912 resultados para Human beings.
Resumo:
A culture of childhood is a shared vision – an agreed upon vision – of the needs and rights of children, including ideas about how the people of the community can collectively nurture them and at the same time be renewed by them. In other words, it is a set of values, beliefs, and practices that people have created to guide their way of nurturing young children and their families. The vision is about investing in young children and investing in the supports and relationships that children need to learn and grow, both for the reason that children carry our future and because they carry our hopes and dreams for the future. These hopes and dreams begin with birth. Sensitive, emotionally available parents create the framework for interaction with their children by responding to the baby’s cues, engaging the baby in mutual gazes, and imitating the baby. The baby, born with a primary ability to share emotions with other human beings eagerly joins the relationship dance. The intimate family circle soon widens. Providers, teachers, and directors of early childhood programs become significant figures in children’s lives—implicit or explicit partners in a "relationship dance" (Edwards & Raikes, 2002). These close relationships are believed to be critical to healthy intellectual, emotional, social, and physical development in childhood and adolescence as well. These conclusions have been documented by diverse fields of science, ranging from cognitive science to communication studies and social and personality psychology. Close relationships contribute to security and trust, promote skill development and understanding, nurture healthy physical growth, infuse developing self-understanding and self-confidence, enable self-control and emotion regulation, and strengthen emotional connections with others that contribute to prosocial motivation (Dunn, 1993; Fogel, 1993; Thompson, 1996). Furthermore, many studies showing how relationship dysfunction is linked to child abuse and neglect, aggression, criminality, and other problems involving the lack of significant human connections (Shankoff & Meisels, 2000). In extending the dance of primary relationships to new relationships, a childcare teacher can play a primary role. The teacher makes the space ready--creating a beautiful place that causes everyone to feel like dancing. Gradually, as the dance between them becomes smooth and familiar, the teacher encourages the baby to try out more complex steps and learn how to dance to new compositions, beats, and tempos. As the baby alternates dancing sometimes with one or two partners, sometimes with many, the dance itself becomes a story about who the child has been and who the child is becoming, a reciprocal self created through close relationships.
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Na sociedade contemporânea o ser humano se vê inserido – ou invadido – em ambientes cada vez mais configurados por complexos recursos tecnológicos. É o ciberespaço, onde as imagens inundam o cotidiano e se traduzem em valor, o corpo adquire novo status imaterial e as noções de lugar e tempo se transformam e quase se anulam. O cinema pensa e produz também uma desterritorialização da imagem em movimento desde os seus primeiros tempos de imagem-máquina. Este trabalho reflete sobre as transformações da ordem social que implicam a emergência de uma “iconomia” a partir dos espaços simbólicos, tomando três momentos críticos na história do cinema como índices de uma convergência entre material e imaterial que se consolida a partir da emergência do ciberespaço. O quase-método metapórico é mobilizado como ferramenta de reconstrução metodológica desses ícones da história do cinema relacionados à desconstrução do Homo faber. O “outro lado” do ciberespaço, abrindo continuamente novos espaços-tempos de criação de valor, identifica-se a uma iconomia em que as projeções narrativas tornam-se fontes paradigmáticas de valor e de “mais gozar”.
Resumo:
Erysipelothrix rhusiopathiae causes a variety of diseases in many animal species, including human beings. Most human infections caused by this pathogen are related to occupational exposure, and swine are considered to be the most important reservoir of E. rhusiopathiae. The white-lipped peccary (Tayassu pecari) is an ungulate that has some genetic relationship to swine, and since the demand for T. pecari meat has recently increased in Brazil and nothing is known about the relationship of this peccary with the occupational zoonotic agent, E. rhusiopathiae, an investigation on the matter was conducted. Tonsils from 21 T. pecari slaughtered in southern Brazil were examined, and one animal was positive for E. rhusiopathiae isolation. Five colonies of this positive specimen had their species identity confirmed by PCR, and were characterized by serotyping, broth microdilution susceptibility test, and pulsed field gel electrophoresis (PFGE). All colonies belonged to serotype 2b, and presented identical susceptibility profiles. Nevertheless, the five colonies showed three different PFGE profiles, demonstrating the occurrence of infection by different E. rhusiopathiae genotypes. This is the first report of E. rhusiopathiae infection in T. pecari as well as the first description of animals carrying different E. rhusiopathiae genotypes.
