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1.
J Paediatr Child Health ; 58(10): 1792-1796, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35778914

RESUMEN

AIM: Constipation is one of the most common complaints in childhood affecting the quality of life of both children and parents. This study intends to investigate rectal measurements on ultrasound and their relationship with bowel habits. METHODS: In this cross-sectional study, 100 children with functional constipation (FC) referred to a single hospital between 2018 and 2019 were enrolled. After obtaining informed consent, a questionnaire including demographic and constipation characteristics was completed, and a physical examination including digital rectal examination (DRE) was performed. Complete abdominopelvic ultrasound was then performed. Target measurements included rectal transverse diameter (RTD), rectal anterior wall thickness (RAWT) and the presence of faecal impaction. RESULTS: One hundred children with a mean age of 7.68 ± 3.30 years were present in the study. The mean duration of constipation was 15.86 ± 13.34 months. In 14% of children, painful defaecation was reported. 88% of children had some degree of faecal incontinence. According to the ultrasound findings, the mean RTD and RAWT were 3.39 ± 0.73 cm and 2.77 ± 0.68 mm, respectively, and faecal impaction was present in 70% of cases. There was a positive correlation between RTD and RAWT with age, duration of constipation and the presence of hard stools, and there was a negative correlation with frequency of defecation (P < 0.05). CONCLUSION: RTD and RAWT increased with increasing constipation duration and the presence of hard stools and decreased with increasing frequency of defaecation. DRE could be omitted from the initial clinical assessment if you had access to reliable ultrasound data.


Asunto(s)
Impactación Fecal , Niño , Preescolar , Estreñimiento/diagnóstico por imagen , Estudios Transversales , Defecación , Impactación Fecal/diagnóstico por imagen , Hábitos , Humanos , Calidad de Vida
2.
J Microsc ; 281(3): 190-201, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32926411

RESUMEN

Till now electron microscopy techniques have not been used to evaluate the plasma-target interactions undergone during the magnetron sputtering process. The destructive nature of this interaction severely alters the target microstructure. Utilising quantitative microscopy techniques can shed light on the complex plasma and solid-state processes involved which can ultimately lead to improved functional thin film deposition. As a representative functional material, aluminium-doped-zinc oxide (AZO) is an upcoming alternative to conventional transparent electrode wherein the process optimisation is of great importance. In this paper, we evaluate the pre- and post-sputter field emission scanning electron microscopy (FESEM) data for ceramic AZO target fabricated at three final sintering temperatures (1100°C, 1200°C and 1300°C). In all cases, grain boundaries are merged in addition to a visible reduction in the secondary phases which makes segmentation-based image analysis challenging. Through surface statistics (i.e. fractal dimension, autocorrelation length, texture aspect ratio and entropy) as a function of magnification we can quantify the electron microscopy image of the microstructure. We show that the plasma-microstructure interaction leads to an increase in autocorrelation length, texture aspect ratio and entropy for the optimum AZO ceramic sputtering target sintered at 1200°C. Furthermore, a maximum reduction in fractal dimension span (as determined by exponential regression) is also observed for 1200°C. In addition to the evaluation of plasma effects on sintering, our approach can provide a window towards understanding the underlying thin film growth mechanisms. We believe that this technique can be applied to the defect characterisation of a wide range of polycrystalline ceramic sputtering targets (e.g. ITO, CZTS, GAZO and so on) with the ultimate goal of improving the magnetron sputtering process and the resulting functional thin film. LAY DESCRIPTION: Magnetron sputtering allows scientists to make functional thin films on the order of the nanoscale. In this technique, atoms are plucked from a 'target' then placed onto a substrate forming a thin nanometric film: all thanks to magnets, a special power supply and the fourth state of matter (plasma). Understanding what is going on and how to make a 'good' thin film is important for making better light emitting diodes, solar cells and light sensors. Scientists use electron microscopy to see what is going on in the microstructure of the sputtered thin films to fine tune the sputtering recipe. Here, for the first time, we have applied electron microscopy to see the surface of the microstructure before and after magnetron sputtering. This will help us understanding the plasma-microstructure interaction allowing us to make more informed decisions when fine-tuning the sputtering process to get improved thin films. This is a case study of aluminium-doped zinc oxide (AZO) target that could potentially replace indium tin oxide (ITO), which is widely used as a transparent electrode in devices involving light and electricity. In this case, improved characteristics would be lower electrical resistivity and higher transmission of light. We show that it is possible to use a mathematical description (e.g. the fractal dimension) of the scanning electron microscopy picture to show a link between the target surface and the functional properties. Simple explanation of fractal dimensions by Sixty Symbols ○ https://www.youtube.com/watch?v=cmBljeC79Ls Experimental demonstration of magnetron sputtering by The Thought Emporium ○ https://www.youtube.com/watch?v=Cyu7etM-0Ko Introductory video on magnetron sputtering by Applied Science ○ https://www.youtube.com/watch?v=9OEz_e9C4KM Demonstration of AZO target fabrication and sputtering by Pradhyut Rajjkumar ○ https://www.youtube.com/watch?v=kTLaTJfNX3c Simple explanation of a DIY SEM by Applied Science ○ https://www.youtube.com/watch?v=VdjYVF4a6iU.

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