1000 resultados para Monnaie unique européenne -- Opinion publique


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O presente relatório visa cumprir os requisitos da unidade curricular Dissertação, Projeto ou Estágio (DIPRE) do mestrado em Engenharia Civil do Instituto Superior de Engenharia do Porto (ISEP). O estágio curricular decorreu na empresa VPM - Vaz Pinto Mendes - Unipessoal Lda, sob o tema: “A avaliação imobiliária e a sua relação com o investimento”. A avaliação imobiliária visa determinar o valor associado aos bens imóveis. Pode ser aplicada a todo o tipo de bens imóveis, tais como: apartamentos e moradias uni e multifamiliares, espaços comerciais e de serviços, quintas, unidades hoteleiras e industriais, complexos desportivos, entre outros. A avaliação imobiliária poderá ser solicitada por parte de proprietários ou arrendatários dos imóveis, por empresas, tribunais, advogados e solicitadores. Apresenta diversos fins, tais como a determinação do valor de indemnização devido a expropriações, o financiamento hipotecário para compra ou construção de imóveis, partilhas, estudo de um investimento financeiro, intenção de venda ou arrendamento, efeitos fiscais ou apenas o simples conhecimento do valor aproximado das propriedades que se possui. O presente estudo visa abordar o atual mercado imobiliário nacional, o procedimento de realização de uma avaliação imobiliária e principalmente os métodos de avaliação tradicionais.

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Resumo: Os resultados das nossas investigações, apresentadas ao longo desta dissertação,contribuíram para a otimização do diagnóstico invasivo e não invasivo da osteodistrofia renal e permitiram evidenciar a relevância, para a expressão clínica e histológica da ODR, de algumas articularidades específicas da população hemodialisada, nomeadamente: a utilização de membranas de hemodiálise mais biocompatíveis e com elevada permeabilidade, o recurso a técnicas de hemodiafiltração com otimização da capacidade convectiva, as limitações dos marcadores bioquímicos de remodelação óssea ou a insuficiência / deficiência em vitamina D nativa (bem como os resultados da suplementação com esta vitamina). Testámos, pela primeira vez em doentes hemodialisados, novos marcadores da formação e reabsorção óssea, que validámos mediante a comparação com os resultados da histomorfometria óssea. No seu conjunto, e de forma integrada, as nossas investigações permitiram-nos: - Evidenciar a diminuição da expressão do recetor da PTH/PTHrP na cartilagem de crescimento, num modelo animal de IRC, o que explica, pelo menos em parte, o atraso de crescimento observado nesta patologia, bem como a diminuição da resposta à ação da PTH; - Demonstrar as vantagens da determinação da isoforma óssea da fosfatase alcalina, em relação à fosfatase alcalina total, no diagnóstico diferencial entre baixa e elevada remodelação óssea; - Utilizar, pela primeira vez em hemodialisados, a piridinolina e a desoxipiridinolina no diagnóstico da reabsorção óssea. Este foi o primeiro marcador sérico específico da atividade osteoclástica, utilizado com sucesso em doentes anúricos em hemodiálise. Evidenciámos uma excelente correlação destes dois marcadores bioquímicos com a superfície osteoclástica e com o número de osteoclastos/mm2;- Demonstrar as acentuadas limitações de outros marcadores da formação e reabsorção óssea (nomeadamente a osteocalcina, o propeptido carboxiterminal do procolagénio tipo I-PICP, e o Telopeptido do colagénio tipo I – ICTP) com base nas correlações entre os doseamentos séricos ou plasmáticos destes marcadores e a biópsia óssea com avaliação histomorfométrica; -Evidenciar as limitações induzidas pela sobrecarga alumínica na interpretação dos níveis séricos dos marcadores não invasivos da remodelação óssea;-Testar a eficácia e segurança da utilização de “microdoses” de desferroxamina na terapêutica da intoxicação alumínica, em doentes com acentuada exposição a este metal;-Demonstrar que os doentes hemodialisados cronicamente com dialisadores de poliacrilonitrilo (membranas de alta permeabilidade),apresentavam menor ativação osteoblástica e osteoclástica, que os doentes dialisados com membranas de cuprofano(baixa permeabilidade), sendo os níveis de iPTH semelhantes em ambos os grupos estudados. Estes resultados apontam para uma menor ativação da remodelação óssea quando se utilizam membranas de hemodiálise mais biocompatíveis e/ou de maior permeabilidade, o que se poderá relacionar com a ultrafiltração de mediadores da ativação celular ou com a menor ativação dos mecanismos estimuladores da remodelação óssea, por parte destas membranas. Entre os mediadores da remodelação óssea que demonstrámos serem relevantes e estarem aumentados no soro de hemodialisados com membranas de baixo fluxo, contam-se a beta-2-microglobulina (2-M) e algumas citoquinas, com ação estimuladora das linhagens celulares envolvidas na remodelação óssea. Demonstrámos igualmente uma correlação positiva dos níveis séricos de 2-M com os níveis séricos da osteocalcina, da isoenzima óssea da fosfatase alcalina (marcadores da formação óssea) e com os níveis séricos da piridinolina (marcador da reabsorção óssea). Os níveis séricos de 2-M correlacionaram-se ainda, de forma negativa, com o volume osteoide (matriz óssea não calcificada). Nestes doentes hemodialisados, demonstrámos a presença de níveis séricos aumentados da interleucina-1, do antagonista do recetor da interleucina-1, da interleucina-6 e do recetor solúvel da interleucina-6. Salientamos as relações inversas que observámos, por um lado entre os níveis de antagonista do recetor da interleucina-1 e a superfície osteoblástica, e por outro lado entre o rácio do recetor da