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Machine vision technique is gaining popularity in metal scraps recycling process due to the increasing need for automation and the relatively low cost of industrial camera. Relative movement between camera and scraps within camera exposure time will inevitably cause image motion blur and influence the separation accuracy. In this study, a novel deblurring prior for camera-conveyor system was proposed and applied to a metal separation system. Key performance indicators, like trajectory stability, separation distance, and separation accuracy, were analyzed and compared between blurred-case separation and deblurred-case separation. The results indicated that by applying the proposed deblurring algorithm, the Peak Signal-to-Noise Ratio (PSNR) value of all the blurred images increased, the average PSNR value of all the 31 blurred images is 27.71 and that of the deblurred images is 29.51. Objects center coordinates shift shows a significant decrease after the deblurring process. A higher conveyor speed may increase the separation efficiency, but will cause the decrease of separation accuracy and separation purity. The scraps motion trajectory obtained from deblurred cases is much more stable, which implies a stable landing point of scraps, and by applying the proposed deblurring algorithm, the separation accuracy increases from 82.9 to 88.0%, and separation purity increases from 90.7 to 93.6%. [ABSTRACT FROM AUTHOR]

Recent image captioning models have demonstrated remarkable performance in capturing substantial global semantic information in coarse-grained images and achieving high object coverage rates in generated captions. When applied to fine-grained images that contain heterogeneous object attributes, these models often struggle to maintain the desired granularity due to inadequate attention to local content. This paper investigates a solution for fine-grained caption generation on person-based images and heuristically proposes the Advanced Spectrum Parsing (ASP) model. Specifically, we design a novel spectrum branch to unveil the potential contour features of detected objects in the spectrum domain. We also preserve the spatial feature branch employed in existing methods, and leverage a multi-level feature extraction module to extract both spatial and spectrum features. Further more, we optimize these features, aiming to learn the spatial-spectrum correlation and complete the feature concatenation procedure via a multi-scale feature fusion module. In the inference stage, the integrated features enable the model to focus more on the local semantic regions of the person in the image. Extensive experimental results demonstrate that the proposed ASP for person-based datasets can yield promising results with both comprehensiveness and fine graininess. [ABSTRACT FROM AUTHOR]

As one of the most significant contaminants and stressors in aquaculture systems, ammonia adversely jeopardizes the health of aquatic animals. Ammonia exposure affects the development, metabolism, and survival of shellfish. However, the responses of the innate immune and antioxidant systems and apoptosis in shellfish under ammonia stress have rarely been reported. In this study, razor clams (Sinonovacula constricta) were exposed to different concentrations of non-ion ammonia (0.25 mg/L, 2.5 mg/L) for 72 h and then placed in ammonia-free seawater for 72 h for recovery. The immune responses induced by ammonia stress on razor clams were investigated by antioxidant enzyme activities and degree of apoptosis in digestive gland and gill tissues at different time points. The results showed that exposure to a high concentration of ammonia greatly disrupted the antioxidant system of the razor clam by exacerbating the accumulation of reactive oxygen species ( O 2 - , H2O2) and disordering the activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), and the level of activity remained at a significantly high level after recovering for 72 h (P < 0.05). In addition, there were significant differences (P < 0.05) in the expression of key genes (Caspase 7, Cyt-c, Bcl-2, and Bax) in the mitochondrial apoptotic pathway in the digestive glands and gills of razor clams as a result of ammonia stress and were unable to return to normal levels after 72 h of recovery. TUNEL staining indicated that apoptosis was more pronounced in gills, showing a dose and time-dependent pattern. As to the results, ammonia exposure leads to the activation of innate immunity in razor clams, disrupts the antioxidant system, and activates the mitochondrial pathway of apoptosis. This is important for comprehending the mechanism underlying the aquatic toxicity resulting from ammonia in shellfish. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the relationship between lens morphology and aberrations in patients with myopia. Methods: This cross-sectional study included 155 patients with myopia in their right eyes. Spherical power and cylindrical power were achieved by cycloplegic autorefraction. The eyes were divided into three groups for analysis based on their spherical equivalent (SE) values. The 4 mm and 6 mm ocular and internal aberrations were measured using the OPD-scan III. Lens parameters were measured using CASIA2, including lens thickness (LT), radius of anterior/posterior lens surface curvature (RAL/RPL), lens decentration (DEC), and lens tilt (TILT). The differences of lenticular parameters and aberration parameters among the three groups analyzed with ANOVA or Kruskal Wallis test. Pearson correlation or Spearman correlation analysis was performed to evaluate the relationships between the lens parameters and aberrations. A p value < 0.05 indicated statistical significance. Results: The difference in LT, RAL, DEC and TITL among the three groups was statistically significant (p < 0.05). And there were differences among differences in internal high-order aberrations, spherical aberration, and coma aberration(p < 0.05).Spherical power was positively correlated with LT and TITL (p < 0.05) and negatively correlated with DEC, RAL, and RPL (p < 0.05). Cylindrical power was positively correlated with LT (p < 0.05) and negatively correlated DEC (p < 0.05); The lenticular parameters (LT, RAL, DEC, and TILT) were mainly correlated with the ocular and internal spherical aberration. LT and DEC were correlated with ocular and internal higher-order aberrations and coma aberration. Conclusion: DEC and LT were the main factors affecting aberrations in patients with myopia. [ABSTRACT FROM AUTHOR]

