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This article investigates the effects of operating current, soil properties, and UV ageing on the insulation resistance of cables used in the photovoltaic (PV) industry. Based on standardized experimental tests, the temperature-dependent conductivity was measured, and therefore the temperature–conductivity relationship for each cable type is extracted. Using the Arrhenius equation, a mathematical model was developed, which provided the basis for subsequent simulations of the cable insulation resistance based on the thermal properties of the insulation material, surrounding soil, and the current flowing through the conductor. The simulation provided insights into the dynamic changes of the insulation resistance based on the operating parameters. Moreover, the experimental UV ageing of cables used in the PV industry provided important insights regarding the downgrading of the insulation resistance upon prolonged exposure to the sun. [ABSTRACT FROM AUTHOR]

• In response to the reviewer's valid concerns, we have introduced a clear and comprehensive note in the paper, elucidating our deliberate departure from the conventional theoretical approach traditionally embraced by the industry, which predominantly centres around the lightning current sharing rule (50:50). • This advanced modelling approach stands out for its capability to meticulously scrutinise a multitude of parameters and explore diverse what-if scenarios. By doing so, we not only elevate the precision and depth of our analysis but also broaden the scope of our investigation to encompass a more comprehensive range of potential factors and conditions. • The focus of our paper is primarily on emphasising the approach to mitigate the risk of voltage stress across insulation flanges, particularly examining the influence of connecting lead lengths. It's crucial to interpret the absolute values in the results with care, as they are indicative of an extreme scenario involving high impulse current (200 kA) and steepness (20 kA/μs). While these values represent an extreme case, the main takeaway from our calculations remains valid. There is a quantifiable reduction in the range of 34 % when implementing the proposed mitigation measures, signifying a substantial contribution to risk mitigation. • We have incorporated a dedicated section into the paper, labelled as 4.1 sensitivity analysis. Insulating flanges serve as crucial components, strategically positioned between two segments of a pipeline to ensure effective electrical isolation. These elements play a vital role in facilitating the optimal performance of the cathodic protection system of buried pipeline networks. Moreover, an isolating spark gap is commonly integrated between adjacent pipeline sections to mitigate the stress voltage induced on the insulating flange during lightning strike events.. Despite this protective measure, certain scenarios may arise where the voltage drop across the isolating spark gap's connecting cables surpasses the insulating flange's dielectric strength, leading to undesirable failures. The magnitude of this voltage drop is contingent upon various factors, including the parameters of the incoming surge as well as the length of the connecting cables. In this paper, we present both straightforward theoretical calculations and intricate modelling techniques that can be employed to assess the lightning risk associated with the insulating flanges of pipelines that incorporate isolating spark gaps. [ABSTRACT FROM AUTHOR]

This work falls under the preliminary engineering studies that are carried out to assess the interference impact, which may be raised from the operation of the bipolar HVdc cable link between Attica and Crete. The interference impact concerns critical and public infrastructures that are located in close proximity to the intended link's on-shore routing. In this article, particular emphasis is given in modeling a specific interference situation, on a collocated railway system, that ascends from pole-to-ground fault conditions that may occur on the planned bipolar voltage source converter (VSC)-HVdc cable network. To this extent, the simulation analysis takes into account the specific characteristics of the interfering VSC-HVdc technology and the results are constructively benchmarked against the safety thresholds tabulated in international standards. [ABSTRACT FROM AUTHOR]

Wall fusion of buried pipelines can occur if the driving voltage and available current is sufficiently high. For example, it can occur from direct lightning strikes to earth, close to the pipelines’ routing. However, not all factors for defining the energy discharge needed to fuse the pipe wall are thoroughly investigated or understood. This paper enriches the ongoing research activities in an attempt to understand such detrimental damages. In particular, the paper formulates its research contents around a documented wall fusion incident on an underground gas transmission system, due to a nearby direct lightning strike. The investigation embraces field, laboratory, and modeling activities to provide insights on the damaging mechanism. Of particular importance in understanding this mechanism is the influence of soil ionization. To this end, a model is developed to investigate the soil-ionized flow of the lightning discharge current—into the pipeline's metal wall, through existing coating defects—thus revealing its detrimental effect. [ABSTRACT FROM AUTHOR]

