A novel automata-theoretic approach to timeline-based planning

Timeline-based planning is a well-established approach successfully employed in a number of application domains. A very restricted fragment, featuring only bounded temporal relations and token durations, is expressive enough to capture action-based temporal planning. As for computational complexity, it has been shown to be EXPSPACE-complete when unbounded temporal relations, but only bounded token durations, are allowed. In this paper, we present a novel automata-theoretic characterisation of timeline-based planning where the existence of a plan is shown to be equivalent to the nonemptiness of the language recognised by a nondeterministic finite-state automaton that suitably encodes all the problem constraints (timelines and synchronisation rules). Besides allowing us to restate known complexity results in a fairly natural and compact way, such an alternative characterisation makes it possible to finally establish the exact complexity of the full version of the problem with unbounded temporal relations and token durations, which was still open and turns out to be EXPSPACE-complete. Moreover, the proposed technique is general enough to cope with (infinite) recurrent goals, which received little attention so far, despite being quite common in real-word application scenarios

Record of thermoluminescence in sea sediments in the last millennia

The profile of thermoluminescence (TL) has been measured in the Ionian shallow-water core GT89-3 with a resolution of 3.096 years (corresponding to a sampling interval of 2 mm) during the last 1800 years. A similar TL record was previously obtained in the core GT14, taken from the same area, with a resolution of 3.87 years (corresponding to a sampling interval of 2.5 mm). We present here the comparison of the TL profiles. We confirm the presence of the centennial and the decennial cycles earlier identified in the TL signal, corresponding to cyclicities appearing to exist in the solar-activity records. We discuss the origin of the TL signal by comparison with the cosmogenic isotopes 14C and 10Be records

Decidability and complexity of the fragments of the modal logic of Allen's relations over the rationals

Interval temporal logics provide a natural framework for temporal reasoning about interval structures over linearly ordered domains, where intervals are taken as first-class citizens. Their expressive power and computational behaviour mainly depend on two parameters: the set of modalities they feature and the linear orders over which they are interpreted. In this paper, we consider all fragments of Halpern and Shoham's interval temporal logic hs with a decidable satisfiability problem over the rationals, and we provide a complete classification of them in terms of their expressiveness and computational complexity by solving the last few open problems

On the solar origin of the 200 y Suess wiggles: Evidence from thermoluminescence in sea sediments

In order to understand the origin of the Suess wiggles, present in the tree ring 14C record, we have studied the thermoluminescence (TL) of a shallow-water Ionian sea core, in an attempt to provide a record of an indicator responding to the solar output more promptly than 14C in tree rings. The spectral content of the TL and radiocarbon records is very similar; neverthless, in addition to the 207 y Suess wave (A43.6% ), the TL record shows the second harmonic (103.5 y; A42.4% ), in phase with the envelope of the 11 y solar cycles. This result, obtained by different spectral methods, in particular by Superposition of Epochs (SE) and by Singular Spectrum Analysis (SSA), strongly supports the solar origin of the 200 y Suess wiggles

The impact of Covid-19 healthcare emergency on the psychological well-being of health professionals: a review of literature

Introduction. The Coronavirus pandemic (Covid-19) was first identified in December 2019 in the city of Wuhan, China, and later caused a severe health crisis, causing massive disruptions to most healthcare systems worldwide. The Covid-19 health emergency has seen healthcare workers in the front line facing all the difficulties related to the care burden. One of the most significant and probably underinvestigated aspects is the psychological stress of the healthcare staff managing the emergency. The aim of the paper is to analyze the literature on the impact of the Covid-19 crisis on the psychological well-being of health professionals. Methodology. We conducted a systematic review of articles published on this topic during the months from January 2020 to December 2020, searching on Pub Med, Scopus and Web of Science databases. Results. Most of the issues can be summarized into five conceptual categories: Stress, Depression and Infection Anxiety, Anguish, Insomnia, Post Traumatic Stress Disorder, and Suicide. The literature identifies many factors contributing to the onset of anxiety, depression, and stress, like the fear of contracting the disease and transmitting it to family members and friends, stressful shifts, and little rest among several others. The literature highlights the needs for adequate measures, including proper psychological support. Conclusion. The conducted review suggests that the behaviours of healthcare professionals during the emergency phase of the Covid-19 pandemic show psychological disorders that can compromise mental health. Therefore, there is a call for those in chief like hospital managers and policymakers to take action, promoting measures like surveillance, monitoring, and psychological support among others, to increase the resilience of healthcare workers, limiting stress and anxiety and allowing them to keep their performance at work

The impact of Covid-19 healthcare emergency on the psychological well-being of health professionals: a review of literature

