1,377 research outputs found

    Designing the physical metallurgy of a bainitic microalloyed steel with a dilatometer

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    During the past decade, medium carbon microalloyed steels have become increasingly important in the automotive sector. These steels are especially suitable for automobile components such as connecting rods, crankshafts and wheel hubs. Their mechanical properties are generally adequate in most cases although their toughnesses are consistently low. High toughness can be obtained in medium carbon microalloyed bainitic steel (38MnV7) after a careful control of the chemistry and heat thermal treatment. An specific chemical composition of a 38MnV7 steel has been developed, providing impact energies after Charpy-V tests at room temperature as high as 40J (the steel in bainitic state). Present work is oriented to an optimization of the above chemical composition by control of the Transformation Time Temperature (TTT) curves as well as the Precipitation Time Temperatures (PTT) curves of the present microallying elements. To attain this purpose six different casting were prepared, ranging the chemical composition as follows %C: 0.35-0.46, %Mn: 1.33-1.84, %V: 0.066-0.14% and %Ti: 0.010- 0.025. To appropriate design the thermal cycle, TTT curves were determined for each steel at two austenitization conditions, in order to promote fine and large initial grain sizes.. PTT curves were determined by the stress relaxation technique, a method which can be also be used to derive recrystrallization kinetics. All curves, TTT and PTT curves where derived by using a quenching dilatometer Bahr DIL805A/D. While the TTT curves were obtained in a classical way, the relaxation test consist in sample austenization followed by cooling down to the testing temperature. After a short stabilization period of 10s, samples are deformed to different strain levels and then relaxed, i.e. deformation is kept constant and the variation of the stress with the time is recorded. The different deformation levels are selected to evaluate the effect of deformation on precipitation characteristics. The relaxation curves under these conditions gave information about the kinetics of precipitation when there is no plastic deformation and, thus, generation of dislocations involved. Results are finally discussed in terms of the chemical composition, initial microstructure and precipitates interaction.Peer Reviewe

    Experiences of mothers of extremely preterm infants after hospital discharge

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    The purpose of this study was to describe and understand the experiences of mothers of extremely preterm infants during the first twelve months at home following discharge from a neonatal intensive care unit. A qualitative, interpretative approach using Gadamer's philosophical hermeneutics was carried out. One focus group and fifteen in-depth, semi-structured interviews were conducted twelve months after hospital discharge. Responses were recorded, transcribed and analyzed using computer-assisted qualitative data analysis. The study´s participants were twenty women. The following themes emerged from the data analysis: 1) 'The journey home: the discharge process', which included the sub-themes 'escaping the hospital environment: between desire and fear' and 'preparing parents for hospital discharge: practice and formal support'; and 2) 'The difficulty of living with an extremely preterm infant', including the sub-themes 'the challenge of an unexpected form of childcare', 'overprotection of and bond with a child with special needs' and 'disturbance in the social/familiar setting: when a mother becomes a nurse'. The process of hospital discharge and the first months at home are difficult. The birth and care of an extremely preterm infant affect the mothers' quality of life as well as their family and social life. Practice and early discharge programmes can make the discharge process easier. The knowledge and understanding of the experience of mothers of extremely preterm infants in the first months at home after hospital discharge could help healthcare professionals to develop educational strategies and counselling interventions in accordance with the mothers' needs. [Abstract copyright: Copyright © 2018 Elsevier Inc. All rights reserved.

    Accompanied child irregular migrants who arrive to Spain in small boats: experiences and health needs

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    The European Union is the preferred destination of child irregular migrants arrived from northern Africa, who risk their lives crossing the Mediterranean Sea in small boats. Accompanied Child Irregular Migrants (AChIMs) are exposed to physical and psychological risk. The objective of our study is to describe and understand the experiences and health needs of AChIMs who arrive to Spain in small boats, through the testimony of adults who accompany them on the journey. A qualitative study, based on Gadamer's hermeneutic phenomenology, was performed. After obtaining approval from the Ethics and Research Committee, we conducted in-depth interviews on 32 adults who travelled with AChIMs. Two main themes emerged: (1) The journey a child should never have to take, with the subthemes 'AChIMs as a paradigm of vulnerability' and 'Crossing the sea, playing with death' and (2) Characterising emergency care to AChIMs, with the subthemes 'Prioritising specific care', 'Identifying high-risk situations' and 'The detaining of innocent children'. AChIMs, along with adults, risk their lives in such a dangerous and perilous journey, therefore, finding out about their experiences may contribute to improving the treatment of their specific health needs during the phases of rescue and emergency care

