A stochastic interspecific competition model to predict the behaviour of Listeria monocytogenes in the fermentation process of a traditional Sicilian salami

The present paper discusses the use of modified Lotka-Volterra equations in order to stochastically simulate the behaviour of Listeria monocytogenes and Lactic Acid Bacteria (LAB) during the fermentation period (168 h) of a typical Sicilian salami. For this purpose, the differential equation system is set considering T, pH and aw as stochastic variables. Each of them is governed by dynamics that involve a deterministic linear decrease as a function of the time t and an "additive noise" term which instantaneously mimics the fluctuations of T, pH and aw. The choice of a suitable parameter accounting for the interaction of LAB on L. monocytogenes as well as the introduction of appropriate noise levels allows to match the observed data, both for the mean growth curves and for the probability distribution of L. monocytogenes concentration at 168 h.Comment: 19 pages, 2 figures, 2 tables. To be published in Eur. Food Res. Techno

Unexpected reversal of the enantioselectivity using chiral quinolylmethyl- and acridininyloxazokines as ligands for asymmetric palladium-catalyzed allylic alkylation

New chiral quinolylmethyloxazolines and acridininyloxazolines were prepared and assessed in the enantioselective palladium-catalyzed allylic substitution of 1,3-diphenylprop-2-enyl acetate with dimethyl malonate. The introduction of a benzo-fused substituent on the pyridine ring not containing the chiral backbone resulted in the switch of the expected chiral sense of enantioselection of the reaction. Enantiomeric excesses up to 78% were obtained

Consumers of flowers and ornamental plants: an eploratory survey in the Italian «Mezzogiorno» regions

This paper aims to provide further knowledge of purchase and consumption behaviours with regard to flowers and ornamental plants in the regions of Italian «Mezzogiorno», as an acknowledgement of the centrality of final demand in the chain process. The knowledge of consumption process is fundamental either to the firm – in order to improve commercial strategies – or to competition authorities – with the purpose of implementing more effective policies. From the analysis carried out it emerges that flowers and ornamental plants consumption in the «Mezzogiorno» regions is characterised by a high penetration index and – just with regard to some commodities – by a low purchase frequency. Purchase – mainly in specialized flower shops – is made both to satisfy personal requirements and as a present for special occasions. With the only exception of flowers, consumption is not tied to specific occasions. In the «Mezzogiorno» regions this sector is actually showing a good growth potential in both productive and consumption terms. It is of primary importance to carry out actions consisting in an improvement of information and awareness among consumers about flowers and ornamentals, and a more diversified supply of products in order to get into the modern distribution chains.Cette étude vise à offrir une connaissance plus approfondie des comportements d’achat et de consommation de fleurs et de plantes ornementales dans les régions du « Mezzogiorno » d’Italie, en reconnaissant l’importance de la demande tout au long de la filière. La compréhension du processus de consommation a une très grande importance soit pour les entreprises, afin d’améliorer leurs stratégies commerciales, soit pour les autorité qui gèrent la concurrence, pour la mise en place de politiques plus efficaces. L’analyse empirique montre que, dans les régions du « Mezzogiorno » d’Italie, la consommation de fleurs et de plantes a un taux élevé de pénétration mais, pour certains produits, une faible fréquence d’achat. En particulier, l’achat, réalisé surtout dans les magasins spécialisés dans la vente de fleurs et de plantes, vise à satisfaire, d’une coté, les besoins des consommateurs, et, de l’autre, les besoins d’achat des cadeaux dans des circonstances spécifiques. Dans les régions étudiées, le secteur des fleurs et des plantes montre des potentialités de développement de plus en plus croissant sur le plan productif mais aussi en termes de consommation. Dans ce scénario, il serait souhaitable de mettre en place des actions et des outils pour à améliorer l’information et la sensibilisation des consommateurs sur les caractéristiques des produits concernés, mais aussi, de diversifier l’offre, de façon à pouvoir accéder aux nouvelles chaînes de la distribution

Assessment of membrane plants for biogas upgrading to biomethane at zero methane emission

In the future energy infrastructure there is a considerable potential for biogas and, in particular, for biomethane as a natural gas substitute. Among the alternatives of upgrading biogas to biomethane, this work focuses on membrane permeation. Taking cellulose acetate as membrane material and spiral-wound as membrane configuration, five layouts are assessed. All layouts have the same biogas plant rated at 500 m3/h (STP), yet they may adopt: (i) one- or two-stage permeation, (ii) permeate or residue recycle, and (iii) a water heater or a prime mover (internal combustion engine or a micro gas turbine) to exploit residues as fuel gas. Since residues are consumed, all layouts have zero emission of methane into the atmosphere. The membrane material is modeled considering the phenomenon of plasticization; the membrane modules are described by a crossflow permeation patterns without pressure drops. The results indicates that specific membrane areas range from 1.1 to 2.4 m2h/m3 (STP), specific energy from 0.33 to 0.47 kWh/m3 (STP), and exergy efficiencies from 57.6% to 88.9%. The splitting of permeation over two stages and the adoption of water heater instead of prime movers is a convenient option. The preferred layout employs a single compressor, a two-stage membrane permeation at 26 bar, a water heater fueled by the first-stage permeate, and a second-stage permeate recycle. Assuming a biomethane incentive of 80 €/MWhLHV and a project life of 15 years, the total investment of this plant is 2.9 M€, the payback time 5 years and the net present value 3.5 M€

