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Acoustic manipulation is a non-contact process that applies acoustic waves to immobilize particles into a specific region for a variety of potential applications. This provides an alternative way to address air ventilation requirements where building systems are becoming smarter and more efficient. Development of such a process within confined spaces can incorporate microscopic interactions to filter aerosol-based particulate matter (PM). In real-engineering conditions, it is hard to filter sub-micron particles (0.25–1.0 μm) than super-micron particles (> 2.5 μm) by using low-grade filters. The objectives of this work are twofold. First, we propose a new acoustic-driven pre-filtering device (i.e., a U-shaped resonant acoustic chamber) that can improve the working efficiency of low-grade filters for capturing such particles. Second, the device can optimize spatial homogeneity to enhance the removal efficiency of airborne particles under lower sound intensity requirements. The U-shaped acoustic-driven device in the form of a resonant chamber allows PM to reside at the pressure node of a standing wave. Experimental studies are conducted to verify the present design. The results show that an overall filtration efficiency of up to 89% for 1.0-μm airborne particles can be achieved when the acoustic-driven device is coupled together with a low-grade MERV-6 coarse filter. As a standalone device, the acoustic effect works well for the sub-micron particles with a filtration efficiency of up to 61% under a lower sound pressure level (116 dB) than as previously reported in the literature. In the analysis, we also discuss the performance dependence on frequency, sound pressure level and flow rate in terms of particle size distribution. The relevance of this research is a major step towards engineering an acoustic-based pre-filtering technique for developing future innovative ventilation solutions.

Summary Understanding the mechanisms of human pluripotent stem cells (hPSCs) specification, development and differentiation to gametes are useful for elucidating the causes of infertility and potential treatment. This study aims to examine whether hPSCs can be induced to DDX4 extracellularly expressing primordial germ cell-like cells (DDX4ec PGCLCs) and further into ovarian follicle stage in a combined in vitro and in vivo model. The transcriptional signatures show that these DDX4ec PGCLCs are characteristic of PGCs and express ovarian folliculogenesis markers. We also verify that keratin (KRT)-8 is highly expressed in the DDX4ec PGCLCs and plays a crucial role in germ cell migration. By co-culturing DDX4ec PGCLCs with human granulosa cells (GCs), these cells are further induced into ovarian follicle-like structures in a xenograft mice model. This approach can in the future design practical strategies for treating germ cell-associated issues of infertility., Graphical abstract, Highlights • hPSC-derived DDX4 PGCLCs participate ovarian follicle-like structure formation • Human granulosa cells as a niche environment are participating folliculogenesis • Keratin 8 plays an essential role in primordial germ cell migration, Molecular Biology; Cell Biology; Stem Cell Research; Developmental Biology

The purpose of this investigation is to understand the effect of FeO-CaO-SiO2-MgO-xAl2O3 slags with 12.0~26.0 wt.% Al2O3 content on dephosphorization of molten steel. The dephosphorization experiments of FeO-CaO-SiO2-MgO-xAl2O3 slags are evaluated by a heater of induction furnace at the temperature of 1823 K. The results show that the dephosphorization ability of FeO-CaO-SiO2-MgO-xAl2O3 slags significantly decreases with the increasing of Al2O3 content. The oxidative slag with 12.4 wt.% Al2O3 possesses the biggest dephosphorization ability (approximately 82.7%) in all conditions. When the Al2O3 content of oxidative slag increases from 12.4 to 25.7 wt.%, the dephosphorization ability decreases from 82.7% to 34.6%. P2O5 content of oxidative slag also decreases with the increasing of Al2O3 content. The X-ray diffraction (XRD) results reveal that the Fe-based slag with 12.4 wt.% Al2O3 contains the constituent phases of FexO and Ca2Al2SiO7. As the Al2O3 content of Fe-based slag is above 22.1 wt.%, the constituent phase of FeAl2O4 is generated. The energy-dispersive X-ray spectroscopy (ESD) results verify that the capacity of phosphorus of FeAl2O4 phase is the worst in all phases. The capacity of phosphorus for each phase is Ca2Al2SiO7 phase > FexO phase > (Fe,Mg)Al2O4 phase.

In this study, heating was used to lower the viscosity of CPO to an acceptable level. 60°C was found to be the optimum heating temperature for CPO to ensure smooth flow in the fuel system, but heating further up to 100°C did not improve the engine performance. A comparison between CPO and diesel in terms of engine performance, combustion characteristics and emission showed that the brake specific fuel consumprion (bsfc) for CPO was 13% higher at 400 kPa brake mean effective pressure (bmep), and the highest bmep achieved was 13.5% lower. However, CPO fuel gave a brake thermal efficiency. Combustion analyses indicated that CPO combustion produced a 7% higher peak pressure, a 3.3-degree earlier ignition and an 11.6-degree longer burning duration, but a 26% lower peak heat release rate. After 500 hours of running CPO, performance and power of the engine dropped even while running with diesel. With a 26% higher bsfc and a 20% lowe maximum bmep. Visual inspection of the dismantled engine parts discovered heavy carbon deposits but normal wear. Overhaul of the engine restored the power and performance.

