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Development of technologies which utilize hydrogen as energy vector requires the realization of efficient gas storage systems. Materials suitable for hydrogen storage at the solid state have to fulfill some specific requirements in order to be used inside the reactors. First of all it is necessary to have a material which could be cycled without observing reduction of performances in terms of kinetics and total hydrogen capacity. The reaction of the material with hydrogen must be reversible even after long time cycling, i.e. repeated absorption and desorption runs. For what concerns the efficiency of the reactors, one of the main parameters to be taken into account is the thermal conductivity of the bed of hydride. The use of powder is detrimental for thermal conductivity and also for gas permeability and particle entrainment by the gas flow in the reactor. Moreover powders after long term cycling tend to pack and sinter evidencing the problems reported before. For this reason powders of hydrides are compacted, generally in cylindrical shape, after mixing with agents for enhancing thermal conductivity and mechanical stability (for example Al, Cu, carbon-based materials). It has been reported that compacted systems during cycling tend to disaggregate returning to the form of powder in the loose form. This swelling mechanism causes rapid slowdown of the kinetics and all the problems correlated to the use of the powders. For this reason many efforts have been spent in order to extend the life of the compacted systems. In this work it is reported the study performed to improve the preparation of compacted powder systems by a procedure which includes the deposition of a thin layer of a metal on the surface of the pellet. The pellets prepared with this procedure demonstrated, after 50 cycles, variations of dimension eight time lower in comparison to those obtained on pellets prepared without coating. The quantity of metal deposited is less than 0.1% of the weight of the pellet and it doesn't affect hydrogen capacity and kinetics of reaction. Kinetics of reaction and microstructure have been studied with a volumetric Sievert's type apparatus and with Optical and Scanning Electron Microscopy respectively. [ABSTRACT FROM AUTHOR]

The study of materials for space exploration is one of the most interesting targets of international space agencies. An essential tool for realizing light junctions is epoxy adhesive (EA), which provides an elastic and robust material with a complex mesh of polymeric chains and crosslinks. In this work, a study of the structural and chemical modification of a commercial two-part flexible EA (3M™ Scotch-Weld™ EC-2216 B/A Gray), induced by 60 Co gamma radiation, is presented. Combining different spectroscopic techniques, such as the spectroscopic Fourier transform infrared spectroscopy (FTIR), the THz time-domain spectroscopy (TDS), and the electron paramagnetic resonance (EPR), a characterization of the EA response in different regions of the electromagnetic spectrum is performed, providing valuable information about the structural and chemical properties of the polymers before and after irradiation. A simultaneous dissociation of polymeric chain and crosslinking formation is observed.The polymer is not subject to structural modification at an absorbed dose of 10 kGy, in which only transient free radicals are observed. Differently, between 100 and 500 kGy, a gradual chemical degradation of the samples is observed together with a broad and long-living EPR signal appearance. This study also provides a microscopic characterization of the material useful for the mechanism evaluation of system degradation.

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 CsPbBr 3 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.

Black fungi are among the most resistant organisms to ionizing radiation on Earth. However, our current knowledge is based on studies on a few isolates, while the overall radioresistance limits across this microbial group and the relationship with local environmental conditions remain largely undetermined. To address this knowledge gap, we assessed the survival of 101 strains of black fungi isolated across a worldwide spatial distribution to gamma radiation doses up to 100 kGy. We found that intra and inter-specific taxonomy, UV radiation, and precipitation levels primarily influence the radioresistance in black fungi. Altogether, this study provides insights into the adaptive mechanisms of black fungi to extreme environments and highlights the role of local adaptation in shaping the survival capabilities of these extreme-tolerant organisms., (© 2023 The Authors. Environmental Microbiology published by Applied Microbiology International and John Wiley & Sons Ltd.)

