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This study investigates the fabrication process of copper thin films via thermal evaporation, with precise control over film thickness achieved throughZ-position adjustment. Analysis of the as-fabricated copper films reveals a discernible relationship between grain size (〈D〉) andZ-position, characterized by a phenomenological equation〈D〉XRDn(Z)=〈D〉0n1+32rZ2+158rZ4, which is further supported by a growth exponent (n) of 0.41 obtained from the analysis. This value aligns well with findings in the literature concerning the growth of copper films, thus underlining the validity and reliability of our experimental outcomes. The resulting crystallites, ranging in size from 20 to 26 nm, exhibit a resistivity within the range of 3.3-4.6µΩ · cm. Upon thermal annealing at 200 °C, cuprite Cu2O thin films are produced, demonstrating crystallite sizes ranging from ∼9 to ∼24 nm with increasing film thickness. The observed monotonic reduction in Cu2O crystallites relative to film thickness is attributed to a recrystallization process, indicating amorphization when oxygen atoms are introduced, followed by the nucleation and growth of newly formed copper oxide phase. Changes in the optical bandgap of the Cu2O films, ranging from 2.31 to 2.07 eV, are attributed mainly to the quantum confinement effect, particularly important in Cu2O with size close than the Bohr exciton diameter (5 nm) of the Cu2O. Additionally, correlations between refractive index and extinction coefficient with film thickness are observed, notably a linear relationship between refractive index and charge carrier density. Electrical measurements confirm the presence of a p-type semiconductor with carrier concentrations of ∼1014cm-3, showing a slight decrease with film thickness. This phenomenon is likely attributed to escalating film roughness, which introduces supplementary scattering mechanisms for charge carriers, leading to a resistivity increase, especially as the roughness approaches or surpasses the mean free path of charge carriers (8.61 nm). Moreover,ab-initiocalculations on the Cu2O crystalline phase to investigate the impact of hydrostatic strain on its electronic and optical properties was conducted. We believe that our findings provide crucial insights that support the elucidation of the experimental results. Notably, thinner cuprite films exhibit heightened sensitivity to ethanol gas at room temperature, indicating potential for highly responsive gas sensors, particularly for ethanol breath testing, with significant implications for portable device applications.

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A 34-year-old male was admitted with presumed acute, severe aortic regurgitation. Multimodal imaging was performed and showed a ruptured right coronary sinus of Valsalva aneurysm into the right atrium. He underwent a percutaneous closure of the ruptured sinus of Valsalva aneurysm. The patient had major clinical improvement.

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In the Amazon region, Trypanosoma cruzi transmission cycles involve a great diversity of Triatominae vectors and mammal reservoirs. Some Rhodnius spp. mainly inhabit palm trees that act as microhabitats for hosts and vectors. The current study aimed to describe aspects of the bio-ecology of the vectors and reservoirs of T. cruzi in relation to human populations resident near areas with large quantities of palm trees, in rural, peri-urban and urban collection environments, located in the Western Brazilian Amazon. Rhodnius pictipes and Didelphis marsupialis were respectively the most predominant vector and reservoir, with rates of 71% for R. pictipes and 96.5% for D. marsupialis. The vast majority of T. cruzi isolates clustered with TcI. The most prevalent haplotype was TcI COII1 (69.7%). Mauritia flexuosa and Attalea phalerata were the main ecological indicators of infestation by triatomines. Birds were the most common food source (27,71%). T. cruzi isolated from R. robustus has the haplotype HUM-13, previously detected in a chronic Chagas patient living in the same area. Our results demonstrate the relevance of this study, with the occurrence of elevated infection rates in animals, and suggest the importance of the Amazon zones where there is a risk of infection in humans.

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PURPOSE: Several studies have found an association between peripheral inflammatory cells and outcome. However, no study has explored their impact specifically in elderly patients. We have retrospectively examined pretreatment peripheral neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio (LMR), and neutrophil/monocyte ratio (NMR) in 113 elderly breast cancer patients and correlated our findings with disease-free survival (DFS) and overall survival (OS). METHODS: All patients ≥ 65 years diagnosed from 2004 to 2018 with locally advanced breast cancer were included and classified as high vs low NLR, PLR, LMR, and NMR based on previously identified cutoffs. Estimated 1-, 3-, and 5-year DFS and OS were compared by Chi square analysis. RESULTS: Among 104 evaluable patients, only PLR was significantly associated with estimated 3-year DFS (85.1% vs 63.6%; P = 0.04) and OS (89.3% vs 68.1%; P = 0.03). Among 69 patients with three or more years of follow-up, PLR (P = 0.05), absolute lymphocyte count (ALC) (P = 0.01), polychemotherapy (P = 0.04), number of comorbidities (P = 0.02), polypharmacy (P = 0.005), and clinical stage (P = 0.03) were associated with 3-year DFS. Polypharmacy (OR 4.9; P = 0.02) and ALC (OR 4.6; P = 0.04) retained their significance in the multivariate analysis. CONCLUSIONS: We have found an association between low PLR and longer DFS in elderly breast cancer patients that is in line with findings in patients with a wider range of ages. Our findings on NLR contrast with those of other studies, indicating a potential differential effect in elderly patients. In addition, the effect of polypharmacy on outcome in elderly patients warrants further investigation.

