Search the repository

A+ | A- | | SLO | ENG

Keywords: jam, pesticide residues, GC-MS/MS, fungicides, insecticides, chromatography, plant products residues
Published in DiRROS: 12.12.2025; Views: 35; Downloads: 16
Full text (549,58 KB)
This document has many files! More...

Abstract: Background: Hypoplastic left heart syndrome (HLHS) was a fatal congenital heart defect (CHD) until the 1980s. Introduction of the Norwood procedure and subsequent Fontan operation significantly improved survival by creating a single-ventricle circulation. Due to the high mortality associated with the Norwood operation, neonatal orthotopic heart transplantation emerged as an alternative, despite challenges such as lifelong immunosuppressive treatment and uncertain longevity of transplanted hearts. Methods: A narrative review with a systematic literature search was conducted in the PubMed, following PRISMA guidelines and included studies of ethical and medical considerations, decision-making, counseling and treatment planning in children with HLHS. In addition, we manually screened reference lists to identify further relevant literature. We aimed to explore: how do ethical considerations and decision-making processes influence the management and outcomes of fetuses and neonates with HLHS and their families across prenatal, postnatal, and long-term care? Results: Of the 115 studies, 56 met the inclusion criteria. Early diagnosis through prenatal fetal ultrasound has markedly improved survival rates by enabling better parental awareness, counseling, and decision-making. Managing HLHS requires urgent, extensive, and costly medical interventions, with outcomes influenced by the healthcare system's expertise, the experience of cardiologists and surgeons, ethical, legal, and religious considerations of the parents and medical team. The prenatal phase is crucial for optimal management, with advanced fetal ultrasound facilitating early detection. Postnatal care involves a multidisciplinary approach, including stage palliation physiology/surgery tailored to each patient. Despite surgical advancements, HLHS patients face higher morbidity and mortality rates than other patients with CHDs, with long-term survival and quality of life remaining key concerns. Ethical considerations play a significant role in the management of HLHS, encompassing the autonomy of families, the best medical interests of the child, societal, and cultural factors. Decision-making must balance full disclosure with sensitivity to parents' values and beliefs. Conclusions: Management of HLHS involves multidisciplinary approach with complex medical and ethical considerations, but the current literature lacks high-quality studies or consensus guidelines on ethical decision-making. Therefore, the influence of ethical considerations on clinical management and patient care remains unclear, highlighting the need for further research.
Keywords: hypoplastic left heart syndrome, congenital heart defect, prenatal diagnosis, neonatal care, palliative surgery, medical ethic, multidisciplinary care, decision making
Published in DiRROS: 12.12.2025; Views: 33; Downloads: 20
Full text (676,27 KB)
This document has many files! More...

Abstract: Radiation-induced defect production in tungsten was studied by a combination of experimental and simulation methods. The analysis of structural defects was performed using multi-energy Rutherford backscattering spectroscopy in channeling configuration (multi-energy C-RBS). To create different microstructures, (111) tungsten (W) single crystals were irradiated with W ions at two different doses (0.02 and 0.2 dpa) at 290 K. Detailed transmission electron microscopy (TEM) analysis of the samples revealed the presence of dislocation lines and loops of different sizes. The RBSADEC code was used to simulate the measured C-RBS spectra, recorded with four different He beam energies along the <111> direction. For the first time for tungsten, molecular dynamics (MD) simulations of overlapping cascades were used as input. The well-known method of randomly displaced atoms (RDA) was applied for comparison. RDA does not provide a satisfactory understanding of the nature of the induced defect structure. With MD, a very good agreement between the simulated and experimental spectra was obtained for the sample prepared at a lower dose, despite the fact that the absolute defect densities are two orders of magnitude higher than those found with TEM. A discrepancy is observed for the high-dose-irradiated sample, which is ascribed to the presence of extended defects such as dislocation lines, which are clearly observed by TEM, but cannot be formed in finite size MD cells. RBSADEC with MD cells as input can describe correctly the response of the RBS signal with analysing beam energy while RDA as input gives the wrong trend.
Keywords: tungsten, defects, Rutherford backscattering spectroscopy in channeling configuration, displacement damage, molecular dynamic simulations, transmission electron microscopy
Published in DiRROS: 12.12.2025; Views: 54; Downloads: 30
Full text (8,29 MB)
This document has many files! More...

Abstract: The effect of near-surface helium (He) on deuterium (D) retention and uptake into the bulk of tungsten (W) was investigated. To quantify the He influence on D uptake, He was implanted close to the surface with 3 keV energy at different fluences and different temperatures. 20 MeV W irradiation was performed at room temperature after He implantation to create defects within the first 2.3 µm. Samples were then exposed to a low flux, low energy (300 eV/D) D ion beam at 450 K. The defects created by W ions trap penetrating D and make it hence possible to quantify D transport into depth below the He layer using 3He nuclear reaction analysis. Elastic recoil detection analysis enabled us to measure the D and He concentration depth profiles near the surface. Results show that D gets preferentially retained where He is implanted with D concentrations up to 10 at.%. At the same time D uptake beyond the He zone is reduced by a factor of 15 compared to a He-free W sample.
Keywords: deuterium retention, displacement damage
Published in DiRROS: 11.12.2025; Views: 75; Downloads: 40
Full text (6,77 MB)
This document has many files! More...

Abstract: We investigated the microstructural evolution of W(111) single crystals under high-energy self-ion irradiation at 290 K and 800 K, using complementary characterization techniques, including Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Rutherford backscattering spectrometry in channelling regime (RBS-C), Positron annihilation spectroscopy (PAS), and Nuclear reaction analysis (NRA). Irradiation with MeV W ions allowed for controlled defect formation, with dose and temperature significantly affecting defect type and distribution. At 290 K, interstitial defects evolved from dislocation loops at low doses (0.02 dpa) to dislocation networks at higher doses (0.2 dpa). In contrast, at 800 K, lower dislocation densities were observed, with nm-sized dots and isolated lines forming at 0.02 dpa and developing into longer dislocation lines (~30 nm) at 0.2 dpa. RBS-C spectra support these findings, showing a trend of increasing dislocation density with dose but decreasing with temperature. PAS analyses revealed mono-vacancies and small vacancy clusters (V2–V4) at 290 K, coalescing into larger clusters (V25–V50) at 800 K. NRA measurements indicated greater deuterium retention at 290 K than at 800 K, consistent with lower vacancy mobility at the lower temperature. Combined TEM, RBS-C, PAS, and NRA observations highlight increased vacancy mobility and defect recombination with temperature, forming larger vacancy clusters at 800 K. This comprehensive study provides quantitative insights into defect formation and evolution in W single crystals, presenting a comparative analysis of defect distributions across multiple techniques and revealing temperature-dependent mechanisms of microstructural change.
Keywords: heavy-ion irradiation, structural defects
Published in DiRROS: 11.12.2025; Views: 80; Downloads: 41
Full text (9,96 MB)
This document has many files! More...