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Finalizado II CONCURSO INVESTIGACIÓN TECNOLÓGICA PROGRAMA IDEA FONDEF FONDEF

In underground works, the continual consciousness of geological and geomechanical properties of rock mass during drilling, is of major importance to optimize the works and the equipment used. In this paper, the mathematical relationship obtained from tunnel excavations, considering percussion drilling for blasting by a drilling machine and by a tunnel boring machine (TBM) are exposed. These mathematical relationships are useful in the percussion drilling case, to adjust the drilling parameter recorder (DPR) tools, and in the case of TBM to predict the rock mass geomechanical index (RMR). Taking into account the complexity of these mathematical models obtained, as a consequence of the affected variables and their relations, a fuzzy logic model based on parameters accessible to the drilling machine has been used in tricone bit drilling. Matematinis ir neraiškiosios logikos modeliai aprašant geologines ir geomechanines uolienos savybes, naudojant požeminio kasinėjimo duomenis Santrauka.Atliekant požeminius uolienų gręžimo darbus ir optimizuojant darbus bei jiems naudojamą įrangą, labai svarbu prognozuoti geologines ir geomechanines uolienos savybes. Šiame darbe pateikiamos gautos matematinės išraiškos, taikant tunelių kasimo duomenis, gautus naudojant smūginio gręžimo ir tunelių gręžimo (TBM) įrangą. Šios matematinės išraiškos yra naudingos smūginio gręžimo metu koreguojant gręžimo parametro fiksavimo (DPR) duomenis, o naudojant TBM įrangą – nustatant uolienos geomechaninį indeksą (RMR). Atsižvelgiant į gautų matematinių modelių kompleksiškumą, t. y. į gautus parametrus ir jų sąryšius, naudotinas neraiškiosios logikos modelis, jungiantis parametrus, tinkamus trigalvio grąžto gręžimo įrangai. Reikšminiai žodžiai:neraiškioji logika,tunelių gręžimo įranga,gręžimo parametro fiksavimas,trigalvis grąžtas.

La capacidad de simbolización es un proceso evolutivo con diferentes etapas. La elaboración de un método psicobiológico de análisis y de un modelo interpretativo permite determinar los marcadores arqueológicos de este proceso y ordenarlos en el tiempo y en el espacio. Así, proponemos un desarrollo en fases a lo largo del Paleolítico europeo, con grandes diferencias regionales, hasta la extensión continental del modelo en su más alto grado durante el Gravetiense, con la aparición de los comportamientos religiosos generalizados. The human capacity of symbolization is an evolutionary process with different stages. The production of both a psychobiological method of analysis and an interpretive model allows determining the archaeological markers of this process as well as arranging them in the time and in the space. Thus, we propose a phased development over the European Palaeolithic, with broad regional differences, reaching the continental extension of the model at its higher degree during the Gravettian, with the appearance of widespread religious behaviours.

Se estudio el efecto del peso vivo al sacrificio y del sexo sobre las características de la canal del cordero lactante del cruce Suffolk Down x Merino Precoz Alemán. Las variables cuantificadas fueron: peso canal caliente (PCC), longitud de la canal (LC), rendimiento comercial (RC) y verdadero (RV), área del Longissimus dorsi (ALD), espesor de grasa dorsal (EGD), peso de componentes corporales (PCCO), y rendimiento al trozado comercial (RTC). Se utilizaron 30 corderos (15 machos y 15 hembras) sacrificados a 2 pesos vivos: 10 kg (7 machos y 7 hembras) y 15 kg (8 machos y 8 hembras). Los resultados se analizaron considerando los dos pesos de sacrificio (10 y 15 kg), sexo y la interacción entre ellos. El PCC, LC, ALD y EGD fueron superiores en los animales sacrificados a los 15 kg (P0,05). Considerando los resultados obtenidos se puede afirmar que el cruce Suffolk Down x Merino Precoz Alemán, sacrificado a un peso vivo de 10 y 15 kg, presenta excelentes características para la producción de carne. The carcasses of thirty suckling lambs (Suffolk Down x German Merino Precocius) were studied to estimate the effect of sex and slaughter weight on: hot carcass weight, carcass length, commercial and true dressing percentages, ribeye area, dorsal fat thickness, body components weight, and retail yield. The results were analysed considering two slaughter weights (10 and 15 kg), sex, and their interaction. Hot carcass weight, carcass length, ribeye area, and dorsal fat thickness were affected by slaughter weight. Leg, shoulder, and chops. Showed the highest commercial yields and were not affected by sex, slaughter weight. nor their interaction. Based on these results it can be said that this genotype has excellent qualities for meat production. 621 - 626 Bimestral

Rares sont les ouvrages qui vous mènent dans le labyrinthe historique des relations entre deux pays sans jamais vous lâcher dans les ténèbres de la confusion. Pari réussi de l’auteur dans cet ouvrage consacré aux riches et ambiguës relations entretenues entre le Mexique et les Etats-Unis depuis le début du XIXe siècle, et qui semblent se perpétuer, sous d’autres aspects, encore aujourd’hui. Le parti pris d’une présentation chronologique de l’histoire peut surprendre, mais elle s’avère, grâce ...

