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This paper is focused on feedback control of postprandial glucose levels for patients with type 1 Diabetes Mellitus. There are two important limitations that make this a challenging problem. First, the slow subcutaneous insulin pharmacokinetics that introduces a significant lag into the control loop. Second, the positivity constraint on the control action, meaning that it is not possible to remove insulin from the body. In this paper, both issues are explicitly considered in the design process using the internal model control framework, to derive a near-optimal feedback controller. Optimality is understood here as minimizing the blood glucose peak after a meal intake and, at the same time, preventing glucose values below a prescribed threshold. It is shown how the proposed controller approaches the optimal closed-loop performance as a limit case. The theoretical results are supported by a numerical example and the feasibility of the overall strategy under uncertainties is illustrated using an extended version UVa/Padova metabolic simulator.

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Fundamento. La precisión diagnóstica de la gammagrafía ósea (GO) aumenta con las imágenes SPECT/TAC haciendo conveniente reevaluar su utilidad diagnóstica en la sacroilitis de la espondiloartritis axial (EA). El objetivo fue comparar el rendimiento diagnóstico de la resonancia magnética (RM), la SPECT/TC y ambas pruebas combinadas, y evaluar la correlación entre los índices cuantitativos de ambas técnicas. Métodos. A 31 pacientes con EA activa y 22 con lumbalgia inflamatoria se les realizó una RM y una SPECT/TC de las articulaciones sacroilíacas y se calculó la precisión diagnóstica de ambas técnicas respecto al diagnóstico clínico. La correlación entre ambas pruebas se calculó comparando los índices de actividad del SPECT/TC con los sistemas de puntuación Berlín y SPARCC de RM. Resultados. Los valores de sensibilidad y especificidad de la SPECT/TC cuantitativa, tomando como punto de corte el cociente sacroilíaca/promontorio >1,36, fueron similares a los publicados para la RM. La combinación de ambas técnicas aumentó la sensibilidad manteniendo una alta especificidad. La correlación entre las escalas totales de RM y SPECT/TC fue moderada y mejoraba al utilizar únicamente las escalas de inflamación. Conclusiones. La SPECT/TC cuantitativa muestra una mejor precisión diagnóstica que la GO planar en la sacroilitis activa y una correlación moderada con las puntuaciones de RM. La combinación de ambas técnicas aumenta la precisión diagnóstica. Por tanto, la SPECT/TAC cuantitativa podría tener un papel relevante en el diagnóstico de sacroilitis en pacientes con alta sospecha de EA y RM negativa/no concluyente o en aquellos pacientes en los que no se pueda realizar una RM.(AU)

Background. The diagnostic accuracy of bone scintigraphy (BS) increases with SPECT/CT imaging. It would therefore be appropriate to reassess the diagnostic utility of scintigraphy in sacroiliitis with axial spondyloarthritis (SpA). The aim of this study was to compare the diagnostic performance of MRI, SPECT/CT and a combination of both techniques in sacroiliitis, and to evaluate the correlation between quantitative SPECT/CT indices and quantitative MRI inflammatory lesion scores. Methods. Thirty-one patients with active SpA and 22 patients with inflammatory low back pain underwent MRI and SPECT/CT of the sacroiliac joints. The diagnostic accuracy of both techniques was calculated using clinical diagnosis as the gold standard. The correlation between MRI and SPECT/CT was calculated by comparing the SPECT/CT activity indices and the Berlin/SPARCC scoring systems for MRI. Results. The sensitivity and specificity values in quantitative SPECT/CT, taking the sacroiliac/promontory ratio of >1.36 as the cut-off value, were close to those from MRI published in the literature. The combination of both techniques increased sensitivity while maintaining high specificity. There was a moderate correlation between SPECT/CT and MRI total scores. This correlation was improved by using solely the MRI inflammation scores. Conclusion. Quantitative SPECT/CT showed better diagnostic accuracy than planar scintigraphy and showed a moderate correlation with MRI scores in active sacroiliitis. The combination of both tests increased the diagnostic accuracy. Quantitative SPECT/CT could play a relevant role in the diagnosis of active sacroiliitis in patients with high a suspicion of SpA and a negative/inconclusive MRI test or in patients with whom MRI studies cannot be carried out.(AU)

