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Tight glutenite reservoir structure is complex, mineral types are multi-seepage, and most of them are non-Darcy's law flows Based on the finite element COMSOL simulation of seepage flow in glutenite water flooding, this chapter mainly explores the influence of several related factors on displacement recovery. With the increase of wetting angle, the wettability makes the porous state of solids and fluids in glutenite stable, so that water can easily push oil out, which leads to the increase of water flooding recovery The higher the injection rate, the higher the water cut in a short time, which makes the oil-water two-phase displacement accelerate and the higher the displacement recovery With the increase of gravel diameter, the oil saturation decreases less and more crude oil is bound by the pore structure surrounded by large particles, which is not conducive to displacement Small gravel particles have little influence on the front of water drive, and there is no obvious dominant channel, which leads to the recovery effect. [ABSTRACT FROM AUTHOR]

Titanium alloy plate is widely used in automotive, aerospace, medical and other fields. Ultrasonic testing is a highly efficient non-destructive testing method for the inspection of titanium alloy components. However, there are strong distortion and attenuation of sound wave propagation in titanium alloys due to the presence of anisotropy and inhomogeneities, making it difficult to detect tiny defects in such components. In addition, some configuration parameters, such as the water path depth also affect the distribution of the acoustic field in the detected components. It is necessary to predict the acoustic field distribution to achieve a better testing accuracy. An acoustic field simulation method based on a multi-Gaussian beam is proposed, which can model the focused acoustic field in a multilayer anisotropy medium. The relationship between the acoustic focused area and the water path depth was explored and optimised comprehensively. C-scan imaging of specimen with flat bottom holes was performed at different water path depths. The results show that the proposed method can optimise the configuration parameters to improve the accuracy of the flaw sizing. This study provides an effective method for testing titanium alloy plate. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis is a lethal and progressive pulmonary disorder in human beings. Ephedrine is a compound isolated from Ephedra and plays a regulatory role in inflammatory response. This study focused on the anti-pulmonary fibrosis effect of ephedrine and its potential molecular mechanism. After a mouse model of pulmonary fibrosis was established through bleomycin (BLM) induction, the survival percentage, body weight, and pulmonary index were measured. Hematoxylin-eosin staining and Masson’s trichrome staining for lung tissues were performed to observe the pathological alterations. The viability of lung epithelial BEAS-2B cells, intracellular production of reactive oxygen species, and the levels of pro-inflammatory cytokines were examined by cell counting kit-8 assays, 2ʹ,7ʹdichlorofluorescein diacetate (DCF-DA) staining, and enzyme-linked immunosorbent assay, respectively. Immunofluorescence staining was performed to determine E-cadherin and vimentin expression after BLM or ephedrine treatment. The mRNA and protein levels of cytokeratin-8, E-cadherin, α-SMA, and vimentin were subjected to quantitative polymerase chain reaction and immunoblotting. Experimental results revealed that ephedrine treatment rescued the repressive impact of BLM on BEAS-2B cell viability, and ephedrine inhibited BLM-induced overproduction of reactive oxygen species and inflammatory response in BEAS-2B cells. Additionally, ephedrine suppressed epithelial-mesenchymal transition (EMT) process stimulated by BLM treatment, as demonstrated by the reduced α-SMA and vimentin levels together with the increased cytokeratin-8 and E-cadherin levels in BLM + Ephedrine group. In addition, ephedrine inhibited NF-κB and activated Nrf-2 signaling in BLM-treated BEAS-2B cells. Moreover, ephedrine ameliorated pulmonary fibrosis in BLM-induced mice and improved the survival of model mice. In conclusion, ephedrine attenuates BLM-evoked pulmonary fibrosis by repressing EMT process via blocking NF-κB signaling and activating Nrf-2 signaling, suggesting that ephedrine might become a potential antipulmonary fibrosis agent in the future. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis is a lethal and progressive pulmonary disorder in human beings. Ephedrine is a compound isolated from Ephedra and plays a regulatory role in inflammatory response. This study focused on the anti-pulmonary fibrosis effect of ephedrine and its potential molecular mechanism. After a mouse model of pulmonary fibrosis was established through bleomycin (BLM) induction, the survival percentage, body weight, and pulmonary index were measured. Hematoxylin-eosin staining and Masson's trichrome staining for lung tissues were performed to observe the pathological alterations. The viability of lung epithelial BEAS-2B cells, intracellular production of reactive oxygen species, and the levels of pro-inflammatory cytokines were examined by cell counting kit-8 assays, 2',7'- dichlorofluorescein diacetate (DCF-DA) staining, and enzyme-linked immunosorbent assay, respectively. Immunofluorescence staining was performed to determine E-cadherin and vimentin expression after BLM or ephedrine treatment. The mRNA and protein levels of cytokeratin-8, E-cadherin, a-SMA, and vimentin were subjected to quantitative polymerase chain reaction and immunoblotting. Experimental results revealed that ephedrine treatment rescued the repressive impact of BLM on BEAS-2B cell viability, and ephedrine inhibited BLM-induced overproduction of reactive oxygen species and inflammatory response in BEAS-2B cells. Additionally, ephedrine suppressed epithelial-mesenchymal transition (EMT) process stimulated by BLM treatment, as demonstrated by the reduced a-SMA and vimentin levels together with the increased cytokeratin-8 and E-cadherin levels in BLM + Ephedrine group. In addition, ephedrine inhibited NF-kB and activated Nrf-2 signaling in BLM-treated BEAS-2B cells. Moreover, ephedrine ameliorated pulmonary fibrosis in BLM-induced mice and improved the survival of model mice. In conclusion, ephedrine attenuates BLM-evoked pulmonary fibrosis by repressing EMT process via blocking NF-kB signaling and activating Nrf-2 signaling, suggesting that ephedrine might become a potential antipulmonary fibrosis agent in the future. [ABSTRACT FROM AUTHOR]

Infrared imaging is widely used due to its penetration capability to operate under many weather or lighting condition. However, due to the far distance of aerial view, feature blur, and the scarcity of aerial infrared data, the detection of small infrared targets on the water surface remains a challenging problem. In response to the problem of unclear features, we propose the spatial feature weighting method based on 2D Gaussian distribution. This method increases the weight of the target area by adaptively adjusting the feature activation. Secondly, for the problem of rare aerial perspective infrared data, we propose the cross‐spectral data migration method. By introducing the domain difference loss function to optimize the pseudo‐label selection process, the range of target domain distribution is expanded, and the adaptability of the detector is improved. Finally, in response to the problem of underfitting caused by category imbalance in transfer learning, we propose the class balancing method that effectively reduces the false detection. Extensive experiments were conducted on both benchmark datasets and the self‐built dataset to evaluate the effectiveness and robustness of our method. The proposed method was evaluated with different models and various scenarios, and the results demonstrated the effectiveness. [ABSTRACT FROM AUTHOR]