Nanoparticles are being increasingly studied to enhance radiation effects. Among them, nanodiamonds (NDs) are taken into great consideration due to their low toxicity, inertness, chemical stability, and the possibility of surface functionalization. The objective of this study is to explore the influence of the chemical/physical properties of NDs on cellular radiosensitivity to combined treatments with radiation beams of different energies. DAOY, a human radioresistant medulloblastoma cell line was treated with NDs-differing for surface modifications [hydrogenated (H-NDs) and oxidized (OX-NDs)], size, and concentration-and analysed for (i) ND internalization and intracellular localization, (ii) clonogenic survival after combined treatment with different radiation beam energies and (iii) DNA damage and apoptosis, to explore the nature of ND-radiation biological interactions. Results show that chemical/physical characteristics of NDs are crucial in determining cell toxicity, with hydrogenated NDs (H-NDs) decreasing either cellular viability when administered alone, or cell survival when combined with radiation, depending on ND size and concentration, while OX-NDs do not. Also, irradiation at high energy (γ-rays at 1.25 MeV), in combination with H-NDs, is more efficient in eliciting radiosensitisation when compared to irradiation at lower energy (X-rays at 250 kVp). Finally, the molecular mechanisms of ND radiosensitisation was addressed, demonstrating that cell killing is mediated by the induction of Caspase-3-dependent apoptosis that is independent to DNA damage. Identifying the optimal combination of ND characteristics and radiation energy has the potential to offer a promising therapeutic strategy for tackling radioresistant cancers using H-NDs in conjunction with high-energy radiation.

Introduction: Future long-term space missions will focus to the solar system exploration, with the Moon and Mars as leading goals. Plant cultivation will provide fresh food as a healthy supplement to astronauts' diet in confined and unhealthy outposts. Ionizing radiation (IR) are a main hazard in outer space for their capacity to generate oxidative stress and DNA damage. IR is a crucial issue not only for human survival, but also for plant development and related value-added fresh food harvest. To this end, efforts to figure out how biofortification of plants with antioxidant metabolites (such as anthocyanins) may contribute to improve their performances in space outposts are needed., Methods: MicroTom plants genetically engineered to express the Petunia hybrida PhAN4 gene, restoring the biosynthesis of anthocyanins in tomato, were used. Seeds and plants from wild type and engineered lines AN4-M and AN4-P 2 were exposed to IR doses that they may experience during a long-term space mission, simulated through the administration of gamma radiation. Plant response was continuously evaluated along life cycle by a non-disturbing/non-destructive monitoring of biometric and multiparametric fluorescence-based indices at both phenotypic and phenological levels, and indirectly measuring changes occurring at the primary and secondary metabolism level., Results: Responses to gamma radiation were influenced by the phenological stage, dose and genotype. Wild type and engineered plants did not complete a seed-to-seed cycle under the exceptional condition of 30 Gy absorbed dose, but were able to cope with 0.5 and 5 Gy producing fruits and vital seeds. In particular, the AN4-M seeds and plants showed advantages over wild type: negligible variation of fluorimetric parameters related to primary metabolism, no alteration or improvement of yield traits at maturity while maintaining smaller habitus than wild type, biosynthesis of anthocyanins and maintained levels of these compounds compared to non-irradiated controls of the same age., Discussion: These findings may be useful in understanding phenotypic effects of IR on plant growth in space, and lead to the exploitation of new breeding efforts to optimize plant performances to develop appropriate ideotypes for future long-term space exploration extending the potential of plants to serve as high-value product source., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Pagliarello, Bennici, Di Sarcina, Villani, Desiderio, Nardi, Benvenuto, Cemmi and Massa.)

