I. ABSTRACTMillimeter-wave (mmW) radars are being increasingly integrated in commercial vehicles to support new Adaptive Driver Assisted Systems (ADAS) for its ability to provide high accuracy location, velocity, and angle estimates of objects, largely independent of environmental conditions. Such radar sensors not only perform basic functions such as detection and ranging/angular localization, but also provide critical inputs for environmental perception via object recognition and classification. To explore radar-based ADAS applications, we have assembled a lab-scale frequency modulated continuous wave (FMCW) radar test-bed (https://depts.washington.edu/funlab/research) based on Texas Instrument's (TI) automotive chipset family. In this work, we describe the test-bed components and provide a summary of FMCW radar operational principles. To date, we have created a large raw radar dataset for various objects under controlled scenarios. Thereafter, we apply some radar imaging algorithms to the collected dataset, and present some preliminary results that validate its capabilities in terms of object recognition. (a) (b) Fig. 1: (a) FMCW radar test-bed (red board: AWR1642 BOOST; green board: DCA1000 EVM) (b) Vehicle mounted platform for dataset collection II. INTRODUCTIONOver the years, advances in 77GHz RF design with integrated digital CMOS and packaging have enabled low-cost radaron-chip and antenna-on-chip systems [1]. As a result, several vehicular radar vendors are refining their radar chipset solutions for the automotive segment. TI's state-of-art 77GHz FMCW radar chips and corresponding evaluation boards -AWR1443, AWR1642, and AWR1843 -are built with the low-power 45nm RF CMOS process and enable unprecedented levels of integration in an extremely small form factor [2]. Uhnder has also recently unveiled a new, all-digital phase modulated continuous wave (PMCW) radar chip that uses the 28nm RF CMOS process and is capable of synthesizing multiple input multiple output (MIMO) radar capability with 192 virtual receivers, thereby obtaining a finer angular resolution [3]. However, compared to FMCW radars, PMCW radars shift the modulation complexity/precision to the high-speed dataconverters and the DSP. Overall, continual progress in radar chip designs is expected to enable further novel on-platform integration and, consequently lead to enhanced performance in support of ADAS elements such as adaptive cruise control, auto emergency braking, and lane change assistance [1].The above applications fundamentally rely on advanced radar imaging, detection, clustering, tracking, and classification algorithms. Significant research in the context of automotive radar classification has demonstrated its feasibility as a good alternative when optical sensors fail to provide adequate performance.[4] reported that with handcrafted feature extraction from range and Doppler profile, over 90% accuracy can be achieved when using the support vector machine (SVM) algorithm to distinguish cars and pedestrians. Other studies used the short...

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Intensified plaque acidogenicity in caries–prone subjects was reported many years ago, but emerging evidence has suggested that the relationship may not be as strong as once thought. We have now determined a range of acidogenicity variables in subjects having both caries prevalence and incidence data, and have included plaque mineral data in the analysis. pH measurements were made in 20 randomly selected subjects from a high–caries group (mean DMFS = 8.95) and 20 from a caries–free group of Beijing children aged 12 years participating in a caries prediction study. Subgroups with a 12–month DMFS increment ≥2 or = 0 were also formed from the two groups, respectively. Measurements were made with an iridium oxide electrode inserted between teeth 13/14, 23/24, 34/35 and 44/45, before and every 5 min for 30 min after rinsing with 10% sucrose, and the 4 resulting ‘Stephan curves’ averaged using a plaque pH analysis program. Supragingival plaque was collected from buccal and lingual smooth surfaces of posterior and upper anterior teeth and its acid extract analysed for Ca, P and F. Caries–free subjects (based on past experience) had a significantly higher maximum plaque pH and pH value after 30 min (reflecting a faster return to resting pH), a lower minimum enamel dissolution capacity of plaque and recorded less time below pH 7.0 than did high–caries subjects. No other differences were significant, including those of the principal acidogenic parameters ‘minimum pH attained after a sugar rinse’, ‘curve area below the critical pH of 5.5’ and ‘time below the critical pH’. Selection of the caries groups on the basis of both experience and incidence did not reveal significant differences in more parameters. Upper arch plaque was significantly more acidogenic than lower arch plaque, and there was a consistently strong association between upper and lower arch values in individuals. Ca, P and F in the subjects’ plaque had little or no influence on the principal acidogenic parameters. Our failure to find a relationship between caries prevalence or activity and these principal acidogenicity parameters may be related to differences between fissure and smooth surface plaque, temporal variations in acidogenicity and/or to use of F toothpaste during the 1–year observation period. These results support the view that factors such as the frequency of acidogenic episodes may be more important in caries progression than the degree of acidogenicity during any one episode.

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The aim of the present study was to analyze the changes of plasma and urinary prostaglandin E2 (PGE2) levels in preterm infants with symptomatic patent ductus arteriosus (sPDA) treated with oral ibuprofen and acetaminophen. A total of 87 preterm infants with sPDA admitted to the Neonatal Ward of the Affiliated Xuzhou Hospital of Medical College of Southeast University from October, 2012 to June, 2015 were selected and randomly divided into the ibuprofen group (n=43, 10 mg/kg ibuprofen administered orally as initial dose, followed by 5 mg/kg during the first 24 and 48 h later) and acetaminophen group (n=44, 15 mg/kg acetaminophen administered orally once every 6 h for three days). The levels of plasma and urinary PGE2 in the two groups were estimated before and after treatment. The treatment of sPDA infants with ibuprofen (ibuprofen group) or acetaminophen (acetaminophen group) caused a significant decrease in the plasma and urinary PGE2 levels in comparison with plasma and urinary PGE2 levels before treatment (P<0.05). Furthermore, plasma and urinary PGE2 levels in the acetaminophen group (45.0±36.9 ng/l) were significantly lower than those in the ibuprofen group (73.5±44.8 ng/l, P=0.002). The arterial duct closure rate was similar between the acetaminophen [31 (70.5%)] and ibuprofen groups [33 (76.7%), P=0.506]. The incidence of oliguria was less among sPDA infants of the acetaminophen group [1 (2.3%)] than observed among the sPDA infants of the ibuprofen group [6 (14.0%)]; however, this difference was not statistically significant (P=0.108). Additionally, the incidences of fecal occult blood positive rate, intraventricular hemorrhage, neonatal necrotizing enterocolitis and bronchopulmonary dysplasia were distributed similarly in the ibuprofen and acetaminophen groups (P>0.05). The levels of platelet, serum creatinine and alanine transaminase showed no significant changes between the ibuprofen and acetaminophen groups (P>0.05). Following treatment with ibuprofen or acetaminophen, the extent of decrease of plasma and urinary PGE2 was significantly higher among sPDA infants with oliguria (135.0±38.0 ng/l) than that observed in sPDA infants without oliguria (52.5±37.0 ng/l) (P=0.01). The study also found a significant correlation between plasma and urinary PGE2 levels (r=0.648, P=0.01) and the coefficient of variation of urinary PGE2 (0.427) was less than that of plasma PGE2 (0.539). The clinical efficacy of oral ibuprofen and acetaminophen in the treatment of preterm infants with sPDA was similar with low adverse events, whereas acetaminophen-induced PGE2 levels were less than the levels observed in the ibuprofen-treated group. The incidence of oliguria was also lower in the acetaminophen group compared to the ibuprofen group. In addition, monitoring urinary PGE2 levels was more suitable because of its non-invasiveness in the clinical setting than monitoring of plasma PGE2 in preterm infants with sPDA.