Background: Clinical competency is the ability to integrate knowledge, skills, attitudes and values into a clinical situation and it is very important in nursing education, clinical settings, nursing management, and crises. This study aimed to investigate nurses' professional competence and its correlates before and during the COVID-19 pandemic. Methods: We conducted this cross-sectional study before and during the COVID-19 outbreak and recruited all nurses working in hospitals affiliated to Rafsanjan University of Medical Sciences, southern Iran, so we included 260 and 246 nurses in the study before and during the COVID-19 epidemic, respectively. Competency Inventory for Registered Nurses (CIRN) was used to collect data. After inputting the data into SPSS24, we analysed them using descriptive statistics, chi-square and multivariate logistic tests. A significant level of 0.05 was considered. Results: The mean clinical competency scores of nurses were 156.97 ± 31.40 and 161.97 ± 31.36 before and during the COVID-19 epidemic, respectively. The total clinical competency score before the COVID-19 epidemic was not significantly different from that during the COVID-19 epidemic. Interpersonal relationships (p = 0.03) and desire for research/critical thinking (p = 0.01) were significantly lower before the COVID-19 outbreak than during the COVID-19 outbreak. Only shift type had an association with clinical competency before the COVID-19 outbreak, while work experience had an association with clinical competency during the COVID-19 epidemic. Conclusion: The clinical competency among nurses was moderate before and during the COVID-19 epidemic. Paying attention to the clinical competence of nurses can improve the care conditions of patients, and nursing managers should improve the clinical competence of nurses in different situations and crises. Therefore, we suggest further studies identifying factors improving the professional competency among nurses. [ABSTRACT FROM AUTHOR]

Template matching is the fundamental task in remote sensing image processing of air- and space-based platforms. Due to the heterogeneous image sources, different scales and different viewpoints, the realization of a general end-to-end matching model is still a challenging task. Considering the abovementioned problems, we propose a cross-view remote sensing image matching method. Firstly, a spatial attention map was proposed to solve the problem of the domain gap. It is produced by two-dimensional Gaussian distribution and eliminates the distance between the distributed heterogeneous features. Secondly, in order to perform matching at different flight altitudes, a multi-scale matching method was proposed to perform matching on three down-sampling scales in turn and confirm the optimal result. Thirdly, to improve the adaptability of the viewpoint changes, a pixel-wise consensus method based on a correlation layer was applied. Finally, we trained the proposed model based on weakly supervised learning, which does not require extensive annotation but only labels one pair of feature points of the template image and search image. The robustness and effectiveness of the proposed methods were demonstrated by evaluation on various datasets. Our method accommodates three types of template matching with different viewpoints, including SAR to RGB, infrared to RGB, and RGB to RGB. [ABSTRACT FROM AUTHOR]

With the ongoing development of image technology, the deployment of various intelligent applications on embedded devices has attracted increased attention in the industry. One such application is automatic image captioning for infrared images, which involves converting images into text. This practical task is widely used in night security, as well as for understanding night scenes and other scenarios. However, due to the differences in image features and the complexity of semantic information, generating captions for infrared images remains a challenging task. From the perspective of deployment and application, to improve the correlation between descriptions and objects, we introduced the YOLOv6 and LSTM as encoder-decoder structure and proposed infrared image caption based on object-oriented attention. Firstly, to improve the domain adaptability of the detector, we optimized the pseudo-label learning process. Secondly, we proposed the object-oriented attention method to address the alignment problem between complex semantic information and embedded words. This method helps select the most crucial features of the object region and guides the caption model in generating words that are more relevant to the object. Our methods have shown good performance on the infrared image and can produce words explicitly associated with the object regions located by the detector. The robustness and effectiveness of the proposed methods were demonstrated through evaluation on various datasets, along with other state-of-the-art methods. Our approach achieved BLUE-4 scores of 31.6 and 41.2 on KAIST and Infrared City and Town datasets, respectively. Our approach provides a feasible solution for the deployment of embedded devices in industrial applications. [ABSTRACT FROM AUTHOR]

Chitin is a homopolymer of β-(1,4)-linked N-acetyl-D-glucosamine (GlcNAc) and a major structural component of fungal cell walls. In plants, chitin acts as a microbe-associated molecular pattern (MAMP) that is recognized by lysin motif (LysM)-containing plant cell surface-localized pattern recognition receptors (PRRs) that activate a plethora of downstream immune responses. To deregulate chitin-induced plant immunity and successfully establish infection, many fungal pathogens secrete LysM domain-containing effector proteins during host colonization. The LysM effector Ecp6 from the tomato (Solanum lycopersicum) leaf mold fungus Cladosporium fulvum can outcompete plant PRRs for chitin binding because two of its three LysM domains cooperate to form a composite groove with ultra-high (pM) chitin-binding affinity. However, most functionally characterized LysM effectors contain only two LysMs, including Magnaporthe oryzae MoSlp1, Verticillium dahliae Vd2LysM, and Colletotrichum higginsianum ChElp1 and ChElp2. Here, we performed modeling, structural, and functional analyses to investigate whether such dual-domain LysM effectors can also form ultra-high chitin-binding affinity grooves through intramolecular LysM dimerization. However, our study suggests that intramolecular LysM dimerization does not occur. Rather, our data support the occurrence of intermolecular LysM dimerization for these effectors, associated with a substantially lower chitin binding affinity than monitored for Ecp6. Interestingly, the intermolecular LysM dimerization allows for the formation of polymeric complexes in the presence of chitin. Possibly, such polymers may precipitate at infection sites to eliminate chitin oligomers, and thus suppress the activation of chitin-induced plant immunity. [ABSTRACT FROM AUTHOR]

This paper presents a closed-loop thrust control method for laboratory-scale hydrogen peroxide and polyethylene hybrid rocket motors. In this paper, the thrust is used as the feedback signal, and the oxidant flow adjustment is achieved by variable area cavitating venturi. The hot test based on thrust closed-loop control was carried out. The closed-loop control significantly improves the thrust control accuracy as demonstrated by the hot test with constant thrust. To obtain thrust closed-loop control parameters and improve control accuracy, a nonlinear increment proportional-integral-derivative algorithm is proposed. With the help of valve test parameters and thermodynamic calculation results, the method can directly obtain the control parameters of the thrust closed-loop control, which avoids the need for a large number of ground hot tests to debug the control parameters, and greatly reduces the test cost. For the purpose of improving thrust control accuracy, a linear variable area cavitating venturi was selected as the flow regulator and hydrogen peroxide and polyethylene were used as the propellant, which made the thrust approximately proportional to the flow rate. The experimental results show that the target thrust values of three stages in the test process are 400 N, 600 N and 400 N, the actual average thrust values are 399.8 N, 599.8 N and 400.8 N respectively, and the average thrust control accuracy is better than 0.5%. • The hot test based on thrust closed-loop control was carried out. • The closed-loop control significantly improves the thrust control accuracy as demonstrated by the hot test. • The segmented control strategy can greatly improve the response characteristics and shorten the regulation time. • The control method proposed in this paper is simple, low in cost and easy to implement. [ABSTRACT FROM AUTHOR]

In this article, a multilabel support vector machine (SVM)-based approach is investigated to address the simultaneous decay detection of the marine propulsion system. To verify the performance of the algorithm, we perform some experiments using a simulation data-set from a real-data validated numerical simulator of a Frigate. In particular, we try to train the model without simultaneous decay data, considering the great difficulty of obtaining simultaneous decay data in practice. The experimental results show that the proposed approach can identify the complex decay modes of the marine propulsion system effectively using only simple decay data in the training process. [ABSTRACT FROM AUTHOR]

