Potential Applications of Essential Oils for Environmental Sanitization and Antimicrobial Treatment of Intensive Livestock Infections

The extensive use of antibiotics has contributed to the current antibiotic resistance crisis. Livestock infections of Salmonella spp, Clostridium spp. and E. coli antimicrobial-resistant bacteria represent a public threat to human and animal health. To reduce the incidence of these zoonoses, essential oils (EOs) could be effective antibiotic alternatives. This study aims at identifying EOs safe for use, effective both in complementary therapy and in the environmental sanitization of intensive farming. Natural products were chemo-characterized by gas chromatography. Three S. Typhimurium, three C. perfringens and four E. coli strains isolated from poultry and swine farms were used to assess the antimicrobial properties of nine EOs and a modified GR-OLI (mGR-OLI). The toxicity of the most effective ones (Cinnamomum zeylanicum, Cz; Origanum vulgare, Ov) was also evaluated on porcine spermatozoa and Galleria mellonella larvae. Cz, Ov and mGR-OLI showed the strongest antimicrobial activity; their volatile components were also able to significantly inhibit the growth of tested strains. In vitro, Ov toxicity was slightly lower than Cz, while it showed no toxicity on G. mellonella larvae. In conclusion, the study confirms the importance of evaluating natural products to consolidate the idea of safe EO applications in reducing and preventing intensive livestock infections

Origanum vulgare essential oil vs. A commercial mixture of essential oils: In vitro effectiveness on salmonella spp. from poultry and swine intensive livestock

open11noSalmonella spp. represent a public health concern for humans and animals due to the increase of antibiotic resistances. In this scenario, the use of essential oils (EOs) could be a valid tool against Salmonella contamination of meat. This work compares the in vitro effectiveness of an Italian mixture of feed additives based on EOs (GR-OLI) with EO of Origanum vulgare L., recently admitted by European Food Safety Authority (EFSA) for animal use. Twenty-nine Salmonella serotypes isolated from poultry and pig farms were used to assess GR-OLI and O. vulgare EO antimicrobial propeties. O. vulgare EO was active on the disaggregation of mature biofilm, while GR-OLI was capable of inhibiting biofilm formation and disaggregating preformed biofilm. Furthermore, GR-OLI inhibited bacterial adhesion to Caco-2 cells in a dose-dependent manner. Both products showed inhibition of bacterial growth at all time points tested. Finally, the synergistic action of GR-OLI with commonly used antibiotics against resistant strains was investigated. In conclusion, the mixture could be used both to reduce the meat contamination of Salmonella spp. before slaughter, and in synergy with low doses of ciprofloxacin against resistant strains. Although EOs as feed additives are already used in animal husbandry, no scientific study has ever highlighted their real antimicrobial potential.openDi Vito M.; Cacaci M.; Barbanti L.; Martini C.; Sanguinetti M.; Benvenuti S.; Tosi G.; Fiorentini L.; Scozzoli M.; Bugli F.; Mattarelli P.Di Vito M.; Cacaci M.; Barbanti L.; Martini C.; Sanguinetti M.; Benvenuti S.; Tosi G.; Fiorentini L.; Scozzoli M.; Bugli F.; Mattarelli P

INVESTIGATION ON THE DYNAMIC BEHAVIOUR OF A WALL WITH A LAYER OF SOLID-LIQUID PHASE CHANGE MATERIAL

In Italy most buildings built before the seventies have external walls of low heat storage capability and of low thermal insulation level. The solution proposed in this work to improve the performance of these walls, is a retrofit by means of a layer of Phase Change Material (PCM). This technology is of particular interest because can contribute effectively to reduce the risk of overheating, to reduce the high cooling demand, with significant energy saving, and to improve the comfort, during the summer. The goal of this paper is the analysis of the energy behaviour of a conventional wall, where on the outer surface a thin layer of PCM is applied. In the analysis a control volume code is used. The external conditions are referred to a typical summer day. The performance of the storage systems are evaluated by comparison between a conventional wall and the same after the suggested retrofit. In the comparison the dynamic thermal characteristics, decrement factor and time shift, as suggested by EN ISO 13786, are used. The analytical solution proposed by the same standard is also used, when possible. For the conventional wall both the numerical and analytical results are used to obtain the dynamic thermal characteristics. For the wall with the PCM cover just the numerical can be used. The results show the effectiveness of the solution adopted, but make evident that the dynamic thermal characteristics of the wall with the layer of PCM are dependent on the boundary conditions. Finally the applicability of the EN ISO 13786 to this innovative kind of retrofit has been evaluated