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 CsPbBr 3 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., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Gene expression manipulation of specific metabolic pathways can be used to obtain bioaccumulation of valuable molecules and desired quality traits in plants. A single-gene approach to impact different traits would be greatly desirable in agrospace applications, where several aspects of plant physiology can be affected, influencing growth. In this work, MicroTom hairy root cultures expressing a MYB-like transcription factor that regulates the biosynthesis of anthocyanins in Petunia hybrida ( PhAN4 ), were considered as a testbed for bio-fortified tomato whole plants aimed at agrospace applications. Ectopic expression of PhAN4 promoted biosynthesis of anthocyanins, allowing to profile 5 major derivatives of delphinidin and petunidin together with pelargonidin and malvidin-based anthocyanins, unusual in tomato. Consistent with PhAN4 features, transcriptomic profiling indicated upregulation of genes correlated to anthocyanin biosynthesis. Interestingly, a transcriptome reprogramming oriented to positive regulation of cell response to biotic, abiotic, and redox stimuli was evidenced. PhAN4 hairy root cultures showed the significant capability to counteract reactive oxygen species (ROS) accumulation and protein misfolding upon high-dose gamma irradiation, which is among the most potent pro-oxidant stress that can be encountered in space. These results may have significance in the engineering of whole tomato plants that can benefit space agriculture., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Massa, Pagliarello, Cemmi, Di Sarcina, Bombarely, Demurtas, Diretto, Paolini, Petzold, Bliek, Bennici, Del Fiore, De Rossi, Spelt, Koes, Quattrocchio and Benvenuto.)

PLAnetary Transits and Oscillations of stars (PLATO) is a medium sized mission (M3) selected by the European Space Agency (ESA) for launch in 2026. The PLATO payload includes 26 telescopes all based on a six-element refractive optical scheme. Some components will be eventually manufactured by S-FPL51, N-KZFS11 and S-FTM16 glass whose radiation resistance is partially or totally unknown. The radiation-resistance properties of such materials have been investigated by using a 60 Co γ-rays source as probe. Each optical component has been characterized by a depth profile curve which describes the transmission loss as a function of the thickness in dependence of the impinging dose. A model to simulate the throughput of the whole instrument has been developed and used to verify the instrument performance considering different stellar spectra.

Background and Aims: Data on the potential of circulating tumor cells (CTC) count in predicting overall survival (OS) in patients with colorectal cancer are timely and worthy of interest. This study aimed to evaluate the prognostic role of CTC count in both localized and metastatic colorectal cancer patients., Methods: Consecutive patients with histological diagnosis of colorectal cancer were enrolled. CTC count was performed, by using a quantitative immunofluorescence method, at baseline (T0) and 1 month following start of chemotherapy (T1). A CTC count <2 was considered negative, whilst a CTC level >/= 2 was positive. Overall survival was calculated accordingly., Results: A total of 75 colorectal cancer patients were enrolled, including 54 stages I-III and 21 stage IV patients. Overall, 21 (28%) patients had a positive CTC count at baseline, and it was significantly associated with a worse prognosis as compared to a negative status (OS: 36.2 vs. 61.6 months; P = 0.002). CTC count remained positive after chemotherapy in 22.4% of the patients and it was an independent prognostic factor of OS (P = 0.03; Hazard Ratio: 3.55; 95% CI: 1.1-11.5)., Conclusions: This study found that the presence of CTCs is associated with a reduced survival in colorectal cancer patients. Further studies aimed at testing such a predictive value in early stage colorectal cancer are awaited.

Optical materials and coatings are exposed to the flux of energetic particles when used in either space applications or nuclear energy plants. The study of their behavior in such an environment is important to avoid failure of the optical components during their operation. The optical performance of several thin-film materials ((HfO2, Ta2O5, Nb2O5, TiO2, SiO2) and coatings, under irradiation with high-dose gamma rays (5.8 MGy) and exposure to low-energy (60 keV) protons, has been investigated. Some variations of optical properties have been detected in silicon oxide after irradiation, while the other materials are stable in such conditions.