A search is presented for the production of a pair of Higgs bosons, where one decays into two photons and the other one into a bottom quark–antiquark pair. The analysis is performed using proton–proton collision data at s=13TeV recorded in 2016 by the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9fb−1. The results are in agreement with standard model (SM) predictions. In a search for resonant production, upper limits are set on the cross section for new spin-0 or spin-2 particles. For the SM-like nonresonant production hypothesis, the data exclude a product of cross section and branching fraction larger than 2.0fb at 95% confidence level (CL), corresponding to about 24 times the SM prediction. Values of the effective Higgs boson self-coupling κλ are constrained to be within the range −11

Suboptimal physical activity levels and tolerance, poor motor skills and poor physical health are demonstrated in children with Autism Spectrum Disorder (ASD). We speculate that social interaction and communication deficits in children with ASD are two major factors that hinder these children from actively participating in group physical activities. While previous studies have demonstrated that exercise intervention improves motor skills and behavioral outcomes in children with ASD, these programs tend to focus only on a single sport, which may not cater to the interests of different children with ASD. In this protocol, a game-based exercise training program designed by a multi-disciplinary team (pediatrics, physical education and psychology) will be implemented by front-line healthcare providers trained following the train-the-trainer (TTT) model and subjected to validation. Using a randomized controlled trial design, the effectiveness of the game-based exercise program will be examined for 112 young children with ASD. These children were randomly assigned to two groups, which will be tested and trained in either one of the two arms of the waitlist conditions (control and intervention). The assessment of physical and psychological traits will be conducted at baseline (pre-test), at 16-weeks (post-treatment) and at 32-weeks (follow-up) of the program. Most of the interventions designed for ASD children target either their psychological traits or physical conditions, without bridging the two states. With the recognition of bidirectional relations between mental and physical health, the present game-based exercise program which includes multiple level of difficulties was developed to equip ASD children with the necessary skills for engaging in sustainable team sports or even professional sport training. The program, if effective, will provide an entertaining and engaging training for whole-person development among children with ASD. This study is registered with the Chinese Clinical Trial Registry ( ChiCTR-IOR-17011898 ). Registered 6th July 2017.

Typical state-of-the-art disaster management information systems (DMIS) cannot support responsive discovery and access of data and information needed to handle unforeseen emergencies. Adding semantics and relations to legacy data and transforming them to linked data (LD) can remove this limitation. The virtual repository presented in this article is a development environment for this purpose: It provides application developers with tools for incremental transformation of legacy data and information in the DMIS into LD as needed by the applications. The virtual repository also provides the applications with support for runtime access of LD created and maintained using its tools.

Background: Overweight, obesity, and cardiovascular disease risk factors are prevalent among firefighters in some developed countries. It is unclear whether physical activity and cardiopulmonary fitness reduce cardiovascular disease risk and the cardiovascular workload at work in firefighters. The present study investigated the relationship between leisure-time physical activity, cardiopulmonary fitness, cardiovascular disease risk factors, and cardiovascular workload at work in firefighters in Hong Kong. Methods: Male firefighters (n = 387) were randomly selected from serving firefighters in Hong Kong (n = 5,370) for the assessment of cardiovascular disease risk factors (obesity, hypertension, diabetes mellitus, dyslipidemia, smoking, known cardiovascular diseases). One-third (Target Group) were randomly selected for the assessment of off-duty leisure-time physical activity using the short version of the International Physical Activity Questionnaire. Maximal oxygen uptake was assessed, as well as cardiovascular workload using heart rate monitoring for each firefighter for four “normal” 24-hour working shifts and during real-situation simulated scenarios. Results: Overall, 33.9% of the firefighters had at least two cardiovascular disease risk factors. In the Target Group, firefighters who had higher leisure-time physical activity had a lower resting heart rate and a lower average working heart rate, and spent a smaller proportion of time working at a moderate-intensity cardiovascular workload. Firefighters who had moderate aerobic fitness and high leisure-time physical activity had a lower peak working heart rate during the mountain rescue scenario compared with firefighters who had low leisure-time physical activities. Conclusion: Leisure-time physical activity conferred significant benefits during job tasks of moderate cardiovascular workload in firefighters in Hong Kong.

The purpose of this study was to examine the effects of 8-week core training on core endurance and running economy in college athletes. Twenty-one male college athletes were randomly divided into 2 groups: a control group (CON) (n = 10) and a core training group (CT) (n = 11). Both groups maintained their regular training, whereas CT attended 3 extra core training sessions per week for 8 weeks. The participants were assessed before and after the training program using sensory organization test (SOT), sport-specific endurance plank test (SEPT) and 4-stage treadmill incremental running test (TIRT). Compared with the pre-test, significant improvements were observed in post-test SOT (78.8 ± 4.8 vs. 85.3 ± 4.8, p = 0.012) and SEPT (193.5 ± 71.9 s vs. 241.5 ± 98.9 s, p = 0.001) performances only in CT. In the TIRT, the post-test heart rate values were lower than the pre-test values in CT in the first 3 stages. In stage 4, the post-test oxygen consumption (VO2) was lower than that in pre-test in CT (VO2: 52.4 ± 3.5 vs. 50.0 ± 2.9 ml/kg/min, p = 0.019). These results reveal that 8-week core training may improve static balance, core endurance, and running economy in college athletes.