Fungi play a critical role in silage and rumen fluid, both of which share similar ecosystems. This study is designed to supplement sweet sorghum ensiling with the rumen fluid from beef heifers and evaluate the effect on fungal diversity dynamics and silage quality by high-throughput sequencing and chemical methods. Simultaneously, this study investigated the correlation between fungal communities and chemical compositions of silages. The results suggested that the addition of rumen fluid significantly affected the richness and diversity of fungi in silage. Alpha diversity of total fungi and the relative abundance of Pichia increased, while Schizophyllum and Penicillium decreased, following the supplementation of rumen fluid during 60 days ensiling. In addition, the silage quality was positively correlated with Pichia, but negatively correlated with Hannaella and Vishniacozyma. The findings reveal that the rumen fluid can improve the ensiling characteristics by effectively reducing the reproduction of adverse fungi. However, further research is required to verify the connection of specific pure fungal isolates with the fermentation performance of silage. [ABSTRACT FROM AUTHOR]

Full phase manipulation with equal amplitude is critical for optical wavefront engineering in various systems. Here we theoretically explore a general approach for optical wavefront manipulation using dipolar metasurfaces under the coherent control. From the microscopic perspective, we theoretically show that the dispersion of a dipolar metasurface under the coherent control can provide the phase manipulation within a full range of [0, 2π] and retain an equal amplitude simultaneously. As an example, such a dipolar metasurface can be constructed by compensatory H-shaped unit resonators to avoid polarization conversion. Specifically, we confirm the feasibility of designed metasurfaces for achieving the beam bending and the vortex-phase beam by the full-wave simulation. The proposed approach enriches the well-established wavefront engineering for extending the functionality of metasurface under the coherent control. [ABSTRACT FROM AUTHOR]

Aero‐engine blades crack detection is one of the important tasks in daily ground maintenance, crack is a kind of texture feature, due to the random distribution, irregular shape and vague characteristics, which is still a challenging task to realize automatic detection in working environment. A detection model based on the Yolov4‐tiny is proposed that is universal and focuses more on the characteristics of cracks, and it is implemented in embedded device. First, in order to distinguish the cracks and noises, an improved attention module is introduced into the backbone of Yolov4‐tiny to enhance the model's capability to focus on crack areas; second, in order to improve the effect of multi‐scale feature fusion, the bicubic interpolation is implemented in upsampling module; finally, in order to solve the redundant detection results of bounding‐boxes in crack areas, the optimized non‐maximum suppression method is proposed to make the detection results better corresponding to the groundTruth. The robustness of proposed detection model was demonstrated by evaluating varying lighting and noise images. The average precision on integrated datasets is 81.6%, which outperforms the original Yolov4‐tiny by an increase of 12.3%. [ABSTRACT FROM AUTHOR]

Spermatogenesis is precisely controlled by complex gene-expression programs. During mammalian male germ-cell development, a crucial feature is the repression of transcription before spermatid elongation. Previously, we discovered that the RNA-binding protein EWSR1 plays an important role in meiotic recombination in mouse, and showed that EWSR1 is highly expressed in late meiotic cells and post-meiotic cells. Here, we used an Ewsr1 pachytene stage-specific knockout mouse model to study the roles of Ewsr1 in late meiotic prophase I and in spermatozoa maturation. We show that loss of EWSR1 in late meiotic prophase I does not affect proper meiosis completion, but does result in defective spermatid elongation and chromocenter formation in the developing germ cells. As a result, male mice lacking EWSR1 after pachynema are sterile. We found that, in Ewsr1 CKO round spermatids, transition from a meiotic gene-expression program to a post-meiotic and spermatid gene expression program related to DNA condensation is impaired, suggesting that EWSR1 plays an important role in regulation of spermiogenesis-related mRNA synthesis necessary for spermatid differentiation into mature sperm. [ABSTRACT FROM AUTHOR]

Due to the impact of human agricultural production and climate and environmental changes, the suitability of groundwater for drinking purposes has attracted widespread attention. In order to quantify the hydrochemical characteristics of groundwater in Hailun and evaluate its suitability for drinking purposes, 55 groundwater samples were collected and analyzed. The results show that groundwater in aquifers in the study area is weakly alkaline. The content is in the order HCO3-> Cl-> SO42- for anions, and Ca2+> Na+> Mg2+ for cations. Groundwater chemical type were dominated by HCO3-Ca• Mg, HCO3-Ca• Na, HCO3-Ca, and HCO3 - Ca • Mg • Na. The Gibbs plot, PCA, and CAI-1 index show that ion exchange, rock weathering and evaporation crystallization are the main reasons affecting the water chemical composition in Hailun. The analysis of water samples based on the WQI model revealed that about 69.09%, 25.45%, 1.81%, and 3.63% of the water samples were excellent, good, very poor, and unsuitable for drinking purposes, respectively. The spatial distribution map of water quality index show that most of the groundwater resources in the study area are not polluted and therefore suitable for drinking. [ABSTRACT FROM AUTHOR]

The economically adaptable mulberry (Morus alba L.) has a long history of grafting in China, yet the physiological mechanisms and advantages in drought tolerance remain unexplored. In our study, we investigated the responses of self-rooted 2X (diploid), 3X (triploid), and 4X (tetraploid) plants, as well as polyploid plants grafted onto diploid seedling rootstocks (2X/2X, 3X/2X, and 4X/2X) under drought stress. We found that self-rooted diploid plants exhibited the most severe phenotypic damage, lowest water retention, photosynthetic capacity, and the least effective osmotic stress adjustment compared to tetraploid and triploid plants. However, grafted diploid and triploid plants showed effective mitigation of drought-induced damage, with higher relative water content and improved soil water retention. Grafted plants also improved the photosystem response to drought stress through elevated photosynthetic potential, closed stomatal aperture, and faster recovery of chlorophyll biosynthesis in the leaves. Additionally, grafted plants altered osmotic protective compound levels, including starch, soluble sugar, and proline content, thereby enhancing drought resistance. Absolute quantification PCR indicated that the expression levels of proline synthesis-related genes in grafted plants were not influenced after drought stress, whereas they were significantly increased in self-rooted plants. Consequently, our findings support that self-rooted triploid and tetraploid mulberries exhibited superior drought resistance compared to diploid plants. Moreover, grafting onto seedling rootstocks enhanced tolerance against drought stress in diploid and triploid mulberry, but not in tetraploid. Our study provides valuable insights for a comprehensive analysis of physiological effects in response to drought stress between stem-roots and seedling rootstocks. • Tetraploid and triploid plants tolerate drought stress better than diploid plants in self-rooted mulberries. • Grafting further enhances the drought tolerance of diploid and triploid plants. • Grafting probably confers enhanced drought tolerance to the plants through seedling rootstocks. [ABSTRACT FROM AUTHOR]

Due to the impact of human agricultural production and climate and environmental changes, the applicability of groundwater for drinking purposes has attracted widespread attention. In order to quantify the hydrochemical characteristics of groundwater in Changchun New District and evaluate its quality for drinking purposes, 53 shallow groundwater samples were collected and analyzed. The results show that groundwater in aquifers in the study area is weakly alkaline. The abundance is in the order Ca2+ > Na+ > Mg2+ for cations, and HCO3− > Cl− > SO42− for anions. Ca-HCO3•Cl water type dominated the area, constituting about 26.41% of the total samples; Ca-HCO3 water type constituted about 22.64%; Ca•Na-HCO3 and Ca•Na-HCO3•Cl water types constituted 15.09% each, whereas Ca•Na-HCO3•Cl•SO4, Ca-HCO3•Cl•SO4, and Ca-SO4•Cl types made up 22.64% each. Correlation analysis (CA) and principal component analyses (PCA) show that rock weathering and dissolution, and human activities are the main reasons affecting the chemical composition of water in Changchun. The high concentrations of Pb, NO2−, Fe, and Mn must be widely concerned and may become the main environmental geological problems in the area. The analysis of water samples based on the water quality index model revealed that about 5.66%, 56.60%, 15.09%, 18.86%, and 3.77% of the shallow groundwater samples were excellent, good, poor, very poor, and unsuitable for drinking purposes, respectively. The analysis of groundwater samples based on the synthetic pollution index model showed that more than 37.74% of the groundwater samples were moderately polluted. The spatial distribution maps of the water quality index and the synthetic pollution index show that most of the shallow groundwater resources in the study area are clean and suitable for drinking, despite the risks of the shallow groundwater in the southeast of the study area. [ABSTRACT FROM AUTHOR]

