Mohr circle-based graphical vibration analysis and earthquake response of asymmetric systems

The maximum seismic response of torsionally coupled plan asymmetric structures can be rationally visualized and computed through a Mohr Circle Response Spectrum Analysis (MCRSA). This is done combining the graphic modal properties of the torsional dynamic equations of motion with the structural earthquake demand in terms of a displacement spectrum as a function of the modal eigenvalues SD(ω2). A compact representation of the modal properties and of the response envelope is built and visualized in the Mohr plane. The maximum modal responses are then combined using a graphic adaptation of the SRSS and CCQ combination rules based on the elastic response spectrum. This Graphic Dynamic rule proves to be an effective response prediction tool, and is particularly suited to estimate the response of seismic base isolation systems

Daemonic ergotropy in continuously-monitored open quantum batteries

The amount of work that can be extracted from a quantum system can be increased by exploiting the information obtained from a measurement performed on a correlated ancillary system. The concept of daemonic ergotropy has been introduced to properly describe and quantify this work extraction enhancement in the quantum regime. We here explore the application of this idea in the context of continuously-monitored open quantum systems, where information is gained by measuring the environment interacting with the energy-storing quantum device. We first show that the corresponding daemonic ergotropy takes values between the ergotropy and the energy of the corresponding unconditional state. The upper bound is achieved by assuming an initial pure state and a perfectly efficient projective measurement on the environment, independently of the kind of measurement performed. On the other hand, if the measurement is inefficient or the initial state is mixed, the daemonic ergotropy is generally dependent on the measurement strategy. This scenario is investigated via a paradigmatic example of an open quantum battery: a two-level atom driven by a classical field and whose spontaneously emitted photons are continuously monitored via either homodyne, heterodyne, or photo-detection.Comment: 6 pages, 4 figure

Visual Stability During Saccades is Achieved through Transient Changes in Perceptual Space and Time

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Charging a quantum battery in a non-Markovian environment: a collisional model approach

We study the effect of non-Markovianity in the charging process of an open-system quantum battery. We employ a collisional model framework, where the environment is described by a discrete set of ancillary systems and memory effects in the dynamics can be introduced by allowing these ancillas to interact. We study in detail the behaviour of the steady-state ergotropy and the impact of the information backflow to the system on the different features characterizing the charging process. Remarkably, we find that there is a maximum value of the ergotropy achievable: this value can be obtained either in the presence of memoryless environment, but only in the large-loss limit, as derived in [D. Farina et al., Phys. Rev. B 99, 035421 (2019)], or in the presence of an environment with memory also beyond the large-loss limit. In general, we show that the presence of an environment with memory allows us to generate steady-state ergotropy near to its maximum value for a much larger region in the parameter space and thus potentially in a shorter time. Relying on the geometrical measure of non-Markovianity, we show that in both the cases of an environment with and without memory the ergotropy maximum is obtained when the non-Markovianity of the dynamics of the battery is zero, possibly as the result of a non-trivial interplay between the memory effects induced by, respectively, the environment and the charger connected to the battery

Quantum spin models for numerosity perception

Humans share with animals, both vertebrates and invertebrates, the capacity to sense the number of items in their environment already at birth. The pervasiveness of this skill across the animal kingdom suggests that it should emerge in very simple populations of neurons. Current modelling literature, however, has struggled to suggest a simple architecture carrying out this task, with most proposals suggesting the emergence of number sense in multi-layered complex neural networks, and typically requiring supervised learning. We present a simple quantum spin model with all-to-all connectivity, where numerosity is encoded in the spectrum after stimulation with a number of transient signals occurring in a random or orderly temporal sequence. We use a paradigmatic simulational approach borrowed from the theory and methods of open quantum systems out of equilibrium, as a possible way to describe information processing in neural systems. Our method is able to capture many of the perceptual characteristics of numerosity in such systems. The frequency components of the magnetization spectra at harmonics of the system's tunneling frequency increase with the number of stimuli presented. The amplitude decoding of each spectrum, performed with an ideal-observer model, reveals that the system follows Weber's law, one of the hallmarks of numerosity perception across the animal kingdom. This contrasts with the well-known failure to reproduce Weber's law with linear system or accumulators models.Comment: 19 pages, 9 figure

