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Fine-grained just-in-time defect prediction aims at identifying likely defective files within new commits. Popular techniques are based on supervised learning, where machine learning algorithms are fed with historical data. One of the limitations of these techniques is concerned with the use of imbalanced data that only contain a few defective samples to enable a proper learning phase. To overcome this problem, recent work has shown that anomaly detection can be used as an alternative. With our study, we aim at assessing how anomaly detection can be employed for the problem of fine-grained just-in-time defect prediction. We conduct an empirical investigation on 32 open-source projects, designing and evaluating three anomaly detection methods for fine-grained just-in-time defect prediction. Our results do not show significant advantages that justify the benefit of anomaly detection over machine learning approaches.

Software logs are of great value in both industrial and open-source projects. Mobile analytics logging enables developers to collect logs remotely from their apps running on end user devices at the cost of recording and transmitting logs across the Internet to a centralised infrastructure. This paper makes a first step in characterising logging practices with a widely adopted mobile analytics logging library, namely Firebase Analytics. We provide an empirical evaluation of the use of Firebase Analytics in 57 open-source Android applications by studying the evolution of code-bases to understand: a) the needs-in-common that push practitioners to adopt logging practices on mobile devices, and b) the differences in the ways developers use local and remote logging. Our results indicate mobile analytics logs are less pervasive and less maintained than traditional logging code. Based on our analysis, we believe logging using mobile analytics is more user centered compared to traditional logging, where the latter is mainly used to record information for debugging purposes., Comment: 8th IEEE/ACM International Conference on Mobile Software Engineering and Systems 2021

International audience; Within the Horizon 2020 thematic network Inno4Grass (www.inno4grass.eu) grassland innovations were analysed in practice and science meetings that are participatory, multi-stakeholder discussion groups. Their outcome was summarised in 115 practice abstracts (PAs) from eight countries. PAs are short summaries for practitioners containing the most important results of the activity and the main practical recommendations. In order to investigate which are the most relevant common traits characterising the innovation process in the European agricultural practice, twenty-seven descriptors of the topics addressed in the PAs were scored for presence/absence. The results were analysed by means of a Principal Component Analysis, resulting in a fairly low proportion (31.5%) of the total variation explained by the first two components. Aspects related to regional marketing are quite closely related to Component 1. The factors ‘organic farming’ and ‘animal welfare’, as well as ‘conventional farming’ and ‘machinery and tools’, were strongly related to each other. There was no obvious pattern of the data due to the agroclimatic areas but decreases in management intensity seemed to be related to the adoption of regional marketing strategies. A certain bias might be present due to partners intentionally focusing only on a specific topic.

Code review is a widely used technique to support software quality. It is a manual activity, often subject to repetitive and tedious tasks that increase the mental load of reviewers and compromise their effectiveness. The developer-centered nature of code review can represent a bottleneck that does not scale in large systems with the consequence of com- promising firms’ profits. This challenge has led to an entire line of research on code review improvement.In this thesis, we present our results and remarks on the effectiveness of using fine- grained defect prediction in code review while investigating what are the information needs that lead a proper code review. We started reimplementing the state of the art of defect prediction to understand its replicability; then, we evaluated this model in a more realistic scenario that is typically considered. To improve defect prediction techniques, we come up with a fine-grained just-in-time defect prediction model that anticipates the prediction at commit time and reduces the granularity at the file level. After that, we explored how to improve further prediction performance by using alternative sources of information. We conducted a comprehensive investigation of code comments written by both open and closed source developers. Finally, to understand how to improve code review further, we explored from a reviewers’ perspective what is the information that reviewers need to lead a proper code review.Our findings show that the state of the art of defect prediction, when evaluated in a realistic scenario, cannot be directly used to support code review. Furthermore, we assessed that alternative sets of metrics, anticipated feedback, and fine-grained suggestions represent independent directions to improve prediction performance. Finally, we discovered that research must create intelligent tools that other than predict defects must satisfy actual reviewers’ needs, such as expert selection, splittable changes, realtime communication, and self summarization of changes.

