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CT-based computations of fractional flow reserve (FFR) have been widely utilized for evaluating functional severity of a coronary artery stenosis. Whilst this approach has been successful clinically, assumptions involved in the analysis still need to be investigated for further improvement in predictive accuracy. To better understand the sensitivity of computational FFRs on outflow boundary condition – typically reflecting patient's own physiology only through anatomical features – FFR computations for 10 patients with different degree of stenosis was conducted. The computations were based on 3D anatomical model reconstructed from CT images and patient-specific in/outflow boundary conditions (BC). Two outflow BCs were considered: (1) conventional morphology-based and (2) PET perfusion-based conditions. The results showed that the FFRs derived from the two boundary conditions agree in general. It was also found that the FFRs computed with the morphology-based BC tend to estimate higher functional severity, especially in patients with reduced vasodilatory response under hyperaemia – an essential physiological condition in FFR measurement. Further investigation was made by varying hyperaemic resistances (30%-90% of the baseline) in the morphology-based BC. The variation of FFR for the varied resistances was narrow for patients with mild stenosis and wider for those who have severe stenosis. This latter approach confirmed that variability of FFR due to outflow condition tends to come from overestimation of vasodilatory response, especially those who have abnormal myocardial perfusion. The results suggest that outflow conditions that are more representative of each patient could be an effective way to improve CT-based FFR computation.

Introduction: Obesity and type 2 diabetes mellitus (T2DM) are growing health concerns. A ten-fold increase of T2DM was noted in the Hong Kong paediatric population from 1997 to 2007. T2DM is often asymptomatic at presentation, but complications can emerge rapidly, especially in youngsters. Experience in Japan, Korea and Taiwan suggests that urine glucose screening is a practical and non-invasive screening tool for identification of T2DM. The Hong Kong Student Health Service (SHS) offers yearly health checks for students and is a good platform for screening of T2DM since attendance rate is over 90% for primary school students and over 70% for secondary school students. Method: In 2005, SHS and the Hong Kong Paediatric Society formulated a protocol on urine glucose screening for early diagnosis of T2DM in students with obesity. Students between the ages of 10–18 years old with age- and sex- specific body mass index (BMI) >97th percentile were recruited. Those screened positive for glycosuria were referred to paediatric departments for workup under a standardized protocol, whilst those who screened positive for both glucose and ketones were referred to the emergency departments. Students enrolled from school year 2005–2006 to 2017–2018 were included. Demographic data, clinical presentation, investigatory results and co-morbidities were captured using a structured reply letter. Results: A total of 219,276 eligible students attended SHS in the years specified and 216,528 students (99%) completed urine glucose screening. 381 (0.18%) students were tested positive for urine glucose; 18 (4.7%) had concomitant urine ketones. In total 120 students had T2DM, 41 had pre-diabetes [impaired fasting glucose and /or impaired glucose tolerance] and 126 turned out normal. 43 students defaulted the referrals and 51 students had known diabetes. 21 students (17.5%) were started on insulin therapy upon diagnosis. A significant proportion of students with T2DM had co-morbidities including raised alanine amino-transferase (57%), hypercholesterolaemia (59%), and hypertension (13%). Five students (4.2%) had microalbuminuria at presentation. Of those with ketonuria, two students had serum glucose of over 20mmol/L and required fluid resuscitation ± insulin infusion in high dependency unit. Conclusion: Our pick up rate for T2DM from students with obesity aged 10–18 years using urine glucose is 0.05% (120/216,528). According to the Hong Kong Childhood Diabetes Registry, the crude incidence of T2DM for this age group was 6.16 /100,000/year over the study period, which equates to 506 new cases of T2DM. Thus 24% of the new T2DM cases were diagnosed by this program and many had associated co-morbidities at diagnosis. Our study shows that urine glucose testing is an inexpensive and simple test that allows for early diagnosis and treatment of T2DM in the primary care setting in this at risk population.

