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To investigate the effects of embryo abortion on fruit size and weight, fruit quality, chlorophyll, carotenoid, anthocyanin, flavonoid, and total polyphenols, the seeded fruit of mango (Mangifera indica L.) cultivar 'Guifei' were compared at the ripe stage. Seedless fruit had significantly smaller fruit size and lower fruit weight than seeded fruit in the cultivar. The experimental results suggested that embryo abortion at early stages of fruit ripening did not affect the concentration of total polyphenols in the pulp of matured fruit at green color or yellow color stages. However, the chlorophyll level decreased with ripening, lower in the abortion mango than in the normal mango. Carotenoid content increased throughout yellow stage and was significantly higher in the normal fruit compared to the abortion fruit. The concentrations of flavonoid were lower in the abortion fruit compared with normal fruit in the same color fruit. The expression of PSY and PDS was increased from green to yellow in abortion and normal mango. Expression of ANS and DFR was higher in the green color mango, in different development stages, and lower at the abortion stage in the yellow mango.

In order to study the stability of the output voltage of the linear switched reluctance generation (LSRG) for wave power system, three kinds of controllers are applied to track the output voltage of the system in this paper. The hardware structure and operation of the LSRG control system are introduced. The LSRG voltage control system is developed by the dSPACE control platform. The proportion integral differential (PID) controller, fuzzy PID controller and sliding mode controller are introduced in this article to conduct multiple experiments. The experimental results show that the voltage precision of the power generation system is relatively high under the fuzzy PID control scheme and an absolute error of ±0.2 v can be achieved.

Obstructed sleep apnea (OSA) is a common disorder which may need surgery to widen the airway; however the success rate of surgery is limited. Here we report a finding that could be used to predict the outcome of the OSA surgery. We found that inspiratory flow oscillates due to flow separation near the larynx, and the resulting periodic signal (3–5 Hz) is an intrinsic property of breathing. This flow oscillating signal may be the afferent stimulus to trigger respiratory events. It is found that the flow oscillation is attenuated for the OSA subjects. The computational fluid dynamics (CFD) simulation reveals that there exists flow separation near larynx and this separation is severely weakened in the OSA upper airway model. It is believed that the flow oscillating signal can serve as the measure to quantify the breathing quality of an OSA subject. This makes it possible to predict the surgery outcome of the OSA subject by applying CFD simulation.

The inspiratory flow characteristics in a CT-scanned human lung model were numerically investigated using low Reynolds number (LRN) kappa-omega turbulent model. The five-generation airway is extracted from the trachea to segmental bronchi of a 60-year-old Chinese male patient. Computations were carried out in the Reynolds number range of 900-2100, corresponding to mouth-air breathing rates of 190-440 ml/s. Flow patterns on the Re=2100 and flow rate distribution were presented. In this model, the flow pattern is very complex. To count the effect of laryngeal jet on trachea inlet, the trachea was extended and modified to simulate the larynx, consequently the inlet velocity profile is biased towards the rear wall. In the inferior lobar bronchi, there are two stems in which the axial velocity is stronger but secondary velocity is weaker. Secondary flow in the lateral bronchi is stronger than the medial ones. With increasing Re, the air flow increases in the middle, inferior lobes and left main bronchus, i.e., flow biases to left and downward.

One approach to tackle the particle deposition in human lungs in close proximity is to develop an understanding of the particle motion in bifurcation airways. Chronic obstructive pulmonary disease (COPD) is one of the most common diseases in humans. COPD always results in inflammation that leads to narrowing and obstructing of the airways. The obstructive airways can alter the respiratory flow and particle deposition significantly. In order to study the effect of obstruction on particle deposition, four three-dimensional four-generation lung models based on the 23-generation model of Weibel [1963. Morphometry of the Human Lung. New York Academic Press, Springer, Berlin.] have been generated. The fully three-dimensional incompressible laminar Navier-Stokes equations are solved using computational fluid dynamics (CFD) solver on structured hexahedral meshes. Subsequently, a symmetric four-generation airway model serves as the reference and the other three models are considered to be obstructed at each generation, respectively. The calculation results show that the obstructive airway has significant influence on the particle deposition down-stream of the obstruction. The skewed velocity profile in the bifurcation airway is modified by the throat; consequently, more particles impact on the divider which results in higher deposition efficiency.

Chronic obstructive pulmonary disease (COPD) is one of the most common diseases in human community. The COPD always results in inflammation that leads to narrowing and obstruction of the airways. The obstructive airways have significant effect on respiratory flow. In order to understand the flow phenomenon in such obstructive airways, four three-dimensional four-generation lung models based on the 23-generation model of Weibel [1963. Morphometry of the Human Lung. Springer, Academic Press, Berlin, New York] are generated. The fully three-dimensional incompressible laminar Navier-Stokes equations are solved using computational fluid dynamics (CFD) solver on unstructured tetrahedral meshes. Therein, a symmetric four-generation airway model is served as the reference, the other three models are considered to be obstructed at each generation, respectively. The calculation results show that the obstructive airway has significant influence on the air flow in both up- and down-stream airways and it even results in flow separation in the conjunction region. The re-circulation cell blocks the air from entering the downstream branches. This may be the reason why COPD patients should breathe gently, and this also provides some valuable information for medicine powder deposition.

