3D CATBraTS: Channel Attention Transformer for Brain Tumour Semantic Segmentation

Brain tumour diagnosis is a challenging task yet crucial for planning treatments to stop or slow the growth of a tumour. In the last decade, there has been a dramatic increase in the use of convolutional neural networks (CNN) for their high performance in the automatic segmentation of tumours in medical images. More recently, Vision Transformer (ViT) has become a central focus of medical imaging for its robustness and efficiency when compared to CNNs. In this paper, we propose a novel 3D transformer named 3D CATBraTS for brain tumour semantic segmentation on magnetic resonance images (MRIs) based on the state-of-the-art Swin transformer with a modified CNN-encoder architecture using residual blocks and a channel attention module. The proposed approach is evaluated on the BraTS 2021 dataset and achieved quantitative measures of the mean Dice similarity coefficient (DSC) that surpasses the current state-of-the-art approaches in the validation phase

Milling cutting tool diagnosis using comparisons of the excitation identified by cepstral techniques

This paper investigates the diagnosis of cutting tools in a milling operation using vibration signals and proposes a signal processing algorithm to achieve that. In the proposed algorithm, the impulse response of the measured vibration signal is firstly identified using the random decrement technique. This is then converted to a cepstrum and subtracted from the measured signal in the quefrency domain using the additive properties of cepstra. The residual signal representing the forcing function is then transformed back into the time domain using the inverse cepstrum. Finally the power spectral density is estimated, and a comparison is made between the different states of the cutting tool. For a good estimation of the force, four measurement points are used, and the identified excitation sources are then averaged. By comparing the spectra of the forcing functions, the efficiency of the method is demonstrated, and the faulty case is clearly distinguished from the fault-free case. This was not the case with the original response signals

Fresh, hardened and durability properties of sodium carbonate-activated Algerian slag exposed to sulfate and acid attacks

This paper investigates the use of Na2CO3 as an alkaline activator on the durability of the alkali-activated slag (AAS) mortar toward sulfates and acids. The behavior of this binder in these aggressive environments is compared to those of slags activated with Na2SiO3 and NaOH. In addition, the setting times, workabilities, mechanical properties and drying shrinkage were evaluated. The AAS had superior workabilities, faster setting times and higher shrinkage rates than the Portland cement (PC). Increases in the activator dosages had positive effects on the mechanical strengths of the materials. Na2SiO3 was the best activator in terms of strength development, but it led to much higher shrinkage. The AAS showed less expansion and lower weight losses than the PC when exposed to sulfate and acids, respectively. The Na2CO3-AAS exhibited less shrinkage and higher resistance to sulfuric acid than the other activators, but the mechanical strength seen at early ages was low

‘The phoenix that always rises from the ashes’: an exploratory qualitative study of the experiences of an initiative informed by principles of psychological first aid following the Beirut blast

BACKGROUND: On 4 August 2020, an explosion occurred in Beirut, Lebanon. Hundreds of people were killed, thousands injured and displaced. An initiative was rapidly initiated to provide remote support informed by psychological first aid for the mental health of Lebanese young adults affected by the blast. However, little is known about recipients’ experiences of such initiatives. OBJECTIVES: This study aimed to qualitatively explore the experiences of supporters and recipients in the community-led initiative following the blast. METHOD: We recruited a diverse sample of four supporters and four Lebanese recipients who took part in the Beirut initiative. Semi-structured interviews were conducted with participants. Reflexive thematic analysis was used to analyse the qualitative data. RESULTS: We developed five themes from the qualitative interviews, which highlighted ideas around accessibility, alienation, the relationship, elements of the safe space created by the initiative, and unmet needs and areas for improvement. Recipients described the detrimental impact of the blast on their mental health within the Lebanese context and beyond. Recipients and supporters elucidated complex experiences of the support and its impact. CONCLUSIONS: Our findings suggest remote support has the potential to be acceptable for young adults in Lebanon. Further research into support informed by psychological first aid after similar crisis events is warranted

Why alternative teenagers self-harm: exploring the link between non-suicidal self-injury, attempted suicide and adolescent identity

Background: The term ‘self-harm’ encompasses both attempted suicide and non-suicidal self-injury (NSSI). Specific adolescent subpopulations such as ethnic or sexual minorities, and more controversially, those who identify as ‘Alternative’ (Goth, Emo) have been proposed as being more likely to self-harm, while other groups such as ‘Jocks’ are linked with protective coping behaviours (for example exercise). NSSI has autonomic (it reduces negative emotions) and social (it communicates distress or facilitates group ‘bonding’) functions. This study explores the links between such aspects of self-harm, primarily NSSI, and youth subculture.<p></p> Methods: An anonymous survey was carried out of 452 15 year old German school students. Measures included: identification with different youth cultures, i.e. Alternative (Goth, Emo, Punk), Nerd (academic) or Jock (athletic); social background, e.g. socioeconomic status; and experience of victimisation. Self-harm (suicide and NSSI) was assessed using Self-harm Behavior Questionnaire and the Functional Assessment of Self-Mutilation (FASM).<p></p> Results: An “Alternative” identity was directly (r ≈ 0.3) and a “Jock” identity inversely (r ≈ -0.1) correlated with self-harm. “Alternative” teenagers self-injured more frequently (NSSI 45.5% vs. 18.8%), repeatedly self-injured, and were 4–8 times more likely to attempt suicide (even after adjusting for social background) than their non-Alternative peers. They were also more likely to self-injure for autonomic, communicative and social reasons than other adolescents.<p></p> Conclusions: About half of ‘Alternative’ adolescents’ self-injure, primarily to regulate emotions and communicate distress. However, a minority self-injure to reinforce their group identity, i.e. ‘To feel more a part of a group’

