A survey on OFDM-based elastic core optical networking

Orthogonal frequency-division multiplexing (OFDM) is a modulation technology that has been widely adopted in many new and emerging broadband wireless and wireline communication systems. Due to its capability to transmit a high-speed data stream using multiple spectral-overlapped lower-speed subcarriers, OFDM technology offers superior advantages of high spectrum efficiency, robustness against inter-carrier and inter-symbol interference, adaptability to server channel conditions, etc. In recent years, there have been intensive studies on optical OFDM (O-OFDM) transmission technologies, and it is considered a promising technology for future ultra-high-speed optical transmission. Based on O-OFDM technology, a novel elastic optical network architecture with immense flexibility and scalability in spectrum allocation and data rate accommodation could be built to support diverse services and the rapid growth of Internet traffic in the future. In this paper, we present a comprehensive survey on OFDM-based elastic optical network technologies, including basic principles of OFDM, O-OFDM technologies, the architectures of OFDM-based elastic core optical networks, and related key enabling technologies. The main advantages and issues of OFDM-based elastic core optical networks that are under research are also discussed

An innovative model for the sustainability of investments in the wind energy sector: the use of green sukuk in an Italian case study

In this paper we present the technical-energy-economic feasibility of wind power systems. An Italian 1 megawatt case study was considered to evaluate the importance of incentives in order to achieve the grid parity. Due to the severe reduction of incentives in the last years, in the present work we propose the use of Sukuk, a Shari’ah-compliant instrument used in the Islamic finance, as an alternative financial instrument used to limit the extent of leverage associated with financing. The building cost thresholds necessary to achieve the grid parity and a profitable and bankable project are presented with a sensitivity analysis. In the framework of the efforts against climate change and the emission of greenhouse gas, our results evidenced the importance of incentives and the applicability of the use of Shari’ah-compliant sukuk instruments in order to provide a feasible and sustainable investment in the wind energy sector

A database of immunoglobulins with integrated tools: DIGIT

The DIGIT (Database of ImmunoGlobulins with Integrated Tools) database (http://biocomputing.it/digit) is an integrated resource storing sequences of annotated immunoglobulin variable domains and enriched with tools for searching and analyzing them. The annotations in the database include information on the type of antigen, the respective germline sequences and on pairing information between light and heavy chains. Other annotations, such as the identification of the complementarity determining regions, assignment of their structural class and identification of mutations with respect to the germline, are computed on the fly and can also be obtained for user-submitted sequences. The system allows customized BLAST searches and automatic building of 3D models of the domains to be performed

Evaluating climate between working excellence and organizational innovation: What comes first?

This research introduces a new concept of organizational climate, seen as a "mediator", namely a factor liable to produce positive eects on both individual performances and on work processes and relations, thereby creating a favorable relationship between work excellence and organizational innovation. Health systems have been called to promote sustainability, as actors who work for the health and well-being of their patients. Starting from these considerations, this work shows the main results of a longitudinal study conducted in the pediatric department of a large hospital in southern Italy, for a period of three years (May 2014-May 2017). The reference survey was very broad because in the first step of the research a general questionnaire was adopted which included various aspects. Subsequently, the analysis of the influence of the "climate" factor was carried out according to a 3-dimensional scheme: structural, interpersonal/relational and individual. The focus was therefore set - especially in the second survey - on those indicators responding to the objective of the research and that were consistent with the epistemological choice made. The main scope was to verify the conditions according to which the organizational climate can emerge as a novel factor capable of siding with and orienting innovative patient-centered policies of human resources management

Risk analysis of Bacillus spp. isolated from cured pork sausages

This study was undertaken to acquire information about the toxigenic potential of Bacillus strains isolated from eight cured pork sausages obtained from traditional or industrial processings. The application of RAPD-PCR protocols made it possible to identify 52 different biotypes among 220 heat-resistant Gram-positive endospore-forming colonies. The sequence analysis of the 5’ region of 16S rDNA revealed that 36 strains belonged to B. subtilis and 16 to B. pumilus species. No strains belonging to B. cereus species were isolated from the cured sausages analysed. The toxigenic potential of these strains was assayed by PCR analysis and physiological tests to identify the most important B. cereus toxins and virulence factors. No specific PCR fragment was obtained from any of the strains; however, some of them were found positive for hemolytic and lecithinase activity.These preliminary results reassure about the microbiological risk related to the presence of pathogenic Bacillus strains in cured pork sausages analysed even though the hemolytic and lecithinase activities found in some strains suggest that more in-depth analyses need to be carried out

