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Introduction: The work was designed to investigate the effect of continuous positive airway pressure (CPAP) on hypertension in obstructive sleep apnea- hypopnea syndrome (OSAHS) patients and to elucidate the underlying mechanisms. Methods: We examined the effect of CPAP on blood pressure and biomarkers reflecting inflammation and oxidative stress, and investigated the correlation between changes in blood pressure and the biomarkers. Results: CPAP significantly improved clinic, ambulatory and home blood pressure (p < 0.05). The hypotensive effect of CPAP was positively correlated with the decrease of interleukin-6, C-reactive protein, NADPH oxidase and malonaldehyde. Conclusions: CPAP has a significant antihypertensive effect on OSAHS patients, especially nocturnal hypertension, possibly by counteracting inflammation and oxidative stress. [ABSTRACT FROM AUTHOR]

Cutting breeding is an important method of asexual reproduction of Xanthoceras sorbifolium Bunge. At present, it has been found that the factors influencing the cuttings of X. sorbifolium mainly include cutting material type, substrate type, cutting season, cutting material length and thickness, mother tree age, cutting material pretreatment method, hormone species concentration and soaking time. Besides, different regions, control conditions, and germplasm types have diferent cutting rooting rates. This paper introduced some of the problems in the cuttings of X. sorbifolium, and came up with some recommendations to provide a reference for the future research and technical promotion of X. sorbifolium cuttings. [ABSTRACT FROM AUTHOR]

In this paper a novel robust beamforming method is devised to receive multipath signals effectively. The new algorithm constructs a transformation matrix derived through high-order angle constraint to suppress the interferences with the directions of arrival (DOA) of interference signals. Using the transformed data, the composite steering vector of the multipath signals is estimated as the principal eigenvector of the signal subspace, and then is utilized in minimum variance distortionless response (MVDR) beamforming to compute the optimal weight vector. The new algorithm is improved in robustness to DOA error by forming wide nulls in incident directions of the interferences, and keeps effective in the presence of coherent interferences. Simulations analyses are provided to illustrate the robustness and effectiveness of the new beamformer. [ABSTRACT FROM AUTHOR]

The northern sea otter inhabits coastal waters of the northern Pacific Ocean and is the largest member of the Mustelidae family. DNA sequencing methods that utilize microfluidic partitioned and non-partitioned library construction were used to establish the sea otter genome. The final assembly provided 2.426 Gbp of highly contiguous assembled genomic sequences with a scaffold N50 length of over 38 Mbp. We generated transcriptome data derived from a lymphoma to aid in the determination of functional elements. The assembled genome sequence and underlying sequence data are available at the National Center for Biotechnology Information (NCBI) under the BioProject accession number PRJNA388419. [ABSTRACT FROM AUTHOR]

Frogs play important ecological roles, and several species are important model organisms for scientific research. The globally distributed Ranidae (true frogs) are the largest frog family, and have substantial evolutionary distance from the model laboratory Xenopus frog species. Unfortunately, there are currently no genomic resources for the former, important group of amphibians. More widely applicable amphibian genomic data is urgently needed as more than two-thirds of known species are currently threatened or are undergoing population declines. We report a 5.8 Gbp (NG50 = 69 kbp) genome assembly of a representative North American bullfrog (Rana [Lithobates] catesbeiana). The genome contains over 22,000 predicted proteincoding genes and 6,223 candidate long noncoding RNAs (lncRNAs). RNA-Seq experiments show thyroid hormone causes widespread transcriptional change among protein-coding and putative lncRNA genes. This initial bullfrog draft genome will serve as a key resource with broad utility including amphibian research, developmental biology, and environmental research. [ABSTRACT FROM AUTHOR]

