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Abstract Background The purpose was to evaluate the clinical effect of a custom-made Y-shaped fracture fragment reduction device and to assist in posterior unilateral small fenestration of lamina to reduce the fracture fragments. Methods In this study, 40 patients were assigned to one of two groups: the traditional reduction device group (TRG) or the Y-shaped reduction device group (YRG). All patients underwent posterior unilateral small fenestration of the lamina and direct decompression through the spinal canal. And the operation time (OT), intraoperative bleeding (IB), preoperative, postoperative, and final follow-up data on the spinal stenosis rate (SSR), Cobb angle, the anterior compression ratio of injured vertebrae (ACRIV), and ASIA neurological function grade were compared between the two groups. Result There were no complications, including vascular and nerve injury, serious postoperative infection, internal fixation fracture, or loosening, for any of the patients. And the average follow-up time of the two groups was 14.2 months, the average operation time of the TRG was 236.6 min, and the average intraoperative blood loss was 357.20 ml. Moreover, the average operation time of the YRG was 190.6 min, and the average intraoperative blood loss was 241.5 ml. There were significant differences between the two groups in terms of operation duration and intraoperative blood loss. The YRG's was lower than that of the TRG. Besides, there was no difference in SSR, Cobb angle, ACRIV, or neurological recovery between the two groups before or immediately after the operation or at the last follow-up. Conclusion The Y-shaped fracture reduction device can reduce the fracture fragments and the OT and IB stably; it also has satisfactory postoperative curative effects and clinical utility.

Background: The purpose was to evaluate the clinical effect of a custom-made Y-shaped fracture fragment reduction device and to assist in posterior unilateral small fenestration of lamina to reduce the fracture fragments. Methods: In this study, 40 patients were assigned to one of two groups: the traditional reduction device group (TRG) or the Y-shaped reduction device group (YRG). All patients underwent posterior unilateral small fenestration of the lamina and direct decompression through the spinal canal. And the operation time (OT), intraoperative bleeding (IB), preoperative, postoperative, and final follow-up data on the spinal stenosis rate (SSR), Cobb angle, the anterior compression ratio of injured vertebrae (ACRIV), and ASIA neurological function grade were compared between the two groups. Result: There were no complications, including vascular and nerve injury, serious postoperative infection, internal fixation fracture, or loosening, for any of the patients. And the average follow-up time of the two groups was 14.2 months, the average operation time of the TRG was 236.6 min, and the average intraoperative blood loss was 357.20 ml. Moreover, the average operation time of the YRG was 190.6 min, and the average intraoperative blood loss was 241.5 ml. There were significant differences between the two groups in terms of operation duration and intraoperative blood loss. The YRG's was lower than that of the TRG. Besides, there was no difference in SSR, Cobb angle, ACRIV, or neurological recovery between the two groups before or immediately after the operation or at the last follow-up. Conclusion: The Y-shaped fracture reduction device can reduce the fracture fragments and the OT and IB stably; it also has satisfactory postoperative curative effects and clinical utility. [ABSTRACT FROM AUTHOR]

The aim of the reduction process is to concentrate nickel at high temperatures with a certain carbonaceous material as a reducing agent. The use of chemicals like Na2SO4 and NaCl in the reduction process can increase the content and recovery of nickel in ferronickel concentrates. A selective reduction of laterite nickel was carried out in a non-isothermal and an isothermal using palm kernel shell charcoal as a reductant and with Na2SO4 and NaCl as additives. Firstly, the raw material is made into a pellet and dried in an oven at 100 °C for two hours. The pellets are weighed before and after the reduction process. The non-isothermal reduction process used the Thermal Gravimetric Analysis (TGA) method from a temperature of 100 to 1300 °C, with a heat rate of 10 °C per minute. The isothermal reduction at temperatures 500, 600, 700, 950, 1050, and 1150 °C occurred with a reduction time of 30, 60, and 90 minutes. The analysis is Inductively Coupled Plasma (ICP) to determine the content of nickel and iron from the reduction process, X-ray Diffraction (XRD) to see changes in the phases formed after the selective reduction process, and Scanning Electron Microscopy (SEM-EDX) for viewing the microstructure of the phase. The Differential Thermal Analyzer-Temperature Gravimetric Analysis (DTA-TGA) results show the endothermic at 256 °C, and the exothermic peak at 935 °C with a total mass loss of 42.15% at 1238 °C. The shrinking core model was used for the kinetic studies of the reduction process. The closest kinetic model to the experimental results is the Ginstling-Brounshtein model, with an activation energy value of 8.73 kcal/mol. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The paper deals with design and computation of precise positioning mechanism. The aim of mechanism is to transfer applied load without any change of position of parts in question. The stabilization of position is assured by elastic elements connected to reductor which is adjusted into correct position by an actuator. The functionality of mechanism and its stiffness and strength characteristics were checked by the finite element method. The computations were accomplished for prescribed displacement of reductor. On the base of this type of loading the behaviour of the structure was evaluated.

The aim of the reduction process is to concentrate nickel at high temperatures with a certain carbonaceous material as a reducing agent. The use of chemicals like Na2SO4 and NaCl in the reduction process can increase the content and recovery of nickel in ferronickel concentrates. A selective reduction of laterite nickel was carried out in a non-isothermal and an isothermal using palm kernel shell charcoal as a reductant and with Na2SO4 and NaCl as additives. Firstly, the raw material is made into a pellet and dried in an oven at 100 °C for two hours. The pellets are weighed before and after the reduction process. The non-isothermal reduction process used the Thermal Gravimetric Analysis (TGA) method from a temperature of 100 to 1300 °C, with a heat rate of 10 °C per minute. The isothermal reduction at temperatures 500, 600, 700, 950, 1050, and 1150 °C occurred with a reduction time of 30, 60, and 90 minutes. The analysis is Inductively Coupled Plasma (ICP) to determine the content of nickel and iron from the reduction process, X-ray Diffraction (XRD) to see changes in the phases formed after the selective reduction process, and Scanning Electron Microscopy (SEM-EDX) for viewing the microstructure of the phase. The Differential Thermal Analyzer-Temperature Gravimetric Analysis (DTA-TGA) results show the endothermic at 256 °C, and the exothermic peak at 935 °C with a total mass loss of 42.15% at 1238 °C. The shrinking core model was used for the kinetic studies of the reduction process. The closest kinetic model to the experimental results is the Ginstling-Brounshtein model, with an activation energy value of 8.73 kcal/mol. [ABSTRACT FROM AUTHOR]

Es este artículo se presenta la implementación de un semáforo preventivo de dos caras con leds de alta luiniscencia color amarillo, el cual se instala en onas escolares como una alternativa para disminuir la accidentalidad que se presenta en éstas, dado que los últimos reportes de accidentalidad de la Secretaria de Tránsito y Transporte del año 2006 muestran que un 35% de los accidentes ocurren en las afueras de los colegios. El sistema tiene adaptado en su interior una fuente switchada en modo Step-down (reductor); además un subsistema de control que trabaja de tal forma que hace que el semáforo funcione con 60 destellos por minuto alternados para las dos caras. Este semáforo ofrece 880.35 lumens más de luminosidad y un ahorro de 83,45% energía en comparación con el semáforo convencional de bombillo incandescente; logrando así que incursionemos en el área de la optoelectrónica para obtener nuevas aplicaciones dentro del sector productivo.