Efficient Downlink Channel Reconstruction for FDD Multi-Antenna Systems

In this paper, we propose an efficient downlink channel reconstruction scheme for a frequency-division-duplex multi-antenna system by utilizing uplink channel state information combined with limited feedback. Based on the spatial reciprocity in a wireless channel, the downlink channel is reconstructed by using frequency-independent parameters. We first estimate the gains, delays, and angles during uplink sounding. The gains are then refined through downlink training and sent back to the base station (BS). With limited overhead, the refinement can substantially improve the accuracy of the downlink channel reconstruction. The BS can then reconstruct the downlink channel with the uplink-estimated delays and angles and the downlink-refined gains. We also introduce and extend the Newtonized orthogonal matching pursuit (NOMP) algorithm to detect the delays and gains in a multi-antenna multi-subcarrier condition. The results of our analysis show that the extended NOMP algorithm achieves high estimation accuracy. Simulations and over-the-air tests are performed to assess the performance of the efficient downlink channel reconstruction scheme. The results show that the reconstructed channel is close to the practical channel and that the accuracy is enhanced when the number of BS antennas increases, thereby highlighting that the promising application of the proposed scheme in large-scale antenna array systems

The absorption and uptake of recombinant human follicle-stimulating hormone through vaginal subcutaneous injections - a pharmacokinetic study

<p>Abstract</p> <p>Background</p> <p>Follicle stimulating hormone (FSH) has been routinely used for ovulation induction. Because of rapid clearance of the hormone, FSH is commonly administered by daily intramuscular or subcutaneous injections in in-vitro fertilization (IVF). To reduce the number of visits to the clinic, an intermittent vaginal injection of rhFSH every 3 days employing the concepts of mesotherapy and uterine first-pass effect was invented and has successfully been applied in women receiving IVF treatment. This study was designed to monitor the pharmacokinetic pattern of rhFSH administered vaginally.</p> <p>Methods</p> <p>Twelve healthy women with regular ovulatory cycles were recruited. All volunteers received gonadotrophin-releasing hormone agonist to suppress pituitary function and were assigned to receive single dose recombinant human FSH (rhFSH, Puregon 300) either using conventional abdominal subcutaneous injection or vaginal subcutaneous injection in a randomized cross-over study. Serum samples were collected at pre- scheduled time intervals after injections of rhFSH to determine immunoreactive FSH levels. Pharmacokinetic parameters characterizing rate [maximal plasma concentrations (Cmax) and time of maximal plasma concentrations (tmax)] and extent [area under the plasma concentration-time curve (AUC) and clearance] of absorption of rhFSH were compared.</p> <p>Results</p> <p>Vaginal injection of rhFSH was well tolerated and no drug-related adverse reaction was noted. Our analysis revealed that tmax was significantly earlier (mean 6.67 versus 13.33 hours) and Cmax was significantly higher (mean 17.77 versus 13.96 IU/L) in vaginal versus abdominal injections. The AUC_0-∞ was 1640 versus 1134 IU·hour/L in vaginal and abdominal injections, respectively. Smaller plasma elimination rate constant (0.011 versus 0.016 hour-1), longer mean residence time (106.58 versus 70.47 hours), and slower total body clearance (292.2 versus 400.1 mL/hour) were also found in vaginal injection.</p> <p>Conclusion</p> <p>The vaginal injection mode elicited a rapid and highly extended absorption of rhFSH injected compared to conventional abdominal injection. These data indicate that the rate and extent of FSH absorption from the injection site can vary depending on the route of the FSH administration.</p