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During 2008D2010, ticks were collected from road-killed wild animals within the Serra dos Orgaos National Park area in the state of Rio de Janeiro, Brazil. In total, 193 tick specimens were collected, including Amblyomma dubitatum Neumann and Amblyomma cajennense (F.) from four Hydrochoerus hydrochaeris (L.), Amblyomma calcaratum Neumann and A. cajennense from four Tamandua tetradactyla (L.), Amblyomma aureolatum (Pallas) and A. cajennense from five Cerdocyon thous L., Amblyomma longirostre (Koch) from one Sphiggurus villosus (Cuvier), Amblyomma varium Koch from three Bradypus variegatus Schinz, and A. cajennense from one Buteogallus meridionalis (Latham). Molecular analyses based on polymerase chain reaction targeting two rickettsial genes (gltA and ompA) on tick DNA extracts showed that 70.6% (12/17) of the A. dubitatum adult ticks, and all Amblyomma sp. nymphal pools collected from capybaras were shown to contain rickettsial DNA, which after DNA sequencing, revealed to be 100% identical to the recently identified Rickettsia sp. strain Pampulha from A. dubitatum ticks collected in the state of Minas Gerais, Brazil. Phylogenetic analysis with concatenated sequences (gltA-ompA) showed that our sequence from A. dubitatum ticks, referred to Rickettsia sp. strain Serra dos Orgaos, segregated under 99% bootstrap support in a same cluster with Old World rickettsiae, namely R. tamurae, R. monacensis, and Rickettsia sp. strain 774e. Because A. dubitatum is known to bite humans, the potential role of Rickettsia sp. strain Serra dos Orgaos as human pathogen must be taken into account, because both R. tamurae and R. monacencis have been reported infecting human beings.
Resumo:
In 1970, searching for the interspecies transmission of influenza viruses led to the first study on influenza viruses in domestic animals. Birds and mammals, including human beings, are their natural hosts; however, other animals may also play a role in the virus epidemiology. The objective was to investigate the incidence of influenza viruses in adult dogs raised in rural (9, 19.56%) and urban (37, 80.43%) areas in the state of Sao Paulo, Brazil. Dog serum samples were examined for antibodies to influenza viruses by the hemagglutination inhibition (HI) test using the corresponding antigens from the circulating viruses in Brazil. Dogs from rural areas presented antibodies to influenza A H3N2, and influenza A H7N7 and H3N8. In rural areas, dog sera displayed mean titers as 94.37, 227.88, 168.14, 189.62 HIU/25 mu L for subtypes H1N1, H3N2, H7N7, H3N8, respectively. About 84% and 92% of dogs from urban areas exhibited antibodies to human influenza A H1N1 and H3N2, respectively, with statistical difference at p < 0.05 between the mean titers of antibodies to H1N1 and H3N2. About 92% and 100% were positive for H7N7 and H3N8, respectively. In dogs from urban areas, the mean titers of antibodies against influenza A H1N1, H3N2, H7N7 and H3N8, were 213.96, 179.42, 231.76, 231.35 HIU/25 mu L respectively. The difference among them was not statistically significant at p > 0.05. In conclusion, these dogs were positive for both human and equine influenza viruses. The present study suggests the first evidence that influenza viruses circulate among dogs in Brazil.
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Shared attention is a type of communication very important among human beings. It is sometimes reserved for the more complex form of communication being constituted by a sequence of four steps: mutual gaze, gaze following, imperative pointing and declarative pointing. Some approaches have been proposed in Human-Robot Interaction area to solve part of shared attention process, that is, the most of works proposed try to solve the first two steps. Models based on temporal difference, neural networks, probabilistic and reinforcement learning are methods used in several works. In this article, we are presenting a robotic architecture that provides a robot or agent, the capacity of learning mutual gaze, gaze following and declarative pointing using a robotic head interacting with a caregiver. Three learning methods have been incorporated to this architecture and a comparison of their performance has been done to find the most adequate to be used in real experiment. The learning capabilities of this architecture have been analyzed by observing the robot interacting with the human in a controlled environment. The experimental results show that the robotic head is able to produce appropriate behavior and to learn from sociable interaction.