The age and parity of female primates could reflect their physical condition and reproductive experience. Consequently, the individual age-parity dependent condition of mothers and the survival of their offspring represents a fitness tradeoff. This reproductive tradeoff is expressed in the individual birth sex ratio, offspring mortality and interbirth interval (IBI). Maternal antenatal and postnatal investment hypotheses predict that more female offspring are produced by experienced mothers in poor condition (Trivers-Willard hypothesis), and that offspring mortality decreases and IBI shortens with parity (targeted reproductive effort hypothesis). Here we test the latter predictions in captive populations of the endangered Francois' langur (Trachypithecus francoisi), using long-term demographic and reproductive data from 21 Chinese zoos and three breeding centers. In these captive populations, birth sex ratio changed slightly from male-biased to female-biased as parity increased above five offspring in experienced mothers, consistent with the Trivers-Willard hypothesis. Although mortality of male offspring was greater than female offspring, overall offspring mortality did not vary with maternal parity. There was no significant difference in duration of postnatal care or IBI between male and female offspring. However, IBI for both female and male offspring shortened overall with increasing parity, as predicted by the targeted reproductive effort hypothesis. Females with more reproductive experience that produce more female offspring are critical to captive breeding programs that aim to increase the overall viable population size of this endangered species. Significance statement: For primates with a slow life-history, it is important to understand how mothers age and parity affects their reproductive fitness. We investigated maternal investment strategies of captive Francois' langurs, specifically the effect of age and parity on the birth sex ratio, offspring mortality and interbirth interval. Mothers relied more on parity (i.e., their experience) to adjust the birth sex ratio, and had more sons in the first few parities. Mothers also spent significantly less time taking care of offspring as their reproductive experience increased and physical condition was likely declining. Thus, Francois' langurs are able to adjust their investment in reproduction as they become more experienced (greater parity) to optimize reproductive fitness. [ABSTRACT FROM AUTHOR]

Ferroelectric ceramic capacitors show great potential in pulse power devices for their fast charging-discharging characteristics and immense power density. As a relaxation ferroelectric material, Sr0.7Bi0.2TiO3 has the advantage of high energy storage efficiency. Nevertheless, its low breakdown strength limits its energy storage performance. Herein, Sr0.7Bi0.2Ti(1–1.25x)TaxO3 (SBT-T) ceramics were synthesized by introducing Ta2O5 with a broad bandgap. On the one hand, the B-site ion disorder enhanced the relaxor behavior of the SBT-T ceramics. On the other hand, the introduction of Ta boosted the impedance and activation energy of the SBT-T ceramics, thus significantly improving their breakdown strength. With the increase in Ta content, the critical electric fields of SBT-T ceramics were monotonically increased from 240 to 370 kV/cm (increased by 54%), and splendid Wrec = 2.33 J/cm3 and high η = 91.76% were achieved when x = 0.04 under 290 kV/cm. Additionally, the SBT-0.04T ceramics demonstrated excellent pulse charge–discharge speed (t0.9 of 81.69 ns) and power density (PD of 153.39 MW/cm3). This research revealed that Ta doping was an effective approach to strengthening breakdown strength, which might provide ideas for improving the energy storage performance of dielectric capacitors. [ABSTRACT FROM AUTHOR]

