Solar Wind Speed Estimate with Machine Learning Ensemble Models for LISA

In this work we study the potentialities of machine learning models in reconstructing the solar wind speed observations gathered in the first Lagrangian point by the ACE satellite in 2016--2017 using as input data galactic cosmic-ray flux variations measured with particle detectors hosted onboard the LISA Pathfinder mission also orbiting around L1 during the same years. We show that ensemble models composed of heterogeneous weak regressors are able to outperform weak regressors in terms of predictive accuracy. Machine learning and other powerful predictive algorithms open a window on the possibility of substituting dedicated instrumentation with software models acting as surrogates for diagnostics of space missions such as LISA and space weather science.Comment: Submitted to Environmental Modelling & Softwar

First record in Cyprus of Cinara (Cinara) cedri Mimeur (Aphididae Lachninae) on Cedrus brevifolia (Hooker fil.) Henry.

The Authors report on the discovery in South Cyprus of the aphid Cinara (Cinara) cedri Mimeur collected on the endemic cedar, Cedrus brevifolia (Hooker fil.) Henry. This is the first record of the lacnid in Cyprus. The ecological aspects of the cedar and its interaction with the related aphid species are discussed. The Authors suggest the hypothesis that the aphid may be co-endemic with its host conifer since it shows significant morphological differences compared with specimens from other European regions. The question whether the Cyprus cedar aphid can be injurious or not to its host plant is debated as well. The exact taxonomic position of this lacnid is currently under investigation

Hypercube-Based Methods for Symbolic Knowledge Extraction: Towards a Unified Model

Symbolic knowledge-extraction (SKE) algorithms proposed by the XAI community to obtain human-intelligible explanations for opaque machine learning predictors are currently being studied and developed with growing interest, also in order to achieve believability in interactions. However, choosing the most adequate extraction procedure amongst the many existing in the literature is becoming more and more challenging, as the amount of available methods increases. In fact, most of the proposed algorithms come with constraints over their applicability. In this paper we focus upon a quite general class of SKE techniques, namely hypercube-based methods. Despite being commonly considered regression-specific, we discuss why hypercube-based SKE methods are flexible enough to deal with classification problems as well. More generally, we propose a common generalised model for hypercube-based methods, and we show how they can be exploited to perform SKE on datasets, predictors, or learning tasks of any sort. We also report as a concrete example the implementation of the proposed generalisation in the PSyKE framework

Towards a unified model for symbolic knowledge extraction with hypercube-based methods

The XAI community is currently studying and developing symbolic knowledge-extraction (SKE) algorithms as a means to produce human-intelligible explanations for black-box machine learning predictors, so as to achieve believability in human-machine interaction. However, many extraction procedures exist in the literature, and choosing the most adequate one is increasingly cumbersome, as novel methods keep on emerging. Challenges arise from the fact that SKE algorithms are commonly defined based on theoretical assumptions that typically hinder practical applicability. This paper focuses on hypercube-based SKE methods, a quite general class of extraction techniques mostly devoted to regression-specific tasks. We first show that hypercube-based methods are flexible enough to support classification problems as well, then we propose a general model for them, and discuss how they support SKE on datasets, predictors, or learning tasks of any sort. Empirical examples are reported as well – based upon the PSyKE framework –, showing the applicability of hypercube-based methods to actual classification tasks

Bridging the gap between Monte Carlo simulations and measurements of the LISA Pathfinder test-mass charging for LISA

Cubic gold-platinum free-falling test masses (TMs) constitute the mirrors of future LISA and LISA-like interferometers for low-frequency gravitational wave detection in space. High-energy particles of Galactic and solar origin charge the TMs and thus induce spurious electrostatic and magnetic forces that limit the sensitivity of these interferometers. Prelaunch Monte Carlo simulations of the TM charging were carried out for the LISA Pathfinder (LPF) mission, that was planned to test the LISA instrumentation. Measurements and simulations were compared during the mission operations. The measured net TM charging agreed with simulation estimates, while the charging noise was three to four times higher. We aim to bridge the gap between LPF TM charging noise simulations and observations. New Monte Carlo simulations of the LPF TM charging due to both Galactic and solar particles were carried out with the FLUKA/LEI toolkit. This allowed propagating low-energy electrons down to a few electronvolt. These improved FLUKA/LEI simulations agree with observations gathered during the mission operations within statistical and Monte Carlo errors. The charging noise induced by Galactic cosmic rays is about one thousand charges per second. This value increases to tens of thousands charges per second during solar energetic particle events. Similar results are expected for the LISA TM charging.Comment: 11 pages, 9 figure

