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Wi-Fi fingerprinting has been a popular indoor localization due to the widespread layout of indoor WLAN. However, the signal fluctuations in the complex environments make it difficult to maintain high accuracy localization for the received signal strength (RSS) fingerprinting. Various positioning solutions have emerged to address this challenge, either working in stand-alone mode or in collaborative mode. In the former case, the user only utilizes his own RSS observation to request location service, while the latter usually requires information transfer between users. Considering the spatial correlation of wireless signal distribution, we propose an online joint localization scheme (JointLoc) that does not require direct interaction between users. The fact that the signals observed by users in physical proximity characterize the surroundings is used by JointLoc to identify neighboring users for joint localization. Besides this, JointLoc further integrates a novel subset-based localization scheme, thus the influence of anomalous RSS signals is eliminated before making the final location decision. We have fully evaluated the performance of JointLoc in two RSS datasets collected in real environments. Compared with conventional algorithms and the latest ones, results show that JointLoc is robust against signal fluctuations, and achieves good localization accuracy. [ABSTRACT FROM AUTHOR]

The surface color of cigar tobacco leaves (CTLs) is largely determined by the browning response and is one of the most important quality traits affecting consumer preferences. The physiological changes and metabolic network of browning in CTLs after harvest have not been reported. We investigated the molecular mechanism of browning in CTLs by comparing the physiological characteristics and metabolites of CTLs browning at five postharvest periods. Phenotypic traits and browning-related enzyme activity data indicated that the browning reaction was most intense at approximately 12 d when polyphenol oxidase and peroxidase activities reached their maximum. Postharvest CTLs polyphenols, polyacids, and carbon and nitrogen compounds were rapidly degraded during the yellowing phase, and the biosynthesis rate of polyphenols and carotenoids was greater than the degradation rate during the browning phase. Metabolomic analysis discovered 2027 metabolites that were annotated mainly to lipids and lipid-like molecules, organic acids and their derivatives, and organic heterocyclic components. Hierarchical cluster analysis discovered glutamate, serine, threonine, ornithine, and arginine as the major amino acids involved in the browning reaction. KEGG pathway enrichment analysis indicated that the metabolic pathways with important effects on enzymatic browning were phenylpropanoid biosynthesis, flavonoid biosynthesis, isoquinoline alkaloid biosynthesis, phenylalanine metabolism, and linoleic acid metabolism. The metabolic pathway network was mined, and the main polyphenols involved in the browning reaction of CTLs were found to be cyanidin, rutin, caffeoylquinic acid, kaempferol, naringin, and neohesperidin. This study provides a reference for the browning physiology and metabolism network of postharvest CTLs. [ABSTRACT FROM AUTHOR]

Leaf stacking fermentation involves enzymatic actions of many microorganisms and is an efficient and environmentally benign process for degrading macromolecular organic compounds. We investigated the dynamics of metabolite profiles, bacterial and fungal communities and their interactions during fermentation using cigar leaves from three geographic regions. The results showed that the contents of total sugar, reducing sugar, starch, cellulose, lignin, pectin, polyphenol and protein in cigar tobacco leaves was significantly decreased during fermentation. Notably, the furfural, neophytadiene, pyridine, benzyl alcohol, geranylacetone, 3-hydroxy-2-butanone, N-hexanal, 3-Methyl-1-butanol and 2,3-pentanedione were important features volatile aroma compounds during fermentation. The α-diversity of fungi and bacteria initially increased and then decreased during fermentation. An analysis of variance showed that microbial diversity was influenced by fermentation stages and growing locations, in which the all stages had greater impacts on α- and β-diversity than all regions. Microbiome profiling had identified several core bacteria including Sphingomonas, Bacillus, Staphylococcus, Pseudomonas, Ralstonia, Massilia and Fibrobacter. Fungal biomarkers included Aspergillus, Penicillium, Fusarium, Cladosporium and Trichomonascus. Interestingly, the molecular ecological networks showed that the core taxa had significant correlations with metabolic enzymes and physicochemical properties; bacteria and fungi jointly participated in the carbohydrate and nitrogen compound degrading and volatile aroma compound chemosynthesis processes during fermentation. These studies provide insights into the coupling of material conversion and microbial community succession during leaf fermentation. Key points: Furfural, neophytadiene, pyridine, benzyl alcohol, geranyl acetone, 2-butanone, 3-hydroxy-, N-hexanal, isoamylalcohol and 2,3-pentanedione were important features volatile aroma compounds. The Sphingomonas, Bacillus, Staphylococcus, Pseudomonas, Ralstonia, Massilia, Fibrobacter Aspergillus, Penicillium, Fusarium, Cladosporium and Trichomonascus play an important role in fermentation. The bacteria and fungi jointly participated in the the degradation of carbohydrate and nitrogen compounds in cigar tobacco leaves during fermentation. [ABSTRACT FROM AUTHOR]