Purpose: Over the past few years, more and more new selective molecules directed against specific cellular targets have become available for cancer therapy, leading to impressive improvements. In this evolving scenario, a new way of delivering older cytotoxic drugs has also been developing. Many studies demonstrated that several cytotoxic drugs have antiangiogenic properties if administered frequently and at lower doses compared with standard schedules containing maximal tolerated doses (MTD). Such a new strategy, named metronomic chemotherapy, focuses on a different target: the slowly proliferating tumour endothelial cells. About 10 years ago, metronomic chemotherapy was firstly enunciated and hereafter many clinical experiences were published related to almost any cancer disease. This review analyses available studies dealing with metronomic chemotherapy and its combination with several targeted agents in solid tumours., Methods: A computerized literature search of MEDLINE was performed using the following search terms: metronomic OR "continuous low dose" AND chemotherapy AND cancer OR solid tumours., Results: Satisfactory results have been achieved in diverse tumour types, such as breast and prostate cancer or paediatric sarcomas. Moreover, many studies have reported that metronomic chemotherapy determined minimal toxicity compared to MTD chemotherapy. Overall, published series on metronomic schedules are very heterogeneous often reporting on retrospective data, while only very few studies were randomized trials. These limitations still prevent to draw definitive conclusions in diverse tumour types., Conclusions: Large well-designed studies are eagerly awaited for confirming the promises of metronomic schedules and their combinations with targeted molecules.

Background: The biliary tract carcinomas rank fifth in incidence among all gastrointestinal tumours. This group of tumours includes both cholangiocarcinoma and gallbladder carcinoma. Although surgery represents the main therapeutic option for these patients, both radiotherapy and chemotherapy could be used in a multidisciplinary approach. Several studies are currently available on the use of chemotherapy, including 5-fluorouracil, mitomycin C, methotrexate, doxorubicin and cisplatin or newer anticancer molecules, such as gemcitabine, capecitabine, oxaliplatin and irinotecan. However, the small sample size of most of these studies prevents generalization., Discussion: We reviewed the available data on both chemotherapy and targeted therapies for biliary carcinoma. By using conventional chemotherapy, a response rate ranging from 10% to 40% has been reported. Although encouraging data emerged with the use of targeted therapies, further efforts are needed to improve treatment options for patients with biliary tract cancer.

Carcinomas of the Ampulla of Vater are rare tumors, accounting for 0.2% of gastrointestinal cancers. Compared with other biliary tract neoplasms, these tumors have a relatively favorable prognosis after surgical resection. Based on their epithelium of origin, two subtypes of ampullary carcinoma have been recently distinguished: intestinal and pancreatobiliary. This study evaluates histopathological features and outcomes of ampullary carcinoma and to compares the survival of these tumors to that of other biliary tract tumors. The chemotherapic options available for ampullary cancer are also reviewed. We analyzed data from 20 consecutive patients with ampullary carcinomas and 26 patients with other biliary tract carcinomas, observed in our Institution. Statistical analysis was performed by using either Fisher's exact test or χ(2) test for categorical variables. Median time of survival was calculated and compared using the Log-Rank test. Similar distribution of demographic characteristics and stage between ampullary and other biliary tract cancers was observed. Patients with ampullary cancer underwent surgery more frequently than other biliary cancers while chemotherapy and radiotherapy were used equally. In accordance with the literature, a longer median survival was observed in the group of ampullary carcinomas.

Background: A possible anticancer role for somatostatin has been suggested. This study assessed the presence of somatostatin receptor subtype 2A (SSTR2A) in gastric cancer, correlating its expression with histological type, grade, human epidermal growth factor receptor 2 (HER2) expression, and disease outcome., Materials and Methods: Gastric cancer tissues of 51 consecutive patients were collected for immunohistochemical assessment of both SSTR2A and HER2 expression., Results: SSTR2A expression was observed in 38 (74.5%) cases. Prevalence of SSTR2A expression was significantly higher in well to moderately (G1-2) differentiated gastric cancer as compared to poorly (G3) differentiated tumors (96% vs. 52%; p<0.01), as well as in intestinal- than in diffuse-type cancer (97% vs. 20%; p<0.001). HER2 expression was positive in 18 (35%) patients, and it was associated with SSTR2A expression (r=0.50, p<0.001), being co-expressed in 17 (95%) out of 18 positive cases. RFS was significantly lower in patients with diffuse HER2 expression., Conclusion: This study demonstrated a co-localization between SSTR2A and HER2, potentially opening new therapeutic strategies for patients with gastric cancer.

