521 research outputs found

    The Columbus logistics support at the APMC: Requirements and implementation aspects

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    This paper focuses on the logistics support to be provided by the APM Center (APMC). Among the Columbus ground infrastructures, this center is tasked to provide logistics, sustaining engineering and P/L integration support to the ongoing missions of the APM, i.e. the Columbus Laboratory attached to the Freedom Space Station. The following is illustrated: an analysis of the requirements that are levied on the logistics support of the APM; how such requirements are reflected in the corresponding support to be available on-ground and at APMC; the functional components of the APMC logistics support and how such components interact each other; how the logistics support function interfaces with the other functions of the ground support; and how the logistics support is being designed in terms of resources (such as hardware, data bases, etc.). Emphasis is given to the data handling aspects and to the related data bases that will constitute for the logistics activities the fundamental source of information during the APM planned lifetime. Functional and physical architectures, together with trades for possible implementation, are addressed. Commonalities with other centers are taken into account and recommendations are made for possible reuse of tools already developed in the C/D phase. Finally, programmatic considerations are discussed for the actual implementation of the center

    Hybrid photonic-bandgap accelerating cavities

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    In a recent investigation, we studied two-dimensional point-defected photonic bandgap cavities composed of dielectric rods arranged according to various representative periodic and aperiodic lattices, with special emphasis on possible applications to particle acceleration (along the longitudinal axis). In this paper, we present a new study aimed at highlighting the possible advantages of using hybrid structures based on the above dielectric configurations, but featuring metallic rods in the outermost regions, for the design of extremely-high quality factor, bandgap-based, accelerating resonators. In this framework, we consider diverse configurations, with different (periodic and aperiodic) lattice geometries, sizes, and dielectric/metal fractions. Moreover, we also explore possible improvements attainable via the use of superconducting plates to confine the electromagnetic field in the longitudinal direction. Results from our comparative studies, based on numerical full-wave simulations backed by experimental validations (at room and cryogenic temperatures) in the microwave region, identify the candidate parametric configurations capable of yielding the highest quality factor.Comment: 13 pages, 5 figures, 3 tables. One figure and one reference added; minor changes in the tex

    Violent or non-violent action? Wartime civilian resistance in Colombia and Mozambique

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    Why do some communities resist armed groups non-violently while others take up arms to do so? Recent research has advanced our knowledge of the causes and consequences of wartime civilian resistance. Yet, the factors explaining the emergence and outcomes of civilian resistance do not account for how people resist. Despite its important consequences for the politics and geography of war, the issue of why civilians engage in violent or non-violent forms of resistance remains poorly understood. We rely on extensive original fieldwork to examine within-case and cross-case variation in violent and non-violent resistance campaigns during the Mozambican and Colombian civil wars. We argue that forms of resistance are linked to prior experiences of collective action, normative commitments, and the role of local political entrepreneurs. Previous experiences make repertoires of resistance “empirically” available, while prevailing local social and cultural norms make them “normatively” available. Political entrepreneurs activate and adapt what is empirically and normatively available to mobilize support for some forms of action and against others. Our analysis advances emerging research on wartime civilian agency and has significant implications for theories of armed conflict, civil resistance, and contentious politics more broadly.NWOInstitutions, Decisions and Collective Behaviou

    Partial purification and MALDI-TOF MS analysis of UN1, a tumor antigen membrane glycoprotein.

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    UN1 is a membrane glycoprotein that is expressed in immature human thymocytes, a subpopulation of peripheral T lymphocytes, the HPB acute lymphoblastic leukemia (ALL) T-cell line and fetal thymus. We previously reported the isolation of a monoclonal antibody (UN1 mAb) recognizing the UN1 protein that was classified as "unclustered" at the 5th and 6th International Workshop and Conference on Human Leukocyte Differentiation Antigens. UN1 was highly expressed in breast cancer tissues and was undetected in non-proliferative lesions and in normal breast tissues, indicating a role for UN1 in the development of a tumorigenic phenotype of breast cancer cells. In this study, we report a partial purification of the UN1 protein from HPB-ALL T cells by anion-exchange chromatography followed by immunoprecipitation with the UN1 mAb and MALDI-TOF MS analysis. This analysis should assist in identifying the amino acid sequence of UN

    Comment: Superconducting transition in Nb nanowires fabricated using focused ion beam

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    In a recent paper Tettamanzi et al (2009 Nanotechnology \bf{20} 465302) describe the fabrication of superconducting Nb nanowires using a focused ion beam. They interpret their conductivity data in the framework of thermal and quantum phase slips below TcT_c. In the following we will argue that their analysis is inappropriate and incomplete, leading to contradictory results. Instead, we propose an interpretation of the data within a SN proximity model.Comment: 3 pages, 1 figure accepted in Nanotechnolog

    Characterization of translationally controlled tumour protein from the sea anemone Anemonia viridis and transcriptome wide identification of cnidarian homologues

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    Gene family encoding translationally controlled tumour protein (TCTP) is defined as highly conserved among organisms; however, there is limited knowledge of non-bilateria. In this study, the first TCTP homologue from anthozoan was characterised in the Mediterranean Sea anemone, Anemonia viridis. The release of the genome sequence of Acropora digitifera, Exaiptasia pallida, Nematostella vectensis and Hydra vulgaris enabled a comprehensive study of the molecular evolution of TCTP family among cnidarians. A comparison among TCTP members from Cnidaria and Bilateria showed conserved intron exon organization, evolutionary conserved TCTP signatures and 3D protein structure. The pattern of mRNA expression profile was also defined in A. viridis. These analyses revealed a constitutive mRNA expression especially in tissues with active proliferation. Additionally, the transcriptional profile of A. viridis TCTP (AvTCTP) after challenges with different abiotic/biotic stresses showed induction by extreme temperatures, heavy metals exposure and immune stimulation. These results suggest the involvement of AvTCTP in the sea anemone defensome taking part in environmental stress and immune responses