With the aims of screening more antibacterial activity metabolites, in this study, two new (1 and 2), together with five known (3–7) isoquinolines were isolated from the cigar tobacco-derived endophytic fungi Aspergillus puniceus. Their structures were determined by means of HR-ESI-MS and extensive 1D and 2D NMR spectroscopic studies. The new compounds were evaluated for antibacterial activities against Pseudomonas syringae (the main pathogenic sources of tobacco angular leaf spot disease), and compounds 1 and 2 exhibited inhibitory effects with MIC50 values of 8.5 and 5.4 μg/mL respectively. These rates are lower than that of positive control (agricultural streptomycin, with MIC50 of 2.2 μg/mL). [ABSTRACT FROM AUTHOR]

Two new β-carboline alkaloids, 1-acetyl-6-hydroxymethyl-7-methoxy-β-carboline (1) and 1-acetyl-6- hydroxymethyl-8-methoxy-β-carboline (2), together with four known ones (3–6) were isolated from the cigar tobacco (a variety of Nicotiana tabacum L.)-derived endophytic fungi Aspergillus sp. Their structures were determined by means of HR-ESI-MS and extensive 1D and 2D NMR spectroscopic studies. The anti-TMV activities test revealed that compounds 1 and 2 showed potential anti-TMV activities with inhibition rates of 31.8 and 35.5%, respectively. These rates are close to that of positive control. Compounds 3–6 also showed anti-TMV activities with inhibition rates in the range of 21.5–28.8%, respectively. The isolation of the aforementioned β-carboline alkaloids may provide materials for the screening of anti-TMV activity inhibitors and contribute to the utilization of cigar tobacco-derived endophytic fungi. [ABSTRACT FROM AUTHOR]

With the aim of screening more antiviral activity metabolites, in this study, two new (1 and 2), together with five known (3–7), isoquinolines were isolated from the cigar tobacco-derived endophytic fungi Aspergillus fumigatus. Their structures were determined by means of HR-ESI-MS and extensive 1D and 2D NMR spectroscopic studies. Interestingly, the anti-TMV activities test revealed that compounds 1 and 2 showed potential anti-TMV activities with inhibition rates of 31.2 and 28.5%, respectively. [ABSTRACT FROM AUTHOR]

Background: The quality of cigar tobacco leaves was closely related to fermentation. To investigate the substance changes in cigar tobacco leaves during their fermentation, metabolomics was determined at different fermentation stages. In this study, the metabolic profile among different regions and fermentation periods of cigar tobacco leaf were evaluated. Results: A total of 1103 metabolites were identified in cigar tobacco leaf samples. A total of 293, 105 and 199 metabolites showed differential accumulation in the cigar tobacco leaf among different regions (PEF0 vs. LCF0, PEF0 vs. DHF0, PEF0 vs. YXF0) and 216, 242, 220, 227 and 198 metabolites showed differential accumulation in the different fermentation (LCF0 vs. LCF1, LCF0 vs. LCF2, LCF0 vs. LCF3, LCF0 vs. LCF4, LCF0 vs. LCF5). The main upregulated compounds were flavonoids, phenolic acids and lignans and coumarins, and the main downregulated compounds were organic acids, phenolic acids and amino acids and derivatives in the fermentation comparison group. Conclusions: These results provide valuable information for accurately grasping the end time of fermentation and improve efficiency of cigar tobacco leaf fermentation. [ABSTRACT FROM AUTHOR]