Smart working as an organisational process or as a social change? An Italian pandemic experience

Purpose: Along the coronavirus pandemic, huge business challenges are facing as a result of collapsing customer demand and organisational significant changes supported by digital development, while the increasing social and environmental needs involve business and individuals. The authors argue that this trend is modifying organisational and market logic, replacing them with values and practices linked to community-based models. The present work aims to study the impact that smart working (SW) has on the worker, seen both as a member of the organisation and the social community. Design/methodology/approach: The study data were collected from a computer-assisted web interview administered in 2020 to public employees working for health agencies across the Campania region, in South Italy. To test the conceptual model, partial least squares-structural equation modelling is used. Considering the abductive soul of the research, the study represents a pilot survey that will deliver stochastic results to be subsequently replicated in all Italian health agencies. Findings: The results of the research highlighted how the evolutionary dynamics of SW employees tend towards a reconceptualisation of workspaces, a redefinition of time and emotions and a better balance between work and personal life, thus creating a greater space for social and community aspects and determining a greater involvement in their working life. Originality/value: This research introduces a new win-win logic in the labour market, one capable of generating advantages for people, organisations and the entire social system by allowing workers to better reconcile working times with their personal needs and with flexibility demands coming from companies

Vertical MEMS Resonators for Real-Time Clock Applications

MEMS resonators are today widely investigated as a desirable alternative to quartz resonators in real-time clock applications, because of their low-cost, integration capability properties. Nevertheless, MEMS resonators performances are still not competitive, especially in terms of frequency stability and device equivalent resistance (and, then, power consumption). We propose a new structure for a MEMS resonator, with a vertical-like transduction mechanism, which exhibits promising features. The vertical resonator can be fabricated with the low-cost, high performance THELMA technology, and it is designed to be efficiently frequency tunable. With respect to the commonly investigated lateral resonators, it is expected to have lower equivalent resistances and improved large-scale repeatability characteristics

Microbial community dynamics during the Scamorza Altamurana cheese natural fermentation.

The growth dynamics of the natural microbial community responsible for the fermentation of Scamorza Altamurana, a typical Southern Italian cheese made using backslopping, was investigated applying a polyphasic approach combining 1) microbial enumeration with culture media, 2) randomly amplified polymorphic DNA (RAPD) fingerprinting of microbial communities, 3) sequencing of partial 16S ribosomal DNA (rDNA) genes, and 4) physiological tests. Viable cell counts on different culture media showed that the cocci community prevailed during the 18 h of curd fermentation and the 6 d of cheese ripening. RAPD fingerprinting made it possible to isolate 25 different strains identified by 16S rDNA sequencing as belonging to five species of Lactobacillus, three species of Streptococcus, one species of Weissella, and one species of Enterococcus. The physiological analyses of all lactic acid bacteria strains revealed that the isolates belonging to Streptococcus genus were the most acidifying, whereas lactobacilli were most proteolytic. Streptococcus thermophilus C48W and Lactobacillus delbrueckii subsp. bulgaricus B15Z dominated all through the fermentation process. Furthermore, they seemed to be stable in a subsequent whey sample analyzed after 7 mo. The recovery of strains endowed with interesting technological features, such as acidifying and proteolytic activities, and surviving in natural whey could allow the upscaling of cheese processing safeguarding the organoleptic characteristics of Scamorza Altamurana and could possibly improve other fermented dairy products

Can the current state support mechanisms help the growth of renewable energies in wind markets?

The aim of this paper is to provide evidence on the effectiveness of the current state support mechanism incentive adopted by the Italian government in the wind market. In particular, this paper intends to investigate the effectiveness of the auction mechanism as an incentive tool for renewable sources as required by the transposition of Directive 2009/28/EC. In order to demonstrate the economic and financial feasibility of a typical wind-sector investment, we performed a scenario analysis (Monte Carlo simulation) determining a 52,500 Net Present Value (NPV) by varying the key underlying variables of the investment. The results show that with the mechanism currently in place the percentage of positive leveraged NPV is approximately equal to 70%. Despite the state contribution provided through the “Feed-in tariff” mechanism, the profitability of wind projects is not always successful, and this problem could be amplified by the slowness of the authorization procedures. The article offers prime reflections for scholars and policy makers who have long been committed to promoting sustainable development and important considerations on the introduction of further incentive models