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The influence of defects and local stresses on the magnetic properties and martensitic transformation in Ni50Mn35Sn15 is studied at macroscopic and atomic scale levels. We show that both the structural and magnetic properties of the alloy are very sensitive to slight microstructural distortions. Even though no atomic disorder is induced by milling, the antiphase boundaries linked to dislocations promote the antiferromagnetic coupling of Mn, resulting in a significant decrease in the saturation magnetization. On the other hand, the temperature range of the transformation is considerably affected by the mechanically induced local stresses, which in turn does not affect the equilibrium temperature between the austenitic and martensitic phases. Finally, we demonstrate that the recovery of the martensitic transformation is directly related to the intensity of the non-magnetic component revealed by 119Sn Mössbauer spectroscopy. This result opens the possibility of quantifying the whole contribution of defects and the local stresses on the martensitic transformation in Ni-Mn-Sn alloys. [ABSTRACT FROM AUTHOR]

Emission Mössbauer spectroscopy has been utilised to characterize dilute Fe impurities in In O following implantation of Mn ( T = 1.5 min.) at the ISOLDE facility at CERN. From stoichiometry considerations, one would expect Fe to adopt the valence state 3 + , substituting In , however the spectra are dominated by spectral lines due to paramagnetic Fe. Using first principle calculations in the framework of density functional theory (DFT), the density of states of dilute Fe and the hyperfine parameters have been determined. The hybridization between the 3d-band of Fe and the 2p band of oxygen induces a spin-polarized hole on the O site close to the Fe site, which is found to be the cause of the Fe state in In O. Comparison of experimental data to calculated hyperfine parameters suggests that Fe predominantly enters the 8b site rather than the 24d site of the cation site in the Bixbyite structure of In O. A gradual transition from an amorphous to a crystalline state is observed with increasing implantation/annealing temperature. [ABSTRACT FROM AUTHOR]

Fe emission Mössbauer spectroscopy has been applied to study the lattice location and properties of Fe in gadolinium gallium garnet GdGa O (GGG) single crystals in the temperature interval 300 - 563 K within the extremely dilute (<10 at.%) regime following the implantation ofMn ( T= 1.5 min.) at ISOLDE/CERN. These results are compared with earlier Mössbauer spectroscopy study of Fe-doped gadolinium gallium garnet GdGa O(GGG), with implantation fluences between 8×10 and 6×10 atoms cm. Three Fe components are observed in the emission Mössbauer spectra: (i) high spin Fe located at damage sites due to the implantation process, (ii) high spin Fe at substitutional tetrahedral Ga sites, and (iii) interstitial Fe, probably due to the recoil imparted on the daughterFe nucleus in the β decay ofMn. In contrast to high fluenceFe implantation studies the Fe ions are found to prefer the tetrahedral Ga site over the octahedral Ga site. No annealing stages are evident in the temperature range investigated. Despite the very low concentration, high-spin Fe shows fast spin relaxation, presumably due to an indirect interaction between nearby gadolinium atoms. [ABSTRACT FROM AUTHOR]

The influence of both the Co addition and the internal stress on the atomic level magnetism is comparatively studied in Ni 50 Mn 37 Sn 13 and Ni 45 Mn 38 Sn 13 Co 4 alloys by magnetic measurements and 119 Sn Mössbauer spectroscopy. The results show that the saturation magnetization and the hyperfine field follow the same temperature trend. The internal stress state is investigated by subjecting the samples to milling and annealing treatments, and tracking the singlet component revealed by 119 Sn Mössbauer spectroscopy. Contrary to what was expected, in the Co-doped Ni-Mn-Sn sample the singlet component can be resolved between the milled and annealed states in both martensite and austenite phases. Therefore, the results demonstrate the feasibility of tracking the singlet component upon the structural recovery in Co-doped Ni-Mn-Sn alloys in a much wider range than in ternary alloys. In addition, it is concluded that the transferred dipolar field at Sn from the neighbor magnetic atoms depends very strongly on the stress field and on the microstructural order surrounding Sn atoms. The observed sensitivity of Sn Mössbauer probe atoms to slight microstructural distortions make 119 Sn a powerful technique for the characterization of the stress present in Sn containing metamagnetic shape memory alloys. [ABSTRACT FROM AUTHOR]

