Simulations of secondary Farley-Buneman instability driven by a kilometer-scale primary wave: anomalous transport and formation of flat-topped electric fields

Since the 1950s, high frequency and very high frequency radars near the magnetic equator have frequently detected strong echoes caused ultimately by the Farley‐Buneman instability (FBI) and the gradient drift instability (GDI). In the 1980s, coordinated rocket and radar campaigns made the astonishing observation of flat‐topped electric fields coincident with both meter‐scale irregularities and the passage of kilometer‐scale waves. The GDI in the daytime E region produces kilometer‐scale primary waves with polarization electric fields large enough to drive meter‐scale secondary FBI waves. The meter‐scale waves propagate nearly vertically along the large‐scale troughs and crests and act as VHF tracers for the large‐scale dynamics. This work presents a set of hybrid numerical simulations of secondary FBIs, driven by a primary kilometer‐scale GDI‐like wave. Meter‐scale density irregularities develop in the crest and trough of the kilometer‐scale wave, where the total electric field exceeds the FBI threshold, and propagate at an angle near the direction of total Hall drift determined by the combined electric fields. The meter‐scale irregularities transport plasma across the magnetic field, producing flat‐topped electric fields similar to those observed in rocket data and reducing the large‐scale wave electric field to just above the FBI threshold value. The self‐consistent reduction in driving electric field helps explain why echoes from the FBI propagate near the plasma acoustic speed.NSF grants PHY-1500439 and AGS-1755350 and NASA grant NNX14AI13G supported the research presented in this work. This work used TACC and XSEDE computational resources supported by the National Science Foundation grant ACI-1053575. This paper did not use any data; simulation runs are archived on the TACC Ranch system. The authors thank one anonymous reviewer for helpful comments. (PHY-1500439 - NSF; AGS-1755350 - NSF; NNX14AI13G - NASA; ACI-1053575 - National Science Foundation)Published version2019-07-0

A hierarchical autonomous driver for a racing car: Real-time planning and tracking of the trajectory

The aim of this study was to develop trajectory planning that would allow an autonomous racing car to be driven as close as possible to what a driver would do, defining the most appropriate inputs for the current scenario. The search for the optimal trajectory in terms of lap time reduction involves the modeling of all the non-linearities of the vehicle dynamics with the disadvantage of being a time-consuming problem and not being able to be implemented in real-time. However, to improve the vehicle performances, the trajectory needs to be optimized online with the knowledge of the actual vehicle dynamics and path conditions. Therefore, this study involved the development of an architecture that allows an autonomous racing car to have an optimal online trajectory planning and path tracking ensuring professional driver performances. The real-time trajectory optimization can also ensure a possible future implementation in the urban area where obstacles and dynamic scenarios could be faced. It was chosen to implement a local trajectory planning based on the Model Predictive Control(MPC) logic and solved as Linear Programming (LP) by Sequential Convex Programming (SCP). The idea was to achieve a computational cost, 0.1 s, using a point mass vehicle model constrained by experimental definition and approximation of the car’s GG-V, and developing an optimum model-based path tracking to define the driver model that allows A car to follow the trajectory defined by the planner ensuring a signal input every 0.001 s. To validate the algorithm, two types of tests were carried out: a Matlab-Simulink, Vi-Grade co-simulation test, comparing the proposed algorithm with the performance of an offline motion planning, and a real-time simulator test, comparing the proposed algorithm with the performance of a professional driver. The results obtained showed that the computational cost of the optimization algorithm developed is below the limit of 0.1 s, and the architecture showed a reduction of the lap time of about 1 s compared to the offline optimizer and reproducibility of the performance obtained by the driver

Implementation of the Water Framework Directive in Italy: state of the art and selected research issues

The Water Framework Directive (WFD) was implemented rather late in Italy. The actual implementation took place in 2006 with decree 152/2006 but the Directive was not completely effective until the beginning of 2009, when law 13/2009 provided for the implementation of river basin plans by basin authorities. The objective of this paper is to describe the implementation of the WFD in Italy and to discuss selected policy and research issues. The paper begins with an introduction highlighting the specificities of Italy in terms of water management. With regard to implementation, the general administrative setting, as well as the interpretation of WFD categories related to economic evaluations will be illustrated. Two major issues of particularly high relevance in the present debate are then discussed: a) the evaluation of environmental and resource costs; and b) water regulation in agriculture.Department of Agricultural Economics and Engineering, University of Bologna (Italy). Department of Statistics, University of Bologna (Italy)

Interpreting physical and mental metaphors: Is Theory of Mind associated with pragmatics in middle childhood?

We investigated the association between individual differences in metaphor understanding and Theory of Mind (ToM) in typically developing children. We distinguished between two types of metaphors and created a Physical and Mental Metaphors task, echoing a similar distinction for ToM. Nine-year-olds scored lower than older age-groups in ToM as well as in the interpretation of mental, but not physical, metaphors. Moreover, nine-year-olds (but not older children) who are better in ToM are also better in interpreting mental, but not physical, metaphors. This suggests that the link between metaphor and ToM is stronger when metaphorical interpretation involves mental aspects, and it is more evident in early rather than later childhood

Ocorrência de Anastrepha zenildae Zucchi (Diptera: Tephritidae) e seu parasitóide em frutos de Ziziphus mauritiana (Rhamnaceae) em Roraima.

