In this letter, a direction-of-arrival (DOA) estimation method for the uniform-circular array (UCA) in the presence of gain-phase errors is proposed. Thanks to UCA properties, the virtual steering ...vector, which is constructed with the Hadamard product of the steering vector and its conjugate to eliminate phase errors, is considered to correspond to virtual 2-D sources impinging on the virtual UCA. This finding indicates that the azimuths and elevations of virtual sources, which are related to DOAs of original sources, can be decoupled and estimated via UCA-estimating-signal-parameter-via-rotational-invariance-techniques with the help of the recursive relationship of the Bessel function in the mode space of the virtual steering vector. We also propose the spatial filtering method, which is based on the linear independence of steering vectors in different directions, to eliminate one component in the virtual covariance matrix, which affects the DOA estimation of adjacent sources. This method can avoid the 2-D multiple-signal-classification search and cope with the one-component problem. Simulations verify its effectiveness.
The neurotransmitter histamine receives less attention compared with other biogenic amines, because of its moderate action in the central nervous system (CNS). However, recent evidence suggests that ...histamine plays an important role in multiple CNS disorders including insomnia, narcolepsy, Parkinson's diseases, schizophrenia, Alzheimer's disease, and cerebral ischemia. New insights are emerging into the potential roles of histamine receptors as targets for the treatment of these diseases. Although some histamine related agents have failed in clinical trials, current preclinical studies suggest that this neurotransmitter may still have extensive applications in treating CNS disorders, however, advanced studies are warranted. This review summarizes findings from animal models and clinical research on the role of histamine and its receptor ligands in the brain for treatment of CNS disorders. The development of novel histamine receptor ligands and gaining an in-depth understanding of their potential mechanisms are necessary stepping stones to unlock their wide-ranging applications in the clinical arena.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To investigate the seasonal characteristics of submicron aerosol (PM1) in Beijing urban areas, a high‐resolution time‐of‐flight aerosol‐mass‐spectrometer (HR‐ToF‐AMS) was utilized at an urban site in ...summer (August to September 2011) and winter (November to December 2010), coupled with multiple state of the art online instruments. The average mass concentrations of PM1 (60–84 µg m−3) and its chemical compositions in different campaigns of Beijing were relatively consistent in recent years. In summer, the daily variations of PM1 mass concentrations were stable and repeatable. Eighty‐two percent of the PM1 mass concentration on average was composed of secondary species, where 62% is secondary inorganic aerosol and 20% secondary organic aerosol (SOA). In winter, PM1 mass concentrations changed dramatically because of the different meteorological conditions. The high average fraction (58%) of primary species in PM1 including primary organic aerosol (POA), black carbon, and chloride indicates primary emissions usually played a more important role in the winter. However, aqueous chemistry resulting in efficient secondary formation during occasional periods with high relative humidity may also contribute substantially to haze in winter. Results of past OA source apportionment studies in Beijing show 45–67% of OA in summer and 22–50% of OA in winter can be composed of SOA. Based on the source apportionment results, we found 45% POA in winter and 61% POA in summer are from nonfossil sources, contributed by cooking OA in both seasons and biomass burning OA (BBOA) in winter. Cooking OA, accounting for 13–24% of OA, is an important nonfossil carbon source in all years of Beijing and should not be neglected. The fossil sources of POA include hydrocarbon‐like OA from vehicle emissions in both seasons and coal combustion OA (CCOA) in winter. The CCOA and BBOA were the two main contributors (57% of OA) for the highest OA concentrations (>100 µg m−3) in winter. The POA/ΔCO ratios in winter and summer are 11 and 16 µg m−3 ppm−1, respectively, similar to ratios from western cities. Higher OOA/Ox (= NO2 + O3) ratio (0.49 µg m−3 ppb−1) in winter study than these ratios from western cities (0.03–0.16 µg m−3 ppb−1) was observed, which may be due to the aqueous reaction or extra SOA formation contributed by semivolatile organic compounds from various primary sources (e.g., BBOA or CCOA) in Beijing. The evolution of oxygen to carbon ratio (O/C) with photochemical age allows to estimate an equivalent rate constant for chemical aging of OA in summer as kOH ~ 4.1 × 10−12 cm3 molecule−1 s−1, which is of the same order as obtained in other anthropogenic influenced areas and may be useful for OA modeling.