Resumo:
Os indicadores sociais se tornaram imprescindíveis no elenco de variáveis dos estudos epidemiológicos a partir da constatação de que a determinação dos agravos à saúde é complexa e multidimensional. Nessa perspectiva, a desigualdade social vem ocupando destaque como um fator explicativo das condições de saúde das populações. O objetivo é discutir as diferentes concepções que norteiam a seleção dos indicadores utilizados nos estudos epidemiológicos e abordar os efeitos psicossociais nos seres humanos acarretados pela desigualdade social. Foi realizada uma revisão da literatura acerca dos estudos epidemiológicos que utilizaram os indicadores de desigualdade social e capital social para uma melhor compreensão dos problemas de saúde, bem como uma investigação no campo da sociologia e da psicologia social. De acordo com a pesquisa pode-se constatar que há controvérsias sobre o efeito da desigualdade social na saúde humana pelo fato desses indicadores serem baseados, majoritariamente, pela renda e capacidade de consumo dos indivíduos. Da mesma forma, os indicadores de capital social em nível cognitivo e estrutural são muito limitados para compreender o dinamismo das relações sociais. Nesse sentido, são necessários mais estudos para a construção de indicadores sociais que contemplem a complexidade das sociedades modernas.
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Although the theory of evolution is more than 150 years old, a substantial proportion of the world population does not mention it when explaining the origin of human beings. The usual alternative conception is offered by creationism, one of the main obstacles to full acceptance of evolution in many countries. National polls have demonstrated that schooling and religiosity are negatively correlated, with scientists being one of the least religious professionals. Herein we analyzed both (1) the profile of 1st semester undergraduate students and (2), thesis and dissertations, concerning religious and evolutionary thoughts from Biology and Veterinary Schools at the largest university of South America. We have shown that students of Biology are biased towards evolution before they enter university and also that the presence of an evolutionary-thinking academic atmosphere influences the deism/religiosity beliefs of postgraduate students.
Resumo:
A presente pesquisa verificou se a legislação surgida após a Segunda Guerra Mundial foi apta a inibir o comportamento maleficente de médicos no auxílio em especializar, dissimular e acobertar a tortura. Foi demonstrado o envolvimento médico com experimentos em seres humanos durante a Segunda Guerra Mundial e corroborou-se que a maleficência médica ainda é usada nos dias de hoje na sociedade contemporânea, permitindo aos profissionais de saúde, desde o período da Guerra Fria, o envolvimento com a tortura e a consequente violação dos princípios da Bioética, especialmente, na conjuntura atualíssima da guerra norte-americana contra o terrorismo. Ao final foram propostas soluções, tendo em vista as noções de Bioética, as normas de Direito Internacional e os Direitos Humanos
Resumo:
O Mycobacterium bovis incluído no complexo Mycobacterium tuberculosis pode infectar várias espécies de animais domésticos e silvestres. Embora acometa principalmente animais da espécie bovina também pode infectar outros mamíferos e inclusive os seres humanos, nos quais determina um quadro clínico indistinguível do causado pelo M. tuberculosis. Em diversos países desenvolvidos, devido à aplicação de rigorosas medidas de controle e consequente redução da prevalência da tuberculose bovina, bem como de infecções em outras espécies de animais pelo M. bovis houve em decréscimo dos níveis de ocorrência desta patologia e o tema passou a ser considerado de menor importância. No entanto, nos países em desenvolvimento, a infecção por M. bovis ainda representa um importante risco para a saúde pública, pois tem sido observada nos animais domésticos, silvestres e em seres humanos. O presente trabalho analisa a importância da infecção pelo Mycobacterium bovis em termos de saúde pública.