Background: RNA-Sequencing (RNA-seq) is now commonly used to reveal quantitative spatiotemporal snapshots of the transcriptome, the structures of transcripts (splice variants and fusions) and landscapes of expressed mutations. However, standard approaches for library construction typically require relatively high amounts of input RNA, are labor intensive, and are time consuming. Methods: Here, we report the outcome of a systematic effort to optimize and streamline steps in strand-specific RNA-seq library construction. Results: This work has resulted in the identification of an optimized messenger RNA isolation protocol, a potent reverse transcriptase for cDNA synthesis, and an efficient chemistry and a simplified formulation of library construction reagents. We also present an optimization of bead-based purification and size selection designed to maximize the recovery of cDNA fragments. Conclusions: These developments have allowed us to assemble a rapid high throughput pipeline that produces high quality data from amounts of total RNA as low as 25 ng. While the focus of this study is on RNA-seq sample preparation, some of these developments are also relevant to other next-generation sequencing library types. [ABSTRACT FROM AUTHOR]

To understand implementation of a nationwide sloping farmland soil erosion comprehensive control project during China's 12th Five-Year Plan we used data collection and expert consultation. We selected 24 indexes across three aspects including project management, engineering construction and implementation benefit and used AHP-grey correlation analysis methods. We found that the scores for engineering construction were greater than 0.65 in most of the provinces, autonomous regions and municipalities. These scores are high and scores for project management and implementation benefit are between 0.45-0.65; however, overall scores are low. The comprehensive evaluation results are normally distributed. The composite scores for Sichuan, Yunnan and Guizhou are 0.71, 0.68 and 0.68 respectively, indicating that the implementation effects are good. The scores for Jilin and Liaoning are 0.38 and 0.42 respectively, indicating that the implementation effects need improvement. Scores for other provinces are between 0.45-0.65 and the effects are medium. The evaluation results show certain zonal rules spatially and the implementation effect in karst regions of Southwest China is the highest, followed by the purple soil region in Southwest China, Loess Plateau region of Northwest China, earth-rock mountain region of North China and red soil hilly region of South China. The implementation effect in the black soil region of Northeast China suggests that improvement is needed in this region. [ABSTRACT FROM AUTHOR]

The unique structure and extraordinary properties of carbon nanotubes make them a promising adsorbent for the removal of contaminants from aqueous solutions. In this study, the adsorption of remazol brilliant blue R (RBBR) from aqueous solutions onto carboxylated multi-walled carbon nanotubes (CCNTs) was investigated in a batch system. The influences of the initial pH value and the adsorbent concentration on the capacity of the CCNTs to adsorb the dye were studied. The adsorption isotherms were evaluated using the Langmuir and Freundlich adsorption isotherms, and the adsorption kinetics were investigated with pseudo-first-order and pseudo-second-order models. The optimal pH value for RBBR adsorption by CCNTs was 4.0 when the pH ranged from 4 to 9. The experimental data fitted the Langmuir isotherm model (R² > 0.990), and the maximum adsorption capacity of CCNTs for RBBR was 95.24, 103.63, and 109.41 mg/g at 25°C, 35°C, and 45°C, respectively. The RBBR uptake by the CCNTs was found to be rapid and almost reached equilibrium in 90 min. The kinetic data of the CCNTs followed a pseudo-second-order model (R² > 0.999). Thermodynamic studies were also performed to evaluate different parameters such as free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°). The adsorption process was found to be endothermic. The values of ΔH° and ΔS° were 44.91 and 0.192 kJ/mol, respectively, indicating that the adsorption process was chemisorption. The results demonstrate that CCNTs are very promising adsorbents for the effective removal of RBBR from aqueous solutions. [ABSTRACT FROM AUTHOR]