    Procedures for high quality RNA extraction from Paracentrotus lividus (LAMARCK, 1816) embryos and gonadal tissue

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    The extraction protocol described below is part of the CISAS project, aimed at the realization, within CNR, of an “International Centre of advanced study in environment, ecosystem and human health”. In this report we describe a RNA extraction protocol from Paracentrotus lividus embryos and gonadal tissue

    Surgery versus stereotactic radiotherapy for treatment of pulmonary metastases. A systematic review of literature

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    It is not clear as to which is the best treatment among surgery and stereotactic radiotherapy (SBRT) for lung oligometastases. A systematic review of literature with a priori selection criteria was conducted on articles on the treatment of pulmonary metastases with surgery or SBRT. Only original articles with a population of patients of more than 50 were selected. After final selection, 61 articles on surgical treatment and 18 on SBRT were included. No difference was encountered in short-term survival between pulmonary metastasectomy and SBRT. In the long-term surgery seems to guarantee better survival rates. Mortality and morbidity after treatment are 0-4.7% and 0-23% for surgery, and 0-2% and 4-31% for SBRT. Surgical metastasectomy remains the treatment of choice for pulmonary oligometastases. Patients with metastatic cancer with a limited number of deposits may benefit from surgical removal or irradiation of tumor nodules in addiction to chemotherapy. Surgical resection has been demonstrated to improve survival and, in some cases, can be curative. Stereotactic radiotherapy is emerging as a less invasive alternative to surgery, but settings and implications of the two treatments are profoundly different. The two techniques show similar results in the short-term, with lower complications rates for radiotherapy, while in the long-term surgery seems to guarantee higher survival rates

    Esperimento pilota mirato all’analisi dell’effetto della stimolazione immunitaria su A. viridis, finalizzato alla produzione di composti biologicamente attivi

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    L’esperimento mira a valutare l’eventuale attività antibatterica di peptidi prodotti da individui di Anemonia viridis in seguito a stimolazione immunitaria e quindi alla realizzazione di un protocollo riproducibile e ottimizzato per la produzione di tali composti

    Applicazione di un protocollo di immuno-stimolazione su individui di Pracambarus clarkii mirato alla produzione di peptidi con attivitĂ  biologica

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    Uno dei principali problemi inerenti l’identificazione e l’analisi di nuovi peptidi naturali di origine marina è la disponibilità in termini quantitativi del materiale bioattivo (Cragg et al., 1997). Infatti, le concentrazioni di tali peptidi negli invertebrati marini sono spesso meno del 10-6 % del peso umido, ed il loro rendimento a seguito delle procedure di estrazione tradizionali risulta ancora più basso. Tuttavia, sono molteplici i fattori che possono influenzare l'esito della identificazione degli Anti Microbial Peptides (AMP), come le variazioni geografiche e stagionali (sito di campionamento), le diverse fasi della vita (specie pelagiche o bentoniche), l'età, il sesso e lo stato fisiologico (malattia, allevamento, muta). A causa della difficoltà nell’ottenere quantità sufficienti di composti bioattivi, potrebbe essere più produttivo dissezionare in diversi tessuti/organi gli invertebrati selezionati per poi estrarre il materiale da saggiare (Haug et al., 2002a, 2002b, 2004) ciò al fine di separare i peptidi di interesse da migliaia di sostanze inattive. Dividere gli organismi in parti differenti selezionando ciascun tessuto potrebbe anche fornire l'indicazione se l'animale produce da sé il principio attivo o se esso proviene dalla dieta o ancora è associato a parassiti o microrganismi. La maggior parte degli AMP marini sono stati di fatto isolati dal compartimento sangue, sia dall’emolinfa/fluido celomatico (sangue intero) o dagli emociti/celomociti (cellule del sangue). Alcuni peptidi tuttavia sono stati scoperti e isolati da altri tessuti, ma essendo questi circondati (negli invertebrati marini) dagli emociti/celomociti, è possibile che provengano da questi ultimi. Inoltre tutte le variabili analitiche hanno una potenziale influenza sul risultato sia in termini quantitativi che qualitativi oltre che per la stabilità del campione anche per la riproducibilità del protocollo. Tra queste variabili ricadono le condizioni di conservazione del campione (tempo trascorso dall’estrazione, la temperatura prima dell’estrazione ed alla separazione, il congelamento e la liofilizzazione), la tipologia del campione ed il metodo di prelievo, la separazione delle cellule dal sangue (velocità di centrifugazione, durata e temperatura), l’uso del tampone (tipo, pH, forza ionica e temperatura), l'uso e il tipo di anticoagulanti e cocktail inibitori della proteasi. Inoltre, dati bibliografici riportano come la stimolazione immunitaria determini un aumento sia quantitativamente che qualitativamente della produzione di peptidi antimicrobici. Per tale motivo si è proceduto ad effettuare un esperimento pilota per valutare se in tali condizioni fosse superiore la quantità di piccoli peptidi sintetizzati rispetto ad individui non stimolati e se nei differenti tempi di stimolazione selezionati, emergesse una differenziazione a carico dei peptidi prodotti in relazione ad una possibile attività di natura antibatterica
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