Resumo:
The thesis deals with the heterogenous category of the “unaccompanied minors”, concentrating the scientific work on those who migrate from Romania to the Italian city of Bologna. Between different migratory routes that include Romanian minors, I chose to explore the ones linked with the underground and illegal contexts. In order to analyse the reasons and the morphology of their migratory career, I used the multisituated field research which allowed me to consider the social policies in both the Romanian and the Italian environment. The main debate on the situation of the “unaccompanied children” refers to the extent to which these minors leave their country of origin “accompanied” by different adult figures and it also involves the role played by these adults. The first chapter is dedicated to a brief theoretical and methodological introduction to the main arguments of the thesis such as Romanian migration to Italy, trafficking in human beings, transnationality of migrant’s migration and decentered cooperation as a means of contrasting illegal migration and trafficking. Each field of research is characterized by a specific methodological approach, but they are all linked by the anthropological perspective I adopted throughout the entire work. The Romanian context, analized from a diachronic and a synchronic perspective represents the object of the second chapter. Some aspects of the Regime policies and other characteristics of the Romanian poscomunist period of “transition” are useful frameworks that become a background of the migration flows outside the country. The third chapter focuses on the Romanian patterns of migration. The reconstruction of some past attitudes that Romanians adopted towards migration are relevant in order to reveal the continuity with the present migratory practices. A consistent part is dedicated to a concrete example based on a field research in Bologna on a group of Romanian roma migrating from the south of Romania. The contact with these persons opened a debate on the limits between legal and illegal migration practices among the Romanians. The conclusion is that minors’ migration to Italy follows the adult patterns and flows. The nucleus of the field researches is included in the fourth and the fifth chapter. Before presenting the settings and the itineraries of the field researches, some deconstructive reflections are made on the representations that common sense and social sciences create on concepts as “child”, “minor” and “childhood”. A first perspective on the Romanian migrant minors emerges from a research concentrated on a group of roma teenagers engaged in Bologna in activities like windscreen washing, pocket-picking, begging and street prostitution. The aim of the research was to gain access to their daily life, to observe their relationship with the adults who “accompany” them and the strategies they activate in order to take some material profit out of their migratory experience. A parallel field research focuses on the Romanian minors who are part of the roma group coming from the south of Romania. Most of them are reunited with their family in Bologna, but according to the Italian law, they are all living as illegal migrants. Others are only temporary sheltered by these families and they meanwhile dedicate to illegal survviving practices. An interesting point of my participant observation was to reveal the motivations that these minors give when asked about the refusal to start a legal career inside the local Centres dedicated to the “non accompanied minors”. Their autoreflexivity brings some light on the controversy regarding the adequacy of the local and national care system and the migratory projects the minors have. In this respect, a small part of the research is dedicated to the phenomena of minors’ street prostitution in Bologna, as a useful contribution to the fragmented vision researchers have on the “unaccompanied” or “separated” children. The last chapter focuses on a decentered cooperation project that emerged as an alternative response the local administration from Bologna had chosen for facing the presence of numerous migrants coming from the south of Romania. The group of Romanian roma who was also the object of my field research became the starting point for the cooperation proposals between the city of Bologna and the city of Craiova. Although there are three projects involving the two administrations, throughout a period of stage in the Romanian city of Craiova I chose to analyse, only the one dedicated to the “urgent measures” requested in order to contrast the illegal migration and the trafficking in minors. This final part of the thesis highlightens the possible contribution that such a project might bring to the study of a complex and in some parts contradictory phenomena as that of the “unaccompanied” migrant minors.