There has been considerable interest in transforming peptides into small molecules as peptide-based molecules often present poorer bioavailability and lower metabolic stability. Our studies looked into building machine learning (ML) models to investigate if ML is able to identify the 'bioactive' features of peptides and use the features to accurately discriminate between binding and non-binding small molecules. The ghrelin receptor (GR), a receptor that is implicated in various diseases, was used as an example to demonstrate whether ML models derived from a peptide library can be used to predict small molecule binders. ML models based on three different algorithms, namely random forest, support vector machine, and extreme gradient boosting, were built based on a carefully curated dataset of peptide/peptidomimetic and small molecule GR ligands. The results indicated that ML models trained with a dataset exclusively composed of peptides/peptidomimetics provide limited predictive power for small molecules, but that ML models trained with a diverse dataset composed of an array of both peptides/peptidomimetics and small molecules displayed exceptional results in terms of accuracy and false rates. The diversified models can accurately differentiate the binding small molecules from non-binding small molecules using an external validation set with new small molecules that we synthesized previously. Structural features that are the most critical contributors to binding activity were extracted and are remarkably consistent with the crystallography and mutagenesis studies. [ABSTRACT FROM AUTHOR]

Purpose: To compare the diagnostic value of ultrasonic elastosonography (UE) and contrast-enhanced ultrasonography (CEUS) for benign and malignant intraocular tumors. Methods: This retrospective study enrolled patients with intraocular tumors at Beijing Tongren Hospital, Capital Medical University (August 2016 to January 2020). The strain rate ratio (strain rate of tumor tissue divided by strain rate of surrounding normal tissue) was measured by UE. CEUS was performed using SonoVue® contrast agent. The performance of each method at differentiating benign from malignant intraocular tumors was evaluated by receiver operating characteristic curve analysis. Results: The analysis included 147 eyes in 145 patients (45.6 ± 13.4 years-old; 66 males): 117 patients (119 eyes) with malignant tumors and 28 patients (28 eyes) with benign tumors. At an optimal cutoff of 22.67 for the strain rate ratio, UE distinguished benign from malignant tumors with a sensitivity of 86.6% and a specificity of 96.4%. CEUS showed that 117 eyes with malignant tumors had a fast-in, fast-out time-intensity curve, and only two eyes with malignant tumors had a fast-in, slow-out curve, while all 28 eyes with benign tumors had a fast-in, slow-out curve. CEUS differentiated benign from malignant tumors with a sensitivity of 98.3% and a specificity of 100%. The diagnostic results differed significantly between the two methods (P = 0.004, McNemar test). The diagnostic performances of the two tests were moderately consistent (κ = 0.657, P < 0.001). Conclusion: Both CEUS and UE have good diagnostic value in the differentiation of benign intraocular tumors from malignant intraocular tumors. [ABSTRACT FROM AUTHOR]

Realization problems, including the minimum realization of Boolean control networks (BCNs), are investigated by the vertex partition method. A general definition of the realization for BCNs that does not involve any subspaces is proposed. For the new and existing realization definitions, by a common concolorous perfect vertex partition (CCP-VP) of vertex-colored state transition graphs, an equivalence relation and a quotient mapping are defined, which induce a quotient system, i.e., the realization of original BCNs. In addition, if the CCP-VP is an equal partition, a realization induced by a γ-friendly controlled invariant regular subspace is constructed. Finally, an algorithm is designed to construct the minimum realization of BCNs for different realization definitions, and three examples are given to illustrate the obtained results. [ABSTRACT FROM AUTHOR]

