875 resultados para 770 Photography
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Atualmente a fotografia encontra-se amplamente disseminada numa variedade de gneros e subgneros, de prticas e usos em contextos diversos. O estatuto artstico que lhe hoje reconhecido no obsta prtica generalizada por parte de fotgrafos amadores ou mesmo meros utilizadores, conferindo fotografia um carter ambivalente, que apontamos aqui como trao caraterstico. O objetivo desta investigao contribuir para o desenvolvimento do campo de estudo da fotografia, nomeadamente da fotografia do privado. Este gnero de baixa qualidade, de parcas preocupaes estticas, mas de grande valor afetivo, foi durante muito tempo marginalizado nos estudos fotogrficos, tendo s recentemente vindo a ser alvo de ateno. Propomo-nos, assim, contribuir para uma teorizao que permita a compreenso e mediao da fotografia enquanto prtica social do foro privado e fenmeno cultural em ascenso.
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Abstract: INTRODUCTION Risk of schistosomiasis expansion to semi-arid northeastern Brazil under the influence of the Integration Project of the So Francisco River (IPSFR) was assessed. METHODS: Stool examinations of schoolchildren, epidemiological investigation, and survey of the local host snail Biomphalaria straminea were performed in five IPSFR municipalities. RESULTS Six of 4,770 examined schoolchildren were egg-positive for Schistosoma mansoni. Biomphalaria straminea was widespread, but not naturally infected with S. mansoni. Snails experimentally exposed to two laboratory S. mansoni strains yielded infection indices of 1-4.5%. CONCLUSIONS: There is evidence of active schistosomiasis transmission in the area; thus, intensive surveillance actions are required.
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Este trabalho de investigao comeou por ser estruturado em torno de quatro grandes captulos (quatro grandes linhas de orientao temtica), todos eles amplamente desenvolvidos no sentido de podermos cartografar alguns dos principais territrios e sintomas da arte contempornea, sendo certo tambm, que cada um deles assenta precisamente nos princpios de uma estrutura malevel que, para todos os efeitos, se encontra em processo de construo (work in progress), neste caso, graas plasticidade do corpo, do espao, da imagem e do uso criativo das tecnologias digitais, no mbito das quais, alis, tudo se parece produzir, transformar e disseminar hoje em dia nossa volta (quase como se de uma autntica viagem interactiva se tratasse). Por isso, a partir daqui, todo o esforo que se segue procurar ensaiar uma hiptese de trabalho (desenvolver uma investigao) que, porventura, nos permita desbravar alguns caminhos em direco aos interminveis tneis do futuro, sempre na expectativa de podermos dar forma, funo e sentido a um desejo irreprimvel de liberdade criativa, pois, a arte contempornea tem essa extraordinria capacidade de nos transportar para muitos outros lugares do mundo, to reais e imaginrios como a nossa prpria vida. Assim sendo, h que sumariar algumas das principais etapas a desenvolver ao longo desta investigao. Ora, num primeiro momento, comearemos por reflectir sobre o conceito alargado de crise (a crise da modernidade), para logo de seguida podermos abordar a questo da crise das antigas categorias estticas, questionando assim, para todos os efeitos, quer o conceito de belo (Plato) e de gosto (Kant), quer ainda o conceito de forma (Foccilon), no s no sentido de tentarmos compreender algumas das principais razes que tero estado na origem do chamado fim da arte (Hegel), mas tambm algumas daquelas que tero conduzido estetizao generalizada da experincia contempornea e sua respectiva disseminao pelas mais variadas plataformas digitais. Num segundo momento, procuraremos reflectir sobre alguns dos principais problemas da inquietante histria das imagens, nomeadamente para tentarmos perceber como que todas estas transformaes tcnicas (ligadas ao aparecimento da