Resumo:
Interactive theorem provers (ITP for short) are tools whose final aim is to certify proofs written by human beings. To reach that objective they have to fill the gap between the high level language used by humans for communicating and reasoning about mathematics and the lower level language that a machine is able to “understand” and process. The user perceives this gap in terms of missing features or inefficiencies. The developer tries to accommodate the user requests without increasing the already high complexity of these applications. We believe that satisfactory solutions can only come from a strong synergy between users and developers. We devoted most part of our PHD designing and developing the Matita interactive theorem prover. The software was born in the computer science department of the University of Bologna as the result of composing together all the technologies developed by the HELM team (to which we belong) for the MoWGLI project. The MoWGLI project aimed at giving accessibility through the web to the libraries of formalised mathematics of various interactive theorem provers, taking Coq as the main test case. The motivations for giving life to a new ITP are: • study the architecture of these tools, with the aim of understanding the source of their complexity • exploit such a knowledge to experiment new solutions that, for backward compatibility reasons, would be hard (if not impossible) to test on a widely used system like Coq. Matita is based on the Curry-Howard isomorphism, adopting the Calculus of Inductive Constructions (CIC) as its logical foundation. Proof objects are thus, at some extent, compatible with the ones produced with the Coq ITP, that is itself able to import and process the ones generated using Matita. Although the systems have a lot in common, they share no code at all, and even most of the algorithmic solutions are different. The thesis is composed of two parts where we respectively describe our experience as a user and a developer of interactive provers. In particular, the first part is based on two different formalisation experiences: • our internship in the Mathematical Components team (INRIA), that is formalising the finite group theory required to attack the Feit Thompson Theorem. To tackle this result, giving an effective classification of finite groups of odd order, the team adopts the SSReflect Coq extension, developed by Georges Gonthier for the proof of the four colours theorem. • our collaboration at the D.A.M.A. Project, whose goal is the formalisation of abstract measure theory in Matita leading to a constructive proof of Lebesgue’s Dominated Convergence Theorem. The most notable issues we faced, analysed in this part of the thesis, are the following: the difficulties arising when using “black box” automation in large formalisations; the impossibility for a user (especially a newcomer) to master the context of a library of already formalised results; the uncomfortable big step execution of proof commands historically adopted in ITPs; the difficult encoding of mathematical structures with a notion of inheritance in a type theory without subtyping like CIC. In the second part of the manuscript many of these issues will be analysed with the looking glasses of an ITP developer, describing the solutions we adopted in the implementation of Matita to solve these problems: integrated searching facilities to assist the user in handling large libraries of formalised results; a small step execution semantic for proof commands; a flexible implementation of coercive subtyping allowing multiple inheritance with shared substructures; automatic tactics, integrated with the searching facilities, that generates proof commands (and not only proof objects, usually kept hidden to the user) one of which specifically designed to be user driven.
Resumo:
INTRODUCTION – In human medicine, diabetes mellitus (DM), hypertension, proteinuria and nephropathy are often associated although it is still not clear whether hypertension is the consequence or the cause of nephropathy and albuminuria. Microalbuminuria, in humans, is an early and sensitive marker which permits timely and effective therapy in the early phase of renal damage. Conversely, in dogs, these relationships were not fully investigated, even though hypertension has been associated with many diseases (Bodey and Michell, 1996). In a previous study, 20% of diabetic dogs were found proteinuric based on a U:P/C > 1 and 46% were hypertensive; this latter finding is similar to the prevalence of hypertension in diabetic people (40-80%) (Struble et al., 1998). In the same canine study, hypertension was also positively correlated with the duration of the disease, as is the case in human beings. Hypertension was also found to be a common complication of hypercortisolism (HC) in dogs, with a prevalence which varies from 50 (Goy-Thollot et al., 2002) to 80% (Danese and Aron, 1994).The aim of our study was to evaluate the urinary albumin to creatinine ratio (U:A/C) in dogs affected by Diabetes Mellitus and HC in order to ascertain if, as in human beings, it could represent an early and more sensitive marker of renal damage than U:P/C. Furthermore, the