The chromone alkaloids have attracted the widespread attention of chemists and biologists due to their complex structures and prominent bioactivities. With the aim of screening more antiviral activity metabolites, in this study, two new (1 and 2), together with five known (3–7) chromone alkaloids were isolated from the cigar-tobacco-leaf-derived endophytic fungi Aspergillus lentulus. Interestingly, the anti-TMV activities test revealed that compounds 2, 5, and 7 showed high anti-TMV activities with inhibition rates of 44.2%, 38.5%, and 40.2%, respectively. These rates are higher than that of the positive control. Compounds 1, 3, and 5 also showed potential anti-TMV activities with inhibition rates in the range of 28.4–31.8%, respectively. The isolation of the aforementioned chromone alkaloids may provide materials for the screening of anti-TMV activity inhibitors and contribute to the utilization of the cigar-tobacco-derived endophytic fungi. [ABSTRACT FROM AUTHOR]

In this paper, we propose two hybrid inertial CQ projection algorithms with line-search process for the split feasibility problem. Based on the hybrid CQ projection algorithm, we firstly add the inertial term into the iteration to accelerate the convergence of the algorithm, and adopt flexible rules for selecting the stepsize and the shrinking projection region, which makes an optimal stepsize available at each iteration. The shrinking projection region is the intersection of three sets, which are the set C and two hyperplanes. Furthermore, we modify the Armijo-type line-search step in the presented algorithm to get a new algorithm.The algorithms are shown to be convergent under certain mild assumptions. Besides, numerical examples are given to show that the proposed algorithms have better performance than the general CQ algorithm. [ABSTRACT FROM AUTHOR]

Two new (1 and 2), together with four known (3–6) alkaloids were isolated from the whole plants of Thalictrum microgynum. Compounds 1–6 were tested for their anti-tobacco mosaic virus (anti-TMV) activity. The results indicated that compounds 2–4 showed high anti-TMV activity with inhibition rates of 34.8, 42.1, and 35.2% at a concentration of 20 μM, respectively. These rates were higher than that of ningnanmycin, a positive control. Compounds 1, 5, and 6 also showed potential anti-TMV activity with inhibition rates of 26.7, 24.8, and 28.2%. [ABSTRACT FROM AUTHOR]

Copyright of Frontiers of Information Technology & Electronic Engineering is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Considering the poor electronic conductivity of the pure Li9V3(P2O7)3(PO4)2, we have successfully synthesized a series of Li9−xMgxV3(P2O7)3(PO4)2 solid solution by aliovalent metal Mg ion doping on Li site. Due to the introduction of extra electrons caused by partially substituting Li+ ions by Mg2+, the electronic conductivity of the Mg-doped Li9V3(P2O7)3(PO4)2 sample was improved from 3.20×10−7 (for pure sample) to 8.85×10−6 S cm−1 (for Mg-doped sample). However, the inactive Mg2+ occupied the Li+ site often prevent the diffusion of the lithium ions in the electrode material and excessive Mg doping will obviously deteriorate the electrochemical performance of the electrode material. Considering the combined effect of the electronic conductivity and the lithium-ion diffusion coefficient for the excellent electrochemical performance, the optimal Mg-doping amount is x = 0.01 in our experiment. Compared with the pure sample, the Li9−xMgxV3(P2O7)3(PO4)2 (x = 0.01) sample exhibited a significantly increased specific capacity at all density rates and the capacity retention, especially at high rates, almost keep 100%. In addition, using the in-situ X-ray diffraction (XRD) method, we explored the reaction mechanism of the Li9V3(P2O7)3(PO4)2 electrode material and observed the existence and reversibility of the new phase during charge/discharge process. [ABSTRACT FROM AUTHOR]