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Surface contact fatigue is one of the main failure modes of precision bearing, which can result in performance degradation, such as increased vibration or abnormal sound. By comparatively analyzing the damage characteristics of two types of failure bearings, hybrid ceramic ball bearing and steel ball bearing operating under real working conditions, the differences of the surface fatigue mechanisms are clarified. For hybrid ceramic ball bearing, the Si-contained hard particles detached from the surface of ceramic balls are squeezed into the surface of raceway, which leads to the micropits and surface cracks. For steel ball bearing, the cracks can initiate on the surface wrinkle regions (SWRs). The cracks originated from the cavities and microcracks can also form in the surface plastic deformation layer in the two types of bearings. The formation mechanisms of cracks on the surface and in the plastic deformation layer present synergistic effect, which results in the peeling band on the raceways together. From the damage characteristics of the two bearings in this study, it can be seen that the surface technology application might mitigate the surface fatigue in steel ball bearing application. Also, it is necessary to solve the problem of the peeling in ceramic balls to improve performance of anti-surface fatigue of hybrid ceramic ball bearings. [ABSTRACT FROM AUTHOR]

Environmental pollution caused by potentially toxic elements (PTEs) has become a global problem that endangers environmental sustainability due to industrial, agricultural, and urban pollution. Primula forbesii Franch. (a synonym of Primula filipes G. Watt.) is a biennial flower native to China with excellent stress resistance and ornamental value. In this study, we examined the phenotypic traits, growth indexes, and physiological properties of P. forbesii in response to five representative PTEs (Cd, Ni, Cr(III), Cu, and Zn) under hydroponic culture conditions. High concentrations of Zn and Cr had little effect on the growth and physiological properties of P. forbesii, indicating that the species has strong tolerance to Zn and Cr stress. Alternatively, high concentrations of Cd, Ni, and Cu seriously affected plant growth and development, resulting in leaf chlorosis and even death, and therefore may have a serious negative impact on the growth of P. forbesii. However, activity levels of some antioxidant enzymes and osmotic regulatory substances remained high, indicating that P. forbesii resisted PTE stress by regulating physiological and biochemical metabolism to a certain extent. Furthermore, principal component analysis and membership function were used to comprehensively evaluate P. forbesii resistance to PTEs. These analyses revealed that P. forbesii exhibits distinct sensitivities and physiological responses to different PTEs and suggested that the resistance to five PTEs in decreasing order is Zn > Cr > Cd > Cu > Ni. These results provide a theoretical basis for the future application of P. forbesii in environments with PTE pollution and may expand its practical utilization. [ABSTRACT FROM AUTHOR]

In this paper, two block-decoupling problems of Boolean control networks (BCNs), one of which is related to system decomposition and the other is not, are investigated by using the method of the semi-tensor product of matrices. Necessary and sufficient graphic conditions for block-decoupling of BCNs in the two cases are obtained. Moreover, a logical coordinate transformation is constructed to achieve block-decoupling related to system decomposition when the corresponding graphic conditions are satisfied. Finally, two illustrative examples are provided to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

Industrial robots are increasingly applied in the automatic die repair welding via the prevalent wire and arc additive manufacturing (WAAM) technology. However, the precise calibration of work coordinates is indispensable for the off-line programming of robotic welding paths, which often results in positioning error, path deviation, or even tool collisions. The die is pre-heated at about 500 °C before the robotic WAAM processes. Thus, it is challenging to calibrate work coordinates by touch sensing because those points on the X-axis and the Y-axis to determine the location of the part need to be caught by human eyes. In this paper, a camera vision calibration (CVC) method based on stereo vision is developed. Image feature points are extracted by a multi-saliency fusion algorithm based on the human visual attention mechanism. Through stereo vision, 3D information of the feature points is obtained, and the workpiece coordinate system (WCS) is finely calibrated. Compared with the random error of human vision calibration (HVC), the proposed method could improve the workpiece's calibration accuracy, reduce the unexpected collisions in limited space, and improve the dimensional precision of the welding layer. [ABSTRACT FROM AUTHOR]

