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Measurements of the gravitational constant G are notoriously difficult. Individual state-of-the-art experiments have managed to determine the value of G with high precision: although, when considered collectively, the range in the measured values of G far exceeds individual uncertainties, suggesting the presence of unaccounted for systematic effects. Here, we propose a Bayesian framework to account for the presence of systematic errors in the various measurement of G while proposing a consensus value, following two paths: a parametric approach, based on the maximum entropy principle, and a non-parametric one, the latter being a very flexible approach not committed to any specific functional form. With both our methods, we find that the uncertainty on this fundamental constant, once systematics are included, is significantly larger than what quoted in CODATA 2018. Moreover, the morphology of the non-parametric distribution hints towards the presence of several sources of unaccounted for systematics. In light of this, we recommend a consensus value for the gravitational constant G = 6. 6740 - 0.0015 + 0.0015 × 10 - 11 m 3 kg - 1 s - 2 . [ABSTRACT FROM AUTHOR]

• Intact HIV-1 proviruses decline rapidly after antiretroviral treatment initiation in infants. • Clonal expansion of intact proviruses can occur during early-stage antiretroviral treatment. • Viral rebound may be linked to intact proviruses integrated into genes. • Activating the chromatin marks proximal to the intact proviruses may promote viral rebound. The persistence of HIV-1-infected cells during antiretroviral therapy is well documented but may be modulated by early initiation of antiretroviral therapy in infants. Here, we longitudinally analyzed the proviral landscape in nine infants with vertical HIV-1 infection from Mozambique over a median period of 24 months, using single-genome, near full-length, next-generation proviral sequencing. We observed a rapid decline in the frequency of intact proviruses, leading to a disproportional under-representation of intact HIV-1 sequences within the total number of HIV-1 DNA sequences after 12-24 months of therapy. In addition, proviral integration site profiling in one infant demonstrated clonal expansion of infected cells harboring intact proviruses and indicated that viral rebound was associated with an integration site profile dominated by intact proviruses integrated into genic and accessible chromatin locations. Together, these results permit rare insight into the evolution of the HIV-1 reservoir in infants infected with HIV-1 and suggest that the rapid decline of intact proviruses, relative to defective proviruses, may be attributed to a higher vulnerability of genome-intact proviruses to antiviral immunity. Technologies to analyze combinations of intact proviral sequences and corresponding integration sites permit a high-resolution analysis of HIV-1 reservoir cells after early antiretroviral treatment initiation in infants. [ABSTRACT FROM AUTHOR]

The copious scientific literature produced after the detection of GW170817 electromagnetic counterpart demonstrated the importance of a prompt and accurate localization of the gravitational wave within the comoving volume. In this letter, we present figaro , a ready to use and publicly available software that relies on Bayesian non-parametrics. figaro is designed to run in parallel with parameter estimation algorithms to provide updated three-dimensional volume localization information. Differently from any existing algorithms, the analytical nature of the figaro reconstruction allows a ranking of the entries of galaxy catalogues by their probability of being the host of a gravitational wave event, hence providing an additional tool for a prompt electromagnetic follow up of gravitational waves. We illustrate the features of figaro on binary black holes as well as on GW170817. Finally, we demonstrate the robustness of figaro by producing so-called pp-plots and we present a method based on information entropy to assess when, during the parameter estimation run, it is reasonable to begin releasing skymaps. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is Available in the Text. Background: Virally suppressed chronic HIV-infected individuals on antiretroviral therapy experience similar immune impairments as HIV-uninfected elderly. However, they manifest symptoms of premature immune aging such as suboptimal responses to vaccination at a younger age. Mechanisms underlying premature immune aging are unclear. Setting: The study site was University of Miami Miller School of Medicine. Methods: In this study, we aimed to identify molecular signatures of aging in HIV-infected (HIV) individuals compared with age-matched healthy control (HC) participants. Transcriptomic profiles of peripheral blood mononuclear cells collected cross-sectionally from study participants were evaluated using RNA sequencing, and genes and pathways associated with age and HIV status were identified and compared between study groups. Generalized linear modeling was used to identify transcriptional signatures associated with age. Results: Despite that fewer differentially expressed genes between young (<40 yrs) and old (>59 yrs) were observed in the HIV group, metabolic and innate immune activation pathways were associated with increasing age in both HIV and HC. Age was also associated with pathways involved with T-cell immune activation in HC and with interferon signaling pathways in HIV. We observed signs of precocious immune aging at the transcriptional level in HIV and defined a transcriptional perturbation associated with innate immunity and glucose metabolism induced by aging in both HC and HIV. Conclusion: In this study, we identified distinct molecular signatures predictive of age in HIV versus HC, which suggest precocious immune aging in HIV. Overall, our results highlight the molecular pathways of immune aging in both HC and HIV that may be targeted for additional mechanistic insights or in a therapeutic setting. [ABSTRACT FROM AUTHOR]

The size of the latent HIV reservoir is associated with the timing of therapeutic interventions and overall health of the immune system. Here, we demonstrate that T cell phenotypic signatures associate with viral reservoir size in a cohort of HIV vertically infected children and young adults under durable viral control, and who initiated anti-retroviral therapy (ART) <2 years old. Flow cytometry was used to measure expression of immune activation (IA), immune checkpoint (ICP) markers, and intracellular cytokine production after stimulation with GAG peptides in CD4 and CD8 T cells from cross-sectional peripheral blood samples. We also evaluated the expression of 96 genes in sort-purified total CD4 and CD8 T cells along with HIV-specific CD4 and CD8 T cells using a multiplexed RT-PCR approach. As a measure of HIV reservoir, total HIV-DNA quantification by real-time PCR was performed. Poisson regression modeling for predicting reservoir size using phenotypic markers revealed a signature that featured frequencies of PD-1+CD4 T cells, TIGIT+CD4 T cells and HIV-specific (CD40L+) CD4 T cells as important predictors and it also shows that time of ART initiation strongly affects their association with HIV-DNA. Further, gene expression analysis showed that the frequencies of PD-1+CD4 T cells associated with a CD4 T cell molecular profile skewed toward an exhausted Th1 profile. Our data provide a link between immune checkpoint molecules and HIV persistence in a pediatric cohort as has been demonstrated in adults. Frequencies of PD-1+ and TIGIT+CD4 T cells along with the frequency of HIV-specific CD4 T cells could be associated with the mechanism of viral persistence and may provide insight into potential targets for therapeutic intervention. Author summary: Low HIV reservoir size is associated with positive outcomes of therapeutic approaches and better immune function. Here, we identified a 9-marker T cell immune signature based on phenotypic flow cytometry data that associated with total HIV DNA measurements in a pediatric cohort of 34 perinatally infected participants with sustained viral control. Notably, frequencies of PD-1+ CD4 T cells and TIGIT+ CD4 T cells were positively correlated and HIV-specific (CD40L+) CD4 T cells were negatively correlated with HIV DNA, and were impacted by time of ART initiation. Gene expression analysis by multiplex RT-PCR showed that the frequencies of PD-1+ CD4 T cells associated with an exhausted Th1 molecular profile in CD4 T cells. This signature could inform future therapeutic studies and provide mechanistic insight on HIV persistence in perinatally infected HIV. [ABSTRACT FROM AUTHOR]