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BACKGROUND AND OBJECTIVE: Hybrid automated insulin delivery systems rely on carbohydrate counting to improve postprandial control in type 1 diabetes. However, this is an extra burden on subjects, and it introduces a source of potential errors that could impact control performances. In fact, carbohydrates estimation is challenging, prone to errors, and it is known that subjects sometimes struggle to adhere to this requirement, forgetting to perform this task. A possible solution is the use of automated meal detection algorithms. In this work, we extended a super-twisting-based meal detector suggested in the literature and assessed it on real-life data. METHODS: To reduce the false detections in the original meal detector, we implemented an implicit discretization of the super-twisting and replaced the Euler approximation of the glucose derivative with a Kalman filter. The modified meal detector is retrospectively evaluated in a challenging real-life dataset corresponding to a 2-week trial with 30 subjects using sensor-augmented pump control. The assessment includes an analysis of the nature and riskiness of false detections. RESULTS: The proposed algorithm achieved a recall of 70 [13] % (median [interquartile range]), a precision of 73 [26] %, and had 1.4 [1.4] false positives-per-day. False positives were related to rising glucose conditions, whereas false negatives occurred after calibrations, missing samples, or hypoglycemia treatments. CONCLUSIONS: The proposed algorithm achieves encouraging performance. Although false positives and false negatives were not avoided, they are related to situations with a low risk of hypoglycemia and hyperglycemia, respectively.

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BACKGROUND: The diagnostic accuracy of bone scintigraphy (BS) increases with SPECT/CT imaging. It would therefore be appropriate to reassess the diagnostic utility of scintigraphy in sacroiliitis with axial spondyloarthritis (SpA). The aim of this study was to compare the diagnostic performance of MRI, SPECT/CT and a combination of both techniques in sacro-iliitis, and to evaluate the correlation between quantitative SPECT/CT indices and quantitative MRI inflammatory lesion scores. METHODS: Thirty-one patients with active SpA and 22 patients with inflammatory low back pain underwent MRI and SPECT/CT of the sacroiliac joints. The diagnostic accuracy of both techniques was calculated using clinical diagnosis as the gold standard. The correlation between MRI and SPECT/CT was calculated by comparing the SPECT/CT activity indices and the Berlin/SPARCC scoring systems for MRI. RESULTS: The sensitivity and specificity values in quantitative SPECT/CT, taking the sacroiliac/promontory ratio of >1.36 as the cut-off value, were close to those from MRI published in the literature. The combination of both techniques increased sensitivity while maintaining high specificity. There was a moderate correlation between SPECT/CT and MRI total scores. This correlation was improved by using solely the MRI inflammation scores. CONCLUSION: Quantitative SPECT/CT showed better diagnostic accuracy than planar scintigraphy and showed a moderate correlation with MRI scores in active sacroiliitis. The combination of both tests increased the diagnostic accuracy. Quanti-tative SPECT/CT could play a relevant role in the diagnosis of active sacroiliitis in patients with high a suspicion of SpA and a negative/inconclusive MRI test or in patients with whom MRI studies cannot be carried out.

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The knowledge acquired during university education about organ donation and transplantation (ODT) decisively influences the information future health professionals transmit. This is important in ODT where the participation of the general public is essential to obtain organs. OBJECTIVE: To determine notions of Spanish medicine and nursing students on ODT and its relationship with attitude toward ODT. METHODS AND DESIGN: and design. We conducted a sociologic, multicenter, and observational study. The population for our study consisted of medical and nursing students in Spanish universities. Our database was the Collaborative International Donor Project, stratified by geographic area and academic course. A validated questionnaire (PCID-DTO-RIOS) was self-administered and completed anonymously. Our sample consisted of 9598 medical and 10,566 nursing students (99% confidence interval; precision of ±1%), stratified by geographic area and year of study. RESULTS: The completion rate for our study was 90%. Only 20% (n=3640) of students thought their notions on ODT were good; 41% (n=7531) thought their notions were normal; 36% (n=6550) thought their notions were scarce. Comparing groups, there were differences between those who believed that their notions on ODT were good (44% nursing vs 56% medical students; P < .000), and those who believed it scarce (54% nursing vs 46% medical students; P < .000). Notions on ODT were related with attitude toward the donation of one's own organs: those who considered their notions were good were more in favor then those who considered it scarce (88% vs 72%; P < .000). CONCLUSION: Only 20% of Spanish medical and nursing students thought their notions on ODT were good. Having good knowledge is related to a favorable attitude towards ODT. Receiving specific information on the subject could improve their knowledge about ODT during their training.

