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High-temperature superconducting tapes can be stacked together to form cables which are then wound into coils for potential use in electrical machines. The tapes in the cable can either be uncoupled (insulated from each other), coupled at ends (coupled at the terminals of the cable), or fully coupled (electrically connected with each other along the whole length of the cable). The integral method can readily model the uncoupled scenario, and this article extends the integral method to model the coupled-at-ends and fully coupled scenarios. We find that the proposed method has a time advantage over the well-established T–A formulation of Maxwell's equations.

Background recently much studies evidenced the potential role of photo-biomodulation (PBM) in patients affected by Age-related Macular Degeneration (AMD). We designed a new wearable device for self-medication that employs the same broadband red light described in literature, but with extremely low irradiance.Aim to demonstrate the safety and effectiveness of low-fluence light stimulations emitted by a LED source with appropriate wavelengths through our new device in improving short-term visual function in patients affected by severe non neovascular AMD.Materials and methods we prospectively enrolled patients affected by severe non-neovascular AMD with a relative sparing of the foveal region. All the patients were randomly assigned in placebo or in treatment group. The treatment consisted of 10 sessions of 10-min each, using the new device comprised of micro-LEDs that emitted light onto an amorphous support assembled within Metallic eyeglasses. The placebo group blindly underwent the same number of PBM sessions with the micro-LED turned off. Before and after each placebo/treatment sessions all the patients received: optical coherence tomography (OCT), Best-Corrected Visual Acuity (BCVA) and Microperimetry (MP).Results no significant differences in the anatomical parameters were observed in the two groups. The MP mean sensitivity and the central visual function both far and near significantly improved in the treated group (respectively p< 0.001, p< 0.001)Conclusions our pivotal demonstrated that the LED PBM delivered through our new device is a safe and effective tool for improving short-term visual function in patients affected by severe non-neovascular AMD.

Centennial-scale increases of atmospheric carbon dioxide, known as carbon dioxide jumps, are identified during deglacial, glacial and interglacial periods and linked to the Northern Hemisphere abrupt climate variations. However, the limited number of identified carbon dioxide jumps prevents investigating the role of orbital background conditions on the different components of the global carbon cycle that may lead to such rapid atmospheric carbon dioxide releases. Here we present a high-resolution carbon dioxide record measured on an Antarctic ice core between 260,000 and 190,000 years ago, which reveals seven additional carbon dioxide Jumps. Eighteen of the 22 jumps identified over the past 500,000 years occurred under a context of high obliquity. Simulations performed with an Earth system model of intermediate complexity point towards both the Southern Ocean and the continental biosphere as the two main carbon sources during carbon dioxide jumps connected to Heinrich ice rafting events. Notably, the continental biosphere appears as the obliquity-dependent carbon dioxide source for these abrupt events. We demonstrate that the orbital-scale external forcing directly impacts past abrupt atmospheric carbon dioxide changes.

Despite the prevalence and importance of resting state thought for daily functioning and psychological well-being, it remains unclear how such thoughts differ between young and older adults. Age-related differences in the affective tone of resting state thoughts, including the affective language used to describe them, could be a novel manifestation of the positivity effect, with implications for well-being. To examine this possibility, a total of 77 young adults (M= 24.9 years, 18–35 years) and 74 cognitively normal older adults (M= 68.6 years, 58–83 years) spoke their thoughts freely during a think-aloud paradigm across two studies. The emotional properties of spoken words and participants’ retrospective self-reported affective experiences were computed and examined for age differences and relationships with psychological well-being. Study 1, conducted before the start of the COVID-19 pandemic, revealed that older adults exhibited more diversity of positive, but not negative, affectively tinged words compared to young adults and more positive self-reported thoughts. Despite being conducted virtually during the COVID-19 pandemic, study 2 replicated many of study 1’s findings, generalizing results across samples and study contexts. In an aggregated analysis of both samples, positive diversity predicted higher well-being beyond other metrics of affective tone, and the relationship between positive diversity and well-being was not moderated by age. Considering that older adults also exhibited higher well-being, these results hint at the possibility that cognitively healthy older adults’ propensity to experience more diverse positive concepts during natural periods of restful thought may partly underlie age-related differences in well-being and reveal a novel expression of the positivity effect.

A collection of papers presented at the 4th International Conference on Community Ecology.