interleucina-6 / interleucina-6 (IL6-r/IL6) e a superfície osteoclástica. De acordo com estes nossos resultados originais, entendemos que a interferência nos níveis circulantes e na ativação local destes mediadores poderá justificar, em grande parte, o aumento da prevalência de doença óssea adinâmica, descrita por nós e por outros grupos. Evidenciámos uma elevadíssima prevalência de doença adinâmica (>50% dos doentes), numa população de hemodialisados sem exposição prévia ao alumínio, tratados de acordo com os K/DOQI “guidelines” e que ao longo de um ano mantiveram níveis séricos de cálcio e de fósforo controlados. Consequentemente, os doentes tratados de forma otimizada apresentaram uma prevalência surpreendentemente elevada de doença adinâmica. Os nossos resultados (classificados com o grau de evidência máxima pelos peritos KDIGO) contribuíram para dar suporte à grande diferença nos guidelines K/DOQI (2003) e KDIGO (2009) no que respeita aos valores alvo da PTH. Estamos conscientes que de que o facto de termos uma percentagem tão elevada de doença óssea adinâmica nas nossas populações de hemodialisados, bem como a demonstração de que alguns doentes com valores de PTH intacta (2ª geração) de cerca de 600 pg/ml tinham doença óssea adinâmica, condicionaram os novos objetivos KDIGO para a PTH. Os nossos resultados suportam, em nossa opinião, a adequação e vantagem da utilização dos critérios da KDIGO em vez dos KDOQI. Tendo em conta que os primeiros definem objetivos para a PTH entre 2 e 9 vezes o limite superior do normal e não se comprometem com valores alvo absolutos e rígidos (definidos previamente nos KDOQI entre 150 e 300 pg/mL), esta nova abordagem parece-nos mais correta.Na nossa investigação clínica, caracterizámos ainda a população hemodialisada portuguesa no que respeita aos níveis séricos de calcidiol, identificando a população com suficiência, insuficiência ou deficiência em vitamina D3. Documentámos uma acentuada prevalência de insuficiência e mesmo de deficiência nesta vitamina, numa vasta população de hemodialisados, a qual, muito provavelmente, reflete de forma fidedigna, o que se pode observar na restante população de doentes portugueses IRC em estádio 5d (em diálise). Descrevemos, pela primeira vez em doentes hemodialisados, uma associação entre deficiência em calcidiol e a presença de fatores de risco cardiovascular (que têm sido identificados nos doentes urémicos). A nossa investigação conduziu-nos a resultados originais, ao identificar os níveis baixos de 25(OH)vitamina D3 como um provável fator de risco cardiovascular em hemodialisados, visto que a deficiência nesta vitamina se associou, de forma muito significativa, ao aumento da prevalência de calcificações vasculares, a inflamação, a pressão de pulso mais elevada, a hipertrofia ventricular esquerda, a insuficiência cardíaca e a níveis séricos aumentados de “BNP-Brain natriuretic peptide”. Finalmente, numa avaliação prospetiva, de intervenção terapêutica, corrigimos a insuficiência ou deficiência em 25(OH)vitamina D3 e demonstrámos que essa correção se associou a uma redução dos fatores de risco cardiovascular. Esta última intervenção foi totalmente inovadora, visto ser a primeira avaliação prospetiva da evolução dos fatores de risco cardiovasculares, em função da suplementação com vitamina D nativa, em doentes hemodialisados. Em resumo, pensamos que os resultados das nossas investigações, acima sumarizadas e apresentadas ao longo dos diversos capítulos desta dissertação,contribuiram para uma nova perspetiva da osteodistrofia renal e para recolocar o foco da atenção dos nefrologistas no tecido ósseo e no eixo paratormona – vitamina D – remodelação óssea. Este eixo surje claramente envolvido em múltiplos processos fisiopatológicos, que suportam a elevada morbilidade e mortalidade (nomeadamente de causa cardiovascular) observada nos doentes urémicos.---------ABSTRACT: The results of our research, presented throughout this thesis, contributed towards the optimisation of the invasive and non-invasive diagnosis of renal osteodystrophy. They have also highlighted the importance, to the clinical and histological expression of the ODR, of some specific characteristics of the haemodialysis population, including: the use of biocompatible high permeability haemodialysis membranes, the use of haemodiafiltration techniques with convection enhancement, as well as the limitations of biochemical markers of bone turnover or native vitamin D insufficiency/deficiency (along with the supplementation results of this vitamin). New bone formation and resorption markers, which were validated by comparison with the results of bone histomorphometry, have been tested for the first time on haemodialysis patients.As a whole, and in an integrated approach, our research enabled us to: - Show the decrease of the PTH/PTHrP receptor expression in cartilage growth, used on an IRC animal model, which explains, to some extent, not only the delayed growth observed in this pathology, but also the slow response to PTH. - Point out the advantages of the determination of bone isoform of alkaline phosphatase, in relation to the total alkaline phosphatase, in the differential diagnosis between low and high-bone turnover.- Use pyridinoline and deoxypyridinoline in the diagnosis of bone resorption for the first time on haemodialysis patients. This was the first specific serum market of the osteoclastic activity, which was successfully used on anuric patients undergoing haemodialysis treatment. We also observed an excellent correlation of these biochemical markers with the osteoclastic surface and the number of osteoclasts/mm2. - Demonstrate the sharp limitations of other markers of bone formation and resorption (namely osteocalcin, carboxyterminal propeptide of type I-PICP procollagen and telopeptide of type I-ICTP collagen) based on correlations between these markers’ serum or plasma assays and bone biopsy with histomorphometric assessment.