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INTRODUCTION: Information provided by health care professionals is crucial to create a climate of social opinion. This is important in organ donation and transplantation (ODT), where the participation of the general public is essential to obtain organs. OBJECTIVE: To determine the attitude toward the Law of Presumed Consent (LPC) among Spanish university students and to analyze their relation with attitude toward ODT. METHODS: and design. The type of study was a sociologic, multicenter, observational study. The population included medical and nursing students in Spanish universities. Database of Collaborative International Donor Project was used stratified by geographic area and academic course. A validated questionnaire (Collaborative International Donor Project, organ donation and transplantation questionnaire in Spanish [PCID-DTO-RIOS]) was self-administered and completed anonymously. A sample of 9598 medical and 10,566 nursing students was analyzed (99% confidence and precision of ±1%) and stratified by geographic area and year of study. RESULTS: Completion rate was 90%. Regarding attitude toward LPC, 66% of the students were against the law, whereas 34% accepted it. Of the students surveyed, 9% considered the law as a gesture of solidarity, 25% as an effective way of not wasting organs, 48% as an abuse of power, and 18% as offenses against the family. Those students who were in favor of LPC also had a more favorable attitude toward ODT (86% vs 76%; P < .001). Comparing groups, nursing students were less in favor of LPC than medical students (32% vs 36%; P < .000). CONCLUSION: Sixty-six percent of Spanish university medical and nursing students were against the LPC. The favorable attitude toward ODT is associated with considering the law as a gesture of solidarity or as an effective way of not wasting organs.

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INTRODUCTION: A favorable attitude toward organ donation and transplantation (ODT) is fundamental among health professionals at the time of transplant promotion. In this sense, the training and awareness of professionals are fundamental. OBJECTIVE: To analyze the differences in the attitude toward ODT and the factors that condition it among Andalusian medical and nursing students. METHODS AND DESIGN: The study is a sociologic, multicenter, observational study. The population includes medical and nursing students in Andalusian universities. Database of the Collaborative International Donor Project is used and data are stratified by geographic area and academic course. The instrument of measurement was a validated questionnaire (PCID-DTO-RIOS) that was handed out to every student in a compulsory session. Completion of the questionnaire was anonymous and self-administered. The sample included Andalusian medical and nursing students (99% confidence and precision of ±1%) stratified by geographic area and year of study. RESULTS: There was a completion rate of 91%; 79% (n = 2879) of Andalusian students were in favor of donation and 21% were not in favor. The attitude toward ODT is more favorable in medical compared with nursing students (80% vs 77%; P = .021). The psychosocial profile toward donation is similar in both groups relating to the following variables (P < .05): knowing a transplant patient, having received information about the subject, attitude toward family donation, and having discussed transplantation with family and friends. CONCLUSION: Andalusian medical students favored organ donation more than Andalusian nursing students, and the favorable attitude is associated with having an awareness of the subject.