Short-term electromagnetic interference (EMI) pertains to the total result produced by the occurrence of intermittent, inductive, and conductive couplings on a buried pipeline system. For example, this type of EMI takes place when considering the fault conditions of a single ac power line, acting in the nearby vicinity of a pipeline system. In the context of this article, the effect of the short-term EMI is unfolded through a real case study. This case study involves a 20.7-MW wind park (WP) with extended underground power cable connections, which are laid nearby a high-pressure gas pipeline system. In particular, the impact of critical fault events, associated with the WP's power cables, on the pipeline system is comprehensively assessed. The assessment is achieved by the concurrent use of two powerful software tools that are respectively eligible for the accurate short-circuit analysis of the electrical circuit of the WP and for EMI evaluation on the pipeline. To this extent, the simulation results are thoroughly discussed and an effective mitigation solution is evidently presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two genetically distinct epigean Schizidium clades with well-defined geographic boundaries were identified from Cyprus. • The importance of the paleogeography on evolutionary processes within the island is highlighted. • A new cryptic, epigean Schizidium species occurring on Cyprus and Turkey is described based on genetic evidence. • A new endogean endemic to Cyprus Schizidium species is described utilizing genetic and morphological data. • Additional evidence of genetic divergence that is not paralleled by morphological differentiation in Oniscidea is provided. • The proposed phylogeographic relation of Cyprus fauna with neighboring eastern Mediterranean regions is enhanced. Cyprus is a Mediterranean island of volcanic origin isolated for at least 5.3 Myr from surrounding continental areas. The present study focuses on the diversification of the isopod genus Schizidium within the island, including also specimens from surrounding continental areas. The genus Schizidium sensu lato is probably non monophyletic, comprising 26 species distributed from Greece to Iran. Up to date the only representative of the genus reported from Cyprus was Schizidium fissum. Aiming to investigate the patterns of genetic diversity within the focal island, to evaluate the morphology-based taxonomy of the species in the genus, and at the same time to explore phylogenetic relationships with mainland populations, we applied genome-wide ddRADseq as well as Sanger sequencing targeting three mitochondrial (16S, COI and 12S) and the nuclear NaK loci. Results of phylogenetic analyses support the existence of two distinct epigean Schizidium clades with well-defined geographic boundaries that conform to the known paleogeography of Cyprus, plus one endogean clade with restricted distribution within the island. Genetic data and morphology corroborate the assignment of this latter endogean clade to a new species, Schizidium myrrae n. sp. The two epigean clades are also considered as distinct species, one corresponding to the known S. fissum at the eastern part of the island (Pentadaktylos massif) and the other to the newly described S. christosi n. sp. distributed along the western part of the island (Troodos massif). Even though detailed examination of many specimens could not retrieve any morphological differences among representatives of these two clades, clado-chronological analysis indicates a long isolation between them, estimated at ∼ 9 Mya, as well as the sharing of a common ancestor with S. tiberianum from Israel at ∼ 15 Mya. Hence, we can consider these epigean Schizidium species as one more case of cryptic diversity on Cyprus, exhibiting similar patterns with the recently described case in the genus Armadillo. [ABSTRACT FROM AUTHOR]

