Journal articles: 'Damage to the turbo'

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Xu, Xiao-lei, and Zhi-wei Yu. "Investigation of damage features of a turbo-disk." Engineering Failure Analysis 16, no. 5 (July 2009): 1554–61. http://dx.doi.org/10.1016/j.engfailanal.2008.10.010.

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Martin, Lynn M., Ratnakar Tripathi, Praveen Balne, James Landreneau, Sabeeh Kamil, Suneel Gupta, Nathan P. Hesemann, et al. "Turbo Eye Drops Restore Sulfur Mustard-Induced Corneal Damage." Toxicology Letters 331 (October 2020): 19. http://dx.doi.org/10.1016/j.toxlet.2020.05.071.

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Chen, Dongchao, Yuhao Zhang, and Yujiong Gu. "Online Evaluation of Turbo-Generator Shaft Fatigue Damage Caused by Subsynchronous Oscillation." IEEE Access 8 (2020): 55342–53. http://dx.doi.org/10.1109/access.2020.2981509.

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Gu, Yu Jiong, and Tie Zheng Jin. "Analysis on Torsional Fatigue Life of Turbo-Generator Shafts." Key Engineering Materials 467-469 (February 2011): 1858–63. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.1858.

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Both low-cycle fatigue and high-cycle fatigue exist during torsional vibrations, but the impact of high-cycle fatigue has rarely been considered. In this paper, a torsional fatigue life analyzing method used for torsional vibration of turbo-generator shafts has been developed based on Manson-Coffin equation and high-cycle fatigue theory. The method has been used to estimate the torsional fatigue life in the most dangerous section of the shafts in a power plant. The cumulative torsional fatigue damage under two-phase short circuit simulation has been predicted.

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Zhang, Rong Pei. "Vibration Characteristics and Damage of Turbine Generator Shaft Rubbing." Applied Mechanics and Materials 697 (November 2014): 210–13. http://dx.doi.org/10.4028/www.scientific.net/amm.697.210.

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An abnormal journal vibration occurred when a 660MW turbo generator unit was in daily operation. It was identified that rubbing vibration had taken place based on the behavior of the journal vibration and the temperature change of lubricating oil. The rubbing was located inside the bearing box between the HIP rotor and the LP rotor. However, no elimination measures had been taken in time because the damage caused by rubbing was underestimated. Few months later a full inspection revealed that the LP rotor shaft had been worn out with a 70mm wide and 28mm deep groove, which greatly weakened the strength of the LP rotor. The analysis presented here may help in diagnosing and understanding rubbing-vibration-related problems in similar situations.

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Kreischer, Christian. "Modern methods to monitor end winding vibrations in turbo-generators." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 38, no. 4 (July 1, 2019): 1214–23. http://dx.doi.org/10.1108/compel-10-2018-0403.

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Purpose Problems caused by end winding vibrations in power plant generators have become increasingly evident in recent years and reveal a need for monitoring and diagnostic systems. An increasing number of operational outages are caused by failures of the winding insulation or the conductor itself due to end winding vibrations. Meanwhile, it is clear that the condition of the end winding must be continuously monitored during operation to detect ineffective end winding support in time and to plan the repair. Design/methodology/approach In this paper, the complex and nonlinear excitation mechanisms in large machines are presented and modern methods for vibration monitoring are described. Through a consistent use of vibration monitoring in the end winding area as well as the vibration diagnosis done by experts, damage mechanisms can be detected at an early stage, repair measures can be planned and serious damage owing to a weakened main insulation can be avoided. Findings By combining modal analysis and trend monitoring in relation to the learned vibration behaviour, the end winding condition can be assessed in a differentiated manner and changes in the end winding structure can be detected early. Originality/value Finally, an assessment for a two-pole, air-cooled turbo generator is proposed.

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Gan, Hui, Kun Yu Yang, and Xiao Liang Yang. "Analysis of Structure Characteristics and Improvement of Turbo-Supercharger Bearing." Applied Mechanics and Materials 496-500 (January 2014): 707–10. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.707.

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The reliability of the gas turbo-supercharger can be affected by the faults such as the cauterization of the floating bearing of the supercharger, the carbonization of the rotor and getting stuck, the deformation of the blade and heat cracking of the nozzle ring. The design scheme is proposed by using friction bearing taking the place of the floating bearing, because the main reason of the cauterization of the bearing is the increase of the inside clearance of the floating sleeve, which is testified by the actual rpm measurement of the floating sleeve on the floating bearing and the adjustment test of the inside and outside clearances of the bearing. The experimental study on the structural characteristics of turbocharger bearing effectively prevents turbo-supercharger floating bearing from being cauterized, solves the problem of thermal fatigue damage, and improves turbocharger reliability.

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Dziendzikowski, Michal, Krzysztof Dragan, Artur Kurnyta, Sylwester Klysz, and Andrzej Leski. "Health Monitoring of the Aircraft Structure during a Full Scale Fatigue Test with Use of an Active Piezoelectric Sensor Network." Solid State Phenomena 220-221 (January 2015): 328–32. http://dx.doi.org/10.4028/www.scientific.net/ssp.220-221.328.

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The paper presents an approach to develop a system for fatigue crack growth monitoring and early damage detection in the PZL – 130 ORLIK TC II turbo-prop military trainer aircraft structure. The system functioning is based on elastic waves propagation excited in the structure by piezoelectric PZT transducers. In the paper, a built block approach for the system design, signal processing as well as damage detection is presented. Description of damage detection capabilities are delivered in the paper and some issues concerning the proposed signal processing methods and their application to crack growth estimation models are discussed. Selected preliminary results obtained during the Full Scale Fatigue Test thus far are also presented.

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Dragan, Krzysztof, Michal Dziendzikowski, and Tadeusz Uhl. "The Development of the Non-Parametric Classification Models for the Damage Monitoring on the Example of the ORLIK Aircraft Structure." Key Engineering Materials 518 (July 2012): 358–63. http://dx.doi.org/10.4028/www.scientific.net/kem.518.358.

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This paper presents approach for the damage growth monitoring and early damage detection in the PZL-130 ORLIK TC II turbo propeller military trainer based on the array of the PZT sensors which will be deployed in the structure of the aircraft. Special attention will be paid to the preliminary results of the statistical models which provide an automated tool to infer about the damage presence and its size. In particular the effectiveness of the selected signal characteristics will be assessed using dimensional reduction methods (PCA) and the so called averaged damage indices will be described. Verification of the several classification models based on the emerged damage indices will be presented using cross validation techniques. The preliminary results of the data collected from the subcomponents tests with the model description, as well as approach for the SHM system design will be delivered. The verification of the models results will be presented on the example of the aerospace structures.

