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A deconvolution design for the 1/f fractal signal transmission systems is proposed. The design is based on multiscale Kalman deconvolution filter bank supplied in the analysis/synthesis wavelet filter bank. Wavelet transformation for 1/f fractal signal process is used as a multiscale whitening filter for removing the properties of self-similarity and long-range dependence from the fractal signals. An autoregression model is also proposed for the colored processes of the undecimated coefficients of multiscales.

In code-division multiple-access systems transmitting data over time-varying multipath channels, both intersymbol interference (ISI) and multiple-access interference (MAI) arise. In this paper, we address interference suppression, multipath diversity and processing gain protection for multiuser detection with less noise enhancement by using a parallel cancelling scheme. The proposed detector consists of RAKE filter, forward filter, and feedback filter with different functions for each filter. The RAKE filter increases the signal-to-noise ratio by taking the advantage of multipath and code diversities. The forward filter is proposed, in combination with the feedback filter, to remove the effects of MAI and ISI by parallel cancellation. In order to avoid performance deterioration due to unreliable initial estimation in the parallel cancellation, a cost function with proper weighting is introduced to improve the performance of the proposed detector. In the proposed design method, a recursive least square algorithm is employed to update the tap-coefficients of all filters for MAI and ISI cancellation. Finally, the performance of the proposed detector is analyzed and compared with other detectors. Index Terms--CDMA, multipath, fading channels, multiuser detection, parallel interference cancellations.

WUS plays an essential role in plant regeneration. To preliminarily understand the function of Gm- WUS, the related bioinformatics analysis was conducted based on the soybean database. GmWUS and AtWUS proteins were different in the acidic region, while other domains were conservative. Meanwhile, GmWUSa full - length sequence had been cloned. The protein mainly localized in the nucleus, showing that it might be a homeodomain transcription factor. The expression of GmWUS in cotyledons had been detected by qPCR during seeds germination. The results showed that both GmWUSa and GmWUSb expression levels kept rising, but GmWUSa expression decreased in the late stage. GmWUS expression in cotyledon node during cluster buds induction shown an approximate periodic pattern, indicating that GmWUS involved cluster buds diferentiation and regeneration. Comparing the expression of GmWUSa with GmWUSb, they might play a temporal complementary in their functions. The results in this study will help to investigate roles of GmWUS in soybean regeneration, to explain the mechanism of cluster buds formation, and to promote soybean regenerative capacity so as to improve the genetic transformation efficiency by overexpressing this gene. [ABSTRACT FROM AUTHOR]

Carbon microspheres (CMSs) were grafted onto the surface of wool fibers by microwave irradiation. The morphologies of wool fibers grafting CMSs were observed by Scanning Electron Microscopy ( SEM ) . The length and diameter of wool fiber was characterized. Thermal stability of wool fibers grafting CMSs was analysised by TG. The flame retardant properties of wool fibers were measured by the values of LOI (Limiting Oxygen Index). The results showed that the breaking strength of flame retardant wool fibers were increased by 3. 4% and the LOI value of flame retardant wool fiber was 29. 5% which could reach to 29. 2% even after repeat washing (at least 30 times). Compared with original wool fibers, modified wool fibers exhibited excellent flame retardant property. [ABSTRACT FROM AUTHOR]

Develops a scheme of parallel interference cancellers which includes a set of narrowband interference cancellation filters and a set of multiple access interference (MAI) cancellation filters to improve the signal-to-interference ratio and handle the MAI effect. Illustration of adaptive detector design; Presentation of two simulation examples to illustrate the performance of the proposed adaptive detector in direct-sequence code-division multiple access systems; Conclusion.

Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex (the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine (LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern.

Optogenetics is a new and rapidly evolving gene and neuroengineering technology that allows optical control of specific populations of neurons without affecting other neurons in the brain at high temporal and spatial resolution. By heterologous expression of the light-sensitive membrane proteins, cell type-specific depolarization or hyperpolarization can be optically induced on a millisecond time scale. Optogenetics has the higher selectivity and specificity compared to traditional electrophysiological techniques and pharmaceutical methods. It has been a novel promising tool for medical research. Because of easy handling, high temporal and spatial precision, optogenetics has been applied to many aspects of nervous system research, such as tactual neural circuit, visual neural circuit, auditory neural circuit and olfactory neural circuit, as well as research of some neurological diseases. The review highlights the recent advances of optogenetics in medical study.

Objective: To investigate the role of multidrug resistant protein 2 (MRP2) and glutathione (GSH) cotransport system in hepatic arsenic metabolism in rats., Methods: Thirty healthy Wistar rats were divided randomizedly into five groups. The first group was the control group and the rats in this group were administered with normal saline. In the second, third and fourth group the rats were administered with 4, 10 and 20 mg As(+)3/kg BW of sodium arsenite respectively every other day for two weeks. The fifth group was the benzene-soluble organics (BSO) intervention group and in this group the rats were administered with 2 mmol/kg BW BSO intraperitoneally every day three days before the end of the experiment. The other treatment was the same as in other groups. All rats were sacrificed two weeks after the treatments. Arsenic contents in bile, liver and blood were detected by atomic absorption spectroscopy (AAS), and the expression of MRP2 in the membrane of hepatocyte was determined by Western-blot analysis., Results: The level of total arsenic (including organic arsenic and inorganic arsenic) in bile, liver and blood in all three different dose groups was higher than those in the control groups (P < 0.05). Arsenic levels of bile and liver were increased with intragastric arsenic dose. Blood arsenic levels were not significantly different in three different dose groups. Expression of hepatic MRP2 was increased with intragastric arsenic concentration. A positive correlation between biliary arsenic concentration and MRP2 levels was found in liver (r = 0.986, P < 0.05). For the rats pretreated with BSO, the biliary arsenic was significantly higher than that in the control group but lower than that in the high dose group; the liver and blood arsenic was higher than that in the control group and in the high dose group. Expression of MRP2 pretreated with BSO was decreased., Conclusion: Sodium arsenite can induce expression of MRP2 and the up-regulation of MRP2 may play an important role in the bile secretion of arsenite and its metabolites. The function of MRP2 for transportation of arsenic and its metabolites is associated with the intracellular GSH level. BSO inhibits the synthesis of GSH, which weakens the function of the MRP2-GSH cotransport system and makes the liver arsenic increased.

This paper proposes a one-way micro valve with a simple structure and a simulation design for the engineering capsule. We have now got its design parameter selection method and its mechanic characteristic from experiments.

The swallowable camera-capsule,described in the aper, 11 mm in diameter and 30 mm in length , contains a CMOS image sensor, an optical system, a battery, a light source, a transmitter, a antenna and so on. The CMOS image sensor and its driving circuit can be miniaturized with MEMS technology. Image signal can be transmitted by analog or digital way. Image signal can be wirelessly transmitted through serial data interface. Finally, the processing technics of the capsule's crust is introduced.