International audience; Within the framework of the Horizon 2020 thematic network Inno4Grass (www.inno4grass.eu), 55 ‘practice & science meetings’ have been carried out using a multi-stakeholder, participatory approach, in order to bridge the gap between science and practice and deliver a comprehensive analysis of grassland innovations across eight European countries. Three project phases can be distinguished: (1) common guidelines under discussion, (2) introduction and preliminary test of the guidelines, (3) additional training on the discussion process. A structured feedback on the meetings held was provided by the organisers by means of a questionnaire, including information about duration, preparatory material, participants, discussion methods and evaluation of the meetings by the organisers. This information allows computing of mean values and distribution of the most relevant variables. Only a few of them were affected by the project phase. In particular, there was an increase in the use of farm portraits and of scientific literature over the project phases. All aspects describing the success of meetings were positively assessed. This suggests that the methodology for the conduction of the practice & science meetings within Inno4Grass was already relatively well established at the beginning of the project.

Within the framework of the Horizon 2020 thematic network Inno4Grass (www.inno4grass.eu), 55 'practice & science meetings' have been carried out using a multi-stakeholder, participatory approach, in order to bridge the gap between science and practice and deliver a comprehensive analysis of grassland innovations across eight European countries. Three project phases can be distinguished: (1) common guidelines under discussion, (2) introduction and preliminary test of the guidelines, (3) additional training on the discussion process. A structured feedback on the meetings held was provided by the organisers by means of a questionnaire, including information about duration, preparatory material, participants, discussion methods and evaluation of the meetings by the organisers. This information allows computing of mean values and distribution of the most relevant variables. Only a few of them were affected by the project phase. In particular, there was an increase in the use of farm portraits and of scientific literature over the project phases. All aspects describing the success of meetings were positively assessed. This suggests that the methodology for the conduction of the practice & science meetings within Inno4Grass was already relatively well established at the beginning of the project.

Salmonella and Listeria spp. are frequently detected in poultry meats. Conventional isolation and identification methods to detect these microrganisms in food are laborious and time-consuming. In the present study the occurrence of Salmonellae and Listeriae on 362 samples of retail poultry in Caserta, South Italy was evaluated and standard microbiological and rapid methods were compared. Furthermore, the samples were collected and analyzed twice a week, on Monday and Friday to establish their possible variability from storage. Both methods showed a strong contamination of samples by Listeria spp. (about 50% for both methods) with 12% Listeria monocytogenes while the contamination of Salmonella was poorer (14-15%). The two procedures showed a good agreement for the detection of Listeriae while the sensitivity of the Rapid test for Salmonellae was poorer (75%). Data about sampling on Monday and Friday highlighted a significant increase in Listeria spp. at the end of the week., Journal of Preventive Medicine and Hygiene, Vol 48, No 2 (2007)

Pharmaceuticals may reach the environment to variable extent and generally occur in low concentrations (ng-μg/L). Biotic and/or abiotic processes may also degrade these substances and no complete information exist about the environmental fate of these compounds and their possible interactions with non-target organisms. It is unlikely to have concentrations causing acute toxicity but, often, pharmaceuticals and their derivatives act chronically at concentrations that determine different sub-lethal effects in organisms exposed, from microbial communities to the higher organisms in the food chain. The current study assessed the environmental effects of some among the most prescribed drugs for chronico-degenerative diseases: furosemide (diuretic agent), atenolol (β-blocker), fibrates as bezafibrate, fenofibrate and gemfibrozil (lipid regulators). The research was enlarged to their photoproducts obtained from solar simulator irradiation of parent compounds in aqueous medium. The study started from the evaluation of the acute and chronic toxicity to calculate the toxic ratios of these drugs on different organisms of the aquatic chain and continued detecting their potential genotoxic activity. Genotoxicity was determined using the SOS Chromotest, a quantitative bacterial colorimetric assay on Escherichia coli and the Ames test on Salmonella typhimurium, the widely used short-term test for monitoring water samples. The former is currently used to detect DNA-damaging agents that activate the SOS repair system the latter to reveal point mutations. Because of same chemicals may produce different responses in different species the range of tests also included the Trad-MCN assay with young inflorescences of the plant Tradescantia paludosa and the alkaline Comet assay using human peripheral blood leukocytes. The Trad-MCN assay records the genetic damage observed as frequency of micronuclei formed by entire chromosomes or fragments in the meiotic pollen mother cells and provides evidence of clastogenic or aneugenic damage. The Comet test does not need of cells in dividing phase and it is a useful tool to detect various forms of DNA damage such as single- and double- strand breaks and ossidative DNA base damage. As expected, toxicity results revealed that chronic effects are very higher than acute as demonstrated by the Acute/Chronic toxicity ratios that reached values about 1500 for some derivatives. The chronic data show that the compounds tested were bioactive at concentrations ranging from 0.017 to 7.36 mg/L mainly for the primary consumers Brachionus calyciflorus (rotifers) and Ceriodaphnia dubia (crustaceans) while they were no toxic or two orders of magnitude less active against algae (P. subcapitata). Variability in genotoxic responses was observed among compounds and tests, probably explainable by the different chemical characteristics of the pharmaceuticals investigated and the different endpoints of the bioassays utilized. Atenolol, furosemide and their respective derivatives showed the lowest genotoxic potential. The fibrates evidenced different responses in the four bioassays. The behavior of Gemfibrozil derivative was peculiar because it was the most active in all the bioassays performed and the only positive for S. typhimurium TA 100, the least sensitive strain to the environmental contaminants. In contrast, Gemfibrozil was the only fibrate that did not show any genotoxic effect. The use of a battery of tests appears to be a necessary methodological approach to suggest mechanisms at the base of genotoxic events.

