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

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

Levantamento de hospedeiros e parasitóides de Anastrepha spp. (Diptera: Tephritidae) no município de Boa Vista, Estado de Roraima.

Resumo 937-1

Detection of Parechovirus (P) and Enterovirus (E) Among Infants Evaluated for Late-Onset Sepsis in the Neonatal Intensive Care Unit (NICU): The VIRIoN-P-E Study

Background: Limited data exist on the role of human parechoviruses (HPeV) and enteroviruses (EV) as causes of late-onset sepsis (LOS) in the NICU. Objective: To determine the frequency of detection of parechoviruses and enteroviruses among infants >72 hr of age who were evaluated for LOS in 2 academic NICUs (Parkland Memorial Hospital [PMH], Dallas -shared bays; Women & Infants Hospital [W&I], RI -single patient rooms) Design/Methods: Prospective cohort study of inborn infants hospitalized in the NICU at PMH and WIH from 1/2012 to 1/2013 and were enrolled in the Viral Respiratory Infections in the Neonatal Intensive Care Unit (VIRIoN-I; J Pediatr 2014:165:690). Eligible subjects were infants of all gestational ages (GA) and birth weights (BW) who were >72 hrs of age, remained in the NICU since birth, and underwent evaluation with initiation of antibiotic therapy for suspected LOS. Nasopharyngeal specimens were obtained within 72 hrs of the sepsis evaluation using flexible flocked nylon swabs that were placed in universal transport medium and frozen at -80\ub0C until tested for parechovirus and enterovirus RNA by polymerase chain reaction (PCR) assay (Virology Laboratory, Nationwide Children\u2019s Hospital, Columbus, OH). Demographic, clinical, laboratory, and radiographic data were obtained. Results: Of the 100 infants enrolled in the VIRIoN-I study, nasopharyngeal specimens were available from 65 (59, PMH; 6, WIH) for parechovirus and enterovirus PCR testing. These 65 infants (38, male; 27, female; 49, Hispanic; 6, white; 9, Black; 1, unknown) had a mean \ub1SD gestational age of 30 \ub1 5 wks and birth weight of 1619 \ub1 929 g, and received empirical antibiotics for possible LOS. Infants had a total of 94 sepsis evaluations (65, 1 evaluation; 16, 2; 8, 3; 4, 4) at a mean age of 20 days. Reasons for the sepsis evaluations included fever (9), hypothermia (65), apnea (50),feeding intolerance (51), seizure (1), irritabilitiy (5), emesis (20), diarrhea (1), bloody stool (5), rhinorrhea/congestion/cough (6), and lethargy (9). Four infants died. None of the infants had parechovirus or enterovirus detected in nasopharygeal specimens either at the first or subsequent sepsis evaluations. Conclusion(s): The burden of disease due to parechovirus and enteroviruses among inborn infants who remain in the NICU since birth appears to be low in those evaluated for LOS. Larger, prospective studies are needed to fully determine their contribution to \u201cculture-negative\u201d sepsis in the NICU. Publication Number: 3860.53

Fenologia da goiabeira 'Paluma' sob diferentes sistemas de cultivos, épocas e intensidades de poda de frutificação.

O trabalho teve como objetivo avaliar os efeitos de diferentes épocas e intensidades de poda de frutificação sobre a fenologia da goiabeira 'Paluma', em dois sistemas de cultivo, em Pedro Canário (ES). O delineamento experimental foi o de blocos ao acaso, em esquema de parcelas sub-subdivididas. As parcelas foram os sistemas de cultivo irrigado e sequeiro; as subparcelas foram as épocas de poda (10/11/2005, 9/12/2005, 13/1/2006 e 10/2/2006); e as sub-subparcelas foram as intensidades de poda (curta, média e longa). O ciclo da goiabeira 'Paluma', entre a poda até o início da colheita dos frutos, variou de 182 (poda em novembro e dezembro) a 203 dias (poda em fevereiro). A queda fisiológica dos frutos ocorreu até os 56 dias após o final do florescimento. A irrigação e a poda longa proporcionaram maior brotação e estabelecimento dos ramos. As plantas submetidas à poda longa em fevereiro produziram maior número de frutos por ramo. Independentemente da época de poda, as plantas submetidas à poda curta apresentaram menor número de frutos por ramo e menor índice de pegamento de frutos. A irrigação e as podas realizadas em dezembro e janeiro favoreceram a produção de frutos maiores

Origin of atomic clusters during ion sputtering

Previous studies have shown that the size distributions of small clusters ( n<=40 n = number of atoms/cluster) generated by sputtering obey an inverse power law with an exponent between -8 and -4. Here we report electron microscopy studies of the size distributions of larger clusters ( n>=500) sputtered by high-energy ion impacts. These new measurements also yield an inverse power law, but one with an exponent of -2 and one independent of sputtering yield, indicating that the large clusters are produced when shock waves, generated by subsurface displacement cascades, ablate the surface

Management of the mother-infant dyad with suspected or confirmed SARS-CoV-2 infection in a highly epidemic context

In the context of SARS-CoV-2 pandemic, the hospital management of mother-infant pairs poses to obstetricians and neonatologists previously unmet challenges. In Lombardy, Northern Italy, 59 maternity wards networked to organise the medical assistance of mothers and neonates with suspected or confirmed SARS-CoV-2 infection. Six "COVID-19 maternity centres" were identified, the architecture and activity of obstetric and neonatal wards of each centre was reorganised, and common assistance protocols for the management of suspected and proven cases were formulated. Here, we present the key features of this reorganization effort, and our current management of the mother-infant dyad before and after birth, including our approach to rooming-in practice, breastfeeding and neonatal follow-up, based on the currently available scientific evidence. Considered the rapid diffusion of COVID-19 all over the world, we believe that preparedness is fundamental to assist mother-infant dyads, minimising the risk of propagation of the infection through maternity and neonatal wards

Anastrepha species (Diptera: Tephritidae), their hosts and parasitoids in the extreme north of Brazil.

O presente trabalho foi realizado em cinco municípios do Estado de Roraima, Brasil, com o objetivo de registrar a ocorrência de espécies de Anastrepha, suas plantas hospedeiras e parasitoides. Foram coletados frutos carnosos de 21 espécies pertencentes a 10 famílias botânicas de setembro/2007 a setembro/2008. Foram identificadas 10 espécies de Anastrepha (Anastrepha bahiensis Lima e Anastrepha montei Lima foram registradas pela primeira vez em Roraima) e cinco espécies de parasitoides (4 Braconidae e 1 Figitidae). Doryctobracon areolatus (Szépligeti) foi o parasitoide mais abundante