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Nowadays, as a result of the emergence of low-dimensional hybrid structures, the scientific community is interested in their interfacial carrier dynamics, including charge transfer and energy transfer. By combining the potential of transition metal dichalcogenides (TMDs) and nanocrystals (NCs) with low-dimensional extension, hybrid structures of semiconducting nanoscale matter can lead to fascinating new technological scenarios. Their characteristics make them intriguing candidates for electronic and optoelectronic devices, like transistors or photodetectors, bringing with them challenges but also opportunities. Here, we will review recent research on the combined TMD/NC hybrid system with an emphasis on two major interaction mechanisms: energy transfer and charge transfer. With a focus on the quantum well nature in these hybrid semiconductors, we will briefly highlight state-of-the-art protocols for their structure formation and discuss the interaction mechanisms of energy versus charge transfer, before concluding with a perspective section that highlights novel types of interactions between NCs and TMDs.

Doped metal oxide (MO) nanocrystals (NCs) are well-known for the localized surface plasmon resonance in the infrared range generated by free electrons in the conduction band of the material. Owing to the intimate connection between plasmonic features and the NC's carrier density profile, proper modeling can unveil the underlying electronic structure. The carrier density profile in MO NCs is characterized by the presence of an electronically depleted layer as a result of the Fermi level pinning at the surface of the NC. Moreover, the carrier profile can be spatially engineered by tuning the dopant concentrations in core-shell architectures, generating a rich plethora of plasmonic features. In this work, we systematically studied the influence of the simulation parameters used for optical modeling of representative experimental absorption spectra by implementing multilayer models. We highlight in particular the importance of minimizing the fit parameters by support of experimental results and the importance of interparameter relationships. We show that, in all cases investigated, the depletion layer is fundamental to correctly describe the continuous spectra evolution. We foresee that this multilayer model can be used to design the optoelectronic properties of core-shell systems in the framework of energy band and depletion layer engineering., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

We show how, in the synthesis of yellow-emissive Bi-doped Cs 2 Ag 1- x Na x InCl 6 double perovskite nanocrystals (NCs), preventing the transient formation of Ag 0 particles increases the photoluminescence quantum yield (PLQY) of the NCs from ∼30% to ∼60%. Calculations indicate that the presence of even a single Ag 0 species on the surface of a NC introduces deep trap states. The PL efficiency of these NCs is further increased to ∼70% by partial replacement of Na + with K + ions, up to a 7% K content, due to a lattice expansion that promotes a more favorable ligands packing on the NC surface, hence better surface passivation. A further increase in K + lowers the PLQY, due to both the activation of nonradiative quenching channels and a lower oscillator strength of the BiCl 6 →AgCl 6 transition (through which PL emission occurs). The work indicates how a deeper understanding of parameters influencing carrier trapping/relaxation can boost the PLQY of double perovskites NCs.

In this work, we observe plasmon-induced hot electron extraction in a heterojunction between indium tin oxide nanocrystals and monolayer molybdenum disulfide. We study the sample with ultrafast differential transmission, exciting the sample at 1750 nm where the intense localized plasmon surface resonance of the indium tin oxide nanocrystals is and where the monolayer molybdenum disulfide does not absorb light. With the excitation at 1750 nm, we observe the excitonic features of molybdenum disulfide in the visible range, close to the exciton of molybdenum disulfide. Such a phenomenon can be ascribed to a charge transfer between indium tin oxide nanocrystals and monolayer molybdenum disulfide upon plasmon excitation. These results are a first step toward the implementation of near-infrared plasmonic materials for photoconversion.

Bismuth telluride halides (BiTeX) are Rashba-type crystals with several potential applications ranging from spintronics and nonlinear optics to energy. Their layered structures and low cleavage energies allow their production in a two-dimensional form, opening the path to miniaturized device concepts. The possibility to exfoliate bulk BiTeX crystals in the liquid represents a useful tool to formulate a large variety of functional inks for large-scale and cost-effective device manufacturing. Nevertheless, the exfoliation of BiTeI by means of mechanical and electrochemical exfoliation proved to be challenging. In this work, we report the first ultrasonication-assisted liquid-phase exfoliation (LPE) of BiTeI crystals. By screening solvents with different surface tension and Hildebrandt parameters, we maximize the exfoliation efficiency by minimizing the Gibbs free energy of the mixture solvent/BiTeI crystal. The most effective solvents for the BiTeI exfoliation have a surface tension close to 28 mN m -1 and a Hildebrandt parameter between 19 and 25 MPa 0.5 . The morphological, structural, and chemical properties of the LPE-produced single-/few-layer BiTeI flakes (average thickness of ∼3 nm) are evaluated through microscopic and optical characterizations, confirming their crystallinity. Second-harmonic generation measurements confirm the non-centrosymmetric structure of both bulk and exfoliated materials, revealing a large nonlinear optical response of BiTeI flakes due to the presence of strong quantum confinement effects and the absence of typical phase-matching requirements encountered in bulk nonlinear crystals. We estimated a second-order nonlinearity at 0.8 eV of |χ (2) | ∼ 1 nm V -1 , which is 10 times larger than in bulk BiTeI crystals and is of the same order of magnitude as in other semiconducting monolayers (e.g., MoS 2 ).

