23 research outputs found
Levels of vibration transmitted to the operator of the tractor equipped with front axle suspension
In recent years the comfort and the preservation of the health of the operators became central issues in the evolution of agricultural machinery and led to the introduction of devices aimed at improving working conditions. Thereby, for instance, the presence of air conditioner, soundproof cab and driver seat suspension became normal on agricultural tractors. The vibrations are one of the most complex issues to deal with, being determined by the characteristics and interaction of elements such as tyres, axles, mainframe, cab and seat suspension. In this respect, manufacturers are trying to improve their products, even integrating these elements with new devices such as the suspension on the front axle of the tractor, aimed at reducing the level of vibrations during the transfers at high speed. One of these underwent tests at CRA-ING. Since its purpose is to reduce the level of vibration transmitted to the driver, their measurements in different points of the tractor and in different operating conditions, were compared in order to evaluate the effectiveness of the device, expressed as time of exposure. The suspension system of the front axle is designed to absorb the oscillations (especially pitching) determined by irregularities in the road surface, allowing an increased control of the vehicle at high speed, as demonstrated by the test results and confirmed by the driving impressions outlined by the operator. The action of the device under these conditions results in an increase of the exposure time, important fact because of the relevance of the road transfer operations of tractors with mounted implements or trailers to tow and of the tendency to increase the speed limit for the road tractors (in Germany were brought to 50 km h–1 for several years). The action just described is less evident with increasing irregularity of the road surface and with the decrease of the travel speed. Nevertheless, in such conditions, the device appears to positively work along the other directions, in particular in the Z-axis, improving the action of the suspension of the driver seat
Marine phycotoxin levels in shellfish-14 years of data gathered along the Italian coast
Along the Italian coasts, toxins of algal origin in wild and cultivated shellfish have been reported since the 1970s. In this study, we used data gathered by the Veterinary Public Health Institutes (IZS) and the Italian Environmental Health Protection Agencies (ARPA) from 2006 to 2019 to investigate toxicity events along the Italian coasts and relate them to the distribution of potentially toxic species. Among the detected toxins (OA and analogs, YTXs, PTXs, STXs, DAs, AZAs), OA and YTX were those most frequently reported. Levels exceeding regulatory limits in the case of OA (≤2,448 μg equivalent kg-1) were associated with high abundances of Dinophysis spp., and in the case of YTXs (≤22 mg equivalent kg-1) with blooms of Gonyaulax spinifera, Lingulodinium polyedra, and Protoceratium reticulatum. Seasonal blooms of Pseudo-nitzschia spp. occur all along the Italian coast, but DA has only occasionally been detected in shellfish at concentrations always below the regulatory limit (≤18 mg kg-1). Alexandrium spp. were recorded in several areas, although STXs (≤13,782 μg equivalent kg-1) rarely and only in few sites exceeded the regulatory limit in shellfish. Azadinium spp. have been sporadically recorded, and AZAs have been sometimes detected but always in low concentrations (≤7 μg equivalent kg-1). Among the emerging toxins, PLTX-like toxins (≤971 μg kg-1 OVTX-a) have often been detected mainly in wild mussels and sea urchins from rocky shores due to the presence of Ostreopsis cf. ovata. Overall, Italian coastal waters harbour a high number of potentially toxic species, with a few HAB hotspots mainly related to DSP toxins. Nevertheless, rare cases of intoxications have occurred so far, reflecting the whole Mediterranean Sea conditions
Interplay of the Ca2+-binding protein DREAM with presenilin in neuronal Ca2+ signaling
The Ca(2+)-binding protein DREAM regulates gene transcription and Kv potassium channels in neurons but has also been claimed to interact with presenilins, which are involved in the generation of beta-amyloid and in the regulation of the Ca(2+) content in the endoplasmic reticulum. The role of DREAM in Ca(2+) homeostasis was thus explored in SH-SY5Y cells stably or transiently overexpressing DREAM or a Ca(2+)-insensitive mutant of it. The overexpression of DREAM had transcriptional and post-transcriptional effects. Endoplasmic reticulum Ca(2+) and capacitative Ca(2+) influx were reduced in stably expressing cells. The previously shown down-regulation of Na(+)/Ca(2+) exchanger 3 expression was confirmed; it could cause a local increase of subplasma membrane Ca(2+) and thus inhibit capacitative Ca(2+) influx. DREAM up-regulated the expression of the inositol 1,4,5-trisphosphate receptor and could thus increase the unstimulated release of Ca(2+) through it. The transient coexpression of DREAM and presenilin potentiated the decrease of endoplasmic reticulum Ca(2+) observed in presenilin-overexpressing cells. This could be due to a direct effect of DREAM on presenilin as the two proteins interacted in a Ca(2+)-independent fashion
I percorsi assistenziali del malato oncologico terminale: uno studio retrospettivo
Sono stati studiati retrospettivamente
i percorsi assistenziali territoriali e residenziali degli ultimi
3 mesi di vita dei deceduti per cancro nel distretto della Vallagarina
(TN) nel 2008. Obiettivo. Descrivere i percorsi degli
ultimi 90 giorni di vita, di tutti i deceduti per cancro. Metodi.
