Notas sobre depósitos de Taveiro estratigrafia, paleontologia, idade, paleoecologia

This paper reports some research work that has been done to support Geological Survey's field work for the 1:50.000 Carta Geológica de Portugal, (sheets 19-C Figueira da Foz and 19-D Coimbra-Lousã). Its main purpose was to establish the age of some continental formations. At Cerâmica do Mondego, Ld.ª near Taveiro, two series were observed. The lower one is mainly pelitic, montmorillonite being predominant. It also includes some sandy beds and channel deposits with high energy sediments (conglomerate with limestone pebbles). The upper series lies unconformably upon the former, and there is a neat discontinuity surface between the two. It mainly consists of sands, kaolinite being the most abundant of the clay minerals. This seems to indicate an intensive weathering, an acid, well drained environment and transportation by quite high energy running waters. No fossils were recorded. Preliminary paleontological results are presented, along with some data concerning other localities (Aveiro, etc.). Fossils found in the lower series are: gastropoda (Bulimus gaudryi, TV. 15 bed), several vertebrates (TV. 18), fishes (TV. 19?) and plants (TV. 19-TV. 24). Vertebrata belong to the same fauna as that from Vizo, Aveiro, etc. The presence of mammals is most important as only a single tooth was previously Know in Europe (Southern France) in Late Cretaceous formations. Elsewhere there are some mammalian remains in Peru besides the rich assemblages found in the USA and Mongolia. Plants are representative of the «Debeya flora» well known at several localities in Beira Litoral province, in «Buçaco sandstones», and in Lisbon's «Basaltic Complex». The most important stratigraphical conclusion is that the lower series is Upper Campanian and/or Maastrichtian in age, and not Tertiary as sometimes it has been considered. As at Aveiro, «Bebeya flora» occurs in-beds somewhat higher than those with the Aveiro-Vizo-Taveiro vertebrate fauna. Correlation with other «Debeya flora» localities are now more clear. Data concerning Taveiro lower series, in the whole, point out to a rather warm (and moist?) environment in an occasionally (seasonally?) flooded region.

Notes sur la géologie et la paleontology du Miocène de Lisbonne; (XX) les plus anciens mastodontes tetralophodontes (Langhien inférieur Vb), évolution et remarques sur la tetralophodontie

This study deals with mastodont teeth found near Lisbon in Lower Langhian (lower Middle Miocene) fluviatile, feldspathic sands (Vb division). Conclusions are as follows: 1. Tetralophodont molars (even if at a still primitive stade of the tetralophodont condition) do exist at least since lower Langhian times, and not only since late Middle Miocene as was previously known. 2. Tri- and tetralophodont structures may (and indeed do) coexist in the same individual: such examples do not correspond to transitional forms, but instead to a mosaic of juxtaposed characters (however this does not mean there are no transitional forms in other instances). 3. So these structures coexisted in a population not yet geneticaliy separated beyond fertile cross-breeding, i.e. beyond species'level. 4. Origin of the tetralophodont molar was due to some mutation (s). but without crossing species, limits and even more genus' ones. 5. At this times probably soon after the first appearance of tetralophodont mutants, animals with such characters were a small but signifiant minority among the population (17% if account is taken on D4's: only 2% after M2's). 6. There was not then any direct and clear correlation between number of lophs (transversal crests) and tooth size, even if the increase of such number goes along with length's increase. 7. Dimensions (length in special) in tetralophodont teeth tend to exceed those in «normal» trilophodont teeth, this being particularly clear in D4, even if there is no clear distinction: the situation is quite the same, maybe less marked, with the M2. 8. According to the preceding conclusions there are no reasons to segregate different taxa among such mastodont population on the grounds of the presence in D4, M1 and M2 of 3 or 4 crests (this character being regarded as diagnostic of the genus Tetralophodon). 9. On the contrary, if any natural (in biological sense) classification is disregarded and a morphological parataxonomy is adopted there should be considered both Gomphotherium angustidens and Tetralophodon sp.: however this is absolutely not our opinion.