Objectives: Fibromyalgia (FM) is a chronic musculoskeletal pain syndrome of unknown aetiopathogenesis. Its development and maintenance are related to the interplay of biological, psychological, and contextual factors. Among the contextual factors, sociodemographic aspects are poorly elucidated. This study aimed to evaluate the relationships between sociodemographic/clinical factors and symptom severity measures using a web-based registry of patients with FM., Methods: Adult patients with an ACR 2010/2011 diagnosis of FM underwent a clinical evaluation and were asked to complete questionnaires covering their sociodemographic data (gender, age, marital status, educational level), and disease-specific measures (the revised Fibromyalgia Impact Questionnaire (FIQR), and the Polysymptomatic Distress Scale (PDS))., Results: Data relating to 3,221 patients (3001 women and 220 men) was collected. The ANOVA showed significant difference in mean FIQR scores when the five marital conditions (cohabiter, married, separated/divorced, single, widowed) were compared (F 3.321, p<0.01). While males and females were found to have comparable FIQR scores, the interaction between gender and marital status indicated that separated/divorced males have higher FIQR scores (F 5.684, p=0.001). The multiple regression analysis demonstrated that patients who reported lower educational level experienced more severe FM symptoms, as scored with FIQR (p<0.0001)., Conclusions: Our results indicated that being male and separated/divorced is associated to higher severity of FM symptoms, as rated with FIQR. Furthermore, a relationship between educational level and FIQR scores has been detected. This study supports the importance of collecting simple SES measures to identify environmental risk factors for FM severity.

Objectives: The role of age in influencing the severity of fibromyalgia (FM) is still controversial. The aim of this study is to define the contribution of age in the severity of FM from data from a large national database., Methods: This cross-sectional study included adult patients with FM diagnosed according to the 2010/2011 American College of Rheumatology criteria. Disease severity was assessed with the revised Fibromyalgia Impact Questionnaire (FIQR) and the modified Fibromyalgia Assessment Status (FAS 2019mod). Patients were grouped into five age categories (between 18-40 years, between 41-50 years, between 51-60 years, between 61-70 years, and ≥71 years). Differences in disease severity between groups were assessed by one-way analysis of variance (ANOVA)., Results: The study included 2889 patients (199 males and 2690 females), mean age of 52.58 (±11.82) years, with a mean FIQR score of 59.22 (±22.98) and a mean FAS 2019mod of 25.50 (±8.66). Comparing the mean values of the various indices between age categories, there were no statistically significant differences between the groups for FIQR total score and FAS 2019mod. However, the 60-70 years category showed the lowest scores for both scales. The main difference emerged for the FIQR physical function subscale, where the ≥71 years category showed significantly higher scores (p<0.05) compared the 18-40 years category., Conclusions: The severity of FM has a significant level of stationarity according to age categories. Patients between 60-70 years have a lower disease burden. Physical function is the health domain with the most significant difference between the groups.

Fermi level pinning in doped metal oxide (MO) nanocrystals (NCs) results in the formation of depletion layers, which affect their optical and electronic properties, and ultimately their application in smart optoelectronics, photocatalysis, or energy storage. For a precise control over functionality, it is important to understand and control their electronic bands at the nanoscale. Here, we show that depletion layer engineering allows designing the energetic band profiles and predicting the optoelectronic properties of MO NCs. This is achieved by shell thickness tuning of core-shell Sn:In 2 O 3 -In 2 O 3 NCs, resulting in multiple band bending and multi-modal plasmonic response. We identify the modification of the band profiles after the light-induced accumulation of extra electrons as the main mechanism of photodoping and enhance the charge storage capability up to hundreds of electrons per NC through depletion layer engineering. Our experimental results are supported by theoretical models and are transferable to other core-multishell systems as well., (© 2022. The Author(s).)