In robotic GMAW-based additive manufacturing, the surface evenness of the deposited layer was significant to the dimensional accuracy and the stable fabrication process, and it was determined by the multi-bead overlapping distance. To obtain the optimal overlapping distance, a group of two-bead overlapping experiments was conducted with different overlapping ratio. The cross-section shape was observed and the variation of the bead profile caused by the damming up of the previous bead was investigated. The second bead profile could be fitted by a rotated varying parabola or circular arc function with the decreasing of the overlapping distance from the initial single bead width (w) to 0. A varying cross-section profile overlapping model was developed based on the actual forming characteristics of the overlapping experiment, through which the varying profile of two overlapping beads with arbitrary distance could be predicted. Then, the optimal overlapping distance was calculated under some principles to achieve a relatively flat top surface and stable overlapping process, and the multi-bead overlapping experiments were performed to validate the model. The results showed that the model could achieve an excellent approximation to the actual overlapping experiment, and the good surface evenness and stable overlapping process was obtained, which was significant to the research into the appearance optimization in GMAW-based additive manufacturing. [ABSTRACT FROM AUTHOR]

In wire and arc additive manufacturing, the weld bead geometry determined the slicing layer height, which was decided by the welding parameters. Generally, the determination of the welding parameters relied on empirical and experimental data through the trial-and-error methods that incur considerable time and cost. To obtain the proper welding process parameters according to the desired single bead geometry and layer height, a full factorial experimental design matrix was applied to collect the original data of welding parameters and bead geometrical variables. A forward artificial neural network (FANN) was built to predict the bead geometry form the welding parameters. Then, a closed-loop iteration method combined a genetic algorithm (GA) and the FANN model (FANN-GA) was developed to search for the most optimal welding process parameters in accordance with the selected bead geometrical variables. The results confirmed that the FANN-GA model has a good performance on the backward prediction of the welding process parameters compared with the direct backward artificial neural network (BANN). Several groups of single layer multi-bead and multi-layer multi-bead experiment were performed to testify the proposed method, and the relative error between the desired and actual layer height was small. The proposed method makes it possible to fabricate the component with an arbitrary desired layer height, and could be used in the adaptive slicing additive manufacturing or surface coating. [ABSTRACT FROM AUTHOR]

Genomic studies have established a set of three core-signaling pathways, receptor tyrosine kinase (RTK), p53 and retinoblastoma (Rb) signaling pathways, contributing glioblastoma (GBM) and revealed that dysregulation of at least two pathways is required for GBM progression. In the present study, we investigate efficacy of combination of palbociclib, cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, and erlotinib, epidermal growth factor receptor (EGFR) inhibitor in GBM cell systems with different p53 status. Cell proliferation and colony formation assays showed that the combination treatment synergistically suppressed GBM cell proliferation. LN229 cells with mutant p53 and wild-type PTEN were more sensitive to the combination treatment. Further studies indicated that the synergetic anti-GBM effects were due to cell apoptosis induction and cell cycle arrest at G1 phase. Signaling examination indicated that levels of p-Rb and p-4E-BP1 significantly decreased by the combination treatment; however, Akt and MAPK signaling were differentially suppressed among the three GBM cell lines. Hence, our data demonstrate that palbociclib and erlotinib exert synergistic anti-GBM activity, providing pre-clinical evidence and a proof-ofconcept that usage of the combination of EGFR and CDK4/6 inhibitors for GBM treatment. [ABSTRACT FROM AUTHOR]