Anoplophora chinensis (Forster) (Coleoptera Cerambycidae) in the outbreak site in Rome (Italy): experiences in dating exit holes

Anoplophora chinensis is a poliphagous woodboring beetle native to Eastern Asia, and is a serious pest accidentally introduced into Europe. Currently two infested areas are present in Italy and other infestations have occurred in the past in other European countries, while interceptions in entry ports are made yearly by National Plant Protection Organizations of the European Community. A. chinensis is a quarantine invasive pest, and strong measures are applied worldwide to prevent its introduction, spread and to eradicate its populations. The presence of exit holes of adult beetles on infested trees is one of the most important diagnostic signs to detect an A. chinensis infestation. Exit holes are visible on the bark surface of infested trees for several years, but the hole is after that enclosed by the reaction tissue (callus) of the plant; thus, after some years the exit hole is no longer visible. Such injuries produced by beetle activity can be recognised after many years by inspection of the wood after cross-sectioning of the tree. It is possible to date the time of occurrence of the injury using the annual growth ring method for tree age analyses. Surveys conducted on the wooden material collected in the infested site in Rome indicate that the first A. chinensis adult emergences from infested trees of the city occurred in 2002. Since the species takes in the infested site 1 or 2 years for juvenile development, we can speculate that the first introduction of A. chinensis into the city of Rome took place in the years 2000 or 2001

Gamasid soil mites (Arachnida Acari) as indicators of the conservation status of forests

The Gamasida of 8 study areas in 5 different Sites of Community Interest (SCI of the Nature 2000 network) of Central Italy, characterized by beech forest and by mixed forests, were investigated to collect information for define the conservation status of the investigated sites. Samples were taken in autumn from the forest ground of the study sites (litter and soil till 7 cm in depth) during the three years of the study. Collected adult specimens were identified at species level and data were used to calculate the following indices: Shannon, Simpson, Eveness and Maturity index. On the whole, in the 8 study sites were recorded 63 species of Gamasida, belonging to 17 families, and some species seems to be a rare component of the fauna. Among study sites, diversity indices ranged from 2.20 to 2.57 for the Shannon index and from 0.82 to 0.90 for the Simpson, while the Maturity index ranged from 0.69 to 0.85; no substantial differences were observed among different study areas

Recurrent galactic cosmic-ray flux modulation in L1 and geomagnetic activity during the declining phase of the solar cycle 24

Galactic cosmic-ray (GCR) flux short-term variations ($<$1 month) in the inner heliosphere are mainly associated with the passage of high-speed solar wind streams (HSS) and interplanetary (IP) counterparts of coronal mass ejections (ICMEs). Data gathered with a particle detector flown on board the ESA LISA Pathfinder (LPF) spacecraft, during the declining part of the solar cycle 24 (February 2016 - July 2017) around the Lagrange point L1, have allowed to study the characteristics of recurrent cosmic-ray flux modulations above 70 MeV n$^{-1}$. %These modulations are observed when the solar wind speed is $>$ 400 km s$^{-1}$ and/or the IP magnetic field intensity $>$ 10 nT. It is shown that the amplitude and evolution of individual modulations depend in a unique way on both IP plasma parameters and particle flux intensity before HSS and ICMEs transit. By comparing the LPF data with those gathered contemporaneously with the magnetic spectrometer experiment AMS-02 on board the International Space Station and with those of Earth polar neutron monitors, the GCR flux modulation was studied at different energies during recurrent short-term variations. It is also aimed to set the near real-time particle observation requirements to disentangle the role of long and short-term variations of the GCR flux to evaluate the performance of high-sensitivity instruments in space such as the future interferometers for gravitational wave detection. Finally, the association between recurrent GCR flux variation observations in L1 and weak to moderate geomagnetic activity in 2016-2017 is discussed. Short-term recurrent GCR flux variations are good proxies of recurrent geomagnetic activity when the B$_z$ component of the IP magnetic field is directed northern