Metal oxide nanocrystals are emerging as an extremely versatile material for addressing many of the current challenging demands of energy-conversion technology. Being able to exploit their full potential is not only an advantage but also a scientific and economic ambition for a more sustainable energy development. In this direction, the photodoping of metal oxide nanocrystals is a very notable process that allows accumulating multiple charge carriers per nanocrystal after light absorption. The reactivity of the photodoped electrons is currently the subject of an intense study. In this context, the possibility to extract efficiently the stored electrons could be beneficial for numerous processes, from photoconversion and sunlight energy storage to photocatalysis and photoelectrochemistry. In this work we provide, via oxidative titration and optical spectroscopy, evidence for multi-electron transfer processes from photodoped Sn : In 2 O 3 nanocrystals to a widely employed organic electron acceptor (F4TCNQ). The results of this study disclose the potential of photodoped electrons to drive chemical reactions involving more than one electron., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The growing demand for self-powered devices has led to the study of novel energy storage solutions that exploit green energies whilst ensuring self-sufficiency. In this context, doped metal oxide nanocrystals (MO NCs) are interesting nanosized candidates with the potential to unify solar energy conversion and storage into one set of materials. In this review, we aim to present recent and important developments of doped MO NCs for light-driven multi-charge accumulation (i.e., photodoping) and solar energy storage. We will discuss the general concept of photodoping, the spectroscopic and theoretical tools to determine the charging process, together with unresolved open questions. We conclude the review by highlighting possible device architectures based on doped MO NCs that are expected to considerably impact the field of energy storage by combining in a unique way the conversion and storage of solar power and opening the path towards competitive and novel light-driven energy storage solutions.

Objective: Various studies have shown that overweight and obesity are central features of FM, but the real impact of a high BMI on clinical severity in patients with FM is still controversial. The aim of this study was to analyse the relationships between BMI categories and measures of symptom severity and functional impairment using data from a Web-based registry of patients with FM., Methods: Adult patients with an ACR 2010/2011 diagnosis of FM underwent a complete physical examination and laboratory tests and were asked to complete a package of questionnaires covering their sociodemographic and treatment details, in addition to the following disease-specific questionnaires: the revised Fibromyalgia Impact Questionnaire (FIQR), the modified Fibromyalgia Assessment Status questionnaire (ModFAS) and the Polysymptomatic Distress Scale (PDS)., Results: A total of 2339 patients were recruited and divided into two weight categories, underweight/normal (U/N, n  = 1127, 48.2%) and overweight/obese (O/O, n  = 1212, 51.8%). The total and subscales of FIQR, ModFAS and PSD scores were significantly higher in the O/O patients, as were all the mean scores of the individual FIQR items ( P  < 0.001 for all)., Conclusion: Our findings demonstrate that O/O patients with FM are significantly more impaired than U/N patients in all the symptomatological and functional domains as measured using the FIQR, ModFAS and PDS, thus suggesting that being O/O has an additional effect on symptoms and function., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Society for Rheumatology.)