Copyright of Frontiers of Information Technology & Electronic Engineering is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Attributed to the realization of the multielectron transfers, with a stable 3D framework, Li9V3 (P2O7)3(PO4)2 is considered an excellent cathode material, which can reversibly extract/insert nearly 5 mol Li. However, the poor intrinsic electronic conductivity and the low lithium diffusion coefficient limited its practical electrochemical ability. Considering the poor intrinsic electronic conductivity of the pristine Li9V3(P2O7)3(PO4)2 compound, the introduction of one extra electron by replacing V3+ with aliovalent Mo4+ ions increases the concentration of the electronic charge carriers from Li9V3(P2O7)3(PO4)2 and thus improves the electronic conductivity. At the same time, the larger ionic radius of Mo4+ leads to the increasement of the cell volume of the Li9V3(P2O7)3(PO4)2 sample and thus facilitates Li+ transport into the structure. As a result, the electrochemical performances of the Li9V3(P2O7)3(PO4)2 were improved obviously by a small amount of Mo. Especially for the Li9V3-xMox(P2O7)3(PO4)2 (x = 0.02) sample, the electrode present the highest specific capacity herein and an excellent rate performance which is a promising cathode for lithium ion battery application. [ABSTRACT FROM AUTHOR]

Image hashing is an efficient technology for processing digital images and has been successfully used in image copy detection, image retrieval, image authentication, image quality assessment, and so on. In this paper, we design a new image hashing with compressed sensing (CS) and ordinal measures. This hashing method uses a visual attention model called Itti model and Canny operator to construct an image representation, and exploits CS to extract compact features from the representation. Finally, the CS-based compact features are quantized via ordinal measures. L2 norm is used to judge similarity of hashes produced by the proposed hashing method. Experiments about robustness validation, discrimination test, block size discussion, selection of visual attention model, selection of quantization scheme, and effectiveness of the use of ordinal measures are conducted to verify performances of the proposed hashing method. Comparisons with some state-of-the-art algorithms are also carried out. The results illustrate that the proposed hashing method outperforms some compared algorithms in classification according to ROC (receiver operating characteristic) graph. [ABSTRACT FROM AUTHOR]

To ensure the security of digital information, information needs to be stored and processed in the encryption domain during the cloud storage process, during which the user does not allow the cloud provider (CP) to access the image contents, and the CP must embed additional information in the image. Therefore, reversible data hiding in an encryption domain (RDHEI) has emerged. This paper presents an adaptive and separable multiary RDHEI method. First, the image is divided into two parts that consist of reference pixels and non-reference pixels. Next, we compute the prediction errors of the non-reference pixels, followed by a replacement of the original non-reference values with the computed prediction errors. Then, the entire image is encrypted with a specially designed stream cipher strategy so that the CP can embed additional information by modifying the prediction errors without knowing the original image. In addition, although our method vacates space before encryption, the CP can adaptively control the reserved space, unlike traditional RDHEI schemes which also vacate space before encryption. Because our method is separable, the embedded message can be extracted from both encryption and plaintext domains accurately. The experimental results demonstrate the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]