-Show the limitations induced by aluminium overload in the interpretation of serum levels of bone remodelling non-invasive markers.-Test the efficacy and the safety of the use of deferoxamine “microdoses” for treatment of aluminium overload among patients with high levels of serum aluminium. - Demonstrate that patients with chronic haemodialysis dialysers of polyacrylonitrile (high permeability membranes) show a lower osteoblastic and osteoclastic activation than those undergoing dialysis with cuprofan membranes (low permeability), being the iPTH levels similar in both groups of patients. These findings point towards a lower activation of bone remodelling when using more biocompatible dialysis membranes and/or of higher permeability, which may relate to the ultrafiltration of cell activation mediators or to the lower activation of the stimulating mechanisms of bone remodelling, regarding the membranes. Beta-2-microglobulin (2-M) and some cytokines that play a role/participate in bone remodelling are among the bone remodelling mediators, which we demonstrated to be relevant and to be increased in the serum of haemodialysis with low flow membranes. We also proved that there is a positive correlation of serum 2-M levels not only with serum osteocalcin levels, of the bone isoenzyme of alkaline phosphatase (bone forming markers), but also with levels of serum pyridinoline (bone resorption marker).Serum 2-M levels correlate negatively with the volume of osteoid (uncalcified bone matrix). We also demonstrated the presence of elevated serum levels of interleukin-1,interleukin-1 receptor antagonist, interleukin-6 and soluble interleukin-6 receptor in haemodialysis patients. We stress the inverse relationship which we observed on one hand between the interleukin-1 receptor antagonist levels and the osteoblastic surface and on the other between the ratio of interleukin-6 receptor / interleukin-6 (IL6-r/IL6) and the osteoblastic surface. According to these unique findings, we believe that the interference in the circulating levels and in the local activation of these mediators may partly explain the rising prevalence of adynamic bone disease. A high prevalence of adynamic disease has also been observed in a haemodialysis population (>50% of patients) with no previous exposure to aluminium. The patients were treated according to K/DOQI guidelines and maintained controlled serum calcium and phosphorus levels over one year. As a result, the patients who received optimised treatment showed a surprisingly high prevalence of adynamic disease. Our results, which were ranked with the highest degree of evidence by KDIGO experts, contributed to the great difference regarding the target values of PTH in the K/DOQI (2003) and KDIGO (2009) guidelines. We are aware that the finding of such a high percentage of adynamic bone disease in our haemodialysis population, as well as the evidence that some patients with intact PTH values (2nd generation) of 600 pg/ml suffered from adynamic bone disease, have hindered, the new KDIGO objectives to PTH.In our opinion, our results support the suitability and the advantage of using KDIGO criteria instead of KDOQI. This seems to be the right approach when taking into consideration that KDIGO sets objectives to PTH between 2 and 9 times the normal upper limit and does not compromise with the rigid and absolute target values (between 150 and 300 pg/mL) previously defined by KDOQI. In our clinical research, the Portuguese haemodialysis population was characterised in terms of serum clacidiol levels and identified as having vitamin D3 sufficiency, insufficiency or deficiency. It was also recorded the prevalence of severe vitamin D3 insufficiency and even deficiency in a large haemodialysis population, which most likely provides a reliable picture of the rest of the population in IRC Portuguese patients with 5d stage (undergoing dialysis). We described for the first time in aemosialysis patients an association between calcidiol deficiency and the presence of ardiovascular risk factors, (which have been identified on uraemic patients).Our research led us to unique findings by having identified the low levels of 25(OH) vitamin D3 as a likely cardiovascular risk factor in patients undergoing haemodialysis treatment, given that deficiency in this vitamin has been significantly associated not only with a rise in the prevalence of vascular calcifications, but also inflammation, left ventricular hypertrophy, high pulse pressure and high serum BNPBrain natriuretic peptide levels. Finally, based on a prospective assessment of therapeutic intervention, 25(OH)vitamin D3 insufficiency or deficiency was corrected and we were able to demonstrate that this same correction was associated with a reduction in cardiovascular risk factors. This was a forward-looking intervention regarding the supplementation of native vitamin D in haemodialysis patients, since it was the first prospective assessment of the evolution of cardiovascular risk factors. In short, the results of our research, summarised above and presented throughout the various chapters of this thesis, contributed towards a new perspective of the renal osteodystrophy and also to draw the nephrologists’ attention to the bone tissue and to the axis PTH – vitamin D – bone remodelling. This axis appears clearly involved in multiple physiopathological processes, which support the high morbidity and mortality rate, (particularly of cardiovascular causes), observed in uraemic patients.