In this article, a noninvasive remote monitoring method of error of electricity energy meter (EM) is introduced and its achievable precision is investigated. The aim of the method is to determine remotely the smart EM active power relative measurement error using the reference EM connected at the input of a low-voltage distribution grid segment. The meter error estimation is carried out despite other customers’ electrical load changes observable by the reference meter and power fluctuations in the distribution network. The method is based on the real-time analysis of natural customer power consumption profiles without any additional load injection for error-monitoring needs. A power step in the customer power consumption profile is detected by the meter under test and then the step magnitude is delivered for the comparison with the power step magnitude estimated synchronously by the reference meter. The analysis of the method error is conducted by applying simulation of the benchmark distribution grid which includes 26 EMs and utilizing the open data power consumption profiles. It is shown that after two to three days of averaging (including approximately 170 power steps) of the meter error estimates, it becomes possible to achieve an uncertainty of meter error estimation approximately 0.63%. The feasibility of the method implementation scenarios with the state-of-the-art EM data collection protocols in advanced measurement infrastructure (AMI) by means of occupancy index modeling is performed. [ABSTRACT FROM AUTHOR]

The monitoring and the management of smart grid require an advanced communication infrastructure. The time synchronization is among the most important services such an infrastructure should offer. Several solutions are available to disseminate the time information in a distributed system; for instance, most of the times a global positioning system (GPS) receiver is used to recover accurate time information. However, GPS receivers need a clear view of the sky. Other solutions, like the use of a network-based synchronization mechanism, require a dedicated communication infrastructure, which is not always feasible for economical reason. Thus, the use of the power grid itself to disseminate a time signal is extremely interesting. The aim of this article is to investigate the possibility to distribute a time signal over a medium voltage (MV) grid using a chirp-based modulation. The timing data are coded using IRIG-B time code. Such an approach does not require the installation of a dedicated infrastructure, and it is noninvasive, because the signal is transmitted on a different band with the respect to power line communication (PLC). The effectiveness of the approach has been experimentally evaluated on a test MV line available in a laboratory. Although the tested chirp-based symbol has a limited frequency bandwidth (80 kHz), the jitter in the identification of the start of frame is on the order of 7.5 $\mu \text{s}$ , fulfilling the requirements of the most smart grid applications. [ABSTRACT FROM AUTHOR]

Early initiation of antiretroviral therapy (ART) in vertically HIV-infected children limits the size of the virus reservoir, but whether the time of treatment initiation (TI) can durably impact host immune responses associated with HIV infection is still unknown. This study was conducted in PBMC of 20 HIV-infected virally suppressed children on ART (mean age 9.4 y), classified as early treated (ET; age at ART initiation ≤0.5 y, n =14) or late treated (LT; age at ART initiation 1-10 y, n = 6). Frequencies and functions of Ag-specific CD4 (CD40L+) and CD8 (CD69+) T cells were evaluated by intracellular IL-2, IFN-γ, and TNF-α production with IL-21 in CD4 or CD107a, granzyme B and perforin in CD8 T cells following stimulation with HIV gp140 protein (ENV) or GAG peptides by multiparameter flow cytometry. ET showed a higher proportion of cytokine-producing ENV- and GAG-specific CD4 and CD8 T cells compared with LT. In particular, ET were enriched in polyfunctional T cells. RNA sequencing analysis showed upregulation of immune activation pathways in LT compared with ET. Our results suggest that timing of TI in HIV-infected children has a long-term and measurable impact on the quality of the HIV-specific T cell immune responses and transcriptional profiles of PBMC, reinforcing the importance of early TI. [ABSTRACT FROM AUTHOR]

The increasing presence of intermittent distributed generation (DG) based on renewable energy sources (RESs) is heavily affecting the operation and management of modern distribution grids. Even though the use of distributed energy storage systems (DESSs) and the integration of advanced demand response (DR) programs are expected to mitigate this problem, security, safety, economic, and technical reasons are limiting the tests of these mechanisms in working systems. The test in simulation and emulation environments has proved to be an effective solution for the development of advanced control and protection schema, but their use for the simulation of the typically unpredictable behavior of end-users seems at least questionable. This paper proposes a testing framework for the analysis of experimental control strategies of distributed energy systems. The framework, based on a service-oriented architecture, can be easily interconnected to different systems, including renewable generators and storage systems. This framework can be used to analyze the performance of real energy systems, working in near-to-real conditions. The framework has been used for a pilot test on a subset of the facilities of the eLUX laboratory of the University of Brescia. The proposed framework allows analyzing the energy performance of this system by means of proper key performance indicators (KPIs). The efficiency analysis of a battery energy storage system (BESS) is presented, by proposing KPIs to evaluate the effect of different control strategies. Further KPIs are also used to evaluate the effectiveness of the BESS for improving the energy self-consumption of a photovoltaic system. [ABSTRACT FROM AUTHOR]

In this article, a noninvasive remote monitoring method of error of electricity energy meter (EM) is introduced and its achievable precision is investigated. The aim of the method is to determine remotely the smart EM active power relative measurement error using the reference EM connected at the input of a low-voltage distribution grid segment. The meter error estimation is carried out despite other customers’ electrical load changes observable by the reference meter and power fluctuations in the distribution network. The method is based on the real-time analysis of natural customer power consumption profiles without any additional load injection for error-monitoring needs. A power step in the customer power consumption profile is detected by the meter under test and then the step magnitude is delivered for the comparison with the power step magnitude estimated synchronously by the reference meter. The analysis of the method error is conducted by applying simulation of the benchmark distribution grid which includes 26 EMs and utilizing the open data power consumption profiles. It is shown that after two to three days of averaging (including approximately 170 power steps) of the meter error estimates, it becomes possible to achieve an uncertainty of meter error estimation approximately 0.63%. The feasibility of the method implementation scenarios with the state-of-the-art EM data collection protocols in advanced measurement infrastructure (AMI) by means of occupancy index modeling is performed. [ABSTRACT FROM AUTHOR]

The monitoring and the management of smart grid require an advanced communication infrastructure. The time synchronization is among the most important services such an infrastructure should offer. Several solutions are available to disseminate the time information in a distributed system; for instance, most of the times a global positioning system (GPS) receiver is used to recover accurate time information. However, GPS receivers need a clear view of the sky. Other solutions, like the use of a network-based synchronization mechanism, require a dedicated communication infrastructure, which is not always feasible for economical reason. Thus, the use of the power grid itself to disseminate a time signal is extremely interesting. The aim of this article is to investigate the possibility to distribute a time signal over a medium voltage (MV) grid using a chirp-based modulation. The timing data are coded using IRIG-B time code. Such an approach does not require the installation of a dedicated infrastructure, and it is noninvasive, because the signal is transmitted on a different band with the respect to power line communication (PLC). The effectiveness of the approach has been experimentally evaluated on a test MV line available in a laboratory. Although the tested chirp-based symbol has a limited frequency bandwidth (80 kHz), the jitter in the identification of the start of frame is on the order of 7.5 $\mu \text{s}$ , fulfilling the requirements of the most smart grid applications. [ABSTRACT FROM AUTHOR]

An efficient energy management requires an exchange of information among different energy grids, such as electricity, gas, and heating. This paper analyzes the open metering system (OMS), a set of protocols used to provide the communication in a multiutility grid, with special focus on its capability of distributing the time information over the infrastructure. Currently, synchronization accuracy on the order of seconds is more than enough for the traditional metering applications, while more advanced power quality and monitoring systems may require synchronization on the order of hundreds of microsecond or less (as stated by the national and international normative for dynamically controlling loads or renewable power generator on the local microgrid). In this paper, advantages and limits of the current standard, when wireless M-bus (wM-bus) is used as a physical layer, are highlighted by means of the analysis of the synchronization uncertainty sources, and by the experimental evaluation. Next, a custom synchronization method is applied for the first time, since the current OMS standard does not propose any solutions. The analysis and the experimental characterization indicate that the synchronization limit on the last-mile segment of wM-bus, using off-the-shelf components, is on the order of 1.8 $\mu \text{s}$. The proposed methodology can easily be extended to other communication protocols adopting similar architectures. [ABSTRACT FROM AUTHOR]