Nanoparticles of organic carbon (NOC) are formed in combustion of hydrocarbon-rich fuels and have been detected in vehicle exhausts, suggesting their presence in urban atmospheres. Epidemiological studies showed that some causal relationships exist between particle concentration in the air and a wide range of health effects, but no toxicological studies are reported on the potential health risk of particles smaller than 4 nm. The present study investigated the mutagenicity and the reactivity of NOC collected in water samples from the exhausts of diesel and gasoline engines. Mutagenicity was tested following the Ames Test, with and without metabolic activation. Reactivity was investigated by using a new approach aimed to identify electrophilic agents present in the sample material, which if introduced into the organism, could interact with nucleophilic sites of biological macromolecules (DNA and proteins), forming adducts. Given the large number of nucleophilc sites within biological macromolecules, the complexity of NOC, and the inexact knowledge of its chemical structure, this approach was simplified by examining in vitro interactions between NOC particles and model peptides through LCIMS analyses of incubation mixtures The results indicate a high reactivity and, in several cases, the mutagenicity of NOCs, thus calling for suitable biomarkers assess NOC exposure associated with vehicle emissions.

Drugs are not environmentally different from other chemicals. High quantities of pharmaceuticals are discharged into sewage treatment plants when used for human cure and directly into surface waters or on soil when used for veterinary purposes. Drugs generally occur in low concentrations (ng-g/L) in various compartments of the aquatic environment Though antibacterial agents are known to have irreversible, no quantifiable effects on the gene pool of microrganisms (resistance), few data exist about the disturbance they cause to the wastewater treatment process, the microbial life in surface waters and their effects at low concentrations on other organisms. The ecotoxicity of the following six antibiotics on aquatic organisms was investigated: Erythromycin, Oxytetracyclin, Sulfamethoxazole, Ofloxacin, Lincomycin and Clarithromycin . Bioassays were performed on bacteria, algae, rotifers, microcrustaceans and fish to assess acute and chronic toxicity, while SOS chromotest and Ames test were used to detect the genotoxic potential of the investigated drugs. For risk assessment, the environmental impact was calculated by MEC/PNEC ratio using the available data from the literature regarding the occurrence in the aquatic environment of the pharmaceuticals investigated and the toxicity data obtained from the bioassays performed. The ecotoxicological results showed that acute toxicity was in the order of mg/L while, for the chronic data the antibiotics were bioactive at concentrations in the order of µg/L, mainly for the algae. The toxicity ratios of acute and chronic effect (A/C ratio) ranged for Brachionus calyciflorus from 3 (clarithromycin and sulphametoxazole) to 56 (ofloxacin) and for Ceriodaphnia dubia from 2 (clarithromycin and lincomycin) to 104 (oxytetracyclin), confirming that chronic assays are more appropriate than acute ones to detect the impact of pharmaceuticals. Ofloxacin was the only genotoxic compound and Sulfamethoxazole, Ofloxacin and Lincomycin were mutagenic. As for environmental risk, the macrolides were found to be the most harmful for the aquatic environment.