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RESUMO: A saúde pública deve estar atenta aos contextos e às mudanças sociais, políticas, económicas, científicas e tecnológicas com que se confrontam constantemente as comunidades, particularmente em situações de grandes transformações como o momento que a União Europeia atravessa. A urbanização é provavelmente a mudança demográfica mais importante das últimas décadas. Tendo importantes repercussões sobre a saúde mental, é importante desenvolver a investigação neste domínio, de forma multidisciplinar e integrando a compreensão dos diferentes determinantes sociais, psicológicos e físicos. As políticas de saúde mental tornaram-se uma parte importante da política social e da sociedade de bem-estar, em particular se considerarmos a urbanização das nossas comunidades. Considerar a saúde mental em espaço urbano é fundamentalmente estudar como um espaço particular pode influenciar a saúde. Baseado nesta reflexão, desenvolveu-se uma investigação participada de base comunitária, com recurso a uma metodologia de estudo de caso. Recorreu-se a dezenas de documentos de referência local, registos em arquivo, à observação direta, à observação participante e à observação in loco do espaço urbano. Foi utilizada uma amostragem em bola de neve, estratificada, para selecionar 697 habitantes de uma cidade da área metropolitana de Lisboa. Estes habitantes foram entrevistados por 42 entrevistadores, previamente formados, assim como foram enviados questionários online dirigidos aos professores (196) e aos Técnicos Superiores de Serviço Social (12) em exercício no espaço urbano em estudo, para a caraterização sociodemográfica e para avaliação de indicadores de saúde, de indicadores relacionados com a saúde e de indicadores estruturais de saúde mental. Os resultados mostraram um espaço urbano promotor de saúde estrutura-se para capacitar os seus cidadãos a se integrarem ativamente no funcionamento da sua comunidade. Foram identificadas algumas caraterísticas como 1) o início do processo de promoção da saúde mental ser o mais precoce possível; 2) a participação comunitária ativa, num sentimento de segurança individual e comunitária, envolvendo estruturas governamentais e não-governamentais; 3) a solidariedade e a inclusão, promovendo o voluntariado e a promoção do suporte social e desenvolvendo a coesão social; 4) o reconhecimento das necessidades expressas pelos habitantes; 5) a identificação de respostas para a conciliação entre vida pessoal, familiar e profissional; 6) as estruturas de acompanhamento dos grupos sociais mais desfavorecidos; 7) as estratégias de combate ao isolamento envolvendo a população sénior e outros grupos minoritários ativamente no processo de reorganização do seu funcionamento social; 8) uma efetiva governança e gestão relacional por parte dos poderes locais, centrando a vida quotidiana da comunidade nas pessoas. A investigação participada de base comunitária constitui um instrumento útil e eficaz no desenho de planos locais de promoção da saúde mental para encontrar respostas ao desafio em saúde pública: a saúde mental e a urbanização.

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In his Answer to the Question: What is Enlightenment (1784), Kant puts forward his belief that the vocation to think freely, which humankind is endowed with, is bound to make sure that “the public use of reason” will at last act “even on the fundamental principles of government and the state [will] find it agreeable to treat man – who is now more than a machine – in accord with his dignity”. The critical reference to La Mettrie (1747), by opposing the machine to human dignity, will echo, in the dawn of the 20th century, in Bergson’s attempt to explain humor. Besides being exclusive to humans, humor is also a social phenomenon. Freud (1905) assures that pleasure originated by humor is collective, it results from a “social process”: jokes need an audience, a “third party”, in order to work and have fun. Assuming humor as a social and cultural phenomenon, this paper intends to sustain that it played a role in the framing of the public sphere and of public opinion in Portugal during the transition from Absolute Monarchy to Liberalism. The search for the conditions which made possible the critical exercise of sociability is at the root of the creation of the public sphere in the sense developed by Habermas (1962), whose perspective, however, has been questioned by those who point 2 out the alleged idealism of the concept – as opposed, for example, to Bakhtin (1970), whose work stresses diversity and pluralism. This notwithstanding, the concept of public sphere is crucial to the building of public opinion, which is, in turn, indissoluble from the principle of publicity, as demonstrated by Bobbio (1985). This paper discusses the historical evolution of the concept of public opinion from Ancient Greece doxa, through Machiavelli’s “humors” (1532), the origin of the expression in Montaigne (1580) and the contributions of Hobbes (1651), Locke (1690), Swift (1729), Rousseau (1762) or Hume (1777), up to the reflection of Lippman (1922) and Bourdieu’s critique (1984). It maintains that humor, as it appears in Portuguese printed periodicals from 1797 (when Almocreve de Petas was published for the first time) to the end of the civil war (1834) – especially in those edited by José Daniel Rodrigues da Costa but also in O Piolho Viajante, by António Manuel Policarpo da Silva, or in the ones written by José Agostinho de Macedo, as well as in a political “elite minded” periodical such as Correio Braziliense –, contributed to the framing of the public sphere and of public opinion in Portugal.