The dynamic properties of the structure are related to many factors, such as mass distribution, component stiffness, material properties. In addition, environmental conditions may also affect the dynamic characteristics. In this paper, the modal identification of 133 strong earthquakes recorded in a 32-story SRC building structure in Tokyo from 2013 to 2018 is performed first, and then the dynamic characteristics (natural frequency, damping ratio) are obtained. The statistical regression analysis is used to analyze the influence of environmental conditions (temperature, humidity) on the dynamic characteristics of the high-rise SRC building structure, and the change trend of its dynamic characteristics. Finally, the results of the analysis are given to provide experience and basis for the design of similar building structures. [ABSTRACT FROM AUTHOR]

Ductility is an important aspect of the seismic performance of structures. Strong column and weak beam are important means to ensure the hinge plastic failure mechanism of frame structures. The corresponding provisions on failure mechanism of strong column-weak beam has been specified in design codes of various countries, but their differences are relatively large. This paper takes a plane frame as example which is designed according to the seismic code regulations of various countries, and then the difference in the failure mechanism of the designed frame under seismic actions is compared and analyzed. Finally, some suggestions are given to ensure the realization of strong column-weak beam mechanism. [ABSTRACT FROM AUTHOR]

We report a theoretical study on the Z-scan technique by using quasi-one-dimensional slit beam, when a nonlinear medium possesses third- and fifth-order nonlinearities simultaneously. For the case when the third- and fifth-order nonlinear refraction coefficients γ and γ′ have the same sign, we can extract both γ and γ′ from the empirical formula we found. When γ and γ′ have the opposite sign, a high-accuracy method was proposed to allow the determination of the nonlinear refraction coefficients related to the third- and fifth-order effects. We also find the empirical formulae, which can easily estimate the pure two-photon absorption coefficient and the pure three-photon absorption coefficient, respectively. [ABSTRACT FROM AUTHOR]

A composite grating structure composed of two-dimension SiC grating and multilayer films substrate is proposed. Surface phonon polariton is excited by the SiC grating to yield a absorption peaks at 10.6 μm. Ag and ZnS are selected to design multilayer films which have high absorption at 1.06 μm and high transmission for visible light. Meanwhile, the films has high spectral reflectance in the near, middle and far infrared band. By optimizing, the composite grating can satisfy the laser and infrared compatible stealth while achieving high visible transmittance. [ABSTRACT FROM AUTHOR]

>bold<>italic/italic<>/bold< The aim of this study was to investigate the association between body mass index (BMI) and prognosis of Chinese women with breast cancer. >bold<>italic/italic<>/bold< >bold<>italic/italic<>/bold< 3,380 primary breast cancer patients who underwent surgery from 2010 to 2012 were selected and classified as low BMI group (BMI < 25.0) and high BMI group (BMI ≥ 25.0). The follow-up data for disease-free survival (DFS) and overall survival (OS) were obtained from 3,178 patients (median follow-up of 58 months). Cox regression analysis was used to evaluate the effect of BMI on DFS and OS. >bold<>italic/italic<>/bold< The high BMI group showed more aggressive pathological features. BMI was negatively associated with OS (hazard ratio (HR) 1.33, 95% confidence interval (CI) 1.06–1.66; p = 0.012) but not DFS (HR 1.15, 95% CI 0.94–1.40; p = 0.17). Furthermore, when stratified by age, BMI was significantly and negatively associated with OS (HR 1.43, 95% CI 1.05–1.95; p = 0.025) in patients above 50 years of age, but this effect was not detected in younger patients. >bold<>italic/italic<>/bold< BMI was an independent prognostic factor of OS in Chinese women with breast cancer, and age might be a mitigating factor. Among patients above 50 years of age, those with a high BMI were at greater risk of poor prognosis compared to individuals with a low BMI. [ABSTRACT FROM AUTHOR]

Abstract Hybrid rocket motors is a promising propulsion system because of its intrinsic advantages over a conventional solid rocket motor and liquid rocket engine. However, serious nozzle erosion is a key problem that prevents hybrid rocket motors from being widely used, especially for propulsion systems with long operating times. In this paper, the erosion of a graphite-based nozzle coupled with a combustion flow field is studied in a hybrid rocket motor with a star grain. As the oxidizer and fuel, 90% hydrogen peroxide and hydroxide-terminated polybutadiene are adopted, respectively. The nozzle erosion was simulated coupled with the flow field in a typical hybrid rocket motor through three-dimensional numerical simulations. The simulations are based on a pure-gas steady numerical model considering turbulence, fuel pyrolysis, oxidizer/fuel reactions, thermal conduction and solid-gas boundary interactions on the fuel and nozzle surfaces. The results indicate that the nozzle erosion is greatly influenced by the inner flow field. The flame near the grain trough is thicker than that near the grain peak. Therefore, the maximum erosion rate (0.042 mm/s) occurs near the nozzle throat corresponding to the grain trough. The OH and H 2 O contribute 49.8% and 45.5% to the erosion rate, respectively, in this area. Furthermore, 56.6% and 31.9% contributions are made by OH and H 2 O, respectively, in the area corresponding to the grain peak. The O, CO 2 and O 2 make much lower contributions to the total erosion. In addition, a firing test is carried out to characterize the graphite nozzle erosion on a full-scale hybrid rocket motor with star grain. The nozzle inner profiles before and after test show that the erosion behavior of the graphite material is strictly related to the fuel shape. Highlights • Coupled simulations of flow field and nozzle erosion are conducted. • The effects of grain structure on nozzle erosion are studied with star-shape grain. • Heterogeneous reactions are considered to study the graphite nozzle erosion. • A numerical model for nozzle erosion in hybrid rocket motor is analyzed and tested. [ABSTRACT FROM AUTHOR]