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A primary care physician (PCP) not only accompanies the patient in the process of an illness, but throughout his or her life. The confidence we have in these health professionals is fundamental, and their favorable attitude toward organ donation and transplantation (ODT) has a significant influence on the population. OBJECTIVE: To analyze trust in PCPs among Spanish medical and nursing students, the relationship with their attitude toward ODT, and the factors that condition it. METHODS AND DESIGN: A sociologic, multicenter, and observational study. POPULATION: medical and nursing students in Spanish universities. DATABASE: Collaborative International Donor Project, stratified by geographic area and academic course. A validated questionnaire (PCID-DTO-RIOS) was self-administered and completed anonymously. A sample of 9598 medical and 10,566 nursing students (99% confidence and precision of ±1%), stratified by geographic area and year of study. RESULTS: Completion rate: 90%. With respect to students' trust in their physician, 18% (n = 3267) of them totally trust (completely), 45% (n = 8101) trust enough, 30% (n = 5478) of them have not enough trust, and 7% not at all. Comparing groups, medical students totally trust more in PCPs than nursing students (55% vs 45%; P < .000), however, nursing students have less than enough trust in their PCP than medical students (53% vs 47%; P < .000). Students that totally trust in their PCP were more in favor toward ODT than students with not enough trust (83% vs 77%; P < .000). CONCLUSION: Only 18% of Spanish medical and nursing students totally trust in their PCP. Attitude toward ODT is related to a higher level of trust in PCPs among these students.

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INTRODUCTION: Health professionals are asked to promote health, especially organ transplantation; however, they do not always have specific training. OBJECTIVE: To analyze information about donation and organ transplantation among Spanish medical students. METHOD: The population under study is medical students in Spanish universities using the database of the International Donor Collaborative Project, stratified by geographic area and academic year (n = 9275). The instrument used is the attitude questionnaire for organ donation for "PCID-DTO-Ríos" transplantation, validated with an explained variance of 63.203% and α = 0.834. The Student t test was applied together with the χ2 test, complemented by an analysis of the remainders, and Fisher's exact test was applied. RESULTS: Of the students, 74% indicate that they have received information from university professors about organ transplant. Concerning specific issues with the donation, it is notable that only 66.7% (n = 6190) know and accept the concept of brain death as the death of a person. However, only 22% consider themselves as having good information, and 35.3% indicate that their information is scarce or void. Students indicate having received information about transplant from other extra-university sources, such as television and Internet (80.9%), books and magazines (73.2%), and the press (66.9%). From the information obtained in the sociofamilial field, 60.7% have obtained information from the family and 58.1% from friends. Of this information, 9% has been negative from friends, 7.5% from family, 6% from the Internet and television, and 4% from university professors. CONCLUSION: Spanish medical students believe they have little information about organ transplantation and have received negative information.

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INTRODUCTION: Awareness of organ donation among Spanish doctors and medical students is very positive. However, the emerging group of professionals of non-Spanish nationality studying in Spain has not been analyzed. OBJECTIVE: To analyze the differences in the attitudes toward the different types of donation among medical students, according to their nationality. METHODS: The population under study is medical students in Spanish universities using the database of the International Collaborative Donor Project, stratified by geographic area and academic year. Groups under study include students of non-Spanish nationality as group 1 (n = 1570) and students of Spanish nationality as Group 2 (n = 7705). Instruments are validated questionnaires of attitude toward donation "PCID-DTO-Ríos," "PCID-DVR-Ríos," "PCID-DVH-Ríos," and "PCID-XenoTx-Ríos." RESULTS: The attitude toward the donation of own organs after death is similar in both groups (P = .703). Non-Spaniards are 79.2% in favor compared to 79.6% of Spaniards. Living kidney donation, both unrelated (33.3% vs 29.3% in favor; P = .001) and related (91.2% vs 89, 6% in favor; P = .047), is more favorable among non-Spanish students. There are no differences regarding non-related living liver donation (29.7% vs 29.3% in favor; P = .063), but there are differences in the results for related living liver donation (94.1% vs 88%; P < .001). The attitude toward xenotransplantation of organs is similar (80.8% vs 80.8%; P = .999). CONCLUSIONS: Awareness of the donation of organs among Spanish medical students is similar to non-Spanish students studying in Spain, except the attitude toward living donation.