In grounded photovoltaic (PV) systems, dc leakage to earth is formed by the contribution of the PV modules, inverters, and dc circuitry. Ground faults in such systems occur when there is an unintentional connection between any dc-carrying conductor with a grounded surface or earth. On the occurrence of ground faults, dc leakage will be intensified and will flow through the earth or other conductive paths, before returning back to the source. Thus, it is highly probable that some portion of the dc leakage will attempt to return to the source through any low-resistance paths that exist in the nearby vicinity, for example, through nearby buried pipelines. Therefore, unattended dc leakage may induce stray current corrosion concerns on these pipelines. To this extent, this paper presents a detailed dc interference modeling for assessing the dc leakage activity in PV systems—particularly under undetected fault conditions. First, the modeling carried out embraces the topologically accurate consideration of all sources of dc leakage that are associated with the grounded PV systems. A second feature presented in the paper is the modeling of blind-spot dc faults and their impact on third-party infrastructure. [ABSTRACT FROM AUTHOR]

Porcellionidae is one of the richest families of Oniscidea, globally distributed, but we still lack a comprehensive and robust phylogeny of the taxa that are assigned to it. Employing five genetic markers (two mitochondrial and three nuclear) we inferred phylogenetic relationships among the majority of Porcellionidae genera. Phylogenetic analyses conducted via Maximum Likelihood and Bayesian Inference resulted in similar tree topologies. The mtDNA genes cytochrome oxidase I (COI) and 16s rRNA (16s) were used for clade dating using previously published mutation rates. Our results provide evidence against the monophyly of both Porcellionidae and the largest genus of the family, Porcellio. These results are compared to previous published work based on morphological evidence. The genera Leptotrichus and Brevurus are not grouped with the rest of Porcellionidae whereas Agnaridae are grouped with part of Porcellionidae. Armadillidium and Schizidium (Armadillidiidae) occupy a basal position on the phylogenetic tree. Even though the African genera Tura and Uramba (distributed in East Africa) are grouped together, there is no general geographical pattern in other sub-clades. Additional taxonomic issues that arise in this work, such as the assignment of the recently described genus Levantoniscus, are also discussed. The status of Porcellionidae should be further revised and morphological characters traditionally used in Oniscidea taxonomy should be reconsidered in view of molecular evidence. The origin of the monophyletic clade within Porcellionidae, as indicated in the present work, is dated back to the Oligocene (~32 mya). [ABSTRACT FROM AUTHOR]

[Display omitted] • Six genetically discrete A. officinalis groups across the study area were identified, four of which endemic to the island of Cyprus. • MSC facilitated the arrival of the species on the island. • Species delimitation supports the existence of at least three species, two of which new for science, one endemic to Cyprus, one in Israel, and one corresponding to the nominal species. • Cryptic diversity has been revealed, not reflected in morphology. • Geological history coupled with recent human activities have shaped observed diversity patterns. Understanding intra-island patterns of evolutionary divergence, including cases of cryptic diversity, is a crucial step towards deciphering speciation processes. Cyprus is an oceanic island isolated for at least 5.3 Mya from surrounding continental regions, while it remains unclear whether it was ever connected to the mainland, even during the Messinian Salinity Crisis. The terrestrial isopod species Armadillo officinalis , that is widespread across the Mediterranean, offers the opportunity to explore intra-island divergence patterns that might exhibit geographical structure related also to the region's known paleogeography. Genome-wide ddRADseq, as well as Sanger sequencing for four mitochondrial and three nuclear loci data were generated for this purpose. In total, 71 populations from Cyprus, neighbouring continental sites, i.e., Israel, Lebanon and Turkey, and other Mediterranean regions, i.e. Greece, Italy, and Tunisia, were included in the analysis. Phylogenetic reconstructions and population structure analyses support the existence of at least six genetically discrete groups across the study area. Five of these distinct genetic clades occur on Cyprus, four of which are endemic to the island and one is widely distributed along the circum-Mediterranean countries. The sixth clade is distributed in Israel. The closest evolutionary relationship of endemic Cypriot populations is with those from Israel, while the evolutionary clade that is present in countries all around the Mediterranean is very shallow. Cladochronological analyses date the origin of the species on the island at ∼6 Mya. Estimated f4 and D statistics as well as F ST values indicate the genetic isolation between the populations sampled from Cyprus and surrounding continental areas, while there is evident gene flow among populations within the island. Species delimitation and population genetic metrics support the existence of three distinct taxonomic units across the study area, two of which occur on the island and correspond to the endemic clade and the widespread circum-Mediterranean one, respectively, while the third corresponds to Israel's clade. The islands' paleogeographic history and recent human activities seem to have shaped current patterns of genetic diversity in this group of species. [ABSTRACT FROM AUTHOR]