Notas sobre depósitos de Taveiro estratigrafia, paleontologia, idade, paleoecologia

This paper reports some research work that has been done to support Geological Survey's field work for the 1:50.000 Carta Geológica de Portugal, (sheets 19-C Figueira da Foz and 19-D Coimbra-Lousã). Its main purpose was to establish the age of some continental formations. At Cerâmica do Mondego, Lda. near Taveiro, two series were observed. The lower one is mainly pelitic, montmorillonite being predominant. It also includes some sandy beds and channel deposits with high energy sediments (conglomerate with limestone pebbles). The upper series lies unconformably upon the former, and there is a neat discontinuity surface between the two. It mainly consists of sands, kaolinite being the most abundant of the clay minerals. This seems to indicate an intensive weathering, an acid, well drained environment and transportation by quite high energy running waters. No fossils were recorded. Preliminary paleontological results are presented, along with some data concerning other localities (Aveiro, etc). Fossils found in the lower series are: gastropoda (Bulimus gaudryi, TV. 15 bed), several vertebrates (TV. 18), fishes (TV. 19?) and plants (TV. 19-TV. 24). Vertebrata belong to the same fauna as that from Vizo, Aveiro, etc. The presence of mammals is most important as only a single tooth was previously know in Europe (Southern France) in Late Cretaceous formations. Elsewhere there are some mammalian remains in Peru besides the rich assemblages found in the USA and Mongolia. Plants are representative of the «Debeya flora» well known at several localities in Beira Litoral province, in «Buçaco sandstones», and in Lisbon's «Basaltic Complex». The most important stratigraphical conclusion is that the lower series is Upper Campanian and/or Maastrichtian in age, and not Tertiary as sometimes it has been considered. As at Aveiro, «Bebeya flora» occurs in-beds somewhat higher than those with the Aveiro-Vizo-Taveiro vertebrate fauna. Correlation with other «Debeya flora» localities are now more clear. Data concerning Taveiro lower series, in the whole, point out to a rather warm (and moist?) environment in an occasionally (seasonally?) flooded region.

Paralophiodon cf. leptorhynchum (tapiroidea, mammalia) à Vale Furado: contribution à la connaissance de l’éocène au Portugal

A canine tooth from Vale Furado is classified as Paralophiodon cf. leptorhynchum. The genus Paralophiodon indicates an age from Lower Lutetian to Auversian, Middle Eocene. As it belongs in the lineage of P. leptorhynchum, possible age span is furth~L~uced from Middle Lutetian to Auversian. This conclusion remains valid or nearly so even in the less probable case of confusion with some form included in P. isselensis lineage. Our previous (1975) datation for sandstones and pelites from Vale Furado is thus confirmed, and more accurately recognized. Paralophiodon and the crocodilian Iberosuchus are a rather sound basis for correlation with stratigraphical units near Zamora and Salamanca in Spain.

Low-loss austempered ductile iron gears: experimental evaluation comparing materials and lubricants

An experimental study to evaluate the power dissipation of gears was performed. Three low-loss gear models were manufactured using standard 20° pressure angle tools. Austempered ductile iron (ADI) and 20MnCr5 carburized steel gears were tested in an FZG gear test machine using mineral, ester and polyalphaolephine (PAO)-based oils. The results compare power dissipation, the influence of different tooth flank geometries, materials and lubricants. This work concludes that conventional power-transmission gears can be replaced by these improved and more efficient low–loss models, which can be produced using common tools and that steel gears can be successfully replaced by austempered ductile iron gears.