Fertilizer regime is playing an important role in heavy metal cadmium (Cd) accumulation in paddy soils and crop plant. It is necessary to assess the Cd accumulation in soils and rice (Oryza sativa L.) plants under long-term fertilization managements, and the results which help to assess the environmental and food risk in Southern China. However, the effects of different organic manure and chemical fertilizers on Cd accumulation in soils and rice plant remain unclear under intensively cultivated rice conditions. Therefore, the objective was to explore Cd accumulation in paddy soils and rice plant at mature stage under different long-term fertilization managements in the double-cropping rice system. Cd accumulation in the surface soils (0-20 cm) and rice plant with chemical fertilizer alone (MF), rice straw residue and chemical fertilizer (RF), 30% organic matter and 70% chemical fertilizer (LOM), 60% organic matter and 40% chemical fertilizer (HOM), and without fertilizer input (CK) basis on 32 years long-term fertilization experiment were analyzed. The results showed that the soil total Cd content was increased by 0.296 and 0.351 mg kg−1 and 0.261 and 0.340 mg kg−1 under LOM and HOM treatments at early and late rice mature stages, respectively, compared with the CK treatment. And the soil available Cd content was increased by 0.073 and 0.137 mg kg−1 and 0.102 and 0.160 mg kg−1 under LOM and HOM treatments at early and late rice mature stages, respectively, compared with the CK treatment. The bioconcentration factor of Cd across different parts of rice plant was the highest in root, followed by stem and grain, and the lowest in leaves. At early and late rice mature stages, the root Cd concentration of rice plant was increased by 0.689 and 0.608 mg kg−1 with HOM treatment, the stem Cd concentration of rice plant was increased by 0.666 and 0.758 mg kg−1 with RF treatment, and the leaf and grain Cd concentration of rice plant was increased 0.094 and 0.082 mg kg−1 and 0.086 and 0.083 mg kg−1 with LOM treatment, respectively, compared with the CK treatment. The soil Cd single-factor contaminant index (PCd) under different fertilization treatments was as the following HOM > LOM > RF > MF > CK. Meanwhile, the PCd with LOM and HOM treatments was higher than that of the MF, RF, and CK treatments, but there is no significant difference between that of MF and RF treatments. Therefore, long-term application of rice straw residue and chemical fertilizer had no obvious effect on the accumulation of Cd in paddy soils and grain, and soil Cd accumulation was increased as application of organic fertilizer. [ABSTRACT FROM AUTHOR]

Dy3+ and Sm3+ activated Ca3Si2O4N2 samples have been prepared by high temperature solid state reaction, and their luminescence properties were investigated. The excitation spectrum of Ca3Si2O4N2:0.02Dy3+ monitored at 576 nm has several strong peaks from 340 to 410 nm. Under 365 nm excitation, its emission spectrum exhibits a dominant peak located at about 576 nm with the Commission Internationale de l’Eclairage chromaticity coordinates of (0.395, 0.422) and the correlated color temperature of 3932 K. Sm3+ doped Ca3Si2O4N2 exhibits red emission originating from 4G5/2 to 6HJ (J = 5/2, 7/2, 9/2 and 11/2) transitions, and the charge transfer band of Sm3+ was observed at an unusually low energy of 4.29 eV. As the concentration of Sm3+ increases, the emission intensity of the electric-dipole transition becomes stronger than that of the magnetic-dipole transition, indicating that the local environment of Sm3+ ions becomes more asymmetric. With the increasing temperature, both Sm3+ and Dy3+ doped Ca3Si2O4N2 phosphors exhibit satisfactory thermal stabilities. [ABSTRACT FROM AUTHOR]

Split-inteins are a subset of inteins that are expressed in two separate halves and catalyze splicing in trans upon association of the two domains. They occur naturally and have also been artificially generated by splitting of contiguous ones. With their unique properties, split-inteins offer improved controllability, flexibility and capability to existing tools based on contiguous inteins. In addition, split-inteins have proven useful in several new applications. This review gives a general introduction to split-inteins with a focus on their role in expanding the applications of intein-based technologies. [ABSTRACT FROM AUTHOR]

