654 research outputs found

    The Growth of Fetal Human Sensory Ganglion Neurons in Culture: A Scanning Electron Microscopic Study

    Get PDF
    Sensory neurons of 8-week human fetal dorsal root ganglia were dissociated into single cells by trypsinization and cultured on coverslips for 4 months, in either serum-containing or serum-free chemically defined media. At different times the cultures were fixed and prepared for scanning electron microscopy. Fetal sensory neurons in culture regenerated axons within 24 hours which were characterized by axonal growth cones at their tips and the neuronal perikarya assumed spherical or a bonnet-like morphology

    Survival and Growth of Adult Human Oligodendrocytes in Culture: Scanning Electron Microscopy

    Get PDF
    The oligodendrocytes in culture serve as an important model for the study of demyelination diseases. We have previously originated a method of isolating human oligodendrocytes. In order to establish their three dimensional morphology, scanning electron microscopy of the cultured oligodendrocytes was performed. The oligodendrocytes bulk isolated from adult human brain were maintained in culture for more than 2 months. At the various periods in culture, the cells were studied by scanning electron microscopy and immunofluorescence staining using marker antibodies for the identification of oligodendrocytes. The three dimensional organization and the surface morphology of the cultured oligodendrocytes were investigated. They displayed an extensive network of the cell processes and characteristic surface morphology

    Bilateral internal carotid artery dissection associated with prior syphilis: a case report and review of the literature

    Get PDF
    Bilateral internal carotid artery dissection is a rare entity, and its presentation may include cerebral ischemia. We describe the case of a 69-year-old man with ischemic stroke and radiological evidence of intimal flap of both internal carotid arteries suggestive for dissection. During the hospitalization, our patient was found positive for a previous syphilis infection. We conducted a review of the literature, with evidence of a few cases of ischemic stroke presumably related to a prior syphilis. The absence of major cardiovascular risk factors in our patient leads us to believe that an etiopathogenetic link may exist between these two conditions

    ground source heat pump systems in historical buildings two italian case studies

    Get PDF
    Abstract Reducing the energy demand of buildings has become one of the key points of the European Union. The issue related to the air conditioning of old and historical buildings is nowadays one of the most important field of operation for the primary energy saving and, at the same time, for the reduction of the CO 2 emission. The recent development of heat pump able to rise the supply of high temperature at the condenser side makes this technology suitable for the application also in historical buildings that are characterized by low thermal insulation and high thermal capacitance. In this context, the ground source heat pump systems can be used for both heating and cooling. The aim of this work is to analyze the thermal behavior of two historical buildings located in Italy, in Venice and Florence respectively. Detailed computer simulations of the buildings have been carried out by means of a transient calculation tool TRNSYS. Energy simulations of GSHP systems have been performed and a comparison with a common plant system using a gas boiler for heating and air-to-water chiller for cooling has been carried out

    Material recognition with a 252Cf source

    Get PDF
    Material recognition is studied by measuring simultaneously the transmission of neutron and gamma rays produced by a time-tagged 252Cf source. Light elements (C,N,O) are identified by using the measured transmission versus neutron time of flight. The yield of the transmitted gamma ray as a function of energy provides high precision identification of the atomic number of the sample up to Z=83 . A tomography system, currently under construction, is described

    Coproduced urban water services: When technical and governance hybridisation go hand in hand

    Get PDF
    This study questions the processes of technical and governance hybridisation in the coproduction of water services in cities of the Global South. The existing literature addresses the compensatory role that water services coproduction plays in urban and peri-urban areas, where access to centralised and reliable water resources is often lacking. However, less research focuses on the evolution of coproduced practices in relation to wider transitions of urban spaces, water resources, centralised infrastructure, and service delivery strategies. Still, the resulting technical and governance configurations stemming from these situations are largely unexplored. This study considers four cities, namely, Hanoi (Vietnam), Dar es Salaam (Tanzania), Cochabamba (Bolivia), and Addis Ababa (Ethiopia). All our case studies are somewhat characterised by rapid land-use changes, juxtaposition of rural and urban activities, varying urban typologies, and increasing poverty, sociospatial inequality, and exclusionary service provision. We draw on data collected from field surveys and participatory workshops with inhabitants and institutional actors between 2017 and 2020 as part of a recent research project. We explore the evolution of water coproduction from technological and governance perspectives. The cases analysed in the research highlight that the time and social development of water coproduction do not follow a linear path. It is rather characterised by cycles of emergence, maturation, and decline. It may build upon pre-existing forms of community-based water management that were established in rural areas (for irrigation or water harvesting, for instance). The results show that water coproduction may have different evolutions, entailing different hybridisation processes. Water coproduction can be characterised by either complementary or concurrent service configurations, by blurring actor categories, and by different drivers in the hybridisation process. Ultimately, evolution in urban coproduced practices appears as a process of technical and governance hybridisation, rather than as final and fixed hybrid systems

