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1.
Sci Rep ; 13(1): 2106, 2023 Feb 06.
Article in English | MEDLINE | ID: mdl-36747010

ABSTRACT

The increase in demand for railway transportation results in a significant need for higher train axle load and faster speed. Weak and sensitive trackforms such as railway switches and crossings (or called 'turnout') can suffer from such an increase in either axle loads or speeds. Moreover, railway turnout supports can deteriorate from other incidences due to extreme weather such as floods which undermine cohesion between ballast leading to ballast washaway or loss of support under turnout structures. In this study, new intelligent automation based on machine learning pattern recognition has been built to detect and predict the deterioration of railway turnouts exposed to flooding conditions which is the scope of this study. Since the turnout system is very complex by nature, different features and smart filtering are explored to find the potential features for deep learning. Nonlinear finite element models validated by actual field measurements are used to mimic the dynamic behaviors of turnout supports under flooding conditions. The study exhibits that the novel recognition model can achieve more than 98% accuracy, yielding the potential capability to recognize and classify turnout support deteriorations facing extreme weather conditions which will be beneficial for responsible parties to schedule and plan maintenance activities.

2.
Sci Rep ; 12(1): 14377, 2022 08 23.
Article in English | MEDLINE | ID: mdl-35999353

ABSTRACT

Railway turnouts are essential in the train traffic route management for modern railways. Despite significant devotion to railway turnout research, one of their most common failures has not been thoroughly investigated, which is a fatigue over the turnout crossing nose. At the crossings, wheel-rail discontinuity imparts high-frequency high-magnitude forces, which are the source of fatigue failure over the crossing nose. In this study, a novel approach built on "Peridynamics" (PD) has been developed to obtain new insights into the fatigue cracks. A recent approach using "crack on mid-plane" has also been employed in this study to enhance the limited capability of Peridynamics. This paper is the world's first to investigate fatigue failures over a crossing nose from fracture mechanics perspective. This paper also introduces a novel adaptive time-mapping method as an alternative to earlier time-mapping methods for fatigue models proposed in the open literature. The new model has been verified against both Finite Element Method and experimental data. It reveals that our new approach can simulate fatigue damage, particularly in mode I crack propagation. The study has provided important insights on the fatigue crack development, which is not possible before by existing Peridynamics fatigue model. The new approach on the basis of "adaptive time-mapping" and "crack on mid-plane" is demonstrated to be effective and efficient in PD simulations.


Subject(s)
Equipment Failure Analysis , Humans
3.
Clin Imaging ; 37(1): 189-91, 2013.
Article in English | MEDLINE | ID: mdl-23206633

ABSTRACT

Polyorchidism, the presence of more than two testes, is a very rare anomaly. We report the color Doppler ultrasonography and magnetic resonance imaging findings of the case of a 20-year-old man with polyorchidism, presenting with an asymptomatic scrotal mass. Ultrasonography showed double testes with double separate epididymides sharing a common vas deferens in the left side of the scrotum. The double testes demonstrated similar echo texture and vascular flow as the normal testis, but smaller in size. Magnetic resonance imaging showed three testes very clearly and confirmed the diagnoses. After 2 years of follow-up, he was managed with surgical intervention. Pathology report revealed polyorchidism.


Subject(s)
Gonadal Dysgenesis/diagnosis , Magnetic Resonance Imaging/methods , Testis/abnormalities , Ultrasonography, Doppler, Color/methods , Humans , Male , Testis/diagnostic imaging , Testis/pathology , Young Adult
4.
Chin J Physiol ; 53(3): 145-50, 2010 Jun 30.
Article in English | MEDLINE | ID: mdl-21793322

ABSTRACT

The aim of the study was to evaluate protective effects of exogenous leptin on ischemia/reperfusion (I/R)-induced injuries to the urinary bladder tissue and to investigate the effect on tumor necrosis factor alpha (TNF-alpha) levels and apoptotic cells during I/R injury. Bladder I/R injury was induced by abdominal aorta occlusion by ischemia for 45 min, followed by 60 min of reperfusion in rats. The rats were divided into three groups: control (n = 8 + 8), I/R (n = 8 + 8) and I/R+leptin group (n = 8 + 8). The rats in the I/R+leptin group were treated intraperitoneally with leptin (10 microg/kg) 60 min prior to ischemia induction. At the end of the reperfusion period, urinary bladders of the first eight rats from each group were removed for TUNEL staining processing while the others were removed for biochemical analyses for MDA and TNF-alpha levels. In the I/R group, the ratios of TUNEL-positive nuclei were higher than the control and the I/R+leptin groups. The MDA and TNF-alpha levels of the bladder tissue in the I/R group were higher than the control and leptin-treated groups. TUNEL-staining and biochemical studies revealed that leptin has a protective effect on urinary bladder I/R injury.


Subject(s)
Ischemia/physiopathology , Leptin/therapeutic use , Reperfusion Injury/prevention & control , Urinary Bladder/blood supply , Animals , Apoptosis/drug effects , Apoptosis/physiology , Injections, Intraperitoneal , Ischemia/metabolism , Ischemia/pathology , Leptin/administration & dosage , Leptin/pharmacology , Malondialdehyde/metabolism , Models, Animal , Rats , Rats, Sprague-Dawley , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Tumor Necrosis Factor-alpha/metabolism
5.
Acta Diabetol ; 46(3): 197-202, 2009 Sep.
Article in English | MEDLINE | ID: mdl-18989612

ABSTRACT

The aim of this prospective study was to evaluate the morbidity of invasive urodynamic study (UDS) in type 2 diabetic patients. Study was conducted on 94 diabetic (59.4 +/- 0.8 years) and 110 non-diabetic (58.1 +/- 0.9 years) patients who had lower urinary tract symptoms. All patients underwent pressure-flow study. The major complication rate after UDS, including urinary tract infection, fever, urinary retention and gross hematuria, was 11.8% for non-diabetics and 22.3% for diabetics (p = 0.044). No significant differences were found between diabetics and non-diabetics according to gender with respect to dysuria, hematuria and pain (p > 0.05). Existence of pyuria before UDS was significantly higher in diabetic women with major complication than without major complication (p = 0.011). On the other hand, residual urine volume (p = 0.004) and diabetic cystopathy (0.005) were found significantly higher in diabetic men with major complication than without major complication. Our study demonstrated that UDS has an important role on the occurrence of high objective and subjective morbidity in diabetic and non-diabetic patients. Therefore, UDS indication should be carefully evaluated, especially in diabetic men who have high residual urine volume and diabetic women who have pyuria before UDS.


Subject(s)
Diabetes Mellitus, Type 2/epidemiology , Diagnostic Techniques, Urological/adverse effects , Urodynamics/physiology , Diabetes Mellitus, Type 2/complications , Female , Humans , Male , Middle Aged , Morbidity , Risk Factors , Urinalysis , Urinary Tract Infections/etiology
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