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To improve survival in young children with malignant brain tumors, irradiation-avoiding or -minimizing marrow-ablative chemotherapy (HDCx) with autologous hematopoietic cell transplantation (AuHCT) has been investigated. We evaluated the outcome of 44 children with malignant brain tumors treated with HDCx and tandem AuHCT at Children's Hospital Los Angeles between June 1999 and July 2012. Forty-four children with malignant brain tumors were studied. Twenty-one had medulloblastoma/primitive neuro-ectodermal tumor, eight atypical teratoid/rhabdoid tumor (ATRT), five high-grade glioma, four malignant germ cell tumor, three ependymoma and three choroid plexus carcinoma. Twenty-nine patients received three tandem transplants and 15 received two tandem transplants, respectively. The 5-year PFS and overall survivals (OS) for all patients were 46.3±8.2% and 51.7±8.5%, respectively. The PFS and OS for 27 newly diagnosed patients were 68.9±9.9% and 73.5±9.3%, respectively, compared with 17 transplanted at relapse 11.8±9.8% (P<0.001) and 15.1±12.3% (P=0.0231), respectively. The 5-year PFS and OS in 13 previously unirradiated patients were 74±13% and 74±13% versus 33.2±9.8% and 40.2±10.6% in 31 irradiated patients (P=0.11 and P=0.239), respectively. One patient died of transplant-related toxicity. HDCx with tandem AuHCT is feasible and safe in children with malignant brain tumors with encouraging irradiation-free survival in newly diagnosed children.

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Functional variations in the mannose-binding lectin (MBL2) gene causing low levels of serum MBL are associated with susceptibility to numerous infectious diseases. We investigated whether there is genetic association of MBL2 variant alleles with cutaneous leishmaniasis (CL) caused by Leishmania guyanensis. We used PCR-restriction fragment length polymorphism to genotype six MBL2 variants, three in the promoter region and three in the exon 1. An association was noted between the single nucleotide polymorphism -221X/Y of the MBL2 gene and CL (P=2.9 × 10(-6); odds ratio (OR)=1.9 (1.4-2.5) consistent with the hypothesis that the -221X allele confers high risk to development of CL among L. guyanensis-infected individuals. Furthermore, L. guyanensis-infected individuals bearing the codon 57 allele C had a higher risk of developing CL (P=5 × 10(-5); OR=1.9 (1.4-2.6)). The low MBL expressor haplotype LXPB was also associated to CL (P=6 × 10(-4)). This study raises the possibility that functional polymorphisms in MBL2 gene play a role in clinical outcome of Leishmania infection.

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Polyurethane-based micro- and nano-hybrid composites were produced with controlled porosity to be used as obturation materials. In addition to hydroxyapatite (HAp) micro-particles in the composites, two different ceramics particle types were also added: alumina micro-particles and silica nano-particles. Particles of different sizes provide the materials with improved mechanical properties: the use of micro- and nano-particles produces a better packing because the nano-particles fill the interstitial space left by the micro-particles, rendering an improvement in the mechanical properties. The silica and alumina particles provide the materials with appropriate abrasion and scratching properties, while the HAp provides the required bio-acceptance. The polymeric matrix was a mono-component solvent-free polyurethane. The porosity was selected by controlling the chemical reaction.

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Los tumores metastásicos del hueso temporal son relativamente infrecuentes, si bien su incidencia real parece mayor de lo que habitualmente se considera. El diagnostico precoz solamente es posible si existe una sospecha clinica importante. La existencia de otalgia persistente acompañada de parálisis facial debe alertarnos ante la posibilidad de un tumor metastásico en el hueso temporal. Sin embargo, la existencia de sintomatologia suele indicar un estadio avanzado de la enfermedad, siendo el pronostico pobre para la mayoria de los pacientes. Presentamos un caso de metastasis de adenocarcinoma de ovario localizada en el hueso temporal. Se trata del segundo caso publicado hasta la fecha con origen en el ovario

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