Background: Anaplastic thyroid carcinoma is the most undifferentiated form of thyroid cancer and one of the deadliest of all adult solid malignancies. Here we report the first genomic and transcriptomic profile of anaplastic thyroid cancer including those of several unique cell lines and outline novel potential drivers of malignancy and targets of therapy.Methods: We describe whole genomic and transcriptomic profiles of 1 primary anaplastic thyroid tumor and 3 authenticated cell lines. Those profiles augmented by the transcriptomes of 4 additional and unique cell lines were compared to 58 pairs of papillary thyroid carcinoma and matched normal tissue transcriptomes from The Cancer Genome Atlas study.Results: The most prevalent mutations were those of TP53 and BRAF; repeated alterations of the epigenetic machinery such as frame-shift deletions of HDAC10 and EP300, loss of SMARCA2 and fusions of MECP2, BCL11A and SS18 were observed. Sequence data displayed aneuploidy and large regions of copy loss and gain in all genomes. Common regions of gain were however evident encompassing chromosomes 5p and 20q. We found novel anaplastic gene fusions including MKRN1-BRAF, FGFR2-OGDH and SS18-SLC5A11, all expressed in-frame fusions involving a known proto-oncogene. Comparison of the anaplastic thyroid cancer expression datasets with the papillary thyroid cancer and normal thyroid tissue transcriptomes suggested several known drug targets such as FGFRs, VEGFRs, KIT and RET to have lower expression levels in anaplastic specimens compared with both papillary thyroid cancers and normal tissues, confirming the observed lack of response to therapies targeting these pathways. Further integrative data analysis identified the mTOR signaling pathway as a potential therapeutic target in this disease.Conclusions: Anaplastic thyroid carcinoma possessed heterogeneous and unique profiles revealing the significance of detailed molecular profiling of individual tumors and the treatment of each as a unique entity; the cell line sequence data promises to facilitate the more accurate and intentional drug screening studies for anaplastic thyroid cancer. [ABSTRACT FROM AUTHOR]

This research focused on the nutrient removal and the simultaneous CO2, CH4, and N2O emission rates of various combinations of vertical subsurface flow constructed wetlands (VSFCWs) and earthworm eco-filters (EEs) under different influent C/N ratios in synthetic wastewater. The optimal parameters for nutrient removal were influent C/N ratios of 5 : 1 and 10:1 as well as the combinatio n VSFCW-EE. Relatively low values of greenhouse gas (GHG) emission rates measured in situ were obtained at a C/N ratio of 5:1. The emission rates of CH4 and N2O were considerably lower than that of CO2. The VSFCW-EE and EEVSFCW combinations showed similar GHG emission results. The C/N ratio of 5:1 and the VSFCW-EE combination exhibited the highest nutrient removal efficiency with the lowest GHG emission rate. Wastewater nutrient removal and GHG emission were both high during summer (June to August) and low during winter (December to February). [ABSTRACT FROM AUTHOR]

Targeting cancers with amplified or abnormally activated c-Met (hepatocyte growth factor receptor) may have therapeutic benefit based on nonclinical and emerging clinical findings. However, the eventual emergence of drug resistant tumors motivates the pre-emptive identification of potential mechanisms of clinical resistance. We rendered a MET amplified gastric cancer cell line, GTL16, resistant to c-Met inhibition with prolonged exposure to a c-Met inhibitor, PF-04217903 (METi). Characterization of surviving cells identified an amplified chromosomal rearrangement between 7q32 and 7q34 which overexpresses a constitutively active SND1-BRAF fusion protein. In the resistant clones, hyperactivation of the downstream MAPK pathway via SND1-BRAF conferred resistance to c-Met receptor tyrosine kinase inhibition. Combination treatment with METi and a RAF inhibitor, PF-04880594 (RAFi) inhibited ERK activation and circumvented resistance to either single agent. Alternatively, treatment with a MEK inhibitor, PD-0325901 (MEKi) alone effectively blocked ERK phosphorylation and inhibited cell growth. Our results suggest that combination of a c-Met tyrosine kinase inhibitor with a BRAF or a MEK inhibitor may be effective in treating resistant tumors that use activated BRAF to escape suppression of c-Met signaling. [ABSTRACT FROM AUTHOR]