Widespread reports over the last six years confirm the establishment of lionfish (Pterois miles) populations in the eastern Mediterranean. Accumulated knowledge on lionfish invasions in the western Atlantic Ocean has shown that it is a successful invader and can have negative impacts on native species, indirect ecological repercussions and economic effects on local human societies. Here we analysed genetic sequences of lionfish from Cyprus as well as data from the whole distribution of the species, targeting the mtDNA markers cytochrome c oxidase subunit 1 (COI) and the control region (CR). Our results reflect a pattern of repeated introductions into the Mediterranean from the northern Red Sea and a secondary spread of this species west to Rhodes and Sicily. Presented results agree with previously published studies highlighting the genetic similarity with individuals from the northern Red Sea. Nevertheless, some individuals from Cyprus, in addition to those coming via the Suez Canal, were genetically similar to fish from the Indian Ocean, indicating genetic homogeneity among populations of P. miles across its current distribution, possibly facilitated by the ornamental fish trade and/or transport through ballast water. [ABSTRACT FROM AUTHOR]

The dragonfly genusIschnurahas been the subject of numerous studies and is well studied in Europe and the Middle East. Nevertheless, information on the ecology, habitat preferences and phylogenetic relationships of some species is deficient. One species lacking such data isIschnura intermedia, a near endemic species of the Middle East, found for the first time in Europe on Cyprus in 2013, where it occurs in five river valleys. In this study, we monitoredI. intermediain Cyprus where the species has a long flight period from the end of March until mid-November. Our results show that it has two and possibly even three generations a year, with the males of the first generation having reduced blue coloration on abdominal segments 8 and 9. Ischnura intermediais confined to small secondary channels adjacent to streams and rivulets where the current slows and water is retained. It appears that populations can only become established at sites that have permanent water. It is therefore anticipated that the species will be under severe pressure within its range. We suggest listing this species as “Endangered” in Europe and globally as “Vulnerable” following the IUCN Red List Categories and Criteria and to prepare a species action plan for the European population ofIschnura intermediaon Cyprus. Two partial DNA fragments, mtDNA cytochrome b (Cytb) and cytochrome oxidase subunit I (COI) were used to gain insights into the phylogenetic position withinIschnura, especially within theI. pumilioclade. We demonstrate thatI. intermediais clearly separated fromI. pumilio, but closely related toI. forcipata. [ABSTRACT FROM PUBLISHER]

Propomacrus cypriacusa saproxylic beetle endemic to Cyprus, was described as a species distinct fromP. bimucronatuson the basis of a few morphological characters and has been evaluated as Critically Endangered by IUCN, as it depends on veteran trees and has a restricted distribution. Herein we explored the distribution, ecology, morphology and genetic variation of the populations from Cyprus, and we attempted a phylogenetic analysis including related species based on two mitochondrial and one nuclear DNA markers. We also used published mtDNA divergence rates to date cladogenetic events. Despite extensive sampling, we found only a small number of individuals, adding a few additional localities to the known distribution of the species, and we identified two more host species to those previously reported. Morphological examination showed that only the form of male protibiae differs consistently in Cyprus populations compared to those ofP. bimucronatusfrom Turkey and the Lebanon. Nevertheless, genetic analyses do not support a distinct species status for populations from Cyprus, which should instead be considered as a subspecies ofP. bimucronatus. Morphological and ecological data further support this conclusion. Cyprus populations have diverged from nearby continental ones in mid to late Pleistocene. [ABSTRACT FROM AUTHOR]