Abstract This article analyses the influence of the classical Roman tradition on the thought of the philosopher and revolutionary Karl Marx. Starting with the texts of his youth, which are closer to the fields of history and philosophy, it then moves on to the fields of the critique of political economy and revolutionary strategy in his mature period. In all of them, a more than substantial presence of the Roman tradition can be appreciated, so that the analysis focuses on certain key categories and topics of his thought.

Resumen Este artículo analiza la influencia de la tradición romana clásica en el pensamiento del filósofo y revolucionario Karl Marx. Partiendo de sus textos de juventud, más cercanos a los ámbitos de la historia y la filosofía, se pasa después a los ámbitos de la crítica de la economía política y la estrategia revolucionaria de su época de madurez. En todas ellas pueda apreciarse una más que sustantiva presencia de la tradición romana, por lo que el análisis se detiene en determinadas categorías y temáticas clave de su pensamiento.

Rabdomiossarcoma é um tumor raro, com uma incidência anual de 4,3 casos por milhão de crianças. É o sarcoma de partes moles mais comum na infância, com uma idade média de 6 a 8 anos no momento do diagnóstico. Um menino de 4 anos apresentou-se com uma história de um crescimento rápido (1 mês) lesão nodular em carúncula de seu olho esquerdo. O exame biomicroscópico mostrou uma lesão vascularizada sólida nodular na prega semilunar. A lesão foi removida cirurgicamente com obtenção de bordas infiltradas com células tumorais, segunda cirurgia foi feita com bordas tumorais livres. O diagnóstico de rabdomiossarcoma embrionário, tipo botrióide, de diferenciação intermediária foi feita. O tratamento para a rabdomiossarcoma botrióide é basicamente cirúrgico com o uso combinado de poliquimioterapia adjuvante. Em pacientes adolescentes e adultos (e não em lactentes onde os distúrbios do crescimento ósseo pode ocorrer) radioterapia externa pode ser combinada com a quimioterapia. Rabdomiossarcomas da conjuntiva sem extensão orbital são raramente relatadas. Apresentamos um caso de uma criança com um tumor raro que tivemos uma alta suspeita de malignidade e diagnóstico precoce e tratamento e criança é livre de doença sistêmica 6 anos e meio depois. Nosso grupo de pesquisa acredita que a chave para esses tumores é o alto índice de suspeita e tratamento precoce.

Rhabdomyosarcoma is a rare tumor, with an annual incidence of 4.3 cases per million children. Even thought, it is the most common soft tissue sarcoma in childhood, with a mean age of 6 to 8 years at diagnosis. A 4 year-old boy presented with a history of a fast growing (1-month) nodular lesion in the caruncle of his left eye. Slit lamp examination showed a vascularized solid nodular lesion in the semilunar fold. The lesion was surgically removed obtaining infiltrated edges with tumoral cells. A second surgery was performed with free tumour edges. The diagnosis of embryonal rhabdomyosarcoma, botryoid type, of intermediate differentiation was made. The treatment for botryoid rhabdomyosarcoma is basically surgical with the combined use of adjuvant polychemotherapy. In adolescent or adult patients (not in infants where growth bone disturbances can occur) external beam radiotherapy can be combined with chemotherapy. Rhabdomyosarcomas of the conjunctiva without orbital extension are rarely reported. We presented a case of a child with a rare tumor which we had a high suspicion of malignancy and early diagnosis and treatment and child is free of systemic disease 6 and half years later. Our research group believes that the key in these tumors is the high index of suspicion and early treatment.

The petrographic, heavy mineral analyses and geochemical results from the Nama Group indicate a recycled upper crust composition characterized mainly by metamorphic and granitic and minor mafic rocks sources. Paleocurrent analyses of the chromian spinel bearing sandstones of the Nama Basin point to a volcanic island arc source located in the Damara Belt. Detrital zircon dating of the Nama Group display major peaks of Neoproterozoic and Mesoproterozoic ages suggesting a provenance from the Damara/Gariep Belts and their basements. Paleocurrents from the west and the dominance of Neoproterozoic-Cambrian detrital U-Pb zircon ages (76%) in the "Molasse" stage of the foreland evolution probably indicate exhumation of the felsic volcanic arc root which probably occurred after the time indicated by the younger zircon dated at 531 ±9 Ma. The petrographic and geochemical results from the Arroyo del Soldado Group indicate a recycled upper crust composition characterized by source diversity composed of granite-gneissic and mafic-metamorphic rocks. On average, Nd isotopes account for negative eNd values and T DM ages in a range of variation found elsewhere within SW Gondwana. Detrital U-Pb zircon dating indicate sources dominated by Paleoproterozoic (1.7-2.0-2.2 Ga) and subordinate Archaean ages (2.5-2.9-3.5 Ga). The scarcity of Mesoproterozoic and Neoproterozoic zircons and paleocurrent directions towards the east indicate that the Arroyo del Soldado Group was fed by detritus from the Río de la Plata Craton favouring a passive margin tectonic setting for their deposition. Deformation of the Arroyo del Soldado Group took place ca. 530 Ma, after strike-slip collision.