Enhanced osteogenic differentiation in zoledronate-treated osteoporotic patients

Bisphosphonates are well known inhibitors of osteoclast activity and thus may be employed to influence osteoblast activity. The present study was designed to evaluate the in vivo effects of zoledronic acid (ZA) on the proliferation and osteoblastic commitment of mesenchymal stem cells (MSC) in osteoporotic patients. We studied 22 postmenopausal osteoporotic patients. Densitometric, biochemical, cellular and molecular data were collected before as well as after 6 and 12 months of ZA treatment. Peripheral blood MSC-like cells were quantified by colony-forming unit fibroblastic assay; their osteogenic differentiation potential was evaluated after 3 and 7 days of induction, respectively. Circulating MSCs showed significantly increased expression levels of osteoblastic marker genes such as Runt-related transcription factor 2 (RUNX2), and Osteonectin (SPARC) during the 12 months of monitoring time. Lumbar bone mineral density (BMD) variation and SPARC gene expression correlated positively. Bone turnover marker levels were significantly lowered after ZA treatment; the effect was more pronounced for C terminal telopeptide (CTX) than for Procollagen Type 1 N-Terminal Propeptide (P1NP) and bone alkaline phosphatase (bALP). Our findings suggest a discrete anabolic activity supported by osteogenic commitment of MSCs, consequent to ZA treatment. We confirm its anabolic effects in vivo on osteogenic precursors

Reply to "Comment on Iavicoli et al. Ethics and Occupational Health in the Contemporary World of Work. Int. J-Environ. Res. Public Health 2018, 15, 1713"

Non peer reviewe

A global survey on occupational health services in selected international commission on occupational health (ICOH) member countries

Background: The United Nations General Assembly (UNGA), the International Labour Organization (ILO), the World Health Organization (WHO), the International Commission on Occupational Health (ICOH), and the European Union (EU) have encouraged countries to organize occupational health services (OHS) for all working people irrespective of the sector of economy, size of enterprise or mode of employment of the worker. The objective of this study was to survey the status of OHS in a sample of countries from all continents. Methods: A questionnaire focusing on the main aspects of OHS was developed on the basis of ILO Convention No. 161 and several other questionnaire surveys used in various target groups of OHS. The questionnaire was sent to 58 key informants: ICOH National Secretaries. Results: A total of 49 National Secretaries responded (response rate 84.5%), from countries that employ 70% of the total world labour force. The majority of the respondent countries, 67%, had drawn up an OHS policy and implement it with the help of national occupational safety and health (OSH) authorities, institutes of occupational health or respective bodies, universities, and professional associations. Multidisciplinary expert OHS resources were available in the majority (82%) of countries, but varied widely in quantitative terms. The average OHS coverage of workers was 24.8%, with wide variation between countries. In over two thirds (69%) of the countries, the content of services was mixed, consisting of preventive and curative services, and in 29% preventive only. OHS financing was organized according to a mixed model among 63% and by employers only among 33% of the respondents. Conclusions: The majority of countries have drawn up policies, strategies and programmes for OHS. The infrastructures and institutional and human resources for the implementation of strategies, however, remain insufficient in the majority of countries (implementation gap). Qualitatively, the content and multidisciplinary nature of OHS corresponds to international guidance, but the coverage, comprehensiveness and content of services remain largely incomplete due to a lack of infrastructure and shortage of multiprofessional human resources (capacity gap). The estimated coverage of services in the study group was low; only a quarter of the total employed population (coverage gap).Peer reviewe

Application of an interspecific competition model to predict the growth of Aeromonas hydrophila on fish surfaces during the refrigerated storage

The growth of Aeromonas hydrophila and aerobic natural flora (APC) on gilthead seabream surfaces was evaluated during the refrigerated storage (21 days). The related growth curves were compared with those obtained by a conventional third order predictive model obtaining a low agreement between observed and predicted data (Root Mean Squared Error = 1.77 for Aeromonas hydrophila and 0.64 for APC). The Lotka-Volterra interspecific competition model was used in order to calculate the degree of interaction between the two bacterial populations (\beta_{Ah/APC} and \beta{APC/Ah}, respectively, the interspecific competition coefficients of APC on Aeromonas hydrophila and vice-versa). Afterwards, the Lotka-Volterra equations were applied as tertiary predictive model, taking into account, simultaneously, the environmental fluctuations and the bacterial interspecific competition. This approach allowed to obtain a best fitting to the observed mean growth curves with a Root Mean Squared Error of 0.09 for Aeromonas hydrophila and 0.28 for APC. Finally, authors carry out some considerations about the necessary use of competitive models in the context of the new trends in predictive microbiology.Comment: 16 pages, 1 table, 2 figure