Aim To investigate the effect of orlistat on endothelial function in obese adolescents. Methods Single-blind 10-week controlled trial of 67 normolipidaemic obese adolescents randomised into three groups. Group 1 (diet alone), Group 2 (diet and orlistat), Group 3 (diet, orlistat and exercise). Endothelial function measured by flow-mediated dilatation (FMD) of the brachial artery, anthropometric parameters, blood pressure, fasting blood lipids, insulin and glucose levels were recorded at baseline and at 10 weeks. Results Sixty four subjects completed the study. Groups were comparable at baseline. FMD increased significantly with orlistat (Groups 2 and 3) but not in Group 1. Orlistat treatment resulted in significantly reduced bodyweight, body mass index (BMI), waist circumference, total and low-density lipoprotein (LDL) cholesterol levels. High-density lipoprotein cholesterol levels were unchanged. Triglyceride and insulin levels were significantly reduced in all three groups. The reduction in cholesterols did not correlate with reductions in weight and BMI. A slight reduction of body fat, both with and without orlistat treatment, correlated with reduction in BMI after adjustment for baseline values. Blood pressure was unaltered by orlistat. Calorie intake was reduced with orlistat, and the decrease noted in % fat and increase in % carbohydrate was significant only in those taking orlistat. The addition of exercise (Group 3 compared with Group 2) altered no parameter. Conclusions Orlistat improves endothelial function and reduces bodyweight, BMI, fasting total and LDL-cholesterol in obese adolescents when combined with dietary control. Improvement in endothelial function if maintained could reflect long-term cardiovascular benefit.

AIM To determine the benefits of a 10-wk resistance training programme on cardiovascular health in non-obese and active adolescents. METHODS This is a pragmatic randomised controlled intervention. The study was carried out in a Hong Kong Government secondary school. Thirty-eight lean and active boys and girls were randomised to either the resistance training group or the control group. Students in the resistance training group received in-school 10-wk supervised resistance training twice per week, with each session lasting 70 min. Main outcome measures taken before and after training included brachial endothelial dependent flow-mediated dilation, body composition, fasting serum lipids, fasting glucose and insulin, high sensitive C-reactive protein, 24-h ambulatory blood pressure and aerobic fitness. RESULTS The only training related change was in endothelial dependent flow-mediated dilation which increased from 8.5% to 9.8%. A main effect of time and an interaction (P < 0.005) indicated that this improvement was a result of the 10-wk resistance training. Main effects for time (P < 0.05) in a number of anthropometric, metabolic and vascular variables were noted; however, there were no significant interactions indicating the change was more likely an outcome of normal growth and development as opposed to a training effect. CONCLUSION Ten weeks of resistance training in school appears to have some vascular benefit in active, lean children.

Background and objective: The aim of this study was to investigate the aerobic capacity of children 3 years after they were diagnosed with severe acute respiratory syndrome (SARS). Methods: Twenty-seven patients who completed both pulmonary function and maximal aerobic capacity tests at 6 and 15 months after the acute illness were invited to return for reassessment. Results: Twenty-one patients (median age 18.2 years, interquartile range (IQR) 16.5–19.7) completed all investigations at 36 months. Pulmonary function was normal in all patients. Maximal aerobic capacity, peak oxygen pulse (peak VO2) and ventilatory anaerobic threshold showed significant improvements compared with values measured at 6 months in both boys and girls. In girls, ventilatory efficiency (ventilatory equivalents for oxygen and carbon dioxide) and perfusion of the lungs (end-tidal partial carbon dioxide pressure) had not increased further compared with the values measured at 15 months. Although peak VO2 improved further at 36 months in patients with or without persistent radiological abnormalities, the values were 68% (IQR 50–84) and 74% (IQR 60–99), respectively, of those for normal control subjects. Conclusions: There were improvements in aerobic capacity at 36 months in children affected by SARS; however, the measured values remained suboptimal.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. Although its aetiology and pathogenesis remain unclear, recent studies suggest that the dysfunction of granulosa cells may partly be responsible. This study aimed to use cDNA microarray technology to compare granulosa cell gene expression profiles in women with and without PCOS to identify genes that may be aetiologically implicated in the pathogenesis of PCOS. The study cohort included 12 women undergoing in vitro fertilization, six with PCOS and six without PCOS. Differential gene expression profiles were classified by post-analyses of microarray data, followed by western blot analyses to confirm the microarray data of selected genes. In total, 243 genes were differentially expressed (125 upregulated and 118 downregulated) between the PCOS and non-PCOS granulosa cells. These genes are involved in reproductive system development, amino acid metabolism and cellular development and proliferation. Comparative analysis revealed genes involved in the mitogen-activated protein kinase/extracellular regulated kinase (MAPK/ERK) signaling pathways. Western blot analyses confirmed that mitogen-activated protein kinase kinase kinase 4 and phospho-ERK1/2 were decreased in PCOS granulosa cells. This study identified candidate genes involved in MAPK/ERK signaling pathways that may influence the function of granulosa cells in PCOS.