Sepsis-induced skeletal muscle wasting may lead to various severe clinical consequences. Understanding molecular mechanisms of the regulation of the loss of skeletal muscle mass in septic patients remains a significant clinical challenge. The current study was conducted to establish septic mouse models to explore the relationship between microRNA (miR)-351 and the transcription element apical (TEA) domain transcription factor (Tead)-4 gene and to investigate its effects on the skeletal muscle through mediating the Hippo signaling pathway in mice with acute sepsis. A total of 60 mice were collected to establish mouse models of acute sepsis. The positive expression rate of Tead-4 and the apoptotic index (AI) were measured. A dual-luciferase reporter gene assay was conducted to verify the targeting relationship between miR-351 and Tead-4. Furthermore, the muscle fiber diameter (MFD) and area (MFA) and the content of 3-methylhistidine (3-MH) and tyrosine (Tyr) were assessed. The expression levels of miR-351, p38-MAPK, Yes-associated protein, Tead-4, B-cell lymphoma X protein (Bax), and Caspase-3 were determined with quantitative RT-PCR and Western blot analysis. Finally, cell viability, apoptosis, and levels of inflammatory factors, including IL-1β, IL-6, IGF-1, TNF-α, and monocyte chemoattractant protein-1 were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, and ELISA. Initially, Tead-4 protein expression was higher in skeletal muscle tissues of mice with acute sepsis. Tead-4 was identified to negatively regulate miR-351. Upregulation of miR-351 increased MFA and MFD, muscle weight water content, Bcl-2 expression levels, and cell viability. Up-regulation of miR-351 reduced AI; 3-MH and Tyr content; positive expression of Tead-4 protein; the expression levels of p38-MAPK, Yap, Tead-4, Bax, and Caspase-3; apoptosis; and inflammatory responses. The current study demonstrated that up-regulation of miR-351 inhibits the degradation of skeletal muscle protein and the atrophy of skeletal muscle in mice with acute sepsis by targeting Tead-4 through suppression of the Hippo signaling pathway. Thus, miR-351 overexpression may be a future therapeutic strategy for acute sepsis. [ABSTRACT FROM AUTHOR]

The output synchronisation of two deterministic Boolean networks coupled in the master-slave configuration is studied. First, under the algebraic framework of logical systems, an auxiliary system is constructed. Second, core input-state cycles are generalised and an algorithm is given to calculate these cycles. Third, based on core input-state cycles of the newly constructed auxiliary system, a necessary and sufficient existence condition is derived for a synchronising state feedback controller. Furthermore, a constructive method is provided to get feasible state feedback controllers when the existence condition obtained above is satisfied. Finally, an illustrative example is provided to verify the effectiveness and superiority of the presented results. [ABSTRACT FROM AUTHOR]

The cell-envelope protease PrtS was proved to be efficient in optimal bacterial growth and fast acidification in pure culture, while its positive effect on the performance of mixed-cultures in milk fermentation was not defined. The aim was to analyze effects of the PrtS on the symbiosis between strains during yoghurt production and cold storage. Two Streptococcus thermophilus strains, KLDS3.1012 and KLDS SM, and two different proteolytic strains of Lactobacillus delbrueckii subsp. Bulgaricus, L7 and L12, were used. Technological properties (viability, acid production, and proteolysis) were determined. Comparative genomics was used to analyze the proteolytic system (cell-envelope protease, transport system, intracellular peptidase) of Streptococcus thermophilus strains. S. thermophilus KLDS SM possesses an intact gene encoding PrtS (A9497_00420), which was not found in the genome of S. thermophilus KLDS3.1012. This gene is the main difference in the proteolytic system between the two genomes. PrtS endowed KLDS SM high levels of viability during fermentation and cold storage. When combined with a weaker lactobacillus strain during fermentation, the acceleration of acid production of mixed-culture by KLDS SM would start at an earlier time. KLDS SM increased the post-acidification of yoghurts during cold storage, but the pH was steadily maintained during 14-28 days. Results suggest that strains of Streptococcus thermophilus with strong proteolytic ability could be used in a wide range of dairy production. The present study provided data for yoghurt starter development from the point of view of proteolysis. [ABSTRACT FROM AUTHOR]

TheMDM2RING domain harbors E3 ubiquitin ligase activity critical for regulating the degradation of tumor suppressor p53, which controls many cellular pathways. The MDM2 RING domain also is required for an interaction with MDMX. Mice containing a substitution in the MDM2 RING domain, MDM2C462A, disrupting MDM2 E3 function and the MDMX interaction, die during early embryogenesis that can be rescued by p53 deletion. To investigate whether MDM2C462A, which retains p53 binding, has p53-suppressing activity, we generated Mdm2C462A/C462A;p53ER/- mice, in which we replaced the endogenous p53 alleles with an inducible p53ER/- allele, and compared survival with that of similarly generated Mdm2-/-;p53ER/- mice. Adult Mdm2-null mice died ∼7 days after tamoxifen-induced p53 activation, indicating that in the absence of MDM2,MDMX cannot suppress p53. Surprisingly, Mdm2C462A/C462A;p53ER/- mice died ∼5 days after tamoxifen injection, suggesting that p53 activity is higher in the presence of MDM2C462A than in the absence of MDM2. Indeed, in MDM2C462A-expressing mouse tissues and embryonic fibroblasts, p53 exhibited higher transcriptional activity than in those expressing no MDM2 or no MDM2 and MDMX. This observation indicated that MDM2C462A not only is unable to suppress p53 but may have gained the ability to enhance p53 activity. We also found that p53 acetylation, a measure of p53 transcriptional activity, was higher in the presence of MDM2C462A than in the absence of MDM2. These results reveal an unexpected role of MDM2C462A in enhancing p53 activity and suggest the possibility that compounds targetingMDM2RING domain function could produce even more robust p53 activation. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs/miRs) are a class of small, highly conserved non-coding RNAs that can serve either oncogenic or tumor-suppressive roles in a wide variety of tumors. miR-200c is a member of the miR-200 family whose specific role in non-small cell lung cancer (NSCLC) has not yet been elucidated. The purpose of the present study was to detect the expression level of miR-200c in NSCLC, and to analyze its association with clinicopathological factors and patient prognosis. The present study determined the expression levels of miR-200c in 110 tumor samples collected from patients diagnosed with NSCLC who underwent complete tumor resection with regional lymph node dissection, as assessed by reverse transcription-quantitative polymerase chain reaction. The association between the expression level of miR-200c and clinicopathological features and patient prognosis was also analyzed. The results showed that miR-200c overexpression was detected in 66 of the 110 cases and was significantly associated with positive lymph node metastasis (P<0.001). Univariate survival analysis demonstrated that high miR-200c expression, positive lymph node metastasis and advanced Tumor-Node-Metastasis (TNM) classification stage significantly predicted decreased 5-year disease-free survival rates (all P<0.05) and poor 5-year overall survival rates (all P<0.01), respectively. The results of multivariate Cox regression analysis showed that TNM stage and miR-200c expression retained its significance as an independent prognostic factor for unfavorable 5-year disease-free survival rates (P<0.05) and poor 5-year overall survival rates (P<0.01). The present findings suggest that miR-200c overexpression is significantly associated with poor survival rates in NSCLC and that miR-200c could play an oncogenic role. miR-200c may have clinical potential as a promising prognostic predictor for patients with NSCLC. [ABSTRACT FROM AUTHOR]

The seismic response of buildings is crucial for structural performance analysis. For structures with complete design data, the seismic response can be predicted using finite element analysis. However, for structures lacking necessary information, building finite element models and predicting their seismic response can be challenging. Compared to finite element analysis, convolutional neural networks (CNNs) can establish a neural network mapping relationship between the structure and the seismic response to predict the structural response without design data. In this paper, a structural response prediction model based on CNNs is established, aiming to analyze the effect of natural frequency reduction on the structural response after the Tohoku earthquake. The successful prediction of the structural acceleration and displacement response provides a new analytical method for predicting the seismic response of buildings lacking design data. [ABSTRACT FROM AUTHOR]

Mobile edge computing (MEC) has been deemed as one of the key technologies for pushing powerful computing ability to the radio access network. Different scenarios require different services, and tasks usually require computing in a specific runtime environment. However, few studies have taken this into consideration. To this end, the authors propose a novel model of service-dependent task offloading for the multiuser MEC system with resource constraints. Through determining which services should be deployed at the network edge and how many tasks should be offloaded, a revenue maximisation problem is constructed. Accordingly, they propose an iterative optimisation algorithm with high performance for the service deploying and task offloading problem. Finally, numerical simulations reveal that their proposed algorithm outperforms other schemes. [ABSTRACT FROM AUTHOR]