relationship between proteinuria and hypertension in DM and HC was also investigated. MATERIALS AND METHODS – Twenty dogs with DM, 14 with HC and 21 healthy dogs (control group) were included in the prospective case-control study. Inclusion criteria were hyperglycaemia, glicosuria and serum fructosamine above the reference range for DM dogs and a positive ACTH stimulation test and/or low-dose dexamethasone test and consistent findings of HC on abdominal ultrasonography in HC dogs. Dogs were excluded if affected by urinary tract infections and if the serum creatinine or urea values were above the reference range. At the moment of inclusion, an appropriate therapy had already been instituted less than 1 month earlier in 12 diabetic dogs. The control dogs were considered healthy based on clinical exam and clinicopathological findings. All dogs underwent urine sample collection by cystocentesis and systemic blood pressure measurement by means of either an oscillometric device (BP-88 Next, Colin Corporation, Japan) or by Doppler ultrasonic traducer (Minidop ES-100VX, Hadeco, Japan). The choice of method depended on the dog’s body weight: Doppler ultrasonography was employed in dogs < 20 kg of body weight and the oscillometric method in the other subjects. Dogs were considered hypertensive whenever systemic blood pressure was found ≥ 160 mmHg. The urine was assayed for U:P/C and U:A/C (Gentilini et al., 2005). The data between groups were compared using the Mann-Whitney U test. The reference ranges for U:P/C and U:A/C had already been established by our laboratory as 0.6 and 0.05, respectively. U:P/C and U:A/C findings were correlated to systemic blood pressure and Spearman R correlation coefficients were calculated. In all cases, p < 0.05 was considered statistically significant. RESULTS – The mean ± sd urinary albumin concentration in the three groups was 1.79 mg/dl ± 2.18; 20.02 mg/dl ± 43.25; 52.02 mg/dl ± 98.27, in healthy, diabetic and hypercortisolemic dogs, respectively. The urine albumin concentration differed significantly between healthy and diabetic dogs (p = 0.008) and between healthy and HC dogs (p = 0.011). U:A/C values ranged from 0.00 to 0.34 (mean ± sd 0.02 ± 0.07), 0.00 to 6.72 (mean ± sd 0.62 ± 1.52) and 0.00 to 5.52 (mean ± sd 1.27 ± 1.70) in the control, DM and HC groups, respectively; U:P/C values ranged from 0.1 to 0.6 (mean ± sd 0.17 ± 0.15) 0.1 to 6.6 (mean ± sd 0.93 ± 1.15) and 0.2 to 7.1 (mean ± sd 1.90 ± 2.11) in the control, DM and HC groups, respectively. In diabetic dogs, U:A/C was above the reference range in 11 out of 20 dogs (55%). Among these, 5/20 (25%) showed an increase only in the U:A/C ratio while, in 6/20 (30%), both the U:P/C and the U:A/C were abnormal. Among the latter, 4 dogs had already undergone therapy. In subjects affected with HC, U:P/C and U:A/C were both increased in 10/14 (71%) while in 2/14 (14%) only U:A/C was above the reference range. Overall, by comparing U:P/C and U:A/C in the various groups, a significant increase in protein excretion in disease-affected animals compared to healthy dogs was found. Blood pressure (BP) in diabetic subjects ranged from 88 to 203 mmHg (mean ± sd 143 ± 33 mmHg) and 7/20 (35%) dogs were found to be hypertensive. In HC dogs, BP ranged from 116 to 200 mmHg (mean ± sd 167 ± 26 mmHg) and 9/14 (64%) dogs were hypertensive. Blood pressure and proteinuria were not significantly correlated. Furthermore, in the DM group, U:P/C and U:A/C were both increased in 3 hypertensive dogs and 2 normotensive dogs while the only increase of U:A/C was observed in 2 hypertensive and 3 normotensive dogs. In the HC group, the U:P/C and the U:A/C were both increased in 6 hypertensive and 2 normotensive dogs; the U:A/C was the sole increased parameter in 1 hypertensive dog and in 1 dog with normal pressure. DISCUSSION AND CONCLUSION- The findings of this study suggest that, in dogs affected by DM and HC, an increase in U:P/C, U:A/C and systemic hypertension is frequently present. Remarkably, some dogs affected by both DM and HC showed an U:A/C but not U:P/C above the reference range. In diabetic dogs, albuminuria was observed in 25% of the subjects, suggesting the possibility that this parameter could be employed for detecting renal damage at an early phase when common semiquantiative tests and even U:P/C fall inside the reference range. In HC dogs, a higher number of subjects with overt proteinuria was found while only 14% presented an increase only in the U:A/C. This fact, associated with a greater number of hypertensive dogs having HC rather than DM, could suggest a greater influence on renal function by the mechanisms involved in hypertension secondary to hypercortisolemia. Furthermore, it is possible that, in HC dogs, the diagnosis was more delayed than in DM dogs. However, the lack of a statistically significant correlation between hypertension and increased protein excretion as well as the apparently random distribution of proteinuric subjects in normotensive and hypertensive cases, imply that other factors besides hypertension are involved in causing proteinuria. Longitudinal studies are needed to further investigate the relationship between hypertension and proteinuria.