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The emergence of new fungal pathogens, either of plants or animals, and the increasing number of reported cases of resistant human pathogenic strains to the available antifungal drugs reinforces the need for better understanding the biology of filamentous fungi. Conventional drugs target components of the fungal membrane or cell wall, therefore identifying novel intracellular targets, yet unique to fungi, is a global priority.(...)

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The case is based on Garland, a 240 years old Portuguese family business, now owned by the Dawson family. It focuses on a decision made 50 years ago, aligned with what had been the company’s history, about the ownership rules for family members, which influences the ownership structure of the firm. It addresses the main issues about ownership in family businesses, and tackles the problem of succession planning and fair process. It contains a teaching note to support the utilization of the case in a classroom context, with learning objectives, target audience, a teaching plan, questions and proposed answers, and theory that relates to the case. It is also complemented with an epilogue and an overview of the case.

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It is well known that color coding facilitates search and iden- tification in real-life tasks. The aim of this work was to compare reac- tion times for normal color and dichromatic observers in a visual search experiment. A unique distracter color was used to avoid abnormal color vision vulnerability to background complexity. Reaction times for nor- mal color observers and dichromats were estimated for 2◦ central vision at 48 directions around a white point in CIE L∗a∗b∗ color space for systematic examination on the mechanisms of dichromatic color percep- tion. The results show that mean search times for dichromats were twice larger compared to the normal color observers and for all directions. The difference between the copunctual confusion lines and the confusion direction measure experimentally was 5.5◦ for protanopes and 7.5◦ for deuteranopes.

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A patient with heart failure and acute atrial fibrillation received the final diagnosis of atrial infarction associated with ventricular infarction based on clinical findings of ischemia in association with atrial fibrillation and heart failure (mechanisms probably involved: contractile dysfunction and loss of atrial contribution). Although a transesophageal echocardiography, which could refine the diagnosis of anatomic abnormalities, was not performed, all evidence led to the diagnosis of atrial involvement. Electrocardiographic findings were consistent with Liu's major criterion 3. Therapy with digitalis, quinidine and angiotensin-converting enzyme inhibitors was chosen, as the patient had acute pulmonary edema. The use of beta-blockers and verapamil was restricted. No other complications, such as thrombo-embolism or atrial rupture, were noted.

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In thee present paper the classical concept of the corpuscular gene is dissected out in order to show the inconsistency of some genetical and cytological explanations based on it. The author begins by asking how do the genes perform their specific functions. Genetists say that colour in plants is sometimes due to the presence in the cytoplam of epidermal cells of an organic complex belonging to the anthocyanins and that this complex is produced by genes. The author then asks how can a gene produce an anthocyanin ? In accordance to Haldane's view the first product of a gene may be a free copy of the gene itself which is abandoned to the nucleus and then to the cytoplasm where it enters into reaction with other gene products. If, thus, the different substances which react in the cell for preparing the characters of the organism are copies of the genes then the chromosome must be very extravagant a thing : chain of the most diverse and heterogeneous substances (the genes) like agglutinins, precipitins, antibodies, hormones, erzyms, coenzyms, proteins, hydrocarbons, acids, bases, salts, water soluble and insoluble substances ! It would be very extrange that so a lot of chemical genes should not react with each other. remaining on the contrary, indefinitely the same in spite of the possibility of approaching and touching due to the stato of extreme distension of the chromosomes mouving within the fluid medium of the resting nucleus. If a given medium becomes acid in virtue of the presence of a free copy of an acid gene, then gene and character must be essentially the same thing and the difference between genotype and phenotype disappears, epigenesis gives up its place to preformation, and genetics goes back to its most remote beginnings. The author discusses the complete lack of arguments in support of the view that genes are corpuscular entities. To show the emharracing situation of the genetist who defends the idea of corpuscular genes, Dobzhansky's (1944) assertions that "Discrete entities like genes may be integrated into systems, the chromosomes, functioning as such. The existence of organs and tissues does not preclude their cellular organization" are discussed. In the opinion of the present writer, affirmations as such abrogate one of the most important characteristics of the genes, that is, their functional independence. Indeed, if the genes are independent, each one being capable of passing through mutational alterations or separating from its neighbours without changing them as Dobzhansky says, then the chromosome, genetically speaking, does not constitute a system. If on the other hand, theh chromosome be really a system it will suffer, as such, the influence of the alteration or suppression of the elements integrating it, and in this case the genes cannot be independent. We have therefore to decide : either the chromosome is. a system and th genes are not independent, or the genes are independent and the chromosome is not a syntem. What cannot surely exist is a system (the chromosome) formed by independent organs (the genes), as Dobzhansky admits. The parallel made by Dobzhansky between chromosomes and tissues seems to the author to be inadequate because we cannot compare heterogeneous things like a chromosome considered as a system made up by different organs (the genes), with a tissue formed, as we know, by