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The efficient detection of ionizing radiation is crucial in various tools developed for X-ray-based security, particle identification, and medical diagnostics. Intensive research is underway to enhance the performance of current detectors, focusing on improving sensitivity, and timing response. In the well-known garnet single crystal family, new complex compositions are emerging, with Gd3(Ga,Al)5O12 (GGAG) recently gaining attention due to its high light yield of over 104 photons/MeV and short scintillation lifetime of a few tens of ns when doped with Cerium. Nevertheless, the challenges associated with producing bulk crystals have prompted a search for alternative and more manageable materials. In this context, advancements in sintering techniques for transforming crystalline micro-grains into bulk ceramics with high optical quality have enabled optical ceramics to become highly competitive compared to single crystals. This is due to the relative ease of production, the ability to uniformly incorporate high concentrations of activators, and the versatility of shaping that allows for complex geometries in a single piece without requiring mechanical post-processing or bonding. Our recent research efforts have resulted in the development of fully densified Ce:GGAG optical ceramics through reaction sintering using commercial oxide powders [1]. We optimized the synthesis process to eliminate porosity and achieve good optical quality by employing a combined approach involving pressureless sintering in air followed by hot isostatic pressing, along with the use of sintering aids. Furthermore, directional sensitivity is a crucial requirement for detectors used in locating orphan nuclear sources. To address this, we also explore unconventional geometries by combining two layers of different garnets (Ce:GGAG and Pr:YAG), revealing a scintillation response strongly influenced by the material architecture, extending the potential of layered optical ceramics for energy- and dire

Information on patterns of prescription of long-acting injection (LAI) antipsychotics among people who are incarcerated is lacking. Therefore, we aimed to evaluate prescribing rates for first-generation antipsychotic (FGA)-LAI versus second-generation antipsychotic (SGA)-LAI and to identify the factors associated with the prescription of one of the two classes of LAI. A cross-sectional study was conducted among incarcerated adult males hosted in Monza detention center between January 2013 and April 2023. Socio-demographic and clinical data were retrospectively collected. Descriptive and univariate statistics as well as logistic regression analyses were performed. Data were available for 135 consecutive incarcerated adult males with different mental disorders who received a LAI as part of their treatment. 75.6% of our sample was treated with FGA-LAIs, with haloperidol as the most commonly prescribed drug, followed by zuclopentixol and aripiprazole. Diagnosis of bipolar disorder and concomitant administration of antidepressants were statistically significant predictors of SGA-LAI prescription. Some patients' characteristics may influence prescription patterns in prison. Further longitudinal studies with larger samples should confirm these findings.

Although risk factors for recidivism were extensively studied, re-incarcerations still account for a disproportionate amount of overall service use and cost. Therefore, the main objectives of the study were (1) to estimate the prevalence of re-incarcerations in a sample of male incarcerated people and (2) to verify if some socio-demographic and clinical features including impulsivity can be risk factors of re-incarceration. We conducted a cross-sectional study recruiting 479 newly arrived incarcerated people in an Italian detention centre, between 2018 and 2022. The incarcerated individuals were interviewed to collect clinical information. Impulsivity was assessed by the Barratt Impulsiveness Scale (BIS-11). A total of 479 consecutive male incarcerated people was included. Two hundred and seventy-six of them (57.6%) had previously been incarcerated. Logistic regression analysis showed that having higher age, to be married or in relationship, to have low-medium level of education, housing instability, low or no income, cocaine use disorder in the last year and a history of non-suicidal self-injuries increased the likelihood of recurrent incarcerations. Moreover, re-incarceration was associated with higher rate of personality disorders and higher scores on attentional and motor impulsivity. Reintegration programs should address some risk factors associated with re-incarceration and promote social rehabilitation among incarcerated individuals.

Lead halide perovskite nanocrystals (LHP-NCs) embedded in polymeric hosts are gaining attention as scalable and low-cost scintillation detectors for technologically relevant applications. Despite rapid progress, little is currently known about the scintillation properties and stability of LHP-NCs prepared by the ligand assisted reprecipitation (LARP) method, which allows mass scalability at room temperature unmatched by any other type of nanostructure, and the implications of incorporating LHP-NCs into polyacrylate hosts are still largely debated. Here, we show that LARP-synthesized CsPbBr3 NCs are comparable to particles from hot-injection routes and unravel the dual effect of polyacrylate incorporation, where the partial degradation of LHP-NCs luminescence is counterbalanced by the passivation of electron-poor defects by the host acrylic groups. Experiments on NCs with tailored surface defects show that the balance between such antithetical effects of polymer embedding is determined by the surface defect density of the NCs and provide guidelines for further material optimization.