A RANDOMIZED, DOUBLE-BLIND, CROSS-OVER STUDY COMPARING A LEVOSULPIRIDE-BASED AND A METOCLOPRAMIDE-BASED COMBINATION IN THE PREVENTION OF PROMECE-CYTABOM-INDUCED EMESIS

Background. To test two different antiemetic regimens for preventing nausea and vomiting in patients with non-Hodgkin's lymphoma (NHL) undergoing systemic chemotherapy (CT) with ProMECE-CytaBOM (P-C). Patients and Methods. Twenty consecutive untreated adult outpatients with histologically confirmed NHL and scheduled to receive P-C chemotherapy were registered in a randomized, double-blind, cross-over study to compare the antiemetic efficacy of a levosulpiride (LS)-based and metoclopramide (MTC)-based regimen. Results. Complete protection from vomiting was recorded in 93% (62/67) of courses with the LS-regimen and in 89% (62/70) with the MTC-regimen (p = 0.428). No nausea was observed in 84% (56/67) of courses with the LS-regimen and in 74% (52/70) with the MTC-regimen (p = 0.183). No differences in prevention of emesis were recorded when patients crossed to the other regimen. Both regimens were well tolerated; however, on day 8 of chemotherapy, when both antiemetic regimens were administered at a higher dose, the LS-based combination showed significantly lower toxicity (p = 0.035). Conclusions. ProMECE-CytaBOM-induced emesis can be prevented in most cases with appropriate, specifically designed antiemetic therapy. Both the LS- and MTC-based combinations resulted in a high percentage of complete protection from emesis, but the higher incidence of side effects observed with MTC makes the LS-based regimen preferable for patients receiving P-C chemotherapy

SEARCHING FOR NATIVE EGG-PARASITOIDS OF THE INVASIVE ALIEN SPECIES HALYOMORPHA HALYS STÅL (HETEROPTERA PENTATOMIDAE) IN SOUTHERN EUROPE

Halyomorpha halys is an invasive species, originating from East Asia, which was accidentally introduced in some areas of North America and Europe, where severe damages to different vegetable crops and fruit plants were recorded. Several studies in different countries focused on the possibility to apply biological control by means of egg- parasitoids. The main egg-parasitoids in the original area are unfortunately non-specific and thus the application of classical biological control is questionable. On the other hand, the possibility of using augmentative biological control by native egg-parasitoids able to exploit the new host is an interesting possibility in both Europe and the USA. In a preliminary assay, frozen egg masses of H. halys were exposed in the field in Central Italy. Results showed that some eggs were exploited by parasitoids belonging to the species Anastatus bifasciatus and Ooencyrtus telenomicida. Therefore, different native egg-parasitoids species widespread in Europe were tested in the laboratory in order to explore their ability to parasitize H. halys eggs. To this end, no-choice tests were carried out in climatic chambers (26°C, 70%RH, 16:8 L:D) in order to evaluate the parasitization potential of females collected in the wild. Conducted tests pointed out that A. bifasciatus and especially O. telenomicida may be potential candidates for the biological control of H. halys. In particular, O. telenomicida was able to parasitize the 35.56% of the exposed host eggs in the lab tests. New adults successfully emerged from the 22.92% of the eggs, and on the whole, this egg-parasitoid caused a significant hatching reduction of the H. halys eggs (more than 70%). Conversely, Telenomus chloropus and Ooencyrtus pityocampae were less promising species as biocontrol agents of this agricultural pest. Preliminary trials in pear orchards consisting of field releases of laboratory-reared specimens of O. telenomicida, one of the potential candidates for biological control, showed that this parasitoid is actually able to discover egg masses of H. halys (sentinel frozen egg masses) and to successfully parasitize them