fotografia, do cinema, do vdeo, do computador e da internet) tero contribudo para o processo de instaurao e respectivo alargamento daquilo que todos ns ficaramos a conhecer como a nova era da imagem, ou a imagem na era da sua prpria reprodutibilidade tcnica (Benjamin), pois, s assim que conseguiremos interrogar este imparvel processo de movimentao, fragmentao, disseminao, simulao e interaco das mais variadas formas de vida (Nietzsche, Agamben). Entretanto, chegados ao terceiro grande momento, interessa-nos percepcionar a arte contempornea como uma espcie de plataforma interactiva que, por sua vez, nos levar a interpelar alguns dos principais dispositivos metafricos e experimentais da viagem, neste caso, da viagem enquanto linha facilitadora de acesso arte, cultura e vida contempornea em geral, ou seja, todo um processo de reflexo que nos incitar a cartografar alguns dos mais atractivos sintomas provenientes da esttica do flneur (na perspectiva de Rimbaud, Baudelaire, Long e Benjamin) e, consequentemente, a convocar algumas das principais sensaes decorrentes da experincia altamente sedutora daqueles que vivem mergulhados na rbita interactiva do ciberespao (na condio de ciberflneurs), quase como se o mundo inteiro, agora, fosse to somente um espao potico inteiramente navegvel (Manovich). Por fim, no quarto e ltimo momento, procuraremos fazer uma profunda reflexo sobre a inquietante histria do corpo, principalmente com o objectivo de reforar a ideia de que apesar das suas inmeras fragilidades biolgicas (um ser que adoece e morre), o corpo continua a ser uma das categorias mais persistentes de toda a cultura ocidental (Ieda Tucherman), no s porque ele resistiu a todas as transformaes que lhe foram impostas historicamente, mas tambm porque ele se soube reinventar e readaptar pacientemente face a todas essas transformaes histricas. Sinal evidente de que a sua plasticidade lhe iria conferir, principalmente a partir do sculo XX (o sculo do corpo) um estatuto terico e performativo verdadeiramente especial. To especial, alis, que basta termos uma noo, mesmo que breve, da sua inquietante histria para percebermos imediatamente a extraordinria importncia dalgumas das suas mais variadas transformaes, atraces, ligaes e exibies ao longo das ltimas dcadas, nomeadamente sob o efeito criativo das tecnologias digitais (no mbito das quais se processam algumas das mais interessantes operaes de dinamizao cultural e artstica do nosso tempo). Em suma, esperamos sinceramente que este trabalho de investigao possa vir a contribuir para o processo de alargamento das fronteiras cada vez mais incertas, dinmicas e interactivas do conhecimento daquilo que parece constituir, hoje em dia, o jogo fundamental da nossa contemporaneidade.
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Com esta investigao pretende-se caracterizar a relao indissocivel entre Histria e Fotografia, reconhecendo as mltiplas formas de manipulao e respectivos mecanismos de hierarquizao de poder, que no apenas determinam o desenvolvimento da sua produo, arquivo e recepo, como desvendam uma constelao de ligaes disciplinares, tcnicas e polticas que potenciam e moldam o seu sentido. Esta problemtica analisada no contexto portugus, a partir das prticas de exposio, publicao e coleco fotogrfica e consequente ajuste do discurso terico e crtico nas dcadas de 1980 e 1990, adoptando como eixo de pesquisa o trabalho de investigao e historiografia desenvolvido entre 1973 e 1998 por Antnio Sena e, especificamente, o modo como aplica a Histria (de um meio) como hiperdocumento. O filme Olho de Vidro, uma Histria da Fotografia (1982), realizado por Antnio Sena e Margarida Gil, as iniciativas fotogrficas desenvolvidas pela associao ether/vale tudo menos tirar olhos entre 1982 e 1994, a criao da base de dados Luzitnia/ ether pix database e as publicaes Uma Histria de Fotografia (1991) e Histria da Imagem Fotogrfica em Portugal, 1839-1997 (1998) da autoria de Antnio Sena, formam o corpus do nosso estudo de caso.