In recent years, the field of radiation detection has witnessed a paradigm shift with the emergence of plastic scintillators incorporating perovskite nanocrystals (PNCs). This innovative class of scintillators not only capitalizes on the superior luminescent properties of PNCs but also harnesses the flexibility and processability of polymers. This review explores the intricate landscape of synthesizing and fabricating scintillating PNCs and nanocomposites, delving into the methods employed in their production. From solution-based methods to innovative solid-state approaches, the synthesis of PNCs for scintillators application is explored comprehensively. Furthermore, embedding strategies within polymeric matrices are scrutinized, shedding light on the various techniques utilized to achieve optimal dispersion and compatibility. The evaluation of the final nanocomposites is finally discussed, with a particular emphasis on their scintillating performance and radiation hardness. Through a meticulous exploration of synthesis methodologies, embedding techniques, and performance assessments, this Review aims to provide a multilayered understanding of the state-of-the-art in PNC-based nanoscintillators

Lead halide perovskite nanocrystals (LHP-NCs) embedded in polymeric hosts are gaining attention as scalable and low-cost scintillation detectors for technologically relevant applications. Despite rapid progress, little is currently known about the scintillation properties and stability of LHP-NCs prepared by the ligand assisted reprecipitation (LARP) method, which allows mass scalability at room temperature unmatched by any other type of nanostructure, and the implications of incorporating LHP-NCs into polyacrylate hosts are still largely debated. Here, we show that LARP-synthesized CsPbBr3 NCs are comparable to particles from hot-injection routes and unravel the dual effect of polyacrylate incorporation, where the partial degradation of LHP-NCs luminescence is counterbalanced by the passivation of electron-poor defects by the host acrylic groups. Experiments on NCs with tailored surface defects show that the balance between such antithetical effects of polymer embedding is determined by the surface defect density of the NCs and provide guidelines for further material optimization.

The use of scintillators for the detection of ionizing radiation is a critical aspect in many fields, including medicine, nuclear monitoring, and homeland security. Recently, lead halide perovskite nanocrystals (LHP-NCs) have emerged as promising scintillator materials. However, the difficulty of affordably upscaling synthesis to the multigram level and embedding NCs in optical-grade nanocomposites without compromising their optical properties still limits their widespread use. In addition, fundamental aspects of the scintillation mechanisms are not fully understood, leaving the scientific community without suitable fabrication protocols and rational guidelines for the full exploitation of their potential. In this work, we realize large polyacrylate nanocomposite scintillators based on CsPbBr3 NCs, which are synthesized via a novel room temperature, low waste turbo-emulsification approach, followed by their in situ transformation during the mass polymerization process. The interaction between NCs and polymer chains strengthens the scintillator structure, homogenizes the particle size distribution and passivates NC defects, resulting in nanocomposite prototypes with luminescence efficiency >90%, exceptional radiation hardness, 4800 ph/MeV scintillation yield even at low NC loading, and ultrafast response time, with over 30% of scintillation occurring in the first 80 ps, promising for fast-time applications in precision medicine and high-energy physics. Ultrafast radioluminescence and optical spectroscopy experiments using pulsed synchrotron light further disambiguate the origin of the scintillation kinetics as the result of charged-exciton and multiexciton recombination formed under ionizing excitation. This highlights the role of nonradiative Auger decay, whose potential impact on fast timing applications we anticipate via a kinetic model.

The 16th International Conference on Inorganic Scintillators and their Applications (SCINT 2022) was organized by the Los Alamos National Laboratory, and held in Santa Fe, NM, USA, from September 19 to October 23, 2022. More than 200 colleagues from nearly 20 different countries finally participated in the conference. The program consisted of five invited and ten keynote lectures, and 74 oral and 46 poster contributions. A special memorial session was devoted to Prof. Richard T. Williams. Extended exhibition with altogether about ten exhibitor stands provided another link to the market applications behind the research. An intense and structured research and development in the field of scintillators was represented by 15 sessions oriented toward various material technologies including nanomaterials, metamaterials, and classical bulk single crystals and optical ceramics. Their characterization, modeling, and underlying physical mechanisms description constituted the subject of a major part of conference contributions. Finally, various applications of inorganic scintillators were presented and discussed.

