424 research outputs found

    Mejora del olmo para resistencia a DED: clones italianos y características de su madera

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    In Italy, an elm breeding program to develop Dutch elm disease-resistant trees has been established by cross-breeding Asian elms with indigenous species, in order to produce individuals that combine resistance of the first with growth characteristics and higher degree of environmental adaptability of the second. Thus, the favourable adaptation of Ulmus pumila in Italy has been explored: «San Zanobi» and «Plinio» are two recent results of this research and many others promising clones as «FL090», «FL146», «FL441», «FL568», «FL634», are in the final stage of field testing. The resistance levels of all these clones were significantly higher level of resistance than «Lobel» and «Urban» in several assessments during different years. First technological tests indicate that the wood characteristics of «San Zanobi» and «FL090» clones are comparable to those of elm wood traditionally present on the market, thus highlighting that those clones is likely to satisfy the elm wood demand. The present characterisation needs to be confirmed by further evaluations of mature trees having bigger diameters and allowing industrial trials, still not available so far.En Italia, el programa de mejora genética del olmo para la obtención de árboles resistentes a la grafiosis se ha desarrollado a partir del cruzamiento de olmos asiáticos con especies nativas, y tiene por objetivo producir individuos que combinen la resistencia de los primeros con las características vegetativas y el alto grado de adaptación al ambiente de los segundos. Por esta razón, se ha aprovechado la favorable adaptación de Ulmus pumila en Italia: «San Zenobi» y «Plinio » son dos resultados recientes de estas investigaciones, y otros muchos clones prometedores como «FL090», «FL146», «FL441», «FL568» y «FL634» están en las fases finales de las pruebas de campo. Los niveles de resistencia de todos estos clones fueron significativamente mayores, en diferentes ensayos, que los niveles de resistencia de «Lobel» y «Urban ». Los primeros ensayos tecnológicos han mostrado que las características de la madera de los clones «San Zenobi» y «FL090» son comparables a los de las maderas de olmo tradicionalmente presentes en el mercado, indicando que esos clones pueden probablemente satisfacer las demandas de madera. La actual caracterización debe ser confirmada con nuevas evaluaciones en árboles maduros de mayores diámetros y mediante ensayos industriales aún no disponibles

    Who were the Nataruk people? Mandibular morphology among late Pleistocene and early Holocene fisher-forager populations of West Turkana (Kenya).

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    Africa is the birthplace of the species Homo sapiens, and Africans today are genetically more diverse than other populations of the world. However, the processes that underpinned the evolution of African populations remain largely obscure. Only a handful of late Pleistocene African fossils (∼50-12 Ka) are known, while the more numerous sites with human fossils of early Holocene age are patchily distributed. In particular, late Pleistocene and early Holocene human diversity in Eastern Africa remains little studied, precluding any analysis of the potential factors that shaped human diversity in the region, and more broadly throughout the continent. These periods include the Last Glacial Maximum (LGM), a moment of extreme aridity in Africa that caused the fragmentation of population ranges and localised extinctions, as well as the 'African Humid Period', a moment of abrupt climate change and enhanced connectivity throughout Africa. East Africa, with its range of environments, may have acted as a refugium during the LGM, and may have played a critical biogeographic role during the heterogene`ous environmental recovery that followed. This environmental context raises a number of questions about the relationships among early Holocene African populations, and about the role played by East Africa in shaping late hunter-gatherer biological diversity. Here, we describe eight mandibles from Nataruk, an early Holocene site (∼10 Ka) in West Turkana, offering the opportunity of exploring population diversity in Africa at the height of the 'African Humid Period'. We use 3D geometric morphometric techniques to analyze the phenotypic variation of a large mandibular sample. Our results show that (i) the Nataruk mandibles are most similar to other African hunter-fisher-gatherer populations, especially to the fossils from Lothagam, another West Turkana locality, and to other early Holocene fossils from the Central Rift Valley (Kenya); and (ii) a phylogenetic connection may have existed between these Eastern African populations and some Nile Valley and Maghrebian groups, who lived at a time when a Green Sahara may have allowed substantial contact, and potential gene flow, across a vast expanse of Northern and Eastern Africa

    Non-Destructive Inspection of High Temperature Piping Combining Ultrasound and Eddy Current Testing

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    Project Hi2TRUST—Second generation platform for high-temperature component inspection, (Ref. 3335), supported by Fundo Europeu de Desenvolvimento Regional (FEDER), Programa Operacional Regional de Lisboa (Lisb@2020 and Portugal2020). Publisher Copyright: © 2023 by the authors.This paper presents an automated Non-Destructive Testing (NDT) system for the in-service inspection of orbital welds on tubular components operating at temperatures as high as 200 °C. The combination of two different NDT methods and respective inspection systems is here proposed to cover the detection of all potential defective weld conditions. The proposed NDT system combines ultrasounds and Eddy current techniques with dedicated approaches for dealing with high temperature conditions. Phased array ultrasound was employed, searching for volumetric defects within the weld bead volume while Eddy currents were used to look for surface and sub-surface cracks. The results from the phased array ultrasound results showed the effectiveness of the cooling mechanisms and that temperature effects on sound attenuation can be easily compensated for up to 200 °C. The Eddy current results showed almost no influence when temperatures were raised up to 300 °C.publishersversionpublishe

    Mini-invasive robotic assisted pyelolithotomy: Comparison between the transperitoneal and retroperitoneal approach.

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    OBJECTIVE: To compare the retroperitoneal with the transperitoneal approach in a series of patients underwent to robotic-assisted pyelolithotomy (RP). MATERIALS AND METHODS: From January 2015 to December 2018 we evaluated 20 patients subjected to robotic pyelolithotomy; 11 patients were treated with retroperitoneal approach (RRP) and 9 with transperitoneal approach (TRP). For each patient intra and perioperative data were recorded: operative time (OT), blood loss (BL), length of hospital stay (LOS), stone clearance, post-operative complications and time to remove the drain. The presence of stone fragments < 4 mm was considered as stone free rate. RESULTS: The principal stone burden was greater in the TRP group than in the RRP group (48 ± 10 mm vs 32 ± 14 mm, p = 0.12). Preoperative hydronephrosis was present in 7 (64%) patients in RRP group and a mild hydronephrosis in 3 of TRP group (p = 0.04). The average operative time was higher in the RRP group than in the TRP group (203 ± 45 min vs 137 ± 31 min, p = 0.002). The average blood loss was 305 ± 175 ml in the RRP group versus 94 ± 104 ml in the TRP group (p = 0.005). The stone free rate was similar between the two groups, 36% (4 patients) in the RRP group and 44% (4 patients) in the TRP (p = 0.966). CONCLUSIONS: RP appears to be a safe and effective minimally invasive treatment for some patients with renal staghorn calculi or urinary tract malformations. The TRP may give lower operative time and better results in terms of blood loss and length of hospital stay
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