391 research outputs found
Developing novel photocatalytic cementitious permeable pavements for depollution of contaminants and impurities in urban cities
Photocatalyst such as Titanium Dioxide (TiO2) has been recently introduced as a nanoparticle into cementitious permeable pavements. Combining photocatalytic compounds within concrete permeable pavements can aid with depollution of several contaminants found in urban water streams and air impurities. This paper presents research carried out at the Uni-versity of Greenwich, UK using photocatalytic concrete with varying percentages of TiO2 (0 %, 1% and 5%) to assess the levels depollution which can be achieved.Concrete samples were testing against the degradation of 2, 4-Dichlorophenoxyacetic Acid, a harmful chemical found in herbicides. This advanced oxidation process can aid in the re-duction of urban pollution from an air and water perspective, improving sustainability for urban cities. Self-cleaning benefits of photocatalytic concrete permeable pavements can be used to keep urban infrastructure cleaner and more aesthetically pleasing. Experimental tests were carried out on the characterisation of inorganics through X-Ray diffraction and Fourier Transform Infrared Spectroscopy to ensure that the structures of the concrete samples were not altered by addition of the na-noparticles (photocatalyst). Experimental results were compared to that found in previous literature and confirmed that the addition of 5% TiO2 did not affect the structure of the concrete samples and can be a viable option used in urban infrastruc-ture such as permeable pavements
On the enhancement of vehicle handling and energy efficiency of electric vehicles with multiple motors: the iCOMPOSE project
Electric vehicles with multiple motors allow torque-vectoring, i.e., the individual control of each powertrain torque. Torque-vectoring (TV) can provide: i) enhancement of vehicle safety and handling, via the generation of a
direct yaw moment to shape the understeer characteristics and increase yaw and sideslip damping; and ii) energy consumption reductions, via appropriate torque
allocation to each motor. The FP7 European project iCOMPOSE thoroughly addressed i) and ii). Theoretical analyses were carried out to design state-of-the art TV controllers, which were validated through: a) vehicle simulations; and b)
extensive experimental tests, which were performed at rolling road facilities and proving grounds, using a Range Rover Evoque prototype equipped with four identical on-board electric powertrains. This paper provides an overview of the TV-related contributions of iCOMPOSE
Design, analysis and investigation of an independent suspension for passenger cars
The objective of this paper is the design of a front suspension. The layout used is the McPherson strut, widely adopted for road cars due to its simplicity and to the limited space required. The handling, comfort and durability of the suspension are strictly related to the position of the hardpoints, and to the elastic elements. A sensitivity analysis is carried out to investigate the roll behavior of a standard vehicle during cornering. A multi-body dynamics software is used to perform ramp-steer simulations on a full-vehicle model. Results show the different peculiarities of three specific cases of analysis, each of them emphasising the effects of a specific parameter on the whole system
pGlu-serpinin protects the normotensive and hypertensive heart from ischemic injury
Serpinin peptides derive from proteolytic cleavage of Chromogranin-A at C-terminus. Serpinin and the more potent pyroglutaminated-Serpinin (pGlu-Serp) are positive cardiac beta-adrenergic-like modulators, acting through β1-AR/AC/cAMP/PKA pathway. Since in some conditions this pathway and/or other pro-survival pathways, activated by other Chromogranin-A fragments, may cross-talk and may be protective, here we explored whether pGlu-Serp cardioprotects against ischemia/reperfusion injury under normotensive and hypertensive conditions. In the latter condition cardioprotection is often blunted because of the limitations on pro-survival Reperfusion-Injury-Salvage-Kinases (RISK) pathway activation. The effects of pGlu-Serp were evaluated on infarct size (IS) and cardiac function by using the isolated and Langendorff perfused heart of normotensive (WKY) and spontaneously hypertensive (SHR) rats exposed to ischemic pre-conditioning (PreC) and post-conditioning (PostC). In both WKY and SHR rat, pGlu-Serp induced mild cardioprotection in both PreC and in PostC. pGlu-Serp administered at the reperfusion (Serp-PostC) significantly reduced IS, being more protective in SHR than in WKY. Conversely, developed Left Ventricular Pressure (LVDevP) post-ischemic recovery was greater in WKY than in SHR. pGlu-Serp-PostC reduced contracture in both strains. Co-infusion with specific RISK inhibitors (PI3K/AkT, MitoK(ATP) channels, and PKC) blocked the pGlu-Serp-PostC protective effects. To show direct effect on cardiomyocytes, we pre-treated H9c2 with pGlu-Serp which were thus protected against hypoxia/reoxygenation. These results suggest pGlu-Serp as a potential modulatory agent implicated in the protective processes which can limit infarct size and overcome the hypertension-induced failure of PostC
Immediate-early gene expression in human saphenous veins harvested during coronary artery bypass graft operations
Saphenous vein graft occlusion is a common late complication of coronary bypass grafting. Intimal smooth muscle cell hyperplasia is a component of this pathobiology, but the underlying molecular events are poorly understood. Immediate-early genes are activated shortly after growth stimulation and subserve cellular functions, which may contribute to intimal smooth muscle cell accumulation. In the present study, human saphenous vein grafts were harvested with minimal manipulation during coronary bypass and processed for isolation of total ribonucleic acid to examine changes in immediate-early gene expression of messenger ribonucleic acid by Northern blotting techniques. Thirty saphenous vein grafts were incubated at 4° C in Dulbecco's modified Eagle media from 30 minutes to 10 hours. The messenger ribonucleic acids for immediate-early genes c-fos and c-myc were weak or undetectable in controls but were increased (>10 times controls) within 1 hour (c-fos) and persisted for at least 6 hours (c-myc) after harvest. Our results demonstrate, for the first time in human vascular tissue, incipient immediate-early gene induction. This information may lead to molecular therapies to control saphenous vein graft disease
Catestatin Reduces Myocardial Ischaemia/Reperfusion Injury: Involvement of PI3K/Akt, PKCs, Mitochondrial KATP Channels and ROS Signalling.
