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The behavior of a photovoltaic (PV) generator under specific irradiance and temperature conditions is mainly described by its current–voltage (I-V) characteristic. Therefore, the I-V curve tracing has to be considered the most accurate and effective diagnostic tool for the proper identification of PV panels’ failures. In this article, an innovative I-V curve tracer for individual PV panels is presented. It ensures the following advantages. 1) An optimized I-V curve measurement due to an innovative tracing algorithm. 2) In-situ characterization during normal operation owing to a proper disconnection circuit. 3) Full portability thanks to a Li-ion battery power supply and a Bluetooth communication. The proposed tool has been designed and realized. The resulting prototype has been used to measure the I-V curve of a PV panel both in uniform and partial shading conditions.

This study presents a comprehensive evaluation of an in-house developed current-voltage (I–V) curve tracer compared to the widely used Seaward PV200. Our device, a wireless, microcontroller-based tracer, is designed for precise monitoring of photovoltaic (PV) panels, significantly outperforming the PV200 in speed and measurement quality. Key features include an innovative disconnecting circuit that allows integration into PV strings without disrupting energy production and a control algorithm that evenly distributes measurement points along the I–V curve. Experimental results, obtained under nonuniform irradiation, demonstrate our tracer’s capability to accurately detect operational conditions, such as the activation of bypass diodes. Electroluminescence testing further validated the integrity and performance of the examined panels, emphasizing the importance of advanced instrumentation in enhancing solar energy system efficiency. Our findings highlight substantial advancements in PV diagnosis, offering a robust tool for performance analysis and fostering the development of efficient solar energy solutions.

Epigenetics is a field of biological sciences focused on the study of reversible, heritable changes in gene function, not due to modifications of the genomic sequence. These changes are the result of a complex cross-talk between several molecular mechanisms that is in turn orchestrated by genetic and environmental factors. The epigenetic profile captures the unique regulatory landscape and the exposure to environmental stimuli of an individual. It thus constitutes a valuable reservoir of information for personalized medicine, which is aimed at customizing health-care interventions based on the unique characteristics of each individual. Nowadays, the complex milieu of epigenomic marks can be studied at the genome-wide level thanks to massive, high-throughput technologies. This new experimental approach is opening up new and interesting knowledge perspectives. However, the analysis of these complex omic data requires to face important analytic issues. Artificial Intelligence, and in particular Machine Learning, are emerging as powerful resources to decipher epigenomic data. In this review, we will first describe the most used ML approaches in epigenomics. We then will recapitulate some of the recent applications of ML to epigenomic analysis. Finally, we will provide some examples of how the ML approach to epigenetic data can be useful for personalized medicine.

We evaluated efficacy of natalizumab in relapsing-remitting multiple sclerosis patients in a clinical practice setting. We report data on the first consecutive 343 patients receiving natalizumab in 12 multiple sclerosis (MS) Italian centers enrolled between April 2007 and November 2010. The main efficacy endpoints were the proportion of patients free from relapses, disease progression, combined clinical activity, defined as presence of relapse or disease progression, from MRI activity, and from any disease activity defined as the absence of any single or combined activity. At the end of follow-up, the cumulative proportion of patients free from relapses was 68%; the proportion of patients free from Expanded Disability Status Scale (EDSS) progression was 93%; the proportion of patients free from combined clinical activity was 65%; the proportion of patients free from MRI activity was 77%; and the proportion of patients free from any disease activity was 53%. Natalizumab was effective in reducing clinical and neuroradiological disease activity. Its effectiveness in clinical practice is higher than that reported in pivotal trials and was maintained over time.

This paper deals with operating speed and hazardousness on two-lane roads and will define the characteristics (components) of driving environments (scenarios) used in an analysis procedure developed by authors in a Decision Support System (DSS). DSS aims to identify infrastructure projects, given a total cost, suitable to produce maximum reduction of social cost of crashes. Results obtained are the improvement of the V85formula and the trend of the Crash Index as a function of flow/capacity ratio in limited access two-lane roads. Both results show that limited access roads and at grade intersections roads must be handled as different scenarios.