the same organs (the cells) represented many times. The writer considers the chromosome as a true system and therefore gives no credit to the genes as independent elements. Genetists explain position effects in the following way : The products elaborated by the genes react with each other or with substances previously formed in the cell by the action of other gene products. Supposing that of two neighbouring genes A and B, the former reacts with a certain substance of the cellular medium (X) giving a product C which will suffer the action, of the latter (B). it follows that if the gene changes its position to a place far apart from A, the product it elaborates will spend more time for entering into contact with the substance C resulting from the action of A upon X, whose concentration is greater in the proximities of A. In this condition another gene produtc may anticipate the product of B in reacting with C, the normal course of reactions being altered from this time up. Let we see how many incongruencies and contradictions exist in such an explanation. Firstly, it has been established by genetists that the reaction due.to gene activities are specific and develop in a definite order, so that, each reaction prepares the medium for the following. Therefore, if the medium C resulting from the action of A upon x is the specific medium for the activity of B, it follows that no other gene, in consequence of its specificity, can work in this medium. It is only after the interference of B, changing the medium, that a new gene may enter into action. Since the genotype has not been modified by the change of the place of the gene, it is evident that the unique result we have to attend is a little delay without seious consequence in the beginning of the reaction of the product of B With its specific substratum C. This delay would be largely compensated by a greater amount of the substance C which the product of B should found already prepared. Moreover, the explanation did not take into account the fact that the genes work in the resting nucleus and that in this stage the chromosomes, very long and thin, form a network plunged into the nuclear sap. in which they are surely not still, changing from cell to cell and In the same cell from time to time, the distance separating any two genes of the same chromosome or of different ones. The idea that the genes may react directly with each other and not by means of their products, would lead to the concept of Goidschmidt and Piza, in accordance to which the chromosomes function as wholes. Really, if a gene B, accustomed to work between A and C (as for instance in the chromosome ABCDEF), passes to function differently only because an inversion has transferred it to the neighbourhood of F (as in AEDOBF), the gene F must equally be changed since we cannot almH that, of two reacting genes, only one is modified The genes E and A will be altered in the same way due to the change of place-of the former. Assuming that any modification in a gene causes a compensatory modification in its neighbour in order to re-establich the equilibrium of the reactions, we conclude that all the genes are modified in consequence of an inversion. The same would happen by mutations. The transformation of B into B' would changeA and C into A' and C respectively. The latter, reacting withD would transform it into D' and soon the whole chromosome would be modified. A localized change would therefore transform a primitive whole T into a new one T', as Piza pretends. The attraction point-to-point by the chromosomes is denied by the nresent writer. Arguments and facts favouring the view that chromosomes attract one another as wholes are presented. A fact which in the opinion of the author compromises sereously the idea of specific attraction gene-to-gene is found inthe behavior of the mutated gene. As we know, in homozygosis, the spme gene is represented twice in corresponding loci of the chromosomes. A mutation in one of them, sometimes so strong that it is capable of changing one sex into the opposite one or even killing the individual, has, notwithstading that, no effect on the previously existing mutual attraction of the corresponding loci. It seems reasonable to conclude that, if the genes A and A attract one another specifically, the attraction will disappear in consequence of the mutation. But, as in heterozygosis the genes continue to attract in the same way as before, it follows that the attraction is not specific and therefore does not be a gene attribute. Since homologous genes attract one another whatever their constitution, how do we understand the lack cf attraction between non homologous genes or between the genes of the same chromosome ? Cnromosome pairing is considered as being submitted to the same principles which govern gametes copulation or conjugation of Ciliata. Modern researches on the mating types of Ciliata offer a solid ground for such an intepretation. Chromosomes conjugate like Ciliata of the same variety, but of different mating types. In a cell there are n different sorts of chromosomes comparable to the varieties of Ciliata of the same species which do not mate. Of each sort there are in the cell only two chromosomes belonging to different mating types (homologous chromosomes). The chromosomes which will conjugate (belonging to the same "variety" but to different "mating types") produce a gamone-like substance that promotes their union, being without action upon the other chromosomes. In this simple way a single substance brings forth the same result that in the case of point-to-point attraction would be reached through the cooperation of as many different substances as the genes present in the chromosome. The chromosomes like the Ciliata, divide many times before they conjugate. (Gonial chromosomes) Like the Ciliata, when they reach maturity, they copulate. (Cyte chromosomes). Again, like the Ciliata which aggregate into clumps before mating, the chrorrasrmes join together in one side of the nucleus before pairing. (.Synizesis). Like the Ciliata which come out from the clumps paired two by two, the chromosomes leave the synizesis knot also in pairs. (Pachytene) The chromosomes, like the Ciliata, begin pairing at any part of their body. After some time the latter adjust their mouths, the former their kinetochores. During conjugation the Ciliata as well as the chromosomes exchange parts. Finally, the ones as the others separate to initiate a new cycle of divisions. It seems