Many concerns raised recently regarded the environmental safety of alkylphenol polyethoxylate surfactants (APEOs).They are widely used in detergents, paints, herbicides and many other formulated products. It has been estimated that 60% of APEOs ends up in the aquatic environment; they are biodegraded and transformed into alkylphenols, such as nonylphenol and octylphenol that are hydrophobic and tend to accumulate in sediments. In this study we tested representatives of the most environmentally important groups of alkylphenolic compounds through a recombinant yeast bioassay using Saccaromices cerevisiae strain RMY326. The Yeast Estrogen Screen test (YES-test) is based on the DNA sequence of human estrogen receptor α (hER α) and the reporter gene lac-Z expressing the Escherichia coli enzyme β-galactosidase. Furthermore, we assessed the embryotoxicity of these compounds on the crustacean Daphnia magnathrough the well-known ability of alkylphenols to interfere with the metabolic elimination of testosterone. Daphnids (tert-octylphenol and 4-nonylphenol were the most potent (100 times less than 17β-estradiol used as control) with full dose-response curve. These data indicate that the use of recombinant yeast cells is an interesting complement to study the effects of xenobiotics on the response of vertebrate hormone receptors to the studies with test animals or vertebrate cell cultures. Furthermore, the most of APEOs investigated were also found to be embryotoxic. D. magna showed the first effects after three weeks of exposure even if the high concentrations (in the order of mcg/L), at which abnormalities occurred, indicate that environmental concentrations pose no imminent risk.

Pharmaceutical products for humans and animals, as well as their related metabolites end up in the aquatic environment after use. Recent investigations show that concentrations of pharmaceuticals are detectable in the order of ng/l-μg/l in municipal wastewater, groundwater and also drinking water. Little is known about the effects, and the hazard of long-term exposure to low concentrations of pharmaceuticals for non-target aquatic organisms. This study was designed to assess the ecotoxicity of furosemide, a potent diuretic agent, and its photoproduct in the aquatic environment. Bioassays were performed on bacteria, algae, rotifers and microcrustaceans to assess acute and chronic toxicity, while the SOS Chromotest and the Ames test were utilized to detect the genotoxic potential of the investigated compounds. A first approach to risk characterization was to calculate the environmental impact of furosemide by measured environmental concentration and predicted no effect concentration ratio (MEC/PNEC). To do so we used occurrence data reported in the literature and our toxicity results. The results showed that acute toxicity was in the order of mg/l for the crustaceans and absent for bacteria and rotifers. Chronic exposure to these compounds caused inhibition of growth population on the consumers, while the algae did not seem to be affected. A mutagenic potential was found for the photoproduct compared to the parental compound suggesting that byproducts ought to be considered in the environmental assessment of drugs. The risk calculated for furosemide suggested its harmlessness on the aquatic compartment. © 2005 Elsevier Ltd. All rights reserved.

The ecotoxicity of the following six antibiotics on aquatic organisms was investigated: Erythromycin, Oxytetracyclin, Sulfamethoxazole, Ofloxacin, Lincomycin and Clarithromycin. Bioassays were performed on bacteria, algae, rotifers, microcrustaceans and fish to assess acute and chronic toxicity, while SOS Chromotest and Ames test were used to detect the genotoxic potential of the investigated drugs. For risk assessment, the environmental impact was calculated by MEC/PNEC ratio using the available data from the literature regarding their occurrence in the aquatic environment and the toxicity data obtained from the bioassays performed. The ecotoxicological results showed that acute toxicity was in the order of mg/L while, for the chronic data the antibiotics were bioactive at concentrations in the order of μg/L, mainly for the algae. Drugs investigated were one or two order of magnitude less active against rotifers and crustaceans. Ofloxacin was the only genotoxic compound and Sulfamethoxazole, Ofloxacin and Lincomycin were mutagenic. As for environmental risk, the macrolides were found to be the most harmful for the aquatic environment. © 2004 Elsevier B.V. All rights reserved.