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Tese de Doutoramento em Cincias da Comunicao
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The main features of most components consist of simple basic functional geometries: planes, cylinders, spheres and cones. Shape and position recognition of these geometries is essential for dimensional characterization of components, and represent an important contribution in the life cycle of the product, concerning in particular the manufacturing and inspection processes of the final product. This work aims to establish an algorithm to automatically recognize such geometries, without operator intervention. Using differential geometry large volumes of data can be treated and the basic functional geometries to be dealt recognized. The original data can be obtained by rapid acquisition methods, such as 3D survey or photography, and then converted into Cartesian coordinates. The satisfaction of intrinsic decision conditions allows different geometries to be fast identified, without operator intervention. Since inspection is generally a time consuming task, this method reduces operator intervention in the process. The algorithm was first tested using geometric data generated in MATLAB and then through a set of data points acquired by measuring with a coordinate measuring machine and a 3D scan on real physical surfaces. Comparison time spent in measuring is presented to show the advantage of the method. The results validated the suitability and potential of the algorithm hereby proposed
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The Bananal Island is regarded the largest fluvial island in the world, bounded by Araguaia and Javaés rivers, being located in southwest of Tocantins. The objectives of this work were to provide information about the vegetational changes that occurred at the Bananal Island, in order to contribute to the understanding the dynamics of past and current savanna and areas of ecotones with forests. Thus, a sedimentary core collected from a small lake at the Bananal Island plain was submitted to pollen and radiocarbon dating analyses. The results showed that the last millennium was dominated by forest reflecting a wet climate. At the beginning of the record (920-770 yr cal BP) the wet climate and high rainfall produced flooding during long rainy seasons that maintained the Javaés River connected to the studied lake, and hence, this environment was marked by the presence of a homogenous forest rich in Moraceae/Urticaceae, due to flooded soils occurrence. During the following period (770-304 yr cal BP) the reduced rainfall and shortening of the rainy seasons isolated the lake from the Javaés River for long periods, which caused a diversification of the forest and gave rise to the appearance of the components of floodplain forest and marsh vegetation adapted to waterlogged soils. Since 304 years cal BP to the present day this environment remained dominated by this diverse forest and the lacustrine conditions were also similar to previous phase, with a slight increase of moisture in the last 84 years that caused the increase of Piranhea.
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Tese de Doutoramento em Estudos da Criana - Especialidade Comunicao Visual e Expresso Plstica
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OBJETIVO: Avaliar retrospectivamente, implante de stent (IS) em paciente com doena arterial coronria (DAC), realizado em 7 hospitais do Rio de Janeiro. MTODOS: De junho/94 a dezembro/96, foram realizados 2.220 procedimentos, e desses, analisados 783 IS em 660 (29,7%) pacientes, atravs da coronariografia sem subtrao digital. Os diversos tipos de stent, mais freqentemente, usados foram: Palmaz-Schatz (40,9%), Gianturco-Roubin (29,1%) e NIR (22,0%). As indicaes para o IS foram: leso de novo, 67,9%; leso reestentica, 16,0%; leso com resultado subtimo da angioplastia transluminal coronria (ATC), 8,2%; ocluso aguda ou provvel ps-ATC, 4,9%; ocluso crnica, 3,0%. Todos os stents foram implantados com alta presso, sem controle pelo ultra-som intracoronrio. A preveno da trombose subaguda, na maioria dos pacientes (87,8%), foi feita com o uso de ticlopidina e cido acetil-saliclico. RESULTADOS: Evoluo imediata: a) sucesso no IS em 770 leses: 98,0% em 646 (97,9%) pacientes; b) sucesso clnico em 634 (96,0%) casos; c) complicaes maiores: infarto agudo do miocrdio (IAM) - 1,1%; cirurgia de revascularizao miocrdica (CRM) - 1,4% e bito - 0,8%; d) complicaes vasculares com correo cirrgica e/ou sangramento - 3,0%. Evoluo tardia: a) dos 399 (60,4%) pacientes acompanhados clinicamente, a coronariografia de 121 (30,3%) mostrou retorno da leso no IS em 79 (19,8%) casos; b) freqncia de outros eventos: IAM - 1,5%; CRM - 2,3%; bito -1,0% e outra ATC ou procedimento similar - 12,5%. CONCLUSO: O estudo multicntrico mostrou que o IS na DAC pode ser realizado com segurana, alto ndice de sucesso imediato, poucas complicaes e baixa taxa de eventos cardacos na evoluo tardia.
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La carte postale est un kalidoscope de vues, dornements et de couleurs, qui consacre un tout petit espace au message. Cest la photographie et aux procds de reproduction photomcaniques que revient le mrite davoir industrialis la production de la carte postale. Et ce sont les clichs de villes, avec leurs monuments et leurs paysages, qui confrent la carte postale son statut de moyen de communication de masse et qui lui concdent une affinit avec lindustrie du tourisme. La carte postale sest ainsi empare de lambition photographique de reproduire le monde, salliant aux besoins de lexploration, des expditions et des relevs topographiques du mdium photographique ses dbuts. Ayant comme point de dpart la carte postale, notre objectif est de montrer les consquences culturelles de la rvolution optique, commence au milieu du XIXe sicle, avec linvention de lappareil photo, et consume dans la seconde moiti du XXe sicle, avec lapparition de lordinateur. En effet, depuis lapparition de lappareil photographique et des cartes postales jusquau flux de pixels de Google Images et aux images satellite de Google Earth, un entrelacement de territoire, puissance et technique a t mis en oeuvre, la terre devenant, en consquence, de plus en plus ausculte par les appareils de vision, ce qui impacte sur la perception de lespace. Nous esprons pouvoir montrer avec cette tude que la lettre traditionnelle est lemail ce que la carte postale est au post que lon publie dans un blog ou dans des rseaux comme Facebook et Twitter. notre sens, les cartes postales correspondent louverture maximale du systme postal moderne, qui duniversel devient dpendant et partie intgrante des rseaux tlmatiques denvoi. Par elles sont annoncs, en effet, la vitesse de transmission de linformation, la brivet de la parole et lhgmonie de la dimension imagtique du message, et pour finir, lembarras provoqu par la fusion de lespace public avec lespace priv.