Reversible image authentication (RIA) is an emerging research field for image tampering operation detection. Tampered regions can be localized precisely by embedding an authentication code (AC) into each divided image block in advance. Once the image is identified as an authentic image, the original image can be recovered without any loss. Under these two preconditions, an efficient RIA scheme is proposed to further improve the detection precision of the final authentication results. Compared with existing methods, a uniform embedding strategy is adopted in this paper, in which one AC bit is embedded into each divided image block to ensure they have the same authentication capability. To improve the forgery localization precision, the block size is adaptively sought according to the embedding capacity of the image. In addition, during the image authentication process, the embedding parameters and location map information are verified to increase the process's rigorousness. The experimental results demonstrate the superiority of the detection precision of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel real-time scheme of separable reversible data hiding in encrypted images, which consists of image encryption, data embedding, data extraction and image recovery. In image encryption phase, the content owner divides the original image into a number of non-overlapping blocks and encrypts blocks by stream cipher and permutation. During the data embedding phase, the data hider classifies encrypted blocks into smooth region and complex region according to the threshold and replaces the MSB layer of a part of pixels in blocks of smooth region with the secret data. Then, the LSB layers of other pixels are collected and compressed to generate a room for embedding the secret data again. When the receiver receives the marked image, he can divide the marked image into blocks and decrypt them by the encryption key to obtain a similar image with good quality. If the receiver only has the data hiding key, he can classify the blocks into smooth region and complex region according to the threshold and extract the embedded data by the data hiding key. If the receiver has both encryption key and data hiding key, he can extract the embedded data from the marked image and recover the original image perfectly. The proposed scheme can achieve satisfactory quality of decrypted image and high embedding rate. Experimental results demonstrate the effectiveness and computational efficiency of our scheme. [ABSTRACT FROM AUTHOR]

In this paper, we propose two efficient compression schemes for digital images using an adaptive selection mechanism for vector quantization (VQ), side match vector quantization (SMVQ), and image inpainting. On the sender side, after the original image is divided into blocks, the compression is implemented block by block. In both schemes, blocks in pre-specified locations are first compressed by VQ. For each remaining block, the optimal compression method (for the first scheme, including VQ or inpainting, and for the second scheme, including VQ, SMVQ, and inpainting) is determined by computing the mean square error (MSE) between the original block and its inpainted result and then comparing it with a predefined threshold. If MSE is greater than the threshold, image inpainting continues to be used to compress the current block. Otherwise, the compression mode of VQ or SMVQ is selected to substitute image inpainting to maintain higher visual quality. With the assistance of transmitted indicator flags, the receiver side can execute the image inpainting and decompression successfully. Experimental results demonstrate the effectiveness and superiority of two proposed schemes. [ABSTRACT FROM AUTHOR]

This paper proposes a novel reversible data hiding (RDH) algorithm with differential compression (DC) in encrypted image, which has high embedding capacity. The key contributions are two sides. (1) An efficient block-based encryption scheme is developed for encrypting image. It can transfer spatial correlation between neighboring pixels of plaintext image into encrypted image. (2) The DC scheme is proposed to conduct compression of encrypted image. It can efficiently compress encrypted image by exploiting pixel correlation and vacate a large room for data embedding. Many experiments are conducted to evaluate the performance of our RDH algorithm. Comparisons illustrate that our RDH algorithm outperforms some state-of-the-art algorithms in embedding capacity and computational time. [ABSTRACT FROM AUTHOR]

The development of image decryption techniques means that some current encryption techniques that turn a secret image into a meaningless image are no longer safe. Recently, encrypting an image into another meaningful image has opened a new route to transmit the secret image. This paper proposes an improved image encryption approach to camouflage the secret image into another host image. The visual quality of the final camouflage image has been significantly improved by using a human visual system (HVS) model. First, the secret image is pre-encrypted with a specific image encryption method, e.g., chaotic mapping method, then the host image is decomposed by a lifting wavelet transform (LWT) to generate integral wavelet coefficients. The encrypted secret image is then adaptively adjusted to a narrower range to guarantee that the final camouflage image is within a reasonable interval. Next, by using a HVS model, each modified image pixel is embedded into the corresponding detailed coefficients through an adaptive allocation strategy. Specifically, for pixels with extremely high or low intensity or high texture complexity, more bits of the modified secret pixels are allocated to substitute for the corresponding bits of coefficients. Then the modified coefficients are retransformed back to generate the final camouflage image. The secret image can be losslessly recovered through reversal procedures. The experimental results demonstrate the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, a reversible data hiding scheme for digital images with high hiding capacity is proposed. Original image is segmented into smooth and rough regions based on local complexity. In order to achieve higher hiding capacity, we embed three bits into each pixel belonging to smooth region with lower local complexity and one bit is embedded into each pixel of rough region, which can effectively exploit more redundancy during data embedding compared with conventional methods of prediction error expansion (PEE). Additionally, the pixel selection mechanism is applied to reduce the number of shifted pixels, which leads to high visual quality of stego image. Experimental results show that, our scheme can achieve better rate-distortion performance than some of state-of-the-art schemes. [ABSTRACT FROM AUTHOR]