The motorcycle suspension system is one of the crucial components. It helps to support the motorcycle’s weight, isolate the vibration level caused by road imperfection, and keep the wheel in contact with the road surface. Therefore, the performance of suspension system needs to be enhanced to ensure the ride comfort and safety of riders. Coil spring is one of the essential parts of motorcycle suspension system. In this study, two different materials of coil spring are being focused include steel alloy and carbon fiber reinforced plastic (CFRP). The geometry of the coil spring is the existing design in the market. The static structural analyses are carried out to determine the directional deformation of y-axis, equivalent stress and equivalent elastic stress analysis of the corresponding coil spring material. The obtained results are discussed. It is found that the steel coil spring has better performance for the existing coil spring design. The directional deformation, equivalent stress and equivalent elastic strain of steel coil spring are considered at the lower side, which is 0.029357mm, 2003MPa and 0.010051mm/mm respectively. In this study, it is observed that the number of turns of coil spring should be increased to enhance the performance of CFRP coil spring.

The occurrence of typhoon Herb in 1996 caused massive landslides in the Shenmu area of Taiwan. Many people died and stream and river beds were covered by meters of debris. Debris flows almost always take place in the Shenmu area during the flood season, especially in the catchment areas around Tsushui river and Aiyuzih river. Anthropogenic and natural factors that cause debris flow occurrences are complex and numerous. The precise conditions of initiation are difficult to be identified, but three factors are generally considered to be the most important ones, i.e. rainfall characteristics, geologic conditions and topography. This study proposes a simple and feasible process that combines remote sensing technology and multi-stage high-precision DTMs from aerial orthoimages and airborne LiDAR with field surveys to establish a connection between three major occurrence factors that trigger debris flows in the Shenmu area.

INTRODUCTION In all cases of suspected child abuse, accurate risk assessment is vital to guide further management. This study examined the relationship between risk factors in a risk assessment matrix and child abuse case conference outcomes. METHODS Records of all children hospitalised at United Christian Hospital in Hong Kong for suspected child abuse from January 2012 to December 2014 were reviewed. Outcomes of the hospital abuse work-up as concluded in the Multi-Disciplinary Case Conference were categorised as 'established', 'high risk', or 'not established'. All cases of 'established' and 'high risk' were included in the positive case conference outcome group and all cases of 'not established' formed the comparison group. On the other hand, using the Risk Assessment Matrix developed by the California State University, Fresno in 1990, each case was allotted a matrix score of low, intermediate, or high risk in each of 15 matrix domains, and an aggregate matrix score was derived. The effect of individual matrix domain on case conference outcome was analysed. Receiver operating characteristic curve analysis was used to examine the relationship between case conference outcome and aggregate matrix score. RESULTS In this study, 265 children suspected of being abused were included, with 198 in the positive case conference outcome group and 67 in the comparison group. Three matrix domains (severity and frequency of abuse, location of injuries, and strength of family support systems) were significantly associated with case conference outcome. An aggregate cut-off score of 23 yielded a sensitivity of 91.4% and specificity of 38.2% in relation to outcome of abuse categorisation. CONCLUSIONS Risk assessment should be performed when handling suspected child abuse cases. A high aggregate score should arouse suspicion in all disciplines managing child abuse cases.

The main objective of this study is to improve the quality of injection-molded lenses with the implementation of DMAIC procedures based on the Six Sigma approach. At first, critical-to-quality factors (CTQ) are determined according to customer requirements for quality. The causal factors for the lens properties are identified within the processing window being tested. Adopted for the analysis procedures, the Taguchi design-of-experiment method (DOE) is employed for screening pertinent process parameters in the injection process. After completing the DOE procedures, confirmation experiments are conducted with selected combinations of factors and levels. The experimental results show substantial improvement for the profile accuracy on molded lenses. As a further step, an optimal set of factors and levels are taken during the mass-production processing conditions. In conclusion, the Six Sigma approach can effectively improve the upper process capability index CPU from 0.57 to 1.75, i.e., 0.07 defects per million, without an upgrade of production equipment or an increase of production costs.

The degradation of CrN films was investigated over temperatures of 400–1200 °C in air, nitrogen, and forming gas (N2/H2=9) by analyzing changes in color and appearance, as well as microstructures. The degradation mainly included color changes and cracks occurring on the film surface. The color change resulting from low-temperature/short-time annealing was due to the formation of an additional Cr2N phase, as well as a thin oxide overlayer. The color change appearing at higher temperatures/longer times stemmed from the formation of a thicker Cr2O3 layer, whose content depended on the pN2/pO2 ratio in the atmosphere. The driving force of the oxidation was the Gibbs free-energy change for CrN and Cr2O3. Cracks that showed up at relatively high temperatures were attributed to the large thermal mismatch between the CrN film and Cr2O3 overlayer. The thermal stresses were calculated and discussed. The degradation diagrams were generated based on the above analyzed results.