    Predictor factors of perceived health in family caregivers of people diagnosed with mild or moderate Alzheimer's disease

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    Caring for a person diagnosed with Alzheimer’s disease has a negative impact on family caregivers’ psychological health. This study examined the factors related to ‘perceived health’ and ‘presence of new-onset mental health problems’ in family caregivers of people diagnosed with mild and moderate Alzheimer’s disease. A cross-sectional observational study carried out in Almeria’s Healthcare District (Spain). A total of 255 family caregivers (42.4% cared for people with mild Alzheimer’s disease and 57.6% cared for people with moderate Alzheimer’s disease) participated in the study from January to December 2015. Mainly, caregivers were women (81.5% in the mild Alzheimer’s disease group and 88.4% in the moderate Alzheimer’s disease group), and their average age was 56.54 years (standard deviation (SD) = 13.13) and 54.47 years (SD = 11.71), respectively. Around 47% of the caregivers had been caring for the person with Alzheimer’s between two and five years. The Goldberg General Health Questionnaire was used to measure perceived health and the presence of new-onset mental health problems. An exploratory descriptive analysis and a multivariate logistic regression analysis were conducted. For caregivers of people with mild Alzheimer’s disease, ‘perceived health’ was related to ‘perceived social support’ (r = −0.21; p = 0.028), ‘person’s level of dependency’ (r = −0.24, p = 0.05), ‘severity of the person’s neuropsychiatric symptoms’ (r = 0.22; p = 0.05), and ‘caregiver’s emotional distress in response to the person’s neuropsychiatric symptoms’ (r = 0.22; p = 0.05). For caregivers of people with moderate Alzheimer’s disease, ‘perceived health’ was related to ‘perceived social support’ (r = −0.31; p ˂ 0.01), ‘presence of neuropsychiatric symptoms’ (r = 0.27, p = 0.01), ‘severity of the person’s neuropsychiatric symptoms’ (r = 0.32, p = 0.01) and ‘caregiver’s emotional distress in response to the person’s neuropsychiatric symptoms’ (r = 0.029; p = 0.01). The presence of new-onset mental health problems was detected in 46.3% (n = 50) of caregivers of people with mild Alzheimer’s and 61.9% (n = 91) of caregivers of people with moderate Alzheimer’s. When people are diagnosed with mild Alzheimer’s disease, intervention programs for caregivers should aim to regulate emotions and promote positive coping strategies. When people are diagnosed with moderate Alzheimer’s disease, intervention programs for caregivers must allow them to adapt to caregiving demands that arise with the progression of Alzheimer’s disease

    Design and psychometric evaluation of the 'Clinical Communication Self-Efficacy Toolkit'

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    Nursing students experience difficulties when communicating in clinical practice. Their self-efficacy in clinical communication should be explored as part of their competence assessment before they are exposed to real human interactions in the clinical setting. The aim of this study was to design and psychometrically evaluate a toolkit to comprehensively assess nursing students’ self-efficacy in clinical communication. The study followed an observational cross-sectional design. A sample of 365 nursing students participated in the study. The ‘Clinical Communication Self-Efficacy Toolkit’ (CC-SET) was comprised of three tools: the ‘Patient-Centered Communication Self-efficacy Scale’ (PCC-SES), the ‘Patient clinical Information Exchange and interprofessional communication Self-Efficacy Scale’ (PIE-SES), and the ‘Intrapersonal communication and Self-Reflection Self-Efficacy Scale’ (ISR-SES). The tools’ reliability, validity (content, criterion, and construct) and usability were rigorously tested. The Cronbach’s alpha coefficient of the three tools comprising the CC-SET was very high and demonstrated their excellent reliability (PCC-SES = 0.93; PIE-SES = 0.87; ISR-SES = 0.86). The three tools evidenced to have excellent content validity (scales’ content validity index > 0.95) and very good criterion validity. Construct validity analysis demonstrated that the PCC-SES, PIE-SES, and ISR-SES have a clear and theoretically-congruent structure. The CC-SET is a comprehensive toolkit that allows the assessment of nursing students’ self-efficacy in interpersonal, interprofessional, and intrapersonal communication

    FIRST REPORT OF USE OF LAND SNAILS FOR HETEROMYS GAUMERI (RODENTIA: HETEROMYIDAE) IN A SUBDECIDUOUS FOREST IN YUCATÁN, MÉXICO