Los resultados de petrografía, análisis de minerales pesados y geoquímica del Grupo Nama se caracterizan por una composición similar a la corteza continental superior reciclada con fuentes principalmente metamórficas-graníticas y con un componente máfico subordinado. Paleocorrientes de areniscas que contienen spinelos cromíferos pertenecientes a la Cuenca Nama indican una fuente localizada en el cinturón Damara. Edades U-Pb de circones detríticos del Grupo Nama muestran que los picos más importantes son Neoproterozoicos y Mesoproterozoicos y sugieren una proveniencia de los cinturones Damara- Gariep y sus basamentos. Paleocorrientes desde el oeste en los sedimentos molasicos de la Cuenca Nama y edades U-Pb en circones detríticos correspondientes al Neoproterozoico-Cambriano (76%) indican probablemente una fuente proveniente de una raíz de arco volcánico de composición félsica exhumada luego de la edad indicada por el circón mas joven que es de 531 ±9 Ma. La petrografía y los resultados geoquímicos del Grupo Arroyo del Soldado indican una composición comparable a la corteza continental superior reciclada y se caracteriza por una diversidad de fuentes granítico-gnéisica y rocas maficas metamórficas. En promedio isótopos de Nd presentan valores negativos de eNd y edades T DM similares a las encontradas en el Gondwana. Edades U-Pb en circones detríticos indican fuentes principalmente Palaeoproterozoicas (1.7-2.0-2.2 Ga) y subordinadamente Arqueanas (2.5- 2.9-3.5 Ga). La escasez de circones detríticos Meso-Neoproterozoicos y paleocorrientes hacia el este indican que el Grupo Arroyo del Soldado fue alimentado con detritos del cratón del Río de la Plata favoreciendo un ambiente geotectónico de margen pasivo para su depositación. Deformación del Grupo Arroyo del Soldado ca. 530 Ma ocurrió luego de colisión tangencial con un terreno de afinidad Africana. Finalmente la evolución paleogeografica basada en el análisis de proveniencia de la Cuenca Nama y la Cuenca del Grupo Arroyo del Soldado sugiere que la amalgamación del los cratones Kalahari/Congo con el cratón del Río de la Plata y el terreno Cuchilla Dionisio Pelotas (Arachania) ocurrió probablemente por acrecíon tangencial relacionado a un componente de esfuerzos N-S en un periodo durante 530 a 495 Ma.