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Xu, Xiao-lei, and Zhi-wei Yu. "Damage Features of Bolts Connecting Main-Shaft with Turbo-Disk Used in a Locomotive Turbocharger." Journal of Failure Analysis and Prevention 9, no. 4 (May 12, 2009): 380–84. http://dx.doi.org/10.1007/s11668-009-9258-6.

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Grabovskii, Vladimir. "Torsional Vibrations of the Steam Turbine Shaft Line and Estimation of the Residual Life of Its Elements." Известия высших учебных заведений. Электромеханика 63, no. 6 (2020): 91–98. http://dx.doi.org/10.17213/0136-3360-2020-5-91-98.

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A comparative quantitative assessment of the damage and residual life of the shaft line elements for differ-ent types of high-power steam turbines at the end of their design life is made by mathematical modeling. The analysis covers all elements of the shaft line: from the steam turbine Central pump to the turbine generator ex-citer. The simulated circuit includes turbo generators, transformers, gate converters, AC and DC power lines. When modeling, an approach is used from the position of proper coordinates, which provides maximum meth-odological consistency of the models of the listed devices and allows you to directly reproduce electromagnetic and mechanical transients with the determination of instantaneous values of currents, voltages, electromagnet-ic and torsional moments. To estimate damage, we used the deformation criterion for soft and hard loads in the zone of low-cycle and force criterion in the zone of multi-cycle fatigue. The influence of the number of starts and running time of a steam turbine on the damage and residual life of its shaft elements is studied. When de-termining the remaining life, in addition to starts, other abnormal operating modes of the turbo generator were taken into account during the turbine operating time: short circuits and their disconnections, unsuccessful high-speed automatic re-activation, subsynchronous resonance due to both the operation of the control system of the PPT and the automatic generator excitation regulator. The influence of attenuation of electromagnetic transients in the generator and damping of torsional vibrations on the degree of reduction of the residual life of the shaft elements is analyzed. The results obtained can be used for a comprehensive solution of the issue of further operation of steam turbines that have spent their design life.

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Isakov, Andrei N., Andrei V. Andrusich, and Igor E. Savraev. "Device for Reduction Sparking of Slip Ring of Turbo Generator." Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 2 (August 8, 2015): 116. http://dx.doi.org/10.17770/etr2013vol2.851.

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Most modern power plants generating electric power equipped with synchronous generators. The correct operation of energy economy depends on reliability of such electrical machines. In this article issue of increasing reliability of turbo generator by increasing reliability of its brush contact unit is considered. Description of brush contact unit and its possible damages is given. Equivalent electrical circuit of contact layer of brush contact unit is performed. The equations are formed and the dynamical simulation model consisting of electric source and two brush contact units is created. With help of this model alternative method of improving parameters of brush contact unit and increasing reliability of turbo generator at once is calculated and shown. The implementation of the proposed method of increasing the turbo generator brush contact units reliability can have different technical performance, but the principle laid down in the method remains the same.

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Lesaffre, N., Jean Jacques Sinou, and F. Thouverez. "Stability Analysis of a Flexible Bladed-Rotor." Key Engineering Materials 293-294 (September 2005): 409–16. http://dx.doi.org/10.4028/www.scientific.net/kem.293-294.409.

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In any high-performance turbo-machinery, instability and damage are commonly occurring problems. The aim of this paper is to present a stability analysis of a fully-bladed flexible rotor. The flexural vibrations of the blades as well as those of the shaft are considered; the energetic approach used includes the effect of the rotational inertia. A stability detection method, bringing loci separation phenomena and coalescence, in case of an asymmetric rotor, to the fore, is made in order to determine a parametric domain where turbomachinery cannot encounter damage. Moreover, extensive parametric studies including for instance the length and the stagger angle of the blades are presented in order to obtain robust criteria for stable and unstable areas prediction. Finally, rotor/stator contact is introduced and the effect of the radial load acting on the blades when rubbing against a casing is considered.

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Szczepankowski, Andrzej, Janusz Szymczak, and Jaroslaw Spychała. "Operating Degradations of Air Turbine Scoops of Turbo-Engines." Solid State Phenomena 147-149 (January 2009): 524–29. http://dx.doi.org/10.4028/www.scientific.net/ssp.147-149.524.

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The paper presents various types of turbine scoops damages that are being found in the operating process of air turbine engines (TSO). When dividing them, having in mind a genesis of their origin, a special attention has been paid to corrosion and high-temperature erosion, often being a reason for destruction of the entire unit. The damages hereto described have been illustrated with examples collected during endoscope surveys of TSO internal spaces or their post-failure disassembly. The summary points out to the ways and directions of works aiming at early detection of TSO turbines units damages, and thus at improvement of their operating safety.

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Dragan, Krzysztof, Michal Dziendzikowski, Tadeusz Uhl, and Tadeusz Stepinski. "Remote Monitoring of Fatigue Cracks Growth in the Aircraft Structure Based on Active Piezosensor Network during the Full Scale Fatigue Test." Key Engineering Materials 588 (October 2013): 249–56. http://dx.doi.org/10.4028/www.scientific.net/kem.588.249.

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One of the major issues from a structural integrity point of view of the aircraft structure is an appropriate health monitoring technology delivery for the damage tolerant philosophy. This paper presents a development of a system for fatigue crack growth monitoring and early damage detection in the PZL 130 ORLIK TC II turbo-prop military trainer aft structure. The maintenance system of the aircraft shifts from the safe-life to the hard-time. The aircraft started Full Scale Fatigue Test (FSFT) which will continue up to 2013. In the article a built block approach for the system design, signal modeling, sensing and signal processing as well as damage detection is presented. Taking into the consideration a previous experience of AGH as well as AFIT, a network of PZT transducers was deployed in the aircraft structure hot-spots. The system components are: remote monitoring unit, signal analysis, graphical user interface, sensor self-diagnostic tools, and data classification model. Description of damage detection capabilities are delivered in the paper. In particular some issues concerning the proposed damage indices and its application to crack growth estimation models are discussed. Fishers Linear Discriminant is used as a method to obtain effective crack growth predictors and one of the self-diagnostic tools used in the system. The results of the data collected from specimen fatigue tests are delivered and cross-validation technique is used to evaluate a classification model based on the damage indices derived.

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Dieleman, Nikki, Anja G. van der Kolk, Jaco JM Zwanenburg, Manon Brundel, Anita A. Harteveld, Geert J. Biessels, Fredy Visser, Peter R. Luijten, and Jeroen Hendrikse. "Relations between location and type of intracranial atherosclerosis and parenchymal damage." Journal of Cerebral Blood Flow & Metabolism 36, no. 7 (November 11, 2015): 1271–80. http://dx.doi.org/10.1177/0271678x15616401.