Physical activity and sedentary behavior are central components of lifetime weight control; however, our understanding of dimensions of these behaviors in childhood is limited. This study investigated free-living activity pattern characteristics and the individual variability of these characteristics in 84 lean and obese Chinese children (7-9 y) during the school day and over the weekend. Activity pattern characteristics were established from triaxial accelerometry (StayHealthy RT3). Results indicated that children's free-living activity is characterized by many short-duration, low-intensity bouts of movement. Obese children take longer rest intervals between bouts and engage in fewer activity bouts both at school and at home. Intraindividual variability in activity patterns was low during school days but high for the rest intervals between bouts and number of activity bouts per day at the weekend. Finding ways to reduce the rest time between bouts of movement and increase the number of movement bouts a child experiences each day is an important next step., published_or_final_version

Summary Background Previous studies have shown that cytokine gene polymorphisms may confer susceptibility to psoriasis. Objectives To determine whether genetic polymorphisms of the cytokine genes might influence the development of psoriasis in Chinese patients in Taiwan. Methods DNA samples were obtained from 170 patients with psoriasis vulgaris (PV), 102 patients with psoriatic arthritis (PsA) and 210 control subjects. Using direct sequencing and microsatellite genotyping, we examined 28 polymorphisms in 11 cytokine genes including the interleukin (IL)-1α, IL-1β, IL-1 receptor antagonist, IL-4, IL-8, IL-10, IL-12B, IL-13, tumour necrosis factor (TNF)-α, TNF-β and interferon-γ genes. Genotypes of HLA-Cw*0602, killer cell immunoglobulin-like receptor (KIR) genes and major histocompatibility complex class I chain-related gene A (MICA) were also determined in patients with PsA. Results The patients with PV were more likely to carry the +4496G allele of the IL-12B gene (59·4% vs. 49·3%, P = 0·0067, Pc = 0·033). However, no significantly different allelic and genotypic distributions of the other analysed genes including IL-1β, TNF-α, TNF-β, KIR genes and MICA were found between the PV/PsA patients and controls. Moreover, no association was observed with disease onset, gender, peripheral arthritis or joint erosion. With regards to HLA-Cw*0602, its allele frequency was significantly increased in patients with early-onset PV (25·3% vs. 4·8%, P

Education is so strongly emphasized in the Chinese culture that academic success is widely regarded as the only indicator of success, while too much physical activity is often discouraged because it drains energy and affects academic concentration. This study investigated the relations among academic achievement, self‐esteem, school conduct and physical activity level. The participants were 333 Chinese pre‐adolescents (aged 8–12) in Hong Kong. Examination results and conduct grades were obtained from the school records. Global self‐esteem was measured with the Physical self‐description questionnaire (PSDQ), while physical activity patterns of the children were assessed with the Physical activity questionnaire for children (PAQ‐C). Results showed that high academic achievers consistently attained better school conduct marks. However, physical activity level was quite an independent entity that was related neither to academic achievement nor school conduct. Furthermore, regression analyses showed that only ...

BACKGROUND: Besides the HLA-Cw*0602 allele, the psoriasis susceptibility 1 candidate 3 (PSORS1C3) and corneodesmosin (CDSN) genes are two probable psoriasis susceptibility genes in the PSORS1 locus. The -79C, -26C and +246A alleles of the PSORS1C3 gene, the CDSN*971T allele, CDSN*TTC (619T-1236T-1243C) and CDSN*5 (619T-1240G-1243C) are strongly associated with psoriasis in the caucasian population. Until now, no haplotype study of the PSORS1C3 and CDSN genes has been documented in Chinese patients with psoriasis vulgaris. OBJECTIVES: We aimed to determine whether genetic polymorphisms of the PSORS1C3 and CDSN genes were associated with an increased risk of psoriasis vulgaris in Chinese patients in Taiwan. METHODS: We investigated the PSORS1C3 and CDSN genes for disease association by direct sequencing in 178 patients with psoriasis vulgaris and 203 control subjects. Genotyping for HLA-Cw*0602, alpha-helix coiled-coil rod homologue (HCR) gene and single nucleotide polymorphism (SNP) n.9 was also carried out using a sequence-based typing method. RESULTS: The PSORS1C3*582A allele, an SNP in the 3'-untranslated region of the PSORS1C3 gene, was a major psoriasis vulgaris susceptibility allele in the Chinese population, and the association was much stronger in patients with early-onset psoriasis vulgaris (22.3% vs. 6.9%, odds ratio = 3.87, P(c) =0.0000072). The frequencies of CDSN*TTC and CDSN*971T were also significantly increased in patients with early-onset psoriasis vulgaris. Moreover, PSORS1C3*582A, SNP n.9*C, Cw*0602 and HCR*WWCC were in near complete linkage disequilibrium (LD) with each other; in contrast, the LD with the CDSN gene was not so strong. SNP n.9*C-Cw*0602-PSORS1C3*582A-HCR*WWCC was a major susceptibility haplotype in patients with early-onset psoriasis vulgaris (P < 10(-7)) and this risk haplotype also carried CDSN*TTC and CDSN*971T. CONCLUSIONS: The PSORS1C3 and CDSN genes are important psoriasis susceptibility genes in Chinese patients with psoriasis vulgaris.