Vehicle sideslip estimation for four-wheel-steering vehicles using a particle filter
The availability of the most relevant vehicle states is crucial for the development of advanced vehicle control systems and driver assistance systems. Specifically the vehicle sideslip angle plays a key role, yet this state is unpractical to measure and still not straightforward to estimate. This paper investigates a particle filter approach to estimate the chassis sideslip angle of road vehicles. The filter relies on a physical model of the vehicle and on measurements available from cheap and widespread sensors including inertial measurement unit and steering wheel angle sensor(s). The approach is validated using experimental data collected with the research platform RoboMobil (RoMo), a by-wire electric vehicle with wheel-individual traction and steering actuators. Results show that the performance of the proposed particle filter is satisfactory, and indicate directions for further improvement
Catestatin Increases the Expression of Anti-Apoptotic and Pro-Angiogenetic Factors in the Post-Ischemic Hypertrophied Heart of SHR.
BACKGROUND:In the presence of comorbidities the effectiveness of many cardioprotective strategies is blunted. The goal of this study was to assess in a hypertensive rat model if the early reperfusion with anti-hypertensive and pro-angiogenic Chromogranin A-derived peptide, Catestatin (CST:hCgA352-372; CST-Post), protects the heart via Reperfusion-Injury-Salvage-Kinases (RISK)-pathway activation, limiting infarct-size and apoptosis, and promoting angiogenetic factors (e.g., hypoxia inducible factor, HIF-1α, and endothelial nitric oxide synthase, eNOS, expression). METHODS AND RESULTS:The effects of CST-Post on infarct-size, apoptosis and pro-angiogenetic factors were studied in isolated hearts of spontaneously hypertensive rats (SHR), which underwent the following protocols: (a) 30-min ischemia and 120-min reperfusion (I/R); (b) 30-min ischemia and 20-min reperfusion (I/R-short), both with and without CST-Post (75 nM for 20-min at the beginning of reperfusion). In unprotected Wistar-Kyoto hearts, used as normal counterpart, infarct-size resulted smaller than in SHR. CST-Post reduced significantly infarct-size and improved post-ischemic cardiac function in both strains. After 20-min reperfusion, CST-Post induced S-nitrosylation of calcium channels and phosphorylation of RISK-pathway in WKY and SHR hearts. Yet specific inhibitors of the RISK pathway blocked the CST-Post protective effects against infarct in the 120-min reperfusion groups. Moreover, apoptosis (evaluated by TUNEL, ARC and cleaved caspase) was reduced by CST-Post. Importantly, CST-Post increased expression of pro-angiogenetic factors (i.e., HIF-1α and eNOS expression) after two-hour reperfusion. CONCLUSIONS:CST-Post limits reperfusion damages and reverses the hypertension-induced increase of I/R susceptibility. Moreover, CST-Post triggers antiapoptotic and pro-angiogenetic factors suggesting that CST-Post can be used as an anti-maladaptive remodeling treatment
Renewing Criminalized and Hegemonic Cultural Landscapes
The Mafia's long historical pedigree in Mezzogiorno, Southern Italy, has empowered the Mafioso as a notorious, uncontested, and hegemonic figure. The counter-cultural resistance against the mafiosi culture began to be institutionalized in the early 1990s. Today, Libera Terra is the largest civil society organization in the country that uses the lands confiscated from the Mafia as a space of cultural repertoire to realize its ideals. Deploying labor force through volunteer participation, producing biological fruits and vegetables, and providing information to the students on the fields are the principal cultural practices of this struggle. The confiscated lands make the Italian experience of anti-Mafia resistance a unique example by connecting the land with the ideals of cultural change. The sociocultural resistance of Libera Terra conveys a political message through these practices and utters that the Mafia is not invincible. This study draws the complex panorama of the Mafia and anti-Mafia movement that uses the ‘confiscated lands’ as cultural and public spaces for resistance and socio-cultural change. In doing so, this article sheds new light on the relationship between rural criminology and crime prevention policies in Southern Italy by demonstrating how community development practice of Libera Terra changes the meaning of landscape through iconographic symbolism and ethnographic performance
On the dynamic analysis of a novel snake robot: preliminary results
In recent years, modular robotics has become of great interest in the robotics community. Among them, snake robots are among the most flexible and versatile type of mobile robots, well-suited to a large number of applications, such as exploration and inspection tasks, participation to search and rescue missions etc. The present paper investigates the design of a novel snake robot, named Rese_Q01, currently being designed at Politecnico di Torino. In order to characterise the dynamic behaviour of the robot, a simple vehicle dynamics model is developed and basic simulations are carried out for a first implementation of a unit consisting of two modules. Preliminary results show the influence of the robot velocity on the trajectory curvature radius, as well as the effect of different ground/tire friction conditions. This analysis is the first step in order to develop effective control strategies for robot trajectories
- …