Sono state utilizzate più fonti: schede di dimissione ospedaliera,
sistemi informativi aziendali, banca dati del servizio
di cure palliative (CP), documentazione cartacea dei servizi
di CP e domiciliari e intervistati i familiari dei pazienti seguiti
dai medici di medicina generale (MMG). Risultati. Sono
stati individuati 4 percorsi: Persone assistite prevalentemente
dal MMG, in Residenze Sanitarie Assistenziali (RSA),
in RSA a sede Ospedaliera o in Lungodegenza, dalle CP. L’incidenza
delle ospedalizzazioni varia in base al tipo di percorso
(25.5% delle potenziali giornate di assistenza per il percorso
MMG, 1.3% il percorso CP) come anche durata media
dei ricoveri ospedalieri (18.7 giorni nel percorso MMG, 5.6
giorni nel percorso CP). In pochi casi il MMG attiva forme
di assistenza domiciliare a intensità intermedia quali l’Assistenza
Domiciliare Integrata (10.8% delle persone) o l’Assistenza
Domiciliare Programmata (12.7% delle persone). I caregiver
delle persone del percorso MMG vorrebbero avere maggiori
informazioni sul quadro clinico e sulle varie possibilitÃ
di assistenza domiciliare, per partecipare alle scelte. Solo pochi
affermano che non avrebbero avuto la possibilità di un’assistenza
domiciliare. Conclusioni. I pazienti assistiti dal MMG
e quelli assistiti dalle CP hanno percorsi molto diversi. La carenza
di informazioni ricevute dai caregiver sembra giocare
un ruolo importante nel condizionare i diversi percorsi
Dynamic-energetic balance of agricultural tractors: active systems for the measurement of the power requirements in static tests and under field conditions
Modern tractors are characterized by the introduction of devices designed to increase the operative performances of the machines, such as systems for monitoring and controlling various functions (through a massive use of electronics and hydraulics), or deputed to improve the comfort of the driver (paying more attention to ergonomics, air-conditioning, noise and vibration). Such devices need energy to be operated, affecting the energetic balance of the tractor. In this context, the availability of suitable methodologies and instrumental systems could be useful to provide objective, accurate and reliable measurements of the performances of the tractors under different conditions, also considering the power requirements from ancillary services and/or simulating the coupling with operating machines. The tests on the performances of tractors are now made using different methods, including the trial codes issued by the OECD Codes. Beyond their undoubted validity, they fix standard test conditions that often do not adequately represent the operative reality, so that, much remains to investigate on the actual performances provided by the tractors. From this point of view and with reference to fixed point tests, a test bench was developed for the measurement of the power required by various devices, such as transmission and air conditioning. It was used in experimental tests on a tracked tractor and on a wheeled tractor, aimed at validating the test device, measuring the power absorption related to the rotational speed of the organs of propulsion and to the characteristics curves, in order to quantify the power drawn by the transmission and by the air conditioning and assess the residual power for other tractor functions. As to field conditions, a study is being conducted at CRA-ING, within the project PTO (Mi.P.A.A.F.), to develop a mobile test bench aimed at evaluating the power required by different operations, such as self displacement, traction, use of power take off, their combination. The system simulates such operations by applying to the tractor, by means of a system of sensors and actuators operated by feedback signals, work cycles combining force of traction, p.t.o. torque, hydraulic power, derived from data recorded during real field test with agricultural machines
Plasma-membrane calcium pumps and hereditary deafness