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Effects of the conflict between reason and passion in Bernard Mandeville’s moral, economic and political thought My PhD dissertation focuses on Bernard Mandeville (1670-1732), a Dutch philosopher who moved to London in his late twenties. The aspect of Mandeville’s thought I take into account in my research is the conflicting relation between reason and passions, and the consequences that Mandeville’s view of this conflict has in the development of his theory of human nature which, I argue, is what grounds his moral, economic and, above all, political theory. According to Mandeville, reason is fundamentally weak. Passions influence with more strength human actions, and, eventually, are the ones which motivate them. The role of reason is merely instrumental, restricted to finding appropriate means in order to reach the desired ends, which are capricious and inconstant, since they all come from unstable passions. Reason cannot take decisions meant to act in the long term, pursuing an object which has not a selfish and temporary nature. There is no possibility, thus, that men’s actions aim just to achieve a good and just society, without their interests being directly involved. The basically selfish root of every desire leads Mandeville to claim that there is neither benevolence nor altruism which guides human behaviour. Hence he expresses a judgement on the moral character of human beings, always busy with their self-satisfaction, and hardly ever considering what would be good on a wider perspective, including other people’s sake. The anthropological features ascribed to men by Mandeville, are those which lead him to prefer a political system where governors are not supposed to have particular abilities, either from an intellectual or from a moral point of view, and peace and order are preserved by the bureaucratic machine, which is meant to work with the least effort on the part of the politicians, and no big harm can be done even by corrupted or wicked governors. This system is adopted with an eye at remedying human deficiencies: Mandeville takes into primary account, when he thinks of how to build a peaceful and functioning society, that everyone is concerned with his selfish interest, and that the rationality of a single politician, or of a group of them belonging to a same generation, cannot find a good “solution” to govern men able to last over the long period, and to work in different ages. This implies a refusal of the Hobbesian theory of the pactum subjectionis, which has the character of a rational and definitive choice, and leads Mandeville to consider the order which arises spontaneously, without any plan or rational intervention.
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Heterocyclic compounds represent almost two-thirds of all the known organic compounds: they are widely distributed in nature and play a key role in a huge number of biologically important molecules including some of the most significant for human beings. A powerful tool for the synthesis of such compounds is the hetero Diels-Alder reaction (HDA), that involve a [4+2] cycloaddition reaction between heterodienes and suitable dienophiles. Among heterodienes to be used in such six-membered heterocyclic construction strategy, 3-trialkylsilyloxy-2-aza-1,3-dienes (Fig 1) has been demonstrated particularly attractive. In this thesis work, HDA reactions between 2-azadienes and carbonylic and/or olefinic dienophiles, are described. Moreover, substitution of conventional heating by the corresponding dielectric heating as been explored in the frame of Microwave-Assisted-Organic-Synthesis (MAOS) which constitutes an up-to-grade research field of great interest both from an academic and industrial point of view. Reaction of the azadiene 1 (Fig 1) will be described using as dienophiles carbonyl compounds as aldehyde and ketones. The six-membered adducts thus obtained (Scheme 1) have been elaborated to biologically active compounds like 1,3-aminols which constitutes the scaffold for a wide range of drugs (Prozac®, Duloxetine, Venlafaxine) with large applications in the treatment of severe diseases of nervous central system (NCS). Scheme 1 The reaction provides the formation of three new stereogenic centres (C-2; C-5; C-6). The diastereoselective outcome of these reactions has been deeply investigated by the use of various combination of achiral and chiral azadienes and aliphatic, aromatic or heteroaromatic aldehydes. The same approach, basically, has been used in the synthesis of piperidin-2-one scaffold substituting the carbonyl dienophile with an electron poor olefin. Scheme 2 As a matter of fact, this scaffold is present in a very large number of natural substances and, more interesting, is a required scaffold for an huge variety of biologically active compounds. Activated olefins bearing one or two sulfone groups, were choose as dienophiles both for the intrinsic characteristic flexibility of the “sulfone group” which may be easily removed or elaborated to more complex decorations of the heterocyclic ring, and for the electron poor property of this dienophiles which makes the resulting HDA reaction of the type “normal electron demand”. Synthesis of natural compounds like racemic (±)-Anabasine (alkaloid of Tobacco’s leaves) and (R)- and (S)-Conhydrine (alkaloid of Conium Maculatum’s seeds and leaves) and its congeners, are described (Fig 2).