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Dissolved organic matter (DOM) is a complex mixture of carbon-based compounds present in natural aquatic systems, which significantly affects drinking water treatment processes. Biofiltration, utilising biologically active beds of porous medium, offers a low-energy and low-chemical solution for controlling bioavailable DOM. However, the impact of microbial community composition on DOM degradation in biofilters remains poorly understood. This study aimed to explore the abilities of microbial communities from the top, middle, and bottom (TOP, MID, and BOT) of a biofilter to process DOM. We showed varying growth rates on the DOM, with bottom community exhibiting the highest cell abundance at the end of the experiment (1.83 × 106 ± 9 × 103; 2.06 × 106 ± 1 × 104; 2.15 × 106 ± 7 × 103 cells/mL for the TOP, MID, and BOT, respectively). The three communities showed different preferences for utilising specific DOM fractions, with the bottom community targeting more complex ones. The microbial communities from the bottom of the biofilter had a higher relative abundance of the Curvibacter genus, suggesting it could play a crucial role in degrading complex DOM fractions. These findings highlight the influence of microbial community composition on DOM degradation in biofilters, providing valuable insights for optimising their performance. HIGHLIGHTS Communities were extracted from three different depths of a biofilter (TOP, MID, and BOT).; Communities differed in growth kinetics, with BOT showing the greatest growth.; The TOP and MID communities preferentially used the smaller fractions of DOM.; The BOT community used the more complex DOM fraction of humic substances.; Microbial communities from different depths of a biofilter exhibit distinct abilities to degrade DOM.;

Lo studio del turismo è una delle porte d’ingresso privilegiate per comprendere il territorio, non solo dal punto di vista economico. Il turismo svolge un ruolo essenziale nella dialettica sociale e spaziale che assegna significato ai luoghi: da una parte alimenta l’immaginario individuale e collettivo attraverso la produzione d’icone e di rappresentazioni; dall’altra modella i luoghi, che si fanno “turistici” attraverso trasformazioni visibili che spazializzano quelle stesse immagini. Dagli anni Settanta del secolo scorso, diversi osservatori hanno denunciato il fenomeno turistico come una nuova forma di alienazione, distruzione dell’ambiente o imperialismo. Sulla scia di questi ed altri richiami alla necessità di ripensare e governare un settore in continua crescita, è nato il cosiddetto turismo responsabile, una modalità di viaggio che soddisfa e rispetta i bisogni dei viaggiatori e delle regioni ospitanti e allo stesso tempo protegge e migliora le opportunità di determinati territori. Partendo da una riflessione sulle dimensioni, gli impatti e i cambiamenti in atto di uno dei fenomeni caratterizzanti la contemporaneità, questo articolo, così come la special issue che esso introduce, prende come caso di studio IT.A.CÀ_migranti e viaggiatori, il primo festival a livello europeo focalizzato esplicitamente sul tema del turismo responsabile. Il viaggio nelle diverse edizioni di IT.A.CÀ_migranti e viaggiatori permette di valutare presupposti, esiti e potenzialità future di esperienze e pratiche che negli ultimi anni, attraverso processi partecipativi di condivisione, co-progettazione, dialogo e sperimentazione, hanno cercato di coniugare la sostenibilità del turismo con il benessere dei cittadini, immaginando una valorizzazione del territorio che promuova la transizione verso una coabitazione sostenibile della Terra.

Being characterised by a variety of normative systems and systems of knowledge, contemporary societies are said to be pluralistic. Yet, some expressions of epistemic and legal pluralism are still ignored and rejected, due to the cognitive hegemony and legal centralism of Western modernity. The issue has been explored from different perspectives in the field of human and social sciences, having been investigated within the framework of Latin American neo-Marxist dependency theory, English post-colonial studies, world-systems theory, the theories of the Modernity/Coloniality group, and the Epistemologies of the South. Such approaches seem to be particularly effective when carrying out a comprehensive analysis of human rights, as global social justice cannot be achieved without global cognitive justice (de Sousa Santos 2007). Other languages can be used to talk about human dignity, with epistemic and legal pluralism making the various grammar rules of fundamental rights intelligible. Such an approach has been adopted by decolonial theory, which is experimenting with a new legal common sense. In this paper, reference will be made to the Epistemologies of the South, theorised by Portuguese sociologist of law Boaventura de Sousa Santos.

ABSTRACT Bdellovibrio bacteriovorus is a predatory, Gram-negative bacteria that feeds on many pathogenic bacteria and has been investigated as a possible solution for mitigating biofilms in different fields. The application depends on more fundamental ecological studies into the dynamics between Bdellovibrio and their prey. To do so requires an accurate, reliable, and, preferably rapid, way of enumerating the cells. Flow cytometry (FCM) is potentially a rapid, accurate, and inexpensive tool for this, but it has yet to be validated in the enumeration of Bdellovibrio. In this study, we developed a protocol to measure the number of Bdellovibrio in samples of various densities using FCM and compared the results with those of other methods: optical density (OD), PFU assay (PFU), and quantitative PCR (qPCR). We observed a strong correlation between values obtained using FCM and PFU (ρ = 0.923) and FCM and qPCR (ρ = 0.987). Compared to optical density there was a much weaker correlation (ρ = 0.784), which was to be expected given the well-documented uncertainty in converting optical density (OD) to cell numbers. The FCM protocol was further validated by demonstrating its ability to distinguish and count mixed populations of Bdellovibrio and the prey Pseudomonas. Thus, the accuracy of FCM as well as its speed and reproducibility make it a suitable alternative for measuring Bdellovibrio cell numbers, especially where many samples are required to capture the dynamics of predator-prey interactions. IMPORTANCE The rise of antibiotic resistance and the unwanted growth of bacteria is a universally growing problem. Predatory bacteria can be used as a biological alternative to antibiotics because they grow by feeding on other bacteria. To apply this effectively requires further study and a deeper understanding of the forces that drive a prey population to elimination. Initially, such studies require more reliable methods to count these cells. Flow cytometry (FCM) is potentially a rapid, accurate, and inexpensive tool for this, but it has yet to be validated for predatory bacteria. This study develops a protocol to count the predatory bacteria Bdellovibrio bacteriovorus and its Pseudomonas prey using FCM and compare the results with those of other methods, demonstrating its ability for studies into B. bacteriovorus predation dynamics. This could lead to the use of B. bacteriovorus for killing bacterial biofilms in fields, such as drinking water and agriculture.

Memory as a social concept may be declined both theoretically and empirically. In the first case, it raises a number of questions related to the interconnectionbetween individual and collective identities. In the second, it may be adopted as a an interpretive tool to be used in the empirical analysis of social processes. Both perspective (theoretical and empirical) will be adopted here in order to understand the social and political relevance of memory and its recover in present-day Argentina. The human rights movement operating in Argentina since 1976, is our focus, conceived here as an instances of the employment of social memories as a political tool. As an example of the social recovery of memory as a political instrument, the organization of Madres (Mothers) and Abuelas (Grandmothers) de Plaza de Mayo. Those organizations adopt creative methods to make memory and the past, having been socially reconstructed by the regime, as a form of political struggle and vindication.