Background and aim: Tobacco-rice rotation is a useful traditional practice for controlling crop diseases and pests. However, its effect on rice pests has not been studied. We aimed to clarify the ecological effect of tobacco-rice rotation on two destructive rice pests Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth). Methods: Populations of rice planthoppers N. lugens and S. furcifera in rice-rice successive cropping (RRSC) and tobacco-rice rotation cropping (TRRC) paddy fields were counted using large white plates. The nicotine concentration of soils, rice plants (divided into leaves, stems, roots and panicles) collected from TRRC and RRSC fields were quantitatively analyzed using the LC-MS/MS technique. Results: There was a large and significant difference between TRRC and RRSC systems in total number of rice planthoppers. Moreover, the nicotine concentrations of soils and in rice (roots, stems and leaves) in TRRC were significantly higher than those in RRSC, especially in roots the concentration was 1000 times higher, but there was no significant difference in concentration in rice panicles. Conclusion: This study suggests that nicotine uptake by rice roots, from soil containing tobacco residues in the TRRC system, affected the abundances of S. furcifera and N. lugens. [ABSTRACT FROM AUTHOR]

Scygonadin is an antimicrobial protein isolated from the mud crab, Scylla serrate. The mature protein comprises 102 amino acids and has a theoretical molecular weight of 11,272 Da. The protein's specific expression pattern strongly suggests that it plays a role in reproductive immunity. In this study, I developed a protocol for producing recombinant scygonadin in Escherichia coli. The target protein was expressed as both thioredoxin and SUMO fusions, and released by TEV and SUMO protease-mediated cleavages, respectively. In either case, the liberated scygonadin was separated from its carrier using a HisTrap HP column. From thioredoxin and SUMO fusion constructs, 32.7 and 29.2 mg target protein per liter of culture was obtained, respectively. The described protocol provides an effective means for producing scygonadin in relatively large quantities, which facilities its further characterization. [ABSTRACT FROM AUTHOR]

BirA is a biotin ligase from Escherichia coli that specifically biotinylates a lysine side-chain within a 15-amino acid acceptor peptide (also known as Avi-tag). We developed a protocol for producing recombinant BirA ligase in E. coli for in vitro biotinylation (Li and Sousa, Prot Expr Purif, 82:162-167, ) in which the target protein was expressed as both thioredoxin and MBP fusions, and was released by TEV protease-mediated cleavage. The liberated ligase and the fusion proteins were enzymatically active. Based on that observation, we have now developed a novel system for in vivo biotinylation by co-expressing the Avi-tagged target protein with the MBP-BirA fusion. The effectiveness of this system was demonstrated by the successful in vivo labeling of antimicrobial protein, scygonadin. This new system shows improved efficiency compared with pre-existing one and this is likely attributed to the high expression level and solubility of the co-expressed MBP-BirA. [ABSTRACT FROM AUTHOR]

Many aquatic organisms are negatively affected by exposure to high copper concentrations. We investigated the biochemical response of the mussel Mytilus coruscus (Mytiloida: Mytilidae) to copper exposure. In vivo bioassays using M. coruscus and different copper concentrations were conducted. The activity of six biomarkers, namely superoxide dismutase (SOD), catalase (CAT), acid phosphatase (ACP), alkaline phosphatase (AKP), glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) were measured. Survival rates decreased with increased copper concentrations and exposure times. The LC values at 48, 72, and 96 h exposure were 0.48, 0.37, and 0.32 mg/L, respectively. Within digestive glands, CAT activity increased with increasing Cu concentrations. The activity of AKP showed no significant change, while the remaining four enzymes showed decreasing activity with increasing Cu concentrations. Within the gills, AKP activity increased when the Cu concentration was 0.05 mg/L, but showed no significant changes at higher concentrations. Activity of CAT and ACP within gills tended to decrease with increasing Cu concentration. The activity of SOD and GPT decreased at an exposure concentration of 0.2 mg/L. GOT activity within gills decreased at 0.1 mg/L and increased at an exposure concentration of 0.2 mg/L. Within the adductor muscle, AKP activity increased at 0.05 mg/L but did not change at higher exposure concentrations. ACP activity within adductor muscle tissue showed no change, while activities of CAT, GOT and GPT decreased with increasing Cu concentrations. SOD activity within the adductor muscle tissue significantly decreased at the 0.02, 0.05 and 0.2 mg/L exposure concentrations. Our results show tissue specific differences for the six biomarkers in for M. coruscus. Our findings provide the basis for the establishment of reference activity levels against which biomarker changes can be estimated, and are essential preliminary steps in development of in vivo bioassays. [ABSTRACT FROM AUTHOR]