Contextual and individual indicators associated with the presence of teeth in adults

OBJECTIVE The objective of this study was to analyze whether socioeconomic conditions and the period of availability of fluoridated water are associated with the number of teeth present.METHODSThis cross-sectional study analyzed data from 1,720 adults between 20 and 59 years of age who resided in Florianópolis, SC, Southern Brazil, in 2009. The outcome investigated was the self-reported number of teeth present. The individual independent variables included gender, age range, skin color, number of years of schooling, and per capita household income. The duration of residence was used as a control variable. The contextual exposures included the period of availability of fluoridated water to the households and the socioeconomic variable for the census tracts, which was created from factor analysis of the tract’s mean income, education level, and percentage of households with treated water. Multilevel logistic regression was performed and inter-level interactions were tested.RESULTS Residents in intermediate and poorer areas and those with fluoridated water available for less time exhibited the presence of fewer teeth compared with those in better socioeconomic conditions and who had fluoridated water available for a longer period (OR = 1.02; 95%CI 1.01;1.02). There was an association between the period of availability of fluoridated water, per capita household income and number of years of education. The proportion of individuals in the poorer and less-educated stratum, which had fewer teeth present, was higher in regions where fluoridated water had been available for less time.CONCLUSIONS Poor socioeconomic conditions and a shorter period of availability of fluoridated water were associated with the probability of having fewer teeth in adulthood. Public policies aimed at reducing socioeconomic inequalities and increasing access to health services such as fluoridation of the water supply may help to reduce tooth loss in the future.

Low torque loss gears: austempered ductile iron versus carburized steel

Low-loss power transmission gears operate at lower temperature than conventional ones because their teeth geometry is optimized to reduce friction. The main objective of this work is to compare the operating stabilization temperature and efficiency of low-loss austempered ductile iron (ADI) and carburized steel gears. Three different low-loss tooth geometries were adopted (types 311, 411 and 611, all produced using standard 20° pressure angle tools) and corresponding steel and ADI gears were tested in a FZG machine. The results obtained showed that low-loss geometries had a significant influence on power loss, gears 611 generating lower power loss than gears 311. At low speeds (500 and 1000 rpm) and high torque ADI gears generated lower power loss than steel gears. However, at high speed and high torque (high input power and high stabilization temperature) steel gears had better efficiency.

Color and Luminescence stability of selected dental materials in vitro

To study luminescence, reflectance, and color stability of dental composites and ceramics. Materials and Methods: IPS e.max, IPS Classic, Gradia, and Sinfony materials were tested, both unpolished (as-cast) and polished specimens. Coffee, tea, red wine, and distilled water (control) were used as staining drinks. Disk-shaped specimens were soaked in the staining drinks for up to 5 days. Color was measured by a colorimeter. Fluorescence was recorded using a spectrofluorometer, in the front-face geometry. Time-resolved fluorescence spectra were recorded using a laser nanosecond spectrofluorometer. Results: The exposure of the examined dental materials to staining drinks caused changes in color of the composites and ceramics, with the polished specimens exhibiting significantly lower color changes as compared to unpolished specimens. Composites exhibited lower color stability as compared to ceramic materials. Water also caused perceptible color changes in most materials. The materials tested demonstrated significantly different initial luminescence intensities. Upon exposure to staining drinks, luminescence became weaker by up to 40%, dependent on the drink and the material. Time-resolved luminescence spectra exhibited some red shift of the emission band at longer times, with the lifetimes in the range of tens of nanoseconds. Conclusions: Unpolished specimens with a more developed surface have lower color stability. Specimens stored in water develop some changes in their visual appearance. The presently proposed methods are effective in evaluating the luminescence of dental materials. Luminescence needs to be tested in addition to color, as the two characteristics are uncorrelated. It is important to further improve the color and luminescence stability of dental materials.

The bovid from the Carriça clay-pit (Côja): a discussion

A Bovid tooth referred to in the litterature as from the same locality that yielded upper Eocene mammals belongs to a modem or probably contemporary Bos taurus (domestic cattle); it is not a fossil and certainly was not found in situ. As it may induce in confusion, it must not anymore be taken into account in future paleontological and stratigraphic work.