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The aim of this study was to assess the relation between location and type of intracranial atherosclerosis (ICAS) and cortical microinfarcts (CMIs) and macroinfarcts in 18 patients presenting with ischemic stroke ( n = 12) or transient ischemic attack (TIA) ( n = 6) using 7 tesla MR imaging. The protocol included: 3D T2-weighted FLAIR and 3D T1-weighted Magnetization-Preparation Inversion Recovery Turbo Spin Echo sequence. ICAS lesions and infarcts were scored by two raters. The relation between ICAS lesions, calculated ratios of ICAS lesion characteristics, location, and infarcts were examined using linear regression analyses. A total number of 75 ICAS lesions (all patients), 101 CMIs (78% of patients), and 31 macroinfarcts (67% of patients) were found. Seventy-six and sixty-five percent of the CMIs and macroinfarcts, respectively, were found in the same vascular territory as the ICAS lesions ( p = 0.977, p = 0.167, respectively). A positive correlation existed between the number of macroinfarcts and CMIs ( p < 0.05). In patients with macroinfarcts, we found more concentric ( p < 0.01) and diffuse ( p < 0.05) type of ICAS lesions. A high prevalence of brain tissue lesions, both macroinfarcts and CMIs, were found in patients with ICAS. Macroinfarcts were found to be related to specific ICAS lesion types. The type of ICAS lesion seems to be promising as a marker for ICAS patients at higher risk of future infarcts.

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Rovaris, M., E. Judica, A. Ceccarelli, A. Ghezzi, V. Martinelli, G. Comi, and M. Filippi. "Absence of diffuse cervical cord tissue damage in early, non-disabling relapsing-remitting MS: a preliminary study." Multiple Sclerosis Journal 14, no. 6 (July 2008): 853–56. http://dx.doi.org/10.1177/1352458507088103.

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Background Magnetization transfer (MT) magnetic resonance imaging (MRI) can provide quantitative information about the severity of tissue damage in the cervical cord of patients with multiple sclerosis (MS). MT MRI-derived measures of cord damage are correlated with the severity of disease-related locomotor disability. Objectives The objective of this study was to investigate whether MT MRI-detectable cervical cord damage is present in early relapsing-remitting (RR) MS. Subjects and methods We studied 23 patients with ‘early’ RR MS (i.e., with a disease duration shorter than 5 years) and 10 age-matched healthy control subjects. During a single session, the following sequences were acquired using a 1.5 T scanner: (a) brain dual-echo turbo spin echo; (b) cervical cord fast short-tau inversion recovery; (c) cervical cord gradient echo, without and with MT pulse. Brain T2 lesion volume was measured. Cervical cord lesions were counted and normalized histograms of cord MT ratio (MTR) were produced. Results One or more cervical cord lesions were found in nine patients (39%). The average cord MTR and the mean histogram peak height values did not differ between patients and controls. There was no significant correlation between brain T2 lesion volume and cervical cord MTR histogram-derived metrics. Conclusions Cervical cord tissue damage seems to be limited to macroscopic lesions in patients with early, non-disabling RR MS. Longitudinal studies are warranted to define the dynamics of MS-related cord damage accumulation over time later on in the course of the disease.

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Dragan, Krzysztof, Michał Dziendzikowski, Andrzej Leski, Ziemowit Dworakowski, and Tadeusz Uhl. "An Approach to Damage Detection in the Aircraft Structure with the Use of Integrated Sensors – The Symost Project." Fatigue of Aircraft Structures 2012, no. 4 (December 1, 2012): 10–16. http://dx.doi.org/10.2478/v10164-012-0052-7.

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Abstract This paper presents an approach to damage growth monitoring and early damage detection in the structure of PZL - 130 ORLIK TC II turbo-prop military trainer aft using the statistical models elaborated by the Polish Air Force Institute of Technology (AFIT) and the network of the sensors attached to the structure. Drawing on the previous experiences of the AFIT and AGH in structural health monitoring, the present research will deploy an array of the PZT sensors in the structure of the PZL -130 Orlik TC II aircraft. The aircraft has just started Full Scale Fatigue Test (FSFT) that will continue up to 2013. The FSFT of the structure is necessary as a consequence of the structure modification and the change of the maintenance system - the transition to Condition Based Maintenance. In this paper, a novel approach to the monitoring of the aircraft hot-spots will be presented. Special attention will be paid to the preliminary results of the statistical models that provide an automated tool to infer about the presence of damage and its size. In particular, the effectiveness of the selected signal characteristics will be assessed using dimensional reduction methods (PCA) and the so-called averaged damage indices will be delivered. Moreover, the results of the signal classification based on the neural network will be presented alongside the numerical model of the wave propagation. The work contains selected information about the project scope and the results achieved at the preliminary stage of the project

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Hesketh, J. A., and P. J. Walker. "Effects of Wetness in Steam Turbines." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 219, no. 12 (December 1, 2005): 1301–14. http://dx.doi.org/10.1243/095440605x32110.

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Courses in mechanical engineering usually introduce the theory of axial-flow turbo-machines in terms of simple velocity triangles representing the bulk flow of ideal compressible fluid through the blade passages. A distinctive practical difference, peculiar to steam turbines (ST), is the presence of liquid-water in the flow field. The steam wetness in such turbines is widely known to be doubly-damaging, leading to both loss of efficiency and to mechanical damage (erosion, etc.) of the machine components. Over recent decades, a whole new field of mechanical engineering science has evolved on the subject of wetness in steam turbines, and general practices have been established within the industry. This article reviews the general effects that are of major importance to the turbine designer/engineer, power plant operator, and especially to researchers in this field.

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Wang, Lian Yong, and Chao Liu. "Pressure Recovery and Cascade Utilization of Energy in the Process of Natural Gas Transportation." Applied Mechanics and Materials 675-677 (October 2014): 1517–20. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.1517.

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Natural gas is generally transported with high pressure, and most of the gas pressure is above 10MPa, which will be 0.4MPa after the vacuum treatment at pressure regulating station. So there is huge pressure energy that can be recovered. The research uses turbo expander instead of throttle valve in the natural gas transport process, which will avoid the threat and damage to the equipment and lower network by the low temperature natural gas. The huge demand for natural gas pipeline in China makes the research of “pressure recovery and cascade utilization of energy in the process of natural gas transportation” to be true. The research can not only avoid the huge waste of pressure in the network, but it can also improve the comprehensive utilization rate of energy, which is of vital importance to our conservation-oriented society today.