Purpose: To investigate the impact of diabetes in immigrants on the Italian healthcare system, as well as their compliance with standard protocols of control and treatment. Methods: The prevalence of immigrants with diabetes living in the metropolitan area of Bologna (about 1 million inhabitants) in 2019 was investigated using a database containing all subjects in active follow-up for diabetes, based on antidiabetic drug use, disease-specific copayment exemption, ICD-9 codes, continuous care in diabetes units. Country of origin was derived from fiscal code. Results: The overall prevalence of diabetes (n = 53,941; 51.8% males, median age 64) was 6.1% in both Italy-born and immigrant cohorts. Immigrant prevalence was 12.4%, moderately higher than that observed in the total population (12.2%). Diabetes risk was increased in the whole immigrant cohort (odds ratio (OR) 1.74; 95% Confidence Interval (CI) 1.69–1.79). Among cases with incident diabetes, the proportion of immigrants (median age, 49 vs. 65 in Italy-born individuals) increased progressively from 11.7% to 26.5% from 2011 to 2019 (males, 8.9–21.0%; females, 14.9–32.8%) in all age groups, particularly in young adults, but also in older subjects. Metabolic control was lower in immigrants, as was adherence to shared diagnostic and therapeutic protocols, without systematic differences in antidiabetic drug use, but much lower use of drugs for comorbid conditions. Conclusions: The population with diabetes in the metropolitan area of Bologna is rapidly changing. Quality improvement initiatives are needed to reduce the burden for the universalistic Italian health care system generated by the rapidly-growing high-risk immigrant population.

A spilling breaker model (SBM) is implemented in an existing two-dimensional (2D) numerical wave tank (NWT), based on fully nonlinear potential flow (FNPF) theory and the boundary element method (BEM), in which an absorbing surface pressure is specified over the crest of impending breaking waves (detected based on a maximum front slope criterion) to simulate the power dissipated during breaking. The latter is calibrated to match that of a hydraulic jump of parameters identical to local wave properties (height, celerity, …). Although this model is not aimed at being fully physical in the surfzone, it allows more accurately simulating properties of fully nonlinear shoaling waves than standard empirical absorbing beaches (AB). After assessing the convergence with the discretization of 2D-NWT results for strongly nonlinear shoaling waves, simulations are first validated based on laboratory experiments for non-breaking and breaking waves, shoaling up a mild slope; a good agreement is found between both. The NWT is then used to compute fully nonlinear local (height, celerity, asymmetry) and integral (mean-water-level, radiation stress) properties of periodic waves shoaling over mild slopes. Discrepancies with standard results of wave theories are discussed in light of fully nonlinear effects modeled in the NWT. While only periodic waves are considered here, the SBM could be applied to shoaling irregular waves, for which the breaking point location will constantly vary, which would be advantageous compared to an AB fixed in space. For such cases, besides its more physical energy absorption, the SBM would allow better preventing wave overturning that may occur far from shore due to nonlinear wave–wave interactions and otherwise interrupt the FNPF–NWT simulations.

Conductors made of high-temperature (HTS) wires helically wound in one or more layers on round tubes (CORT) are compact, flexible, and can carry a large amount of current. Although these conductors were initially developed for DC applications, e.g., in magnets, it is worth considering their use for AC, e.g., in underground cables for medium voltage grids and with currents in the kA-range. In these cases, the major challenge is reducing AC losses. In contrast to a straight superconducting wire, in a helical arrangement, due to superconducting shielding, the current does not follow the direction of the wires, but takes a non-trivial zig-zag path within the individual HTS wires (Garber pattern). This includes current components across the thickness of the superconducting layers, so that the often used thin-shell approximation does not hold. In this contribution, we studied a one-layer three-wire CORT by means of fully three-dimensional simulations, based on the H-formulation of Maxwell's equations implemented in the commercial software package COMSOL Multiphysics. As a result of our simulations, the peculiar current profiles were confirmed. In addition, the influence of current, pitch angle, and frequency on the AC losses was studied. We found an optimum for the pitch angle and that the current profiles strongly depend on frequency.

The growth of international trade, coupled with an expansion of large-scale pine plantations in South America during the second half of the twentieth century, has significantly increased the opportunities for the invasion of forest insects. Bark beetles (Coleoptera: Curculionidae, Scolytinae) are a large and diverse group of insects, commonly recognized as one of the most important tree mortality agents in coniferous forests worldwide and an important group among invasive forest species. In this study, we combined data from field sampling with published records of established non-native pine bark beetles, to describe their distribution and invasion history in pine plantations across southern South America, reviewing the available information on their phenology and host range. We obtained records of established populations of six Eurasian species distributed in two major regions: the southwest region comprises plantations in Chile and the Argentine Patagonia, with four bark beetle species: Hylastes ater, Hylastes linearis, Hylurgus ligniperda, and Orthotomicus laricis; the northeastern zone includes northeastern Argentina, Uruguay, and southern Brazil, and includes three bark beetle species: Cyrtogenius luteus, H. ligniperda, and O. erosus. The establishment of non-native populations across the study area began in the 1950s, and from the 1980s onwards, there has been an exponential increase in introductions. We predict that several of these species will continue spreading across South America and that new species will continue arriving. We highlight the importance of international collaboration for early detection and management of non-native pine bark beetles.