Key Points
PM1 concentrations are consistently high in recent years of Beijing (60 to 85 µg m−3)
Emission sources and formation pathways of aerosol in Beijing are seasonally different
Cooking as nonfossil OA source (13–24%) is important in Beijing
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
As a novel class of noncoding RNAs, circRNAs have been recently identified to regulate tumorigenesis and aggressiveness. However, the function of circRNAs in colorectal cancer (CRC) metastasis ...remains unclear. We aimed to identify circRNAs that are upregulated in CRC tissues from patients and study their function in CRC metastasis.
We compared six pairs of CRC tissues and their matched adjacent non-tumor tissues by using circRNA microarray. We first evaluated the expression of circPTK2 (hsa_circ_0005273) in fresh tissues from CRC tumors and corresponding adjacent tissues by qPCR analysis. CircPTK2 expression levels in the tissue microarray with 5 years of survival information were determined by RNA-ISH analysis. Meanwhile, the expression levels of circulating circPTK2 were further analyzed according to the patients' clinical features. We analyzed cell apoptosis, colony formation, migration, and invasion in CRC cells. To further elucidate the effect of circPTK2 in CRC metastasis, we also conducted a colon cancer hepatic and pulmonary metastasis experiment. We used RNA biotin-labeled pull down and mass spectrometry to identify the target of circPTK2. We established a PDTX model to evaluate the effect of shRNA specifically targeting circPTK2 on tumor metastasis.
We identified a novel circRNA, circPTK2, which is back-spliced of three exons (exons 27, 28 and 29) of PTK2 by using circRNA microarray, bioinformatics and functional studies. CircPTK2 was elevated in CRC tissues and positively associated with tumor growth and metastasis. CRC patients with increased circPTK2 expression were positively correlated with poorer survival rates. Furthermore, our studies showed that circPTK2 could promote EMT of CRC cells in vitro and in vivo by binding to vimentin protein on sites Ser38, Ser55 and Ser82. We further demonstrated the interaction of circPTK2 and vimentin mediated the regulation of CRC by knockdown or overexpression of vimentin. In addition, we revealed that tail vein injection of shRNA specifically targeting circPTK2 blunt tumor metastasis in a patient-derived CRC xenograft model.
Collectively, these results demonstrate that circPTK2 exerts critical roles in CRC growth and metastasis and may serve as a potential therapeutic target for CRC metastasis, and also a promising biomarker for early diagnosis of metastasis.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The network assignment image not only has a sharpness problem in the system audit but also the image angle deviates from the normal angle. Based on this, this study is based on image processing ...technology, using wavelet transform as the basic algorithm to process the image images collected by the network education system. At the same time, this study extracts the image content by wavelet transform in image edge recognition and enhances the image to enhance the image clarity. For the problem of image tilt, this study proposes a method of detecting the edge of the image with wavelet transform and then performing image tilt correction with Hough transform. In addition, this study compared the performance of the image correction method of this research and the traditional image method through experimental verification. Through comparative analysis, we can know that the performance of this research algorithm is better, and it can provide theoretical reference for subsequent related research.
Direction-of-arrival (DOA) estimation in the presence of gain-phase errors for uniform-circular-array (UCA) is addressed in this paper. Thanks to the uniformity and cycle property of UCA, the long ...data vector constructed with the proper entries of the Hadamard product of autocorrelation matrix and its conjugate, can be regarded as the received data corresponding to virtual two-dimensional sources impinging on virtual multiple UCAs. This finding indicates that azimuths and elevations of virtual sources related to DOAs of original sources can be decoupled and estimated via multiple-UCAs-estimating signal parameter via rotational invariance techniques proposed in this paper. Furthermore, two novel methods named as spatial-filtering-method and parameter-estimation-method are proposed to cope with one-component, which affects the DOA estimation of adjacent sources. Compared with the one-component elimination method proposed by Cao and Ye, previously mentioned two methods have closed-form solutions and they do not require iteration. The proposed method requires neither the calibration sources nor multidimensional parameter search. Furthermore, it can cope with more sources and work for various apertures of UCA. Simulations verify the effectiveness of the proposed method.