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Abe, Y., Y. Yamashita, Y. Tang, T. Namimoto, Y. Nakayama, and M. Takahashi. "Spin-echo echo-planar MR imaging of hepatocellular carcinoma arising from chronic liver damage: comparison with turbo spin-echo imaging." Computerized Medical Imaging and Graphics 24, no. 1 (February 2000): 43–48. http://dx.doi.org/10.1016/s0895-6111(99)00037-3.

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Uhlmann, Eckart, and Florian Heitmüller. "Improving Efficiency in Robot Assisted Belt Grinding of High Performance Materials." Advanced Materials Research 907 (April 2014): 139–49. http://dx.doi.org/10.4028/www.scientific.net/amr.907.139.

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In gas turbines and turbo jet engines, high performance materials such as nickel-based alloys are widely used for blades and vanes. In the case of repair, finishing of complex turbine blades made of high performance materials is carried out predominantly manually. The repair process is therefore quite time consuming. And the costs of presently available repair strategies, especially for integrated parts, are high, due to the individual process planning and great amount of manually performed work steps. Moreover, there are severe risks of partial damage during manually conducted repair. All that leads to the fact that economy of scale effects remain widely unused for repair tasks, although the piece number of components to be repaired is increasing significantly. In the future, a persistent automation of the repair process chain should be achieved by developing adaptive robot assisted finishing strategies. The goal of this research is to use the automation potential for repair tasks by developing a technology that enables industrial robots to re-contour turbine blades via force controlled belt grinding.

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Aubourg, Santiago P., Hugo Lago, and Javier Pena. "Effect of slaughtering conditions on lipid damage of chilled farmed turbot (Psetta maxima) muscle." Grasas y Aceites 61, no. 3 (April 29, 2010): 312–20. http://dx.doi.org/10.3989/gya.123009.

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Jeong, Jinyong, Intaek Lee, and Junghoon Joo. "A Destruction Pattern Analysis of a Turbo-Molecular Pump According to the Foreline Clamp Damage in an ICP Dry Etcher for 300 mm Wafers." Applied Science and Convergence Technology 24, no. 2 (March 30, 2015): 27–32. http://dx.doi.org/10.5757/asct.2015.24.2.27.

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Cummings, D. O., and J. E. Williamson. "The role of herbivory and fouling on the invasive green alga Caulerpa filiformis in temperate Australian waters." Marine and Freshwater Research 59, no. 4 (2008): 279. http://dx.doi.org/10.1071/mf06238.

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The green macroalga Caulerpa filiformis is rapidly dominating algal assemblages in shallow subtidal regions along the New South Wales (NSW) coast. Given that invasive species are known for their competitive superiority, the interactions between C. filiformis and herbivores and fouling species was investigated and were compared with those co-occurring native species. Extensive field surveys were carried out to assess purported damage from herbivores, and co-occurrence of C. filiformis with herbivorous fish and invertebrate species. Signs of herbivory on C. filiformis were visible, and several common herbivorous invertebrates and fish co-occurred with the alga. Laboratory and field feeding assays with fresh algae indicated that generalist invertebrate herbivores such as Turbo torquatus did not consume C. filiformis, whereas herbivorous fish did consume C. filiformis but not in preference to other palatable algae. C. filiformis was fouled at similar concentrations and with similar epiphytic species to other co-occurring algae. Thus the ability of C. filiformis to deter herbivory and fouling by using biotic deterrents (both chemical and structural) is limited and unlikely to be the major factor driving its successful invasion into NSW habitats.

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Goldsweig, Andrew M., Faisal Hasan, and Carlos Mena. "Tools of the Trade: Adjunctive Tools for Lesion Crossing in Critical Limb Ischemia." Medical Equipment Insights 6 (January 2015): MEI.S18479. http://dx.doi.org/10.4137/mei.s18479.

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Critical limb ischemia (CLI) due to obstructive atherosclerosis causes pain and tissue damage and may result in amputation and death. Revascularization saves the limbs and lives of patients with CLI. This review addresses adjunctive tools for lesion crossing, including mechanical atherectomy, laser atherectomy, crossing devices, and luminal reentry devices. Mechanical atherectomy devices are designed to excise atheroma, often heavily calcified, thereby preparing a channel for further intervention. Mechanisms (and devices) include directional (SilverHawk™, TurboHawk™, RockHawk™), rotational (Jetstream™, Pheonix™), and orbital (Diamondback 360°™, Predator 360°™, Stealth 360°™) atherectomy. A laser atherectomy device (Turbo Elite™) vaporizes atheroma by heating tissues with ultraviolet light. Crossing devices specifically designed for chronic total occlusions either navigate a vessel's true lumen or guide a controlled subintimal course with reentry into the distal true lumen. Crossing devices include Crosser® Catheter, Wildcat™, Ocelot™, Kittycat™, TruePath™, Viance™, Frontrunner™, TOTAL across™, and PowerWire™. When a guidewire or crossing device traverses a lesion via a subintimal course, a luminal reentry device may facilitate deployment of the guidewire in the distal vessel lumen. Reentry devices include Outback LTD™, Offroad™, Pioneer Plus™, and Enteer™.

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Xu, Pei Long, Na Na, and Lei Shang. "Effects of Potential Enviromental Pollutant Acaricide Fenpyroximate on Juvenile Turbot (Scophthalmus Maximus)." Advanced Materials Research 634-638 (January 2013): 1319–22. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1319.

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Juvenile turbot (Scophthalmus maximus) were exposed to acaricide fenpyroximate, and the subsequent histological, enzyme activity changes of liver tissue were examined. Histopathological examinations showed that the turbot liver is the target organ for the acaricide fenpyroximate. Analysis of liver antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), in the exposed turbots also showed similar changes. These changes indicated that fenpyroximate caused the oxidative stress on the turbot liver, which induced the damage of antioxidant enzymes system and possible interruption of the mitochondrial redox respiratory chain. This could be one toxic mechanism of fenpyroximate to the juvenile turbot.

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Sinnecker, Tim, Ivan Bozin, Jan Dörr, Caspar F. Pfueller, Lutz Harms, Thoralf Niendorf, Alexander U. Brandt, Friedemann Paul, and Jens Wuerfel. "Periventricular venous density in multiple sclerosis is inversely associated with T2 lesion count: a 7 Tesla MRI study." Multiple Sclerosis Journal 19, no. 3 (June 26, 2012): 316–25. http://dx.doi.org/10.1177/1352458512451941.