We report a study of composite scintillating ceramics based on coupled layers of two different garnets, namely Ce-doped gadolinium gallium aluminium (GGAG:Ce) and Pr-doped yttrium aluminium (YAG:Pr), fabricated by hot isostatic pressing. Two samples were prepared, with different GGAG:Ce layer thickness, 120 µm and 690 µm respectively, but with a comparable overall thickness of 1.4 mm. The key finding is that the material architecture strongly determines the scintillation response. The radioluminescence is that expected from the irradiated material when a thick layer of ceramic is exposed to X-rays. Conversely, exposing a thin layer allows a non-null probability —about 0.3% for 120 µm of GGAG— of finding an X-ray photon in the underlying layer, and thus radioluminescence from both materials is recorded. We believe these results can extend the potential of layered optical ceramics for advanced devices, such as energy- and direction-sensitive X-ray detectors.

The use of scintillators for the detection of ionizing radiation is a critical aspect in many fields, including medicine, nuclear monitoring, and homeland security. Recently, lead halide perovskite nanocrystals (LHP-NCs) have emerged as promising scintillator materials. However, the difficulty of affordably upscaling synthesis to the multigram level and embedding NCs in optical-grade nanocomposites without compromising their optical properties still limits their widespread use. In addition, fundamental aspects of the scintillation mechanisms are not fully understood, leaving the scientific community without suitable fabrication protocols and rational guidelines for the full exploitation of their potential. In this work, we realize large polyacrylate nanocomposite scintillators based on CsPbBr3 NCs, which are synthesized via a novel room temperature, low waste turbo-emulsification approach, followed by their in situ transformation during the mass polymerization process. The interaction between NCs and polymer chains strengthens the scintillator structure, homogenizes the particle size distribution and passivates NC defects, resulting in nanocomposite prototypes with luminescence efficiency >90%, exceptional radiation hardness, 4800 ph/MeV scintillation yield even at low NC loading, and ultrafast response time, with over 30% of scintillation occurring in the first 80 ps, promising for fast-time applications in precision medicine and high-energy physics. Ultrafast radioluminescence and optical spectroscopy experiments using pulsed synchrotron light further disambiguate the origin of the scintillation kinetics as the result of charged-exciton and multiexciton recombination formed under ionizing excitation. This highlights the role of nonradiative Auger decay, whose potential impact on fast timing applications we anticipate via a kinetic model.

The search for efficient, re-absorption-free scintillators has recently focused the attention on antimony-based halides, which exhibit largely Stokes shifted luminescence due to radiative recombination of excitons self-trapped (STE) in strongly Jahn–Teller distorted Sb3+ color centers. Here, the synthesis of a hybrid structure is reported with chemical formula (C13H14N3)3SbCl6 consisting of spatially isolated [SbCl6]3− octahedra separated by organic N,N'-diphenylguanidinium (Gua) molecules. The optical properties of this material are mainly determined by the inorganic component and are characterized by a pronounced Stokes shift of ≈1.3 eV and a room-temperature photoluminescence (PL) efficiency of up to 85%. Remarkably, highly efficient radioluminescence (RL) is observed with scintillation light yields of ≈2000 ph MeV−1 using both soft X-rays and a 124 keV gamma source. Temperature-dependent PL and RL measurements confirm the minor role of non-radiative channels, which are completely suppressed below 100 K. Thermally stimulated luminescence measurements suggest that the traps in Gua3SbCl6 crystals have a significantly large energy depth distribution below the absorbing state.

Natural and anthropogenic gas radionuclides such as radon, xenon, hydrogen and krypton isotopes must be monitored to be managed as pathogenic agents, radioactive diagnostic agents or nuclear activity indicators. State-of-the-art detectors based on liquid scintillators suffer from laborious preparation and limited solubility for gases, which affect the accuracy of the measurements. The actual challenge is to find solid scintillating materials simultaneously capable of concentrating radioactive gases and efficiently producing visible light revealed with high sensitivity. The high porosity, combined with the use of scintillating building blocks in metal–organic frameworks (MOFs), offers the possibility to satisfy these requisites. We demonstrate the capability of a hafnium-based MOF incorporating dicarboxy-9,10-diphenylanthracene as a scintillating conjugated ligand to detect gas radionuclides. Metal–organic frameworks show fast scintillation, a fluorescence yield of ∼40%, and accessible porosity suitable for hosting noble gas atoms and ions. Adsorption and detection of 85Kr, 222Rn and 3H radionuclides are explored through a newly developed device that is based on a time coincidence technique. Metal–organic framework crystalline powder demonstrated an improved sensitivity, showing a linear response down to a radioactivity value below 1 kBq m−3 for 85Kr, which outperforms commercial devices. These results support the possible use of scintillating porous MOFs to fabricate sensitive detectors of natural and anthropogenic radionuclides.

