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The last decade has witnessed the advance of metal halide perovskites as a promising low-cost and efficient class of light harvesters used in solar cells (SCs). Remarkably, the efficiency of lab-scale perovskite solar cells (PSCs) reached a power conversion efficiency of 25.5% in just ~10 years of research, rivalling the current record of 26.1% for Si-based PVs. To further boost the performances of PSCs, the use of 2D materials (such as graphene, transition metal dichalcogenides and transition metal carbides, nitrides and carbonitrides) has been proposed, thanks to their remarkable optoelectronic properties (that can be tuned with proper chemical composition engineering) and chemical stability. In particular, 2D materials have been demonstrated as promising candidates for (i) accelerating hot carrier transfer across the interfaces between the perovskite and the charge extraction layers; (ii) improving the crystallization of the perovskite layers (when used as additives in the precursor solution); (iii) favoring electronic bands alignment through tuning of the work function. In this mini-review, we discuss the physical mechanisms underlying the increased efficiency of 2D material-based PSCs, focusing on the three aforementioned effects.

Anthropogenic microparticles (AMs) were found for the first time in specimens of Trematomus bernacchii collected in 1998 in the Ross Sea (Antarctica) and stored in the Antarctic Environmental Specimen Bank. Most of the identified AMs were fibers of natural and synthetic origin. The natural AMs were cellulosic, the synthetic ones were polyester, polypropylene, polypropylene/polyester, and cellulose acetate. The presence of dyes in the natural AMs indicates their anthropogenic origin. Five industrial dyes were identified by Raman spectroscopy with Indigo occurring in most of them (55%). Our research not only adds further data to the ongoing knowledge of pollution levels in the Antarctic ecosystem, it provides an interesting snapshot of the past, highlighting that microplastics and anthropogenic fiber pollution had already entered the Antarctic marine food web at the end of the ‘90 s. These findings therefore establish the foundations for understand the changes in marine litter pollution over time.

Lipid rafts are dynamic microdomains in the membrane, rich in cholesterol and sphingolipids, that are critical for biological processes like cell signalling, membrane trafficking, and protein organization. Their essential role is claimed in both physiological and pathological conditions, including cancer, neurodegenerative diseases, and viral infections, making them a key area of research. Fluorescence-based approaches, including super-resolution fluorescence microscopy techniques, enable precise analysis of the organization, dynamics, and interactions of these microdomains, thanks also to the innovative design of appropriate fluorescent probes. Moreover, these non-invasive approaches allow for the study of live cells, facilitating the collection of quantitative data under physiologically relevant conditions. This review synthesizes the latest insights into the role of lipid rafts in biological and pathological processes and underscores how fluorescence techniques have advanced our understanding of these critical microdomains. The findings emphasize the pivotal role of lipid rafts in health and disease, providing a foundation for future research and potential therapeutic interventions.

Binge drinking (BD) is a common pattern of alcohol consumption among adolescents. At present few data are available on the possible relationship between BD and alcohol use disorders (AUD) in adolescents. The aim of this study was to assess the prevalence of BD and relationship between BD behavior and AUD among adolescents. A total of 2704 students attending 10 purposively selected high schools from three Italian provinces were surveyed. Questionnaires regarding socio-demographic data, pattern and amount of alcohol intake, smoking habits, use of illicit drugs, and physical activity were administered. AUD and affective disorders were also evaluated. Alcohol intake was reported by 2126 participants; 1278 reported at least one episode BD in the last year and 715 in the last month. A diagnosis of AUD was made in 165 adolescents. The prevalence of AUD was higher in adolescents that reported BD behavior than in those that did not report BD (11.6% vs 0.9%, respectively; p < 0.0001). Logistic regression showed a positive relationship between a diagnosis of AUD and BD behavior (OR 9.6; 95% CI 4.7–22·9; p < 0.0001). In conclusion alcohol consumption with the pattern of BD among adolescents is highly related to development of AUD.

The one-pot synthesis of N-doped graphene quantum dots (GQDs), capped with a positively charged polyamine (trien), has been realized through a microwave-assisted pyrolysis on solid L-glutamic acid and trien in equimolar amounts. The resulting positively charged nanoparticles are strongly emissive in aqueous solutions and are stable for months. The interaction with the anionic tetrakis(4-sulphonatophenyl)porphyrin (TPPS4) has been investigated at neutral and mild acidic pH using a combination of UV/vis absorption spectroscopy together with static and time-resolved fluorescence emission. At pH = 7, the experimental evidence points to the formation of a supramolecular adduct mainly stabilized by electrostatic interactions. The fluorescence emission of the porphyrin is substantially quenched while GQDs remain still emissive. On decreasing the pH, protonation of TPPS4 leads to formation of porphyrin J-aggregates through the intermediacy of the charged quantum dots.