A Pt(IV) prodrug (2) composed of cancer-targeting biotin and nonsteroidal anti-inflammatory drug indomethacin in the axial positions of the six-coordinated octahedral geometry derived from cisplatin ...was developed, which could be highly accumulated in cancer cells more than normal ones and activated by endogenous reducing molecules to release cisplatin and indomethacin moieties simultaneously to inhibit tumor progression synergistically. In vitro assays revealed that 2 exhibited significantly selective inhibition to the tested cancer cell lines and sensitivity to cisplatin resistant cancer cells. Moreover, 2 presented cyclooxygenases inhibition properties to reduce tumor-associated inflammation, reduced the invasiveness of the highly aggressive PC-3 cells, and disrupted capillary-like tube formation in EA.hy926 cells. In all, this study offers a new strategy to enhance sensitivity and reduce toxicity of cisplatin.
Pt(IV) prodrug 2 highly accumulate in cancer cells than normal ones and activated by endogenous reducing molecules to release cisplatin and indomethacin simultaneously, exhibiting selective inhibition to cancer cell lines and sensitivity to cisplatin-resistant cancer cells. Moreover, this prodrug reduces the invasiveness of tumor cells and disrupts capillary-like tube formation. Display omitted
•Pt(IV) prodrug 2 composed of cancer-targeting moiety and anti-inflammatory drug•Prodrug 2 could be highly accumulated in cancer cells than normal ones.•Prodrug 2 selectively inhibits cancer cell lines.•Prodrug 2 sensitive to cisplatin resistant cancer cells•Prodrug 2 reduces invasiveness of tumor cells and disrupts capillary-like tube formation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
More and more evidence advises that circular RNAs (circRNAs) function critically in regulating different disease microenvironments. Our previous study found that autotransplantation of ...adipose-derived mesenchymal stem cells (ADSCs) promotes diabetes wound healing. Exosomes derived in ADSCs play an important regulatory role. This study aimed to characterize if mmu_circ_0000250 played a role in ADSC-exosome-mediated full-thickness skin wound repair in diabetic rats. Endothelial progenitor cells (EPCs) were selected to study the therapeutic mechanism of exosomes in high-glucose (HG)-induced cell damage and dysfunction. Analysis and luciferase reporter assay were utilized to explore the interaction among mmu_circ_0000250, miRNA (miR)-128-3p, and sirtuin (SIRT)1. The diabetic rats were used to confirm the therapeutic effect of mmu_circ_0000250 against exosome-mediated wound healing. Exosomes containing a high concentration of mmu_circ_0000250 had a greater therapeutic effect on restoration of the function of EPCs by promotion autophagy activation under HG conditions. Expression of mmu_circ_0000250 promoted SIRT1 expression by miR-128-3p adsorption, which was confirmed via luciferase reporter assay and bioinformatics analysis. In vivo, exosomes containing a high concentration of mmu_circ_0000250 had a more therapeutic effect on wound healing when compared with wild-type exosomes from ADSCs. Immunohistochemistry and immunofluorescence detection showed that mmu_circ_0000250 increased angiopoiesis with exosome treatment in wound skin and suppressed apoptosis by autophagy activation. In conclusion, we verified that mmu_circ_0000250 enhanced the therapeutic effect of ADSC-exosomes to promote wound healing in diabetes by absorption of miR-128-3p and upregulation of SIRT1. Therefore, these findings advocate targeting the mmu_circ_0000250/miR-128-3p/SIRT1 axis as a candidate therapeutic option for diabetic ulcers.
Rhamnogalacturonan I (RG-I) pectin is composed of backbone of repeating disaccharide units →2)-α-L-Rhap-(1→4)-α-D-GalpA-(1→ and neutral sugar side-chains mainly consisting of arabinose and galactose ...having variable types of linkages. However, since traditional pectin extraction methods damages the RG-I structure, the characteristics and health effects of RG-I remains unclear. Recently, many studies have focused on RG-I, which is often more active than the homogalacturonan (HG) portion of pectic polysaccharides. In food products, RG-I is common to fruits and vegetables and possesses many health benefits. This timely and comprehensive review describes the many different facets of RG-I, including its dietary sources, history, metabolism and potential functionalities, all of which have been compiled to establish a platform for taking full advantage of the functional value of RG-I pectin.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
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