Lithium Niobate is a ferroelectric material with interesting physical properties. In particular, Periodically Poled Lithium Niobate (PPLN) crystals have been used in diverse applications, such as non-linear optics or microlens array fabrication. In this work, we used a PPLN crystal having hexagonal reversed polarization domains, disposed on a square array of 200 µm period. We applied a temperature gradient to the PPLN and simultaneously observed it with a lensless incoherent holographic microscope. We observed that the phase of the inverse polarization domains varied depending on the temperature applied. Therefore, we induced a thermo-optical modulation of the PPLN crystal. We further analysed the behaviour of the PPLN, propagating the complex field beyond the crystal and plotting its intensity. We found that an elongated bright spot was formed at the centre of each hexagonal reversed polarization domain, due to diffraction. Given their shape and the nature of the phenomenon, these intensity spots are similar to Poisson spots. The intensity of the spots depended on the phase of the PPLN (hence, on the temperature applied). Therefore, we were able to generate a tunable Poisson spot array by controlling the temperature of the PPLN.

The laboratory mechanical characterisation of cold recycled materials mixtures is necessary to develop mechanistic-empirical design methods for cold recycled pavements. The present paper describes a laboratory experiment where small-scale specimens were used to characterise the complex modulus and fatigue properties of cement bitumen treated materials (CBTM) manufactured with bitumen emulsion and cement. In particular, CBTM specimens with diameter of 38 mm were tested and compared with two group of specimens with diameters of 100 and 75 mm. The complex modulus was measured by means of cyclic compression tests and then rheological modelling was applied. Fatigue tests were carried out in direct tension mode of loading. All tests were carried out at long-term curing conditions. Results and statistical analysis showed that the complex modulus values measured on large specimens (diameter of 100 and 75 mm), were not significantly different. On the other hand, the stiffness modulus values measured on small specimens (diameter of 38) were about 15% lower.

In many advanced applications, such as Tokamak fusion reactors, the twisted stacked tape cable (TSTC) configuration based on high-temperature-superconducting (HTS) tapes is one of the most promising one. Among the various designs proposed for the European DEMOnstration Fusion Power Plants (DEMO) magnets, several options include conductors based on the HTS-TSTC technology, especially for an Insert of the Central Solenoid (CS). An important main design criterion to be fulfilled by superconducting magnets in operation is related to the temperature margin, which should be lower than a given threshold. For a pulsed magnet as the CS, properly determining its value is only possible with a reliable knowledge of the instantaneous losses entering the superconducting cable. Previous works presented an analytical formulation for the computation of instantaneous magnetisation losses in a HTS-TSTC conductor during a generic cycle of transport current and external magnetic field in phase with each other. Further validation of these formulae is presented by comparison with a 2D numerical model. A complete analysis of a plasma scenario is impossible with this formulation, considering that transport current and external magnetic field are not jointly in phase during the plasma breakdown. This work presents an extension of the previously developed analytical formulae to the more realistic case where the magnetic field and the transport current are not in phase with each other. The new formulae are validated in a case study of technical interest, by comparison with a 1D numerical model suited for the computation of magnetisation losses in these conductors.

In the recent decades, sustainability has emerged as a crucial concern for governments and industries worldwide. While the political sphere appears to take the lead in the pursuit of a greener world from a societal standpoint, industries play a pivotal role in implementing innovative technologies. Certain industries, however, still heavily rely on natural gas consumption for their operations. Metal manufacturers, in particular, face significant energy demands due to their melting processes, which have historically necessitated the use of combustion. This paper focuses on examining the current workflow of secondary aluminum manufacturing, with a specific emphasis on rolled sheet production. By analyzing combustion intensive equipment involved in the process, the paper identifies inherent deficiencies and energy losses throughout the production process and propose strategies that can effectively reduce the industry's global carbon footprint. Results show that optimizing work flow to retain embodied energy and heat of intermediate products, as well as smart waste heat reuse can result in significant savings in secondary aluminum manufacturing.

The electrohydrodynamic (EHD) jetting of fluids is used for several applications such as inkjet printing, atomization of analyte in mass spectrometry, liquid metal alloy ion sources, and electrospinning of polymer fibers. Historically, the bulk of research has focused on nonviscous, highly conductive fluids which are most suitable for EHD spray and printing, while there is relatively little experimental work on EHD jetting of highly viscous liquid dielectrics. We studied the dynamics of oscillation and pulsating jetting from a suspended drop of polydimethylsiloxane (PDMS) polymers in an electric field, with particular attention to the viscosity dependence of the oscillation period and meniscus elongation and contraction time over a wide viscosity range (102–105cSt). The reported results could help the appropriate design of EHD processes and may open new possibilities for the rheological characterization of liquid polymers using small volumes at the scale of nanoliters.

Adenovirus is a known cause of hepatitis in immunocompromised children, but not in immunocompetent children. In April, 2022, following multiple reports of hepatitis of unknown aetiology and adenovirus viraemia in immunocompetent children in the USA and UK, the US Centers for Disease Control and Prevention (CDC) and jurisdictional health departments initiated national surveillance of paediatric acute hepatitis of unknown aetiology. We aimed to describe the clinical and epidemiological characteristics of children identified with hepatitis of unknown aetiology between Oct 1, 2021, and Sept 30, 2022, in the USA and to compare characteristics of those who tested positive for adenovirus with those who tested negative.

This article reviews Multilevel and Longitudinal Modeling Using Stata, Fourth Edition, by Rabe-Hesketh and Skrondal (2022, Stata Press).