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Population dynamics of Procambarus clarkii as a function of the body submersion/floating stage
No full textProcambarus clarkii (Girard, 1852) is a freshwater crayfish, native of Southern USA, which spread in Europe after its introduction for aquaculture. Little information is available on the decomposition of bodies in freshwater systems, yet the study of body transformations in this environment is important for the estimation of the minPMI and the alterations of the body that may affect the estimation of the cause of death. In previous experiments, the importance of P. clarkii in the consumption of dead bodies in freshwater systems was assessed.
A new series of experiments was set out in order to analyze the population dynamics of P. clarkii in relation to the position of the body in the water column, and, therefore, with the decomposition stage of the carcass. The experiments were performed in Nonantola (MO), Northern Italy (both during summer, one in July and the other in August). In each experiment, five pig carcasses (Sus scrofa, L) enclosed in lobster pots were placed inside an artificial freshwater dew pond (67m x 15m, with a maximum depth of 1,5m). The number of P. clarkii detected on each carcass was recorded following an established sampling protocol, together with water level and meteorological data.
Results of both experiments show two main crayfish population peaks on the carcasses: the first peak occurs immediately after the deposition of the body inside the pond and the second one occurs 7-10 days after the placement, at the end of the floating stage. This peculiarity is probably connected with a difficulty for the crayfish to reach the carcasses during the floating stage, because of their poor swimming ability. Both peaks occurred in the submersion stage, with the carcass lying on the pond bottom, where it was easily reachable by crayfish.
This study is important in the forensic field related to freshwater systems, because the feeding activity of P. clarkii is crucial in the dismemberment of the body in water. These experiments showed differences in the colonization of the body in relation to its position in the water column. This may be useful for the estimation of the minPMI interval on bodies found in freshwater ponds
Entrepreneurial Tradition: How Stakeholders Are Enrolled in Italian Industrial Districts
No full textPostmortem injuries caused by the freshwater crayfish Procambarus clarkii
No full textThe feeding activity of animals can affect the decomposition of human cadavers because of tissue laceration and consumption. Nonetheless postmortem animals' activity may cause considerable damage to the body, producing perimortem wounds' modification that could lead to an incorrect assessment of the PMI or a wrong cause of death. Moreover, evaluation of aquatic arthropods activity can be useful in estimating the PMSI (Post Mortem Submersion Interval).
Procambarus clarkii (Girard, 1852) is a freshwater crayfish native of south-eastern USA, present in Europe with invasive populations, that are found also in Northern Italy. Previous experiments assessed the influence of the crayfish in the decomposition of animal carcasses in a freshwater system. The aim of this study was to investigate the role of P. clarkii as a carrion-feeder, studying the type and outline of the wounds caused by the crayfish's feeding activity on the carcasses.
Two experiments were performed in Nonantola (MO), Northern Italy (both during summer, one in July and one in August). Five pig carcasses (Sus scrofa) enclosed in lobster pots were placed inside an artificial freshwater dew pond. For each carcass the number of feeding P. clarkii, together with the type and size of lesion was carefully recorded following a fixed sampling protocol, together with water level and meteorological data.
Results show that in both the experiments, the Crustaceans attacked the carcasses a few hours after their positioning, starting to damage the external epidermal layer with lacerations up to 4cm, generally ascribable to round shape wounds. In the following days, the crayfishes continued their activity, increasing the percentage of damaged skin until the full laceration of the dermal layer. From that moment, the feeding activity continued mostly in the internal part of the carcass, with the attack of the internal organs, until the flesh was completely eaten and only bones remained.
The study of post mortem injuries could be very important in real cases of dead bodies recovered in freshwater systems, because the typical shape of the wounds caused by the Crustaceans could be confused for sharp force injuries and lead to a wrong report on the causes of death
Ruolo di Procambarus clarkii (Girard, 1852) nella decomposizione di corpi in ambiente d’acqua dolce
No full textL’entomologia forense è una disciplina delle scienze forensi in cui informazioni riguardanti insetti ed altri artropodi sono utilizzate per trarre conclusioni su casi giuridici, in particolare in ambito medico-legale. Numerosi studi sulla decomposizione di cadaveri sono stati condotti in ambiente terrestre, mentre scarse informazioni sono attualmente disponibili per quanto riguarda gli ambienti acquatici. A questo scopo è stata effettuata una serie di studi presso l’oasi della Partecipanza Agraria di Nonantola (MO), che ha rilevato l’importanza del ruolo del crostaceo Procambarus clarkii nella decomposizione di carcasse in ambienti di acqua dolce della Pianura Padana. Originario del sud degli Stati Uniti, a seguito alla sua introduzione in Europa per motivi commerciali, P. clarkii ha rappresentato un’importante discriminante negli ecosistemi acquatici, alterando significativamente l’ecologia e le catene trofiche. Con lo scopo di caratterizzare il ruolo di questo crostaceo nella decomposizione di cadaveri animali, anche in relazione alle stagioni, carcasse di Sus scrofa sono state posizionate all’interno di nasse metalliche in diversi punti di uno specchio d’acqua dolce artificiale (67mx15m), ripetendo l’esperimento in 4 diversi periodi dell’anno (1°ciclo Luglio; 2°ciclo Agosto-Settembre; 3°ciclo Novembre-Febbraio; 4°ciclo Marzo-Aprile). Da ogni esperimento sono stati raccolti i dati sulle popolazioni di crostacei presenti su ogni carcassa tramite campionamenti prestabiliti, i parametri meteorologici dell’area di studio e dello specchio d’acqua in questione, ed