It is claimed that China's economic accomplishments have been ascribed to the adoption of the promarket land tenure reform characterized by granting individual households long-term land use rights. However, the increasing loss of farmland and its induced social conflicts, poverty, natural resource depletion, and poor governance explain the failure of the use of simplistic approaches as evidenced in other countries as well. China has not learned enough from those postsocialist countries in this regard. As land tenure is interwoven with social and political complexities, policy makers need to explore the underlying challenges of sustainable land use and governance in a greater depth. This article reveals the multifaceted nature of land tenure and its linkages with development and village governance. It proposes pro-poor land tenure as truly representing peasant needs for the design of more locally based institutional solutions that contribute to sustainable livelihoods, land use, and equitable development for the Chinese peasants. [ABSTRACT FROM AUTHOR]

Purpose: Gamma ray irradiation is considered as an effective way to degrade diclofenac. However, due to the extensive coexisting substances in natural waters, the use of gamma ray irradiation for degradation is often influenced by multiple factors. The various factors that affect degradation efficiency, such as initial diclofenac concentration, initial pH, and the concentration of the additives including HO (·OH radical promoter), CHOH (·OH radical scavenger), thiourea (·OH, H·, and e scavenger), humic acid, and NO (coexisting substances in natural waters), are investigated. Furthermore, possible intermediate products are identified and corresponding transformation pathways are proposed. Methods: Degradation experiments were performed in a 50-mL airtight Pyrex bottle loaded with 25 mL of diclofenac solutions at various initial concentrations of 20.5, 30.4, and 50.1 mg L. The radiation doses were controlled at 0, 0.3, 0.5, 0.7, and 1.0 kGy. Results: Study results indicate that: (1) The degradation efficiency of diclofenac decreases with the increase of its initial concentration. (2) The degradation efficiency is higher under acidic conditions than in neutral and alkaline media. (3) The results obtained when HO, CHOH, and thiourea were added show that the degradation of diclofenac takes place via two pathways: oxidation by ·OH radicals and reduction by e and H·. (4) The extensive coexisting substances in natural waters, such as humic acid and NO, do not affect the degradation efficiency. Based on the identified intermediates, it is proposed that transformation pathways are initiated mainly by H·, e, and ·OH. Conclusion: Gamma ray irradiation effectively degrades diclofenac. [ABSTRACT FROM AUTHOR]

The western black cottonwood ( Populus trichocarpa) was the first tree to have its genome fully sequenced and has emerged as the model species for the study of secondary growth and wood formation. It is also a good candidate species for the production of lignocellulosic biofuels. Here, we present and make available to the research community the results of the sequencing of the transcriptome of developing xylem in 20 accessions with high-throughput next generation sequencing technology. We found over 0.5 million putative single nucleotide polymorphisms (SNPs) in 26 595 genes that are expressed in developing secondary xylem. More than two-thirds of all SNPs were found in annotated exons, with 18% and 14% in regions of the genome annotated as introns and intergenic, respectively, where only 3% and 4% of sequence reads mapped. This suggests that the current annotation of the poplar genome is remarkably incomplete and that there are many transcripts and novel genes waiting to be annotated. We hope that this resource will stimulate further research in expression profiling, detection of alternative splicing and adaptive evolution in poplar. [ABSTRACT FROM AUTHOR]