to the author that the analogies are to many to be overlooked. When two chemical compounds react with one another, both are transformed and new products appear at the and of the reaction. In the reaction in which the protoplasm takes place, a sharp difference is to be noted. The protoplasm, contrarily to what happens with the chemical substances, does not enter directly into reaction, but by means of products of its physiological activities. More than that while the compounds with Wich it reacts are changed, it preserves indefinitely its constitution. Here is one of the most important differences in the behavior of living and lifeless matter. Genes, accordingly, do not alter their constitution when they enter into reaction. Genetists contradict themselves when they affirm, on the one hand, that genes are entities which maintain indefinitely their chemical composition, and on the other hand, that mutation is a change in the chemica composition of the genes. They are thus conferring to the genes properties of the living and the lifeless substances. The protoplasm, as we know, without changing its composition, can synthesize different kinds of compounds as enzyms, hormones, and the like. A mutation, in the opinion of the writer would then be a new property acquired by the protoplasm without altering its chemical composition. With regard to the activities of the enzyms In the cells, the author writes : Due to the specificity of the enzyms we have that what determines the order in which they will enter into play is the chemical composition of the substances appearing in the protoplasm. Suppose that a nucleoproteln comes in relation to a protoplasm in which the following enzyms are present: a protease which breaks the nucleoproteln into protein and nucleic acid; a polynucleotidase which fragments the nucleic acid into nucleotids; a nucleotidase which decomposes the nucleotids into nucleoids and phosphoric acid; and, finally, a nucleosidase which attacs the nucleosids with production of sugar and purin or pyramidin bases. Now, it is evident that none of the enzyms which act on the nucleic acid and its products can enter into activity before the decomposition of the nucleoproteln by the protease present in the medium takes place. Leikewise, the nucleosidase cannot works without the nucleotidase previously decomposing the nucleotids, neither the latter can act before the entering into activity of the polynucleotidase for liberating the nucleotids. The number of enzyms which may work at a time depends upon the substances present m the protoplasm. The start and the end of enzym activities, the direction of the reactions toward the decomposition or the synthesis of chemical compounds, the duration of the reactions, all are in the dependence respectively o fthe nature of the substances, of the end products being left in, or retired from the medium, and of the amount of material present. The velocity of the reaction is conditioned by different factors as temperature, pH of the medium, and others. Genetists fall again into contradiction when they say that genes act like enzyms, controlling the reactions in the cells. They do not remember that to cintroll a reaction means to mark its beginning, to determine its direction, to regulate its velocity, and to stop it Enzyms, as we have seen, enjoy none of these properties improperly attributed to them. If, therefore, genes work like enzyms, they do not controll reactions, being, on the contrary, controlled by substances and conditions present in the protoplasm. A gene, like en enzym, cannot go into play, in the absence of the substance to which it is specific. Tne genes are considered as having two roles in the organism one preparing the characters attributed to them and other, preparing the medium for the activities of other genes. At the first glance it seems that only the former is specific. But, if we consider that each gene acts only when the appropriated medium is prepared for it, it follows that the medium is as specific to the gene as the gene to the medium. The author concludes from the analysis of the manner in which genes perform their function, that all the genes work at the same time anywhere in the organism, and that every character results from the activities of all the genes. A gene does therefore not await for a given medium because it is always in the appropriated medium. If the substratum in which it opperates changes, its activity changes correspondingly. Genes are permanently at work. It is true that they attend for an adequate medium to develop a certain actvity. But this does not mean that it is resting while the required cellular environment is being prepared. It never rests. While attending for certain conditions, it opperates in the previous enes It passes from medium to medium, from activity to activity, without stopping anywhere. Genetists are acquainted with situations in which the attended results do not appear. To solve these situations they use to make appeal to the interference of other genes (modifiers, suppressors, activators, intensifiers, dilutors, a. s. o.), nothing else doing in this manner than displacing the problem. To make genetcal systems function genetists confer to their hypothetical entities truly miraculous faculties. To affirm as they do w'th so great a simplicity, that a gene produces an anthocyanin, an enzym, a hormone, or the like, is attribute to the gene activities that onlv very complex structures like cells or glands would be capable of producing Genetists try to avoid this difficulty advancing that the gene works in collaboration with all the other genes as well as with the cytoplasm. Of course, such an affirmation merely means that what works at each time is not the gene, but the whole cell. Consequently, if it is the whole cell which is at work in every situation, it follows that the complete set of genes are permanently in activity, their activity changing in accordance with the part of the organism in which they are working. Transplantation experiments carried out between creeper and normal fowl embryos are discussed in order to show that there is ro local gene action, at least in some cases in which genetists use to recognize such an action. The author thinks that the pleiotropism concept should be applied only to the effects and not to the causes. A pleiotropic gene would be one that in a single actuation upon a more primitive structure were capable of producing by means of secondary influences a multiple effect