Introduction. The Coronavirus pandemic (Covid-19) was first identified in December 2019 in the city of Wuhan, China, and later caused a severe health crisis, causing massive disruptions to most healthcare systems worldwide. The Covid-19 health emergency has seen healthcare workers in the front line facing all the difficulties related to the care burden. One of the most significant and probably underinvestigated aspects is the psychological stress of the healthcare staff managing the emergency. The aim of the paper is to analyze the literature on the impact of the Covid-19 crisis on the psychological well-being of health professionals.Methodology. We conducted a systematic review of articles published on this topic during the months from January 2020 to December 2020, searching on Pub Med, Scopus and Web of Science databases.Results. Most of the issues can be summarized into five conceptual categories: Stress, Depression and Infection Anxiety, Anguish, Insomnia, Post Traumatic Stress Disorder, and Suicide. The literature identifies many factors contributing to the onset of anxiety, depression, and stress, like the fear of contracting the disease and transmitting it to family members and friends, stressful shifts, and little rest among several others. The literature highlights the needs for adequate measures, including proper psychological support.Conclusion. The conducted review suggests that the behaviours of healthcare professionals during the emergency phase of the Covid-19 pandemic show psychological disorders that can compromise mental health. Therefore, there is a call for those in chief like hospital managers and policymakers to take action, promoting measures like surveillance, monitoring, and psychological support among others, to increase the resilience of healthcare workers, limiting stress and anxiety and allowing them to keep their performance at work

Are nonsingular black holes with super-Planckian hair ruled out by S2 star data?

We propose a novel nonsingular black-hole spacetime representing a strong deformation of the Schwarzschild solution with mass $M$ by an additional hair $\ell$, which may be hierarchically larger than the Planck scale. Our black-hole model presents a de Sitter core and $\mathcal{O}(\ell^2/r^2)$ slow-decaying corrections to the Schwarzschild solution. Our black-hole solutions are thermodynamically preferred when $0.2 \lesssim \ell/GM \lesssim \, 0.3$ and are characterized by strong deviations in the orbits of test particles from the Schwarzschild case. In particular, we find corrections to the perihelion precession angle scaling linearly with $\ell$. We test our model using the available data for the orbits of the S2 star around $\text{SgrA}^*$. These data strongly constrain the value of the hair $\ell$, casting an upper bound on it of $\sim \, 0.47 \, GM$, but do not rule out the possible existence of regular black holes with super-Planckian hair.Comment: 6 pages, 2 figures, 1 table. Revised version: Addendum and some references have been adde

Assessing a sleep interviewing chatbot to improve subjective and objective sleep: protocol for an observational feasibility study

BACKGROUND: Sleep disorders are common among the aging population and people with neurodegenerative diseases. Sleep disorders have a strong bidirectional relationship with neurodegenerative diseases, where they accelerate and worsen one another. Although one-to-one individual cognitive behavioral interventions (conducted in-person or on the internet) have shown promise for significant improvements in sleep efficiency among adults, many may experience difficulties accessing interventions with sleep specialists, psychiatrists, or psychologists. Therefore, delivering sleep intervention through an automated chatbot platform may be an effective strategy to increase the accessibility and reach of sleep disorder intervention among the aging population and people with neurodegenerative diseases. OBJECTIVE: This work aims to (1) determine the feasibility and usability of an automated chatbot (named MotivSleep) that conducts sleep interviews to encourage the aging population to report behaviors that may affect their sleep, followed by providing personalized recommendations for better sleep based on participants' self-reported behaviors; (2) assess the self-reported sleep assessment changes before, during, and after using our automated sleep disturbance intervention chatbot; (3) assess the changes in objective sleep assessment recorded by a sleep tracking device before, during, and after using the automated chatbot MotivSleep. METHODS: We will recruit 30 older adult participants from West London for this pilot study. Each participant will have a sleep analyzer installed under their mattress. This contactless sleep monitoring device passively records movements, heart rate, and breathing rate while participants are in bed. In addition, each participant will use our proposed chatbot MotivSleep, accessible on WhatsApp, to describe their sleep and behaviors related to their sleep and receive personalized recommendations for better sleep tailored to their specific reasons for disrupted sleep. We will analyze questionnaire responses before and after the study to assess their perception of our proposed chatbot; questionnaire responses before, during, and after the study to assess their subjective sleep quality changes; and sleep parameters recorded by the sleep analyzer throughout the study to assess their objective sleep quality changes. RESULTS: Recruitment will begin in May 2023 through UK Dementia Research Institute Care Research and Technology Centre organized community outreach. Data collection will run from May 2023 until December 2023. We hypothesize that participants will perceive our proposed chatbot as intelligent and trustworthy; we also hypothesize that our proposed chatbot can help improve participants' subjective and objective sleep assessment throughout the study. CONCLUSIONS: The MotivSleep automated chatbot has the potential to provide additional care to older adults who wish to improve their sleep in more accessible and less costly ways than conventional face-to-face therapy. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/45752

Heliospheric behavior in the past by Titanium-44 measurement in chondrites

This article does not have an abstract

An Optimal Decision Procedure for MPNL over the Integers

Interval temporal logics provide a natural framework for qualitative and quantitative temporal reason- ing over interval structures, where the truth of formulae is defined over intervals rather than points. In this paper, we study the complexity of the satisfiability problem for Metric Propositional Neigh- borhood Logic (MPNL). MPNL features two modalities to access intervals "to the left" and "to the right" of the current one, respectively, plus an infinite set of length constraints. MPNL, interpreted over the naturals, has been recently shown to be decidable by a doubly exponential procedure. We improve such a result by proving that MPNL is actually EXPSPACE-complete (even when length constraints are encoded in binary), when interpreted over finite structures, the naturals, and the in- tegers, by developing an EXPSPACE decision procedure for MPNL over the integers, which can be easily tailored to finite linear orders and the naturals (EXPSPACE-hardness was already known).Comment: In Proceedings GandALF 2011, arXiv:1106.081