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OBJETIVO: Avaliar, atravs da evoluo dos novos marcadores bioqumicos de injria cardaca, se a cardioverso eltrica (CVE) causa leso miocrdica. MTODOS: Foram avaliados 76 pacientes (P) submetidos a CVE eletiva de fibrilao atrial ou flutter atrial. Medidas de creatinafosfoquinase (CPK), CKMB-atividade e dosagem de CKMB-massa (M), mioglobina e troponina I cardaca (cTnI) foram determinadas antes e aps 6 e 24 horas da CVE. RESULTADOS: A CVE resultou um sucesso em 58 P (76,3%). A carga cumulativa (CC) foi de at 350 joules (J) em 36 P, de 500 a 650 J em 20 P e de 900 a 960 J em 20 P, com energia mdia aplicada de 493 J ( 309). A cTnI permaneceu dentro da normalidade nos 76 P. Com o aumento da CC, ocorreu elevao de CPK (> valor de p = 0,007), CKMB-atividade (> valor de p = 0,002), CKMB-M (> valor de p = 0,03) e mioglobina (> valor de p = 0,015). Correlao positiva foi observada entre a CC e picos de CPK (r = 0,660; p < 0,001), CKMB-atividade (r = 0,429; p < 0,0001), CKMB-M (r = 0,265; p = 0,02) e mioglobina (r = 0,684; p < 0,0001). Correlao tambm positiva ocorreu entre o nmero de choques e picos de CPK (r = 0,770; p < 0,001), CKMB-atividade (r = 0,642; p < 0,0001), CKMB-M (r = 0,430; p < 0,0001) e mioglobina (r = 0,745; p < 0,0001). CONCLUSO: A CVE no causa leso miocrdica detectvel pela dosagem da cTnI. Elevaes de CPK, CKMB-atividade, CKMB-M e mioglobina so decorrentes de leso do msculo esqueltico, estando correlacionadas positivamente com a CC aplicada ou com o nmero de choques.
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Background:Statins have proven efficacy in the reduction of cardiovascular events, but the financial impact of its widespread use can be substantial.Objective:To conduct a cost-effectiveness analysis of three statin dosing schemes in the Brazilian Unified National Health System (SUS) perspective.Methods:We developed a Markov model to evaluate the incremental cost-effectiveness ratios (ICERs) of low, intermediate and high intensity dose regimens in secondary and four primary scenarios (5%, 10%, 15% and 20% ten-year risk) of prevention of cardiovascular events. Regimens with expected low-density lipoprotein cholesterol reduction below 30% (e.g. simvastatin 10mg) were considered as low dose; between 30-40%, (atorvastatin 10mg, simvastatin 40mg), intermediate dose; and above 40% (atorvastatin 20-80mg, rosuvastatin 20mg), high-dose statins. Effectiveness data were obtained from a systematic review with 136,000 patients. National data were used to estimate utilities and costs (expressed as International Dollars - Int$). A willingness-to-pay (WTP) threshold equal to the Brazilian gross domestic product per capita (circa Int$11,770) was applied.Results:Low dose was dominated by extension in the primary prevention scenarios. In the five scenarios, the ICER of intermediate dose was below Int$10,000 per QALY. The ICER of the high versus intermediate dose comparison was above Int$27,000 per QALY in all scenarios. In the cost-effectiveness acceptability curves, intermediate dose had a probability above 50% of being cost-effective with ICERs between Int$ 9,000-20,000 per QALY in all scenarios.Conclusions:Considering a reasonable WTP threshold, intermediate dose statin therapy is economically attractive, and should be a priority intervention in prevention of cardiovascular events in Brazil.
