108 research outputs found

    Cronache tecniche di ingegneria dalla Toscana: "Adeguamento sismico di un edificio a due piani a Firenze: taglio di due pilastri centrali con messa in forza di rinforzo in acciaio" Progettista delle strutture: Prof. Ing. Paolo SPINELLI Collaborazione progetto strutturale: Dott. Ing. Alessio MARGIOTTA Direzione lavori: Dott. Ing. Massimiliano CECCONI

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    All’interno dei locali di un edificio esistente, situato a Firenze e costituito da due piani fuori terra, vi è stata l’esigenza di realizzare uno spazio atto ad ospitare conferenze, congressi e summit dei vertici dirigenziali dell’azienda: si doveva quindi realizzare un nuovo Auditorium a piano terra e i relativi locali dovevano essere riorganizzati in modo tale da rispondere alle nuove esigenze funzionali. Il maggior ostacolo da superare era rappresentato dalla presenza di due pilastri dell’edificio che risultavano incompatibili con le esigenze di visibilità e fruibilità della sala. D’altro canto la loro rimozione non era facile in quanto senza di essi si sarebbe avuta una luce libera di quasi 15 metri e per l’appunto essi appartenevano ad una campata che, oltre a portare il solaio di piano primo di luce 9.90 metri, si faceva carico anche delle travi di copertura aventi luce 20 m; Si è deciso di seguire la strada dell’eliminazione dei due pilastri e del conseguente rinforzo della campata con un’opportuna struttura in acciaio affiancata a quella in C.A. esistente

    Chipping machines: disc and drum energy requirements

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    Air pollution and fossil fuel reserves exhaustion are increasing the importance of the biomass-derived products, in particular wood, as source of clean and renewable energy for the production of electricity or steam. In order to improve the global efficiency and the entire production chain, we have to evaluate the energetic aspects linked to the process of transformation, handling and transport of these materials. This paper reports results on a comparison between two chippers of similar size using different cutting technology: disc and drum tool respectively. During trials, fuel consumption, PTO torque and speed, processing time and weight of processed material were recorded. Power demand, fuel consumption, specific energy and productivity were computed. The machine was fed with four different feedstock types (chestnut logs, poplar logs, poplar branches, poplar sawmill residues). 15 repetitions for each combination of feedstock-tool were carried out. The results of this study show that the disc tool requires, depending on the processed material, from 12 to 18% less fuel per unit of material processed than the drum tool, and consequently, from 12 to 16% less specific energy. In particular, the highest difference between tools was found in branches processing whereas the smallest was in poplar logs. Furthermore the results of the investigation indicate, that, in testing conditions, the productivity of drum tool is higher (8%) than disc tool

    Low-cost electrochemical impedance spectroscopy system for corrosion monitoring of metallic antiquities and works of art

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    Electrochemical impedance spectroscopy (EIS) is recognized to be a powerful and noninvasive technique to test the integrity of protective coatings on memorials, but commercial EIS systems are rather costly though versatile devices. This paper describes a low cost and portable EIS system that is based on a compact digital signal processor (DSP) board and embeds the potentiostatic function so that it can be used without requiring an external potentiostat. The software that runs on the DSP is designed to analyze the electrochemical impedance only in a reduced frequency range in order to produce a simple corrosion alert result. The device is equipped with a digital interface and can be connected to a personal computer to carry out a complete frequency analysis and perform a more complex data processing

    Simulation of forest harvesting alternative processes and concept design of an innovative skidding winch focused on productivity improvement

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    In contexts in which mechanized harvesting is limited, such as in the northwestern Black Sea region of Turkey, it is important to improve timber harvesting productivity while preserving operators' safety and reducing environmental damage. This study aims to introduce a methodology in which the harvesting process is simulated with discrete-event simulation (DES) software in order to identify bottlenecks. An alternative process is compared to the original within the DES software, carrying out further steps oriented to the generation of new innovative product concepts. As a case study, the design of an innovative skidding winch is proposed. The development of the product was focused towards customer satisfaction by collecting customer requirements and identifying quality characteristics with a quality function deployment approach. Contradictions identified in the design phase were solved using the TRIZ contradiction toolkit, generating different product concepts. Inventive solutions provided by TRIZ were designed within parametric CAD software. The concepts were compared in a virtual environment, eventually selecting an optimal solution. The results showed that, with the concept adopted, it is possible to achieve a substantial increase in productivity, from 121% to 133%, in terms of kilograms of logs per hour deposited on the landing

    Frequency Dependence of Piles' Dynamic Stiffness

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    Technical BriefTechnical Brief 6: The evaluation of the dynamic behavior of deep foundations for Turbomachinery Modules is not a simple task due to uncertainties in the evaluation of the soil shear modulus and the approximations introduced with published literature formulas for complex stiffness (impedance) functions of piles. The direct measurement of the dynamic response of full scale piles can be an efficient method to reduce considerably these uncertainties and to get a reliable evaluation of the dynamic response of deep foundations. The above should also positively impact both the risks and the engineering schedule in the execution phase of the projects, reducing the dynamic analysis cases. The authors present herein the results of full-scale dynamic tests on piles, which have been performed by applying sinusoidal forces to their top