Consultants as enablers of dynamic capabilities: a multiple case study

none3This study focuses on the process of change that firms undertake to overcome situations of organizational rigidity, thanks to the contribution of external actors, such as consultants. Previous literature about dynamic capabilities has become very rich in the last years; however, the models that explain how dynamic capabilities evolve are not particularly investigated. Literature about knowledge transfer claims that external actors can bring new elements that activate pathways of organizational change and the development of capabilities previously not present. This paper proposes relevant case studies in which external actors introduce new knowledge within organizations activating processes of change. Each case consists of an organizational consulting project. Consultants are interpreted as external actors who bring new knowledge that can be internalized by the client firm and can enable the development of new dynamic capabilities. Results show that consultants can play an active role in helping firms in overcoming conditions of organizational rigidity and in developing new dynamic capabilities.Sub-theme (SWG) 03 Professional Service Organizing and Leadership Convenors Celeste P.M. Wilderom, School of Management and Governance, University of Twente, The Netherlands; [email protected] Juani Swart, School of Management, University of Bath, UK; [email protected] Session I Friday, July 8, 09:00–11:00 location h-C22 Capabilities and Knowledge Renewal Chair: Juani Swart Philipp Meyer and Olivier Chatain How do firms match their resources to projects? Evidence from M&A legal advisors Tiina Tuominen Innovation and development activities as subsystems for change – Participation of employees in PSFs Giacomo Carli, Alessandro Grandi and Elisa Mattarelli Consultants as enablers of dynamic capabilities: A multiple case studynoneGiacomo Carli; Alessandro Grandi; Elisa MattarelliGiacomo Carli; Alessandro Grandi; Elisa Mattarell

Experimental and numerical investigation on the EGR system of a new automotive Diesel engine

In this paper an integrated experimental and numerical approach is applied to optimize a new 2.5l, four valve, turbocharged DI Diesel engine, developed by VM Motori. The study is focused on the EGR system

Analisi termofluidodinamica di sistemi di scarico per motore automobilistico aspirato ad accensione comandata

Le prestazioni di un motore alternativo a combustione interna sono principalmente influenzate dall'efficienza dei processi di ricambio della carica. Lo studio di tali processi, possibile con l'ausilio di codici termofluidodinamici 1-D, costituisce pertanto una base per l'ottimizzazione dei sistemi di aspirazione e scarico.In questo lavoro sono anzitutto discussi gli aspetti fluidodinamici caratteristici ed i criteri di progetto del sistema di scarico per un motore aspirato a quattro tempi, policilindrico.Lo studio e' stato quindi indirizzato ad un motore automobilistico di produzione Maserati, 8 cilindri a V, di cui sono definite tutte le caratteristiche tranne la geometria del sistema di scarico. Per le due configurazioni dello scarico piu' comunemente impiegate in una bancata a quattro cilindri (4-1 e 4-2-1), e tenendo conto dei vincoli progettuali, e' stata effettuata un'analisi d'influenza dei parametri geometrici ritenuti piu' significativi.La migliore soluzione 4-2-1 fornisce, rispetto alla corrispondente 4-1, prestazioni piu' elevate ai medi regimi di rotazione

Experimental and numerical investigation on the EGR system of a new automotive diesel engine

In this paper an integrated experimental and numerical approach is applied to optimize a new 2.5l, four valve, turbocharged DI Diesel engine, developed by VM Motori. The study is focused on the EGR system. For this engine, the traditional dynamometer bench tests provided 3-D maps for brake specific fuel consumption and emissions as a function of engine speed and brake mean effective pressure. Particularly, a set of operating conditions has been considered which, according to the present European legislation, are fundamental for emissions. For these conditions, the influence of the amount of EGR has been experimentally evaluated. A computational model for the engine cycle simulation at full load has been built by using the WAVE code. The model has been set up against experiments, since an excellent agreement has been reached for all the relevant thermo-fluid-dynamic parameters. The simulation model has been used to gain a better insight on the EGR system operations. Furthermore, the influence of the most important geometric parameters (EGR valve seat diameter, intake manifold throttle diameter) on the amount of recycled gas for a few critical operating conditions has been investigated. Copyright © 2000 Society of Automotive Engineers, Inc

SI Engines 1D Modeling: Prediction of Brake Performance Parameters and Emissions.

1D simulation codes, including thermodynamic, fluid dynamic and chemical models, are fundamental tools for engine design and optimization. The GASDYN code, developed by the authors at the Politecnico of Milano, has been used to analyze the operations of a Maserati S.I., naturally aspirated, V8 engine. An experimental campaign was previously carried out on this engine, including the measurement of brake performance parameters and exhaust emissions and in-cylinder pressure cycles, for several operating conditions at both full and partial load. This large amount of data allowed the authors to set up and validate at full load a numerical model of the engine. A multi-zone fractal model has been employed to predict combustion heat release, as well as NO, CO and HC emissions. After the experimental validation, the engine model has been used to calculate engine performances and emissions at partial load. A very satisfactory agreement was found