A Study of Connection Management Approaches for an impairment-aware Optical Control Plane

Abstract. Transparent optical networks need novel connection management approaches to take into account the presence of physical impairments in lightpath provisioning. Two main schemes are emerging from literature when considering how to introduce impairment-aware mechanisms in a distributed optical control plane like GMPLS. A well-known approach is based on extending the routing protocol to compute an optically-feasible light-path. Lately, a new approach is emerging which keeps the routing protocol unmodified while leveraging on signaling protocol extensions to find the proper lightpath for the incoming connection request. The aim of this paper is to prove that the signaling-based approach has several advantages compared to the routing-based one, in term of scalability and robustness especially when link information changes are frequent in the network. Simulation results show that a signaling-based approach is much more robust to inaccurate information about network status, therefore it is a suitable approach for considering physical impairments in dynamic optical networks

Characterization of the defective interaction between a subset of natural killer cells and dendritic cells in HIV-1 infection

In this study, we demonstrate that the in vitro interactions between a CD56neg/CD16pos (CD56neg) subset of natural killer (NK) cells and autologous dendritic cells (DCs) from HIV-1–infected viremic but not aviremic individuals are markedly impaired and likely interfere with the development of an effective immune response. Among the defective interactions are abnormalities in the process of reciprocal NK–DC activation and maturation as well as a defect in the NK cell–mediated editing or elimination of immature DCs (iDCs). Notably, the lysis of mature DCs (mDCs) by autologous NK cells was highly impaired even after the complete masking of major histocompatibility complex I molecules, suggesting that the defective elimination of autologous iDCs is at the level of activating NK cell receptors. In this regard, the markedly impaired expression/secretion and function of NKp30 and TNF-related apoptosis-inducing ligand, particularly among the CD56neg NK cell subset, largely accounts for the highly defective NK cell–mediated lysis of autologous iDCs. Moreover, mDCs generated from HIV-1 viremic but not aviremic patients are substantially impaired in their ability to secrete interleukin (IL)-10 and -12 and to prime the proliferation of neighboring autologous NK cells, which, in turn, fail to secrete adequate amounts of interferon-γ

Dendritic Cells/Natural Killer Cross-Talk: A Novel Target for Human Immunodeficiency Virus Type-1 Protease Inhibitors

BACKGROUND: HIV-1 Protease Inhibitors, namely PIs, originally designed to inhibit HIV-1 aspartic protease, can modulate the immune response by mechanisms largely unknown, and independent from their activity on viral replication. Here, we analyzed the ability of PIs to interfere with differentiation program of monocytes toward dendritic cell (DCs) lineage, a key process in the inflammatory response. METHODOLOGY/PRINCIPAL FINDINGS: Monocytes from healthy donors were isolated and induced to differentiate in vitro in the presence or absence of saquinavir, ritonavir, nelfinavir, indinavir or amprenavir (sqv, rtv, nlfv, idv, apv, respectively). These drugs demonstrated a differential ability to sustain the generation of immature DCs (iDCs) with an altered phenotype, including low levels of CD1a, CD86, CD36 and CD209. DCs generated in the presence of rtv also failed to acquire the typical phenotype of mature DCs (mDCs), and secreted lower amounts of IL-12 and IL-15. Accordingly, these aberrant mDCs failed to support activation of autologous Natural Killer (NK) cells, and resulted highly susceptible to NK cell-mediated cytotoxicity. CONCLUSIONS/SIGNIFICANCE: Our findings uncover novel functional properties of PIs within the DC-NK cell cross-talk, unveiling the heterogeneous ability of members of this class drugs to drive the generation of atypical monocyte-derived DCs (MDDCs) showing an aberrant phenotype, a failure to respond appropriately to bacterial endotoxin, a weak ability to prime autologous NK cells, and a high susceptibility to NK cell killing. These unexpected properties might contribute to limit inflammation and viral spreading in HIV-1 infected patients under PIs treatment, and open novel therapeutical perspectives for this class drugs as immunomodulators in autoimmunity and cancer

A Knowledge, Attitude, and Perception Study on Flu and COVID-19 Vaccination during the COVID-19 Pandemic: Multicentric Italian Survey Insights