The smart grid (SG) approach is based on a strong interaction between the network communication infrastructure and the power grid. Usually the management of the infrastructure is done by the distribution system operators (DSOs) that are worried about the increasing managing complexity due to the presence of increasing number of distributed energy resources and electrical vehicles. The use of software-defined networking (SDN) may simplify the network configuration and management for DSO, as highlighted from previous research works. The objective of this paper is to introduce and characterize an internet protocol (IP)-based communication architecture with specialized SDN bridges operating also over narrowband power line communication (PLC) to reach the last mile applications (e.g., smart meters and inverters). The feasibility of this approach depends on the communication performance of the supervisory level used to dynamically configure the SDN bridges. The characterization of this level is done using the following performance indicators: the round trip time (RTT), the packet loss (PL) ratio, and the actual IP throughput. The experimental results show the feasibility of the proposed architecture, since the limitations are given only by the physical implementation of the PLC modem. In detail, results of the case study show that the minimum RTT is on the order of 30 ms, the PL ratio is always less than 1.7% and the maximum throughput is of 95 Mbit/s, fully compatible with the requirements of the applications. [ABSTRACT FROM AUTHOR]

Construction is known as one of the most dangerous industries in terms of worker safety. Collisions due the excessive proximity of workers to moving construction vehicles are one of the leading causes of fatal and non-fatal accidents on construction sites internationally. Proximity warning systems (PWS) have been proposed in the literature as a solution to detect the risk for collision and to alert workers and equipment operators in time to prevent collisions. Although the role of sensing technologies for situational awareness has been recognised in previous studies, several factors still need to be considered. This paper describes the design of a prototype sensor-based PWS, aimed mainly at small and medium-sized construction companies, to collect real-time data directly from construction sites and to warn workers of a potential risk of collision accidents. It considers, in an integrated manner, factors such as cost of deployment, the actual nature of a construction site as an operating environment and data protection. A low-cost, ultra-wideband (UWB)-based proximity detection system has been developed that can operate with or without fixed anchors. In addition, the PWS is compliant with the General Data Protection Regulation (GDPR) of the European Union. A privacy-by-design approach has been adopted and privacy mechanisms have been used for data protection. Future work could evaluate the PWS in real operational conditions and incorporate additional factors for its further development, such as studies on the timely interpretation of data. [ABSTRACT FROM AUTHOR]

Distributed measurement and control systems often rely on time synchronization protocols over Ethernet. Recently, it has been shown that estimating and compensating for not only time offsets, but also frequency skews is of crucial importance to meet the accuracy requirements of high-end applications. In this respect, this paper presents a new technique capable of: 1) measuring the jitter of multiple reference signals received by a single node over different network paths and 2) combining them in order to synthesize a downstream signal with a more stable frequency than using a single reference. The proposed algorithm can exploit the native frequency transport of Synchronous Ethernet and relies on a module for outlier identification and removal, a Kalman filter, and a linear quadratic regulator that drives a local voltage-controlled oscillator. The algorithm performance has been evaluated through both simulations and experiments using a prototype platform based on a field-programmable gate array. Simulation and experimental results confirm that the proposed approach can strongly decrease the jitter and wander of the generated signal. For instance, the time deviation is reduced on average by about 30% when three stable input references are merged and by several orders of magnitude when one of the input signals is affected by a large frequency step. [ABSTRACT FROM AUTHOR]

The business of distribution system operators is rapidly evolving as the distribution grid is hosting more distributed energy resources. Technology for monitoring, control, and protecting the grid is progressively pervading the lower segment of the network. These changes require a performing communication infrastructure to enable data exchange among the control centers of the grid. The 7th Framework Program European Project INTEGRIS proposes a hybrid infrastructure—based on broadband power line (BPL), Wi-Fi, and fiber optics (FO)—to enable services for grid management. This mix of technologies provides a balanced tradeoff between investments and benefits, meeting most of the requirements of the smart grid. This paper investigates the technologies that could be adopted and describes the experimental assessment performed in an operational environment in Italy. Using this installation, transfer time, time synchronization accuracy, dependability, and throughput are evaluated and analyzed over a long-term campaign. Results show that the FO is the best communication media, able to provide a two-way latency of 3 ms (95 percentile), whereas BPL has a two-way latency of 57 ms (95 percentile —4 hops). Those results confirm that a careful selection of the technologies is required to satisfy requirements of smart grid. [ABSTRACT FROM PUBLISHER]

Power line communication (PLC) seems to be one of the best trade-off between cost and benefit for implementing Smart Grids in industrial context. Unfortunately, industrial environment may compromise the reliability of PLC technologies due to noisy communication channel and interfering/competing PLC systems. In this work, a multi-protocol instrument for PLC performance estimation is presented. The proposed solution is able to characterize and to decode several PLC systems with different physical modulations using a software-defined architecture. A working prototype of the proposed instrument has been characterized and used in a real industrial plant in order to study potential issues affecting PLC. [ABSTRACT FROM AUTHOR]

Highlights: [•] HIV+ patients had protective HI titers prior to vaccination and did not seroconvert. [•] Influenza-specific memory B-cell responses were detected by B-cell ELISpot in HIV+. [•] Decreasing antibody but not memory B-cell responses are in HIV+ vaccinated yearly. [Copyright &y& Elsevier]

Cyclosporin A (CsA) is an effective therapy for children with long-lasting nephrotic syndrome (NS). Long-term treatment can result in chronic CsA nephropathy (CsAN) and there is controversy concerning its incidence and severity. Trough levels are commonly used to monitor the drug concentration. We report a retrospective clinical and histological analysis of 18 children (12 males, 6 females) with steroid-dependent nephrotic syndrome (15 patients) and partially steroid-sensitive nephrotic syndrome (3 patients) treated with CsA for a long-term period (mean 4.9 years, range 2.2-6.9). Before CsA treatment all patients had normal creatinine clearance. CsA was started at a dose of 5 mg/kg per day administered orally in two divided doses and adjusted to maintain the mean CsA blood concentration between 250 and 350 ng/ml obtained from abbreviated area under the curve (AUC). A renal biopsy was performed after a mean period of 3.9 years (range 2.2-6.2) from the start of CsA treatment. Tubular, interstitial, and arteriolar lesions were evaluated in order to assess CsAN. The mean CsA dose and the mean CsA blood concentration were 4.4 mg/kg per day (range 3.6-5.8) and 276.6 ng/ml (range 162-346), respectively. No child had a worsening creatinine clearance during CsA treatment and follow-up after CsA discontinuation. If compared with the year before the start of CsA treatment, NS relapses and prednisone (PDN) dose significantly decreased during CsA treatment, 4/year versus 0.8/year (P<0.0001) and 0.9 mg/kg per day versus 0.2 mg/kg per day (P<0.0001), respectively. Histological analysis showed 15 patients with minimal change disease and 3 with focal segmental glomerulosclerosis. Clear-cut lesions diagnostic of CsAN were never found and only mild lesions were observed in 5 children (suggestive of CsAN in 2 patients and consistent with CsAN in 3 patients). Long-term CsA treatment is confirmed to be effective in preventing NS relapses and reducing PDN dose. Renal function is not a reliable indicator of CsAN. With the mean CsA blood concentrations used in our patients CsAN presented a low incidence (28%) and was generally mild. Renal biopsy should be performed 2-3 years from the start of long-term CsA treatment, especially if the mean CsA blood concentrations are not regularly monitored. [ABSTRACT FROM AUTHOR]