Optimization of the efficiency in an induction machine drive by algorithm based on the interior point method

[EN] This work optimizes the efficiency of the squirrel cage type Inverter-Induction Machine (IM) system, using an algorithm based on the Interior Point Method (IPM), where the input variables are the electromagnetic torque and the rotor speed at steady state,and as outputs the optimal efficiency and slip values are obtained. The optimum rotor flux value is calculated, which is used as a reference in the flux control loop, in the direct control vector method of the IM. Simulation results are obtained where the increase in efficiency is observed in low load states. The experimental installation used in the implementation of the vector control with maximum system efficiency is described, and the experimental results obtained are shown. A discussion is carried out on the results and the use of the Interior Point Optimization Method.[ES] En este trabajo se realiza la optimización de la eficiencia del sistema  Inversor-Máquina de Inducción (MI) del tipo jaula de ardilla, utilizando un algoritmo basado en el Método de Punto Interior (MPI), donde las variables de entrada son el par electromagnético y la velocidad del rotor en estado estacionario, y como salidas se obtienen los valores de la eficiencia óptima y del deslizamiento. Se calcula el valor del flujo óptimo del rotor que se utiliza como referencia en el lazo de control del flujo, en el control vectorial método directo de la MI. Se obtienen resultados de simulación donde se observa el incremento de la eficiencia en estados de baja carga. Se describe la instalación experimental usada en la implementación del control vectorial con máxima eficiencia del sistema, y se muestran los resultados experimentales obtenidos. Se realiza una discusión sobre los resultados y la utilización del Método de Optimización de Punto Interior.Instituto Politécnico Nacional (IPN), proyecto multidisciplinario registro número 1995.Pacheco-Montiel, J.; Badaoui, M.; Rodríguez-Rivas, J.; Alvarado-Farías, JM.; Carranza-Castillo, O.; Ortega-González, R. (2021). Optimización de la eficiencia en el accionamiento de una máquina de inducción mediante algoritmo basado en el método de punto interior. Revista Iberoamericana de Automática e Informática industrial. 18(4):336-346. https://doi.org/10.4995/riai.2020.13418OJS336346184Andréasson, N., Evgrafov, A., Patriksson, M, 2020. An Introduction to Continuous Optimization Fundations & Fundamental Algorithms. Dover Publications.Benson, H. Y., Shanno, D. F, 2014. Interior-point methods for nonconvex nonlinear programming: cubic regularization. Comput Optim Appl, 58:323-346. https://doi.org/10.1007/s10589-013-9626-8Borisevich, A., and Schullerus, G, 2016. 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E., Duarte, A. Q, 2014. Technical and Economical Considerations on Super High-Efficiency Three-Phase Motors. IEEE Trans. on Ind. App., vol. 50, no. 2, pp. 1274-1285, March/April. https://doi.org/10.1109/TIA.2013.2272548Eftekhari, S. R., Davari, S. A., Naderi, P., García C., Rodriguez, J, 2020. Robust Loss Minimization for Predictive Direct Torque and Flux Control of an Induction Motor With Electrical Circuit Model. IEEE Trans. on Power Electronics, vol. 35, no. 5, pp. 5417-5426, May. https://doi.org/10.1109/TPEL.2019.2944190Farhat, I. A., El-Hawary, M. E, 2009. Interior point methods application in optimum operational scheduling of electric power systems. IET Generation, Transmission & Distribution, vol. 3, Iss. 11, pp. 1020-1029. https://doi.org/10.1049/iet-gtd.2008.0573IEA International Energy Agency. World Energy Outlook, 2018. IEA, Paris 2018. 01/2020. https://www.iea.org/reports/world-energy-outlook-2018.IEC 60034-30-1, 2014. 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Stapling and Section of the Nasogastric Tube during Sleeve Gastrectomy: How to Prevent and Recover?

Bariatric surgery has become an integral part of morbid obesity treatment with well-defined indications. Some complications, specific or not, due to laparoscopic sleeve gastrectomy (LSG) procedure have recently been described. We report a rare complication unpublished to date: a nasogastric section during great gastric curve stapling. A 44-year-old woman suffered of severe obesity (BMI 36.6 kg/m2) with failure of medical treatments for years. According to already published technique, a LSG was performed. Six hours postoperatively, a nurse removed the nasogastric tube according to the local protocol and the nasogastric tube was abnormally short, with staples at its extremity. Surgery was performed with peroperative endoscopy. In conclusion, this is the first publication of a nasogastric section during LSG. Therefore we report this case and propose a solution to prevent its occurrence. To avoid this kind of accident, we now systematically insert the nasogastric tube by mouth through a Guedel cannula. Then, to insert the calibrating bougie, we entirely withdraw the nasogastric tube