    The effect of customer perceived value on customer satisfaction: a case study of Malay upscale restaurants

    Get PDF
    Stiff competition and increasingly high operating costs have driven many international and domestic players to introduce new outlet concepts. Malay fine dining, upscale restaurant segment is gaining popularity among Malaysian, especially in Kuala Lumpur. This study examined the effect of perceived value on customer satisfaction in Malay upscale restaurants in terms of emotional responses, monetary prices, behavioral price and reputation. Primary data were gathered from 170 questionnaires returned by respondents from five Malay upscale restaurants in Kuala Lumpur, and statistically analysed using SPSS version 21. The findings of this study revealed that monetary prices had a high positive relationship with customer satisfaction. In addition, the beta value for emotional responses (β=0.530, p<0.01), behavioral price (β=0.180, p<0.01) and reputation (β=0.168, p<0.01) also indicated the respective contributions made to customer satisfaction

    The Representation of Objects in Apraxia: From Action Execution to Error Awareness

    Get PDF
    Apraxia is a well-known syndrome characterized by the sufferer's inability to perform routine gestures. In an attempt to understand the syndrome better, various different theories have been developed and a number of classifications of different subtypes have been proposed. In this article review, we will address these theories with a specific focus on how the use of objects helps us to better understand upper limb apraxia. With this aim, we will consider transitive vs. intransitive action dissociation as well as less frequent types of apraxia involving objects, i.e., constructive apraxia and magnetic apraxia. Pantomime and the imitation of objects in use are also considered with a view to dissociating the various different components involved in upper limb apraxia. Finally, we discuss the evidence relating to action recognition and awareness of errors in the execution of actions. Various different components concerning the use of objects emerge from our analysis and the results show that knowledge of an object and sensory-motor representations are supported by other functions such as spatial and body representations, executive functions and monitoring systems

    Variability of clinical target volume delineation for rectal cancer patients planned for neoadjuvant radiotherapy with the aid of the platform Anatom-e

    Get PDF
    Objective: Delineation of treatment volumes is a major source of uncertainties in radiotherapy (RT). This is also true for rectal cancer patients undergoing neoadjuvant RT, with a potential impact on treatment quality. We investigated the role of the digital platform Anatom-e (Anatom-e Information Sytems Ltd., Houston, Texas) in increasing the compliance to follow a specific treatment protocol in a multicentric setting. Materials and methods: Two clinical cases of locally advanced rectal cancer were chosen. Participants were instructed to follow the 2009 Radiation Therapy Oncology Group consensus atlas and asked to manually segment clinical target volumes (CTVs), for both patient 1 and 2, on day 1 with and without the use of Anatom-e. After one week (day 2), the same radiation oncologist contoured again, with and without Anatom-e, the same CT series. Intraobserver (Intra-OV) and interobserver (Inter-OV) variability were evaluated with the Dice similarity coefficient (DSC), the Hausdorff distance (HD) and mean distance to agreement (MDA). Results: For clinical case 1, no significant difference was found for Intra-OV and Inter-OV. For clinical case 2, no significant difference was found for Intra-OV but a statistically significant difference was found for Inter-OV in DSC when using or not the platform. Mean DCS was 0.65 (SD: ±0.64; range: 0.58–0.79) for day 1 vs reference volume without Anatom-e and 0.72 (SD: ±0.39; range: 0.67–0.77) (p = 0.03) with it. Mean MDA was lower with Anatom-e (3.61; SD: ±1.33; range: 2.85–4.78) than without (4.14; SD: ±2.97; range: 2.18–5.21), with no statistical significance (p = 0.21) The use of Anatom-e decreased the SD from 2.97 to 1.33. Mean HD was lower with Anatom-e (26.06; SD: ±2.05; range: 24.08–32.62), with no statistical significance (p = 0.14) compared to that without (31.39; SD: ±1.31; range: 26.14–48.72). Conclusions: The use of Anatom-e decreased the Inter-OV in the CTV delineation process for locally advanced rectal cancer with complex disease presentation planned for neoadjuvant RT. This system may be potentially helpful in increasing the compliance to follow shared guidelines and protocols. Keywords: Rectal cancer, Neoadjuvant radiotherapy, Interobserver variability, Contouring, Target volume delineatio
    • …
    corecore