http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
NEW PROCEDURE TO ESTIMATE THE BRAKE WARPING IN A ROLLER TESTER
D. GARCÍA-POZUELO RAMOS,A. GAUCHÍA,B. L. BOADA,V. DÍAZ 한국자동차공학회 2010 International journal of automotive technology Vol.11 No.5
Vehicle systems such as the steering, brakes and suspension greatly influence vehicle safety. Therefore, these systems must be inspected to guarantee that they are functioning correctly and to certify that the vehicle is functioning at a satisfactory safety level. In disc brakes, warping is one of the principal reasons for vibrations and noise, and it contributes to diminished brake efficiency. Currently, the International Motor Vehicle Inspection Committee (CITA) demands disc brake warping inspections occur during periodic motor vehicle inspections (PMVIs); however, the procedure to carry out this inspection is not well defined. In this investigation, the warping phenomenon has been analyzed, and a new inspection procedure is proposed.
The Role of Mitochondrial Dynamic Dysfunction in Age-Associated Type 2 Diabetes
Vezza Teresa,Díaz-Pozo Pedro,Canet Francisco,de Marañón Aranzazu M.,Abad-Jiménez Zaida,García-Gargallo Celia,Roldan Ildefonso,Solá Eva,Bañuls Celia,López-Domènech Sandra,Rocha Milagros,Víctor Víctor M 대한남성과학회 2022 The World Journal of Men's Health Vol.40 No.3
Mitochondrial dynamics, such as fusion and fission, play a critical role in maintaining cellular metabolic homeostasis. The molecular mechanisms underlying these processes include fusion proteins (Mitofusin 1 [MFN1], Mitofusin 2 [MFN2], and optic atrophy 1 [OPA1]) and fission mediators (mitochondrial fission 1 [FIS1] and dynamin-related protein 1 [DRP1]), which interact with each other to ensure mitochondrial quality control. Interestingly, defects in these proteins can lead to the loss of mitochondrial DNA (mtDNA) integrity, impairment of mitochondrial function, a severe alteration of mitochondrial morphology, and eventually cell death. Emerging evidence has revealed a causal relationship between dysregulation of mitochondria dynamics and age-associated type 2 diabetes, a metabolic disease whose rates have reached an alarming epidemic-like level with the majority of cases (59%) recorded in men aged 65 and over. In this sense, fragmentation of mitochondrial networks is often associated with defects in cellular energy production and increased apoptosis, leading, in turn, to excessive reactive oxygen species release, mitochondrial dysfunction, and metabolic alterations, which can ultimately contribute to β-cell dysfunction and insulin resistance. The present review discusses the processes of mitochondrial fusion and fission and their dysfunction in type 2 diabetes, with special attention given to the therapeutic potential of targeting mitochondrial dynamics in this complex metabolic disorder.
Complications and local relapse after intraoperative low-voltage X-ray radiotherapy in breast cancer
Ana Alicia Tejera Hernández,Víctor Manuel Vega Benítez,Juan Carlos Rocca Cardenas,Neith Ortega Pérez,Nieves Rodriguez Ibarria,Juan Carlos Díaz Chico,Juan José García-Granados Alayón,Pedro Pérez Correa 대한외과학회 2020 Annals of Surgical Treatment and Research(ASRT) Vol.98 No.6
Purpose: To study those factors that influence the occurrence of surgical complications and local relapse in patients intervened for breast cancer and receiving intraoperative radiotherapy. Methods: Observational study on patients intervened for breast cancer with conservative surgery and intraoperative radiotherapy with low-voltage X-ray energy source (INTRABEAM), from 2015 to 2017 with 24 months minimum followup. Variables possibly associated to the occurrence of postoperative complications were analyzed with the Student t-test and the Fisher exact test; P < 0.05 considered significant. Subsequently, the construction of multiple multivariate analysis models began, thus building a logistic regression analysis using the IBM SPSS Statistics ver. 23 software. Local relapse was described. Results: The study included 102 patients, mean age of 61.2 years; mean global size of tumor, 12.2 mm. Complications occurred in 29.4%. Fibrosis was the most frequently observed complication, followed by postoperative seroma. Using a 45 mm or larger applicator were significantly associated with the occurrence of complications. Tumor size 2 cm or larger and reintervention showed borderline significant association. Only one case of local relapse was observed. Conclusion: Certain factors may increase the risk of complication after the use of intraoperative radiotherapy. Using external complementary radiotherapy does not seem to increase the rate of complications. Select patients and the involvement of a multidisciplinary team are essential for achieving good results
Decellularization and In Vivo Recellularization of Abdominal Porcine Fascial Tissue
Sánchez Julio C.,Díaz Diana M.,Sánchez Leidy V.,Valencia-Vásquez Aníbal,Quintero Juan F.,Muñoz Laura V.,Bernal Andrés F.,Osorio Germán,Guerra Álvaro,Buitrago Juliana 한국조직공학과 재생의학회 2021 조직공학과 재생의학 Vol.18 No.3
BACKGROUND: Tissue decellularization has evolved as a promising approach for tissue engineering applications. METHODS: In this study, we harvested fascial tissue from porcine anterior abdominal wall and the samples were decellularized with a combination of agents such as Triton X-100, trypsin and DNAase. Afterwards, we evaluated cell removal by histological analysis and DNA quantification. Mechanical functionality was evaluated by applying a range of hydrostatic pressures. A sample of decellularized fascia was transplanted into a rabbit and after 15 days a biopsy of this tissue was examined; the animal was observed during 6 months after surgery. RESULTS: The extracellular matrix was retained with a complete decellularization as evidenced by histologic examination. The DNA content was significantly reduced. The scaffold preserved its tensile mechanical properties. The graft was incorporated into a full thickness defect