The H3K9me3 histone modification is often found at promoter regions, where it functions to repress transcription. However, we have previously shown that 3' exons of zinc finger genes (ZNFs) are marked by high levels of H3K9me3. We have now further investigated this unusual location for H3K9me3 in ZNF genes. Neither bioinformatic nor experimental approaches support the hypothesis that the 3' exons of ZNFs are promoters. We further characterized the histone modifications at the 3' ZNF exons and found that these regions also contain H3K36me3, a mark of transcriptional elongation. A genome-wide analysis of ChIP-seq data revealed that ZNFs constitute the majority of genes that have high levels of both H3K9me3 and H3K36me3. These results suggested the possibility that the ZNF genes may be imprinted, with one allele transcribed and one allele repressed. To test the hypothesis that the contradictory modifications are due to imprinting, we used a SNP analysis of RNA-seq data to demonstrate that both alleles of certain ZNF genes having H3K9me3 and H3K36me3 are transcribed. We next analyzed isolated ZNF 3' exons using stably integrated episomes. We found that although the H3K36me3 mark was lost when the 3' ZNF exon was removed from its natural genomic location, the isolated ZNF 3' exons retained the H3K9me3 mark. Thus, the H3K9me3 mark at ZNF 3' exons does not impede transcription and it is regulated independently of the H3K36me3 mark. Finally, we demonstrate a strong relationship between the number of tandemly repeated domains in the 3' exons and the H3K9me3 mark. We suggest that the H3K9me3 at ZNF 3' exons may function to protect the genome from inappropriate recombination rather than to regulate transcription. [ABSTRACT FROM AUTHOR]

The article presents a study to determine the water sources in alpine ecosystem on the east Qinghai-Tibet plateau, China using stable isotopes. The result suggests that a major part of precipitation in alpine meadow was derived from secondarily evaporated water. It states that the precipitation on the east Qinghai-Tibet plateau was controlled by local water circulation in alpine ecosystems and the monsoon.

Analysis of DNA methylation patterns relies increasingly on sequencing-based profiling methods. The four most frequently used sequencing-based technologies are the bisulfite-based methods MethylC-seq and reduced representation bisulfite sequencing (RRBS), and the enrichment-based techniques methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylated DNA binding domain sequencing (MBD-seq). We applied all four methods to biological replicates of human embryonic stem cells to assess their genome-wide CpG coverage, resolution, cost, concordance and the influence of CpG density and genomic context. The methylation levels assessed by the two bisulfite methods were concordant (their difference did not exceed a given threshold) for 82% for CpGs and 99% of the non-CpG cytosines. Using binary methylation calls, the two enrichment methods were 99% concordant and regions assessed by all four methods were 97% concordant. We combined MeDIP-seq with methylation-sensitive restriction enzyme (MRE-seq) sequencing for comprehensive methylome coverage at lower cost. This, along with RNA-seq and ChIP-seq of the ES cells enabled us to detect regions with allele-specific epigenetic states, identifying most known imprinted regions and new loci with monoallelic epigenetic marks and monoallelic expression. [ABSTRACT FROM AUTHOR]

In alternative expression analysis by sequencing (ALEXA-seq), we developed a method to analyze massively parallel RNA sequence data to catalog transcripts and assess differential and alternative expression of known and predicted mRNA isoforms in cells and tissues. As proof of principle, we used the approach to compare fluorouracil-resistant and -nonresistant human colorectal cancer cell lines. We assessed the sensitivity and specificity of the approach by comparison to exon tiling and splicing microarrays and validated the results with reverse transcription-PCR, quantitative PCR and Sanger sequencing. We observed global disruption of splicing in fluorouracil-resistant cells characterized by expression of new mRNA isoforms resulting from exon skipping, alternative splice site usage and intron retention. Alternative expression annotation databases, source code, a data viewer and other resources to facilitate analysis are available at http://www.alexaplatform.org/alexa_seq/. [ABSTRACT FROM AUTHOR]

A bioreactor system consisting of a biotrickling filter and a bioscrubber united by nutrition liquid circulation was designed and used to treat methanethiol (MeSH), a common volatile organic compound produced in the petroleum industry. Chryseobacterium sp. JLL was added to the bioreactor to remove low-concentration MeSH. Results showed that the start-up and biofilm formation in the new bioreactor were much faster than those in the traditional deodorization bioreactor. Degradation of MeSH took place simultaneously in biotrickling filter and bioscrubbers of the combined bioreactor system after biofilm was formed. The optimized empty-bed residence time was found to be 60 s in the bioreactor. Under such a condition, the maximum MeSH elimination capacity was 50.8 g m−3 h−1, of which about 8–9 g m−3 h−1 was undertaken by the bioscrubbers and the rest removed by the biotrickling filter. The combined bioreactor system proved to be stable and durable in removal of MeSH-laden waste gas, showing its potential application in the treatment of various volatile organic compounds. [ABSTRACT FROM AUTHOR]