Image compression technique is widely used in multimedia signal processing. As a conventional lossy compression technique, block truncation coding (BTC) deserves further improvements to enhance its performance of compression. The improvements of BTC mainly focus on: 1) enhancing the quality of reconstructed image and 2) decreasing the bit rate. In this paper, an adaptive and dynamic multi-grouping scheme is proposed for the absolute moment block truncation coding (AMBTC), which is mainly based on an optimized grouping mechanism with the adaptive threshold setting according to the complexity of image blocks. Besides, the values of the reconstruction levels are replaced by their compressed difference values in order to decrease the bit rate. Experimental results demonstrate that the proposed scheme can enhance the compression performance of AMBTC effectively. [ABSTRACT FROM AUTHOR]

Estimating variances in noise is of key importance in many image processing applications, such as filtering, enhancement, quality assessment, and detecting forgery. For the existing detection methods that are based on inconsistencies in noise, the conventional approach is to estimate the noise variance of each region first and then identify the regions with extremely higher or lower variance as splicing regions. However, due to the impossibility of completely separating image noise and inherent texture, inevitably, each estimate is overestimated, especially for regions that have more complex textures. In this paper, we consider the issue that the estimation of the noise of each region frequently is inaccurate due to the complexity of the texture of the region. Based on this consideration and motivated by the scoring strategy-based, object-proposal technique, an approach that incorporates the inhomogeneity scoring strategy is proposed to provide a more convincing result to expose image-splicing manipulations. Specifically, first, the image is segmented into small patches, and the noise variance of each patch is computed by using the kurtosis concentration-based pixel-level noise estimation method. Then, the inhomogeneity score is computed using the spectral residual-based saliency measurement method. After using a linear equation fitting based on the estimated sample of variance and the inhomogeneity score of each patch, the suspicious region can be identified by seeking the conjunct patches that are out of the linear constraint. The experimental results demonstrated the efficacy and robustness of the proposed method. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the anti-inflammatory effect of hepatocyte growth factor (HGF) on pulmonary artery hypertension (PAH) in a rat model and underlying mechanisms. Wistar rats were treated with monocrotaline intravenously to induce PAH and then treated with vehicle or HGF for 2 weeks, respectively. The mean pulmonary artery pressure (mPAP), the index of right heart ventricular hypertrophy (RHVI), pathological changes, and inflammation in the lungs of individual rats were measured. The levels of serum inflammatory interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and high mobility group protein B1 (HMGB1) and the relative levels of IκBα and NF-κB p65 expression in the lungs of individual rats were determined by methods of enzyme-linked immunosorbent assay (ELISA) and Western blot. The levels of mPAP and RVHI in the HGF group were significantly lower than that in the PAH group (P < 0.05), but remained significantly higher than that of the control group (P < 0.05). Similar patterns of inflammatory scores and the levels of serum IL-6, TNF-α, ICAM-1, and HMGB1 were detected among the different groups of rats. Furthermore, the relative levels of IκBα expression in the lungs of the HGF group of rats were significantly higher than that in the control group, which were significantly higher than that in the PAH group. In contrast, the relative levels of NF-kB p65 expression in the HGF group were significantly lower than that in the PAH group (P < 0.05). HGF treatment significantly mitigated the severity of PAH and inhibited inflammation by attenuating the NF-kB signaling in the lungs of PAH rats. [ABSTRACT FROM AUTHOR]

