Sequential Reductive/Oxidative Bioelectrochemical Process for Chlorinated Aliphatic Hydrocarbons Removal in Contaminated Groundwaters: Fluid Dynamic Characterization of the Scaled-Up Field Test

Chlorinated Aliphatic Hydrocarbons (CAHs) as Perchloroethylene (PCE) and Trichloroethylene (TCE) are worldwide contaminants due to their uncorrected disposal and storage in the past years. An effective remediation strategy for CAHs contaminated groundwaters is the stimulation of dechlorinating microorganisms which can carry out reductive and oxidative reactions that allowed for the complete mineralization of CAHs. More in detail, dehalorespiring microorganisms can reduce PCE and TCE throughout reductive dechlorination reaction (RD) a step happening reaction that remove a chlorine atom from the carbon skeleton of the molecule and replaces it with a hydrogen ion. Hence, aerobic dechlorinating microorganisms oxidize low chlorinated compounds such as cis-dichloroethylene (cDCE) and vinyl chloride (VC) into CO2 using enzymes, such as monooxygenases, to produce instable molecules with oxygen atom like epoxides. The combination of reductive and oxidative dechlorination could maximize the microbial activities allowing to work on the preferred substrates and can be easily tuned by the adoption of bioelectrochemical systems. In these electrochemical devices, an electrodic material interact with so-called electroactive microorganisms, acting like electron acceptor or donor of the microbial metabolism. In this study, a sequential reductive/oxidative bioelectrochemical process developed by the combination in series of two membrane-less microbial electrolysis cells (MECs) has been applied for the treatment of a CAHs contaminated groundwater coming from a polluted site in northern Italy. More in detail, the study presents the development and the validation of the sequential bioelectrochemical process under laboratory conditions and the and subsequent scale-up of the process for a field. The investigation of the laboratory scale performance was conducted by synthetic and real contaminated groundwater while the design and the characterization of the scaled-up process have been obtained with real contaminated in a field test. The scale-up allowed to increase the reactor volume 42 times (from 10 L to 420 L) dividing the reductive and the oxidative sections into 4 different columns with a volume of 105 L (Figure 1). The field test of the bioelectrochemical technology represents the most important scaled-up application in a bioelectrochemical system devoted to the remediation of CAHs contaminated groundwater, thus, it shows an effective solution for the stimulation of microbial activity without the utilization of any chemical in a real environment

The DLV System for Knowledge Representation and Reasoning

This paper presents the DLV system, which is widely considered the state-of-the-art implementation of disjunctive logic programming, and addresses several aspects. As for problem solving, we provide a formal definition of its kernel language, function-free disjunctive logic programs (also known as disjunctive datalog), extended by weak constraints, which are a powerful tool to express optimization problems. We then illustrate the usage of DLV as a tool for knowledge representation and reasoning, describing a new declarative programming methodology which allows one to encode complex problems (up to $\Delta^P_3$-complete problems) in a declarative fashion. On the foundational side, we provide a detailed analysis of the computational complexity of the language of DLV, and by deriving new complexity results we chart a complete picture of the complexity of this language and important fragments thereof. Furthermore, we illustrate the general architecture of the DLV system which has been influenced by these results. As for applications, we overview application front-ends which have been developed on top of DLV to solve specific knowledge representation tasks, and we briefly describe the main international projects investigating the potential of the system for industrial exploitation. Finally, we report about thorough experimentation and benchmarking, which has been carried out to assess the efficiency of the system. The experimental results confirm the solidity of DLV and highlight its potential for emerging application areas like knowledge management and information integration.Comment: 56 pages, 9 figures, 6 table

Clinical profile of trazodone users in a multisetting older population: data from the Italian GeroCovid Observational study

Background and objectives: Depression is highly prevalent in older adults, especially in those with dementia. Trazodone, an antidepressant, has shown to be effective in older patients with moderate anxiolytic and hypnotic activity; and a common off-label use is rising for managing behavioral and psychological symptoms of dementia (BPSD). The aim of the study is to comparatively assess the clinical profiles of older patients treated with trazodone or other antidepressants. Methods: This cross-sectional study involved adults aged ≥ 60 years at risk of or affected with COVID-19 enrolled in the GeroCovid Observational study from acute wards, geriatric and dementia-specific outpatient clinics, as well as long-term care facilities (LTCF). Participants were grouped according to the use of trazodone, other antidepressants, or no antidepressant use. Results: Of the 3396 study participants (mean age 80.6 ± 9.1 years; 57.1% females), 10.8% used trazodone and 8.5% others antidepressants. Individuals treated with trazodone were older, more functionally dependent, and had a higher prevalence of dementia and BPSD than those using other antidepressants or no antidepressant use. Logistic regression analyses found that the presence of BPSD was associated with trazodone use (odds ratio (OR) 28.4, 95% confidence interval (CI) 18-44.7 for the outcome trazodone vs no antidepressants use, among participants without depression; OR 2.17, 95% CI 1.05-4.49 for the outcome trazodone vs no antidepressants use, among participants with depression). A cluster analysis of trazodone use identified three clusters: cluster 1 included mainly women, living at home with assistance, multimorbidity, dementia, BPSD, and depression; cluster 2 included mainly institutionalized women, with disabilities, depression, and dementia; cluster 3 included mostly men, often living at home unassisted, with better mobility performance, fewer chronic diseases, dementia, BPSD, and depression. Discussion: The use of trazodone was highly prevalent in functionally dependent and comorbid older adults admitted to LTCF or living at home. Clinical conditions associated with its prescription included depression as well as BPSD