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Background: Damage to venules in multiple sclerosis was first described decades ago. Today, ultrahigh magnetic field strength T2*-weighted magnetic resonance imaging (MRI) techniques depict very small cerebral veins in vivo with great anatomical detail. Objective: We aimed to investigate alterations of periventricular small blood vessel appearance in relation to T2 lesion count and distribution in multiple sclerosis and clinically isolated syndrome in comparison with healthy control subjects at 7 Tesla MRI. Methods: We investigated 38 patients (including 16 with early multiple sclerosis and seven with clinically isolated syndrome) and 22 matched healthy controls at 7 Tesla. The protocol included T2*-weighted Fast Low Angle Shot, and T2-weighted Turbo Inversion Recovery Magnitude sequences. We quantified periventricular venous density by a novel region-of-interest-based algorithm, expressing the ratio of ‘veins per region-of-interest’ as well as of ‘periventricular vascular area’. Results: Our study revealed significantly decreased venous density in multiple sclerosis patients compared with healthy controls. Venous alterations were already detectable in clinically isolated syndrome and early multiple sclerosis, although to a smaller extent. Venous density correlated inversely with periventricular and whole-brain T2 lesion count. Furthermore, we found no indication for cerebral venous congestion in multiple sclerosis. Conclusion: High spatially resolving anatomical T2*-weighted MRI revealed vascular alterations in early stages of multiple sclerosis, presumably as a part of widespread haemodynamic and metabolic alterations.

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Sharma, Aarti, Shivshankar Lasune, Rupakala B. M., Harshitha Reddy, and Vineeta Yadav. "A case report of tubo-ovarian torsion in 4 years old girl." International Journal of Reproduction, Contraception, Obstetrics and Gynecology 6, no. 9 (August 28, 2017): 4144. http://dx.doi.org/10.18203/2320-1770.ijrcog20174079.

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Tubo-ovarian torsion is infrequent diagnosis, clinical picture is nonspecific and children cannot articulate their symptoms which make diagnosis as a challenge. High index of suspicious and early intervention prevents damage to adnexal tissue.

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Yu, Tao, Ying Yang, Qing Kai Han, Hong Liang Yao, and Bang Chun Wen. "ANN-Based Crack Identification in Rotor System with Multi-Crack in Shaft." Key Engineering Materials 353-358 (September 2007): 2463–66. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.2463.

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Rotating machinery, such as steam turbo, compressor, and aeroengine etc., are widely used in many industrial fields. Among the important rotor faults, the fatigue crack fault, which can lead to catastrophic failure and cause injuries and severe damage to machinery if undetected in its early stages, is most difficult to detect efficiently with traditional methods. In the paper, based on the truth of the change of the mode shapes of the cracked structure, a new method by combining accurate finite element model of rotor with multi-crack in shaft and artificial neural network (ANN) is proposed to identify the location and depth of cracks in rotating machinery. First, based on fracture mechanics and the energy principle of Paris, the accurate FE model of the rotor system considering several localized on-edge non-propagating open cracks with different depth, is built to produce the specific mode shapes. Then a set of different mode shapes of a rotor system with localized cracks in several different positions and depths, which will be treated as the input of the designed ANN model, can be obtained by repeating the above step. At last, with several selected crack cases, the errors between the results obtained by using the trained ANN model and FEM ones are compared and illustrated. Meanwhile, the influences of crack in the different position on the identification success are analyzed. The method is validated on the test-rig and proved to have good effectiveness in identification process.

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MERKISZ, Jerzy, and Marek WALIGÓRSKI. "Recognition of combustion process irregularities in small volume displacement diesel engines with the use of non-dimensional characteristics of the vibration signal." Combustion Engines 169, no. 2 (May 1, 2017): 18–23. http://dx.doi.org/10.19206/ce-2017-204.

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The subject of the considerations described in the paper is the problem of early detection of abnormalities and damages during operation process of the turbo diesel engine with small volume displacement and direct fuel injection, which is used in modern LDV vehicles dedicated especially for urban areas, in the context of present and future requirements for a technical object diagnostics, taking into account the criteria of optimizing overall efficiency, toxic compound emission and safety of the object in real conditions of its operation. The paper presents the results of empirical research of vibroacoustic signal application to the diagnostic evaluation of correctness of short-time engine main processes. The evaluation of the combustion process variability from structural and operational abnormalities by using dimensionless estimates of a vibration process was conducted, and functional characteristics necessary to built the diagnostic algorithm in accordance with the requirements of on-board diagnostics were obtained.

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Arakere, Nagaraj K., and Gregory Swanson. "Fretting Stresses in Single Crystal Superalloy Turbine Blade Attachments." Journal of Tribology 123, no. 2 (June 27, 2000): 413–23. http://dx.doi.org/10.1115/1.1308032.

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Single crystal nickel base superalloy turbine blades are being utilized in rocket engine turbopumps and turbine engines because of their superior creep, stress rupture, melt resistance, and thermomechanical fatigue capabilities over polycrystalline alloys. High cycle fatigue induced failures in aircraft gas turbine and rocket engine turbopump blades is a pervasive problem. Blade attachment regions are prone to fretting fatigue failures. Single crystal nickel base superalloy turbine blades are especially prone to fretting damage because the subsurface shear stresses induced by fretting action at the attachment regions can result in crystallographic initiation and crack growth along octahedral planes. This paper presents contact stress evaluation in the attachment region for single crystal turbine blades used in the NASA alternate advanced high pressure fuel turbo pump for the space shuttle main engine. Single crystal materials have highly anisotropic properties making the position of the crystal lattice relative to the part geometry a significant factor in the overall analysis. Blades and the attachment region are modeled using a large-scale three-dimensional finite element model capable of accounting for contact friction, material anisotropy, and variation in primary and secondary crystal orientation. Contact stress analysis in the blade attachment regions is presented as a function of coefficient of friction and primary and secondary crystal orientation. Fretting stresses at the attachment region are seen to vary significantly as a function of crystal orientation. The stress variation as a function of crystal orientation is a direct consequence of the elastic anisotropy of the material. Fatigue life calculations and fatigue failures are discussed for the airfoil and the blade attachment regions.

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Witek, Lucjan. "Experimental and Numerical Crack Initiation Analysis of the Compressor Blades Working in Resonance Conditions." Fatigue of Aircraft Structures 2011, no. 3 (August 1, 2011): 134–53. http://dx.doi.org/10.2478/v10164-010-0045-3.