The management of the distribution network is becoming increasingly important as the penetration of distributed energy resources is increasing. Reliable knowledge of the real-time status of the network is essential if algorithms are to be used to help distribution system operators define network configurations. State Estimation (SE) algorithms are capable of producing such an accurate snapshot of the network state but, in turn, require a wide range of information, e.g., network topology, real-time measurement and power profiles from customers/productions. Those profiles which may, in principle, be provided by smart meters are not always available due to technical limitations of existing Advanced Metering Infrastructure (AMI) in terms of communication, storage and computing power. That means that power profiles are only available for a subset of customers. The paper proposes an approach that can overcome these limitations: the remaining profiles, required by SE algorithms, are generated on the basis of customer-related information, identifying clusters of customers with similar features, such as the same contract and pattern of energy consumption. For each cluster, a power profile estimator is generated using long-term power profiles of a limited sub-set of customers, randomly selected from the cluster itself. The synthesized full power profile, representing each customer of the distribution network, is then obtained by scaling the power profile estimator of the cluster to which the customer belongs, by the monthly energy exchanged by that customer, data that are easily available. The feasibility of the proposed approach was validated considering the distribution grid of Unareti SpA, an Italian Distribution System Operator (DSO), operating in northern Italy and serving approximately one million customers. The application of the proposed approach to the actual infrastructure shows some limitations in terms of the accuracy of the estimation of the power profile of the customer. In particular, the proposed methodology is not fully able to properly represent clusters composed of customers with a large variability in terms of power exchange with the distribution network. In any case, the root mean square error of the synthesized full power profile with the respect to validation power profiles belonging to the same cluster is, in the worst case, on the order of 6.3%, while in the rest of cases is well below 5%. Thus, the proposed approach represents a good compromise between accuracy in representing the behavior of customers on the network and resources (in terms of computational power, data storage and communication resources) to achieve that results. [ABSTRACT FROM AUTHOR]

Standard sirens have been the central paradigm in gravitational‐wave cosmology so far. From the gravitational wave signature of compact star binaries, it is possible to measure the luminosity distance of the source directly, and if additional information on the source redshift is provided, a measurement of the cosmological expansion can be performed. This review article discusses several methodologies that have been proposed to use gravitational waves for cosmological studies. Methods that use only gravitational‐wave signals and methods that use gravitational waves in conjunction with additional observations such as electromagnetic counterparts and galaxy catalogs will be discussed. The review also discusses the most recent results on gravitational‐wave cosmology, starting from the binary neutron star merger GW170817 and its electromagnetic counterpart and finishing with the population of binary black holes, observed with the third Gravitational‐wave Transient Catalog GWTC–3. [ABSTRACT FROM AUTHOR]

In this paper a general model for the estimation of the uncoordinated charging costs of Electric Vehicles (EVs) in the presence of distributed and intermittent generation, and variable electricity tariffs is presented. The proposed method aims at estimating the monthly average cost of uncoordinated charging of a single EV depending on the hour at which the EV is plugged into the EV Supply Equipment (EVSE). The feasibility and relevance of the proposed model is verified by applying the considered cost estimation method to a suitable use case. A single EV charging service offered at a public building equipped with a Photovoltaic (PV) system has been considered as reference case. The proposed model has been applied to the PV production and loads consumption data collected during one year, and the results of the study compared with the Time-Of-Use (TOU) electricity tariff. The application of the proposed model identified noticeable deviations among the computed EV charging costs and the reference TOU profile, with differences up to 40%, depending on the considered month and on the time of charging during the day. It can be concluded that such model could be used to properly detect opportunities of energy savings, and to define dedicated EV price signals that could help to promote the optimal use of distributed energy resources. [ABSTRACT FROM AUTHOR]

Galactic binary neutron stars (BNSs) are a unique laboratory to probe the evolution of BNSs and their progenitors. Here, we use a new version of the population synthesis code sevn to evolve the population of Galactic BNSs, by modelling the spin up and down of pulsars self-consistently. We analyse the merger rate |$\mathcal {R}_{\rm MW}$|⁠ , orbital period P orb, eccentricity e , spin period P , and spin period derivative |$\dot{P}$| of the BNS population. Values of the common envelope parameter α = 1−3 and an accurate model of the Milky Way star formation history best reproduce the BNS merger rate in our Galaxy (⁠|$\mathcal {R}_{\rm MW}\approx {}30$| Myr−1). We apply radio-selection effects to our simulated BNSs and compare them to the observed population. Using a Dirichlet process Gaussian mixture method, we evaluate the four-dimensional likelihood in the |$(P_{\rm orb}, e, P, \dot{P})$| space, by comparing our radio-selected simulated pulsars against Galactic BNSs. Our analysis favours an uniform initial distribution for both the magnetic field (1010−13 G) and the spin period (10−100 ms). The implementation of radio selection effects is critical to match not only the spin period and period derivative, but also the orbital period and eccentricity of Galactic BNSs. According to our fiducial model, the Square Kilometre Array will detect ∼20 new BNSs in the Milky Way. [ABSTRACT FROM AUTHOR]

The rising concerns about global warming and environmental pollution are increasingly pushing towards the replacement of road vehicles powered by Internal Combustion Engines (ICEs). Electric Vehicles (EVs) are generally considered the best candidates for this transition, however, existing power grids and EV management systems are not yet ready for a large penetration of EVs, and the current opinion of the scientific community is that further research must be done in this field. The so-called Vehicle-to-Grid (V2G) concept plays a relevant role in this scenario by providing the communication capabilities required by advanced control and Demand-Side Management (DSM) strategies. Following this research trend, in this paper the communication requirements for the DSM of EVs in urban environments are discussed, by focusing on the mobile communication among EVs and smart grids. A specific system architecture for the DSM of EVs moving inside urban areas is proposed and discussed in terms of the required data throughput. In addition, the use of a Low-Power Wide-Area Network (LPWAN) solution—the Long-Range Wide Area Network (LoRaWAN) technology—is proposed as a possible alternative to cellular-like solutions, by testing an experimental communication infrastructure in a real environment. The results show that the proposed LPWAN technology is capable to handle an adequate amount of information for the considered application, and that one LoRa base station is able to serve up to 438 EVs per cell, and 1408 EV charging points. [ABSTRACT FROM AUTHOR]

