New Insights into the Charge-Transfer-to-Solvent Spectrum of Aqueous Iodide: Surface versus Bulk.

Liquid phase charge-transfer-to-solvent (CTTS) transitions are important, as they serve as photochemical routes to solvated electrons. In this work, broadband deep-ultraviolet electronic sum frequency generation (DUV-ESFG) and two-photon absorption (2PA) spectroscopic techniques were used to assign and compare the nature of the aqueous iodide CTTS excitations at the air/water interface and in bulk solution. In the one-photon absorption (1PA) spectrum, excitation to the 6s Rydberg-like orbital (5p → 6s) gives rise to a pair of spin-orbit split iodine states, 2P3/2 and 2P1/2. In the 2PA spectra, the lower-energy 2P3/2 peak is absent and the observed 2PA peak, which is ∼0.14 eV blue-shifted relative to the upper 2P1/2 CTTS peak seen in 1PA, arises from 5p → 6p electronic promotion. The band observed in the ESFG spectrum is attributed to mixing of excited states involving 5p → 6p and 5p → 6s promotions caused by both vibronic coupling and the external electric field generated by asymmetric interfacial solvation

Validation of an Emission Model for a Marine Diesel Engine with Data from Sea Operations

In this study, a model is developed to simulate the dynamics of an internal combustion engine, and it is calibrated and validated against reliable experimental data, making it a tool that can effectively be adopted to conduct emission predictions. In this work, the Ricardo WAVE software is applied to the simulation of a particular marine diesel engine, a four-stroke engine used in the maritime field. Results from the bench tests are used for the calibration of the model. Finally, the calibration of the model and its validation with full-scale data measured at sea are presented. The prediction includes not only the classic engine operating parameters for a comparison with surveys but also an estimate of nitrogen oxide emissions, which are compared with similar results obtained with emission factors. The calibration of the model made it possible to obtain an overlap between the simulation results and real data with an average error of approximately 7% on power, torque, and consumption. The model provides encouraging results, suggesting further applications, such as in the study on transient conditions, coupling of the engine model with the ship model for a complete simulation of the operating conditions, and optimization studies on consumption and emissions. The availability of the emission data during the sea trial and validated simulation results are the strengths and novelties of this work

Are inner disc misalignments common? ALMA reveals an isotropic outer disc inclination distribution for young dipper stars

Dippers are a common class of young variable star exhibiting day-long dimmings with depths of up to several tens of per cent. A standard explanation is that dippers host nearly edge-on (id ≈ 70°) protoplanetary discs that allow close-in (10 au) disc resolved by ALMA and that inner disc misalignments may be common during the protoplanetary phase. More than one mechanism may contribute to the dipper phenomenon, including accretion-driven warps and ‘broken’ discs caused by inclined (sub-)stellar or planetary companions

Understanding the Impact of Individual Creativity with Information Technology upon the Deep Usage of IT Systems

In today’s competitive business world, creativity is an important component in enhancing an organization’s ability to retain its competitive advantage and stay ahead of competitors. In order to exploit creativity, firms must learn to identify and leverage it across all levels of the organization. Nonetheless, despite the importance of creativity, no work to date has conceptualized individual creativity with IT, nor studied the impact of creativity with IT upon the deep usage of IT systems. In this paper, we report the results of a study involving 111 users of an Electronic Document System that finds creativity to be a stronger driver of the creation of novel and useful ideas about IT than innovation or self-efficacy. By extension, it was a stronger predictor of the deep usage of IT even after accounting for perceptions towards the IT

Optimal force evaluation for isotonic fatigue characterization in mouse Tibialis Anterior muscle

Skeletal muscle fatigue is most often studied as a response to repeated stimulations in isometric conditions and it is usually quantified as the progressive loss of force generating capability over time. However, physical dynamic activity is based on the shortening of skeletal muscles. Therefore, the condition that best mimics body movements is the isotonic one, in which muscle is allowed to shorten against a constant load. In the literature, the isotonic fatigue test is performed allowing the muscle to lift a load corresponding to one-third of the maximal isometric force (reference optimal force), as best representative of the force at which the tissue develops its maximum power. The goal of this study was to devise a new testing protocol in which each muscle was tested for isotonic fatigue by shortening against its own optimal force, i.e. the force at which it really developed the maximum power. Our hypothesis was that testing all the muscle at a standard reference value would introduce significant errors in the parameters associated to muscle fatigue and in their variance. The proposed protocol was based on the real-time measurement of the maximum power a muscle was able to generate through the application of the after-load technique and a mathematical interpolation to the Hill's equation, that therefore allowed to determine the experimental optimal force to be applied during the fatigue test. Experimental results showed that the muscles tested with the experimental optimal force had a fatigue time significantly lower than the control muscles tested with the reference optimal force. A decrease, even if not statistically significant, was also measured for the power and work generated during the fatigue test. Of note, for all these parameters a huge decrease in the measurement variance was reported, confirming that a precise assessment of the muscle experimental optimal force was needed to increase the accuracy of the measurements. On the other hand, the application of the protocol proposed in this work required an increase in the test duration, due to the application of the after-load technique, and a real time measurement of the power generated by the tissue