In mammals, four different genes encode four PMCA (plasma-membrane Ca(2+)-ATPase) isoforms. PMCA1 and 4 are expressed ubiquitously, and PMCA2 and 3 are expressed predominantly in the central nervous system. More than 30 variants are generated by mechanisms of alternative splicing. The physiological meaning of the existence of so many isoforms is not clear, but evidently it must be related to the cell-specific demands of Ca(2+) homoeostasis. Recent studies suggest that the alternatively spliced regions in PMCA are responsible for specific targeting to plasma membrane domains, and proteins that bind specifically to the pumps could contribute to further regulation of Ca(2+) control. In addition, the combination of proteins obtained by alternative splicing occurring at two different sites could be responsible for different functional characteristics of the pumps
Activities of mitochondrial complexes correlate with nNOS amount in muscle from ALS patients
The pathogenesis of amyotrophic lateral sclerosis (ALS) is poorly understood. Increased levels of free radicals derived from nitric oxide (NO), the product of nitric oxide synthase (NOS), may damage mitochondrial function leading to motor neurone death. Previous studies demonstrated a specific impairment of mitochondrial function in skeletal muscle of ALS patients. In order to verify a pathogenetic relationship between neuronal NOS (nNOS) and mitochondrial function, we studied nNOS expression by Western blot and mitochondrial enzyme activity by spectrophotometric assays in muscle biopsies of 16 sporadic ALS patients and 16 controls subjects. We observed a reduced activity of respiratory chain complexes with mitochondrial encoded subunits and a lower nNOS amount in ALS muscles. There was a direct correlation between levels of nNOS and values of mitochondrial enzymes function. In ALS muscles we found normal levels of manganese superoxide dismutase (SOD2) that is assumed as related to mitochondrial DNA abnormalities. Our data suggest a beneficial role for NO to mitochondrial function and lead to the hypothesis of a common oxidative damage in motor neurones and skeletal muscle in sporadic ALS patients
Levels of vibration transmitted to the operator of the tractor equipped with front axle suspension
In recent years the comfort and the preservation of the health of the operators became central issues in the evolution of agricultural machinery and led to the introduction of devices aimed at improving working conditions. Thereby, for instance, the presence of air conditioner, soundproof cab and driver seat suspension became normal on agricultural tractors. The vibrations are one of the most complex issues to deal with, being determined by the characteristics and interaction of elements such as tyres, axles, mainframe, cab and seat suspension. In this respect, manufacturers are trying to improve their products, even integrating these elements with new devices such as the suspension on the front axle of the tractor, aimed at reducing the level of vibrations during the transfers at high speed. One of these underwent tests at CRA-ING. Since its purpose is to reduce the level of vibration transmitted to the driver, their measurements in different points of the tractor and in different operating conditions, were compared in order to evaluate the effectiveness of the device, expressed as time of exposure. The suspension system of the front axle is designed to absorb the oscillations (especially pitching) determined by irregularities in the road surface, allowing an increased control of the vehicle at high speed, as demonstrated by the test results and confirmed by the driving impressions outlined by the operator. The action of the device under these conditions results in an increase of the exposure time, important fact because of the relevance of the road transfer operations of tractors with mounted implements or trailers to tow and of the tendency to increase the speed limit for the road tractors (in Germany were brought to 50 km h–1 for several years). The action just described is less evident with increasing irregularity of the road surface and with the decrease of the travel speed. Nevertheless, in such conditions, the device appears to positively work along the other directions, in particular in the Z-axis, improving the action of the suspension of the driver seat