Periodontal aspects of the juvenile form of paracoccidioidomycosis

Three cases of the juvenile form of paracoccidioidomycosis are reported. Emphasis has been given to the oral manifestations, particularly the periodontal involvement. The main periodontal findings were: generalized and progressive alveolar bone destruction leading to gingival recession with exposure of the tooth roots, and spontaneous tooth losses. The gingival mucosa was predominantly smooth, erithematous and slightly swollen. These aspects, although rare, may be the earliest signs of the disease and sometimes its only manifestation.

Manobras de condução assistida para veículos submarinos subactuados

A intervenção humana no manuseamento de veículos submarinos operados remotamente (ROVs) é um requisito necessário para garantir o sucesso da missão e a integridade do equipamento. Contudo, a sua teleoperação não é fácil, pelo que a condução assistida destes veículos torna-se relevante. Esta dissertação propõe uma solução para este problema para ROVs de 3DOF (surge, heave e yaw). São propostas duas abordagens distintas – numa primeira propõe-se um sistema de controlo Image Based Visual Servoing (IBVS) tendo em vista a utilização exclusiva de uma câmara (sensor existente neste tipo de sistemas) por forma a melhorar significativamente a teleoperação de um pequeno ROV; na segunda, propõe-se um sistema de controlo cinemático para o plano horizontal do veículo e um algoritmo de uma manobra capaz de dotar o ROV de movimento lateral através de uma trajectória dente-de-serra. Demonstrou-se em cenários de operação real que o sistema proposto na primeira abordagem permite ao operador de um ROV com 3DOF executar tarefas de alguma complexidade (estabilização) apenas através de comandos de alto nível, melhorando assim drasticamente a teleoperação e qualidade de inspecção do veículo em questão. Foi também desenvolvido um simulador do ROV em MATLAB para validação e avaliação das manobras, onde o sistema proposto na segunda abordagem foi validado com sucesso.

Envenomation by neotropical Opisthoglyphous colubrid Thamnodynastes cf. pallidus Linné, 1758 (Serpentes:Colubridae) in Venezuela

This is a case report of a "non-venomous" snake bite in a herpetologist observed at the Sciences Faculty of the Universidad de los Andes (Mérida, Venezuela). The patient was bitten on the middle finger of the left hand, and shows signs of pronounced local manifestations of envenomation such as bleeding from the tooth imprint, swelling and warmth. He was treated with local care, analgesics, and steroids. He was dismissed from the hospital and observed at home during five days with marked improvement of envenomation. The snake was brought to the medical consult and identified as a Thamnodynastes cf. pallidus specimen. This report represents the first T. pallidus accident described in a human.

Empirical models for quantification of machining damage in composite materials

Dissertação para obtenção do Grau de Doutor em Engenharia Mecânica

Multiple Mechanical Complications in ST-Segment Elevation Myocardial Infarction with Angiographically Normal Coronary Arteries

This case report discusses an unusual presentation of ST-segment elevation myocardial infarction (STEMI) with normal coronary arteries and severe mechanical complications successfully treated with surgery. An 82-year-old man presented STEMI with angiographically normal coronary arteries and no major echocardiographic alterations at discharge. At the first month follow-up, he complained of fatigue and dyspnea, and contrast echocardiography complemented by cardiac magnetic resonance imaging revealed a large left ventricular apical aneurysm with a thrombus communicating by two jets of a turbulent flow to an aneurysmatic formation of the right ventricular apex. The patient underwent a Dor procedure, which was successful. Ventricular septal defects and ventricular aneurysms are rare but devastating complications of STEMI, with almost all patients presenting multivessel coronary artery disease. Interestingly in this case, the angiographic pattern was normal.

Compact ion-source based on superionic rubidium silver iodide (RbAg4I5) solid electrolyte

Dissertação para obtenção do Grau de Mestre em Engenharia Física