2 research outputs found
Effects of speeds and weights of travelling vehicles on the road surface temperature
It is important to predict the fatigue conditions of in-service roads for monitoring the state of internal pavement layers, planning the routine maintenance services and for ensuring the safety of travelling vehicles. Among various factors, the frictional heat generated by the tires of moving vehicles is considered to be an important factor causing such a distress in in-service roads. Because of this frictional heat, the temperature of wheel tracks is slightly warmer than other parts of the pavement, thereby, causing a non-uniform distribution of road surface temperature (RST) that may be responsible for developing cracks and subsequent increase in permeability of existing roads. In this study, the effect of travelling vehicles on the RST was investigated by using an infrared (IR) camera in an in-service road. In order to know the actual distribution of temperature, the RSTs were compared between the wheel track of each lane and in-between lanes. Then, the effect of speeds and weights of travelling vehicles on the RST was investigated. A bridge weigh-in-motion (BWIM) system using MEMS accelerometers was utilized to identify the speed and weight of a travelling vehicle. A strong correlation was observed between the rise of RST of wheel tracks due to the friction with the speeds and weights of travelling vehicles. The rate of increase in surface temperature was observed to be higher for the higher axle vehicles. Additionally, an influence of ambient air temperature was observed on the relationship between the rise of RST with the speeds and weights of travelling vehicles
FGF23ârelated hypophosphatemic rickets preceding the onset of systemic lupus erythematosus: A juvenile case
Key Clinical Message This case report describes the clinical course of a juvenile female with FGF23ârelated hypophosphatemic rickets preceding the onset of SLE. Our study demonstrates the possibility of hypophosphatemic rickets as an early symptom of SLE. Abstract Fibroblast growth factor 23 (FGF23)ârelated hypophosphatemic rickets is observed in both genetic and acquired disorders. Various reports describe FGF23ârelated hypophosphatemia with systemic lupus erythematosus (SLE), although FGF23ârelated hypophosphatemia preceding the onset of SLE has never been described. Here, we report the case of a 9âyearâold female with FGF23ârelated hypophosphatemic rickets preceding the onset of SLE. The patient presented to us with arthralgia in the lower extremities and abnormality of gait lasting for 8âmonths. She was diagnosed with FGF23 hypophosphatemic rickets due to the presence of hypophosphatemic rickets symptoms and high serum levels of FGF23. Additional examination excluded hereditary diseases and tumorâinduced osteomalacia. Three months after diagnosis of FGF23ârelated hypophosphatemic rickets, she developed nephritis and was diagnosed with SLE. She was treated with prednisolone, hemodialysis, and diseaseâmodifying drugs, as well as oral sodium phosphate to improve hypophosphatemia. Serum antiâdoubleâstranded DNA antibody (dsDNAab) and plasma tumor necrosis factorâα (TNFâα) were elevated at FGF23ârelated hypophosphatemic rickets diagnosis. During the clinical course, serum FGF23 correlated with dsDNAab and TNFâα serum levels, which are involved in SLE disease activity. In this case, FGF23ârelated hypophosphatemic rickets without hereditary diseases or tumorâinduced osteomalacia occurred before the appearance of juvenile SLE symptoms, and serum FGF23 represented disease activity in SLE