The effect of combined mechanical and thermal treatments in the magnetostructural properties is studied in a Ni-Mn-Sn metamagnetic shape memory alloy, by X-ray diffraction, powder neutron diffraction, calorimetry, magnetometry and 119Sn Mössbauer spectroscopy. A Ni50Mn35Sn15 alloy has been mechanically milled and then annealed at different temperatures in order to produce different microstructural states. The milling and the post-annealing processes do not produce any variation of transition temperatures and atomic order. However, the induced microstructural distortions affect greatly the martensitic transformation. Milling promotes antiferromagnetic coupling between Mn atoms, resulting in a significant decrease in the saturation magnetization that recovers with annealing. Moreover, the temperature width of the transformation is considerably affected by the mechanically induced local strain. Last but not least, the recovery of the microstructural distortions induced by milling is directly related to the intensity of the non-magnetic component revealed by 119Sn Mössbauer spectroscopy. This result opens the possibility of quantifying the whole contribution of defects and local strain on the martensitic transformation in Ni-Mn-Sn alloys. [ABSTRACT FROM AUTHOR]

Bi2Se3, which belongs to the family of topological insulators. We experimentally demonstrate that selenium vacancy defects (VSe1) are present in Bi2Se3 as-grown samples, and that their charge is delocalized as temperature increases. At least from 100 K up to room temperature both VSe10 and VSe1+ charge states coexist. The observed charge delocalization determines the contribution of VSe1 defects to the n-type conductivity of Bi2Se3. These findings are supported by theoretical calculations, which show that vacancies of nonequivalent Se1 and Se2 selenium atoms are clearly differentiated by positron annihilation lifetime spectroscopy, enabling us to directly detect and quantify the most favorable type of selenium vacancy. In addition to open-volume defects, experimental data indicate the presence of defects that act as shallow traps, suggesting that more than one type of native defects coexist in Bi2Se3. As will be discussed, the presence of a dislocation density around 1010cm-2 could be the source of the detected shallow traps. Understanding the one-dimensional defects and the origin of the charge delocalization that leads Bi2Se3 to be an n-type semiconductor will help in the development of high-quality topological insulators based on this material. [ABSTRACT FROM AUTHOR]

Introduction: The professional dedicated to respiratory health has an exemplary role in tobacco control, promoting smoking cessation in their patients. However, multiple circumstances cause a low implementation. Therefore, the objective of the study is to identify the consumption, knowledge and perception of tobacco and its emerging products in a representative sample of professionals involved in the treatment of respiratory patients integrated into the Spanish Society of Pneumology and Thoracic Surgery (SEPAR)., Methods: Descriptive analysis of a structured online interview addressed to 5340 SEPAR members., Results: In a sample of 802 respondents, more than 33% have smoked at some time and 6.6% continue to smoke. More than 66% consider smoking as a chronic disease. More than 90% consider their role model important and advise their patients to quit smoking, but less than half carry out a smoking intervention. Only 35% of them believe that the ban on smoking in health centers is always complied. More than 75% do not consider nicotine delivery devices an option for smoking cessation or harm reduction. 22% are unaware of water pipes and 29% of heated tobacco., Conclusions: Professionals specialized in respiratory diseases are highly sensitized to smoking. Despite this, there are still weak points such as the insufficient implementation of smoking cessation interventions or the scant training in smoking and in new emerging products., (© 2023 Sociedad Española de Neumología y Cirugía Torácica (SEPAR). Published by Elsevier España, S.L.U.)

Prostate cancer is one of the most common cancers among men. Although many patients respond favorably to first-line treatments, castration-and chemotherapy-resistance arises after a few years, leading to metastasis. Thus, new approaches are being investigated using natural supplements to reinforce current therapies. Ocoxin is a plant-based mixture with antitumor properties that have been proved in several cancers. Here, we evaluated the cytotoxic capacity of this compound itself and combined with Docetaxel, Enzalutamide and Olaparib as an adjuvant agent. We observed that Ocoxin reduced tumor cell viability; slowed down cell cycles; altered the expression of genes involved in DNA replication, cell cycles and the p53 signaling pathway; and reduced migratory capacity after stimulation with cancer-associated fibroblasts (CAFs) and osteoblasts in vitro and reduced tumor volume in vivo. The combination of the nutritional supplement with chemotherapy showed a higher cytotoxic effect than chemotherapy alone and reverted chemoresistance conferred by CAFs and osteoblasts. Moreover, the adjuvant therapy also improved the outcome in vivo compared to the treatment with solo chemotherapy, where mice developed smaller tumors and less angiogenesis. Therefore, Ocoxin arises as a good candidate for further studies in combination with current treatments for prostate-cancer patients.