We examined the biological reactivity in vitro of nanoparticles of organic compounds (NOC) with diameters, d = 1-3 nm, a class of combustion-generated particulate relatively unstudied compared to larger more graphitic soot particles because of their small size even though they may contribute significantly to the organic fraction of PM sampled from vehicle exhausts and urban atmospheres. We tested NOC samples collected from 2004 model vehicle emissions and laboratory flames. NOC produced a dose dependent mutagenic response in Salmonella bacteria, suggesting that NOC may add significantly to the overall mutagenicity of vehicle emissions. Incubation with peptides caused agglomeration and precipitate of the otherwise stable NOC suspension, but the chemical and/or physical nature of the NOC-peptide interactions could not be resolved. A significant cytotoxic response was measured above a critical dose of NOC in mouse embryo fibroblasts NIH3T3 cells along with possible evidence of cellular uptake by optical and confocal microscopy. The toxicological assays showed that NOC collected from flames and vehicle exhausts effectively interacted in vitro with both prokaryotic and eukaryotic cells. Differences in mutagenic potencies observed for various Salmonella strains with and without metabolic activation indicate differences in the chemical composition of NOC collected from different vehicles and flames.

Lipid regulators have been detected in effluents from sewage treatment plants and surface waters from humans via excretion. This study was designed to assess the ecotoxicity of fibrates, lipid regulating agents. The following compounds were investigated: Bezafibrate, Fenofibrate and Gemfibrozil and their derivatives obtained by solar simulator irradiation. Bioassays were performed on bacteria, algae, rotifers and microcrustaceans to assess acute and chronic toxicity, while SOS Chromotest and Ames test were utilized to detect the genotoxic potential of the investigated compounds.The photoproducts were identified by their physical features and for the first risk evaluation, the environmental impact of parental compounds was calculated by Measured Environmental Concentrations (MEC) using the available data from the literature regarding drug occurrence in the aquatic environment and the Predicted No Effect Concentrations (PNEC) based on our toxicity data. The results showed that acute toxicity was in the order of dozens of mg/L for all the trophic levels utilized in bioassays (bacteria, rotifers, crustaceans). Chronic exposure to these compounds caused inhibition of growth population on rotifers and crustaceans while the algae seemed to be slightly affected by this class of pharmaceuticals. Genotoxic and mutagenic effects were especially found for the Gemfibrozil photoproduct suggesting that also byproducts have to be considered in the environmental risk of drugs. Keywords: Fibrates, Toxicity testing, Genotoxicity, Mutagenesis, Risk assessment

Background. N-methylcarbamate insecticides are widely used chemicals for crop protection. This study examines the hydrolytic and photolytic cleavage of benfuracarb, carbosulfan and carbofuran under natural conditions. Their toxicity and that of the corresponding main degradation products toward aquatic organisms were evaluated. Methods. Suspensions of benfuracarb, carbosulfan and carbofuran in water were exposed to sunlight, with one set of dark controls, for 6 days, and analyzed by 1H-NMR and HPLC. Acute toxicity tests were performed on Brachionus calyciflorus, Daphnia magna, and Thamnocefalus platyurus. Chronic tests were performed on Pseudokirchneriella subcapitata, and Ceriodaphnia dubia. Results and Discussion. Under sunlight irradiation, benfuracarb and carbosulfan gave off carbofuran and carbofuran-phenol, while only carbofuran was detected in the dark experiments. The latter was degraded to phenol by exposure to sunlight. Effects of pH, humic acid and KNO3 were evaluated by kinetics on dilute solutions in the dark and by UV irradiation, which evidenced the lability of the pesticide at pH 9. All three pesticides and phenol exhibited acute and higher chronic toxicity towards the aquatic organisms tested. Conclusion. Investigation on the hydrolysis and photolysis of benfuracarb and carbosulfan under natural conditions provides evidence concerning the selective decay to carbofuran and/or phenol. Carbofuran is found to be more persistent and toxic. Recommendations and Outlook. The decay of benfuracarb and carbosulfan to carbofuran and the relative stability of this latter pesticide account for many papers that report the detection of carbofuran in water, fruits and vegetables. © 2006 ecomed publishers (Verlagsgruppe Hüthig Jehle Rehm GmbH).