    Are interferon-gamma release assays reliable to detect tuberculosis infection in patients with rheumatoid arthritis treated with Janus kinase inhibitors

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    Screening for latent tuberculosis infection is recommended in patients with rheumatoid arthritis (RA) starting Janus kinase inhibitors (Jaki). Interferon (IFN)-gamma release assays (IGRAs) are increasingly used for this purpose. Jaki tend to decrease the levels of IFNs, questioning the reliability of IGRAs during treatment with these drugs. Objectives: To compare the performance of QuantiFERON-TB Gold Plus (QFT-P) and QFT Gold In-tube (QFT-GIT) in RA patients treated with Jaki. Methods: RA patients underwent QFT-P and QFT-GIT at baseline (T0), and after 3 (T3) and 12 months (T12) of treatment with Jaki. The agreement between the two tests was calculated. The agreement between IGRAs and tuberculin skin test (TST) or chest radiography at baseline was also determined. The variability of QTF-P results was longitudinally assessed. Results: Twenty-nine RA patients (F/M 23/6; median age/IQR 63/15.5 years; median disease duration/IQR 174/216 months) were enrolled. A perfect agreement was found between QFT-P and QFT-GIT at all times (Îş = 1). At T0, no agreement was recorded between IGRAs and TST (Îş = -0.08) and between TST and chest radiography (Îş = -0.07), a low agreement was found between QFT-P and chest radiography (Îş = 0.17). A variation of 33.3% in the results of QFT-P was recorded at T3 vs T0, of 29.4% at T12 vs T0, and of 11.8% at T12 vs T3. The median levels of IFN-Îł produced by lymphocytes in response to the mitogen of QFT-P decreased after 3 months followed by an increase after 12 months (not significant). No change in the median number of circulating lymphocytes was documented. Glucocorticoids intake was associated with a higher probability of negative or indeterminate IGRA results at T0 (p<0.0001). Conclusion: A response to IGRAs is detectable during treatment with Jaki. However, fluctuations in the results of IGRAs have been observed in the absence of correlation with clinical outcomes, thus challenging their interpretation

    Changes in bone turnover markers in patients without bone metastases receiving immune checkpoint inhibitors: An exploratory analysis

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    Immune checkpoint inhibitors (ICIs) has revolutionized the treatment of different advanced solid tumors, but most patients develop severe immune-related adverse events (irAEs). Although a bi-directional crosstalk between bone and immune systems is widely described, the effect of ICIs on the skeleton is poorly investigated. Here, we analyze the changes in plasma levels of type I collagen C-terminal telopeptide (CTX-I) and N-terminal propeptide of type I procollagen (PINP), reference makers of bone turnover, in patients treated with ICIs and their associ-ation with clinical outcome.A series of 44 patients affected by advanced non-small cell lung cancer or renal cell carcinoma, without bone metastases, and treated with ICIs as monotherapy were enrolled. CTX-I and PINP plasma levels were assessed at baseline and after 3 months of ICIs treatment by ELISA kits.A significant increase of CTX-I with a concomitant decreasing trend towards the reduction of PINP was observed after 3 months of treatment. Intriguingly, CTX-I increase was associated with poor prognosis in terms of treatment response and survival. These data suggest a direct relationship between ICIs treatment, increased osteoclast activity and potential fracture risk.Overall, this study reveals that ICIs may act as triggers for skeletal events, and if confirmed in larger pro-spective studies, it would identify a new class of skeletal-related irAEs

    Combination of chemotherapy and PD-1 blockade induces T cell responses to tumor non-mutated neoantigens

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    Here, we developed an unbiased, functional target-discovery platform to identify immunogenic proteins from primary non-small cell lung cancer (NSCLC) cells that had been induced to apoptosis by cisplatin (CDDP) treatment in vitro, as compared with their live counterparts. Among the multitude of proteins identified, some of them were represented as fragmented proteins in apoptotic tumor cells, and acted as non-mutated neoantigens (NM-neoAgs). Indeed, only the fragmented proteins elicited effective multi-specific CD4+ and CD8+ T cell responses, upon a chemotherapy protocol including CDDP. Importantly, these responses further increased upon anti-PD-1 therapy, and correlated with patients’ survival and decreased PD-1 expression. Cross-presentation assays showed that NM-neoAgs were unveiled in apoptotic tumor cells as the result of caspase-dependent proteolytic activity of cellular proteins. Our study demonstrates that apoptotic tumor cells generate a repertoire of immunogenic NM-neoAgs that could be potentially used for developing effective T cell-based immunotherapy across multiple cancer patients

    Receiver design for the REACH global 21-cm signal experiment

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    We detail the the REACH radiometric system designed to enable measurements of the 21-cm neutral hydrogen line. Included is the radiometer architecture and end-to-end system simulations as well as a discussion of the challenges intrinsic to highly-calibratable system development. Following this, we share laboratory results based on the calculation of noise wave parameters utilising an over-constrained least squares approach demonstrating a calibration RMSE of 80 mK for five hours of integration on a custom-made source with comparable impedance to that of the antenna used in the field. This paper therefore documents the state of the calibrator and data analysis in December 2022 in Cambridge before shipping to South Africa.Comment: 30 pages, 19 figure
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