Whereas the prevalence of several cancer types is decreasing, skin malignancies are growing more common every year. Malignant melanoma is the most aggressive form of skin cancer with high metastatic capacity. In most cases, malignant melanoma shows acquired therapy resistance. We evaluated the ability of Ocoxin, a natural compound-based antioxidant and anti-inflammatory nutritional complement, to exert an antitumor effect in melanoma. To do so, the cytotoxicity of Ocoxin in a panel of BRAF-mutated murine and human melanoma cell lines was tested alone and in combination with BRAF inhibitor Vemurafenib. Our results revealed a potent cytotoxic effect of Ocoxin against melanoma cells and a synergic effect when combined with Vemurafenib, reducing viability and increasing apoptosis. Besides, Ocoxin interferes with the cell cycle, impairs the inherent and fibroblast-mediated melanoma cell migration, and reduces resistance to BRAF inhibition. Proteomic analysis revealed reduced tumor secretion of inflammatory factors Galectin-1, Osteopontin, CCL5, and CCL9 upon treatment with Ocoxin. Moreover, RNASeq showed that Ocoxin downregulated the cell cycle and proliferation-related genes. In vivo, Ocoxin reduced the number of lung metastasis of YUMM-1.7 melanoma cells. Therefore, Ocoxin arises as a good candidate for clinical trials analyzing the beneficial effects in patients suffering from this cutaneous malignancy.

The change in the Curie temperature of single crystalline garnet Y 3 Fe 5 O 12 (YIG) sample due to lattice damage induced by ion implantation has been investigated in 57 Fe emission Mössbauer Spectroscopy (eMS) following implantation of 57 Mn (T ½  = 1.5 min). The Mössbauer spectra analysis reveal high spin Fe 3+ ions substituted on both the octahedral and the tetrahedral sites. Measurements in the temperature range 298 K-798 K show that average values of the magnetic hyperfine field are decreased by the implantation-induced damage on the local lattice structure of the YIG. The Curie temperature, however, is determined to be 651 ± 5 K, considerably higher than the value of bulk YIG (559 K). This is most likely due to lattice damage-induced changes on the spin configurations of YIG through a Fe A -O-Fe D distortion scheme., Competing Interests: Declaration of competing interest We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objectives: Pancreatic carcinoma is one of the most aggressive cancers overcoming chemoresistance. Thus, novel compounds to complement the current antitumor agents are in need. Ocoxin oral solution (OOS) has proven antioxidant, anti-inflammatory, and antistromagenic properties. The aim of this study was to analyze the effect of OOS in an experimental pancreatic cancer model and its implication in stroma-related chemoresistance to paclitaxel and gemcitabine., Methods: Murine pancreatic carcinoma 266-6 cells were treated with OOS to analyze cell cycle and to perform a mRNA comparative microarray study. Then the viability was assessed in combination with paclitaxel and/or gemcitabine. Chemoresistance induced by the medium taken from fibroblast cultures was also investigated on 6 human pancreatic carcinoma cell lines. Furthermore, an experimental model of pancreatic cancer was carried out to study the effect of OOS in vivo., Results: Ocoxin oral solution enhances the cytotoxic effect of paclitaxel and gemcitabine, while it ameliorates the chemoresistance induced by fibroblast-derived soluble factors in human pancreatic cancer cells. The OOS also promotes the regulation of the expression of genes that are altered in pancreatic carcinoma and slows down 266-6 cell pancreatic tumor development in vivo., Conclusions: Ocoxin oral solution could be a potential complement to the chemotherapeutic drugs for pancreatic adenocarcinoma.

Colorectal cancer (CRC) is an aggressive disease in which patients usually die due to its metastatic progression to the liver. Up to date, irinotecan is one of the most used chemotherapeutic agents to treat CRC metastasis with demonstrated efficacy. However, the severity of the side effects constitute the main limitation to its use in the treatment. Consequently, new complementary therapies are being developed to avoid these adverse effects while maintaining the efficacy of the antitumoral drugs. Ocoxin oral solution (OOS ® ) is a nutritional mixture containing biologically active compounds with demonstrated antitumoral and immunomodulatory effects. Thus, we aimed to analyze the effect of OOS ® as a suitable complement to irinotecan therapy in the treatment of CRC metastasis to the liver. First, the effect of OOS ® , irinotecan and the combination of both on the viability of C26 cells was tested in vitro and in vivo . Second, the expression of caspase-3, Ki67 and the macrophage infiltration by F4/80 marker was quantified in liver tissue sections by immunohistochemistry. Finally, mRNA microarray study was carried out on tumor cells isolated from tumor-bearing livers collected from mice subjected to the above treatments. Our results show that OOS ® administered as a complementary therapy to irinotecan reduced tumor cell viability in vitro . Moreover, irinotecan administered either alone or in combination with 100 µl OOS ® from the 7th day after tumor cell inoculation decreased the metastatic growth in the liver. Besides, several genes with binding and catalytic activities showed to be deregulated by RNA microarray analysis. In conclusion, OOS ® , when administered as a complement to irinotecan, reduced the metastatic development of colorectal cancer to the liver. Additionally, the overall health state of the animals improved. These results point out OOS ® as a potential supplement to the anti-tumoral treatments used in clinical settings in patients suffering from disseminated colorectal cancer.