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    Se presenta el primer registro de uso de caracoles terrestres por Heteromys gaumeri en la selva mediana subcaducifolia localizada en el Rancho Hobonil, Tzucacab, Yucatán, México. Siete por ciento de la población total (n= 789) de H. gaumeri usó caracoles que habitan en el área. Las especies fueron: Choanopoma largillierti y C. gaigei (Annulariidae), Neocyclotus dysoni (Cyclophoridae) y Drymaeus shattucki (Bulimulidae). Cincuenta y uno por ciento de las muestras de los roedores fueron hembras y el 49% machos. Los adultos representaron el 86% y los juveniles 14%. El uso de caracoles tuvo relación significativa entre sexos de los roedores y la estacionalidad (p< 0.01). Los caracoles fueron usados con mayor frecuencia en la estación de sequía por las hembras y por los machos adultos y juveniles en la de lluvias. Treinta y cinco por ciento de las hembras de la muestra que usaron caracoles estaban preñadas o lactantes. El género Choanopoma fue el más abundante y removido por H. gaumeri en ambas estaciones, mientras que Neocyclotus lo fue en la de lluvias y D. shattucki se encontró rara vez. Por lo observado consideramos que este ratón además de semillas come caracoles terrestres en esta región

    Design and psychometric analysis of the COVID-19 prevention, recognition and home-management self-efficacy scale

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    In order to control the spread of COVID-19, people must adopt preventive behaviours that can affect their day-to-day life. People’s self-efficacy to adopt preventive behaviours to avoid COVID-19 contagion and spread should be studied. The aim of this study was to develop and psychometrically test the COVID-19 prevention, detection, and home-management self-efficacy scale (COVID-19-SES). We conducted an observational cross-sectional study. Six-hundred and seventy-eight people participated in the study. Data were collected between March and May 2020. The COVID-19-SES’ validity (content, criterion, and construct), reliability (internal consistency and test-retest reliability), and legibility were studied. The COVID-19-SES’ reliability was high (Cronbach’s alpha = 0.906; intraclass correlation coefficient = 0.754). The COVID-19-SES showed good content validity (scale’s content validity index = 0.92) and good criterion validity when the participants’ results on the COVID-19-SES were compared to their general self-efficacy (r = 0.38; p 0.001). Construct validity analysis revealed that the COVID-19-SES’ three-factor structure explained 52.12% of the variance found and it was congruent with the World Health Organisation’s recommendations to prevent COVID-19 contagion and spread. Legibility analysis showed that the COVID-19-SES is easy to read and understand by laypeople. The COVID-19-SES is a psychometrically robust instrument that allows for a valid and reliable assessment of people’s self-efficacy in preventing, detecting symptoms, and home-managing COVID-19

    Experience of parents who have suffered a perinatal death in two Spanish hospitals: a qualitative study

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    Background: Perinatal grief is a process that affects families in biological, psychological, social and spiritual terms. It is estimated that every year there are 2.7 million perinatal deaths worldwide and 4.43 deaths for every 1000 births in Spain. The aim of this study is to describe and understand the experiences and perceptions of parents who have suffered a perinatal death. Methods: A qualitative study based on Gadamer’s hermeneutic phenomenology. The study was conducted in two hospitals in the South of Spain. Thirteen mothers and eight fathers who had suffered a perinatal death in the 5 years prior to the study participated in this study. In-depth interviews were carried out for data collection. Inductive analysis was used to find themes based on the data. Results: Eight sub-themes emerged, and they were grouped into three main themes: ‘Perceiving the threat and anticipating the baby’s death: “Something is going wrong in my pregnancy”’; ‘Emotional outpouring: the shock of losing a baby and the pain of giving birth to a stillborn baby’; “We have had a baby”: The need to give an identity to the baby and legitimise grief’. Conclusion: The grief suffered after a perinatal death begins with the anticipation of the death, which relates to the mother’s medical history, symptoms and premonitions. The confirmation of the death leads to emotional shock, characterised by pain and suffering. The chance to take part in mourning rituals and give the baby the identity of a deceased baby may help in the grieving and bereavement process. Having empathy for the parents and notifying them of the death straightaway can help ease the pain. Midwives can help in the grieving process by facilitating the farewell rituals, accompanying the family, helping in honouring the memory of the baby, and supporting parents in giving the deceased infant an identity that makes them a family member
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