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INTRODUCTION: Despite sensitization of medical students toward the donation of organs, a non-negligible percentage of students are not in favor of donation. OBJECTIVE: To analyze the reasons of Spanish medical students who do not have a favorable attitude toward the donation of their own organs after death. METHOD: The population under study is medical students in Spanish universities, using the database of the International Donor Collaborative Project, stratified by geographic area and academic year. The questionnaire completion was anonymous and self-administered. The study group is medical students with an unfavorable attitude toward organ donation. The assessment instrument used is a validated questionnaire of attitude toward the donation of organs for transplant, "PCID-DTO-Ríos." The reasons against the donation are valued in the questionnaire through a question. RESULTS: Of the participants included in the PCID, students who are not in favor of organ donation were selected (n = 1899). Of them, 8.1% (n = 154) are against and 91.1% (n = 1745) are doubtful. The main reasons indicated are the fear of apparent death in 11.4% of respondents, fear of possible mutilation after donation in 11.1%, and religious reasons in 2.6%. Of those, 6.9% indicate other reasons but do not clearly specify the reasons, using words such as "fear" (2.5%) or "doubts about the process" (4.1%); 66.2% (n = 1257) indicated an "assertive refusal" ("I don't want to express my reasons"). CONCLUSION: Twenty percent of Spanish medical students are not in favor of donating their organs and are not in favor of showing their reasons.

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INTRODUCTION: Religious factors have conditioned the attitude toward organ donation and transplantation (ODT) since the beginning of transplantation, despite the fact that most religions are in favor of transplantation. OBJECTIVE: To assess the impact of religious beliefs of medical students on their attitude toward ODT. METHOD: Population under study: Medical students in Spanish universities. STUDY SAMPLE: Stratified by geographical area and academic course. Assessment instrument: Attitude ODT questionnaire PCID-DTO-Ríos, anonymous and self-administered. RESULTS: Of all students, 42% (n = 3907) declare themselves atheists or agnostics. The remaining 58% (n = 5368) declare themselves to be religious, the majority being Catholic (55%, n = 5102). Of the rest, 0.2% are Muslims (n = 8), 0.1% Protestants (n = 1), and the remaining 2.7% (n = 257) indicate other religious doctrines but do not want to specify it. Regarding their attitude toward ODT, those who consider themselves atheists or agnostics have a more favorable attitude than those who consider themselves religious (84% versus 76%; P < .001). Among those who follow some kind of religion, Catholics are more in favor of ODT than non-Catholics (77% vs 64%, P < .001). Note that among the religious, only 57% (n = 3050) know which religion is in favor of transplantation, while 22% (n = 1,152) consider that it has not been pronounced on the matter, 13% (n = 723) think the religion is against donation, and the remaining 8% (n = 443) do not know. CONCLUSION: The religion professed by medical students conditions their attitude toward donation, with the atheists and agnostics being more in favor of donation.

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The involvement of health professionals from their training period is important for the promotion of living liver donation. There are data that indicate that the awareness of living donation is lower in areas with high rates of deceased donation. OBJECTIVE: To analyze the attitude toward living liver donation among Spanish medical students, according to donation rates of their regions. METHOD: Population under study: Medical students in Spanish universities. Database of the Collaborative International Donor Project, stratified by geographic area and academic course. The completion was anonymous and self-administered. Groups under study: group 1 (n = 1136): students in universities of regions with >50 donors per million population (pmp); group 2 (n = 2018): students in region universities with <40 donors pmp. Assessment instrument: the attitude questionnaire for living liver donation Proyecto Colaborativo Internacional Donante sobre Donación de Vivo Hepático-Ríos (PCID-DVH Ríos). RESULTS: The attitude toward related liver donation is more favorable among the students of regions with <40 donors pmp than among those of >50 donors pmp. Thus, in group 1, a total of 88% (n = 1002) of students are in favor compared with 91% (n = 1831) of group 2 (P=.02). The psychosocial profile of each study group about their attitude toward living related liver donation is analyzed. There is a similar profile between the 2 groups, although there are differences in some variables such as age, a belief that one might need a transplant, family discussion about donation and transplantation, discussion with friends about donation and transplantation, and knowing about a donor. CONCLUSIONS: The awareness of living related donation among Spanish medical students is greater among the regions with lower organ donation rates.

