Retrieval of Snow Properties for Ku- and Ka-band Dual-Frequency Radar

The focus of this study is on the estimation of snow microphysical properties and the associated bulk parameters such as snow water content and water equivalent snowfall rate for Ku- and Ka-band dual-frequency radar. This is done by exploring a suitable scattering model and the proper particle size distribution (PSD) assumption that accurately represent, in the electromagnetic domain, the micro/macro-physical properties of snow. The scattering databases computed from simulated aggregates for small-to-moderate particle sizes are combined with a simple scattering model for large particle sizes to characterize snow scattering properties over the full range of particle sizes. With use of the single-scattering results, the snow retrieval lookup tables can be formed in a way that directly links the Ku- and Ka-band radar reflectivities to snow water content and equivalent snowfall rate without use of the derived PSD parameters. A sensitivity study of the retrieval results to the PSD and scattering models is performed to better understand the dual-wavelength retrieval uncertainties. To aid in the development of the Ku- and Ka-band dual-wavelength radar technique and to further evaluate its performance, self-consistency tests are conducted using measurements of the snow PSD and fall velocity acquired from the Snow Video Imager Particle Image Probe (SVIPIP) duringthe winter of 2014 at the NASA Wallops Flight Facility site in Wallops Island, Virginia

Co-offending and the persistence of violence: A dynamic analysis

This is the final version. Available from Springer via the DOI in this record. Data Availability: Due to privacy concerns, the research data supporting this publication are not publicly available.Objectives: Previous research underscores the influence of prior violent co-offending on subsequent violent behavior, linking it to a social contagion mechanism akin to the internalization of violence. However, these studies are limited by disregarding the entirety of a criminal career and overlooking diverse co-offending dynamics beyond co-offenders’ characteristics. This study examines the longitudinal impact of prior violent (solo and co-) offending on future individual-level violent behavior among Italian organized crime offenders. Methods: Leveraging criminal career data from 9819 Italian organized crime offenders, we model offending choices through a discrete-time Markov process. Subsequently, employing dynamic random-effects probit models, we quantify the influence of prior violent (solo and co-) offending on future violence, considering various confounders and unobserved individual-level effects. Results: Violence is a persistent and long-lasting behavior among organized crime offenders. Prior violent co-offending has a greater impact than prior violent solo offending on the probability of future violence. Prior violent co-offending increases the probability of future violent co-offending but does not impact the probability of future violent solo offending. Conclusions: The results show that co-offending promotes the transmission of violence but fail to support the internalization of violent behavior postulated by prior studies. We propose possible alternative mechanisms of violence transmission that operate through self-sustaining dynamics of violent co-offending within criminal groups. Although limited data on individual characteristics constrains interpretation, our results imply that violence transmission dynamics are independent from the individual characteristics of the co-offenders and more directly connected to group effects.European Union’s Horizon 202

Fluid pressurisation and earthquake propagation in the Hikurangi subduction zone

In subduction zones, seismic slip at shallow crustal depths can lead to the generation of tsunamis. Large slip displacements during tsunamogenic earthquakes are attributed to the low coseismic shear strength of the fluid-saturated and non-lithified clay-rich fault rocks. However, because of experimental challenges in confining these materials, the physical processes responsible for the coseismic reduction in fault shear strength are poorly understood. Using a novel experimental setup, we measured pore fluid pressure during simulated seismic slip in clay-rich materials sampled from the deep oceanic drilling of the Pāpaku thrust (Hikurangi subduction zone, New Zealand). Here, we show that at seismic velocity, shear-induced dilatancy is followed by pressurisation of fluids. The thermal and mechanical pressurisation of fluids, enhanced by the low permeability of the fault, reduces the energy required to propagate earthquake rupture. We suggest that fluid-saturated clay-rich sediments, occurring at shallow depth in subduction zones, can promote earthquake rupture propagation and slip because of their low permeability and tendency to pressurise when sheared at seismic slip velocities

Polaronic state and nanometer-scale phase separation in colossal magnetoresistive manganites

High resolution topographic images obtained by scanning tunneling microscope in the insulating state of Pr0.68Pb0.32MnO3 single crystals showed regular stripe-like or zigzag patterns on a width scale of 0.4 - 0.5 nm confirming a high temperature polaronic state. Spectroscopic studies revealed inhomogeneous maps of zero-bias conductance with small patches of metallic clusters on length scale of 2 - 3 nm only within a narrow temperature range close to the metal-insulator transition. The results give a direct observation of polarons in the insulating state, phase separation of nanometer-scale metallic clusters in the paramagnetic metallic state, and a homogeneous ferromagnetic state