In January 2020, Chinese health authorities identified a novel coronavirus strain never before isolated in humans. It quickly spread across the world, and was eventually declared a pandemic, leading to about 310 million confirmed cases and to 5,497,113 deaths (data as of 11 January 2022). Influenza viruses affect millions of people during cold seasons, with high impacts, in terms of mortality and morbidity. Patients with comorbidities are at a higher risk of acquiring severe problems due to COVID-19 and the flu-infections that could impact their underlying clinical conditions. In the present study, knowledge, attitudes, and opinions of the general population regarding COVID-19 and influenza immunization were evaluated. A multicenter, web-based, cross-sectional study was conducted between 10 February and 12 July 2020, during the first wave of SARS-CoV-2 infections among the general population in Italy. A sample of 4116 questionnaires was collected at the end of the study period. Overall, 17.5% of respondents stated that it was unlikely that they would accept a future COVID-19 vaccine (n = 720). Reasons behind vaccine refusal/indecision were mainly a lack of trust in the vaccine (41.1%), the fear of side effects (23.4%), or a lack of perception of susceptibility to the disease (17.1%). More than 50% (53.8%; n = 2214) of the sample participants were willing to receive flu vaccinations in the forthcoming vaccination campaign, but only 28.2% of cases had received it at least once in the previous five seasons. A higher knowledge score about SARS-CoV-2/COVID-19 and at least one flu vaccination during previous influenza seasons were significantly associated with the intention to be vaccinated against COVID-19 and influenza. The continuous study of factors, determining vaccination acceptance and hesitancy, is fundamental in the current context, in regard to improve vaccination confidence and adherence rates against vaccine preventable diseases

Recent results on heavy-ion induced reactions of interest for neutrinoless double beta decay at INFN-LNS

Abstract. The possibility to use a special class of heavy-ion induced direct reactions, such as double charge exchange reactions, is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay halflife. The methodology of the experimental campaign presently running at INFN - Laboratori Nazionali del Sud is reported and the experimental challenges characterizing such activity are describe

Hitless network re-optimization to reduce spectrum fragmentation in distributed GMPLS flexible optical networks

This paper presents a network re-optimization procedure moving the spectrum allocation of connections in a distributed fashion to defragment flexible optical networks, according to the proposed policies. Without changes to GMPLS standards, it improves network performance without traffic disruptions or excessive burdens for the control plane

Path-based Fragmentation Metric and RSA Algorithms for Elastic Optical Networks

Flexi-grid technology has emerged as the evolution of fixed-grid DWDM core optical networks, enabling more efficient utilization of spectral resources and leading to higher overall network throughput. However, it suffers from an aggravated form of the spectrum fragmentation problem that affects fixed-grid networks. This work presents a novel path-based metric to better evaluate the fragmentation of spectral resources in flexi-grid optical networks, which considers that not all links of a path may contain enough free frequency slots and the likelihood that an end-to-end spectral void is large enough to house a connection. Furthermore, two families of heuristic routing and spectrum allocation (RSA) algorithms that preventively attempt to minimize the value of an input fragmentation metric are presented. These are used to evaluate the effectiveness of multiple metrics, both introduced in this work and from the existing literature, via simulations. We find that both proposed families can perform better, in terms of blocking probability and achievable network throughput, than the well-known -shortest paths routing with a first fit spectrum allocation policy, with one of them trading performance for lower complexity, and that the proposed fragmentation metric outperforms the existing ones

Towards deployment of signalling based approaches for impairment aware lightpath setup in transparent WDM optical networks

We implement extensions to intrinsic functionality of standard RSVP-TE on a commercially available GMPLS protocol stack to setup optically feasible lightpaths and study the performance and deployment feasibility in real-world transparent WDM optical networks

Two euroversals in a global perspective : auxiliation and alignment

A number of studies in linguistic typology over the past few years have concentrated on what have come to be called ‘euroversals’. In this paper, I shall examine two of them, viz. accusative alignment and the occurrence of a ‘have’/‘be’ alternation in perfective auxiliation. Focusing on Romance dialects, I will show that thorough inspection of dialect variation in (a subset of) the languages of Europe provides crucial insights that have escaped so far the attention of typologists who dealt with these topics. The main results are that, firstly, alternation in perfective auxiliation is not accusatively aligned and, hence, the two euroversals at issue are mutually contradictory; and that, secondly, variation and change in perfective auxiliation across time and space in Romance reflects a shift in the alignment properties of the varieties at issue. More generally, the moral of the present discussion is that serious consideration of dialect variation is a necessary precondition for dispelling the commonplace that represents Europe as a rather dull linguistic landscape with very little structural diversity

Techniques to handle potential active lightpath(s) disruption due to crosstalk introduced by setup of new lightpath

We propose techniques to handle potential disruption of active lightpath(s) due to crosstalk introduced by setup of new lightpath. Simulation results suggest that suitable RSVP-TE extensions are sufficient for deployment in real traffic scenarios