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The emergence of collective order in matter is among the most fundamental and intriguing phenomena in physics. In recent years, the dynamical control and creation of novel ordered states of matter not accessible in thermodynamic equilibrium is receiving much attention1–6. The theoretical concept of dynamical multiferroicity has been introduced to describe the emergence of magnetization due to time-dependent electric polarization in non-ferromagnetic materials7,8. In simple terms, the coherent rotating motion of the ions in a crystal induces a magnetic moment along the axis of rotation. Here we provide experimental evidence of room-temperature magnetization in the archetypal paraelectric perovskite SrTiO3 due to this mechanism. We resonantly drive the infrared-active soft phonon mode with an intense circularly polarized terahertz electric field and detect the time-resolved magneto-optical Kerr effect. A simple model, which includes two coupled nonlinear oscillators whose forces and couplings are derived with ab initio calculations using self-consistent phonon theory at a finite temperature9, reproduces qualitatively our experimental observations. A quantitatively correct magnitude was obtained for the effect by also considering the phonon analogue of the reciprocal of the Einstein–de Haas effect, which is also called the Barnett effect, in which the total angular momentum from the phonon order is transferred to the electronic one. Our findings show a new path for the control of magnetism, for example, for ultrafast magnetic switches, by coherently controlling the lattice vibrations with light.We demonstrate the emergence of magnetism induced by a terahertz electric field in SrTiO3. [ABSTRACT FROM AUTHOR]

Introduction: Admission to an intensive care unit can cause sequelae to both patients and family members. In some countries, the use of diaries is a preventive action., Aim: This research proposes to critically examine the concept of 'Intensive Care Unit Diary' by analysing the current state of the scientific literature to develop a precise conception of this phenomenon in nursing practice, since there are multiple unknowns regarding its use and content., Method: A bibliographic search was carried out in the PubMed, Cochrane Library, Scopus and CINAHL databases in January 2023. The terms used to search for their use and definitions in the databases included Nurse, Concept analysis, Family, Uci Diary, Patient Critical, Intensive Care Unit. We use Wilson's concept analysis, later developed by Walker and Avant., Results: The concept analysis shows that the 'ICU Diary' is a record made in colloquial language by health workers and relatives of the patient admitted to the intensive care unit. Aimed at the patient, with an empathic and reflective style, which offers a narrative of the process, daily life and the conduct or behaviour of the patient during his stay. It is a therapeutic tool led by nurses accepted by patients, families and professionals. Its use benefits the recovery process, reducing post-traumatic stress in family members and patients. It favours communication and the bond between nurses, family members and patients, helping to express feelings and emotions., Conclusions: The concept of 'UCI Diary' is complex. Through Wilson's model, a clarification of the concept has been achieved, creating a starting point for more precise research on this phenomenon and its effects on patients, family members, professionals and the health system., (Copyright © 2023 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Published by Elsevier España S.L.U. All rights reserved.)

Recently developed terahertz (THz) two-dimensional coherent spectroscopy (2DCS) is a powerful technique to obtain materials information in a fashion qualitatively different from other spectroscopies. Here, we utilized THz 2DCS to investigate the THz nonlinear response of conventional superconductor NbN. Using broadband THz pulses as light sources, we observed a third-order nonlinear signal whose spectral components are peaked at twice the superconducting gap energy 2Δ. With narrow-band THz pulses, a THz nonlinear signal was identified at the driving frequency Ω and exhibited a resonant enhancement at temperature when Ω=2Δ. General theoretical considerations show that such a resonance can arise only from a disorder-activated paramagnetic coupling between the light and the electronic current. This proves that the nonlinear THz response can access processes distinct from the diamagnetic Raman-like density fluctuations, which are believed to dominate the nonlinear response at optical frequencies in metals. Our numerical simulations reveal that, even for a small amount of disorder, the Ω=2Δ resonance is dominated by the superconducting amplitude mode over the entire investigated disorder range. This is in contrast to other resonances, whose amplitude-mode contribution depends on disorder. Our findings demonstrate the unique ability of THz 2DCS to explore collective excitations inaccessible in other spectroscopies.