Summary Background Bullous pemphigoid (BP) is an autoimmune bullous disease mostly associated with autoantibodies to the hemidesmosomal BP autoantigens BP180 and BP230. High levels of interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, tumour necrosis factor (TNF)-α and interferon (IFN)-γ have been detected in skin lesions or sera of patients with BP. Cytokine gene polymorphisms may affect cytokine production and contribute to susceptibility to autoimmune diseases. Until now, no cytokine gene polymorphism study has been conducted on patients with BP. Objectives We aimed to determine whether the genetic polymorphisms of the cytokine genes might influence the development of BP. Methods DNA samples were obtained from 96 BP patients and 174 control subjects. Using direct sequencing and microsatellite genotyping, we examined 23 polymorphisms in 11 cytokine genes including the IL-1α, IL-1β, IL-1 receptor antagonist, IL-4, IL-6, IL-8, IL-10, IL-13, IL-4 receptor, TNF-α and IFN-γ genes. Results Although the BP patients were more likely to carry the −511T and −31C alleles of the IL-1β gene (P = 0·04), the significance disappeared after correction for multiple testing (Pc). There was complete linkage disequilibrium between the −511T and −31C alleles of the IL-1β gene. In female patients with BP, the associations with IL-1β (−511T) and (−31C) alleles were much stronger (68% vs. 40·6%, odds ratio = 3·11, Pc = 0·006). No significantly different allelic and genotypic distributions of other cytokine gene polymorphisms could be found between the patients with BP and controls. Moreover, no association with the extent of disease involvement (localized or generalized) was observed. Conclusions The IL-1β (−511) and (−31) polymorphisms were significantly associated with BP in women. The other genetic polymorphisms of cytokine genes that we analysed do not appear to be associated with BP susceptibility in our Chinese population.

A bead-elastic rod model for fiber motion simulation is proposed. This model includes the effects of elastic modulus and flexural rigidity of the fiber, thus, it can describe the elasticity and flexibility of the fiber. Mixed Euler–Lagrange approach is adopted to derive the governing equations for modeling the fiber motion in air flow. The two-way coupling is introduced so that it will give a more clear understanding on the interaction between the fiber and air. The proposed model is applied in a textile process to simulate a fiber motion in the nozzle of an air-jet spinning machine.

Two modeling methods are used to predict the tensile properties of air-jet spun yarns. A numerical simulation provides a useful insight into the flow characteristics and wrap ping formation process of edge fibers in the nozzle of an air-jet spinning machine. By analyzing the results of the numerical simulation, the effects of nozzle parameters on yarn tensile properties can be predicted. A neural network model provides quantitative predic tions of yarn tenacity. The effects of parameters on yarn tenacity are also determined by the neural network model. Excellent agreement is obtained between these two methods.

JetRing and JetWind techniques, which use air-jet nozzles to reduce yarn hairiness, are the latest innovations in spinning and winding of staple yarns. The reduction of yarn hairiness is investigated in this paper both numerically and experimentally. A two-phase air/fiber flow model is developed to simulate the wrapping of a protruding surface hair in the nozzle. The effects of nozzle pressure and jet orifice angle on yarn hairiness are studied by both theoretical predictions and experiments. The results show the consistency of the numerical and experimental study.

A two-phase flow model is developed to simulate the fiber motion in the nozzle of an air-jet spinning machine. The computational results coincide with the images captured by high-speed photography. Three parameters, the first nozzle pressure, the jet orifice angle, and fiber flexural rigidity, are discussed in terms of their influences on wrapper formation and, consequently, on yarn structure and yarn quality. The predictions of yarn tensile properties tally with the experimental results reported by several researchers.

The aim of the study was to evaluate and compare the image quality of the 3D TOF MRA acquired with a small FOV and low phase encodes with those MR angiographic images acquired with standard pulse sequence parameters. Twenty patients who were referred to our institution for MR imaging of the brain and strictly satisfied the selection criteria were included in this study. Apart from the routine protocol for MR imaging of the brain, 3D TOF MRA of the circle of Willis with a small FOV and a standard FOV were performed. The image quality of all MRA was evaluated by two independent observers who were blind to the pulse sequence parameters. From the standard FOV MRA, 22.5, 12.5, and 5% of the patients were graded as mild, moderate, and severe stenosis of the internal carotid artery, respectively. On the contrary, no apparent stenosis was observed from the small FOV MRA with low phase encodes. Regarding the reduction in MR artifacts and acquisition time achieved with the small FOV 3D TOF MRA with low phase encodes, this might be a useful MR angiographic technique to be used in routine clinical practice.

A CFD (computational fluid dynamics) model is developed to simulate the air flow patterns inside the nozzle of an air-jet spinning machine. The design parameters of the nozzle are related to the flow characteristics, so they affect yarn properties. Three parameters are discussed: The effect of nozzle pressure is significant. With increasing nozzle pressure, both the axial and tangential velocity in the nozzle increase, thus increasing the tensile properties of the yarn. However, it is not sensible to increase nozzle pressure to a very high level. The jet orifice angle affects flow characteristics in a complex way. It dramatically affects the axial velocity and the negative pressure at the jet inlet. The selection of a jet orifice angle is a compromise of several factors. Even though the influence of the jet orifice position on the flow structure is insignificant, its design must be optimized. This work demonstrates that CFD can be used to optimize the nozzle design to produce air-jet spun yarns with better properties.

