in a world full of social media and portable technology that allows for the effortless access to, and sharing of, information. While this constant connection can be viewed as a benefit by some, there have been recent, sometimes embarrassing, instances throughout the world that show just how quickly any expectation of privacy can be destroyed. From pictures of poorly dressed shoppers at a grocery store to customers recording interactions with their servers at restaurants, the internet is full of media (all with the potential to go viral) created and posted without consent of all parties captured. This risk to privacy is not just limited to retail and restaurants, as being in any situation amongst people puts you at risk, including being in an academic classroom. Anyone providing in-class instruction, be they professor or librarian, can be at risk for this type of violation of privacy. In addition, the students in the class are also at risk for being unwittingly captured by their classmates. To combat this, colleges and universities are providing recommendations to faculty regarding this issue, such as including suggested syllabus statements about classroom recording by students. In some instances, colleges and universities have instituted formal policies with strict penalties for violators. An overview of current privacy law as it relates to an academic setting is discussed as well as recent, newsworthy instances of student recording in the classroom and the resulting controversies. Additionally, there is a discussion highlighting various recommendations and formal policies that have been issued and adopted by colleges and universities around the country. Finally, advice is offered about what librarians can do to educate students, faculty, and staff about the privacy rights of others and the potential harm that could come from posting to social media and the open web images and video of others without their consent.

Creating High-Impact Workforce Development Programs

As communities across the nation continue to face persistent unemployment, many states are turning to community college workforce development programs to combat joblessness. However, state governments and community colleges alike are often unable to devote significant resources to building new workforce initiatives. This brief examines how community colleges in four states have worked with state governments and other partners to overcome budget constraints and create effective workforce development programs, highlighting funding models and innovative practices to make efficient use of limited resources.

Terrorismo: aspectos gerais, prevenção e repressão

Este resumo tem como objetivo estudar o terrorismo e como combatê-lo no Brasil, bem como analisar o que a legislação brasileira e internacional tratam o tema. O terrorismo é um mal atual em todo o mundo e o Brasil não está isento de ataques terroristas, sendo de extrema importância o estudo, uma vez que a legislação atual não tem o tipo penal, nem medidas espec~ificas para prevenção e repressão no âmbito legislativo.

Uma nova versão para a política monetária do Plano de Ação Econômica do Governo (Paeg)

Existem divergências entre Lara Resende (1982) e Cysne (1993) sobre o que determinou o descumprimento das metas monetárias que serviram como um dos instrumentos de combate a inflação no PAEG. Para se entender o que de fato ocorreu, reconstruímos a oferta de moeda a partir das variáveis descritas por estes autores como relevantes na sua argumentação. Pelo descrito, tudo indicava uma mudança estrutural, mas, usando a técnica de Chow, ficou evidente que a mesma ocorreu com o advento do Plano Trienal, não com o PAEG. Para percebermos isto, trabalhamos com um período superior a implantação e execução do PAEG (1960:01 a 1968:12). Esta investigação demonstrou duas coisas: erros na utilização analítica (este é o caso do papel das reservas internacionais e mudança estrutural) e peso de argumentação desmedida (este é o caso do papel dado ao crédito concedido pela Autoridade Monetária via Banco do Brasil ao setor privado). Afora isto, o que se tem de concreto, é que a oferta de moeda não foi resultado de uma variável isolada, mas de um conjunto bem articulado que, apesar das suas diferenças de influência, produziram no período específico em que se tem o PAEG (não pelo PAEG), uma oferta de moeda cadente e fora das metas monetárias previstas.

Financial regulation and international criminal policy: the anti-money laundering system in Brazil and Argentina

The objective of this paper is to present and compare the process and the results of the implementation of the anti-money laundering system in Brazil and Argentina. Considering that the internal transformations cannot be discussed without a clear understanding of the international apparatus, attention will be given to the description of the “international policy” designed and conducted by FATF. Therefore, its incorporation into two different national realities, the Brazilian and the Argentinean ones, will shed light not only on the transnational transformations both States underwent but also on the anti-money laundering regime itself. The paper is divided into five parts. The first one presents a brief introduction on the emergence and development of the relationship between financial regulation and criminal policy. The two following sections are designed to present an overview of the anti money laundering system in Brazil and Argentina and of the role of FATF in their implementation process. The fourth section presents two Brazilian examples of situations in which full advantage of the FATF regime was taken: the National Strategy to Combat Corruption and Money Laundering and the BacenJud, a communication channel between the financial system and the judicial power. To conclude, final comments will be presented in connection with the central questions of the project this paper is part of .