The scattered fields of plane waves in a solid from a cylinder or sphere are critical in determining its acoustic characteristics as well as in engineering applications. This paper investigates the scattered field distributions of different incident waves created by elastic cylinders embedded in an elastic isotropic medium. Scattered waves, including longitudinal and transverse waves both inside and outside the cylinder, are described with specific modalities under an incident plane wave. A model with a scatterer embedded in a structural steel matrix and filled with aluminum is developed for comparison with the theoretical solution. The frequency of the plane wave ranged from 235 kHz to 2348 kHz, which corresponds to scaling factors from 0.5 to 5. Scattered field distributions in matrix materials blocked by an elastic cylindrical solid have been obtained by simulation or calculated using existing parameters. The simulation results are in good agreement with the theoretical solution, which supports the correctness of the simulation analysis. Furthermore, ultrasonic phased arrays are used to study scattered fields by changing the characteristics of the incident wave. On this foundation, a partial preliminary study of the scattered field distribution of double cylinders in a solid has been carried out, and the scattered field distribution at a given distance has been found to exhibit particular behaviors at different moments. Further studies on directivities and scattered fields are expected to improve the quantification of scattered images in isotropic solid materials by the phased array technique. [ABSTRACT FROM AUTHOR]

Biohydrogen technology has drawn much attention due to its many advantages. However, it is still necessary to screen much more strains with stronger hydrogen-producing capacity for future commercialization processes. In this paper, a biohydrogen-producing strain Enterobacter aerogenes EB-06 was isolated, identified, and named. It could convert glycerol to biohydrogen by microorganism fermentation. The effects of oxygen content, initial pH, initial glycerol concentration, and initial nitrogen source content on biohydrogen production process were investigated. The results have shown that biohydrogen generation was more favorable under anaerobic conditions. The optimum specific biohydrogen production rate (QH2) was obtained as 41.47 mmol H2/g DCW h at 40 g/L initial glycerol concentration. The optimum volume H2 yield (CH2) was 83.76 mmol H2/L at initial pH 7.0. It was found that nitrogen source content (0–4 g/L) could promote biohydrogen production and cell growth. The biohydrogen production of Enterobacter aerogenes EB-06 from glycerol was optimized by the orthogonal experimental design. The optimal yield coefficient of biohydrogen from glycerol fermentation (YH2/glycerol) of EB-06 was obtained as 1.07 mmol H2/ mol glycerol at 10 g/L initial glycerol concentration, initial pH 5.0, and initial C/N ratio 5/3. [ABSTRACT FROM AUTHOR]

Sex differences in susceptibility and progression have been reported in numerous diseases. Female cells have two copies of the X chromosome with X-chromosome inactivation imparting mono-allelic gene silencing for dosage compensation. However, a subset of genes, named escapees, escape silencing and are transcribed bi-allelically resulting in sexual dimorphism. Here we conducted in silico analyses of the sexes using human datasets to gain perspectives into such regulation. We identified transcription start sites of escapees (escTSSs) based on higher transcription levels in female cells using FANTOM5 CAGE data. Significant over-representations of YY1 transcription factor binding motif and ChIP-seq peaks around escTSSs highlighted its positive association with escapees. Furthermore, YY1 occupancy is significantly biased towards the inactive X (Xi) at long non-coding RNA loci that are frequent contacts of Xi-specific superloops. Our study suggests a role for YY1 in transcriptional activity on Xi in general through sequence-specific binding, and its involvement at superloop anchors. [ABSTRACT FROM AUTHOR]