made in the rabbit abdominal wall. This tissue was infiltrated by granulation and inflammatory cells and the histologic structure was preserved 15 days after surgery. The animal did not develop hernias, infections or other complications, after a 6-months of follow up. CONCLUSIONS: The protocol of decellularization of fascial tissue employed in this study proved to be efficient. The mechanical test demonstrated that the samples were not damaged and maintained its physical characteristics; clinical evolution of the rabbit, recipient of the decellularized fascia, demonstrated that the graft was effective as a replacement of native tissue.In conclusion, a biological scaffold derived from porcine fascial tissue may be a suitable candidate for tissue engineering applications. BACKGROUND: Tissue decellularization has evolved as a promising approach for tissue engineering applications. METHODS: In this study, we harvested fascial tissue from porcine anterior abdominal wall and the samples were decellularized with a combination of agents such as Triton X-100, trypsin and DNAase. Afterwards, we evaluated cell removal by histological analysis and DNA quantification. Mechanical functionality was evaluated by applying a range of hydrostatic pressures. A sample of decellularized fascia was transplanted into a rabbit and after 15 days a biopsy of this tissue was examined; the animal was observed during 6 months after surgery. RESULTS: The extracellular matrix was retained with a complete decellularization as evidenced by histologic examination. The DNA content was significantly reduced. The scaffold preserved its tensile mechanical properties. The graft was incorporated into a full thickness defect made in the rabbit abdominal wall. This tissue was infiltrated by granulation and inflammatory cells and the histologic structure was preserved 15 days after surgery. The animal did not develop hernias, infections or other complications, after a 6-months of follow up. CONCLUSIONS: The protocol of decellularization of fascial tissue employed in this study proved to be efficient. The mechanical test demonstrated that the samples were not damaged and maintained its physical characteristics; clinical evolution of the rabbit, recipient of the decellularized fascia, demonstrated that the graft was effective as a replacement of native tissue.In conclusion, a biological scaffold derived from porcine fascial tissue may be a suitable candidate for tissue engineering applications.
Mario Acosta-Flores,Marta Lilia Eraña-Díaz,Eusebio Jiménez-López,Juan Carlos García,Juan José Delfín-Vázquez,Baldomero Lucero-Velázquez 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.7
In this study, a novel method for determining stresses in the torsion problems of laminated composite trimetallic and bimetallic bars was developed and evaluated via experimental and numerical analyses. The objective of this method is to transform a real transversal section of a model for a laminated composite bar into a hypothetical virtual section that is homogenous and isotropic. An analogy with the transformed-section method for solving composite beams under flexion was conducted. The shear stresses (maximum on external surfaces and interfaces) in laminated composite bars were undergoing torsion. Isotropic symmetric and asymmetric laminated composite bars were examined analytically, and the results of their respective experimental and numerical tests were analyzed. The proposed method exhibits differences between 2 % and 12 % compared with the experimental results and between 2 % and 10 % compared with the results obtained using the finite element method.
A. GAUCHÍA,E. OLMEDA,M. J. L. BOADA,B. L. BOADA,V. DÍAZ 한국자동차공학회 2014 International journal of automotive technology Vol.15 No.3
Engineering bus design requires testing of bus structures prototypes in order to guarantee a certain level ofstrength and an appropriate static and dynamic behavior of the bus superstructure when exposed to road loads. However,experimental testing of real bus structures is very expensive as it requires expensive resources and space. If testing is done ona scale bus model the previous required expenses are considerably reduced. Therefore, a novel methodology based ondimensional analysis applied to bus structure prediction to evaluate the bus structure static and dynamic performance isproposed. The static performance is evaluated attending to torsion stiffness and the dynamic in terms of the natural vibrationfrequencies and rollover threshold. A scale bus has been manufactured and dimensionless parameters have been defined inorder to project the results obtained in the scale bus model to a larger model. Validation of the proposed methodology has beencarried out under experimental and finite element analysis.
Kostov, V. B.,McCullough, P. R.,Hinse, T. C.,Tsvetanov, Z. I.,Hé,brard, G.,Dí,az, R. F.,Deleuil, M.,Valenti, J. A. IOP Publishing 2013 The Astrophysical journal Vol.770 No.1
<P>We report the discovery of a transiting, gas giant circumbinary planet orbiting the eclipsing binary KIC 4862625 and describe our independent discovery of the two transiting planets orbiting Kepler-47. We describe a simple and semi-automated procedure for identifying individual transits in light curves and present our follow-up measurements of the two circumbinary systems. For the KIC 4862625 system, the 0.52 +/- 0.018 R-Jupiter radius planet revolves every similar to 138 days and occults the 1.47 +/- 0.08 M-circle dot, 1.7 +/- 0.06 R-circle dot F8 IV primary star producing aperiodic transits of variable durations commensurate with the configuration of the eclipsing binary star. Our best-fit model indicates the orbit has a semi-major axis of 0.64 AU and is slightly eccentric, e = 0.1. For the Kepler-47 system, we confirm the results of Orosz et al. Modulations in the radial velocity of KIC 4862625A are measured both spectroscopically and photometrically, i.e., via Doppler boosting, and produce similar results.</P>