This definition, however, does not preclude localized gene action, only displacing it. But, if genetics goes back to the egg and puts in it the starting point for all events which in course of development finish by producing the visible characters of the organism, this will signify a great progress. From the analysis of the results of the study of the phenocopies the author concludes that agents other than genes being also capaole of determining the same characters as the genes, these entities lose much of their credit as the unique makers of the organism. Insisting about some points already discussed, the author lays once more stress upon the manner in which the genes exercise their activities, emphasizing that the complete set of genes works jointly in collaboration with the other elements of the cell, and that this work changes with development in the different parts of the organism. To defend this point of view the author starts fron the premiss that a nerve cell is different from a muscle cell. Taking this for granted the author continues saying that those cells have been differentiated as systems, that is all their parts have been changed during development. The nucleus of the nerve cell is therefore different from the nucleus of the muscle cell not only in shape, but also in function. Though fundamentally formed by th same parts, these cells differ integrally from one another by the specialization. Without losing anyone of its essenial properties the protoplasm differentiates itself into distinct kinds of cells, as the living beings differentiate into species. The modified cells within the organism are comparable to the modified organisms within the species. A nervo and a muscle cell of the same organism are therefore like two species originated from a common ancestor : integrally distinct. Like the cytoplasm, the nucleus of a nerve cell differs from the one of a muscle cell in all pecularities and accordingly, nerve cell chromosomes are different from muscle cell chromosomes. We cannot understand differentiation of a part only of a cell. The differentiation must be of the whole cell as a system. When a cell in the course of development becomes a nerve cell or a muscle cell , it undoubtedly acquires nerve cell or muscle cell cytoplasm and nucleus respectively. It is not admissible that the cytoplasm has been changed r.lone, the nucleus remaining the same in both kinds of cells. It is therefore legitimate to conclude that nerve ceil ha.s nerve cell chromosomes and muscle cell, muscle cell chromosomes. Consequently, the genes, representing as they do, specific functions of the chromossomes, are different in different sorts of cells. After having discussed the development of the Amphibian egg on the light of modern researches, the author says : We have seen till now that the development of the egg is almost finished and the larva about to become a free-swimming tadepole and, notwithstanding this, the genes have not yet entered with their specific work. If the haed and tail position is determined without the concourse of the genes; if dorso-ventrality and bilaterality of the embryo are not due to specific gene actions; if the unequal division of the blastula cells, the different speed with which the cells multiply in each hemisphere, and the differential repartition of the substances present in the cytoplasm, all this do not depend on genes; if gastrulation, neurulation. division of the embryo body into morphogenetic fields, definitive determination of primordia, and histological differentiation of the organism go on without the specific cooperation of the genes, it is the case of asking to what then the genes serve ? Based on the mechanism of plant galls formation by gall insects and on the manner in which organizers and their products exercise their activities in the developing organism, the author interprets gene action in the following way : The genes alter structures which have been formed without their specific intervention. Working in one substratum whose existence does not depend o nthem, the genes would be capable of modelling in it the particularities which make it characteristic for a given individual. Thus, the tegument of an animal, as a fundamental structure of the organism, is not due to gene action, but the presence or absence of hair, scales, tubercles, spines, the colour or any other particularities of the skin, may be decided by the genes. The organizer decides whether a primordium will be eye or gill. The details of these organs, however, are left to the genetic potentiality of the tissue which received the induction. For instance, Urodele mouth organizer induces Anura presumptive epidermis to develop into mouth. But, this mouth will be farhioned in the Anura manner. Finalizing the author presents his own concept of the genes. The genes are not independent material particles charged with specific activities, but specific functions of the whole chromosome. To say that a given chromosome has n genes means that this chromonome, in different circumstances, may exercise n distinct activities. Thus, under the influence of a leg evocator the chromosome, as whole, develops its "leg" activity, while wbitm the field of influence of an eye evocator it will develop its "eye" activity. Translocations, deficiencies and inversions will transform more or less deeply a whole into another one, This new whole may continue to produce the same activities it had formerly in addition to those wich may have been induced by the grafted fragment, may lose some functions or acquire entirely new properties, that is, properties that none of them had previously The theoretical possibility of the chromosomes acquiring new genetical properties in consequence of an exchange of parts postulated by the present writer has been experimentally confirmed by Dobzhansky, who verified that, when any two Drosophila pseudoobscura II - chromosomes exchange parts, the chossover chromosomes show new "synthetic" genetical effects.

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Stink bugs are seed/fruit sucking insects feeding on an array of host plants. Among them, an exotic tree called privet, Ligustrum lucidum Ait. (Oleaceae), is very common in the urban areas of the Brazilian subtropics, where it is utilized as food source and shelter for over a decem species of bugs, year round. The species composition, their performance and abundance on this host, and possible causes for this association are discussed and illustrated.