Visual BOLD Response in Late Blind Subjects with Argus II Retinal Prosthesis

Retinal prosthesis technologies require that the visual system downstream of the retinal circuitry be capable of transmitting and elaborating visual signals. We studied the capability of plastic remodeling in late blind subjects implanted with the Argus II Retinal Prosthesis with psychophysics and functional MRI (fMRI). After surgery, six out of seven retinitis pigmentosa (RP) blind subjects were able to detect high-contrast stimuli using the prosthetic implant. However, direction discrimination to contrast modulated stimuli remained at chance level in all of them. No subject showed any improvement of contrast sensitivity in either eye when not using the Argus II. Before the implant, the Blood Oxygenation Level Dependent (BOLD) activity in V1 and the lateral geniculate nucleus (LGN) was very weak or absent. Surprisingly, after prolonged use of Argus II, BOLD responses to visual input were enhanced. This is, to our knowledge, the first study tracking the neural changes of visual areas in patients after retinal implant, revealing a capacity to respond to restored visual input even after years of deprivation

A case of furuncular myiasis in an Italian patient: a "travel souvenir"

Furuncular myiasis is a parasitosis of the skin that is commonly reported in the tropical areas and is caused by various agents including Dermatobia hominis. Knowledge of myiasis is limited in Italy, resulting in difficulties in its diagnosis and treatment. We report a case of imported furuncular myiasis in a 48 year old Italian patient who returned from Peru. A third stage larva of D. hominis was identified and the diagnosis of myiasis was confirmed

How to integrate surgery and targeted therapy with biologics for the treatment of hidradenitis suppurativa: Delphi consensus statements from an Italian expert panel

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease characterized by recurrent and painful nodules and abscesses in intertriginous skin areas, which can progress to sinus tract formation, tissue destruction, and scarring. HS is highly debilitating and severely impairs the psychological well-being and quality of life of patients. The therapeutic approach to HS is based on medical therapy and surgery. First-line medical therapy includes topical antibiotics, systemic antibiotics, and biologics. Main surgical procedures include deroofing, local excision, and wide local excision. Despite the availability of multiple therapeutic options, the rates of disease recurrence and progression continue to be high. In recent years, the possibility of combining biologic therapy and surgery has raised considerable interest. In a clinical trial, the perioperative use of adalimumab has been associated with greater response rates and improved inflammatory load and pain, with no increased risk of postoperative infectious complications. However, several practical aspects of combined biologic therapy and surgery are poorly defined. In June 2022, nine Italian HS experts convened to address issues related to the integration of biologic therapy and surgery in clinical practice. To this purpose, the experts identified ten areas of interest based on published evidence and personal experience: 1) patient profiling (diagnostic criteria, disease severity classification, assessment of response to treatment, patient-reported outcomes, comorbidities); 2) tailoring surgery to HS characteristics; 3) wide local excision; 4) pre-surgery biologic treatment; 5) concomitant biologic and surgical treatments; 6) pre- and post-surgery management; 7) antibiotic systemic therapy; 8) biologic therapy after radical surgery; 9) management of adverse events to biologics; 10) management of postoperative infectious complications. Consensus between experts was reached using the Estimate-Talk-Estimate method (Delphi Method). The statements were subsequently presented to a panel of 27 HS experts from across Italy, and their agreement was assessed using the UCLA Appropriateness Method. This article presents and discusses the consensus statements

Perspectives in noninvasive imaging for chronic coronary syndromes

Both the latest European guidelines on chronic coronary syndromes and the American guidelines on chest pain have underlined the importance of noninvasive imaging to select patients to be referred to invasive angiography. Nevertheless, although coronary stenosis has long been considered the main determinant of inducible ischemia and symptoms, growing evidence has demonstrated the importance of other underlying mechanisms (e.g., vasospasm, microvascular disease, energetic inefficiency). The search for a pathophysiology-driven treatment of these patients has therefore emerged as an important objective of multimodality imaging, integrating "anatomical" and "functional" information. We here provide an up-to-date guide for the choice and the interpretation of the currently available noninvasive anatomical and/or functional tests, focusing on emerging techniques (e.g., coronary flow velocity reserve, stress-cardiac magnetic resonance, hybrid imaging, functional-coronary computed tomography angiography, etc.), which could provide deeper pathophysiological insights to refine diagnostic and therapeutic pathways in the next future