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1) It may seem rather strange that, in spite of the efforts of a considerable number of scientists, the problem of the origin of indian corn or maize still has remained an open question. There are no fossil remains or archaeological relics except those which are quite identical with types still existing. (Fig. 1). The main difficulty in finding the wild ancestor- which may still exist - results from the fact that it has been somewhat difficult to decide what it should be like and also where to look for it. 2) There is no need to discuss the literature since an excellent review has recently been published by MANGELSDORF and REEVES (1939). It may be sufficient to state that there are basically two hypotheses, that of ST. HILAIRE (1829) who considered Brazilian pod corn as the nearest relative of wild corn still existing, and that of ASCHERSON (1875) who considered Euchlaena from Central America as the wild ancestor of corn. Later hypotheses represent or variants of these two hypotheses or of other concepts, howewer generally with neither disproving their predecessors nor showing why the new hypotheses were better than the older ones. Since nearly all possible combinations of ideas have thus been put forward, it har- dly seems possible to find something theoretically new, while it is essential first to produce new facts. 3) The studies about the origin of maize received a new impulse from MANGELSDORF and REEVES'S experimental work on both Zea-Tripsacum and Zea-Euchlaena hybrids. Independently I started experiments in 1937 with the hope that new results might be obtained when using South American material. Having lost priority in some respects I decided to withold publication untill now, when I can put forward more concise ideas about the origin of maize, based on a new experimental reconstruction of the "wild type". 4) The two main aspects of MANGELSDORF and REEVES hypothesis are discussed. We agree with the authors that ST. HILAIRE's theory is probably correct in so far as the tunicata gene is a wild type relic gene, but cannot accept the reconstruction of wild corn as a homozygous pod corn with a hermaphroditic tassel. As shown experimentally (Fig. 2-3) these tassels have their central spike transformed into a terminal, many rowed ear with a flexible rachis, while possessing at the same time the lateral ear. Thus no explanation is given of the origin of the corn ear, which is the main feature of cultivated corn (BRIEGER, 1943). The second part of the hypothesis referring to the origin of Euchlaena from corn, inverting thus ASCHERSON's theory, cannot be accepted for several reasons, stated in some detail. The data at hand justify only the conclusion that both genera, Euchlaena and Zea, are related, and there is as little proof for considering the former as ancestor of the latter as there is for the new inverse theory. 5) The analysis of indigenous corn, which will be published in detail by BRIEGER and CUTLER, showed several very primitive characters, but no type was found which was in all characters sufficiently primitive. A genetical analysis of Paulista Pod Corn showed that it contains the same gene as other tunicates, in the IV chromosome, the segregation being complicated by a new gametophyte factor Ga3. The full results of this analysis shall be published elsewhere. (BRIEGER). Selection experiments with Paulista Pod Corn showed that no approximation to a wild ancestor may be obtained when limiting the studies to pure corn. Thus it seemed necessary to substitute "domesticated" by "wild type" modifiers, and the only means for achieving this substitution are hybridizations with Euchlaena. These hybrids have now been analysed init fourth generation, including backcrosses, and, again, the full data will be published elsewhere, by BRIEGER and ADDISON. In one present publication three forms obtained will be described only, which represent an approximation to wild type corn. 6) Before entering howewer into detail, some arguments against ST. HILAIRE's theory must be mentioned. The premendelian argument, referring to the instability of this character, is explained by the fact that all fertile pod corn plants are heterozygous for the dominant Tu factor. But the sterility of the homozygous TuTu, which phenotypically cannot be identified, is still unexplained. The most important argument against the acceptance of the Tunicata faetor as wild type relic gene was removed recently by CUTLER (not yet published) who showed that this type has been preserved for centuries by the Bolivian indians as a mystical "medicine". 7) The main botanical requirements for transforming the corn ear into a wild type structure are stated, and alternative solutions given. One series of these characters are found in Tripsacum and Euchlaena : 2 rows on opposite sides of the rachis, protection of the grains by scales, fragility of the rachis. There remains the other alternative : 4 rows, possibly forming double rows of female and male spikelets, protection of kernels by their glumes, separation of grains at their base from the cob which is thin and flexible. 