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1.
Retina ; 40(1): 24-32, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30300263

RESUMEN

PURPOSE: To study a prototype of an ultrasound-based vitrector, and to try to understand the physical phenomena underlying this new technology. METHODS: We tested the ultrasound-based vitrector prototype (UV) (ultrasonically-driven handpiece obtained from a modified version of the Alcon CONSTELLATION Vision System [Alcon]) using an automatic experimental setup. Balanced saline solution (BSS) and vitreous (from fresh postmortem enucleated porcine eyes) flow rates were analyzed using three different tips. RESULTS: In general, BSS solution flow rates increased with increasing aspiration levels and decreased when we used % US power. Vitreous flow rates were influenced by aspiration levels, % US power, and ultrasound-related phenomena: cavitation phenomenon and "jet streaming." CONCLUSION: Ultrasound-based vitrectomy may represent an important alternative to traditional vitrectomy. Such a tool, capable of liquefying and excising the vitreous body using ultrasound, could overcome all the limits of the guillotine-based technique (GV). Knowledge of the physical phenomena underlying ultrasound-based technology is a necessary prerequisite for further development of this new technology.


Asunto(s)
Procedimientos Quirúrgicos Ultrasónicos/métodos , Vitrectomía/métodos , Acetatos/metabolismo , Animales , Combinación de Medicamentos , Minerales/metabolismo , Modelos Animales , Cloruro de Sodio/metabolismo , Porcinos , Cuerpo Vítreo/fisiología , Cuerpo Vítreo/cirugía
2.
Radiol Med ; 123(2): 135-142, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28948476

RESUMEN

OBJECTIVES: The early detection of oral soft tissue lesions is an important prognostic factor, and the possibility of using ultrasonography (US) as a diagnostic tool may improve the diagnosis and characterization of tissue alterations at an early stage. This study aims to evaluate the feasibility of intraoral US by performing a preclinical assessment of an ex vivo specimen in which focal lesions were simulated. MATERIALS AND METHODS: Fourteen lesions were simulated on a freshly extracted calf tongue, by introducing in the tongue different materials mimicking the appearance of various focal lesions. The specimen was scanned with a 8 MHz US probe and computed tomography (CT) was performed to compare the two imaging techniques. Later, the specimen was dissected to set a benchmark for size assessment. RESULTS: US was able to identify all the simulated lesions within the tongue, resulting in one case more accurate than CT. Statistical analysis demonstrated high correlation between the measurements of the simulated lesions performed on the US images and the real size of the materials introduced in the tongue (p < 0.05). CONCLUSIONS: This preclinical study proves that US performs well in the detection and characterization of simulated lesions of the tongue. These findings suggest that US could be effectively used in clinical applications. However, further research is mandatory to assess the reliability of in vivo US in the detection and characterization of tongue lesions as well as of other oral soft tissue alterations.


Asunto(s)
Tomografía Computarizada por Rayos X/métodos , Enfermedades de la Lengua/diagnóstico por imagen , Enfermedades de la Lengua/patología , Ultrasonografía/métodos , Animales , Bovinos , Diagnóstico por Computador , Diagnóstico Precoz , Estudios de Factibilidad , Orofaringe/diagnóstico por imagen , Orofaringe/patología , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
3.
Retina ; 37(9): 1765-1774, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27930456

RESUMEN

PURPOSE: Thorough this experimental study, the physic features of a modified 23-gauge vitrectomy probe were evaluated in vitro. METHODS: A modified vitrectomy probe to increase vitreous outflow rate with a small-diameter probe, that also minimized tractional forces on the retina, was created and tested. The "new" probe was created by drilling an opening into the inner duct of a traditional 23-gauge probe with electrochemical or electrodischarge micromachining. Both vitreous outflow and tractional forces on the retina were examined using experimental models of vitreous surgery. RESULTS: The additional opening allowed the modified probe to have a cutting rate of 5,000 cuts per minute, while sustaining an outflow approximately 45% higher than in conventional 23-gauge probes. The modified probe performed two cutting actions per cycle, not one, as in standard probes. Because tractional force is influenced by cutting rate, retinal forces were 2.2 times lower than those observed with traditional cutters. CONCLUSION: The modified probe could be useful in vitreoretinal surgery. It allows for faster vitreous removal while minimizing tractional forces on the retina. Moreover, any available probe can be modified by creating a hole in the inner duct.