Ultrafast optical control of quantum systems is an emerging field of physics. In particular, the possibility of light-driven superconductivity has attracted much of attention. To identify nonequilibrium superconductivity, it is necessary to measure fingerprints of superconductivity on ultrafast timescales. Recently, nonlinear THz third-harmonic generation (THG) was shown to directly probe the collective degrees of freedoms of the superconducting condensate, including the Higgs mode. Here, we extend this idea to light-driven nonequilibrium states in superconducting La 2- x Sr x CuO 4 , establishing an optical pump-THz-THG drive protocol to access the transient superconducting order-parameter quench and recovering on few-picosecond timescales. We show in particular the ability of two-dimensional TH spectroscopy to disentangle the effects of optically excited quasiparticles from the pure order-parameter dynamics, which are unavoidably mixed in the pump-driven linear THz response. Benchmarking the gap dynamics to existing experiments shows the ability of driven THG spectroscopy to overcome these limitations in ordinary pump-probe protocols.

Recent experiments with strong THz fields in unconventional cuprate superconductors have clearly evidenced an increase of the non-linear optical response below the superconducting critical temperature T c . As in the case of conventional superconductors, a theoretical estimate of the various effects contributing to the non-linear response is needed in order to interpret the experimental findings. Here, we report a detailed quantitative analysis of the non-linear THz optical kernel in cuprates within a realistic model, accounting for the band structure and disorder level appropriate for these systems. We show that the BCS quasiparticle response is the dominant contribution for cuprates, and its polarization dependence accounts very well for the third-harmonic generation measurements. On the other hand, the polarization dependence of the THz Kerr effect is only partly captured by our calculations, suggesting the presence of additional effects when the system is probed using light pulses with different central frequencies.

Objective: The Results Centre's (RC) mission is to measure, evaluate and disseminate the results achieved by the different agents of the health system, based on relevant measures. The purpose of this research is to describe the evolution of indicators used in the social and health care network RC (RC-SH), including some indicators sensitive to nursing practice., Method: Observational, descriptive cross-sectional study based on data from 6 RC-SH reports (2013-2018). Indicators including activity carried out, days of stay, achievement of rehabilitation goals, discharge to home, mortality and pressure ulcers are analysed., Results: There was an increase in activity on the different social and health resources and days of stay decrease. Results were heterogeneous between centres. Functional improvement and home discharge showed an increasing trend, while mortality tended to decrease. The prevalence of grade III-IV pressure ulcers was maintained., Conclusions: RC-SH reports have included different indicators to improve the capacity of evaluation and benchmarking for social and health network. These reports provide transparency and accountability in the field and invite further improvement in this sector. Also RC-SH results show that social and health network evolves towards intermediate care with the entry of subacute resources and the greater efficiency of convalescence. The incorporation of indicators sensitive to nursing practice contributes to making nurses and nursing care visible., (Copyright © 2022 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.)

One of the consequences of the COVID-19 lockdowns has been the modification of the air quality in many cities around the world. This study focuses on the variations in pollutant concentrations and how important meteorological conditions were for those variations in Barcelona and the surrounding area during the 2020 lockdown. Boundary-layer height, wind speed, and precipitation were compared between mid-March and April 2016-2019 (pre-lockdown) and the same period in 2020 (during lockdown). The results show the limited influence of meteorological factors on horizontal and vertical dispersion conditions. Compared with the pre-lockdown period, during lockdown the boundary-layer height slightly increased by between 5% and 9%, mean wind speed was very similar, and the fraction of days with rainfall increased only marginally, from 0.33 to 0.34, even though April 2020 was extremely wet in the study area. Variations in nitrogen dioxide ( NO 2 ), particulate matter with a diameter less than 10 μ m (PM10), and ozone ( O 3 ) concentrations over a 10-year period showed a 66% reduction in NO 2 , 37% reduction in PM10, and 27% increase in O 3 at a traffic station in Barcelona. The differences in the daily concentration cycle between weekends and weekdays were heavily smoothed for all pollutants considered. The afternoon NO 2 peak at the traffic station was suppressed compared with the average daily cycle. The analysis of ozone was extended to the regional scale, revealing lower concentrations at rural sites and higher ones in urban zones, especially in Barcelona and the surrounding area. The results presented not only complement previous air quality COVID-19 lockdown studies but also provide insights into the effects of road-traffic reduction., (© The Author(s) 2021.)