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Experimental and Numerical Crack Initiation Analysis of the Compressor Blades Working in Resonance ConditionsThis paper presents the results of a complex experimental and numerical crack initiation analysis of the helicopter turbo-engine compressor blades subjected to vibrations. A nonlinear finite element method was utilized to determine the stress state of the blade during the first mode of transverse vibration. In this analysis, the numerical models without defects as well as those with V-notches were defined. The quality of the numerical solution was checked by the convergence analysis. The obtained results were next used as an input data into crack initiation (ε-N) analyses performed for the load time history equivalent to one cycle of the transverse vibration. In the fatigue analysis, the different methods such as: Neuber elastic-plastic strain correction, linear damage summation and Palmgreen-Miner rule were utilized. As a result of ε-N analysis, the number of load cycles to the first fatigue crack appearing in the compressor blades was obtained. Moreover, the influence of the blade vibration amplitude on the number of cycles to the crack initiation was analyzed. Values of the fatigue properties of the blade material were calculated using the Baumel-Seeger and Muralidharan methods. The influence of both the notch radius and values of the UTS of the blade material on the fatigue behavior of the structure was also considered. In the last part of the work, the finite element results were compared with the results of experimental vibration HCF tests performed for the compressor blades.

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Witek, Lucjan. "Stress Intensity Factor Calculations for the Compressor Blade with Half-Elliptical Surface Crack Using Raju-Newman Solution." Fatigue of Aircraft Structures 2011, no. 3 (August 1, 2011): 154–65. http://dx.doi.org/10.2478/v10164-010-0046-2.

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Stress Intensity Factor Calculations for the Compressor Blade with Half-Elliptical Surface Crack Using Raju-Newman Solution This paper presents results of the stress intensity factor calculations for the compressor blade including a half-elliptical crack, subjected to vibration. In this analysis, the Raju-Newman empirical solution for stress intensity factor calculations in the rectangular plate with a half-elliptical flaw was used. The bending stress used in the Raju-Newman solution was computed for the real blade using the finite element method. The K-factor values were calculated only at one point of the crack front, where the crack tip contacts the free surface, because the crack length during experimental investigations was measured just in this direction. In order to determine the stress intensity factors for different crack sizes, ten diverse flaws in the blade were defined. Results of the experimental fatigue tests performed for the blade without preliminary defects showed that the cracks developed from the convex blade surface. On the blade fracture, the beach marks typical of the fatigue damage were visible. The dimensions of cracks in the rectangular plate were defined based on the beach marks shape. In the next part of the work, the stress intensity factor values were used as an input data into the Paris-Erdogan equation. As a result of this calculation, the crack growth rate for the compressor blade vibrating at constant amplitude was estimated. The results obtained were finally compared with the results of the experimental crack growth analysis performed for 1st stage compressor blades of the helicopter turbo-engine.

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Krohn, Michaela, Leonie S. Braum, Joachim Sieper, In-Ho Song, Anja Weiß, Johanna Callhoff, Christian E. Althoff, Bernd Hamm, and Kay-Geert A. Hermann. "Erosions and Fatty Lesions of Sacroiliac Joints in Patients with Axial Spondyloarthritis: Evaluation of Different MRI Techniques and Two Scoring Methods." Journal of Rheumatology 41, no. 3 (February 1, 2014): 473–80. http://dx.doi.org/10.3899/jrheum.130581.

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Objective.Assessment of structural damage of sacroiliac joints (SIJ) in patients with axial spondyloarthritides (axSpA) has been discussed as a useful outcome measure in clinical trials. The aim of our study was to evaluate different magnetic resonance imaging (MRI) scoring methods and pulse sequences with a focus on fatty lesions and bony erosions.Methods.Seventy-five patients with the diagnosis of axSpA underwent MRI at 3 timepoints as part of the ESTHER trial, which compared 2 groups of patients treated with etanercept or sulfasalazine. Two MRI sequences [unenhanced T1-weighted (T1w) turbo spin-echo (TSE) and unenhanced T1w opposed-phase gradient-echo sequences (opGRE)] and 2 different scoring systems (simple and comprehensive Berlin method) were used for the evaluation of fatty lesions and erosions of the SIJ. Differences between techniques and methods were evaluated by intraclass correlation coefficients (ICC) and standardized response means (SRM).Results.Applying the simple Berlin method, mean fatty lesion scores for etanercept-treated patients were 4.59 and 5.19 at baseline and Week 48, respectively, while the comprehensive Berlin method revealed mean fatty lesion scores of 6.59 and 7.64, respectively. Corresponding SRM were 0.59 and 0.86 for simple and comprehensive methods, respectively, while ICC dropped from 0.76–0.77 to 0.59–0.62. Scoring of erosions on T1w opGRE images resulted in a higher interreader agreement (ICC of 0.65) compared to T1w TSE sequences (ICC of 0.18).Conclusion.Better characterization of fatty lesion changes within 1 year was achieved by the comprehensive Berlin scoring method; however, more reader variation has to be taken into account. The delineation of erosions is markedly improved when using T1w opGRE pulse sequences.

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De Paepe, Katja N., David M. Higgins, Iain Ball, Veronica A. Morgan, Desmond P. Barton, and Nandita M. deSouza. "Visualizing the autonomic and somatic innervation of the female pelvis with 3D MR neurography: a feasibility study." Acta Radiologica 61, no. 12 (March 25, 2020): 1668–76. http://dx.doi.org/10.1177/0284185120909337.

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Background Treatment of female pelvic malignancies often causes pelvic nerve damage. Magnetic resonance (MR) neurography mapping the female pelvic innervation could aid in treatment planning. Purpose To depict female autonomic and somatic pelvic innervation using a modified 3D NerveVIEW sequence. Material and Methods Prospective study in 20 female volunteers (n = 6 normal, n = 14 cervical pathology) who underwent a modified 3D short TI inversion recovery (STIR) turbo spin-echo (TSE) scan with a motion-sensitive driven equilibrium (MSDE) preparation radiofrequency pulse and flow compensation. Modifications included offset independent trapezoid (OIT) pulses for inversion and MSDE refocusing. Maximum intensity projections (MIP) were evaluated by two observers (Observer 1, Observer 2); image quality was scored as 2 = high, 1 = medium, or 0 = low with the sciatic nerve serving as a reference. Conspicuity of autonomic superior (SHP) and bilateral inferior hypogastric plexuses (IHP), hypogastric nerves, and somatic pelvic nerves (sciatic, pudendal) was scored as 2 = well-defined, 1 = poorly defined, or 0 = not seen, and inter-observer agreement was determined. Results Images were of medium to high quality according to both observers agreeing in 15/20 (75%) of individuals. SHP and bilateral hypogastric nerves were seen in 30/60 (50%) of cases by both observers. Bilateral IHP was seen in 85% (34/40) by Observer 1 and in 75% (30/40) by Observer 2. Sciatic nerves were well identified in all cases, while pudendal nerves were seen bilaterally by Observer 1 in 65% (26/40) and by Observer 2 in 72.5% (29/40). Agreement between observers for scoring nerve conspicuity was in the range of 60%–100%. Conclusion Modified 3D NerveVIEW renders high-quality images of the female autonomic and pudendal nerves.