Las Ventanas Formation (FmLV), defined and mapped by Midot (1984), is composed by a thick, finingand thinning-upward sequence covering an area in excess of 120 km² of the southern Nico Perez Terrane, Uruguay (Fig. 1). The structure in its type area corresponds to an ample syncline (Cerro Las Ventanas Syncline) with an axis oriented S20W (Figs. 2, 7f). Las Ventanas Formation is here subdivided into the following members: La Rinconada Member, Quebrada de Viera Member and El Perdido Member (Figs. 2, 4-5). La Rinconada Member is made up of basic volcanics, mainly basalts, vulcanoclastic breccias and subordinate basic tuffs, reaching 500 m in thickness (Fig. 6). It is overlain with erosional unconformity by the Quebrada de Viera Member, which is composed by polymictic conglomerates, grading to conglomerate-sandstone intercalations up section (Fig. 7a-d). Maximum thickness reaches 3800 m. Lithoclast composition shows provenance from a mixed volcanic (basic and acid) and granitic source area (Fig. 8a-b). Whereas basalt clasts are more common at the base, rhyolitic clasts and intercalated rhyolitic tuffs occur at the top of the Quebrada de Viera Member (Fig. 5). The overlying El Perdido Member (600 m measured thickness) is characterized by laminated siltstones and shales (Figs. 7e-f, 9), showing reddish colours at the base and green and grey colours at the top. Abundant pyrite at the top of this Member indicates disoxic or anoxic conditions (Fig 7e-8d). Thus, Las Ventanas Formation represents a deepening-upward sequence, recording evolution from an alluvial fan-dominated environment to shallow marine conditions with occasional storms indicated by hummocky cross stratification at the top of Quebrada de Viera Member (Fig. 9). Petrography shows compositional and textural immaturity of conglomerates and sandstones which together with sedimentary structures point to a steep palaeorelief. Las Ventanas Formation is intruded by syenites of the Sierra de Animas Formation, which yielded a Rb- Sr age of 520 ± 5 Ma, and also by the Pan de Azúcar Granite (559 ± 28 Ma, Rb-Sr). K-Ar datings of 572 ± 7 Ma obtained for synkinematic muscovites crystallized along the Puntas del Pan de Azúcar Thrust, suggest a minimum Vendian age for the unit (Figs. 1-2). A number of organic-walled microfossils is described for the first time, namely: Leiosphaeridia tenuissima, Leiosphaeridia minutissima, Lophosphaeridium sp., Soldadophycus bossii, Soldadophycus major, Soldadophycus sp., Vendotaenia sp (Fig. 11). The assemblage is characterized by its low diversity, abundance and large size (up to 400 µm) of Leiosphaeridia. Wrinkle structures occur in the upper El Perdido Member (Fig. 9). Based on the microfossils and the available datings, we assign Las Ventanas Formation to the Ediacaran (lower Vendian, ca. 600 Ma). The Playa Hermosa Formation is in tectonic contact with Las Ventanas Formation, and can be interpreted as a lateral facies or -alternatively- be younger than the latter unit (Fig. 12). On the basis of their microfossil assemblages, we envisage that Las Ventanas Formation immediately predates the Arroyo del Soldado Group which represent a thick shelf succession deposited in the upper Ediacaran between 580 and 535 Ma. An extensional geotectonic setting, possibly a rift, is postulated for Las Ventanas Formation. In favour of this hypothesis argue the bimodal (rhyolitic and basaltic), synsedimentary volcanism, steep palaeorelief, great thickness of alluvial fan conglomerates with more than 3500 m of psephitic sediments and the evolution from continental to open marine environments. A number of magmatic units may be associated to this extensional event, including the Nico Pérez Dyke Swarm (581 ± 13 Ma) and the Puntas del Santa Lucía Batholith (633 ± 10 Ma).

Se analiza la estratigrafía, paleontología y edad de la Formación Las Ventanas (FmLV). El área tipo de afloramiento de la FmLV corresponde a un gran sinclinal (Sinclinal del Cerro Las Ventanas) con eje buzante al S20W. Se describe la litoestratigrafía para la FmLV separándola en los siguientes miembros (de base a tope): Miembro La Rinconada, Miembro Quebrada de Viera, y Miembro El Perdido. El Miembro La Rinconada se compone principalmente de coladas basálticas y brechas volcánicas. El Miembro Quebrada de Viera se caracteriza por potentes depósitos de conglomerados polimícticos y areniscas subordinadas. El tope de la FmLV (Miembro El Perdido) lo ocupan pelitas con laminación conspicua y mostrando evidencias de ambiente disóxicos en la cima. Por primera vez se correlacionan afloramientos en torno a la ciudad de Minas con la FmLV, mostrando una evolución de facies proximales a distales de sur a norte y de oeste a este. La formación representa una secuencia grano y estrato decreciente, evolucionando de un ambiente continental dominado por abanicos aluviales a un ambiente marino somero con la ocurrencia de tempestitas. La paleopendiente fue importante, como lo indican las estructuras sedimentarias y la petrografía de conglomerados y areniscas. Una asociación de microfósiles de pared orgánica ocurre en la FmLV, a saber: Leiosphaeridia tenuissima, L. minutissima, Lophosphaeridium sp., Soldadophycus bossii, S. major, Soldadophycus sp. y Vendotaenia sp. La asociación se destaca por su baja diversidad, abundancia de Leiosphaeridia y el gran tamaño de los esferomorfos (hasta 400 µm). Se describen asimismo estructuras de biomatas (wrinkle structures) del Miembro El Perdido. En base a los microfósiles se le asigna a la FmLV una edad más probable Ediacarense (Vendiano inferior, ca. 600 Ma). La Formación Playa Hermosa puede ser una facies lateral de la FmLV, o bien encontrarse estratigráficamente por encima de la misma. De acuerdo al contenido micropaleontológico de la FmLV, se postula una cercanía temporal con el Grupo Arroyo del Soldado, posiblemente anterior al mismo. El ambiente geotectónico más probable para la FmLV es extensional, y específicamente de rift. En favor de esta hipótesis se cita el vulcanismo bimodal sinsedimentario, las fuertes paleopendientes, importantes espesores de depósitos psefíticos y la evolución de ambientes continentales a marinos. Se asocian a este evento extensional el haz de diques máficos de Nico Pérez (581 ± 13 Ma) y el Batolito de Puntas del Santa Lucía (633 ± 10 Ma), indicando que el régimen tectónico imperante en el Terreno Nico Pérez entre 633 y 580 Ma fue claramente extensional.