Ni 0.5 Zn 0.5 Fe 2 O 4 –forsterite composites were synthesized by a sol–gel method. X-ray diffraction and SEM were used to characterize the crystallization behavior of the composite samples which were heat treated at temperatures varying from 800 to 1100°C. The results showed that Ni 0.5 Zn 0.5 Fe 2 O 4 and forsterite (Mg 2 SiO 4 ) can co-crystallize and the crystallites grow even more larger with increasing heat-treatment temperature. High-frequency (10 MHz–1 GHz) magnetic and dielectric properties of the composite samples were presented. Permeability increased with heat-treatment temperature. Quality factor was found to be two orders higher than that of equivalent pure, bulk ferrite.

Obstructive sleep apnea (OSA) is very common and can strike anyone at any age, even children. Yet still because of the lack of awareness by the public and healthcare professionals, the majority remain undiagnosed and therefore untreated, despite the fact that this serious disorder can have significant consequences. Untreated, sleep apnea can cause high blood pressure and other cardiovascular disease, memory problems, weight gain, impotency, and headaches [1]. OSA is caused by a blockage of the airway, usually when the soft tissue in the rear of the throat collapses and closes during sleep. With apnea event, the brain briefly arouses people with sleep apnea in order for them to resume breathing, but consequently sleep is extremely fragmented and of poor quality. Several surgical techniques may be used for OSA, and these include: uvulopalatopharngeoplasty (UP3), tonsillectomy and pharyngoplasty, uvulopalatal flap, laser and radiofrequency assisted uvulopalatal surgeries. The surgery involves removing the uvula and some of the surrounding soft palate. The idea behind the upper airway surgery is to eliminate the area of obstruction or to widen the airway so it does not occlude completely. However, the success rate is limited; for example, the UP3 helps in around 50% who have the surgery and in others it does not help at all or it helps only partially [2]. The post-operative complications after surgery are often the result of a dilemma during the operation of how much tissue to resect: too little is ineffective, yet too much may leave a patient with speech impedance and palatal stenosis, which can make OSA worse [3]. Therefore, accurate prediction of tissue reduction for this treatment is urgently needed.Copyright © 2011 by ASME

The particle deposition in human upper airway and lung airways were intensively studied. Most of the investigations considered the flow as steady, and the flow was either laminar or turbulent. However, the actually respiratory flow is strongly dependant on time, and the unsteadiness would affect the particle deposition significantly. In this study, we compared the respiratory flow and particle deposition in CT-scanned human upper airway with both steady and unsteady model in laminar regime. The result indicates that the unsteady effect has significant influence on flow and particle deposition in human upper airways.

The particle deposition in a computerized tomography (CT)-scanned human lung was numerically investigated. The five-generation airway is extracted from the trachea to segmental bronchi of a 60-year-old Chinese male patient. Computations were carried out in the flow rate range of 210-630 ml/s (Reynolds number range of 1000-3000) and particle size of 2-10 microm (Stokes number range of 0.0007-0.049). To count the effect of laryngeal jet on trachea inlet, the trachea was extended and modified to simulate the larynx, consequently the inlet velocity profile is biased towards the rear wall. The laryngeal jet-induced turbulence was simulated using low Reynolds number (LRN) kappa-omega turbulent model. Particle deposition patterns, deposition efficiency and deposition factor were studied in detail. The turbulent flow has significant effect on the particle deposition, and the present deposition factor is compared well with the available data.

A speech separation system has been built up that is self-supporting (i.e. does not require prior knowledge of pitch tracks obtained from the speech signals on their own as in the work of Stubbs and Summerfield, 1990), and is also robust to reverberation. A two-dimensional harmonic sieve that tracks harmonics in both amplitude and frequency has been developed. With the help sometimes of directional information in order to attribute the resulting pitch measurements to the appropriate speakers at times of pitch crossings or following breaks in voicing, reliable pitch tracking and accurate pitch extraction have been achieved in the present system. The present system can successfully extract one speech from mixed speech even when there are more than two overlapping speech signals. >

Obstructive sleep apnea (OSA) is a common disorder that may affect 3% of adult population in Hong Kong. This disorder can have serious consequences. OSA is caused by a blockage of the airway, in apnea event, the brain briefly arouses OSA subject in order for him/her to resume breathing, but consequently sleep is of extremely poor quality. Upper airway surgery is usually carried out for the treatment of OSA. The idea behind the upper airway surgery is to widen the airway so it does not occlude completely. However, the success rate is limited. The post-operative complications after surgery are often the result of a dilemma during the operation of how much tissue to resect: too little is ineffective, yet too much may make OSA worse (Van Lierde et al. 2002). Therefore, accurate prediction of tissue reduction for this treatment is urgently needed.

Catalysts selective for C2-oxygenates can be prepared based on rhodium. However, a support and/or promoter is essential. It is shown that with V2O3 as a support, selective catalysts are only obtained when during preparation (wet steps, high temperature reduction) species are formed which finally appear on the metal surface. Blocking of the Rh surface has been observed by IR spectra of adsorbed CO and by determination of the CO/Rh ratio. UV/VIS and ESR spectra show that by interaction of V2O3 with various chlorides or HCl, VOCl2·5H2O is formed. This compound can be reduced into VOCl which is rather stable. Selective catalysts can also be prepared by adding VOCl2 to a non-selective Rh/Aerosil catalyst.