Antigen-primed cluster of differentiation (CD) 4+ T follicular helper (Tfh) cells interact with B cells in the germinal centers (GCs) of lymph nodes to generate vaccine-induced antibody (Ab) responses. In the circulation, peripheral Tfh (pTfh) cells, a subset of memory CD4 T cells, serve as surrogates for GC Tfh because of several functional and phenotypic similarities between them. We investigated features of H1N1 influenza antigen-specific pTfh (Ag.pTfh) in virologically controlled HIV+ volunteers on antiretroviral therapy (ART) and healthy control (HC) participants selected from a seasonal influenza vaccine responsiveness study. Selection of the participants was made based on age, defined as young (18–40 y) and old (>60 y) and on their classification as a vaccine responder (VR) or vaccine nonresponder (VNR). VRs demonstrated expansion of CD40L+ and CD69+ Ag.pTfh, with induction of intracellular interleukin 21 (IL-21) and inducible costimulator (ICOS) post vaccination; these responses were strongest in young HC VRs and were less prominent in HIV+ individuals of all ages. Ag.pTfh in VNRs exhibited dramatically different characteristics from VRs, displaying an altered phenotype and a cytokine profile dominated by cytokines IL-2, tumor necrosis factor alpha (TNF-α), or IL-17 but lacking in IL-21. In coculture experiments, sorted pTfh did not support the B cell IgG production in VNRs and were predominantly an inflammatory T helper 1 (Th1)/T helper 17 (Th17) phenotype with lower ICOS and higher programmed cell death protein 1 (PD1) expression. IL-21 and ICOS on Ag.pTfh cells are negatively affected by both aging and HIV infection. Our findings demonstrate that dysfunctional Ag.pTfh cells with an altered IL-21/IL-2 axis contribute to inadequate vaccine responses. Approaches for targeting inflammation or expanding functional Tfh may improve vaccine responses in aging and those aging with HIV infection. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) approach relies on the use of the Internet Protocol (IP) as a pervasive network protocol. IP acts as a "glue" for interconnecting end devices (on the field side) and end users, leveraging on very diverse lower-level and upper-level protocols. The need for scalability would suggest the adoption of IPv6, but the large overhead and payloads do not match with the constraints dictated by common wireless solutions. For this reason, compression strategies have been proposed to avoid redundant information in the IPv6 header and to provide fragmentation and reassembly of long messages. For example, the Static Context Header Compression (SCHC) protocol has been recently referenced by the LoRa Alliance as a standard IPv6 compression scheme for LoRaWAN-based applications. In this way, IoT end points can seamlessly share an end-to-end IP link. However, implementation details are out of the specifications' scope. For this reason, formal test procedures for comparing solutions from different providers are important. In this paper, a test method for assessing architectural delays of real-world deployments of SCHC-over-LoRaWAN implementations is presented. The original proposal includes a mapping phase, for identifying information flows, and a subsequent evaluation phase, in which flows are timestamped and time-related metrics are computed. The proposed strategy has been tested in different use cases involving LoRaWAN backends deployed all around the world. The feasibility of the proposed approach has been tested by measuring the end-to-end latency of IPv6 data in sample use cases, obtaining a delay of less than 1 s. However, the main result is the demonstration that the suggested methodology permits a comparison of the behavior of IPv6 with SCHC-over-LoRaWAN, allowing the optimization of choices and parameters during deployment and commissioning of both infrastructure components and software. [ABSTRACT FROM AUTHOR]

Psychosocial support (PSS) to caregivers of HIV-infected infants on antiretroviral treatment (ART) is crucial to ensure ART adherence and sustained long-term viral suppression in children. A specific approach including tools to monitor and understand adherence behavior and risk factors that prevent optimal treatment compliance are urgently needed. This qualitative exploratory study, conducted in southern Mozambique, monitored the infants' viral response trajectories during 18 months follow-up, as a measure of adherence, reviewed the caregiver's PSS session notes and the answers to a study questionnaire, to analyze whether the standard PSS checklist applied to infants' caregivers can identify barriers influencing their adherence. Only 9 of 31 infants had sustained virologic response. Reported factors affecting adherence were: difficulties in drugs administration, shared responsibility to administer treatment; disclosure of child's HIV status to family members but lack of engagement; mother's ART interruption and poor viral response. In conclusion, we found that the standard PSS approach alone, applied to caregivers, was lacking focus on many relevant matters that were identified by the study questionnaire. A comprehensive patient-centered PSS package of care, including an adherence risk factor monitoring tool, tailored to caregivers and their children must be developed. [ABSTRACT FROM AUTHOR]

Response to seasonal influenza vaccination is currently evaluated by antibody correlates that estimate vaccine seroconversion as well as immune protection. These correlates rely on the general dogmas surrounding seasonal influenza vaccination; that is, that vaccine-induced antibodies would exclusively generate immunity to influenza vaccine strains and that protective immunity would wane before the next season. Here, we summarize recently reported data on immunity to seasonal influenza in healthy individuals and rediscuss results on yearly vaccinated pediatric immunocompromised patients that together highlight the need for revision of the current correlates of vaccine response to shift from quantitative to qualitative measurements. [ABSTRACT FROM AUTHOR]

The present study was aimed at investigating the role of coping strategies in predicting emotional distress following breast cancer, over and above the illness severity, operationalized in terms of the type of surgery performed. In order to achieve this goal, two groups of newly diagnosed breast cancer women were selected and compared on the basis of the type of surgical treatment received. A subsample of 30 women with quadrantectomy and sentinel lymph-node biopsy (SLNB) and a subsample of 31 patients with mastectomy and axillary dissection (MAD) filled in the Brief Cope scale and Hospital Anxiety and Depression Scale. Summarizing, results showed that emotional support, venting, and humor explained a statistically significant increment of variance in psychological distress indices. Implication for clinical practice and future research were discussed. [ABSTRACT FROM AUTHOR]

Industrial networks for distributed monitoring, control, and automation purposes require high-accuracy clock synchronization in topologies including long chains of cascaded nodes. Unfortunately, accuracy typically degrades as the number of devices and the distance from the synchronization reference node (i.e., the master or grandmaster) grows, because of the accumulation of multiple uncertainty contributions. To mitigate this problem, the so-called transparent clocks are used in some synchronization protocols, such as the precision transparent clock protocol used in PROFINET IO isochronous real time networks and the precision time protocol version 2, standardized as IEEE 1588–2008. In this paper, an optimal servo-clock in the mean square sense is proposed. The controller relies on both a Kalman filter that estimates the clock state difference with respect to the master and a static-state feedback assuring mean square stability even under the effect of significant fluctuations of the synchronization period. Several multiparametric simulation results in a case study based on the features of PROFINET IO devices confirm that excellent performance can be achieved with the proposed approach. [ABSTRACT FROM PUBLISHER]

Introduction: Persistence of HIV‐1, causing chronic immune activation, is a key determinant of premature senescence. Early antiretroviral therapy (ART) has been associated with a reduced HIV‐1 reservoir in children with perinatally acquired HIV‐1 (PHIV), but its impact on the senescence process is an open question. We investigated the association between HIV‐1 reservoir and biological and immune ageing profile in PHIV enrolled in the multicentre cross‐sectional study CARMA (Child and Adolescent Reservoir Measurements on early suppressive ART) conducted within the EPIICAL (Early treated Perinatally HIV Infected individuals: Improving Children's Actual Life) consortium. Methods: Between September 2017 and June 2018, CARMA enrolled 40 PHIV who started ART before 2 years of age and had undetectable viremia for at least 5 years before sampling date. Samples from 37 children with a median age of 13.8 years were available for this study. HIV‐1 DNA copies on CD4 cells, relative telomere length (marker of cellular senescence) and levels of T‐cell receptor rearrangement excision circle (TREC, marker of thymic output) on CD4 and CD8 cells were quantified by qPCR. Immunological profile was assessed by flow cytometry. Associations between molecular and phenotypic markers, HIV‐1 reservoir and age at ART initiation were explored using a multivariable Poisson regression. Results: Higher HIV‐1 reservoir was associated (p<0.001) with telomere shortening (incidence rate ratio [IRR] = 0.15 [0.13–0.17]), immunosenescence (CD28–CD57+, IRR = 1.23 [1.21–1.26]) and immunoactivation (CD38+ HLADR+, IRR = 7.29 [6.58–8.09]) of CD4 cells. Late ART initiation (after 6 months of age) correlated with higher HIV‐1 reservoir levels (552 [303–1001] vs. 89 [56–365] copies/106 CD4 cells, p = 0.003) and percentage of CD4 senescent cells (2.89 [1.95–6.31] vs. 1.02 [0.45–2.69, p = 0.047). TREC levels in CD8 cells were inversely associated with HIV‐1 reservoir (IRR = 0.77 [0.76–0.79]) and were significantly lower in late treated PHIV (1128 [486–1671] vs. 2278 [1425–3314], p = 0.042). Conclusions: Later ART initiation is associated with higher HIV‐1 reservoir size, which correlates with increased telomere shortening and senescence of CD4 cells. Timing of ART initiation in infancy has long‐term consequences on the immune and biological ageing profile of children with perinatally acquired HIV‐1. [ABSTRACT FROM AUTHOR]