Very narrowband transmission filters, as parts of an instrument for the study of lightning phenomena, are described. Their performance must be maintained at an incidence angle of ±5.5° and this condition poses some limitations on the minimum bandwidth of the order of a few nanometers. The fabrication of such coatings on large area substrates is quite challenging because of the required thickness accuracy. Moreover, their performance should be not influenced by the environmental conditions in space.

Aim: To investigate beta-catenin expression in patients with intestinal metaplasia, and to look for a possible relationship between beta-catenin expression and either epithelial proliferation values or Helicobacter pylori (H pylori) infection., Methods: Twenty patients with complete type intestinal metaplasia were studied. beta-Catenin expression and epithelial cell proliferation in antral mucosa were assessed using an immunohistochemical analysis. H pylori infection was detected by histology and a rapid urease test., Results: Reduced beta-catenin expression on the surface of metaplastic cells was detected in 13 (65%) out of 20 patients. Moreover, in eight (40%) patients intranuclear expression of beta-catenin was found. When patients were analyzed according to H pylori infection, the prevalence of both beta-catenin reduction at the cell surface and its intranuclear localization did not significantly differ between infected and uninfected patients. Cell proliferation was higher in patients with intranuclear beta-catenin expression as compared to the remaining patients, although the difference failed to reach the statistical significance (36+/-8.9 vs 27.2+/-11.4, P = 0.06). On the contrary, a similar cell proliferation value was observed between patients with reduced expression of beta-catenin on cell surface and those with a normal expression (28.1+/-11.8 vs 26.1+/-8.8, P = 0.7). H pylori infection significantly increased cell proliferation (33.3+/-10.2% vs 24.6+/-7.4%, respectively, P = 0.04)., Conclusion: Both cell surface reduction and intranuclear accumulation of beta-catenin were detected in intestinal metaplasia. The intranuclear localization of beta-catenin increases cell proliferation. H pylori infection does not seem to play a direct role in beta-catenin alterations, whilst it significantly increases cell proliferation.

Background: First-degree relatives of gastric cancer patients have an increased risk of developing such neoplasia, and several alterations in gastric mucosa of these subjects have been described. On the other hand, both gastric cell hyperproliferation and abnormalities of adhesion molecules have been involved in gastric carcinogenesis. We studied gastric mucosa alterations in first-degree relatives of gastric cancer patients., Patients and Methods: This prospective, case-controlled study enrolled 39 first-degree relatives of gastric cancer patients and 39 matched controls. Biopsy specimens obtained at endoscopy were used to assess epithelial cell proliferation plus E-cadherin and beta-catenin expression by immunohistochemical methods. H. pylori infection was assessed by histology and a rapid urease test., Results: Gastric epithelial cell proliferation values were not significantly different between the patient and control groups. H. pylori infection significantly increased cell proliferation values both in patients and in controls, without a significant difference between the two groups. Moreover, cell proliferation values were significantly higher in cases harboring intestinal metaplasia than in those without it. Alterations of the adhesion molecules were described exclusively in those patients harboring intestinal metaplasia. In detail, a reduction of both E-cadherin and beta-catenin expression was observed in 8 (67%) out of 12 first-degree relatives and in 6 (67%) out of 9 controls with intestinal metaplasia (p = 0.4). These alterations were similarly distributed between H. pylori infected and uninfected cases., Conclusion: Our data showed that a family history of gastric cancer itself is not associated with gastric cell hyperproliferation. However, both cell hyperproliferation and alterations of adhesion molecules have been detected in those patients with intestinal metaplasia.