The expression of nitrate and ammonium transporter genes in the roots of winter wheat in response to drought stress is largely unknown. A greenhouse experiment was established to study the expression of five putative nitrate transporter (NRT) genes (TaNRT2.1, TaNRT2.2, TaNRT2.3, TaNRT1.1, TaNRT1.2) and three ammonium transporter (AMT) genes (TaAMT1.1, TaAMT1.2, TaAMT2.1) in the roots of winter wheat in response to soil drought under conditions of limited nitrogen (N) (no N added) and adequate N (addition of 0.3 g N kg-1 soil). Two wheat genotypes with low and high N-uptake efficiencies were used, and water-stress treatments were applied at the vegetative and reproductive growth stages of wheat. Expression of all of the genes was quantified using real-time reverse transcription PCR. The results indicated that wheat plants growing in the N-adequate soil were more sensitive to drought stress than those growing in the N-limited soil. The response of the expression of the NRT and AMT genes to soil drought largely depends on N application, wheat genotype and growth stage. The expression of the two low-affinity NRT genes (i.e. TaNRT1.1 and TaNRT1.2) in the N-inefficient genotype XY6 was mainly induced by drought stress, but the expression of the two genes in the N-efficient genotype XY107 was repressed by drought stress. The expression of the high-affinity NRT gene TaNRT2.1 was repressed by drought stress, but the expression of the other two high-affinity NRT genes, TaNRT2.2 and TaNRT2.3, was induced or repressed by soil drought depending on N application and growth stage. The expression of the genes TaAMT1.1 and TaAMT2.1 was mainly repressed by drought stress, whereas the expression of the gene TaAMT1.2 was induced by drought stress. The expression of TaNRT2.1 in XY107 was significantly higher than in XY6. [ABSTRACT FROM AUTHOR]

Based on previous findings regarding the angiogenic activities and prognostic roles of metastasis-associated protein 1 (MTA1) in early-stage non-small cell lung cancer, the clinicopathological and prognostic significance of MTA1 protein expression, and its correlation with angiogenesis in lung invasive adenocarcinoma, were further assessed in the present study, according to the 2011 International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification. High protein expression levels of MTA1 were commonly observed in patients with lung invasive adenocarcinoma, and were significantly correlated with tumor size (P=0.030), lymph node metastasis (P=0.021) and microvessel density (P=0.015). Survival analysis demonstrated that patients with high protein expression levels of MTA1 exhibited significantly shorter five-year disease-free and overall survival than those patients whose protein expression levels of MTA1 were low (24.5% vs. 48.7%, P=0.001, and 34.7% vs. 59.2%, P=0.005, respectively). In addition, Cox regression multivariate analysis demonstrated that high protein expression levels of MTA1 significantly correlated with unfavorable five-year disease-free survival (P=0.024). These findings indicate that MTA1 protein expression may possess clinical potential as an indicator of progressive phenotype. Therefore, MTA1 is a promising prognostic predictor to identify subgroups of patients with high risk of relapse, and a potentially novel therapeutic target for antiangiogenesis in patients with lung invasive adenocarcinoma. [ABSTRACT FROM AUTHOR]

Theneighboring layers in bilayer (and few-layer) graphenes of both AAand AB stacking motifs are known to be separated at a distance correspondingto van der Waals (vdW) interactions. In this Letter, we present forthe first time a new aspect of graphene chemistry in terms of a specialchemical bonding between the giant graphene “molecules”.Through rigorous theoretical calculations, we demonstrate that theN-doped graphenes (NGPs) with various doping levels can form an unusualtwo-dimensional (2D) π–π bonding in bilayer NGPsbringing the neighboring NGPs to significantly reduced interlayerseparations. The interlayer binding energies can be enhanced by upto 50% compared to the pristine graphene bilayers that are characterizedby only vdW interactions. Such an unusual chemical bonding arisesfrom the π–π overlap across the vdW gap while theindividual layers maintain their in-plane π-conjugation andare accordingly planar. The existence of the resulting interlayercovalent-like bonding is corroborated by electronic structure calculationsand crystal orbital overlap population (COOP) analyses. In NGP-basedgraphite with the optimal doping level, the NGP layers are uniformlystacked and the 3D bulk exhibits metallic characteristics both inthe in-plane and along the stacking directions. [ABSTRACT FROM AUTHOR]

Primary spontaneous pneumothorax recurs at a certain rate after thoracoscopic surgery, and risk factors for that recurrence are in question. The medical records of 248 patients with primary spontaneous pneumothorax who were followed for more than 2 years after thoracoscopic surgery were reviewed and retrospectively analyzed. Univariate and multivariate binary logistic regression analysis were used to identify possible risk factors. Twelve patients experienced the recurrence of primary spontaneous pneumothorax. Patients who experienced the recurrence of primary spontaneous pneumothorax were younger than patients who experienced no recurrence. A larger proportion of the patients who experienced recurrence did not undergo pleurodesis. The variables age, height, weight, body mass index, duration of air leakage, and pleurodesis (performed or not) with a p value less than 0.2 in univariate analysis were entered in multivariate analysis. A younger age and not undergoing pleurodesis were associated with a higher risk of postoperative ipsilateral recurrence of primary spontaneous pneumothorax. Not undergoing pleurodesis and a younger age are possible risk factors for recurrence of primary spontaneous pneumothorax after thoracoscopic surgery. Thoracic surgeons should pay more attention to pleurodesis, especially in younger patients. [ABSTRACT FROM AUTHOR]

In this paper, density functional theory (DFT) calculation was employed to study the adsorption of nitric oxide (NO) on the highly reactive anatase TiO2 (001) surface. For comparison, the adsorption of NO on the (101) surface was also considered. Different from the physical adsorption on the (101) surface, NO molecules are found to chemisorb on the TiO2 (001) surface. The twofold coordinate oxygen atoms (O2c) on the anatase (001) surface are the active sites. Where NO is oxidized into a nitrite species (NO2-) trapping efficiently on the surface, with one of the surface Ti5c-O2c bonds adjacent to the adsorption site broken. Our results, therefore, supply a theoretical guidance to remove NO pollutants using highly reactive anatase TiO2 (001) facets. [ABSTRACT FROM AUTHOR]

The variable area cavitating venturi is an effective means to throttle the mass flow rate of liquid. The mass flow rate is a function of the upstream pressure, the pintle stroke, the density and saturation pressure of the liquid, independent of the downstream pressure. In this paper, a variable area cavitating venturi is designed and four different sets of experiments are conducted to investigate the performance of the variable area cavitating venturi. In these experiments, the mass flow rates are examined under different pintle positions, upstream pressures, downstream pressures and dynamic motions of the pintle. The experimental results indicate that the mass flow rate is independent of the downstream pressure when the ratio of the downstream pressure to upstream pressure is less than 0.8. The mass flow rate is almost linearly dependent on the pintle stroke for a constant upstream pressure. The discharge coefficient is a function of the pintle stroke, whereas the upstream and downstream pressures have rare influence on the discharge coefficient. The variable area cavitating venturi can control and measure the mass flow rate dynamically by determining the pintle stroke and the upstream pressure. [ABSTRACT FROM AUTHOR]