Crude palm oil (CPO) is one of the vegetable oils that have potential for use as fuels for diesel engines. CPO is renewable, and is safe and easy to handle. However, at room temperature (30–32°C) CPO has a viscosity about 10 times higher than that of diesel. To lower CPO’s viscosity to the level of diesel’s viscosity, a heating temperature of at least 92 °C is needed. At this temperature, there is a concern that the close-fitting parts of the injection system might be affected. This study focused on finding out the effects of preheating of fuel on the injection system utilising a modified method of friction test, which involves injecting fuel outside the combustion chamber during motoring. Results show that preheating of CPO lowered CPO’s viscosity and provided smooth fuel flow, but did not affect the injection system, even heating up to 100 °C. Nevertheless, heating up to such a high temperature offered no benefits in terms of engine performance. However, heating is necessary for smooth flow and to avoid fuel filter clogging. Both can be achieved by heating CPO to 60 °C. Combustion analyses comparisons between CPO and diesel found that CPO produced a higher peak pressure of 6%, a shorter ignition delay of 2.6°, a lower maximum heat release rate and a longer combustion period. Over the entire load range, CPO combustion produced average CO and NO emissions that were 9.2 and 29.3% higher, respectively, compared with those from diesel combustion.

Previous studies of head-up tilt test have shown that testing at high degrees lacks specificity in children. We suspected that the high false positive rate might be related to the intravascular catheter and other maneuvers incorporated in the test and therefore studied the sensitivity and specificity of standing and HUT at 80 degrees without any invasive procedure and other maneuvers in children and adolescents. Twenty three patients (11.8+/-2.7 years) with recurrent typical neurally mediated syncope and 35 normal control children (11.6+/-3.0 years) underwent motionless standing for 15 min and tilting to 80 degrees for 30 min. Continuous finger arterial pressure monitoring and ECG were performed during the test. Eight (35%) of the 23 patients developed symptoms of near syncope during motionless standing. Thirteen (57%) of them had positive results at 80 degrees tilting for 30 min. The symptoms of syncope were not always corresponding to excessive haemodynamic changes. None of the controls developed any symptoms or excessive hemodynamic changes. Without intravascular instrumentation and other autonomic maneuvers, active motionless standing or HUT at 80 degrees for 30 min is highly specific but of limited sensitivity for the investigation of vasovagal syncope.

Objective Peripheral arterial disease (PAD) is a chronic occlusive disease mainly occurred in elderly adults. Arteriosclerosis obliterans (ASO) mainly occurring from small or medium sized arteries of the lower extremities is one of the most common causes of PAD. The gender-related differences of circulating risk factors in diabetic patients with ASO in China remain unknown. The aim of this study is to investigate the gender-related differences in the pattern of several potential risk factors between male and female patients with ASO and type 2 diabetes mellitus (T2D). Design and methods Clinical profiles and risk factors were analyzed in 323 Chinese patients with ASO and 112 patients were confirmed with T2D. Severities of limb ischemia were staged according to Fontaine classification. Results The significant inverse correlation was seen between the increased age and hemoglobin. The significant positive correlation was seen between the increased age, urea and creatinine both in the non-diabetic and diabetic male patients. The expression levels of hemoglobin significantly correlate with the classification of Fontaine clinical symptoms in Chinese male patients with T2D/ASO. Conclusion The study is the first report indicating that the gender-related differences of circulating risk factors are associated with T2D patients with ASO in China. Anemia in Chinese male patients with T2D/ASO may play an important role in peripheral arterial disease progression.

Two laboratory scale extended aeration treatment systems (EATS) were built to study their nutrient removal performance before and after the introduction of oxidation-reduction potential (ORP) controlled aeration. Effects of various ORP set points (40, 70, 110 and 180 mV) and zoning of the aeration tank (AT) were examined. Each system had a 901 aeration tank and the operating HRT and SRT were 20 h and 20 days, respectively. Synthetic wastewater was used and the F/M ratios ranged from 0.13 to 0.15 gCOD/gMLSS/d. All experimental runs including the control yielded a similar COD removal efficiency of 96.4 ± 0.4% and an effluent COD of 14.4 ± 1.3 mg. This indicates that ORP controlled aeration had no significant impact on the carbonaceous removal of the EATS. Very good nitrogen (N) and phosphorus (P) removal was obtained when there was a small anoxic selector (3.8 l) at the head of the AT and the tank zoned into a main ORP zone (72 l) followed by an aerobic zone (18 l). The selector was found very useful in the prevention and curing of bulking as well as in the removal of P. It effectively denitrified the nitrate from the return sludge stream and caused significant P release, that is important to subsequent P uptake in the ORP and aerobic zones. An optimum ORP set point of 110 mV was found. The aeration pattern was characterized by having an equal time length of aeration and non-aeration. The achievable total nitrogen (TN) removal was 93% with a residual TN of only 2.94 mg/l (N). Excellent P removal of 99.5 ± 0.1% was attained under an ORP set point range of 70–180 mV. P was reduced to 0.05 ± 0.01 mg/l (P) in the effluent.