A wearable heart rate measurement device for children with autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by early impairment in social and communication domains and autonomic nervous system unbalance. This study evaluated heart rate (HR) as a possible indicator of stress response in children with ASD as compared to children with language disorder (LD). Twenty-four patients [mean age = 42.62 months; SD = 8.14 months,12 with ASD (10 M/2F) and 12 with LD (8 M/4F)] underwent clinical [Leiter International Performance Scale-Revised, Autism Diagnostic Observation Schedule, second edition (ADOS-2)] and physiological evaluation (HR monitoring) during five interactive activities, while wearing an HR measurement device. IQ (ASD:IQ = 103.33 ± 12.85 vs. LD:IQ = 111.00 ± 8.88, p = 0.103) and fluid reasoning on the Leiter-R Scale were within the normal range in all subjects. Increased HR during the third activity (ADOS-2 bubble play) significantly correlated with autistic symptoms (r = 0.415; p = 0.044), while correlations between ADOS-2 total score and HR during the first activity (ADOS-2 free play; r = 0.368; p = 0.077), second activity (Leiter-R figure ground subscale; r = 0.373, p = 0.073), and fifth activity (ADOS-2 anticipation of a routine with objects; r = 0.368; p = 0.076) did not quite reach statistical significance. Applying a linear regression model, we found that the ADOS-2 total score significantly influenced HR variations (p = 0.023). HR monitoring may provide a better understanding of the stress-provoking situations for children with ASD. Furthermore, it could help clinicians detect the impact of the stressful condition on the autistic core and adress treatment strategy

Laryngectomized patients caregivers' life experience: A phenomenological study

Background: Laryngectomized patients often depend on their caregivers who have a central and difficult role in supporting them dealing with financial, social, and relational issues. In fact, they feel very responsible and committed, especially considering the time devoted to take care of their beloved. Besides, providing care induces caregivers high stress levels, emotional distress, anxiety and the fear of cancer recurrence or progress. Few studies investigated laryngectomized patients caregivers\u2019 life experience during both the whole course of illness and at the end of the treatment. Therefore, the purpose of our study was to explore, through a phenomenological approach, the lived-experience of primary family caregivers of laryngectomized patients undergoing radical surgery. Methods: Qualitative semi-structured and audiotaped interviews were held with 12 laryngectomized patients\u2019 primary family caregivers. Data were analysed using the descriptive phenomenological approach outlined by Colaizzi. Results: Three key themes emerged: the caregivers lived experience of illness; the change of caregivers\u2019 daily life and how they support their sick beloved. The experience of caregivers\u2019 lived relations changes from being a family member to a supportive carer, and the illness of their beloved negatively affects their psychological lived experience. Their perception of time and Quality of Life change as their perception of the future becomes uncertain. Finally, they feel guilty mainly because of the limited amount of time they can devote to their beloved. Conclusions: The study findings allowed to understand in depth how the presence of a laryngectomized person in the family may affect the life of the caregiver, even after the treatment phase. This suggests the need for healthcare professionals to support caregivers throughout the whole care journey and especially in dealing with the perception of time during the diagnosis and care phases. Further research should be conducted on factors contributing to time perception alteration and possible interventions to support caregivers to cope with it

K2-231 b: A sub-Neptune exoplanet transiting a solar twin in Ruprecht 147

We identify a sub-Neptune exoplanet ($R_p = 2.5 \pm 0.2$ R$_\oplus$) transiting a solar twin in the Ruprecht 147 star cluster (3 Gyr, 300 pc, [Fe/H] = +0.1 dex). The ~81 day light curve for EPIC 219800881 (V = 12.71) from K2 Campaign 7 shows six transits with a period of 13.84 days, a depth of ~0.06%, and a duration of ~4 hours. Based on our analysis of high-resolution MIKE spectra, broadband optical and NIR photometry, the cluster parallax and interstellar reddening, and isochrone models from PARSEC, Dartmouth, and MIST, we estimate the following properties for the host star: $M_\star = 1.01 \pm 0.03$ M$_\odot$, $R_\star= 0.95 \pm 0.03$ R$_\odot$, and $T_{\rm eff} = 5695 \pm 50$ K. This star appears to be single, based on our modeling of the photometry, the low radial velocity variability measured over nearly ten years, and Keck/NIRC2 adaptive optics imaging and aperture-masking interferometry. Applying a probabilistic mass-radius relation, we estimate that the mass of this planet is $M_p = 7 +5 -3$ M$_\oplus$, which would cause a RV semi-amplitude of $K = 2 \pm 1$ m s$^{-1}$ that may be measurable with existing precise RV facilities. After statistically validating this planet with BLENDER, we now designate it K2-231 b, making it the second sub-stellar object to be discovered in Ruprecht 147 and the first planet; it joins the small but growing ranks of 23 other planets found in open clusters.Comment: 24 pages, 7 figures, light curve included as separate fil

Dynamical Casimir-Polder interaction between an atom and surface plasmons

We investigate the time-dependent Casimir-Polder potential of a polarizable two-level atom placed near a surface of arbitrary material, after a sudden change in the parameters of the system. Different initial conditions are taken into account. For an initially bare ground-state atom, the time-dependent Casimir-Polder energy reveals how the atom is "being dressed" by virtual, matter-assisted photons. We also study the transient behavior of the Casimir-Polder interaction between the atom and the surface starting from a partially dressed state, after an externally induced change in the atomic level structure or transition dipoles. The Heisenberg equations are solved through an iterative technique for both atomic and field operators in the medium-assisted electromagnetic field quantization scheme. We analyze in particular how the time evolution of the interaction energy depends on the optical properties of the surface, in particular on the dispersion relationof surface plasmon polaritons. The physical significance and the limits of validity of the obtained results are discussed in detail.Comment: 12 pages, 8 figure