una documentazione fotografica delle ferite post-mortali inferte dai crostacei sulle carcasse. I risultati hanno evidenziato che la popolazione di P. clarkii che colonizzava le carcasse mostrava un andamento su base stagionale, verosimilmente correlato al ciclo vitale del crostaceo ed in particolare alle necessità trofiche a scopo riproduttivo. Inoltre, si è evidenziata una correlazione tra stadio decompositivo della carcassa e popolazione dei crostacei in nutrimento, con picchi significativi durante gli stadi decompositivi “submerged fresh” (immediatamente dopo la deposizione in acqua) e fine del “floating decay” (fase in cui la carcassa torna ad adagiarsi sul fondale, a seguito del periodo in galleggiamento). Tale andamento può essere messo in relazione con le scarse abilità natatorie del gambero, tali da rendere più facile la colonizzazione durante la fase sommersa, e più difficile durante la fase di galleggiamento. Un dato di particolare interesse è rappresentato dalle ferite post-mortali che l’attività nutritiva di P.clarkii infligge alla carcassa. Queste, di forma tendenzialmente circolare, risultano facilmente confondibili con ferite causate da arma da taglio o da sparo, conferendo quindi a questo studio un’importante rilevanza dal punto di vista strettamente forense. In conclusione, P.clarkii, e la sua influenza nella decomposizione di carcasse in ambiente di acqua dolce assumono fondamentale importanza dal punto di vista medico-legale, considerate le importanti modificazioni post-mortali che l’attività di questo crostaceo infligge ai corpi immersi
Body colonization and degradation in a freshwater system: the role of the crayfish Procambarus clarkii
No full textThe study of decay in freshwater systems is important for the estimation of the mPMI, the PMSI and the manner of death. In previous experiments, the importance of Procambarus clarkii in the consumption of dead bodies in freshwater was assessed. The present study aimed at characterizing the role of P. clarkii in the decomposition of carcasses by studying the population dynamics in relation to the decomposition stage and the wounds caused by the crayfish's feeding activity.
The study was conducted in Nonantola, Northern Italy, and consisted in two experiments, one in July, and one in August-September. Five pig carcasses enclosed in lobster pots were placed inside a freshwater dew pond. The number of P.clarkii detected on each carcass was recorded following a fixed sampling protocol, together with the type and outline of the wounds caused by the crayfish's feeding activity, and meteorological data.
Results show that the Crustaceans attacked the carcasses a few hours after their positioning, starting to damage the external epidermal layer with lacerations up to 4cm, generally ascribable to round shape wounds. The initial day corresponded with the first peak in P. clarkii population with up to 100 specimens detected in each lobster pot. In the following days, the crayfishes continued their activity, increasing the percentage of damaged skin, until the full laceration of the dermal layer. The second peak in crayfish's population occurred at end of the floating decay stage, with the carcass lying on the pond's bottom. From that moment, the feeding activity continued in the internal part of the carcass, until the flesh was completely consumed.
This study shows that the feeding activity of P.clarkii is crucial in the dismemberment of bodies in freshwater, and the importance in the forensic field is on two main points. First, by detecting differences in the colonization in relation to the position in the water column, these results are useful for the estimation of the mPMI interval; second, it emerged that the typical shape of the wounds made by the Crustaceans could be confused for sharp force injuries which could lead to a wrong report on the causes of death
As ASM-based Model for Grid Job Management
No full textJob Execution Management Services in Grid systems are generally implemented using specific Grid
middleware, and they are considered very critical for the success of the entire system. In order to better
manage complexity and criticality, literature suggests the use of robust formal models to describe and
analyze these services. This paper abstracts strategic services in Grid Systems, proposes an Abstract
State Machine-based model to design them, and implements them by the coreASM tool. The obtained
results lead to consider the usage of Abstract State Machine models as a concrete control appliance for
Grid system
Family firms, family boundary organizations and the family-related organizational ecosystem
Full text linkWhile entrepreneurial families often expand their activity over multiple businesses and patrimonial assets, this complexity is rarely addressed in mainstream family business research, where the predominant focus is on the family business or, at best, on the family controlling the operational business. We advance a more holistic understanding of entrepreneurial families that contemplates the variety of assets they create or acquire over time that jointly generate financial and socioemotional wealth for the family, and call for attention to the variety of organizations that entrepreneurial families establish to preserve, manage, and/or administer such assets. We theorize that each of these organizations can be devised as a family boundary organization (FBO), which operates at the interface of the entrepreneurial family and other systems, and such FBOs form a family-related organizational ecosystem. We propose a new framework that extends the scope of research beyond the family business and focuses more directly on entrepreneurial families and on the boundaries between the entrepreneurial family, its multiple assets, and the FBOs in the family-related organizational ecosystem. This framework paves the ground to extend the three-circle model, broadening the scope of family business research to consider a wider range of organizations besides the family firm, such as family foundations, family business foundations, family offices, family holdings, family academies, and family museums. Drawing on the organizational boundaries literature, we integrate organizational boundaries in the theory of the family firm and propose a research agenda to examine the entrepreneurial family and its assets in a broader way
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