Over the past few decades, centralized computing systems have been replaced by decentralized systems, consisting of simple nodes interconnected by a communication network. The time reference of the distributed nodes must be synchronized in order to be able to coordinate the operation or compare the data collected by the different nodes. Several synchronization protocols have been developed to be used instead of global positioning system or dedicated synchronization systems. For example, the network time protocol (NTP) is a very popular synchronization protocol used to synchronize computers over wide area networks, like the Internet. In addition, IEEE 1588, a synchronization protocol dedicated to high-performance synchronization in local networks, was recently established. However, submicroseconds synchronization can be obtained only using dedicated hardware devices, thereby increasing the cost of each node. For these reasons, PTP software-only implementations are quite common in real systems, with a resulting synchronization uncertainty varying from a few to hundreds of microseconds and quite burdensome to estimate or measure. The work presented in this paper focuses on the analysis of the major uncertainty contributions in a software-only implementation. Particularly, a careful analysis of timestamp mechanism and time management in a PC platform is carried out. In addition, a method for the experimental evaluation of uncertainty contributions is proposed. A test case based on a software implementation of the IEEE 1588 (the so-called PTPd) is presented. The experimental tests presented in the paper highlight that the main uncertainty source of a software-only synchronization approach is the timestamp method. Timestamping accuracy can be affected by the computational load of the node itself: in normal conditions, the maximum uncertainty introduced by the timestamp mechanism is in the order of 10 \mu\s, but in case of high computational load, it can raise up to 224 \mu\s. [ABSTRACT FROM AUTHOR]

In this study we compared patient and technique survival of 163 new hemodialysis (HD) patients (age 11.4±3.1 years) and 295 peritoneal dialysis patients (7.7±4.8 years. P< 0.001), treated in 23 dialysis centers participating in the Italian Registry of Pediatric Chronic Peritoneal Dialysis (CPD) during the years 1989–2000. Three HD (1.8%) and 17 CPD (5.8%) patients died; the overall average death rate was 9.8/1,000 patient-years in HD and 29.8/1,000 patient-years in CPD patients. No statistically significant difference in patient survival between CPD and HD was found, while the survival of 102 CPD children younger than 5 years at the start of dialysis was lower (P=0.0001) than that of 193 CPD and 160 HD patients aged 5–15 years. We registered 12 modality failures among HD (7.4%) patients and 44 among CPD (14.9%) patients. The main causes were vascular access failure and patient choice in HD, and infection in CPD patients. Technique survival was lower (P=0.007) in CPD than in HD patients; a statistically significant difference (P=0.01) was also observed between both the 0- to 5- and the 5- to 15-year-old CPD patients and the HD patients aged 5–15 years. Logistic regression analysis confirmed age at initiation of dialysis to be a predictor of patient death (P=0.0001) in the whole patient population, and of technique failure in HD (P=0.006) but not in CPD patients (P=0.16). [ABSTRACT FROM AUTHOR]

In this article, industrial control systems include networked control systems (NCS), which use real-time Ethernet (RTE) protocols since many years, well before the time sensitive networking initiative debut. Today, ethernet-based control systems are used all across Industry 4.0, including in critical applications, allowing for straight integration with information technology layers. Even if it is known that current RTE protocols do not have strong authentication or ciphering options, it is still very challenging to perform undetected cyber-attacks to these protocols while the NSC is in operation, in particular because such attacks must comply with very strict and small temporal constraints. In this article, a model-based attack is proposed for service degradation of NCS. The attack is carried out in real-time and it can remain undetected for the entire plant life. The attack can be applied to any RTE protocols and, without loss of generality, a detailed analysis of stealth techniques is provided for a specific real use case based on PROFINET. The experimental results demonstrate the feasibility of the proposed attack and its high effectiveness. The article also points out some possible future investigation directions in order to mitigate the attack. [ABSTRACT FROM AUTHOR]

Glomerulocystic kidney disease (GCKD) is a rare congenital condition that is usually reported in infants and young children. Only five cases of acquired GCKD after an acquired renal disease have been reported. Among these, two patients have developed cystic glomerular lesions following hemolytic uremic syndrome (HUS). We report a third case in a 2-year-old patient with this association. Common features between these three cases include atypical HUS, development of GCKD after prolonged peritoneal dialysis treatment, severe hypertension, and normal-sized kidneys without development of macroscopic cysts. Pathology findings in our patient include heavy expression of epidermal growth factor receptor in proximal tubules and evidence of obstruction of the glomerular outflow. We speculate that cystic dilatation of the Bowman's capsule may be secondary to ischemic lesions leading to proximal tubular obstruction. [ABSTRACT FROM AUTHOR]

Introduction: HIV infection causes pathological changes in the natural killer (NK) cell compartment that can be only partially restored by antiretroviral therapy (ART). We investigated NK cells phenotype and function in children with perinatally acquired HIV (PHIV) and long‐term viral control (five years) due to effective ART in a multicentre cross‐sectional European study (CARMA, EPIICAL consortium). The impact of age at ART start and viral reservoir was also evaluated. Methods: Peripheral blood mononuclear cells (PBMCs) from 40 PHIV who started ART within two years of life (early treated patients (ET), ≤6 months; late treated patients (LT), > 6 months), with at least five years of HIV‐1 suppression (<40 HIV copies/mL), were collected between November 2017 and August 2018. NK phenotype and function were analysed by flow cytometry and transcriptional profile of PBMCs by RNA‐Seq. HIV‐1 DNA was measured by real‐time polymerase chain reaction (Data were analysed by Spearman correlation plots and multivariable Poisson regression model (adjusted for baseline %CD4 and RNA HIV viral load and for age at ART start as an interaction term, either ET or LT) to explore the association between NK cell parameters and HIV reservoir modulated by age at ART start. Results: A significantly higher frequency of CD56neg NK cells was found in LT compared with ET. We further found in LT a positive correlation of CD56neg NK cells with HIV‐1 DNA. LT also displayed increased expression of the NKG2D and NKp46 activating receptors and perforin compared with ET. Moreover, CD107a+ and IFN‐γ+ frequencies in non‐stimulated NK were associated with HIV‐1 DNA in LT patients. Finally, RNA‐Seq analysis showed in LT an up‐regulation of genes related to NK‐activating pathways and susceptibility to apoptosis compared with ET. Conclusions: We show that early initiation of ART during infancy preserves the NK compartment and is associated with lower HIV‐1 reservoir. Such condition persists over adolescence due to long‐term viral control achieved through effective ART. [ABSTRACT FROM AUTHOR]