8) Three successive stages in the reconstruction of wild corn, obtained experimentally, are discussed and illustrated, all characterized by the presence of the Tu gene. a) The structure of the Fl hybrids has already been described in 1943. The main features of the Tunicata hybrids (Fig. -8), when compared with non-tunicate hybrids (Fig. 5-6), consist in the absence of scaly protections, the fragility of the rachis and finally the differentiation of the double rows into one male and one female spikelet. As has been pointed out, these characters represent new phenotypic effects of the tunicate factor which do not appear in the presence of pure maize modifiers. b) The next step was observed among the first backcross to teosinte (Fig. 9). As shown in the photography, Fig. 9D, the features are essencially those of the Fl plants, except that the rachis is more teosinte like, with longer internodes, irregular four-row-arrangement and a complete fragility on the nodes. c) In the next generation a completely new type appeared (Fig. 10) which resembles neither corn nor teosinte, mainly in consequence of one character: the rachis is thin and flexible and not fragile, while the grains have an abscission layer at the base, The medium sized, pointed, brownish and hard granis are protected by their well developed corneous glumes. This last form may not yet be the nearest approach to a wild grass, and I shall try in further experiments to introduce other changes such as an increase of fertile flowers per spikelet, the reduction of difference between terminal and lateral inflorescences, etc.. But the nature of the atavistic reversion is alveadwy such that it alters considerably our expectation when looking for a still existing wild ancestor of corn. 9) The next step in our deductions must now consist in an reversion of our question. We must now explain how we may obtain domesticated corn, starting from a hypothetical wild plant, similar to type c. Of the several changes which must have been necessary to attract the attention of the Indians, the following two seem to me the most important: the disappearance of all abscission layers and the reduction of the glumes. This may have been brought about by an accumulation of mutations. But it seems much more probable to assume that some crossing with a tripsacoid grass or even with Tripsacum australe may have been responsible. In such a cross, the two types of abscission layer would be counterbalanced as shown by the Flhybrids of corn, Tripsacum and Euchlaena. Furthermore in later generations a.tu-allele of Tripsacum may become homozygous and substitute the wild tunicate factor of corn. The hypothesis of a hybrid origin of cultivated corn is not completely new, but has been discussed already by HARSHBERGER and COLLINS. Our hypothesis differs from that of MANGELSDORF and REEVES who assume that crosses with Tripsacum are responsible only for some features of Central and North American corn. 10) The following arguments give indirects evidence in support of our hypothesis: a) Several characters have been observed in indigenous corn from the central region of South America, which may be interpreted as "tripsacoid". b) Equally "zeoid" characters seem to be present in Tripsacum australe of central South-America. c) A system of unbalanced factors, combined by the in-tergeneric cross, may be responsible for the sterility of the wild type tunicata factor when homozygous, a result of the action of modifiers, brought in from Tripsacum together with the tuallele. d) The hybrid theory may explain satisfactorily the presence of so many lethals and semilethals, responsible for the phenomenon of inbreeding in cultivated corn. It must be emphasized that corn does not possess any efficient mechanism to prevent crossing and which could explain the accumulation of these mutants during the evolutionary process. Teosinte which'has about the same mechanism of sexual reproduction has not accumulated such genes, nor self-sterile plants in spite of their pronounced preference for crossing. 11) The second most important step in domestication must have consisted in transforming a four rowed ear into an ear with many rows. The fusion theory, recently revived byLANGHAM is rejected. What happened evidently, just as in succulent pXants (Cactus) or in cones os Gymnosperms, is that there has been a change in phyllotaxy and a symmetry of longitudinal rows superimposed on the original spiral arrangement. 12) The geographical distribution of indigenous corn in South America has been discussed. So far, we may distinguish three zones. The most primitive corn appears in the central lowlands of what I call the Central Triangle of South America: east of the Andies, south of the Amazone-Basin, Northwest of a line formed by the rivers So Prancisco-Paran and including the Paraguay-Basin. The uniformity of the types found in this extremely large zone is astonishing (BRIEGER and CUTLER). To the west, there is the well known Andian region, characterized by a large number of extremely diverse types from small pop corn to large Cuszco, from soft starch to modified sweet corn, from large cylindrical ears to small round ears, etc.. The third region extends along the atlantic coast in the east, from the Caribean Sea to the Argentine, and is characterized by Cateto, an orange hard flint corn. The Andean types must have been obtained very early, and undoubtedly are the result of the intense Inca agriculture. The Cateto type may be obtained easily by crosses, for instance, of "So Paulo Pointed Pop" to some orange soft corn of the central region. The relation of these three South American zones to Central and North America are not discussed, and it seems essential first to study the intermediate region of Ecuador, Colombia and Venezuela. The geograprical distribution of chromosome knobs is rapidly discussed; but it seems that no conclusions can be drawn before a large number of Tripsacum species has been analysed.
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[s.c.]