On the Significance and Predicted Functional Effects of the Crown-to-Implant Ratio: a Finite Element Study of Long-Term Implant Stability Using High-Resolution, Nonlinear Numerical Analysis

poster abstractBackground. As the use of short dental implants becomes increasingly popular, the effects of the crown-to-implant (C/I) ratio on stress and strain distributions remain controversial. Previous studies in literature disagree on results of interest and level of necessary technical detail. Purpose. The present study sought to evaluate the strain distribution and assess its functional implications in a single implant-supported crown with various C/I ratios placed in the maxillary molar region. Materials and Methods. A high-fidelity, nonlinear finite-element model was developed to simulate multiple clinical scenarios by laterally loading a set of single implants with various implant lengths and crown heights. Strain distribution and maximum equivalent strain were analyzed to evaluate the effects and significance of the crown height, implant length and C/I ratio. The consistency of predicted functional responses to resulting strain at the implant interface were analyzed by interface surface area. Results. Results were evaluated according to the mechanostat hypothesis to predict functional response to strain. Overloading and effects of strain concentrations were more prevalent with increasing C/I ratios. Overloading was predicted for all configurations to varying degrees, and increased with decreasing implant lengths. Fracture in trabecular bone was predicted for at least one C/I ratio and all implant lengths of 10 mm or less. Conclusions. Higher C/I ratios and lower implant lengths increase the biomechanical risks of overloading and fracture. Increasing C/I ratios augment the functional effects of other implant design factors, particularly implant interface features. Greater C/I ratios may be achieved with implant designs that induce less significant strain concentrations

Supported Zinc Oxide Photocatalyst for Decolorization and Mineralization of Orange G Dye Wastewater under UV365 Irradiation

To solve the environmental challenge of textile wastewater, a UV/ZnO photocatalytic system was proposed. The objective of this study was to prepare a photocatalytic system by utilizing both cold cathode fluorescent light (CCFL) UV irradiation and steel mesh supported ZnO nanoparticles in a closed reactor for the degradation of azo dye C.I. Orange G (OG). Various operating parameters such as reaction time, preparation temperature, mixing speed, ZnO dosage, UV intensity, pH, initial dye concentration, and service duration were studied. Results presented efficient color and total organic carbon (TOC) removal of the OG azo dye by the designed photocatalytic system. The optimal ZnO dosage for color removal was 60 g m−2. An alkaline pH of 11.0 was sufficient for photocatalytic decolorization and mineralization. The rate of color removal decreased with the increase in the initial dye concentration. However, the rate of color removal increased with the increase in the UV intensity. The steel mesh supported ZnO can be used repeatedly over 10 times without losing the color removal efficiency for 120 min reaction time. Results of Fourier transform infrared (FTIR) and ion chromatography (IC) indicated the breakage of N=N bonds and formation of sulfate, nitrate, and nitrite as the major and minor products. The observation indicated degradation of dye molecules

THE ANALYSES OF KNEE INTERNAL FORCE DURING PASSIVE REPETITIVE ISOKINETIC PLYOMETRIC TRAINING

Passive Repetitive Isokinetic (PRI) training was a novel method for improving sport performance (Chiang Liu et al, 2005). As you know it can comprehensively advance muscular power characteristic of an athlete (Hsiang-Hsin Wang et al, 2005). But did you ever think that PRP training program might cause sport injury. It is not clear how much training effect would cause injury. Especially knee joint would sustain the most internal force for lower extremity. Therefore, the purpose of this study is to investigate the effects of plymeric training on overuse injuries of the knee. The hypothesis is that the torque of knee joint variables will be greatly affected by injury

Novel Codon-optimization Genes Encoded in Chlorella for Triacylglycerol Accumulation

AbstractMicroalgae have been recognized as one of the potential resources for biodiesel production based on its fast growth or its high total lipid content depending on species. Expression of Kennedy pathway genes, which encodes GPAT, LPAAT, PAP, and DGAT for increasing the metabolic flux towards the TAG storage in Chlorella sp. from 20 to 46 wt% and total lipid accumulation from 35 to 60wt.% corresponding to each specific gene combination under autotrophy, compare to the wild type (vector only). The highest TAG content was found in cells expressing a quadruple-gene construct (GPAT-LPAAT-PAP-DGAT) in the Kennedy pathway, corresponding to 46wt.% of TAG and 60wt.% of total lipid content. This work provides the optimization of TAG production in Chlorella sp. can be achieved by manipulating the selected genes, in turns making commercially producing biodiesel practical