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The awareness of organ donation among health professionals is important at the time of transplant promotion. In this sense, the training and awareness of the professionals in training is fundamental. OBJECTIVE: To analyze the differences in the attitude toward organ donation and the factors that condition it among medical students of regions with donation rates >50 donors per million population (pmp) with respect to those with rates <40 donor pmp. METHOD: Population under study: medical students in Spanish universities. Database of the Collaborative International Donor Project, stratified by geographic area and academic course. The completion was anonymous and self-administered. Groups under study: Group 1 (n = 1136): students in universities of regions with >50 donors pmp. Group 2 (n = 2018): university students in regions with <40 donors pmp. Assessment instrument: attitude questionnaire for organ donation for transplant PCID-DTO-Ríos. RESULTS: The attitude toward organ donation for transplantation is similar among students from the autonomous communities with >50 donors pmp and with <40 donors pmp. In group 1, 79% (n = 897) of students are in favor compared with 81% (n = 1625) of group 2 (P=.29). The psychosocial profile toward donation is similar in both groups relating to the following variables (P < .05): sex, having discussed transplantation with family and as a couple, considering the possibility of needing a transplant, involvement in prosocial activities, attitude toward the manipulation of corpses, knowledge of the brain death concept, and religion. CONCLUSIONS: The awareness of organ donation in Spanish medical students is quite homogeneous and is not related to the local donation rates of each region.

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INTRODUCTION: Medical students represent a new generation of medical thought, and if they have a favourable attitude towards organ donation this will greatly encourage its promotion. OBJECTIVE: To analyse the attitude of medical students in Spanish universities towards the donation of their own organs and to determine the factors affecting this attitude. MATERIAL AND METHODS: Type of study: A sociological, interdisciplinary, multicentre, and observational study in Spain. STUDY POPULATION: Students studying a degree in medicine enrolled in Spain (n = 34,000). SAMPLE SIZE: A sample of 9598 students (confidence of 99% and precision of ±1%), stratified by geographical area and academic year. Instrument of measurement: A validated questionnaire of attitude towards organ donation and transplantation (PCID-DTO RIOS) was self-administered and completed anonymously. RESULTS: The questionnaire completion rate was 95.7% (n = 9.275). 80% were in favour of donation, 2% against and 18% were undecided. The following main variables were related to a favourable attitude: being of the female sex (Odds Ratio = 1.739); being in the sixth year of the degree (OR = 2.506); knowing a donor (OR = 1.346); having spoken about the subject with one's family (OR = 2.132) and friends (OR = 1.333); having a family circle that is in favour, more specifically, having a father (OR = 1.841), mother (OR = 2.538) or partner in favour (OR = 2.192); being a blood donor (OR = 2.824); acceptance of the mutilation of the body if it were necessary (OR = 2.958); and being an atheist or an agnostic (OR = 1.766). CONCLUSIONS: Spanish medical students generally have a favourable attitude towards organ donation, although 20% are not in favour.

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OBJECTIVE: To analyze the level of understanding of the brain death concept among medical students in universities in Spain. METHODS: This cross-sectional sociological, interdisciplinary, and multicenter study was performed on 9598 medical students in Spain. The sample was stratified by geographical area and academic year. A previously validated self-reported measure of brain death knowledge (questionnaire Proyecto Colaborativo Internacional Donante sobre la Donación y Transplante de Organos) was completed anonymously by students. RESULTS: Respondents completed 9275 surveys for a completion rate of 95.7%. Of those, 67% (n = 6190) of the respondents understood the brain death concept. Of the rest, 28% (n = 2652) did not know what it meant, and the remaining 5% (n = 433) believed that it did not mean that the patient was dead. The variables related to a correct understanding of the concept were: (1) being older ( P < .001), (2) studying at a public university ( P < .001), (3) year of medical school ( P < .001), (4) studying at one of the universities in the south of Spain ( P = .003), (5) having discussed donation and transplantation with the family ( P < .001), (6) having spoken to friends about the matter ( P < .001), (7) a partner's favorable attitude toward donation and transplantation ( P < .001), and (8) religious beliefs ( P < .001). CONCLUSIONS: Sixty-seven percent of medical students know the concept of brain death, and knowledge improved as they advanced in their degree.