[Display omitted] The approach to the built environment as a container of human activities has been severely outdated with a new vision that puts the user, his/her well-being and his/her experience, at the centre, shifting from the old "building as a product" to the newer "building as a service" and the newest "building as an experience" concept. Nevertheless, the sick building syndrome, mainly documented in office buildings, is a widespread problem in many public buildings and, among these, in educational facilities. In these categories we can list school and university buildings where the users are not only workers but also students, sharing anyway the same problem: an artificial environment which is not supporting their productivity in the office or learning performance in the classrooms. Carbon dioxide concentration, due to the natural human breathing process, is a diffuse parameter strongly influencing the indoor air quality and, thus, the users' wellbeing. An acceptance threshold of 1000 ppm in indoor spaces has been derived for this pollutant. Although allowed, the CO 2 concentration in indoor space shouldn't reach this threshold because in such a condition a 11–23% reduction of the users' cognitive performance has been measured and, when the level increases reaching 2500 ppm, the reported drop is dramatic (44–94%). Extensive researches set the optimal threshold at 600 ppm, a level defined as fresh air. Then, how is it possible to encompass a natural process as CO 2 production by humans? Basically with the correct ventilation rate, depending on room geometry, number of people and ventilation system (i.e. natural or mechanical or mixed). A modulating mechanical ventilation system could adapt the ventilation rate according to people density and changing indoor conditions nevertheless many existing buildings have outdated systems not providing this option. Sometimes their air handling units (AHUs) have few regulation options to control the parameters and tuning procedures during the building lifecycle are required. CO 2 concentration is convenient to measure indoor air quality because it is easily quantifiable through a sensors network. Thus, it may be adopted as an indicator to assess suitable indoor conditions to human activities and used to trigger manual or automatic procedures to preserve wellbeing thresholds. The article presents a research work depicting the integration of indoor air quality data gathered by internet of things (IoT) sensors to activate the control of the indoor conditions according to the occupancy rate in the educational building eLUX lab, located in the Smart Campus of the University of Brescia. The challenge is to directly regulate the heating, ventilation and air conditioning (HVAC) systems and define opening/closing patterns for windows to improve the indoor air quality and protect the learning performance of users in dynamic use conditions. The embraced methodology suggests the training of an artificial neural network (ANN) with the actual monitored data and to trigger the ventilation rate control through an IoT communication protocol. [ABSTRACT FROM AUTHOR]

Background Assays to estimate human immunodeficiency virus (HIV) reservoir size require large amounts of blood, which represents a drawback especially in pediatric settings. We investigated whether HIV-antibody repertoire could estimate the viral reservoir size. Moreover, we assessed the magnitude of HIV-antibody response as a predictor of time of antiretroviral therapy (ART) initiation. Methods Human immunodeficiency virus-antibody responses to 10 different viral proteins were evaluated by HIV Western blot (WB) kit and a WB score was assigned to each patient. Patients were classified in 2 subgroups based on the timing of ART initiation (early treated [ET], 0–24 weeks and late treated [LT], >24 weeks). Human immunodeficiency virus-deoxyribonucleic acid (DNA) was quantified using real-time quantitative polymerase chain reaction on total peripheral blood mononuclear cells. Logistic regression and principal component analysis were built on these data to test the ability of WB score to predict the expected value of HIV-DNA and the timing of ART initiation. Results Sixty-nine perinatally HIV-infected children were evaluated. Reduced HIV-specific antibody responses and lower size of HIV-DNA were observed in ET compared with LT patients (P <.001 and P =.02, respectively). We found that WB score correlates with HIV-DNA (P =.032) and timing of ART initiation (P <.001). Based on the logistic regression analysis, we found that WB score can predict the HIV-DNA size and the timing of ART initiation with an Akaike information criterion of −118.13 and −151.51, respectively. Conclusions Western blot score can estimate HIV-DNA size and timing of ART initiation in long-term virally suppressed children. This rapid, inexpensive, and easily reproducible tool can provide useful information to identify potential candidates for HIV remission studies. [ABSTRACT FROM AUTHOR]

The availability of low-power wide area networks solutions opens new scenario in many application sectors. Among these technologies, long-range wide area network (LoRaWAN) was originally designed for consumer internet-of-things systems, but now it is investigated for distributed measurement systems applied to more demanding applications, including industry. In order to fulfill real-time requirements, the LoRaWAN end devices (EDs) are frequently requested to share a common timebase (i.e., to be synchronized). This paper deals with the tradeoff between the desired synchronization uncertainty and the energy available in the ED, which is usually battery powered. A new approach based on two algorithms for a posteriori synchronization and uncertainty estimation is proposed. After experimental validation of the proposed algorithms, a set of optimal energy/uncertainty tradeoff curves is obtained with the help of a specific tradeoff algorithm. Finally, the proposed tradeoff methodology is applied to two use cases concerning the design of: an industrial time division multiple access system and a predictive maintenance framework. [ABSTRACT FROM AUTHOR]

This paper investigates the ultimate limits of White Rabbit (WR), an high-accuracy time distribution system based on field-programmable gate array (FPGA). The knowledge of such limits is essential for new emerging applications that are evaluating WR. In this paper, we identify and study the key elements in the WR synchronization: the digital dual mixer time difference phase detector and the Gigabit Ethernet transceiver. The benchmarks and experimental analysis of these key elements allow us to determine the WR switch (WRS) performance limits and evaluate their evolution with newer FPGAs. The identified performance limits are achievable by the present-day generation of WRS. The ultimate limits of short-term synchronization performance due to FPGA implementation have been derived through analysis and then demonstrated using the existing WRS enhanced with an additional daughterboard. This combination (WRS and daughterboard) achieves a tenfold improvement in terms of phase noise, jitter, and short-term stability with respect to the current WR performance. Both phase detectors and Gigabit transceivers have a similar phase noise contribution equal to a short-term stability of modified Allan deviation 4E−13 at $\tau = 1$ s (dominated by flicker phase modulation noise). [ABSTRACT FROM AUTHOR]

Information and operational technologies merge into the so-called industrial Internet of Things, which is one of the basic pillars of the Industry 4.0 paradigm. Roughly speaking, yet-to-come services will be offered in the automation scenario by industrial devices having an internet connection for sharing data in the cloud. Currently, most efforts are in the development of protocols able to ensure horizontal interoperability among heterogeneous applications. Consequently, poor attention is devoted to time-related performance. In this paper, a new, full software, platform-independent approach is proposed for experimentally evaluating the delay in transferring information across local and intercontinental routes by applications leveraging on messaging middleware. The application is realized using the node-RED web-based framework, due to its availability on different platforms; the widely accepted message queue telemetry transport protocol has been chosen thanks to its low overhead and complexity. For sake of completeness, five different, private and public, brokers are used. The adopted industrial-grade hardware, complemented by global positioning system time reference, permits an overall synchronization and timestamping accuracy of a few milliseconds. The vast measurement campaign highlighted that, generally, quality of service (QoS) type 1 offers low end-to-end delay (average value less than 0.5 s) with reduced variability (0.1 s). However, the maximum end-to-end one-way delay ranges from 1 s for QoS 0 to less than 1.5 s for fully acknowledged QoS 2. [ABSTRACT FROM AUTHOR]

HIV-infected patients of all ages frequently underperform in response to seasonal influenza vaccination, despite virologic control of HIV. The molecular mechanisms governing this impairment, as well as predictive biomarkers for responsiveness, remain unknown. This study was performed in samples obtained prevaccination (T0) from HIV-infected children who received the 2012-2013 seasonal influenza vaccine. Response status was determined based on established criterion for hemagglutination inhibition titer; participants with a hemagglutination titer ≥1:40 plus a ≥4-fold increase over T0 at 3 wk postvaccination were designated as responders. All children had a history of prior influenza vaccinations. At T0, the frequencies of CD4 T cell subsets, including peripheral T follicular helper (pTfh) cells, which provide help to B cells for developing into Ab-secreting cells, were similar between responders and nonresponders. However, in response to in vitro stimulation with influenza A/California/7/2009 (H1N1) Ag, differential gene expression related to pTfh cell function was observed by Fluidigm high-density RT-PCR between responders and nonresponders. In responders, H1N1 stimulation at T0 also resulted in CXCR5 induction (mRNA and protein) in CD4 T cells and IL21 gene induction in pTfh cells that were strongly associated with H1N1-specific B cell responses postvaccination. In contrast, CD4 T cells of nonresponders exhibited increased expression of IL2 and STAT5 genes, which are known to antagonize peripheral Tfh cell function. These results suggest that the quality of pTfh cells at the time of immunization is important for influenza vaccine responses and provide a rationale for targeted, ex vivo Ag-driven molecular profiling of purified immune cells to detect predictive biomarkers of the vaccine response. [ABSTRACT FROM AUTHOR]