A study was conducted to examine N and P removal by a laboratory-scale extended aeration treatment system employing oxidation-reduction potential (ORP) controlled aeration. The system was provided with a 90-L aeration tank. When ORP controlled aeration was applied, the aeration tank was divided into three zones, namely the ORP zone (45 L), the anaerobic zone (27 L) and the aerobic zone (18 L). An external anoxic selector of 3.8 L in volume was also added. An ORP set point of 70 mV was used for the ORP zone. The extended aeration treatment system operating without the ORP controlled aeration was used as the control. COD removal (97%) was not affected, but both N and P removal were enhanced significantly in the ORP reactor. Total N removal efficiency was increased from 49.1% (control) to 83.5%. Almost all P was captured (99%), leaving an average of 0.09 mg L −1 P in the effluent. The ORP reactor yielded a sludge P content of 3.1%, compared to only 1.8% for the control. This indicated luxury P uptake in ORP reactor. Very significant P release and denitrification were found in the anoxic selector. Fairly good simultaneous nitrification and denitrification had occurred in the ORP zone. However, P release was very limited in the anoxic zone. However, anoxic P uptake and nitrification were found in this zone. Low F/M bulking was observed in both the control and ORP operation before the installation of a selector. Bacterial Type 0041 was identified as the predominant bulking organism. For the Control, an aerobic selector cured the bulking problem in one sludge age while an anoxic selector fixed up the problem during the ORP operation.

The effect of large current forward-bias stress on bipolar transistor gain and noise characteristics was investigated. The combination of high currents and high temperatures produced gain degradations or failures of transistors from three technologies. Similarly the application of high currents and high temperatures produced changes in transistor noise characteristics. Specifically, in all transistors stressed, the low-frequency noise initially decreased. It was also observed in two technologies that the noise eventually increased again as the stress continued. Electromigration induced stress is believed to play an important role in these phenomena. The third technology eventually showed failures of the transistors due to electromigration produced open circuits. >

Deformation processes in solids, such as dislocation movements under plastic flow, crack propagation and void crushing, produce stress waves at ultrasonic frequencies, usually described as acoustic emission (AE), which can be detected by sensitive instruments and which are related to the severity and nature of the deformations. The paper discusses the characteristics of the stress waves and their variation with wear rates, wear regimes and friction forces, as determined during laboratory experiments on metallic specimens in relative sliding motion, both unlubricated and with elastohy-drodynamic lubrication. It is shown that there are systematic relationships between the acoustic emissions, the wear rates, the frictional work inputs and established tribological contact variables. The predominant frequencies of the emissions are also evaluated and considered in relation to the materials and wear conditions.

This paper proposes a novel technique to forecast day-ahead electricity prices based on Panel Cointegration (PC). The current researches on the electricity price forecasting focus on the analysis of unstable economic time series. However, due to the difference of the allocation of power resource and consumption in different regions, the time series of electricity consumption and sales price in a single region cannot contain all information in different regions. In view of the disadvantages of the time series, the panel data is introduced to investigate the long-term equilibrium relationship and the short-term adjustment relationship between electricity consumption and sales price in the paper. The fundamental and novel contribution of the paper is to apply the PC to forecast accurately in day-ahead energy market price. The whole forecasting framework shows the use of PC model in predicting price behavior. Results from the electricity market of PJM in year 2008 are reported.

To support real power transfers, the system operators of power market must ensure that voltage throughout the network is maintained within acceptable levels under normal and abnormal contingent conditions in order to prevent loss of loads and to keep system reliability. In a competitive power market environment, reactive power is procured as an essential ancillary service. Various methods of procurement of the reactive power supply are outlined in the paper in which the authors envisaged a probabilistic scheme be used to incorporate system risk into the procurement decision. Numerical results on its application to two scenarios illustrate the quantitative approach of the procurement scheme.

The hydrophobicity of biopsy specimens of gastric mucosa in 228 dyspeptic subjects undergoing diagnostic endoscopy was assessed by measuring the plateauadvancing contact angle of saline drops using a goniometer. Subjects with duodenal ulcers (n = 49) and gastric ulcers (n = 17) had significantly lower mean contact angles than controls (n = 124) without ulcer (57° in duodenal ulcer, 59° in gastric ulcer vs. 66° in controls; p