Machine learning-driven approach for large scale decision making with the analytic hierarchy process

The Analytic Hierarchy Process (AHP) multicriteria method can be cognitively demanding for large-scale decision problems due to the requirement for the decision maker to make pairwise evaluations of all alternatives. To address this issue, this paper presents an interactive method that uses online learning to provide scalability for AHP. The proposed method involves a machine learning algorithm that learns the decision maker’s preferences through evaluations of small subsets of solutions, and guides the search for the optimal solution. The methodology was tested on four optimization problems with different surfaces to validate the results. We conducted a one factor at a time experimentation of each hyperparameter implemented, such as the number of alternatives to query the decision maker, the learner method, and the strategies for solution selection and recommendation. The results demonstrate that the model is able to learn the utility function that characterizes the decision maker in approximately 15 iterations with only a few comparisons, resulting in significant time and cognitive effort savings. The initial subset of solutions can be chosen randomly or from a cluster. The subsequent ones are recommended during the iterative process, with the best selection strategy depending on the problem type. Recommendation based solely on the smallest Euclidean or Cosine distances reveals better results on linear problems. The proposed methodology can also easily incorporate new parameters and multicriteria methods based on pairwise comparisons.This research was funded by National Funds through the FCT—Portuguese Foundation for Science and Technology, References UIDB/05256/2020 and UIDP/05256/2020

Preliminary bioassays on the susceptibility of stone fruits rootstocks to Capnodis tenebrionis (L.).

Capnodis tenebrionis (L.) (Coleoptera: Buprestidae), the so called Mediterranean flat-headed root-borer, is an economically important phytophagous pest species mainly on stone fruit trees (apricot, plum, cherry, peach and nectarine). Chemicals and Entomopathogenic nematodes are used for the control of adults and neonate larvae, respectively. Further control means are under investigations in order to have more options within Integrated Pest Control strategies. This study is aimed at investigating the susceptibility of rootstocks to the larvae of C. tenebrionis. Two bioassays were carried out during 2016 and 2017. A first bioassay was based on the evaluation of a potential antixenosis action expressed by neonate larvae infesting twigs of rootstocks (Marianna 26, Barrier, Adesoto, Mylaboran 29C, GF677, Garnem, Cab 6P, Max Ma60 and Colt). This bioassay allowed to process a high number of different rootstocks in a short time. It has a preliminary value. The second bioassay assessed the antibiosis influence of the rootstocks through the breeding of larvae (since the neonate ones) on artificial diets containing bark flour of Adesoto, Cab 6P, Colt, Garnem, GF677, Max Ma60, Montclar and 29C rootstock. The first bioassay showed that Colt, Mylaboran 29C and GF677 were the most susceptible rootstocks to larval infestation of C. tenebrionis and Max Ma60 was less favorable to the pest. Concerning the effects of the diet, larvae reared on a diet containing Montclar, Cab 6P and GF 677 bark flour had a mean daily increase of their weight higher that those reared on cortex tissues of other genotypes whereas Garnem and Colt had a lower increase

Syn-exhumation coupling of oceanic and continental units along the western edge of the alpine corsica: A review

The Alpine Corsica represents a segment of the Alpine collisional belt. In its western edge, it is characterized by the close association of continental units deformed under high-pressure metamorphic conditions (Lower Units) and oceanic units showing a metamorphism ranging from high-pressure (Schistes Lus-trés Complex) to very low-grade conditions (Upper Units). This paper provides a complete review of the relationships between the continental and oceanic units in selected five areas where the stratigraphic features, deformation history, metamorphic P-T path and tectonic setting are available for each unit. The collected data indicate that the oceanic units occur not only at the top of the continental ones, as generally proposed in the literature, but also intercalated within them. Such relationships were achieved at shallow structural level during the late stage of exhumation, when the continental units were tectonically coupled with the oceanic units which were dragged as slices from the orogenic wedge. The coupling probably occurred immediately before the transition from syn-to post-orogenic geodynamic regime that affected the whole Alpine-Apennine collisional system in the early Oligocene. After the coupling, the stack of oceanic and continental units experienced a further exhumation-related deformation before their final exposure at the surface