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Pachowsky, M., S. Söllner, A. Kleyer, G. Welsch, and G. Schett. "OP0109 CARTILAGE LESIONS OF THE KNEE: GAGCEST IMAGING AT 3 T MRI AND INTRAOPERATIVE VALIDATION." Annals of the Rheumatic Diseases 80, Suppl 1 (May 19, 2021): 60.1–61. http://dx.doi.org/10.1136/annrheumdis-2021-eular.1822.

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Background:Morphological Magnetic Resonance Imaging (MRI) has become the accepted diagnostic tool for non-invasive evaluation of cartilage lesions1. Emerging techniques including chemical exchange saturation transfer (CEST) can be used to visualize microstructural and biochemical changes to the cartilage matrix even before morphological damage is visible2,3. CEST is a promising technique based on detecting the chemical exchange between bulk water protons and protons bound to solutes. This technique renders the possibility to function as a biomarker for glycosaminoglycan (GAG/gag) content for instance in cartilage of joints.Objectives:The aim of the study was to compare glycosaminoglycan chemical exchange saturation transfer (gagCEST) of knee cartilage with intraoperative results for the assessment of early osteoarthritis (OA) and to define gagCEST values for the differentiation between healthy and degenerated cartilage.Methods:Patients with cartilage lesions or moderate OA were preoperatively examined using 3T Magnetic Resonance Imaging (MRI). In this prospective study, regions of interest (ROIs) were examined by a sagittal gagCEST analysis and a morphological high-resolution three-dimensional, fat-saturated proton-density space sequence. Cartilage lesions were identified arthroscopically, graded by the International Cartilage Repair Society (ICRS) score in 42 defined ROIs per patient and consecutively compared with mean gagCEST values using analysis of variance and Spearman’s rank correlation test. Receiver operating characteristics (ROC) curves were applied to identify gagCEST threshold values to differentiate between the ICRS grades.aResults:Twenty-one patients with cartilage lesions or moderate OA were examined. The imaging assessment consisted of a total of 882 ROIs which were examined and graduated in ICRS score 0 (67.3%), 1 (25.2%), 2 (6.2%) and the merged ICRS 3 and 4 (1.0%). gagCEST values decreased with increasing grade of cartilage damage with a negative correlation between gagCEST values and ICRS scores. A gagCEST value threshold of 3.55% was identified to differentiate between ICRS score 0 (normal) and all other grades.Conclusion:Conclusions. gagCEST reflects the content of glycosaminoglycan and might provide a diagnostic tool for the detection of early knee-joint cartilage damage and for the non-invasive subtle differentiation between ICRS grades by MRI even at early stages in clinical practice.References:[1]Crema, M.D., M.H. Nogueira-Barbosa, F.W. Roemer, M.D. Marra, J. Niu, F.A. Chagas-Neto, et al., Three-dimensional turbo spin-echo magnetic resonance imaging (MRI) and semiquantitative assessment of knee osteoarthritis: comparison with two-dimensional routine MRI. Osteoarthritis Cartilage, 2013. 21(3): p. 428-33.10.1016/j.joca.2012.12.011[2]Eagle, S., H.G. Potter and M.F. Koff, Morphologic and quantitative magnetic resonance imaging of knee articular cartilage for the assessment of post-traumatic osteoarthritis. J Orthop Res, 2017. 35(3): p. 412-423.10.1002/jor.23345[3]Liebl, H., G. Joseph, M.C. Nevitt, N. Singh, U. Heilmeier, K. Subburaj, et al., Early T2 changes predict onset of radiographic knee osteoarthritis: data from the osteoarthritis initiative. Ann Rheum Dis, 2015. 74(7): p. 1353-9.10.1136/annrheumdis-2013-204157Disclosure of Interests:None declared

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Mohran, T. Z., M. M. Omar, M. A. Hameed, and M. S. Elnaggar. "Magnetic resonance imaging evaluation of radiation: Cranial radiation therapy-induced diffuse white matter injury." Journal of Clinical Oncology 27, no. 15_suppl (May 20, 2009): e13033-e13033. http://dx.doi.org/10.1200/jco.2009.27.15_suppl.e13033.

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e13033 Background: To study the value of MRI in detection and grading of diffuse white matter injury induced by cranial radiation therapy for brain tumors and to evaluate the influence of various risk factors for its development. Methods: This study included 60 patients who had primary brain tumors and received external beam conventionally fractionated radiotherapy. Twenty-three out of 60 patients received chemotherapy after radiotherapy. Post radiotherapy follow-up MRI examination was performed for all patients at 6 weeks, 3, 6, 9, 12 months, and at more than 1 year from completion of radiotherapy. MR imaging was performed with T2-weighted turbo spin echo, fast fluid-attenuated inversion- recovery (FLAIR), T1-weighted spin-echo, and T1-weighted post-contrast spin-echo sequences. Results: Twenty-one of 60 patients (35%) developed diffuse white matter injury at a mean of 15.3 + 7.6 months from the completion of radiotherapy (range, 5–36 months). Radiation-related diffuse white matter changes were characterized as diffuse high signal intensity in the periventricular deep white matter on T2WI and FLAIR sequences. The MRI grading system of these periventricular hyperintensity (PVH) were as follow: 39 patients (65%) had no WMI (grade 0), four had grade 1 changes, three patients had grade 2 changes, nine patients had grade 3, and five patients had grade 4. They were symmetrical in 13 of 21 patients (61.9%), and asymmetrical in eight out of 21 patients (38.1%). The prevalence of diffuse matter injury found to be significantly related to the volume of irradiation (p = 0.02), fraction size (p = 0.008), and concomitant use of chemotherapy (p > 0.02)Conclusions: Diffuse white matter injury is a known consequence of radiation therapy, and the capability of detecting and grading such damage is optimally provided by MRI. No significant financial relationships to disclose.

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Goanvec, Christelle, Michaël Theron, Elisabeth Poirier, Stéphane Le Floch, Jean Laroche, Liliane Nonnotte, and Guy Nonnotte. "Evaluation of chromosomal damage by flow cytometry in turbot (Scophthalmus maximusL.) exposed to fuel oil." Biomarkers 9, no. 6 (January 2004): 435–46. http://dx.doi.org/10.1080/13547500400027001.