Asunto(s)
Retina/fisiología , Vitrectomía/instrumentación , Vitrectomía/métodos , Cuerpo Vítreo/metabolismo , Humanos , Microcirugia/instrumentación , Estrés Mecánico , Tracción
4.
PLoS One ; 19(7): e0305961, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38985717

RESUMEN

PURPOSE: Uncertainty and complexity have increased in recent decades, posing new challenges to humanitarian organisations. This study investigates whether using standard terminology in Human Resource Management processes can support the Humanitarian supply chain in attracting and maintaining highly skilled operators. METHODOLOGY: We exploit text mining to compare job vacancies on ReliefWeb, the reference platform for humanitarian job seekers, and ESCO, the European Classification of Skills, Competencies, and Occupations. We measure the level of alignment in these two resources, providing quantitative evidence about terminology standardisation in job descriptions for supporting HR operators in the Humanitarian field. FINDINGS: The most in-demand skills, besides languages, relate to resource management and economics and finance for capital management. Our results show that job vacancies for managerial and financial profiles are relatively more in line with the European database than those for technical profiles. However, the peculiarities of the humanitarian sector and the lack of standardisation are still a barrier to achieving the desired level of coherence with humanitarian policies.


Asunto(s)
Minería de Datos , Humanos , Perfil Laboral , Altruismo , Selección de Personal , Sistemas de Socorro/economía
5.
PLoS One ; 15(12): e0244175, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33382727

RESUMEN

Covid-19 has rapidly redefined the agenda of technological research and development both for academics and practitioners. If the medical scientific publication system has promptly reacted to this new situation, other domains, particularly in new technologies, struggle to map what is happening in their contexts. The pandemic has created the need for a rapid detection of technological convergence phenomena, but at the same time it has made clear that this task is impossible on the basis of traditional patent and publication indicators. This paper presents a novel methodology to perform a rapid detection of the fast technological convergence phenomenon that is occurring under the pressure of the Covid-19 pandemic. The fast detection has been performed thanks to the use of a novel source: the online blogging platform Medium. We demonstrate that the hybrid structure of this social journalism platform allows a rapid detection of innovation phenomena, unlike other traditional sources. The technological convergence phenomenon has been modelled through a network-based approach, analysing the differences of networks computed during two time periods (pre and post COVID-19). The results led us to discuss the repurposing of technologies regarding "Remote Control", "Remote Working", "Health" and "Remote Learning".


Asunto(s)
Prueba de COVID-19 , COVID-19 , Pandemias , SARS-CoV-2 , Teletrabajo , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/prevención & control , Humanos
6.
Micromachines (Basel) ; 11(12)2020 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-33339146

RESUMEN

Micro polymer parts can be usually manufactured either by conventional injection moulding (IM) or by micro-injection moulding (µIM). In this paper, functional analysis was used as a tool to investigate the performances of IM and µIM used to manufacture the selected industrial component. The methodology decomposed the production cycle phases of the two processes and attributed functions to parts features of the two investigated machines. The output of the analysis was aimed to determine casual chains leading to the final outcome of the process. Experimental validation of the functional analysis was carried out moulding the same micro medical part in thermoplastic elastomer (TPE) material using the two processes by means of multi-cavity moulds. The produced batches were assessed using a precision scale and a high accuracy optical instrument. The measurement results were compared using capability indexes. The data-driven comparison identified and quantified the correlations between machine design and part quality, demonstrating that the µIM machine technology better meets the accuracy and precision requirements typical of micro manufacturing productions.

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