RESUMEN
The consumer market has changed drastically in recent times. Consumers are becoming more demanding, and many companies are competing to be market leaders. Therefore, companies must reduce rejects and minimize their operating costs. One problem that arises in producing plastic parts is controlling deformation, mainly in the form of shrinkage due to the material and warpage associated with the geometry of the parts. This work presents a novel extended adaptive weighted sum method (EAAWSM: Extended Adaptive Weighted Summation Method) integrated into a Pareto front model. The performance of this model is evaluated against three other conventional optimization methods-Taguchi-Gray (TG), Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), and Model Optimization by Genetic Algorithm (MOGA)-and compared with EAAWSM. Two response variables and three input factors are considered to be analyzed: material melting temperature, mold temperature, and filling time. Subsequently, the performance is compared and its behavior observed using Moldflow® simulation. The results show that with the EAAWSM method, the shrinkage is 15.75% and the warpage is 3.847 mm, regarding the manufacturing process parameters of a plastic part. This proposed deterministic model is easy to use to optimize two or more output variables, and its results are straightforward and reliable.
RESUMEN
Introducción: La hemodiálisis continúa siendo la modalidad de terapia de reemplazo renal prevalente en el mundo. La disfunción de la fístula arteriovenosa para hemodiálisis tiene efectos negativos en el paciente y su calidad de vida, por lo que el acceso vascular funcional se necesita para un adecuado tratamiento de hemodiálisis en pacientes con enfermedad renal terminal. El mayor inconveniente del acceso vascular resulta su alta incidencia de oclusión trombótica, causada por la estenosis, la cual se inicia por lesiones hiperplásicas de la capa intimal del vaso. Una de las modalidades de tratamiento a nivel internacional es la trombólisis del acceso vascular trombosado de menos de 24 horas de evolución. Objetivo: Exponer los resultados obtenidos con la aplicación de la trombólisis percutánea del acceso vascular para hemodiálisis trombosado en paciente con enfermedad renal terminal. Presentación del caso: Paciente masculino de 52 años, con diagnóstico de trombosis aguda del acceso vascular para hemodiálisis por enfermedad renal terminal, de 5 días de evolución, con deterioro de su estado de salud por encontrarse subdializado y urémico, con agotamiento del acceso vascular global para hemodiálisis. Se utilizó el tratamiento fibrinolítico directo del acceso vascular percutáneo a 100 mil UI/hora de Heberquinasa® en 10 horas, con recuperación del latido, thrill y repermeabilización de la fístula para hemodiálisis. Conclusiones: El tratamiento fibrinolítico con Heberquinasa® permitió la recuperación del paciente con trombosis aguda del acceso vascular para hemodiálisis. Se evitaron complicaciones asociadas a la subdiálisis y/o colocación de catéter central, y se incorporó al paciente a su programa de hemodiálisis, con garantías para su calidad de vida(AU)
Introduction: Hemodialysis continues to be the prevalent renal replacement therapy modality in the world. Arteriovenous fistula dysfunction for hemodialysis has negative effects on the patients and their quality of life, so functional vascular access is needed for adequate hemodialysis treatment in patients with end-stage renal disease. The greatest drawback of vascular access is its high incidence of thrombotic occlusion, caused by stenosis, which is initiated by hyperplastic lesions of the intimate layer of the vessel. One of the treatment modalities at the international level is the thrombolysis of the thrombosed vascular access of less than 24 hours of evolution. Objective: To present the results obtained with the application of percutaneous thrombolysis of vascular access for thrombosed hemodialysis in patients with end-stage renal disease. Case presentation: Male patient of 52 years, with diagnosis of acute thrombosis of vascular access for hemodialysis due to end-stage renal disease, 5 days of evolution, with deterioration of his health state due to being sub-dialized and uremic, with exhaustion of the global vascular access for hemodialysis. Direct fibrinolytic treatment of percutaneous vascular access at 100 thousand IU/hour of Heberkinase® was used in 10 hours, with recovery of the heartbeat, thrill and repermeabilisation of the fistula for hemodialysis. Conclusions: Fibrinolytic treatment with Heberkinase® allowed the recovery of the patient with acute thrombosis from the vascular access for hemodialysis. Complications associated with sub-dialysis and/or central catheter placement were avoided, and the patient was incorporated into their hemodialysis program, with guarantees for their quality of life(AU)
Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Diálisis Renal/métodosRESUMEN
Advances in tissue engineering have made possible the construction of organs and tissues with the use of biomaterials and cells. Three important elements are considered: a specific cell culture, an adequate environment, and a scaffold. The present study aimed to develop P3HB scaffolds by 3D printing and evaluate their biocompatibility with HaCaT epidermal cells, as a potential model that allows the formation of functional tissue. By using a method of extraction and purification with ethanol and acetone, a biopolymer having suitable properties for use as a tissue support was obtained. This polymer exhibited a higher molecular weight (1500 kDa) and lower contact angle (less than 90°) compared to the material obtained using the conventional method. The biocompatibility analysis reveals that the scaffold obtained using the ethanol-acetone method and produced by 3D printing without pores was not cytotoxic, did not self-degrade, and allowed high homogenous cell proliferation of HaCaT cells. In summary, it is possible to conclude that the P3HB scaffold obtained by 3D printing and a simplified extraction method is a suitable support for the homogeneous development of HaCaT keratinocyte cell lineage, which would allow the evaluation of this material to be used as a biomatrix for tissue engineering.
