58 research outputs found
Testing for optimal monetary policy via moment inequalities
The specification of an optimizing model of the monetary transmission mechanism requires selecting a policy regime, commonly commitment or discretion. In this paper we propose a new procedure for testing optimal monetary policy, relying on moment inequalities that nest
commitment and discretion as two special cases. The approach is based on the derivation of bounds for in
ation that are consistent with optimal policy under either policy regime. We derive testable implications that allow for specification tests and discrimination between the
two alternative regimes. The proposed procedure is implemented to examine the conduct of monetary policy in the United States economy
Legionella spp. Monitoring in the Water Supply Systems of Accommodation Facilities in Sardinia, Italy: A Two-Year Retrospective Analysis
Travel-associated Legionnaires’ disease is a significant public health concern worldwide. A high number of cases are reported every year among travellers who stay at guest houses, hotels, and spas. Indeed, hot water systems, showers, and air-conditioning systems can be contaminated by Legionella, which grows at 25–42 °C. Studies have shown that in Sardinia, especially during the summer months, the water circulation in the hotels’ pipes is exposed to extremely high temperatures. As a result, this study was conducted to assess the colonization of hotel water systems by Legionella in Sardinia, concerning a recent EU directive 2020/2184 for drinking water with a limit of 1000 CFU /L. Methods. A total of 112 accommodation facilities were analyzed, of which 61.3% were found to be colonized with Legionella, and out of a total of 807 samples, 32.5% were positive for Legionella presence. The results showed a higher number of positive samples in the summer season. This was also associated with the higher concentration presence of >1000 CFU/L in the samples. Consequently, this study confirms that local hotel operators should improve their water safety and prevention plans, especially in spring and summer
Microbiological characterization of a rearing system for the common sea urchin Paracentrotus lividus: a support to technical production regulations redaction and system monitoring
Objective: The overexploitation of the sea urchin Paracentrotus lividus stock, as a consequence of the growing market demand for roe, has boosted the research for echinoderm rearing. The chemical, physical, and microbiological characteristics of land-based facilities are crucial for sea urchins' health and human consumption of their products. In Italy, health-hygienic regulations for P. lividus rearing are still to be perfected by the authorities. In this context, we characterized the microbiological quality of a pilot land-based facility for sea urchin production at the University of Cagliari (Italy) to support the development of technical production regulations.Materials and Methods The accredited Hygiene Laboratory of Cagliari University collected and analyzed the samples in June 2023. Mesophilic bacteria, yeasts, and molds were searched for in air and on surfaces. Total coliforms and Escherichia coli, Enterococci, Pseudomonadaceae, Staphylococcus aureus, sulfite-reducing Clostridia, and Vibrio spp. were identified in water samples. We searched forVibrio spp. and Pseudomonas spp. in the gonads and coelomic fluid of sea urchins.Results Although air, surfaces, and water quality were satisfactory overall, some critical points should be monitored more strictly. Enterococci concentration was 250 CFU/100 mL in the water reserve, suggesting animal contamination (other than humans). Pseudomonas aeruginosa was the most resistant to filtration processes, with a residual concentration of 6 CFU/250 mL after the second filtration. No colonies of Vibrio spp. or Pseudomonas spp. were isolated in sea urchins' gonads or coelomic fluid.Conclusions Starting from the results, we provided targeted advice for developing technical production regulations, system monitoring, and facility routine maintenance in accordance with the 'best practice' approach. This analysis could be considered a first step toward the elaboration of common regulations about the minimal standards for the breeding environment of P. lividus by national and regional authorities
Evaluation of growth potential and growth dynamics of Listeria monocytogenes on ready-to-eat fresh fruit
The consumption of fresh or RTE fruits is increasing every year and Listeria monocytogenes has been identified on raw or minimally processed fruits. A food product can become contaminated with L. monocytogenes anywhere along the pathway of food production during planting, harvesting, packaging, distribution and serving. The aim of this work was to assess the microbiological risks associated with consumption of ready-to-eat fruit such as melon, pineapple, coconut and fruit salad. The presence of Escherichia coli, Salmonella spp. and L. monocytogenes was also evaluated. Microbiological challenge tests were carried out for the evaluation of the L. monocytogenes growth potential in RTE fruit stored at 4 and 8°C. E. coli counts resulted under the detection limit of 10 CFU g-1, Salmonella and L. monocytogenes were not detected (absence in 25g). The growth potential values in coconut and melon (δ>0.5) showed the growth capacity of Listeria at the temperatures considered. A low initial load, also derived from good hygiene practices, and correct storage temperatures are essential to reduce bacterial growth in RTE fruit. The challenge test showed how each type of RTE fruit has a different commercial life based on its specific growth potential and that food should be stored at temperatures not higher than 4°C for a short period
Microbiological environmental monitoring in high-risk departments during building activities in a hospital site