Multicomponent nanomaterials consisting of dense scintillating particles functionalized by or embedding optically active conjugated photosensitizers (PSs) for cytotoxic reactive oxygen species (ROS) have been proposed in the last decade as coadjuvant agents for radiotherapy of cancer. They have been designed to make scintillation-activated sensitizers for ROS production in an aqueous environment under exposure to ionizing radiations. However, a detailed understanding of the global energy partitioning process occurring during the scintillation is still missing, in particular regarding the role of the non-radiative energy transfer between the nanoscintillator and the conjugated moieties which is usually considered crucial for the activation of PSs and therefore pivotal to enhance the therapeutic effect. We investigate this mechanism in a series of PS-functionalized scintillating nanotubes where the non-radiative energy transfer yield has been tuned by control of the intermolecular distance between the nanotube and the conjugated system. The obtained results indicate that non-radiative energy transfer has a negligible effect on the ROS sensitization efficiency, thus opening the way to the development of different architectures for breakthrough radiotherapy coadjutants to be tested in clinics.

Multicomponent systems consisting of lead halide perovskite nanocrystals (CsPbX3-NCs, X = Br, I) grown inside mesoporous silica nanospheres (NSs) with selectively sealed pores combine intense scintillation and strong interaction with ionizing radiation of CsPbX3 NCs with the chemical robustness in aqueous environment of silica particles, offering potentially promising candidates for enhanced radiotherapy and radio-imaging strategies. We demonstrate that CsPbX3 NCs boost the generation of singlet oxygen species (1O2) in water under X-ray irradiation and that the encapsulation into sealed SiO2 NSs guarantees perfect preservation of the inner NCs after prolonged storage in harsh conditions. We find that the 1O2 production is triggered by the electromagnetic shower released by the CsPbX3 NCs with a striking correlation with the halide composition (I3 > I3-xBrx > Br3). This opens the possibility of designing multifunctional radio-sensitizers able to reduce the local delivered dose and the undesired collateral effects in the surrounding healthy tissues by improving a localized cytotoxic effect of therapeutic treatments and concomitantly enabling optical diagnostics by radio imaging.

The precise spatial assembly of chromophores inside MOF allows for the rational fabrication of photonic materials with unique photophysical properties. We propose an innovative radioactive gas detector based on highly porous luminescent MOFs.[1] Hf-based MOFs containing diphenyl anthracene (DPA) moieties display high porosity (SBET = 2550 m2 g-1), fast and reversible adsorption of noble gases (proven by combined experimental adsorption and simulation methods) and high photoluminescence and scintillating properties. After exposure to radioactive gases, Hf-DPA displays fast and bright scintillation sensitized by the decay of the radioactive nuclei that allows for their effective detection at ultra-low concentrations. Indeed, 85Kr isotope was detected even at activity as low as 0.3 kBq⋅m3, below the minimum value declared for commercial devices, strongly supporting the development of MOFbased scintillators for radioactive gas detection. Fast composite scintillators were engineered by embedding nanocrystalline Zr-MOFs containing highly luminescent DPA moieties in a continuous polymer matrix.[2] The hybrid bulk scintillators display good light yield, fast time response and an ultrafast scintillation rise time of ~ 50 ps, making them promising materials for time resolved applications. Moreover, nanocrystalline hetero-ligand Zr-based MOFs with high luminescent quantum yield and large Stokes shift emission were engineered by coassembly donor and acceptor chromophores, diphenyl anthracene (DPA) and diphenyl tetracene (DPT) moieties, respectively, to generate reabsorption-free emitters with potential applications in bioimaging, solar luminescent concentrators and bulk scintillators.[3] The two luminescent ligands, with similar molecular length and topology, were homogeneously inserted inside the MOF nanocrystals as proven by 129Xe hyperpolarized NMR experiments. The overlap between the emission frequency of DPA molecule and the absorption spectrum of DPT, and the precise spat