Objective: To establish optimal cut-off values for the scores of the revised Fibromyalgia Impact Questionnaire (FIQR), the modified Fibromialgia Assessment Scale (FAS 2019mod), and the Polysymptomatic Distress Scale (PDS) in order to distinguish five levels of FM disease severity., Methods: Consecutive FM patients were evaluated with the three clinimetric indices, and each patient was required to answer the anchor question: 'In general, would you say your health is 1 = very good, 2 = good, 3 = fair, 4 = poor, or 5 = very poor?'-which represented the external criterion. Cut-off points were established through the interquartile reconciliation approach., Results: The study sample consisted of 2181 women (93.2%) and 158 men (6.8%), with a mean age of 51.9 (11.5) years, and mean disease duration was 7.3 (6.9) years. The overall median FIQR, FAS 2019 mod and PDS scores (25th-75th percentiles) were respectively 61.16 (41.16-77.00), 27.00 (19.00-32.00) and 19.0 (13.00-24.00). Reconciliation of the mean 75th and 25th percentiles of adjacent categories defined the severity states for FIQR: 0-23 for remission, 24-40 for mild disease, 41-63 for moderate disease, 64-82 for severe disease and >83 for very severe disease; FAS 2019 mod: 0-12 for remission, 13-20 for mild disease, 21-28 for moderate disease, 29-33 for severe disease and >33 for very severe disease; PDS: 0-5 for remission, 6-15 for mild disease, 16-20 for moderate disease, 21-25 for severe disease and >25 for very severe disease., Conclusions: Disease severity cut-offs can represent an important improvement in interpreting FM., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Understanding and tuning the ligand shell composition in colloidal halide perovskite nanocrystals (NCs) has been done systematically only for Pb-based perovskites, while much less is known on the surface of Pb-free perovskite systems. Here, we reveal the ligand shell architecture of Bi-doped Cs 2 Ag 1- x Na x InCl 6 NCs via nuclear magnetic resonance analysis. This material, in its bulk form, was found to have a photoluminescence quantum yield (PLQY) as high as 86%, a record value for halide double perovskites. Our results show that both amines and carboxylic acids are present and homogeneously distributed over the surface of the NCs. Notably, even for an optimized surface ligand coating, achieved by combining dodecanoic acid and decylamine, a maximum PLQY value of only 37% is reached, with no further improvements observed when exploiting post-synthesis ligand exchange procedures (involving Cs-oleate, different ammonium halides, thiocyanates and sulfonic acids). Our density functional theory calculations indicate that, even with the best ligands combination, a small fraction of unpassivated surface sites, namely undercoordinated Cl ions, is sufficient to create deep trap states, opposite to the case of Pb-based perovskites that exhibit much higher defect tolerance. This was corroborated by our transient absorption measurements, which showed that an ultrafast trapping of holes (most likely mediated by surface Cl-trap states) competes with their localization at the AgCl 6 octahedra, from where, instead, they can undergo an optically active recombination yielding the observed PL emission. Our results highlight that alternative surface passivation strategies should be devised to further optimize the PLQY of double perovskite NCs, which might include their incorporation inside inorganic shells., Competing Interests: The authors declare no competing financial interest.

Objective: Striking evidence of HCV infection has been found in mixed cryoglobulinemia (MC) and HCV has been hypothesized to be the causative agent of this disease. To assess the association of C virus infection and cryoglobulinemia we studied cryoglobulin levels in 66 patients on maintenance hemodyalisis who were selected on the basis of HCVAb positivity and not because they were affected by liver disease. The control group was made up of 45 patients also on hemodyalisis but without HCV infection., Results: Circulating cryoglobulins were found in 34 (52%) of 66 HCV+ patients: the cryocrit was < 1% in 20, 1 to 5% in 12, and > 5% in 2 patients. The cryoglobulins were classified by immunofixation as type II in 8 and type III in 8 others; identification was not possible in 18 cases. In the HCVAb- control group untypable cryoglobulins were detected in 9% of the patients at < 1% by volume. No correlation was found between these data and the liver disease detected by biohumoral tests., Conclusions: Our data confirm the close link between HCV infection and cryoglobulins; the prevalence of circulating cryoglobulins in uremic HCVAb+ patients is very close to that found in HCV-related liver disease.

Objective: To determine the prevalence of antibodies against HCV in monoclonal gammopathies with and without cryoglobulinemic activity., Methods: 201 patients were divided into two groups: (I) 94 patients with monoclonal gammopathies with cryoglobulinemic activity, and (II) 107 with monoclonal gammopathies without cryoglobulinemic activity. Cryoglobulins were characterized by immunofixation; HCVAb were detected using second-generation ELISA and RIBA methods; in 38 cases the presence of HCV in peripheral blood mononuclear cells was evaluated by PCR., Results: The HCVAb prevalence, as evaluated by RIBA, in Group I was 69.1% while in Group II it was only 14.9%. Histological and immunohistochemical study of the bone marrow in Group I patients frequently showed signs of nodular B-cell clonal expansion., Conclusions: Our data confirm the existence of a close correlation between HCV infection and the monoclonal gammopathies with cryoglobulinemic activity. HCV-positive cryoglobulinemic is characterized by self-limiting IgM monoclonal expansion associated with histological aspects of bone marrow lymphoid nodules that do not expand in the course of the disease like classic evolving lymphoproliferative processes.

Objective: The experience of our group in the characterization of the cryoglobulins during the last 8 years is reported, and the possible advantages of immunofixation versus immunoblotting are discussed., Methods: 25 out of 171 cryoprecipitates studied by immunofixation were also examined by immunoblotting, a technique which has been suggested to offer advantages in analysing monoclonal components., Results: We confirm that immunofixation may be the technique of choice given its easier execution and interpretation, better standardization, and lower overall cost.