Edible: By grafting natural peptide antagonists onto the cyclotide kalata B1, orally active peptides were engineered, which are potentially useful therapeutics for the treatment of inflammatory pain. For example, the entire loop 6 of kalata B1 was replaced with the peptidic bradykinin B1 receptor antagonist DALK (red in scheme) to obtain the cyclic bradykinin antagonist ckb-kal.

The physiological alpha-oxoaldehyde methylglyoxal binds and modifies arginine, lysine, and cysteine residues in proteins. The kinetics and mechanism of these reactions were investigated with N alpha-acetylamino acids and bovine serum albumin at pH 7.4 and 37 degrees C. The reaction of methylglyoxal with N alpha-acetylarginine involved the initial reversible formation of glycosylamine and 4,5-dihydroxy-5-methylimidazolidine derivatives, with further slow irreversible conversion to an imidazolone, N alpha-acetyl-N delta- (5-methyl-4-imidazolon-2-yl)ornithine. The imidazolone was fluorescent with an excitation lambda max value of 320 nm and an emission lambda max value of 398 nm. Methylglyoxal reacted reversibly with N alpha-acetyllysine to form glycosylamine and bisglycosylamine derivatives. Further reaction of these glycosylamines occurred to form brown, fluorescent oligomers that were not characterized. Methylglyoxal reacted rapidly and reversibly with N alpha-acetylcysteine to form the hemithioacetal adduct. The reaction of methylglyoxal with bovine serum albumin (BSA) at pH 7.4 and 37 degrees C involved the reversible and irreversible formation of methylglyoxal-BSA adducts. Irreversible modification of BSA occurred mainly on arginine residues to form imidazolone. The formation of methylglyoxal-modified proteins involves glycoxidation leading to advanced glycation end product-like fluorescence. It is expected to be increased in diabetes mellitus and may be linked to the development of diabetic complications.

Glyoxalase II was purified from human red blood cells. The purification factor was 83,300 and the yield was 24% or 1.7 micrograms/ml red blood cells. The purified protein was a monomer with a molecular mass of 29,200 Da and an isoelectric point of 8.3. The rate of hydrolysis of S-D-lactoylglutathione to reduced glutathione and D-lactate, catalysed by glyoxalase II, followed Michaelis-Menten kinetics where the Km and kcat values were 146 +/- 9 microM and 727 +/- 16 s-1, respectively in 50 mM Tris/HCl, pH 7.4 at 37 degrees C. Other S-2-hydroxyacylglutathione derivatives were also acceptable substrates. S-p-Nitrobenzoxycarbonylglutathione was a potent competitive inhibitor of glyoxalase II with a Ki value of 1.20 +/- 0.21 microM, and the hemithioacetal formed non-enzymically from the reaction of methylglyoxal with reduced glutathione was a weak competitive inhibitor with a Ki value of 834 +/- 98 microM.

Virus-associated hemophagocytic syndrome (VAHS) is a non-neoplastic, generalized histiocytic proliferation with prominent hemophagocytosis associated with a systemic viral infection. Although Epstein-Barr virus (EBV) is one candidate virus for this association, thorough serologic and molecular biologic studies to determine the presence of the viral infection have been lacking in many reports. Whereas elevated liver function tests are common findings in patients with VAHS, exudative ascites and abdominal lymphadenopathy are rare. We describe a case of EBV-AHS masquerading as lymphoma in which treatment with intravenous immunoglobulins was associated with complete clinical remission at 2 years and 6 months after the onset. Regardless of the exact mechanism responsible for ascites formation in VAHS, this case adds support to the possible involvement of EBV in patients with abdominal lymphadenopathy and ascites.

This paper presents an advanced ac drive system used in electric vehicles (EV's). The system consists of an induction motor, a PWM transistorized inverter, a variable ratio gear box and a controller. The special features of the drive system are discussed, with emphasis on the control strategy which can optimize the performance of the EV.