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Telli-Karakoç, F., P. J. Ruddock, D. J. Bird, A. Hewer, A. Van Schanke, D. H. Phillips, and L. D. Peters. "Correlative changes in metabolism and DNA damage in turbot (Scophthalmus maximus) exposed to benzo[a]pyrene." Marine Environmental Research 54, no. 3-5 (September 2002): 511–15. http://dx.doi.org/10.1016/s0141-1136(02)00192-7.

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Rempel, Mary Ann, Yinsheng Wang, Jeff Armstrong, and Daniel Schlenk. "Uptake of estradiol from sediment by hornyhead turbot (Pleuronichthys verticalis) and effects on oxidative DNA damage in male gonads." Marine Environmental Research 66, no. 1 (July 2008): 111–12. http://dx.doi.org/10.1016/j.marenvres.2008.02.039.

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Berrou, Claude, Charlotte Langlais, and Yi Yu. "Turbo codes and turbo algorithms." Journal of Communications Software and Systems 2, no. 3 (April 5, 2017): 179. http://dx.doi.org/10.24138/jcomss.v2i3.282.

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In the first part of this paper, several basic ideas that prompted the coming of turbo codes are commented on. We then present some personal points of view on the main advances obtained in past years on turbo coding and decoding such as the circular trellis termination of recursive systematic convolutional codes and double-binary turbo codes associated with Max-Log-MAP decoding. A novel evaluation method, called genieinitialised iterative processing (GIIP), is introduced to assess the error performance of iterative processing. We show that using GIIP produces a result that can be viewed as a lower bound of the maximum likelihood iterative decoding and detection performance. Finally, two wireless communication systems are presented to illustrate recent applications of the turbo principle, the first one being multiple-input/multiple-output channel iterative detection and the second one multi-carrier modulation with linear precoding.

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Raphaeli, D., and Y. Zarai. "Combined turbo equalization and turbo decoding." IEEE Communications Letters 2, no. 4 (April 1998): 107–9. http://dx.doi.org/10.1109/4234.664220.

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Chen, Zhichu, Sifan Zhao, Yang Liu, Pei Yang, Qinghui Ai, Wenbing Zhang, Weiqi Xu, Yongan Zhang, Yanjiao Zhang, and Kangsen Mai. "Dietary citric acid supplementation alleviates soybean meal-induced intestinal oxidative damage and micro-ecological imbalance in juvenile turbot, Scophthalmus maximus L." Aquaculture Research 49, no. 12 (October 19, 2018): 3804–16. http://dx.doi.org/10.1111/are.13847.

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Bhandari, Ruchi, Manju Khemani, and Asif Mustafa. "Cases of management of paediatric tubo-ovarian torsion." International Journal of Reproduction, Contraception, Obstetrics and Gynecology 8, no. 7 (June 29, 2019): 2888. http://dx.doi.org/10.18203/2320-1770.ijrcog20193062.

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Ovarian torsion is the fifth most common cause of gynaecologic surgical emergency. It warrants early diagnosis as timely surgical management will avoid the further adnexal injury. In paediatric population, this is especially dangerous as the condition can go undiagnosed because of its rarity and nonspecific presentation. This leads to delay in surgical exploration and loss of ovarian function. In these cases, the ovary and often the ipsilateral fallopian tube twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion leads to haemorrhagic infarction. We encountered 3 cases of ovarian torsion in paediatric age group during a period of 12 months. All cases presented with acute pain abdomen for 3-7 days period with loss of appetite and unable to pass motion with varied disappearance of pain. On ultrasound all the cases were diagnosed with ovarian cyst with torsion and underwent laparoscopic cystectomy. This case series is written just to show the results of de-torsion and conserving the fallopian tube and ovary after vascular damage. This type of conservative management may give chance to ovary to return to viability. This was seen in all 3 cases dealt by us on repeat scan on follow up. Even on de-torsion if ovary does not regain its colour immediately it should be conserved, and cystectomy should be performed rather than oophorectomy. Conservative surgery, in the form of ovarian de-torsion can be tried in cases of ischemia but if ovarian necrosis has occurred, then salpingo-oophorectomy is performed as the last resort.

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Suryanti, Sri, Yuktiana Kharisma, and Aaron Tigor. "INFILTRATING UROTHELIAL CARCINOMA ALONG THE URINARY TRACT OF A YOUNG ADULT." Indonesian Journal of Urology 28, no. 2 (July 15, 2021): 211–14. http://dx.doi.org/10.32421/juri.v28i2.707.

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Objective: To present a rare case of infiltrating urothelial carcinoma along the urinary tract on a young adult. Case(s) Presentation: A 39 year old Asian male patient with > 20 pack-year smoking history, came to the hospital with a chief complaint of hematuria and flank pain since two weeks ago. Physical examination revealed Eastern Cooperative Oncology Group (ECOG) Performance Status 1, the right kidney was palpated, no tenderness on fist percussion. Abdominal ultrasound (USG) revealed 1.5 cm and 0.5 cm masses located in the urinary bladder. The CT scan show mass in the bladder was exophytic, > 3 cm in size, and occupying lesion was located on the right posteroinferior and left lateral bladder wall accompanied with dilatation of pelvic calyces and right ureter. Histopathology of the specimen revealed low-grade infiltrating urothelial carcinoma of bladder and right ureter. The pathological stage was pT2NxMx, The patient refused neoadjuvant chemotherapy and surgery. Four months after TURBT, he came with weakness and right flank pain. The patient consent to surgery and underwent the right nephroureterectomy. Histopathology of the specimen showed infiltrating urothelial carcinoma of right kidney, ureter, Gerota fascia with lymphovascular invasion (pT3NxMx). Discussion: Urothelial carcinoma (UC) is commonly arising in the urinary bladder, but it can develop along the urinary tract. Cigarette smoke contains a lot of carcinogenic agents and stimulates DNA damage. Conclusion: Upper tract urothelial carcinoma (UTUCs) is subset of UC with a poor prognosis. Cigarette smoking is the main risk factor that induces DNA damage.

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McDonagh, Sorcha. "Turbo Gene." Science News 164, no. 5 (August 2, 2003): 70. http://dx.doi.org/10.2307/3982188.

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Dixon, Philip. "Turbo Rand." American Statistician 42, no. 2 (May 1988): 158. http://dx.doi.org/10.2307/2684493.

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Jezequel, Loig, and Eric Fabre. "Turbo Planning." IFAC Proceedings Volumes 45, no. 29 (2012): 301–6. http://dx.doi.org/10.3182/20121003-3-mx-4033.00049.

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Fortuijn, Lambertus G. H. "Turbo Roundabouts." Transportation Research Record: Journal of the Transportation Research Board 2096, no. 1 (January 2009): 16–24. http://dx.doi.org/10.3141/2096-03.

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Journal articles on the topic 'Damage to the turbo'

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