Background. This study examines the microbial and fungal contamination associated with the presence of renovation works in a hospital site in Sardinia (Italy). Methods. Microbiological environmental monitoring was carried out before, during and at the conclusion of the works in the Ophthalmology Department in view of a risk assessment procedure. Results. Although the median values of microbial and fungal counts were found raised during the works, protective measures set out by the internal procedures limited the contamination level. Conclusions. This study emphasizes the benefits of environmental surveillance for airborne contamination to help prevent outbreaks of nosocomial mycosis associated with construction work
Antimicrobial Activity of Grapefruit Seed Extract on Edible Mushrooms Contaminations: Efficacy in Preventing Pseudomonas spp. in Pleurotus eryngii
Pleurotus eryngii is an edible mushroom that suffers significant losses due to fungal contamination and bacteriosis. The Pseudomonadaceae family represents one of the most frequent etiologic agents. Grapefruit seed extract (GSE) is a plant extract that contains different bioactive components, such as naringin, and exhibits a strong antibacterial and antioxidant activity. Over the last decade, GSE use as an alternative to chemical treatments in the food sector has been tested. However, to our knowledge, its application on mushroom crops has never been investigated. This study focuses on evaluating GSE efficacy in preventing P. eryngii yellowing. GSE antibiotic activity, inhibitory and bactericidal concentrations, and antibiofilm activity against several microorganisms were tested with the Kirby–Bauer disk diffusion assay, the broth microdilution susceptibility test, and the Crystal violet assay, respectively. In vitro, the extract exhibited antimicrobial and antibiofilm activity against Staphylococcus aureus 6538 and MRSA (wild type), Escherichia coli ATCC 8739, and Pseudomonas spp. (Pseudomonas aeruginosa 9027, P. fluorescens (wild type)). GSE application in vivo, in pre- and post-sprouting stages, effectively prevented bacterial infections and subsequent degradation in the mushroom crops: none of the P. eryngii treated manifested bacteriosis. Our findings support the use of GSE as an eco-friendly and sustainable alternative to chemical treatments for protecting P. eryngii crops from bacterial contamination, consequently ensuring food safety and preventing financial losses due to spoilage. Furthermore, GSE’s potential health benefits due to its content in naringin and other bioactive components present new possibilities for its use as a nutraceutical in food fortification and supplementation
Il quartiere edilizio ritrovato sotto la chiesa di Sant’Eulalia a Cagliari
The paper concerns the buildings under the church of St. Eulalia at Cagliari (Sardinia – Italy). Some ruins relating to the
Late Antiquity and Early Middle Age put to light during the archaeological excavations from 1990 and 2008are very
interesting to study the urbanism of the ancient town as well as the wall texture. The stone seems to be the most used
through the different phases. In the last period they used also the opus africanum, coming from Africasince Punic age,
but re-used in Vandal and Byzantine times.
In wall textures as in structural/decorative parts (architraves, worked cornices, etc.) have been used mainly local
sedimentary lithologies of the Cagliari Miocene series: i.e., "Pietracantone", "Tramezzario", "Pietra forte". The first two
are the most used, but they have frequent decay problems due to their minero-petrographic characteristics and of high
porosity.
The biodeterioration of cultural heritage caused by different biological agents is very important and should always be
considered in relation to environmental conditions such as temperature and humidity. The results of the research in the
archaeological area of St. Eulalia showed that microbial contamination was represented by a multiplicity of bacteria and
fungi, sometimes visible macroscopically
Chemical-physical agents and biodeteriogens in the alteration of limestones used in coastal historical fortifications
The alteration of rocks is usually due to the chemical-physical processes that are initially established on the outer surface of the stone and gradually proceed towards the inner matrix. The chemical alteration generated by the interaction with atmospheric agents (weathering) involves the transformation of the mineral phases constituting the rock that are less stable in the current climatic conditions. That often leads to the formation of new secondary phases more stable with respect to the alteration. However, among these phases are often present some very soluble and hygroscopic phases (i.e., soluble salts, clay minerals) that cause inner degradation of the rock, due to their physical-mechanical actions (inner crystallization pressure, hydration dilation). In the case of carbonate rocks (limestone, sandstone with carbonate cement, etc.), the dissolution is the more frequent process, especially when the monuments were located within the cities, due to the acid meteoric precipitations (with H2CO3, H2SO4) that lead to the sulfation of carbonate matrix with formation of gypsum, very harmful to the stone. When the rock (e.g., clay-arenaceous limestones) naturally contains hygroscopic phases inside the matrix (i.e., marine salts, phyllosilicates) and they are also porous (> 20%), the physical degradation is accelerated, with decohesion of the mineralogical matrix (between the crystalline granules) and consequent disintegration of the stone. In the rock-atmosphere interaction often occurs the presence of biodeteriogens (plants, fungi, lichens, micro- organisms, etc.), which negatively participate and in various ways in the processes of rock alteration.
The research aims to define the chemical-physical alteration factors on the limestones exposed to different bioclimatic and biogeographic contexts (Mediterranean and Atlantic), taking two study-case monuments located in the Italian and in the Portuguese coasts. In the study presented in this paper the preliminary results of the case-study of Cagliari fortifications have been discussed. In the study the different vascular plants present on stone surface and crevices and their different role in the degradation of limestone rocks have been also studied
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