PSII catalyzes the oxidation of water and reduction of plastoquinone in oxygenic photosynthesis. PSII contains an oxygen-evolving complex, which is located on the lumenal side of the PSII reaction center and which contains manganese, calcium, and chloride. Four sequential photooxidation reactions are required to generate oxygen. This process produces five Sn-states, where nrefers to the number of oxidizing equivalents stored. Calcium is required for oxygen production. Strontium is the only divalent cation that replaces calcium and maintains activity. In our previous FT-IR work, we assessed the effect of strontium substitution on substrate-limited PSII preparations, which were inhibited at the S3to S0transition. In this work, we report reaction-induced FT-IR studies of hydrated PSII preparations, which undergo the full S-state cycle. The observed difference FT-IR spectra reflect long-lived photoinduced conformational changes in the oxygen-evolving complex; strontium exchange identifies vibrational bands sensitive to substitutions at the calcium site. During the S1′ to S2′ transition, the data are consistent with an electrostatic or structural perturbation of the calcium site. During the S3′ to S0′ and S0′ to S1′ transitions, the data are consistent with a perturbation of a hydrogen bonding network, which contains calcium, water, and peptide carbonyl groups. To explain our data, persistent shifts in divalent cation coordination must occur when strontium is substituted for calcium. A modified S-state model is proposed to explain these results and results in the literature.

In oxygenic photosynthesis, PSII carries out the oxidation of water and reduction of plastoquinone. The product of water oxidation is molecular oxygen. The water splitting complex is located on the lumenal side of the PSII reaction center and contains manganese, calcium, and chloride. Four sequential photooxidation reactions are required to generate oxygen from water; the five sequentially oxidized forms of the water splitting complex are known as the Sn states, where n refers to the number of oxidizing equivalents stored. Calcium plays a role in water oxidation; removal of calcium is associated with an inhibition of the S state cycle. Although calcium can be replaced by other cations in vitro, only strontium maintains activity, and the steady-state rate of oxygen evolution is decreased in strontium-reconstituted PSII. In this article, we study the role of calcium in PSII that is limited in water content. We report that strontium substitution or 18OH2 exchange causes conformational changes in the calcium ligation shell. The conformational change is detected because of a perturbation to calcium ligation during the S1 to S2 and S2 to S3 transition under water-limited conditions.

An intracellular mechanism activated by nicotinic acid adenine dinucleotide phosphate (NAADP+) contributes to intracellular Ca2+release alongside inositol 1,4,5-trisphosphate (Ins-P3) and ryanodine receptors. The NAADP+-sensitive mechanism has been shown to be operative in sea urchin eggs, ascidian eggs, and pancreatic acinar cells. Furthermore, most mammalian cell types can synthesize NAADP+, with nicotinic acid and NADP+as precursors. In this contribution, NAADP+-induced Ca2+release has been investigated in starfish oocytes. Uncaging of injected NAADP+induced Ca2+mobilization in both immature oocytes and in oocytes matured by the hormone 1-methyladenine (1-MA). The role of extracellular Ca2+in NAADP+-induced Ca2+mobilization, which was minor in immature oocytes, was instead essential in mature oocytes. Thus, the NAADP+-sensitive Ca2+pool, which is known to be distinct from those sensitive to inositol 1,4,5-trisphosphate or cyclic ADPribose, apparently migrated closer to (or became part of) the plasma membrane during the maturation process. Inhibition of both Ins-P3and ryanodine receptors, but not of either alone, substantially inhibited NAADP+-induced Ca2+mobilization in both immature and mature oocytes. The data also suggest that NAADP+-induced Ca2+mobilization acted as a trigger for Ca2+release via Ins-P3and ryanodine receptors.

Cortical granules (secretory vesicles located under the cortex of mature oocytes) release their contents to the medium at fertilization. Their exocytosis modifies the extracellular environment, blocking the penetration of additional sperm. The granules translocate to the surface during the maturation process, and it has been suggested that they move to the cortex via cytoskeletal elements. In this paper we show that the increase in intracellular Ca2+, which the maturing hormone 1-methyladenine (1-MA) induces in starfish through the activation of inositol 1,4,5-trisphosphate (InsP3) receptors, triggers changes in filamentous actin, which then direct the correct movement and reorientation of the cortical granules and the elevation of the fertilization envelope.

Organelles and neurons of nematodes involved in sensing chemical signals present in the environment are described. Laser ablation of neurons has helped assign them a specific function. Genetic mutational analysis has led to the identification of genes controlling the behaviour of the worms and/or some cellular properties of the chemosensory neurons. Some conclusions on the general organization and functioning of chemoreception in nematodes can be drawn.