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Experimental characterization of the structural, electronic and dynamic properties of dilute systems in aqueous solvents, such as nanoparticles, molecules and proteins, are nowadays an open challenge. X-ray absorption spectroscopy (XAS) is probably one of the most established approaches to this aim as it is element-specific. However, typical dilute systems of interest are often composed of light elements that require extreme-ultraviolet to soft X-ray photons. In this spectral regime, water and other solvents are rather opaque, thus demanding radical reduction of the solvent volume and removal of the liquid to minimize background absorption. Here, we present an experimental endstation designed to operate a liquid flat jet of sub-micrometre thickness in a vacuum environment compatible with extreme ultraviolet/soft XAS measurements in transmission geometry. The apparatus developed can be easily connected to synchrotron and free-electron-laser user-facility beamlines dedicated to XAS experiments. The conditions for stable generation and control of the liquid flat jet are analyzed and discussed. Preliminary soft XAS measurements on some test solutions are shown.

Experimental studies based on the body specificity hypothesis revealed associations between affective valence and hand dominance (i.e., dominant hand—positive; non-dominant hand—negative), or lateral movements of the hands (i.e., dominant hand toward the ipsilateral space—positive; dominant hand toward the controlateral space—negative). Interestingly , these associations have never been investigated in a response time paradigm with a swipe gesture. In two experiments we presented on a touchscreen device 16 images (previously valenced in a manipulation check experiment) to 24 right-handers (Exp. 1) and 24 lefthanders participants (Exp.2), asking them to make valence judgments in both a congruent (swipe toward dominant space to positive images, vice versa for negative images) and incongruent (the opposite) task. Results highlighted that both right-handers and left handers were faster (p<0.001) in the congruent condition in respect to the incongruent condition; this effect was only present in evaluations made with the dominant hand, supporting the idea that space-valence associations (i.e., faster response time to positive or negative images) depend on the congruency between spatial position/direction of swipe and hand dominance.

In literature, both the conceptual definitions and the methods used to measure financial literacy (FL) vary quite substantially. Based on OCSE definition, we refer to financial literacy not only in terms of financial knowledge, but also as skills, attitudes and behaviors that influence the financial decision-making process and, ultimately, people’s financial well-being. Hence, we developed a new tool to measure financial literacy as a multidimensional construct, specifically, our scale has four different factors: financial knowledge, assessed with an increase complexity level of items based on literature, financial self-efficacy (as the subjective perception of knowledge and competence) and financial interest (as the positive attitude towards financial topic). Finally, we also focused on the everyday financial behaviors, such as expense planning and saving. Preliminary outcomes show that the hierarchical order of the financial literacy items proved to be correct: the percentage of correct answers decreases as the items progress. Moreover, analyses reveal reliability and internal consistency for two of the three financial behavior subscales (expense planning and saving). These findings on our new scale are encouraging and highlight that financial literacy is a multidimensional construct.

Cryptocurrencies are innovative digital assets that became significantly popular in recent years. Despite their popularity, literature about cryptocurrencies is still lacking. Specifically, little is known about the psychological profiles of cryptocurrency owners. The present paper aims to investigate the role of financial literacy, self-efficacy, risk tolerance, and impulsivity in cryptocurrency ownership in a representative sample of 1,153 Italian consumers. In particular, a Latent Profile Analysis was performed on data obtained from an online survey to identify different psychological profiles (i.e., different configurations of financial literacy, self-efficacy, risk tolerance, and impulsivity levels). Results indicate the presence of six different psychological profiles and that these profiles are differently associated with the likelihood to own cryptocurrencies. Specifically, the psychological profile that best describes those who hold cryptocurrencies is characterized by high levels of financial literacy, risk tolerance, and self-efficacy in investment domains. These findings would suggest that psychological characteristics play a key role in cryptocurrency ownership.

In recent times, Italian households have faced a period of economic struggles. The financial instability and job loss might have increased the debt burden of many citizens. Thus, the purpose of the present study consisted in identifying the psychological characteristics of overindebted individuals. Specifically, a sample of 101 over-indebted individuals (F = 50.5%; Mage = 50.58, SDage 11.58= ) was compared with a control sample of 103 respondents (F = 53.4%; Mage= 51.68, SDage = 11.38) to investigate which individual differences are mainly associated with higher debt burdens. Financial literacy, Big Five personality traits, impulsivity, materialist tendencies, money attitudes and trust in institutions were assessed among the two groups. Preliminary findings showed some counterintuitive insights. Indeed, though the over-indebted sample are less likely to plan, they reported higher levels of extraversion, conscientiousness, internal locus of control and social support, whilst they also resulted less materialistic. Findings will be discussed with reference to the “scarcity paradigm”, highlighting how being in a condition of scarcity of resources may affect both cognitive and affective processing

We use femtosecond extreme ultraviolet pulses derived from a free electron laser to excite and probe surface acoustic waves (SAWs) on the (001) surface of single crystal SrTiO3. SAWs are generated by a pair of 39.9 nm pulses crossed at the sample with the crossing angle defining the SAW wavelength at 84 nm. Detection of SAWs is performed via diffraction of a time-delayed 13.3 nm probe pulse by SAW-induced surface ripples. Despite the low reflectivity of the sample in the extreme ultraviolet range, the reflection mode detection is found to be efficient because of an increase in the diffraction efficiency for shorter wavelengths. We describe a methodology for extracting the SAW attenuation in the presence of a thermal grating, which is based on measuring the decay of oscillations at twice the SAW frequency. The proposed approach can be used to study ultrahigh frequency SAWs in a broad range of materials and will bridge the wave vector gap in surface phonon spectroscopy between Brillouin scattering and He atom scattering.