NH4Cl corrosion failure often occurs in the overhead systems of hydrotreaters, and this failure is always accompanied by the appearance of H2S. A combination of electrochemical and surface spectroscopic (SEM/EDS, AFM, XRD) techniques was used to investigate the effect of different factors, including the surface roughness, temperature, dissolved oxygen, pH and H2S concentration, on the corrosion behavior of carbon steel in an NH4Cl environment with the presence of H2S. The effect of H2S concentrations (at the ppm level) on the corrosion behavior of carbon steel was systematically revealed. The experimental results clearly indicated that the corrosion rate reached a minimum value at 10 ppm H2S. The steel surface was covered by a uniform corrosion product film in a 10 ppm H2S environment, and the corrosion product film was tight and protective. The ammonia from NH4Cl helped maintaining the protectiveness of the corrosion films in this environment. Dissolved oxygen mainly accelerated the cathodic reaction. The cathodic limiting current density increased with increasing temperature, and the anodic branch polarization curves were similar at different temperatures. The anodic current density decreased as the pH decreased, and the cathodic current density increased as the pH decreased. The absolute surface roughness (Ra) of carbon steel increased from 132.856 nm at 72 h to 153.973 nm at 144 h, and the rougher surface resulted in a higher corrosion rate. The critical innovation in this research was that multiple influential factors were revealed in the NH4Cl environment with the presence of H2S. [ABSTRACT FROM AUTHOR]

In a spliced image, areas from different origins contain different noise features, which may be exploited as evidence for forgery detection. In this paper, we propose a noise level evaluation method for digital photos, and use the method to detect image splicing. Unlike most noise-based forensic techniques in which an AWGN model is assumed, the noise distribution used in the present work is intensity-dependent. This model can be described with a noise level function (NLF) that better fits the actual noise characteristics. NLF reveals variation in the standard deviation of noise with respect to image intensity. In contrast to denoising problems, noise in forensic applications is generally weak and content-related, and estimation of noise characteristics must be done in small areas. By exploring the relationship between NLF and the camera response function (CRF), we fit the NLF curve under the CRF constraints. We then formulate a Bayesian maximum a posteriori (MAP) framework to optimize the NLF estimation, and develop a method for image splicing detection according to noise level inconsistency in image blocks taking from different origins. Experimental results are presented to show effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Multiple-Input Multiple-Output (MIMO) techniques are promising in wireless communication systems for its high spectral efficiency. Sphere Detector (SD) is favoured in MIMO detection to achieve Maximum-Likelihood (ML) performance. In this paper, we proposed a new SD method for MIMO-Orthogonal Frequency Division Multiplexing (OFDM) systems based on IEEE802.11n, which uses Singular Value Decomposition (SVD) in complex domain to reduce the computation complexity. Furthermore, a new Schnorr-Euchner (SE) enumeration algorithm is also discussed in detail. The computer simulation result shows that the computational complexity and the number of visited nodes can be reduced significantly compared with conventional SD detectors with the same Bit Error Rate (BER) performance. [ABSTRACT FROM AUTHOR]