RESUMEN
Introducción: Las oclusiones arteriales periféricas agudas de menos de 14 días y de causa embólica y trombótica están asociadas a una alta morbimortalidad. La trombólisis dirigida por catéter representa en la actualidad una modalidad de tratamiento efectivo para la oclusión de vasos distales infrageniculares, que históricamente ha tenido malos resultados mediante embolectomía convencional, debido a la oclusión preexistente de vasos colaterales y al daño mecánico al endotelio, que conlleva esta técnica tradicional. Se decidió presentar este caso por ser la primera vez que se practica esta modalidad de tratamiento en Cuba. Objetivo: Exponer los resultados obtenidos con la aplicación de la trombolisis fibrinolitica mediante catéter en un paciente afectado por trombosis arterial periférica aguda. Presentación del caso: Paciente masculino de 57 años de edad con diagnóstico de trombosis arterial aguda de la arteria poplítea del miembro inferior izquierdo, con más de 24 horas de evolución de la isquemia y del compromiso de la viabilidad de la extremidad. Se utilizó el tratamiento fibrinolítico, mediante infusión de 250 000 unidades de Heberkinasa® en tres horas y se logró la mejoría del nivel de amputación. Conclusiones: El tratamiento fibrinolítico con Heberkinasa® fue útil en el paciente tratado porque redujo el nivel de amputación en el paciente, que presentó isquemia irreversible y criterio inicial de amputación supracondílea alto, en la extremidad comprometida(AU)
Introduction: Acute peripheral arterial occlusions of less than 14 days and of embolic and thrombotic cause are associated with a high morbidity and mortality. Catheter-directed thrombolysis currently represents an effective treatment modality for the occlusion of infragenicular distal vessels, which has historically had poor results by conventional embolectomy, due to the pre-existing occlusion of collateral vessels and the mechanical damage to the endothelium, which this traditional technique entails. It was decided to present this case because it is the first time that this modality of treatment is practiced in Cuba. Objective: Present the results obtained with the application of fibrinolytic thrombolysis by catheter in a patient affected by acute peripheral arterial thrombosis. Case presentation: A 57-year-old male patient diagnosed with acute arterial thrombosis of the popliteal artery of the left lower limb, with more than 24 hours of evolution of ischemia and compromised viability of the limb. Fibrinolytic treatment was used, by infusion of 250,000 units of Heberkinase® in three hours and the improvement of the amputation level was achieved. Conclusions: Fibrinolytic treatment with Heberkinase® was useful in the treated patient because it reduced the level of amputation in the patient, who presented irreversible ischemia and initial criteria of high supracondylar amputation in the compromised limb(AU)
Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Trombosis de las Arterias Carótidas/diagnóstico , Embolectomía/métodosRESUMEN
A new type of field practice which is being carried out by the School of Public Health of the National University of Colombia as part of a training program for health visitors and inspectors, is described and an evaluation is made of the results. The reasons for the change, as well as the changes made, are indicated. An outline is given of the planning and execution of these practical exercises, which consist essentially of an environmental sanitation program conducted by the students, under teacher supervision, and with the participation of the community benefited. The results are analyzed from the teaching viewpoint, and in relation to the construction of sanitary works. A comparison is made between the costs and the proportion of program goals attained. Finally, after some general comments the following main conclusions are drawn: 1. The program succeeded in fully achieving all the teaching objectives. 2. The objectives were achieved to a satisfactory degree, as can be seen by the following percentages attained: a. Water supply, 62.4 percent of the proposed objective; b. Sewage disposal, 74.8 percent as compared with the proposed 80 percent; c. Garbage disposal, 100 percent of the objective established; d. Literacy, 75 percent of the proposed goal. 3. The communities covered by this program were organized in such manner that they may be expected to continue to work independently toward their own improvement. 4. Program expenditures for both teaching and application are low. 5. The experiment in concentrating the resources on limited
Asunto(s)
Saneamiento/educación , Salud Ambiental/educación , Capacitación en Servicio , Salud Ambiental , Curriculum , Escuelas de Salud Pública , Ingeniería Sanitaria/educación , ColombiaRESUMEN
A new type of field practice which is being carried out by the School of Public Health of the National University of Colombia as part of a training program for health visitors and inspectors, is described and an evaluation is made of the results. The reasons for the change, as well as the changes made, are indicated. An outline is given of the planning and execution of these practical exercises, which consist essentially of an environmental sanitation program conducted by the students, under teacher supervision, and with the participation of the community benefited. The results are analyzed from the teaching viewpoint, and in relation to the construction of sanitary works. A comparison is made between the costs and the proportion of program goals attained. Finally, after some general comments the following main conclusions are drawn: 1. The program succeeded in fully achieving all the teaching objectives. 2. The objectives were achieved to a satisfactory degree, as can be seen by the following percentages attained: a. Water supply, 62.4 percent of the proposed objective; b. Sewage disposal, 74.8 percent as compared with the proposed 80 percent; c. Garbage disposal, 100 percent of the objective established; d. Literacy, 75 percent of the proposed goal. 3. The communities covered by this program were organized in such manner that they may be expected to continue to work independently toward their own improvement. 4. Program expenditures for both teaching and application are low. 5. The experiment in concentrating the resources on limited
