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Microbes play a critical role in regulating the size, composition, and turnover of dissolved organic matter (DOM), which is one of the largest pools of carbon in aquatic ecosystems. Global change may alter DOM-microbe associations with implications for biogeochemical cycles, although disentangling these complex interactions remains a major challenge. Here we develop a framework called Energy-Diversity-Trait integrative Analysis (EDTiA) to examine the associations between DOM and bacteria along temperature and nutrient gradients in a manipulative field experiment on mountainsides in contrasting subarctic and subtropical climates. In both study regions, the chemical composition of DOM correlated with bacterial communities, and was primarily controlled by nutrients and to a lesser degree by temperature. At a molecular-level, DOM-bacteria associations depended strongly on the molecular traits of DOM, with negative associations indicative of decomposition as molecules are more biolabile. Using bipartite networks, we further demonstrated that negative associations were more specialized than positive associations indicative of DOM production. Nutrient enrichment promoted specialization of positive associations, but decreased specialization of negative associations particularly at warmer temperatures in subtropical climate. These global change drivers influenced specialization of negative associations most strongly via molecular traits, while both molecular traits and bacterial diversity similarly affected positive associations. Together, our framework provides a quantitative approach to understand DOM-microbe associations and wider carbon cycling across scales under global change.

Diamines are widely used as building blocks for the chemical synthesis of bio-based polymers such as polyamides, polyimides, and polyurea. However, the detection and quantification of diamines are still being as difficult tasks due to their high toxicity and polarity and other hazardous standards are needed to obtain the calibration curve for the diamine quantification. Hence, we have established a simple method for the analysis of aliphatic diamines using GC–MS based on the linear correlations between carbon number, retention time and response factors of diamines. The aliphatic diamines were derivatized with ethylchloroformate (ECF) by applying total ion current (TIC) and single ion monitoring (SIM) at the m/z of 102. The linear correlation of the aliphatic diamines to the retention time (RT) ( R 2 = 0.9949) and response factor (RF) ( R 2 = 0.9538) was determined by using carbon numbers from C3 to C12, via experimentation. The finding of linear correlations between aliphatic diamines are more advantageous and requires less authentic samples of using or calibrating of each diamine sample of the quantification and identification. The established method was successfully employed on a bacterium Shewanella oneidensis which is known to produce potential precursors of the biopolymer synthesis and assessed by, based on the predicted retention time and response factor of 1,4-diaminobutane for the quantification of secreted putrescine and cadaverine. By applying one or two diamines, the retention time, peak area and response factors can easily be expected depending on the concentration and this approach could be applied for the quantification of aliphatic diamines in various industrial sectors.

Recently, high-efficiency video coding (HEVC) has been developed as a new video coding standard focusing on the coding of ultrahigh definition videos as high-resolution and high-quality videos are getting more popular. However, one of the most important challenges in this new standard is its encoding time complexity. Due to this it is quite difficult to implement the HEVC encoder as a real-time system. In this paper, we have addressed this problem in a new way. Generally, for a natural video sequence good amount of coding blocks are "skip" in nature, which need not be transmitted and can be generated in the decoder side using the reference pictures. In this paper, we propose an early skip detection technique for the HEVC. Our proposed method is based on identifying the motionless and homogeneous regions in a video sequence. Moreover, a novel entropy difference-based calculation is proposed in this paper which can predict the skip coding blocks more accurately in a natural video sequence. The experimental result shows our proposed technique can achieve more than 30 % encoding time reduction than the conventional HEVC encoder with negligible degradation in video quality.