Body mass index (BMI) and waist circumference (WC) correlate with cardiovascular (CV) risk factors in childhood which track into adulthood. WC provides a measure of central obesity, which has been specifically associated with CV risk factors. Reference standards for WC, and for WC and BMI risk threshold values are not established in Chinese children.To construct reference percentile charts of WC, establish relationships between WC, BMI and other risk factors, and propose WC and BMI threshold values predictive of CV risk factors in Hong Kong ethnic Chinese children.Weight, height, waist and hip circumference were measured in 2593 (52% boys, 47% girls) randomly sampled Hong Kong school children aged 6-12 years. In 958 of these and 97 additional overweight children (n=1055), the relationships between WC, BMI, waist/hip and waist/height ratio and six age-adjusted CV risk factors (85% percentile levels of blood pressure (BP), fasting triglycerides, low-density lipoprotein (LDL) cholesterol, glucose and insulin levels, and15% percentile levels of high-density lipoprotein (HDL) cholesterol) were studied. Receiver-operating characteristic analysis was employed to derive optimal age-adjusted sex-specific WC and BMI thresholds for predicting these measures of risk.WC percentiles were constructed. WC correlated slightly more than BMI with CV risk factors and most strongly with insulin and systolic BP, but poorly or not with LDL and glucose. Optimal WC and BMI risk thresholds for predicting four of these six CV risk factors were ca. the 85th percentiles (sensitivities approximately 0.8, specificities approximately 0.87) with age-specific cutoff values in girls/boys from approximately 57/58 to approximately 71/76 cm and 17/18 to 22/23 kg/m(2).These are the first set of WC reference data for Chinese children. WC risk cutoff values are proposed which, despite a smaller waist in Chinese children, are similar to those reported for American children. WC percentiles may reflect population risk.

Available transfer capability (ATC) is not only a crucial technical index, but also a strong market signal. In this research, a variant primal-dual predictor-corrector interior point method is presented for the multi-objective optimization of ATC with consideration on both system stability and economic benefit in power market. This method can tackle various stability constraints such as thermal limits, static upper and lower limits, transient angle stability and dynamic voltage stability constraints, etc., and take into account certain economic factors such as social benefit maximization, so as to optimize both stability and economics. Besides the fast evaluation speed and acceptable accuracy, this method is insensitive to the scale of objective system, therefore suitable for the application on bulk systems. Simulation and analysis on two test systems validate the above advantages of this method. In addition, research on how to enhance ATC via FACTS devices is implemented as well. (20 pages)

It is important for system operators to make importance assessments of reactive power sources in an open access environment. This paper presents a novel approach based on risk theory to assess the relative importance of reactive power sources in electricity power markets. The importance of reactive power sources are ranked by their risk values. The probability of the output level of reactive power sources, the probability of system contingency and the impacts of output variation of reactive power sources are taken into account. Finally the feasibility and efficiency of the proposed method are verified on the New England system. (5 pages)

Integrated farm drainage management (IFDM) systems employ sequential reuse of water with biomass production to help control saline groundwater and improve the sustainability of arid land irrigated agriculture. Currently operating near Five Points, CA is a 640 acre IFDM demonstration project. Subsurface drainage water is reused to irrigate plants of increasing salt tolerance and produce crops which could be utilized in energy conversion. Combustion properties of biomass are influenced by the presence of chlorine, alkali and other metals, all of which may increase in concentration with drainage water reuse. Physical, chemical, structural, and fuel properties were determined for three species of biomass irrigated with saline drainage water, including two woods (Athel and Eucalyptus) and one grass (Jose Tall Wheatgrass). For each species, the as-harvested moisture content, heating value, proximate analysis (ash, volatiles, and fixed carbon), and concentration of acid-insoluble ash were determined. Wood and bark dry matter fractions were determined on both a volume and a mass basis along with apparent wood density. Structural carbohydrate fractions were found through NDF, ADF, and lignin determinations. Ultimate, ash, and water soluble alkali analyses and heavy metals and trace element concentrations were also conducted for each biomass species. Combustion fuel properties including ash volatilization, ash fusibility, and ash sulfur decomposition temperatures were determined. The Jose Tall Wheatgrass has high fouling potential for combustion systems, and the Athel exhibits high uptake of calcium and alkali sulfates.

In a competitive supply-side power market, conditional maintenance can help the generation utilities to reduce cost and gain more profit. In this paper, reliability-centered maintenance (RCM) analytical method is adopted. The reliability-based mathematical model for predicting the failures of the subsystems and components in the power plant is established, and the failure mechanism is studied. Software is developed to simulate the failures evolution and forecast their tendency. Based on the above and further ranking the weightiness of equipment whose status to be observed by FMECA (failure mode effects & criticality analysis), the power plant manager may choose appropriate condition monitoring and failure diagnosis apparatus for carrying out conditional maintenance. At the end of this paper, some suggestions on the reformation of equipment maintenance plan and pattern in China are proposed. In this paper, practical research on four 200 MW generation units of Junliangcheng power plant in China is implemented. The results show that it can efficiently help decreasing the cost on maintenance and hence improve the total benefit.

Ensuring transient security usually requires the re-dispatch of generators to eliminate potential transient instability after a contingency, but this has commercial implications in a power market. A further complication is that different candidate contingencies may motivate different re-dispatch strategies because the advanced generator group is different in each case, or the sensitivity of the stability margin to power exchanges between generators is different. The paper develops an approach that attempts to address all of these significant issues in deregulated competitive power systems.

This paper develops an algorithm for point of collapse method to compute the static voltage stability limit point. The point of collapse method, due to its special advantages, has attracted many attentions. However, as the dimension of its equations is almost twice the ordinary power flow equations and it is not easy to make use of the advantages of sparse matrix technique, it is difficult to apply the point of collapse method to large systems. An algorithm is proposed in this paper to solve these problems. Modifying a standard power flow program can develop the program. The performance of this method is found to be accurate and computational efficient.