Finding noncoding RNA transcripts from low abundance expressed sequence tags

It has been proved that noncoding RNA （ncRNA） genes are much more numerous than expected. However, it remains a difficult task to identify ncRNAs with either computational algorithms or biological experiments. Recent reports have suggested that ncRNAs may also appear in the expressed sequence tags （EST＇s） database. Nevertheless, intergenic ESTs have received little attention and are poorly annotated owing to their low abundance. Here, we have developed a computational strategy for discovering ncRNA genes from human ESTs. We first collected ESTs that are located in the intergenic regions and do not have detailed annotations. The intergenic regions were divided into non-overlapping 50-nt windows and PhastCons scores obtained from the UCSC database were assigned to these windows. We kept conserved windows that had PhastCons scores of over 0.8 and that had at least three supporting ESTs to act as seeds. Each cluster of ESTs corresponding to the seeds was assembled into a long contig. We used two criteria to screen for ncRNA transcripts from these contigs： the first was that the longest predicted open reading frame was less than 300 nt and the second was that the likely Pol-II promoters exist within 2 000 nt upstream or downstream of the contigs. As a result, 118 novel ncRNA genes were identified from human low abundance ESTs. Of seven randomly selected candidates, six were transcribed in human 2BS cells as shown by RT-PCR. Our work proves that the EST is a ＇hidden treasure＇ for detecting novel ncRNA genes.

THE COMPUTATION OF PARTIAL COHERENCE FUNCTION APPLIED FOR SOUND SOURCE IDENTIFICATION

In this paper, a new method is applied to get the computation formula of partial coherence function. The main attention is paid to the computation formula of the partial coherence function with three and four signals. The advantages of the method discussed in the paper are clear in physical meaning and easy to compute at the end of the paper,the application of the method to the identification of an air compressor noise source is presented and the results are satisfactory.

Optimal Data Transmission in Backscatter Communication for Passive Sensing Systems

Computational Radio Frequency IDentification (CRFID) is a device that integrates passive sensing and computing applications,which is powered by electromagnetic waves and read by the off-the-shelf Ultra High Frequency Radio Frequency IDentification (UHF RFID) readers.Traditional RFID only identifies the ID of the tag,and CRFID is different from traditional RFID.CRFID needs to transmit a large amount of sensing and computing data in the mobile sensing scene.However,the current Electronic Product Code,Class-1 Generation-2 (EPC C1G2)protocol mainly aims at the transmission of multi-tag and minor data.When a large amount of data need to be fed back,a more reliable communication mechanism must be used to ensure the efficiency of data exchange.The main strategy of this paper is to adjust the data frame length of the CRFID response dynamically to improve the efficiency and reliability of CRFID backscattering communication according to energy acquisition and channel complexity.This is done by constructing a dynamic data frame length model and optimizing the command set of the interface protocol.Then,according to the actual situation of the uplink,a dynamic data validation method is designed,which reduces the data transmission delay and the probability of retransmitting,and improves the throughput.The simulation results show that the proposed scheme is superior to the existing methods.Under different energy harvesting and channel conditions,the dynamic data frame length and verification method can approach the theoretical optimum.

Landmarks in the application of electrical tomography in particle science and technology

Selected milestones in the development and use of electrical tomography in powder conveying, slurry processing and multi-phase flow are highlighted. The ability to map concentration in opaque mixtures under process-realistic conditions was a major innovation for the method and has had far reaching implications. Subsequent developments have enabled velocity information to be abstracted resulting in the ability to measure component flux and motion.