Finite element method (FEM) analysis and experimental studies are undertaken on the design of the fiber volume ratio in silicon carbide (SiC) fiber-reinforced SiC composites under indentation contact stresses. Boron nitride (BN)/Pyrocarbon (PyC) are selected as the coating materials for the SiC fiber. Various SiC matrix/coating/fiber/coating/matrix structures are modeled by introducing a woven fiber layer in the SiC matrix. Especially, this study attempts to find the optimum fiber volume ratio in SiC fiber-reinforced SiC ceramics under Hertzian stress. The analysis is performed by changing the fiber type, fiber volume ratio, coating material, number of coating layers, and stacking sequence of the coating layers. The variation in the stress for composites in relation to the fiber volume ratio in the contact axial or radial direction is also analyzed. The same structures are fabricated experimentally by a hot process, and the mechanical behaviors regarding the load–displacement are evaluated using the Hertzian indentation method. Various SiC matrix/coating/fiber/coating/matrix structures are fabricated, and mechanical characterization is performed by changing the coating layer, according to the introduction (or omission) of the coating layer, and the number of woven fiber mats. The results show that the damage mode changes from Hertzian stress to flexural stress as the fiber volume ratio increases in composites because of the decreased matrix volume fraction, which intensifies the radial crack damage. The result significantly indicates that the optimum fiber volume ratio in SiC fiber-reinforced SiC ceramics should be designed for inhibiting the flexural stress.

Curved structural members are widely seen in our surroundings, such as railway supports in playgrounds resembling a c-ring structure. The common geometry of the curved member consists of a segment of a circular ring with a uniform width. The curved section is of constant width in most cardiovascular stents. This study focuses on curved strut members whose width changes along the curved segment. The location of the maximum equivalent stress varies depending on the manner in which the width changes. When the width is constant or larger toward the top, the maximum equivalent stress is developed at the top. Meanwhile, when the area is reduced toward the bottom, the largest equivalent stress is developed some distance from the top. Simple equations, based on the mechanics of materials and the theory of elasticity, were compared favorably with the results from finite element analysis. Included are elaborations of the distribution of the change of stress. The suggested strategy of changing the width, with refinements, could be applied to the optimal design of structural members, including pipes and medical devices such as stents.

N-glycan structures released from miniature pig endothelial and islet cells were determined by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF), negative ion electrospray ionization (ESI) MS/MS and normal-phase high performance liquid chromatography (NP-HPLC) combined with exoglycosidase digestion. Totally, the identified structures were 181 N-glycans including 129 sialylated and 18 α-galactosylated glycans from pig endothelial cells and 80 N-glycans including 41 sialylated and one α-galactosylated glycans from pig islet cells. The quantity of the α-galactosylated glycans from pig islet cells was certainly neglectable compared to pig endothelial cells. A number of NeuGc-terminated N-glycans (80 from pig endothelial cells and 13 from pig islet cells) are newly detected by our mass spectrometric strategies. The detailed structural information will be a matter of great interest in organ or cell xenotransplantation using α 1,3-galactosyltransferase gene-knockout (GalT-KO) pig. Copyright © 2009 John Wiley & Sons, Ltd.

The present research attempts to analyze and evaluate the mechanical behavior of SiCf in SiCf/SiC composites with and without soft coatings. The effects of soft fiber coating in the alleviation of indentation or flexural stress in the layered structure are investigated. Boron nitride and/or pyrocarbon as soft coating layer on SiC fiber are selected for the structure. Modeling is performed by changing the type of fiber, the type of soft layer, and layered stacking sequence of the soft layer. Finite element method (FEM) analyses are conducted to evaluate stress distributions under indentation or flexure loadings by displacement loading. Experimentally, the fiber coatings are conducted in the SiC fiber reinforced SiC composites. It was found that BN and/or pyrocarbon coating on the fiber alleviate the stress under the contact or flexure loading, which indicates that the appropriate design by soft layer on the fiber can reduce the maximum stress.

Video data for the Internet traffic is increasing, and video data transmission is important for consideration of real-time process in the Internet of Things (IoT). Thus, in the IoT environment, video applications will be valuable approach in networks of smart sensor devices. High Efficiency Video Coding (HEVC) has been developed by the Joint Collaborative Team on Video Coding (JCT-VC) as a new generation video coding standard. Recently, HEVC includes range extensions (RExt), scalable coding extensions, and multiview extensions. HEVC RExt provides high resolution video with a high bit-depth and an abundance of color formats. In this paper, a fast intraprediction unit decision method is proposed to reduce the computational complexity of the HEVC RExt encoder. To design intramode decision algorithm, Local Binary Pattern (LBP) of the current prediction unit is used as texture feature. Experimental results show that the encoding complexity can be reduced by up to 12.35% on average in the AI-Main profile configuration with only a small bit-rate increment and a PSNR decrement, compared with HEVC test model (HM) 12.0-RExt4.0 reference software.