Recently, Nishibayashi et al. reported a dimolybdenum-dinitrogen complex that is catalytic for complete reduction of dinitrogen to ammonia. This catalyst is different from the Schrock molybdenum catalyst in two fundamental aspects: it contains two metal centers, and the oxidation state is Mo0 instead of MoIII. We show that a remarkable feature of the bimetallic complex is the bond-mediated delocalized electronic states, resulting from the two metal centers bridged by a dinitrogen ligand. Using first-principles calculations, we found that this property makes the bimetallic complex the effective catalyst, as opposed to the originally postulated monometallic fragment. A favorable reaction pathway is identified, and the nature of the intermediates is examined. Furthermore, studies of the intermediate states led us to propose possible deactivation processes of the catalyst. The finding that the central bimetallic unit (Mo-N2-Mo) is relevant for catalytic activity may provide a guideline for the development of more efficient dinitrogen-reducing catalysts. [ABSTRACT FROM AUTHOR]

This paper presents a dynamic adaptive machine-to-machine (M2M) service rate allocation scheme for optimum traffic distribution in heterogeneous wireless environments (HWEs). According to the M2M service characteristics, it proposes the utility function, which forms a convex optimization problem that maximizes the utility of M2M service and can be solved by the Lagrange multiplier. The simulation results show the proposed method convergence, and it can achieve load balance with maximized throughput and minimized cost. [ABSTRACT FROM AUTHOR]

Wavefront distortions pose a significant limitation in various optical applications, hindering further advancements in optical system performance. In this study, a novel generic calibration model based on Zernike‐fitting neural network (ZFNN) is proposed, which enables insitu wavefront correction with just a single‐shot measurement. The experimental setup follows a standard or equivalent focal‐field imaging optical path, allowing calibration without the need to remove any components from the optical system. The ZFNN, a physics‐informed neural network, offers the advantage of not requiring prior training, eliminating the need for extensive labeled data. With a fully connected network architecture and a modest number of neurons (469), the ZFNN achieves exceptionally fast optimization speed and meets the basic requirements for real‐time calibration. Consequently, this approach holds great potential for applications such as rapid calibration of optical systems, high‐precision light field modulation, and various advanced imaging techniques. [ABSTRACT FROM AUTHOR]

MDA-7/IL-24 was involved in the specific cancer apoptosis through suppression of Bcl-2 expression, which is a key apoptosis regulatory protein of the mitochondrial death pathway. However, the underlying mechanisms of this regulation are unclear. We report here that tumor-selective replicating adenovirus ZD55-IL-24 leads to Bcl-2 S-denitrosylation and concomitant ubiquitination, which take part in the 26S proteasome degradation. IL-24-siRNA completely blocks Bcl-2 ubiquitination via reversion of Bcl-2 S-denitrosylation and protects it from proteasomal degradation which confirmed the significant role of MDA-7/IL-24 in regulating posttranslational modification of Bcl-2 in cancer cells. Nitric oxide (NO) is a key regulator of protein S-nitrosylation and denitrosylation. The NO donor, sodium nitroprusside (SNP), down-regulates Bcl-2 Sdenitrosylation, attenuates Bcl-2 ubiquitination and subsequently counteracts MDA-7/IL-24 induced cancer cell apoptosis, whereas NO inhibitor 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxy-3-oxide (PTIO) shows the opposite effect. At the same time, these NO modulators fail to affect Bcl-2 phosphorylation, suggesting that NO regulates Bcl-2 stability in a phosphorylation-independent manner. In addition, Bcl-2 S-nitrosylation reduction induced by ZD55-IL-24 was attributed to both iNOS decrease and TrxR1 increase. iNOS-siRNA facilitates Bcl-2 S-denitrosylation and ubiquitin-degradation, whereas the TrxR1 inhibitor auranofin prevents Bcl-2 from denitrosylation and ubiquitination, thus restrains the caspase signal pathway activation and subsequent cancer cell apoptosis. Taken together, our studies reveal that MDA-7/IL-24 induces Bcl-2 S-denitrosylation via regulation of iNOS and TrxR1. Moreover, denitrosylation of Bcl-2 results in its ubiquitination and subsequent caspase protease family activation, as a consequence, apoptosis susceptibility. These findings provide a novel insight into MDA-7/IL-24 induced growth inhibition and carcinoma apoptosis. [ABSTRACT FROM AUTHOR]

This analysis begins to explore the complex chromosphere-corona mass cycle using a blend of imaging and spectroscopic diagnostics. Single Gaussian fits (SGFs) to hot emission line profiles (formed above 1MK) at the base of coronal loop structures indicate material blueshifts of 5-10 km s-1, while cool emission line profiles (formed below 1 MK) yield redshifts of a similar magnitude--indicating, to zeroth order, that a temperature-dependent bifurcating flow exists on coronal structures. Image sequences of the same region reveal weakly emitting upward propagating disturbances in both hot and cool emission with apparent speeds of 50-150 km s-1. Spectroscopic observations indicate that these propagating disturbances produce a weak emission component in the blue wing at commensurate speed, but that they contribute only a few percent to the (ensemble) emission line profile in a single spatio-temporal resolution element. Subsequent analysis of imaging data shows material "draining" slowly (~10 km s-1) out of the corona, but only in the cooler passbands. We interpret the draining as the return flow of coronal material at the end of the complex chromosphere-corona mass cycle. Further, we suggest that the efficient radiative cooling of the draining material produces a significant contribution to the red wing of cool emission lines that is ultimately responsible for their systematic redshift as derived from an SGF when compared to those formed in hotter (conductively dominated) domains. The presence of counterstreaming flows complicates the line profiles, their interpretation, and asymmetry diagnoses, but allows a different physical picture of the lower corona to develop. [ABSTRACT FROM AUTHOR]

Solar eruptions, particularly coronal mass ejections (CMEs) and extreme-ultraviolet (EUV) jets, have rarely been investigated with spectroscopic observations. We analyze several data sets obtained by the EUV Imaging Spectrometer on board Hinode and find various types of flows during CMEs and jet eruptions. CME-induced dimming regions are found to be characterized by significant blueshift and enhanced line width by using a single Gaussian fit, while a red-blue (RB) asymmetry analysis and an RB-guided double Gaussian fit of the coronal line profiles indicate that these are likely caused by the superposition of a strong background emission component and a relatively weak (~10%), high-speed (~100 km s-1) upflow component. This finding suggests that the outflow velocity in the dimming region is probably of the order of 100 km s-1, not ~20 km s-1 as reported previously. These weak, high-speed outflows may provide a significant amount of mass to refill the corona after the eruption of CMEs, and part of them may experience further acceleration and eventually become solar wind streams that can serve as an additional momentum source of the associated CMEs. Density and temperature diagnostics of the dimming region suggest that dimming is primarily an effect of density decrease rather than temperature change. The mass losses in dimming regions as estimated from different methods are roughly consistent with each other, and they are 20%-60% of the masses of the associated CMEs. With the guide of RB asymmetry analysis, we also find several temperature-dependent outflows (speed increases with temperature) immediately outside the (deepest) dimming region. These outflows may be evaporation flows that are caused by the enhanced thermal conduction or nonthermal electron beams along reconnecting field lines, or induced by the interaction between the opened field lines in the dimming region and the closed loops in the surrounding plage region. In an erupted CME loop and an EUV jet, profiles of emission lines formed at coronal and transition region temperatures are found to exhibit two well-separated components, an almost stationary component accounting for the background emission and a highly blueshifted (~200 km s-1) component representing emission from the erupting material. The two components can easily be decomposed through a double Gaussian fit, and we can diagnose the electron density, temperature, and mass of the ejecta. Combining the speed of the blueshifted component and the projected speed of the erupting material derived from simultaneous imaging observations, we can calculate the real speed of the ejecta. [ABSTRACT FROM AUTHOR]