Background: Germ cells must progress through elaborate developmental stages from an undifferentiated germ cell to a fully differentiated gamete. Some of these stages include exiting mitosis and entering meiosis, progressing through the various stages of meiotic prophase, adopting either a male (sperm) or female (oocyte) fate, and completing meiosis. Additionally, many of the factors needed to drive embryogenesis are synthesized in the germ line. To increase our understanding of the genes that might be necessary for the formation and function of the germ line, we have constructed a SAGE library from hand dissected C. elegans hermaphrodite gonads. Results: We found that 4699 genes, roughly 21% of all known C. elegans genes, are expressed in the adult hermaphrodite germ line. Ribosomal genes are highly expressed in the germ line; roughly four fold above their expression levels in the soma. We further found that 1063 of the germlineexpressed genes have enriched expression in the germ line as compared to the soma. A comparison of these 1063 germline-enriched genes with a similar list of genes prepared using microarrays revealed an overlap of 460 genes, mutually reinforcing the two lists. Additionally, we identified 603 germline-enriched genes, supported by in situ expression data, which were not previously identified. We also found >4 fold enrichment for RNA binding proteins in the germ line as compared to the soma. Conclusion: Using multiple technological platforms provides a more complete picture of global gene expression patterns. Genes involved in RNA metabolism are expressed at a significantly higher level in the germ line than the soma, suggesting a stronger reliance on RNA metabolism for control of the expression of genes in the germ line. Additionally, the number and expression level of germ line expressed genes on the X chromosome is lower than expected based on a random distribution. [ABSTRACT FROM AUTHOR]

Ultra-high-throughput sequencing is used to show that distinct, localized patterns of nucleosome repositioning at promoters underlie the genome-wide transcriptional response to a physiological stimulus. [ABSTRACT FROM AUTHOR]

We developed a method, ChIP-sequencing (ChIP-seq), combining chromatin immunoprecipitation (ChIP) and massively parallel sequencing to identify mammalian DNA sequences bound by transcription factors in vivo. We used ChIP-seq to map STAT1 targets in interferon-γ (IFN-γ)–stimulated and unstimulated human HeLa S3 cells, and compared the method's performance to ChIP-PCR and to ChIP-chip for four chromosomes. By ChIP-seq, using 15.1 and 12.9 million uniquely mapped sequence reads, and an estimated false discovery rate of less than 0.001, we identified 41,582 and 11,004 putative STAT1-binding regions in stimulated and unstimulated cells, respectively. Of the 34 loci known to contain STAT1 interferon-responsive binding sites, ChIP-seq found 24 (71%). ChIP-seq targets were enriched in sequences similar to known STAT1 binding motifs. Comparisons with two ChIP-PCR data sets suggested that ChIP-seq sensitivity was between 70% and 92% and specificity was at least 95%. [ABSTRACT FROM AUTHOR]