Water in membrane interphases is vital for cellular biological functions, but despite its importance, the structure and function of biological water remain elusive. Here, by studying the OH stretching mode in partially hydrated lipid multilayers by FTIR measurements, relevant information on the water structure near the surface with lipid membranes has been gathered. The water hydrogen bond network is highly perturbed in the first layers that are in contact with the lipid membrane, exhibiting strong deviations from tetrahedral symmetry and a significant number of defects, such as isolated water molecules and a large number of hydrogen-bonded water dimers in the interphase region. These findings support the hypothesis that water chains form in phospholipid membranes, and are involved in the proton transfer across lipid bilayers by phosphate groups of opposing lipids. Furthermore, we have determined that even at very low hydration levels, a small amount of water is embedded within the confined spaces of the hydrocarbon region of phospholipid bilayers, which could potentially contribute to the structural stability of the lipid membrane.

Flexible energy storage devices and supercapacitors in particular have become very attractive due to the growing demand for wearable consumer devices. To obtain supercapacitors with improved performance, it is useful to resort to hybrid electrodes, usually nanocomposites, that combine the excellent charge transport properties and high surface area of nanostructured carbon with the electrochemical activity of suitable metal oxides or conjugated polymers. In this work, electrochemically active conducting inks are developed starting from commercially available polypyrrole and graphene nanoplatelets blended with dodecylbenzenesulfonic acid. Films prepared by applying the developed inks are characterized by means of Raman measurements, Fourier Transform Infrared (FTIR) analysis, and Atomic Force Microscopy (AFM) investigations. Planar supercapacitor prototypes with an active area below ten mm2 are then prepared by applying the inks onto transparency sheets, separated by an ion-permeable nafion layer impregnated with lithium hexafluorophospate, and characterized by means of electrical measurements. According to the experimental results, the devices show both pseudocapacitive and electric double layer behavior, resulting in areal capacitance that, when obtained from about 100 mF⋅cm−2 in the sample with polypyrrole-based electrodes, increases by a factor of about 3 when using electrodes deposited from inks containing polypyrrole and graphene nanoplateles.

Since the beginning of intensive studies on graphene and graphitic materials, Raman spectroscopy has always been used as a characterisation technique. This is due to two main reasons: the non-destructive nature of this experimental technique and its ability to distinguish between the plethora of existing carbon materials. One of the most challenging research activities concerns the production of graphene microcircuits. To address this issue, a possible strategy is to directly reduce and pattern graphite oxide (GO) film by laser irradiation. The objective of this study is to evaluate the laser irradiation-induced structural changes on thin GO films by using Micro-Raman spectroscopy. We used as a source a Nd:YAG laser (1064 nm) and different laser fluences: 15 J/cm 2 , 7.5 J/cm 2 and 5 J/cm 2 . We have analyzed the modifications of the main Raman contributions of these graphitic materials: the D band (defect induced band), the G band (band due to sp 2 hybridized carbon atoms) and the 2D band (D band overtone). In particular, we found out that our figure of merit (FOM) parameters, i.e. the intensity ratio I D /I G (for the D band and G band) and I 2D /I G (for the 2D band and G band), change with the laser fluences, revealing a different effect induced by the laser irradiation. The best results are found in the sample irradiated with 5 J/cm 2 , suggesting that higher fluences do not lead to better results.

The vibrational signature in the far-infrared region of two different phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), was investigated as a function of relative humidity from 0 to 75% in order to evaluate the effect of headgroup composition on the formation of intermolecular interactions. The substructures of the frequency region between 50 and 300 cm−1 were identified, and changes in the frequency and intensity of the related vibrations with hydration were analyzed. Interestingly, in PE, two additional vibrational bands with respect to PC were found at 162 and 236 cm−1 and assigned to intermolecular hydrogen bonds between the hydrogen-bond-donating groups, -NH3+, and hydrogen-bond-accepting groups, —P—O− and —COO, of adjacent molecules. The presence of these interactions also affected the penetration of water, severely reducing the hydration capability of PE lipids.

PurposeDifferent devices have been used for the diagnosis of obstructive sleep apnea (OSA), which differ in the number of sensors used. The numerous sensors used in more complex sleep studies such as in-lab polysomnography may influence body position during sleep. We hypothesized that patients submitted to in-lab polysomnography (PSG) would spend more time in the supine position than patients submitted to an ambulatory Portable Monitor (PM) sleep study.MethodsBody position during PSG and PM studies was compared among two distinct groups of patients matched for age, body-mass index (BMI), apnea–hypopnea index (AHI), and gender. Predictors of time spent in the supine position were determined using a multiple linear regression model.ResultsOf 478 participants who underwent either PSG or PM studies, mean age: 61[43–66] years; males: 43.9%; BMI: 28.4[26.1–31.1]kg/m2; AHI 14[7–27] events/hour). Participants who underwent PSG studies spent more time in the supine position (41[16–68]% than participants who underwent PM studies (34[16–51]%), P = 0.014. Participants with OSA spent more time in the supine position than participants without OSA, both among the PSG and PM groups P < 0.05). Gender, BMI, OSA severity, and sleep study type were independent predictors of time spent in the supine position.ConclusionIn-lab PSG may increase time spent in the supine position and overestimate OSA severity compared to a PM sleep study. OSA diagnosis is also associated with increased time spent in the supine position. The potential influence on the sleeping position should be taken into account when choosing among the different sleep study types for OSA diagnosis.