Ce n’est que très récemment que les Etats-Unis, pays d’immigration par excellence, ont été confrontés à l’arrivée massive de populations en provenance du continent américain. Les lois d’immigration votées par le Congrès, respectivement en 1921 et 1924 étaient un choix délibéré des Etats-Unis dans son désir de maintenir et protéger l’homogénéité raciale et ethnique de la nation. Elles fermaient les portes du pays aux immigrants européens sans jamais les avoir ouvertes aux populations d’Amériqu...

Se presentan los resultados de una prospección intensiva del área de Wadi Soba-el-Hasib al este de Jartum en la orilla oriental del Nilo Azul y una exploración del Nilo Azul aguas arriba hasta Singa. El objetivo principal fueron losrestos prehistóricos, con un 80% de yacimientos mesolíticos (EarlyKhartoum), siendo el resto neolítico(Shaheinab-Jebel Moya) junto a escasos restos paleolíticos. Porprimera vez se han registrado yacimientosimportantes del Neolítico Final en el Sudán Central, siempreen áreas lejanas al Nilo de la Butana y laGezira. Se han aplicado métodos estadísticos multivariantes a los procesos de formación, seriación cerámica ymodelos de asentamiento. Se advierte elpaso primero de una explotación acuática por grupos móviles a unaconcentración demográfica decazadores-pastores de sabana, que luego adoptan una economía móvil contúmulos funerarios comoúnico resto arqueológico hasta la época moderna. The results are presented of an intensive survey of the Wadi Soba-el-Hasib area east of Khartoum on the east bank of the Blue Nile and the exploration of the Blue Nile Basin upstream to Singa. The survey focused mainly on the Prehistoric sites, with the Mesolithic period (Early Khartoum) as the mostly represented with more than 80% of the discovered sites, the Neolithic sites (Shaheinab-Jebel Moya) making up most of the remainder 20%. Very few Palaeolithic sites were recorded. Late Neolithic sites of large size have been found for the first time in the Central Sudan, all of them located away from the Blue Nile in the Butana and Gezira plains. Site structure and formation processes, ceramic seriation and settlement patterns have been analysed applying statistical multivariate methods to the survey quantitative data. Some historical trends have been noticed. The first is the change from a Nilewadi aquatic exploitation by small mobile groups towards demographic concentration of near-sedentary savanna hunting herding populations. During the Late Neolithic period the groups adopted a mobile economy and their only archaeological record thereafter are the burial tumuli fields up to the Christian and Islamic periods.

Resultados de las excavaciones en dos yacimientos mesolíticos, uno de la zona del río (Sheikh Mustafa- 1, fechado por carbono-14 en c. 7705-7600 bp) y otro en Wadi Soba (El Mahalab, c. 7705-6940 bp), y un yacimiento neolítico inicial del wadi (Sheikh el Amin, c. 5555-4590 bp), con análisis exhaustivos de estratigrafías, cerámicas, materiales líticos y otros hallazgos, usando métodos multivariantes (componentes principales, análisis factorial). Aunque la erosión ha afectado parcialmente a los sitios mesolíticos, se recuperaron importantes datos sobre la evolución cultural regional del VIII al V milenio bp, cuyas líneas de cambio van desde cerámicas nilóticas con líneas onduladas incisas a tipos saharianos on impresiones de líneas rectas y punteadas, y desde puntas de dorso y segmentos strechos a segmentos nchos que reflejan el paso de la pesca y caza mayor a la caza menor. La pesca pierde mportancia rogresivamente a lo largo del periodo de los tres yacimientos, mientras que la recolección vegetal, inferible a partir de los morteros, aumenta continuadamente para empezar a decrecer al final antes del paso a una economía pastoril nómada. Extensive excavations were carried out in two Mesolithic sites, in the river area (Sheikh Mustafa-1, radiocarbon dated to c. 7930-7600 bp) and in the Wadi Soba zone (El Mahalab, c. 7705-6940 bp), and at a wadi Early Neolithic site (Sheikh el Amin, c. 5555-4590 bp). The results of comprehensive analysis of stratigraphical conditions, pottery and lithic material and other cultural types are presented. Multivariate methods such as principal component and rotated factor analysis have been applied to quantitative data from excavated sectors and squares at the three sites. Even though the Mesolithic sites are partially deflated, significant information was gathered on the cultural evolution in the area during the 8th – 5th millennia bp. The inferred scenario presents several change trends: from specifically Nilotic pottery decoration (incised wavy line) to Saharan types such as impressed rocker and dotted wavy line, from lithic backed points and narrow lunates, used for fishing and hunting big game, to wide lunates for the hunting of smaller game. Fishing importance decreased along the whole period of the three sites. Plant gathering, deduced from grinders frequency, increased to a maximum during the Neolithic but a decrease is inferable for the latter phases of this period when the transition begun to a pastoralist way of life.

Significance The microbiome plays key roles in human health, but little is known about its evolution. We investigate the evolutionary history of the African hominid oral microbiome by analyzing dental biofilms of humans and Neanderthals spanning the past 100,000 years and comparing them with those of chimpanzees, gorillas, and howler monkeys. We identify 10 core bacterial genera that have been maintained within the human lineage and play key biofilm structural roles. However, many remain understudied and unnamed. We find major taxonomic and functional differences between the oral microbiomes of Homo and chimpanzees but a high degree of similarity between Neanderthals and modern humans, including an apparent Homo-specific acquisition of starch digestion capability in oral streptococci, suggesting microbial coadaptation with host diet., The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine–platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo-specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease.