Polyimide bonded graphite fluoride: A new long life solid lubricant coating

Solid lubricant film consisting of polyimide varnish as binder and graphite fluoride as lubricant is described. Comparative wear tests with other solid lubricants were conducted and results are shown in graph form. Test equipment used in conducting wear tests is reported

A new solid lubricant

Friction and wear life studies on burnished films of the compound graphite fluoride have demonstrated its potential as a solid lubricant material. It is effective in moist air, dry air, or in dry argon at temperatures up to approximately 400 degrees C

Preliminary investigation of graphite fluoride /CF sub x/ sub n as a solid lubricant

Friction and wear tests with graphite fluoride lubrican

Friction and wear behavior of graphite fiber reinforced polymide composites

The friction and wear rate characteristics of 50/50 (weight percent) graphite fiber polyimide composites were studied by sliding metallic hemispherically tipped riders against disks made from the composites. Two different polyimides and two different graphite fibers were evaluated. Also studied were such variables as the effect of moisture in an air atmosphere; the effect of temperature; and the effect of different sliding speeds. In general, wear to the the metallic riders was negligible, and composite wear increased at a constant rate as a function of number of sliding cycles

Activité de recherche du Centre d'expérimentation agricole et forestière (Rome) sur le pin d'Alep

Les activités de recherche du pin d'Alep qui sont actuellement en cours dans l'Institut et qui s'étendent à un domaine d'enquête particulièrement vaste va de l'amélioration génétique aux tests de culture intensive

Life-Cycle Cost Estimation for High-Speed Vehicles: from the engineers’ to the airline’s perspective

This paper aims at upgrading the holistic Cost Estimation methodology for High-Speed Vehicles already developed by Politecnico di Torino and the European Space Agency (ESA) to encompass different stakeholders’ perspectives. In details, the presented methodology combines International Air Transport Association (IATA) best practices with a detailed Life- Cycle Cost (LCC) assessment, which includes the evaluation of Research, Development, Test and Evaluation (RDTE) Costs, Production costs and of Direct and Indirect Operating Costs (DOC and IOC). The integrated approach allows to further extend the capabilities of the inhouse developed HyCost tool to support all the actors of the product value-chain (including engineers, manufacturers, airlines and customers) in assessing the economic sustainability of a newly under-development high-speed vehicle. However, considering the need of providing all these cost analyses perspectives since the early design stages, the derived Cost Estimation Relationships are mainly derived on statistical bases. To cope with the uncertainties that affect the initial statistical population and consequently, the CERs, this paper presents each cost item together with the estimation of related prediction intervals. Finally, results of the application of the upgraded cost estimation methodology and of the upgraded tool to the LAPCAT MR2.4 high-speed civil transport are reported and discussed

Valorisation productive de zones dégradées à l'aide de plantations forestières : un exemple d'expérimentation en Sardaigne.

Décrit des interventions expérimentales réalisées en 1986-87 en Sardaigne afin de : - identifier les espèces forestières appropriées - mettre au point des techniques de préparation appropriées

FRI0499 ACROMEGALY ARTROPATHY: IS THERE SOMETHING MORE BEHIND THE PAIN? A CROSS-SECTIONAL STUDY TO EVALUATE RHEUMATIC DISEASE IN GROWTH HORMONE SECRETING TUMOR PATIENTS

Background:Acromegaly is a rare disease with a remarkable impact on patients, both in terms of life expectancy and quality of life. Osteo-articular complications are one of the most frequently reported bothers. The "acromegaly artropathy" characterizes more than 70% of patients at diagnosis. Artropathy affects both spine and peripheral joints. A recent prospective study documented progression of acromegalic arthropathy identified as a worsening of osteophytes and joint space narrowing in 72–74% of patients despite long-term biochemical control. In addiction the Literature has occasionally reported cases of simultaneous presence of rheumatic diseases (rheumatoid arthritis, polymyalgia rheumatica, undifferentiated connective tissue diseases) and acromegaly and in all these cases the treatment has been delayed, because of wrong symptoms attribution to acromegaly artropathy.Objectives:The primary goal of the study is to better characterize joint pain in acromegaly patients and to evaluate the prevalence of rheumatic disease in growth hormone (GH) secreting pituitary tumor patients.Methods:We enrolled 20 acromegaly subjects (AS) and 20 control subjects (CS). In each subject immunological pattern (rheumatoid factor – RF; antinuclear antibodies - ANA, ENA; anti-citrullinated protein antibodies - ACPA; erythrocyte sedimentation rate – ESR) has been evaluated; they, also, underwent bilateral joint ultrasound of hands and wrists and nail capillaroscopy. The Chi square test and the Fisher's exact test were used to evaluate the association between binary variables, while the Spearman's test to evaluate the correlation of continuous ones. A multiple or logistic regression model was calculated in order to define the association between the capillaroscopic alterations and other detected variables.Results:Articular pain emerged as significantly more frequent in AS (p = 0.0269). No statistically significant differences are detected regarding immunological pattern. ANA and ENA screening resulted positive in 10% in AS and in 5% in CS. No IgA ACPA were detected in AS or CS, while IgG ACPA were positive only in one AS subject. No significant differences were detected between IgM and IgG RFin the two groups (AS 5% and CS 0%). Three fold higher IgG FR in AS compared to CS were detected. ESR levels were significantly higher than CS (p = 0.0405), as well as increased power doppler (PWD) articular uptake (AS 30% vs CS 5% p 0.081). The capillaroscopic evaluation showed a significant difference in almost each parameter that has been evaluated (logistic regression: number of enlargement p 0.004, hemorragies p 0.01 and capillaries p 0.001), showing a moderate-severe microangiopathy in AS. Interestingly, analyzing only the acromegaly cohort, we noticed higher GH levels at the enrollment in patients which developed capillary enlargements (GH: 0.95 ng/ml IQ 0,6-1,6) compared to other ones (GH: 0.55 ng/ml IQ 0.4-0.7; p = 0.08) and a significant lower number of hemorrhages (p = 0.02) in patients treated with GH antagonist pegvisomant.Conclusion:Our results demonstrated that joint damage in acromegaly does not seem to have an autoimmune etiology. Therefore, articular damage is mechanical and increased ESR and PWD alterations seems to confirm the presence of an inflammatory component. In addition, acromegaly is characterized by a microvascular pattern of moderate-severe microangiopathy, without correlation to IGF-I, but GH levels. Although requiring further confirmatory studies, our preliminary results seem to indicate how the capillaroscopic examination could be useful to detect earlier microangiopathy and to identify patients with a greater risk of macroangiopathy development..References:[1]Claessen KMJA et al. Bone and joint disorders in acromegaly. Neuroendocrinology. 2016;103(1):86-95.[2]Örük G et al. Is every joint symptom related to acromegaly? Endocrine. 2013 Apr;43(2):404-11.Disclosure of Interests:None declare