Massive luminous red galaxies (LRGs) are believed to be evolving passively and can be used as cosmic chronometers to estimate the Hubble constant. However, different LRGs may be located in different ...environments. The environmental effects may limit the use of the LRGs as cosmic chronometers. We aim to investigate the environmental and mass dependence of the formation of 'quiescent' LRGs selected from the Sloan Digital Sky Survey Date Release 8 and to pave the way for using LRGs as cosmic chronometers. Using the population synthesis software STARLIGHT, we derive the stellar populations in each LRG through the full spectrum fitting and obtain the mean age distribution and the mean star formation history (SFH) of those LRGs. We find that there is no apparent dependence of the mean age and the SFH of quiescent LRGs on their environment, while the ages of those quiescent LRGs depend weakly on their mass. We compare the SFHs of the SDSS LRGs with those obtained from a semi-analytical galaxy formation model, and find that they are roughly consistent with each other if we consider the errors in the STARLIGHT-derived ages. We find that a small fraction of later star formation in LRGs leads to a systematical overestimation (~28 %) of the Hubble constant by the differential age method, and the systematical errors in the STARLIGHT-derived ages may lead to an underestimation (~ 16 %) of the Hubble constant. However, these errors can be corrected by a detailed study of the mean SFH of those LRGs and by calibrating the STARLIGHT-derived ages to those obtained independently by other methods. The environmental effects do not play significant role in the age estimates of quiescent LRGs, and the quiescent LRGs as a population can be used securely as cosmic chronometers.
Transmission of videos in error prone environments may lead to video corruption or loss. Therefore error concealment at the decoder side has to be applied. Commonly error concealment techniques make ...use of the surrounding correctly received image data or motion information for concealment. In this paper, a novel spatio-temporal boundary matching algorithm (STBMA) by exploiting both spatial and temporal information to reconstruct the lost motion vectors (MV) is proposed, and also introduce a new side smoothness measurement. By using the motion vector that is found by the proposed algorithm, the lost macro block (MB) can be recovered. Compared with the well known boundary matching algorithm (BMA), the proposed algorithm is able to achieve higher PSNR as well as better visual quality.
In this paper, a spatial co-occurrence matrix (SCM) is proposed for representing the spatial relationship of semantic objects in images. The proposed SCM is established on both vertical and ...horizontal directions of interesting objects from the prototype spatial arrangement in images. The spatial relationships among objects can be retained directly in the prototype spatial arrangements, and then implicitly embedded in the proposed SCM. Furthermore, the calculation of spatial similarity among images can be implemented by calculating the distance between the SCMs.
In this paper, a novel semantic video object extraction method that combines spatial and temporal segmentation via the morphology watershed algorithm. We segment image into primitive regions by ...applying watershed algorithm. Then, we adopt temporal segmentation for tracking semantic objects. Experiments are carried out to demonstrate the superior performance of the proposed method.
To explore the effective treatment regimen for osteoradionecrosis of temporal bone.
Twenty-seven patients with massive osteoradionecrosis in temporal bone were included and retrospectively analyzed, ...in which, 15 cases received surgery and the other 12 cases adopted non-surgical treatment.
In the surgery group, three cases died one year postoperatively and died of massive hemorrhage due to internal carotid blowout. One case died four years after surgery without clear cause of death, and two cases were lost to follow up. Out of the nine survivors, the follow up period ranged from four months to eight years (one was followed up eight years, one was followed up over four years, four were followed up two-three years, one was followed up over one year, one was followed up nine months, and one was followed up four months, respectively). Patients classified as the type III received best outcome, and patients of type V and IV without invasion of the internal carotid artery received good surgical effects, while patient
This paper is devoted to investigation on prediction analyzing of the electromagnetic interfering signal in communication systems. In this paper, we proposed the concept of mathematical model group, ...and discussed the problem from several aspects which is listed below: frequency band of the transmitter, clutter and harmonic model of the receiver, the radiation power of the receiver, the modulation envelope curve, the frequency selection curve of the receiver, the correction factor of frequency interval and frequency selection, the susceptibility threshold, and the interfering signal power. When the frequency of the clutter approached the affected receiver's working frequency f/sub R/, it would form a sort of interference which affect the receiver. If the complementary wave of the interference of FIM, RIM, TIM and SIM is less than -20 db, it could be regarded that no interference exists. Otherwise, it could be regarded that the interference exists, and some measure must be used to eliminate the interference.
The sweetpotato whitefly Bemisia tabaci is a highly destructive agricultural and ornamental crop pest. It damages host plants through both phloem feeding and vectoring plant pathogens. Introductions ...of B. tabaci are difficult to quarantine and eradicate because of its high reproductive rates, broad host plant range, and insecticide resistance. A total of 791 Gb of raw DNA sequence from whole genome shotgun sequencing, and 13 BAC pooling libraries were generated by Illumina sequencing using different combinations of mate-pair and pair-end libraries. Assembly gave a final genome with a scaffold N50 of 437 kb, and a total length of 658 Mb. Annotation of repetitive elements and coding regions resulted in 265.0 Mb TEs (40.3%) and 20 786 protein-coding genes with putative gene family expansions, respectively. Phylogenetic analysis based on orthologs across 14 arthropod taxa suggested that MED/Q is clustered into a hemipteran clade containing A. pisum and is a sister lineage to a clade containing both R. prolixus and N. lugens. Genome completeness, as estimated using the CEGMA and Benchmarking Universal Single-Copy Orthologs pipelines, reached 96% and 79%. These MED/Q genomic resources lay a foundation for future 'pan-genomic' comparisons of invasive vs. noninvasive, invasive vs. invasive, and native vs. exotic Bemisia, which, in return, will open up new avenues of investigation into whitefly biology, evolution, and management.
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