479 research outputs found
Manufacturing and Validation of a Novel Composite Component for Aircraft Main Landing Gear Bay
Composite materials may reduce the final weight of the aircraft structural components, in addition to
improve fatigue performance and corrosion resistance. In order to achieve the optimization of air transport
systems, making them increasingly sustainable, the structural design must be surely reviewed, starting to
follow the ââcomposite thinkingââ philosophy. The present research provides some relevant outcomes concerning
the design of a composite sample for the main landing gear bay of a large commercial airplane
(EASA CS25 category), within ITEMB (integrated full composite main landing gear bay concept) project, a
program of Clean Sky 2 EU research framework. The most ambitious goal is to develop a new generation of
lower center fuselage (LCF) with an innovative integrated landing system in the fuselage, which is considered
the next frontier in the development of landing systems for medium-haul aircraft, such as the
Airbus A320 aircraft family. The development of a different architecture, with the landing gear integrated
within the related fuselage bay, could lead to a simplification of the whole subassembly with potential
advantage in terms of construction and assembly times. Final target of the project is the manufacturing of
an innovative monolithic composite structure that will replace the actual configuration (a mixed structure of
metal and composite subassemblies) reducing or actually removing all the cost of assembly and increasing
the production rate. This paper presents the main results of the work, introducing the main processing steps
and prototype results; in the last part of the work, also some experimental tests on significant element are
introduced as the first assessment of the technology readiness level that has been achieved
Depositional age and exhumation of Tethyan Sedimentary rocks intruded by Oligo-Miocene granite
Abstract HKT-ISTP 2013
A
Glucose-6-phosphate dehydrogenase plays a crucial role in the protection from redox-stress induced apoptosis.
Glucose-6-phosphate dehydrogenase-deleted embryonic stem (ES) cells (G6pdD) proliferate in vitro without special requirements, but when challenged with oxidants fail to sustain glutathione disulphide reconversion to reduced glutathione (GSH), entering a condition of oxidative stress. Here, we investigate the signalling events downstream of GSH oxidation in G6pdD and wild-type (wt) ES cells. We found that G6pdD ES cells are very sensitive to oxidants, activating an apoptotic pathway at oxidant concentrations otherwise sublethal for wt ES cells. We show that the apoptotic pathway activated by low oxidant concentrations is accompanied by mitochondria dysfunction, and it is therefore blocked by the overexpression of Bcl-XL. Bcl-XL does not inhibit the decrease in cellular GSH and reactive oxygen species formation following oxidant treatment. We also found that oxidant treatment in ES cells is followed by the activation of the MEK/ extracellular signal-regulated kinase (ERK) pathway. InterestÂŹingly, ERK activation has opposite outcomes in G6pdD ES cells compared to wt, which has a proapoptotic function in the ïŹrst and a prosurvival function in the latter. We show that this phenomenon can be regulated by the cellular GSH level
Pelviureteral junction obstruction: correlation of renal cell apoptosis and differential renal function
Childhood TherapyâRelated Acute Myeloid Leukemia with t(16;21)(q24;q22)/RUNX1-CBFA2T3 After a Primitive Neuroectodermal Tumor of the Chest Wall
The Global Stratotype Section and Point (GSSP) of the Serravallian Stage (Middle Miocene)
The Global Stratotype Section and Point (GSSP) for the Base of the Serravallian Stage (Middle Miocene) is defined in the Ras il Pellegrin section located in the coastal cliffs along the Fomm Ir-Rih Bay on the west coast of Malta (35°54'50"N, 14°20'10"E). The GSSP is at the base of the Blue Clay Formation (i.e., top of the transitional bed of the uppermost Globigerina Limestone). This boundary between the Langhian and Serravallian stages coincides with the end of the major Mi-3b global cooling step in the oxygen isotopes and reflects a major increase in Antarctic ice volume, marking the end of the Middle Miocene climate transition and the Earth's transformation into an "Icehouse" climate state. The associated major glacio-eustatic sea-level drop corresponds with sequence boundary Ser1 of Hardenbol et al. (1998) and supposedly with the TB2.5 sequence boundary of Haq et al (1987). This event is slightly older than the last common and/or continuous occurrence of the calcareous nannofossil Sphenolithus heteromorphus, previously considered as guiding criterion for the boundary, and is projected to fall within the younger half of Chron C5ACn. The GSSP level is in full agreement with the definitions of the Langhian and Serravallian in their respective historical stratotype sections in northern Italy and has an astronomical age of 13.82 Ma
Ultimate strength
Concern for the ductile behaviour of ships and offshore structures and their structural components under ultimate conditions. Attention shall be given to the influence of fabrication imperfections and in-service damage and degradation on reserve strength
CPO and quantitative textural analyses within sheath folds
Acknowledgments This has been a multi-national collaboration from authors based in Europe, North America, Australia and India. Erasmus funding to GIA in 2018 enabled a visit to Catania leading to discussion and initiation of this project. The authors are grateful to Amarnath Dandapat for preparation of superpolished rock thin sections at the Department of Geology and Geophysics (IIT Kharagpur, India). Niloy Bhowmik is thanked for assistance with SEM-EBSD data generation in the Central Research Facility (IIT Kharagpur, India). E.F. thanks Sibio Carmelo for thin sections preparation at the University of Turin (Italy). Authors are grateful to ANSTO laboratory personnel for the preparation of specimens (funded proposals: P9835 with the title âSheath fold texture characterisationâ, principal scientist: E.F.; co-proposers: G.I.A. and V.L.; DB6749 with the title âTexture analysis of rocksâ, principal scientist: V.L.; co-proposer: E.F.; DB9606 with the title âA pilot experiment for texture characterisation in a sheath foldâ, principal scientist: E.F..; co-proposers: G.I.A. and V.L.). L.N. and R.G. report that this publication has been assigned the NRCan contribution number 20230109. Many thanks to Richard D. Law and an anonymous reviewer for their careful revision that substantially improved the original version of the manuscript. We also thanks Dr. T.K. Cawood from the Geological Survey of Canada for her useful comments on the drafted manuscript. The editorial handling by Fabrizio Agosta is greatly appreciated.Peer reviewedPublisher PD
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