Resumo 1626-1

Continuous product innovation : a comparison of key elements across different contingency sets

This paper discusses results from an international study of continuous improvement in product innovation. The empirical research is based upon a theoretical model of continuous product innovation (CPI) that identifies contingencies, behaviours, levers and performances relevant to improving product innovation processes. As successful knowledge management is widely recognised as a key capability for firms to successfully develop CPI, companies have been classified according to identified contingencies and the impact of these contingencies on key knowledge management criteria. Comparative analysis of the identified groups of companies has demonstrated important differences between the learning behaviours found present in the two groups thus identified, and in the levers used to develop and support these behaviours. The selection of performance measures by the two groups has highlighted further significant differences in the way the two groups understand and measure their CPI processes. Finally, the paper includes a discussion of appropriate mechanisms for firms with similar contingency sets to improve their approaches to organisational learning and product innovation

Effect of temperature increase during the tableting of pharmaceutical materials

Scale-up of tableting process is particularly difficult due to specific concerns related exclusively to the process itself and that cannot be determined on a smaller scale, which are the effect of compression speed and the build-up of heat due to the length of the compaction operations. In this work, it has been simulated the rise of temperature observed during the tablets manufacturing in a full production scale by means of an appropriate modification of a R&D rotary tablet machine. Four common pharmaceutical excipients, characterized by different chemical nature, consolidation behaviour and temperature sensitiveness have been analysed in terms of compaction mechanism (Heckel and energy analysis) and tabletability, in order to verify any effect of the increase of temperature. The results showed a relevance of the temperature on mechanical tablets properties only on materials characterized by low temperature thermal transitions (melting or glass transition), while, for compounds which do not exhibit thermal events at low temperature, it becomes less important for ductile materials and irrelevant for brittle materials. Heckel analysis highlighted a noticeable increase of ductility only in those materials whose tablets mechanical properties depended on the temperature. On the other hand, energy analysis showed low sensitivity failing to identify any temperature effect on compaction materials properties. This work showed how to simulate the process of temperature rise on a small scale and the influence of temperature on materials compaction properties. The use of a modified tableting machine, able to control the temperature and moisture levels and also capable of monitoring the punch movements, resulted in identifying the effect of temperature both on mechanical and compaction properties on materials. Thus, it represents a valuable tool in order to provide useful information at an early stage during the development of tablets formulations

Heat shock induced changes of adipokines gene expression in 3T3-L1 adipocytes

To study the effects of heat shock on adipokines gene expression 3T3-L1 adipocytes were used. Heat shock differently affected gene expression of leptin, adiponectin and acylation stimulating protein (ASP): exposure of cells to temperature higher than 39°C caused upregulation of leptin and downregulation of adiponectin and ASP genes. The present study provides the first evidence about the effects of heat shock on adipokines gene expression. Changes in gene expression of the three adipokines may help to explain the alteration of lipid metabolism and liver functionality occurring in animals exposed to hot conditions

Partnering for sustainability in agri-food supply chains: the case of Barilla Sustainable Farming in the Po Valley

This is the final version. Available on open access from Springer via the DOI in this recordAvailability of data and materials: Not applicableThe objective of the paper is to understand the process of designing a multi-stakeholder partnership in the adoption of sustainable innovations in value chains. More specifically, the focus is on the design of feasible types of horizontal agreements and contractual formulas to be implemented in the agri-food supply chain in order to introduce sustainable agricultural practices. To this purpose, the Barilla Sustainable Farming initiative, which is currently in the first phase of designing an MSP, is used as a case study.European Union Horizon 202

How Does SARS-CoV-2 Affect the Central Nervous System? A Working Hypothesis

Interstitial pneumonia was the first manifestation to be recognized as caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); however, in just a few weeks, it became clear that the coronavirus disease-2019 (COVID-19) overrun tissues and more body organs than just the lungs, so much so that it could be considered a systemic pathology. Several studies reported the involvement of the conjunctiva, the gut, the heart and its pace, and vascular injuries such as thromboembolic complications and Kawasaki disease in children and toddlers were also described. More recently, it was reported that in a sample of 214 SARS-CoV-2 positive patients, 36.4% complained of neurological symptoms ranging from non-specific manifestations (dizziness, headache, and seizures), to more specific symptoms such hyposmia or hypogeusia, and stroke. Older individuals, especially males with comorbidities, appear to be at the highest risk of developing such severe complications related to the Central Nervous System (CNS) involvement. Neuropsychiatric manifestations in COVID-19 appear to develop in patients with and without pre-existing neurological disorders. Growing evidence suggests that SARS-CoV-2 binds to the human Angiotensin-Converting Enzyme 2 (ACE2) for the attachment and entrance inside host cells. By describing ACE2 and the whole Renin Angiotensin Aldosterone System (RAAS) we may better understand whether specific cell types may be affected by SARS-CoV-2 and whether their functioning can be disrupted in case of an infection. Since clear evidences of neurological interest have already been shown, by clarifying the topographical distribution and density of ACE2, we will be able to speculate how SARS-CoV-2 may affect the CNS and what is the pathogenetic mechanism by which it contributes to the specific clinical manifestations of the disease. Based on such evidences, we finally hypothesize the process of SARS-CoV-2 invasion of the CNS and provide a possible explanation for the onset or the exacerbation of some common neuropsychiatric disorders in the elderly including cognitive impairment and Alzheimer disease