Background: In the field of kidney transplantation, identifying early signatures of humoral rejection is a key challenge. Methods: We investigated the presence of anti-HLA antibodies and the distribution of lymphocyte subpopulations in 77 kidney-transplanted children and young adults compared to 23 healthy controls. Moreover, we tested whether the presence of anti-HLA antibodies could be related to modification in lymphocyte phenotype. Finally, we correlated the presence of anti-HLA antibodies and specific alteration of lymphocyte subsets with clinical outcomes. Results: In kidney-transplanted children who developed anti-HLA antibodies, we observed an expansion of double-negative B cells (CD19 + CD27-IgD-), indicating premature aging of this compartment. Moreover, we reported signs of impaired B cell regulation, indicated by a higher IL-21R+ B cell frequency associated with an abnormal increase of follicular helper T cells. Finally, a considerable reduction in CD8+ effector T and invariant Natural killer T (NKT) cells was observed. The stability of graft function over time is significantly correlated with the frequency of peripheral effector CD4+ and CD8+ T cells and invariant NKT cells. Conclusions: This study supports the usefulness of lymphocyte subset as one of a spectrum of early diagnostic tools required to identify patients at risk of developing donor alloimmune response. [ABSTRACT FROM AUTHOR]

The knowledge of the time value at which an event of interest occurred is the typical feature needed to perform many kinds of postprocessing in distributed sensor networks. Consequently, network-based distributed systems must support time dissemination in order to ensure that relative clock errors among nodes remain below a certain threshold. Despite many protocols being well established for wired connections, the wireless sensor network paradigm required a new approach to address adverse characteristics of the wireless medium. In this paper, the adoption of low-frequency signaling is proposed for overcoming some issues of radio frequency transmissions when used for timestamping events. The proposed approach is characterized using numerical simulations and an experimental prototype, based on inductive coupling of tuned resonators. Experimental tests confirm the effectiveness and feasibility of this approach that achieves microsecond-order time recovery performance in practical system configurations. [ABSTRACT FROM PUBLISHER]

Protection and measurement systems in electrical substations are required to have high availability. In an all-digital substation protection system, all the components (instrument transformers, processing units, merging units, intelligent electronic devices, communication network, and synchronization source) may affect the overall availability level. In this paper, a solution to enhance distributed PMU availability, during wired network failures, is presented. In the proposed scheme, the process bus has two parallel networks: 1) the classic wired Ethernet link and 2) a wireless link (implemented with industrial grade IEEE 802.11 devices), for sampled values packets, which carry measurement information. The time synchronization is carried out only through the wired Ethernet link, but the proposed solution is still able to compensate temporary failures of one of the communication links. Experimental tests have been performed to verify the performance of additional IEEE 802.11 link using different protocols and configurations. Communication parameters that can affect the PMU performance, like propagation latency, are characterized. It is shown that, if the measurement algorithm is opportunely designed, depending on the wireless link quality, it is possible to comply, with a single output, with M and P classes of the synchrophasor standard also during network restoration or, at least, to safeguard protection applications if higher latency occurs. [ABSTRACT FROM PUBLISHER]

Network time distribution relies on timestamping, which is employed by local nodes to assign a time value to incoming timing packets. Clearly, any error affecting the timestamp has a direct impact on the final synchronization accuracy of the system. In wireless sensor networks (WSNs), impairments affecting the wireless physical layer are the primary cause of such timestamping errors, and it would be advantageous to flag suspect timestamp values before feeding them into a synchronization algorithm. This paper discusses a new strategy for validating timestamps in a WSN based on IEEE 802.15.4 chirp spread spectrum. The considered system employs physical-level timestamping, which generates one timestamp for each symbol belonging to a packet. Such set of timestamps is processed using a Kalman filter (KF) that compares them with predicted values, employing statistical thresholds referred to the KF innovation process. Experimental results obtained over a long observation period shows that even in a noisy environment with several interfering communication sources, the algorithm is able to detect untrusted timestamps. [ABSTRACT FROM PUBLISHER]

This paper proposes a new distributed architecture to measure synchrophasors in power substations, inspired by the standards IEC 61850. The new scheme is implemented in the process bus, where a high performance merging unit (MU), synchronized by precision time protocol (PTP), according to the standard IEEE 1588–2008, sends the sampled values (SVs) to an intelligent electronic device (IED) enabled to behave as a phasor measurement unit (PMU). The synchrophasors are evaluated in the IED through an algorithm based on the Taylor Fourier Transform and suitably modified to have high performance also in terms of response time in presence of step change conditions. Different tests and considerations are presented to evaluate the various elements of uncertainty that a distributed architecture can introduce and, finally, to ensure the feasibility of the proposed approach. [ABSTRACT FROM PUBLISHER]

The IEC 61850 standard allows for a structured grid automation system where critical tasks like grid protections, renewable energy sources management, synchronized measurements, and monitoring applications share the communication network. So far, the use of IEC 61850 has been mainly limited to the primary substations, but more interesting could be the coordinated actions between primary and secondary substations in order to quickly react to faults and to reduce service downtimes for final customers. Unfortunately, the communication networks between primary and secondary substations are today only partially deployed. Considering this context, the broadband power line over medium voltage grid (MV-BPL) could be a suitable solution for closing the communication gaps between substations that use IEC 61850. The main objective of this paper is to present the outcomes of the first phase of a project whose final goal is the implementation in real grids of distribution grid automation based on IEC 61850. A new and comprehensive set of experiments on a real (and in service) medium voltage grid in Italy has been designed and carried out. The practicability of IEC 61850 communication over the distribution grid is assessed comparing the time characteristics of the MV-BPL against the transfer time classes of the IEC 61850, determining which IEC 61850 services may be transported over MV-BPL. The experimental long-term analysis highlights that more than 90% of the service requests are transferred on the network with a round-trip time lower than 40 ms even in the case of four hops, a time which is compatible with the IEC 61850 fast automatic interactions on MV grid. [ABSTRACT FROM AUTHOR]

Wireless sensor networks are becoming widely diffused because of the flexibility and scalability they offer. However, distributed measurements are significant only if the readout is coupled to time information. For this reason, network-wide time synchronization is the main concern. The objective of this paper is to exploit a very simple hardware implementation of an IR-UWB radio for realizing an accurate synchronization system for wireless sensors. The proposed solution relies on commercial-off-the-shelf discrete electronic components (rather than on specialized transceivers). It is designed for providing accurate timestamping of the packet time of arrival (TOA) to an adder-based tunable clock, which tracks the network time reference. The comprehensive set of experimental results based on prototypes, shows a TOA detection error with a standard deviation well below 1 ns. On the other hand, in the FPGA-based prototype, the synchronization performance reaches an overall synchronization error of few nanoseconds. Finally, in order to highlight the tradeoff between timestamping accuracy, clock stability, and synchronization performance, some additional simulations have been carried out: a synchronization error in the order of 1 ns is possible, if good local oscillator sources are available in the nodes and if the adjustable clock has a sufficient resolution. [ABSTRACT FROM AUTHOR]