We use femtosecond extreme ultraviolet pulses derived from a free electron laser to excite and probe surface acoustic waves (SAWs) on the (001) surface of single crystal SrTiO3. SAWs are generated by a pair of 39.9 nm pulses crossed at the sample with the crossing angle defining the SAW wavelength at 84 nm. Detection of SAWs is performed via diffraction of a time-delayed 13.3 nm probe pulse by SAW-induced surface ripples. Despite the low reflectivity of the sample in the extreme ultraviolet range, the reflection mode detection is found to be efficient because of an increase in the diffraction efficiency for shorter wavelengths. We describe a methodology for extracting the SAW attenuation in the presence of a thermal grating, which is based on measuring the decay of oscillations at twice the SAW frequency. The proposed approach can be used to study ultrahigh frequency SAWs in a broad range of materials and will bridge the wave vector gap in surface phonon spectroscopy between Brillouin scattering and He atom scattering.

Time-resolved transient grating (TG) spectroscopy facilitates detailed studies of electron dynamics and transport phenomena by means of a periodic excitation of matter with coherent ultrashort light pulses. Several current and next generation free-electron laser (FEL) facilities provide fully coherent pulses with few femtosecond pulse durations and extreme ultraviolet (XUV) photon energies. Thus, they allow for transient grating experiments with periodicities as small as tens of nanometers and with element specific photon energies. Here, we demonstrate the element specificity of XUV TG (X-TG) experiments by tuning the photon energy across the Si L₂,₃-edge of Si₃N₄. We observe a shortening of the signal decay when increasing the XUV photon energy above the absorption edge. The analysis of the wavelength dependent signal shows that the faster decay is driven by the increase in the charge carrier density. From the decay constants the interband Auger coefficient at elevated temperatures and high electron densities has been determined., Swiss National Science Foundation (SNF) (Grant 200021_165550/1)

Advances in developing ultrafast coherent sources operating at extreme ultraviolet (EUV) and x-ray wavelengths allow the extension of nonlinear optical techniques to shorter wavelengths. Here, we describe EUV transient grating spectroscopy, in which two crossed femtosecond EUV pulses produce spatially periodic nanoscale excitations in the sample and their dynamics is probed via diffraction of a third time-delayed EUV pulse. The use of radiation with wavelengths down to 13.3 nm allowed us to produce transient gratings with periods as short as 28 nm and observe thermal and coherent phonon dynamics in crystalline silicon and amorphous silicon nitride. This approach allows measurements of thermal transport on the ~10-nm scale, where the two samples show different heat transport regimes, and can be applied to study other phenomena showing nontrivial behaviors at the nanoscale, such as structural relaxations in complex liquids and ultrafast magnetic dynamics., United States. Department of Energy. Office of Basic Energy Sciences (Award DE-SC0001299), United States. Department of Energy. Office of Science. Energy Frontier Research Center (Award DE-SC001912)

We investigate the excitation of coherent acoustic and optical phonons by ultrashort extreme ultraviolet (EUV) pulses produced by a free electron laser. Two crossed femtosecond EUV (wavelength 12.7 nm) pulses are used to excite coherent phonons at a wavelength of 280 nm, which are detected via diffraction of an optical probe beam. Longitudinal and surface acoustic waves are measured in BK-7 glass, diamond, and Bi4Ge3O12; in the latter material, the excitation of a coherent optical phonon mode is also observed. We discuss probing different acoustic modes in reflection and transmission geometries and frequency mixing of surface and bulk acoustic waves in the signal. The use of extreme ultraviolet radiation will allow the creation of tunable GHz to THz acoustic sources in any material without the need to fabricate transducer structures., United States. Department of Energy (Award DE-FG02-00ER15087)

The rapid development of extreme ultraviolet (EUV) and x-ray ultrafast coherent light sources such as free electron lasers (FELs) has triggered the extension of wave-mixing techniques to short wavelengths. This class of experiments, based on the interaction of matter with multiple light pulses through the Nth order susceptibility, holds the promise of combining intrinsic ultrafast time resolution and background-free signal detection with nanometer spatial resolution and chemical specificity. A successful approach in this direction has been the combination of the unique characteristics of the seeded FEL FERMI with dedicated four-wave-mixing (FWM) setups, which leads to the demonstration of EUV-based transient grating (TG) spectroscopy. In this perspective paper, we discuss how the TG approach can be extended toward more general FWM spectroscopies by exploring the intrinsic multiparameter nature of nonlinear processes, which derives from the ability of controlling the properties of each field independently.