Background: The embryonic definitive endoderm (DE) gives rise to organs of the gastrointestinal and respiratory tract including the liver, pancreas and epithelia of the lung and colon. Understanding how DE progenitor cells generate these tissues is critical to understanding the cause of visceral organ disorders and cancers, and will ultimately lead to novel therapies including tissue and organ regeneration. However, investigation into the molecular mechanisms of DE differentiation has been hindered by the lack of early DE-specific markers. Results: We describe the identification of novel as well as known genes that are expressed in DE using Serial Analysis of Gene Expression (SAGE). We generated and analyzed three longSAGE libraries from early DE of murine embryos: early whole definitive endoderm (0-6 somite stage), foregut (8-12 somite stage), and hindgut (8-12 somite stage). A list of candidate genes enriched for expression in endoderm was compiled through comparisons within these three endoderm libraries a nd against 133 mouse longSAGE libraries generated by the Mouse Atlas of Gene Expression Project encompassing multiple embryonic tissues and stages. Using whole mount in situ hybridization, we confirmed that 22/32 (69%) genes showed previously uncharacterized expression in the DE. Importantly, two genes identified, Pyy and 5730521E12Rik, showed exclusive DE expression at early stages of endoderm patterning. Conclusion: The high efficiency of this endoderm screen indicates that our approach can be successfully used to analyze and validate the vast amount of data obtained by the Mouse Atlas of Gene Expression Project. Importantly, these novel early endoderm-expressing genes will be valuable for further investigation into the molecular mechanisms that regulate endoderm development. [ABSTRACT FROM AUTHOR]

We analyzed 8.55 million LongSAGE tags generated from 72 libraries. Each LongSAGE library was prepared from a different mouse tissue. Analysis of the data revealed extensive overlap with existing gene data sets and evidence for the existence of ≈24,000 previously undescribed genomic loci. The visual cortex, pancreas, mammary gland, preimplantation embryo, and placenta contain the largest number of differentially expressed transcripts, 25% of which are previously undescribed loci. [ABSTRACT FROM AUTHOR]

A study on the potential and kinetics of hydrocarbon (HC) generation of 30 source-rock samples from a certain depression has been made by means of ROCK-EVAL technique. In the pyrolysis experiment, the source material types, maturation and hydrocarbon-generating potential of source rocks from three Upper Jurassic horizons of that area have been evaluated in terms of such indicators as the type-index, hydrocarbongenerating potential and maximum pyrolysis temperature (T). The results show that the pyrolysis HC yield of immature source rocks is much higher than that of mature rocks in case that the source material is of high quantity and organic matter is abundant, which suggests that it is important for evaluating the HC-generating potentiell to use immature samples for pyrolysis. In the pyrolytic simulation experiments on other two immature samples, it was found that the hydrocarbon yield is temperature-dependent, and thereafter the kinetical parameters for source rocks, such as reactional grade, appearant activation energy and frequency factor were calculated. [ABSTRACT FROM AUTHOR]

A novel beamformer without tapped delay lines (TDLs) or sensor delay lines (SDLs) is proposed. It treats one wideband signal from a direction as multiple narrowband signals from an angular sector. To preserve the signal of interest, it reconstructs the interference-plus-noise covariance matrix using narrowband Capon spectral estimator. Eliminating the TDLs and SDLs leads to a simpler system and lower computational complexity. Moreover, it outperforms traditional wideband beamforming methods in the case of limited snapshots or high signal-tonoise ratio. [ABSTRACT FROM AUTHOR]

A novel robust adaptive beamforming technique is proposed to solve the problem of performance degradation with one single snapshot. A sparse signal recovery model under the non-convex optimisation framework is first established, which dispenses with the mismatched sample covariance matrix, an indispensable part of most existing beamformers. Then, an iterative algorithm is designed to solve the optimisation problem by using the p-shrinkage operator and the alternating direction method of multipliers. The iteration steps are closed form and convenient to apply in practice. Simulation results demonstrate the effectiveness and robustness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

We present a method for data storage in continuous ferroelectric (FE) media, applicable to storage systems based on one or more scanning probes. Written FE domains are read back in a destructive fashion by applying a constant voltage of magnitude greater than the coercive voltage, as is done in FE random access memory (FeRAM). The resulting flow of screening charges through the readback amplifier provides sufficient signal to allow readback of domains of minimum dimension of the order of 10 nm at MHz rates, orders of magnitude faster than previously demonstrated techniques for readback of domains in continuous FE media. [ABSTRACT FROM AUTHOR]