We show that pancake bonding in radical π-dimers display features of charge shift (CS) bonding. While the CS bonding concept has been developed to interpret the unusual aspects of σ-bonds around centers with a large number of lone pairs, such as F2 and HOOH, we find a similar role played by the nonbonding or slightly bonding π-electron pairs in π-stacking radical dimers. Arguments and computational evidence indicate that the CS bonding concept developed by Shaik and Hiberty et al. captures essential features of the intermolecular bonding in radical π-dimers in which the overlap of the two radical centered singly occupied molecular orbitals (SOMOs) play a crucial role. By using the tetracyanoethylene anion dimer, Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed., as a model, we show that compared to CAS(2,2) calculations, significant binding contributions are recovered in the calculations simply by including selected intrapair excitations of the SOMO-SOMO bonding orbitals and the nonbonding π-orbitals. This observation is the basis for the analogy of chemical bonding between pancake bonded radical π-dimers and other charge shift bonded molecules, such as F2. By extending the CS bonding concept to a new class of molecules, we find a novel application of the lone pair bond weakening effect (LPBWE) in which the doubly occupied π-orbitals play the role of lone pairs. [ABSTRACT FROM AUTHOR]

Recent spectroscopic observations have revealed the ubiquitous presence of blueward asymmetries of emission lines formed in the solar corona and transition region. These asymmetries are most prominent in loop footpoint regions, where a clear correlation of the asymmetry with the Doppler shift and line width determined from the single-Gaussian fit is found. Such asymmetries suggest at least two emission components: a primary component accounting for the background emission and a secondary component associated with high-speed upflows. The latter has been proposed to play a vital role in the coronal heating process and there is no agreement on its properties. Here we slightly modify the initially developed technique of red-blue (RB) asymmetry analysis and apply it to both artificial spectra and spectra observed by the Extreme-ultraviolet Imaging Spectrometer on board Hinode, and demonstrate that the secondary component usually contributes a few percent of the total emission, and has a velocity ranging from 50 to 150 km s-1 and a Gaussian width comparable to that of the primary one in loop footpoint regions. The results of the RB asymmetry analysis are then used to guide a double-Gaussian fit and we find that the obtained properties of the secondary component are generally consistent with those obtained from the RB asymmetry analysis. Through a comparison of the location, relative intensity, and velocity distribution of the blueward secondary component with the properties of the upward propagating disturbances revealed in simultaneous images from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we find a clear association of the secondary component with the propagating disturbances. [ABSTRACT FROM AUTHOR]

Observations from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory reveal ubiquitous episodic outflows (jets) with an average speed around 120 km s-1 at temperatures often exceeding a million degree in plume-like structures, rooted in magnetized regions of the quiet solar atmosphere. These outflows are not restricted to the well-known plumes visible in polar coronal holes, but are also present in plume-like structures originating from equatorial coronal holes and quiet-Sun (QS) regions. Outflows are also visible in the "inter-plume" regions throughout the atmosphere. Furthermore, the structures traced out by these flows in both plume and inter-plume regions continually exhibit transverse (Alfvénic) motion. Our finding suggests that high-speed outflows originate mainly from the magnetic network of the QS and coronal holes (CHs), and that the plume flows observed are highlighted by the denser plasma contained therein. These outflows might be an efficient means to provide heated mass into the corona and serve as an important source of mass supply to the solar wind. We demonstrate that the QS plume flows can sometimes significantly contaminate the spectroscopic observations of the adjacent CHs--greatly affecting the Doppler shifts observed, thus potentially impacting significant investigations of such regions. [ABSTRACT FROM AUTHOR]

Abstract: We analyze the propagation of Laguerre–Gaussian (LG) beams in a cubic–quintic nonlinear medium by using the variational method. For low intensities, the results are in good agreement with the results of a numerical simulation. The characteristics of LG beams in the nonlinear medium are explored and the electric field distribution in the far field after passing through the nonlinear medium is calculated. [Copyright &y& Elsevier]

O-Acetylserine sulfhydrylase is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes the final step in the cysteine biosynthetic pathway in enteric bacteria and plants, the replacement of the β- acetoxy group of O-acetyl-L-serine (OAS) by a thiol to give L-cysteine. Previous studies of the K4 IA mutant enzyme showed L-methionine bound in an external Schiff base (ESB) linkage to PLP as the enzyme was isolated. The mutant enzyme exists in a closed form, optimizing the orientation of the cofactor PLP and properly positioning active site functional groups for reaction. The trigger for closing the active site upon formation of the ESB is thought to be interaction of the substrate α-carboxylate with the substrate-binding loop comprised of T68, S69, G70, and N71,and QI 42, which is positioned above the cofactor as one looks into the active site. To probe the contribution of these residues to the active site closing and orientation of PLP in the ESB, T68, S69, N71, and Ql42 were changed to alanine. Absorbance, fluorescence, near UV-visible CD, and 31P NMR spectral studies and pre-steady state kinetic studies were used to characterize the mutant enzymes. All of the mutations affect closure of the active site, but to differing extents. In addition, the site appears to be more hydrophilic given that the ESBs do not exhibit a significant amount of the enolimine tautomer. No buildup of the a-aminoacrylate intermediate (AA) is observed for the T68A and QI 42A mutant enzymes. However, pyruvate is produced at a rate much greater than that of the wild-type enzyme. Data suggest that T68 and Q142 play a role in stabilizing the AA. Both residues donate a hydrogen bond to one of the carboxylate oxygens of the methionine ESB and may also be responsible for the proper orientation of the ESB to generate the AA. The S69A and N71 A mutants exhibit formation of the AA, but the rate constant for its formation from the ESB is decreased by I order of magnitude compared to that of the wild type. S69 donates a hydrogen bond to the substrate carboxylate in the ESB, while N71 donates hydrogen bonds to 03' of the cofactor and the carboxylate of the ESB; these side chains may also affect the-orientation of the ESB. Data suggest that interaction of intermediates with the substrate-binding loop and QI42 gives a properly aligned Michaelis complex and facilitates the β-elimination reaction. [ABSTRACT FROM AUTHOR]

Abstract: In the next generation heterogeneous wireless networks, a mobile terminal (MT) with a multi-interface may have network access from different service providers using various technologies. In spite of this heterogeneity, seamless intersystem mobility is a mandatory requirement. One of the major challenges for seamless mobility is the creation of a vertical handover scheme, which is for users that move between different types of networks. In this article a seamless mobility handover scheme is presented. The novelty of the proposed scheme is that handover is fully controlled by the terminal. To improve the performance of the proposed handover scheme, a network discovery algorithm with fuzzy logic and a handover decision algorithm using multi criteria decision making (MCDM) based on vague sets are derived, which are both user-centric. With these algorithms, the handover scheme is power-saving, cost-aware, and performance-aware. Simulation results show that the novel handover scheme can perform network discovery in time to reduce handover dropping rate and present unnecessary activation of its interface to save the battery power, while effectively choose the optimum network through making trade-off among the user preference, network condition, and system performance. [Copyright &y& Elsevier]