Pneumatosis intestinalis (PI) is an uncommon but important condition in which gas is found in a linear or cystic form in the submucosa or subserosa of the bowel wall. PI is a sign, not a disease; therefore, its relevance should be interpreted within the whole clinical context. PI has been found in several distinctive clinical settings: 1) in premature infants with necrotizing enterocolitis; 2) in adults with obstructive pulmonary disease; 3) in adults and children with a wide variety of associated conditions, including pyloric stenosis, jejunoileal bypass, progressive systemic sclerosis, transplantation, ischemic bowel, and drug therapy, particularly steroids, chemotherapy, and immunosuppression; 4) in adults as a primary benign problem; and 5) as an incidental finding in endoscopic mucosal biopsies. The two most important tasks of the physician include: 1) recognition of the entity of PI so that patients are not misdiagnosed and mismanaged as having malignancy or polyposis; and 2) differentiation of the benign variety, in which no intervention is indicated, from the life-threatening form, in which immediate surgery is necessary. Once life-threatening illnesses such as bowel necrosis, perforation, and infections are excluded, patients symptomatic from the cysts per se may be treated with oxygen and/or antibiotics. Because the reports of treatment of PI are at best anecdotal, the decision to treat and the treatment chosen should be carefully balanced with the risks. [ABSTRACT FROM AUTHOR]

The study aimed to determine whether high sensitivity C-reactive protein to prealbumin (hs-CRP/PAB) ratio could be used to predict in-hospital major adverse cardiac events (MACE) in patients with acute coronary syndrome (ACS). A total of 659 patients with ACS were included in the study. Patients were divided into two groups: high hs-CRP/PAB ratio group (hs-CRP/PAB ≥0.010) and low hs-CRP/PAB ratio group (hs-CRP/PAB <0.010). MACE was defined as death, cardiogenic shock, re-infarction and acute heart failure. Logistic regression was performed and the receiver operating characteristic curve (ROC) was generated to evaluate the correlation of hs-CRP/PAB ratio and MACE in patients with ACS. The occurrence rate of MACE was significantly higher in high hs-CRP/PAB ratio group when compared with that in low hs-CRP/PAB ratio group (P < 0.001). Multivariable analysis determined that hs-CRP/PAB ratio was an independent predictor of MACE (adjusted odds ratio: 1.276, 95% confidence interval: 1.106–1.471, P = 0.001). Moreover, the area under the curve value of hs-CRP/PAB ratio for predicting MACE was higher than hs-CRP and equal to PAB. High hs-CRP/PAB ratio was considered as a prognostic parameter of MACE in ACS patients, with the predictive power equal to PAB but greater than hs-CRP. [ABSTRACT FROM AUTHOR]

The expression J' in pages 4, 6, 9, 12 and 13 of the original publication were incorrectly written as J where the symbol prime (') was missing. Also the expression Pi,j found in page 5 of the original publication was incorrectly written as Pi,j. [ABSTRACT FROM AUTHOR]

This paper proposes an improved method for shiftable position-based dual-image reversible data hiding. During the procedure of embedding data, the total number of shiftable coordinates is set as the parameter to make a trade-off between distortion and embedding rate. First, the optimal parameter is sought and the one-to-one code table is generated according to the expected embedding rate. Then, the message data is embedded into the cover image through a simple and effective code table lookup scheme to generate two visually similar stego images. During the procedure of data extraction, the message can be extracted in a reverse manner. The experimental results demonstrate that the proposed method has higher PSNR (peak signal-to-noise ratio) values than our previous work in the case of high embedding rates. [ABSTRACT FROM AUTHOR]

The transport rate of methane from a nutrient solution to the atmosphere via rice plants was controlled both by the methane concentrationin the nutrient solution and by plant physiology. Measurements on 11rice cultivars indicated that the conductance of the rice plant for methane increased as the plants developed. The conductance varied from 0.3+/-0.2 to 1.2+/-0.7 Mumol min-1 mM-1 plant-1 during the tillering stage, and from 0.6+/-0.3 to 2.5+/-0. 2 Mumol min-1 mM-1 plant-1 during the reproduction stage. Based on measurements of all plants, the conductance positively correlated with parameters of plant size. Conductance correlated best with stem inter-cellar volume at the tillering stage, and with root volume at the reproduction stage. For both stages taken together, the correlation between conductance and root volumewas the most significant. The conductance could be approximated by amultiple linear regression using root volume and the length of root bundle. Higher conductance was found to generally associate with the plants with larger root volume, heavier root fresh weight. [ABSTRACT FROM AUTHOR]