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INTRODUCTION: The attitude of medical students towards living kidney donation (LKD) is of great interest given that they will become promoters of this technique in the near future. OBJECTIVE: To analyse the attitude of Spanish medical students towards related and unrelated LKD and to determine the factors affecting this attitude. MATERIALS AND METHODS: Type of study: A sociological, interdisciplinary, multicentre, and observational study. STUDY POPULATION: Medical students enrolled in Spain (n = 34.000). SAMPLE SIZE: A sample of 9598 students (99 % confidence and precision of ±1 %), stratified by geographical area and academic year. Measurement instrument: A validated questionnaire (PCID-DVR RIOS) was administered and completed anonymously. RESULTS: There was a completion rate of 95.7 % (n = 9275); 93 % (n = 8630) were in favour of related LKD, and 30 % (n = 2784) were in favour of unrelated LKD. The following factors were associated with this attitude: (1) age (p = 0.008); (2) sex (p < 0.001); (3) year of university degree (p < 0.001); (4) a belief that a transplant might be necessary in the future (p < 0.001); (5) attitude towards deceased organ donation (p < 0.001); (6) a willingness to accept a kidney from a living donor (p < 0.001); (7) attitude towards living liver donation (p < 0.001); (8) a partner's attitude towards donation (p < 0.001); (9) having spoken about the subject with one's family (p < 0.001), or friends (p < 0.001); (10) pro-social behaviour (p < 0.001); (11) the respondent's religious attitude (p < 0.001); and (12) fear of possible mutilation of the body after donation (p < 0.001). CONCLUSIONS: The attitude of medical students towards LKD is very favourable when it is the related kind of donation, and it is associated with factors of general knowledge about organ donation and transplantation and social interaction and religion.

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The artificial pancreas aims at the automatic delivery of insulin for glycemic control in patients with type 1 diabetes, i.e., closed-loop glucose control. One of the challenges of the artificial pancreas is to avoid controller overreaction leading to hypoglycemia, especially in the late postprandial period. In this study, an original proposal based on sliding mode reference conditioning ideas is presented as a way to reduce hypoglycemia events induced by a closed-loop glucose controller. The method is inspired in the intuitive advantages of two-step constrained control algorithms. It acts on the glucose reference sent to the main controller shaping it so as to avoid violating given constraints on the insulin-on-board. Some distinctive features of the proposed strategy are that 1) it provides a safety layer which can be adjusted according to medical criteria; 2) it can be added to closed-loop controllers of any nature; 3) it is robust against sensor failures and overestimated prandial insulin doses; and 4) it can handle nonlinear models. The method is evaluated in silico with the ten adult patients available in the FDA-accepted UVA simulator.

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The behavior of three insulin action and glucose kinetics models was assessed for an insulin therapy regime in the presence of patient variability. For this purpose, postprandial glucose in patients with type 1 diabetes was predicted by considering intra- and inter-patient variability using modal interval analysis. Equations to achieve optimal prediction are presented for models 1, 2 and 3, which are of increasing complexity. The model parameters were adjusted to reflect the "same" patient in the presence of variability. The glucose response envelope for model 1, the simplest insulin-glucose model assessed, included the responses of the other two models when a good fit of the model parameters was achieved. Thus, under variability, simple glucose-insulin models may be sufficient to describe patient dynamics in most situations.

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Considering the difficulty in selecting correct insulin doses and the problem of hyper- and hypoglycemia episodes in type 1 diabetes, dosage-aid systems are very useful for these patients. A model-based approach to this problem must unavoidably consider uncertainty sources such as large intra-patient variability and food intake. In the present study, postprandial glucose is predicted considering this uncertain information using modal interval analysis. This approach calculates a safer prediction of possible hyper- and hypoglycemia episodes induced by insulin therapy for an individual patient's parameters and integrates this information into a dosage-aid system. Predictions of a patient's postprandial glucose at 5-h intervals are used to predict the risk for a given therapy. Then the insulin dose and injection-to-meal time with the lowest risk are calculated. The method has been validated for three different scenarios corresponding to preprandial glucose values of 100, 180 and 250mg/dl.

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