Motion estimation part in video compression has high computational complexity. Still a lot of researches for fast scheme are in progress. In this paper, we propose an efficient motion search method based on content-awareness. The proposed method consists of three steps. The first thing is the motion classification for using the center position distribution. The second step is the calculation of predictors according to motion classification. The last is to set the search pattern size by using between predictor and center position distance, adaptively. Due to not utilization of temporal-spatial information, the proposed algorithm can reduce the required memory requirement. Experimental results show that the proposed algorithm can achieve speed-up factor of up to 30.66% on average with quite good bit rate performance, comparing to UMHexagonS and full search method and based on the H.264/AVC reference software (JM).

Objective Lipoteichoic acid (LTA) is an immune-stimulatory component found in the cell wall of lactic acid bacteria, which are a major group of Gram-positive bacteria known to have beneficial health effects in humans. In this study, we evaluated the stimulatory effects of LTAs isolated from different lactobacilli species with mouse macrophage RAW 264.7 cells. Methods RAW 264.7 cells were stimulated with pLTA (isolated from Lactobacillus plantarum K8), rLTA (isolated from Lactobacillus rhamnosus ), dLTA (isolated from Lactobacillus delbreukii ), and sLTA (isolated from Lactobacillus sakei K101). Tumor necrosis factor (TNF)-α and interleukin (IL)-10 production were examined by ELISA, and nitric oxide (NO) production was assayed using Griess reaction. The mRNA and protein expression levels of inducible nitric oxide synthase (iNOS) was examined by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting. Signaling molecules were also examined by Western blotting. Results pLTA and rLTA moderately induced TNF-α, IL-10, and NO production compared with stimulation of RAW 264.7 cells with dLTA and sLTA. Similar results were obtained for the mRNA and protein expression levels of iNOS. Western blot analysis showed that treatment of cells with pLTA or rLTA resulted in minimal phosphorylation of ERK, JNK and p38 MAPK while, dLTA and sLTA were strong activators of MAPK signaling. In addition, the glycolipid structure of LTAs was found to be composed of different fatty acid chain groups and lengths. Taken together, these results suggest that the differential immuno-stimulatory effects of LTAs isolated from different lactobacillus species may be related to their different ability to activate the MAPK signaling pathway, which are modulated by a unique glycolipid structure of LTA.

Various applications based on IoT real-time multimedia are under the spotlight. To implement real-time multimedia service, motion estimation in video compression service has a high computational complexity. In this paper, an efficient motion search method based on content awareness is proposed consisting of three steps. The first step is motion classification using the center position cost distribution. The second step is calculation of a predictor based motion classification. The third step is setting the arm size of the search pattern based on adaptive use of the distance between the predictor and the center position. Experimental results show that the proposed algorithm achieves speed-up factors of up to 48.57% and 16.03%, on average, with good bitrate performance, compared with fast integer-pel and fractional-pel motion estimation for H.264/AVC (UMHexagonS), and an enhanced predictive zonal search for single and multiple frame motion estimation (EPZS) methods using JM 18.5, respectively. In addition, the proposed algorithm achieves a speed-up factor of up to 42.61%, on average, with negligible bitrate degradation, compared with the TZ search motion estimation algorithm for the multiview video coding (TZS) method on HM 10.0.

Benign pulmonary tumors are rare entities, and among them bronchial lipomas are the most uncommon. Up to date, about 80 cases have been reported in the English literature. But, the bronchial lipoma with extrabronchial growth causing middle lobe syndrome and pneumonia is extremely rare. Bronchial lipomas, mainly arising from normal fatty tissue of the proximal portion of the lobar or segmental bronchi, are histologically benign. But if diagnosis and treatments are delayed, they can produce extensive pulmonary parenchymal damage and irreversible brochiectasis distally. So whenever possible, the treatment of choice is resection by means of bronchoscopy via early diagnosis. But if endoscopic removal is not possible because the distal end of the tumor could not be visualized by fiberoptic bronchoscopy or if the nature of the tumor is unclear, surgery is necessary, with lobectomy or pneumonectomy being required in most cases due to the extensively damaged pulmonary parenchyma. We present a case of bronchial lipoma with extrabronchial growth, with a review of the literature and report of an unusual case.