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Carbonaceous aerosols (CA) from anthropogenic emissions have been significantly reduced in urban China in recent years. However, the relative contributions of fossil and nonfossil sources to CA in rural and background regions of China remain unclear. In this study, the sources of different carbonaceous fractions in fine aerosols (PM2.5) from five background sites of the China Meteorological Administration Atmosphere Watch Network during the winter of 2019 and 2020 were quantified using radiocarbon (14C) and organic markers. The results showed that nonfossil sources contributed 44–69% to total carbon at these five background sites. Fossil fuel combustion was the predominant source of elemental carbon at all sites (73 ± 12%). Nonfossil sources dominated organic carbon (OC) in these background regions (61 ± 13%), with biomass burning or biogenic-derived secondary organic carbon (SOC) as the most important contributors. However, the relative fossil fuel source to OC in China (39 ± 13%) still exceeds those at other regional/background sites in Asia, Europe, and the USA. SOC dominated the fossil fuel-derived OC, highlighting the impact of regional transport from anthropogenic sources on background aerosol levels. It is therefore imperative to develop and implement aerosol reduction policies and technologies tailored to both the anthropogenic and biogenic emissions to mitigate the environmental and health risks of aerosol pollution across China.

In the emerging high-tech industry, the number of patents is growing particularly rapidly. In this background, timely and accurate identification of patents that are closely related to enterprises and have significant influence for realising patent transformation and promoting enterprise development. In this paper, we propose a recommendation method based on co-occurrence network and Point Mutual Information coefficient (PMI). Through experiments on the patent texts in the communication industry, this paper finds that the patents recommended are highly compatible with the development direction of the enterprise, which can provide high value for the development of the enterprise. It verifies that the method of this paper is valid in the field of patent recommendation, and provides new ideas for improving the conversion rate of patents and promoting the application of scientific and technological achievements.

This article presents a novel ultrawideband (UWB) antenna for multiple-input-multiple-output (MIMO) operations in wireless capsule endoscopy (WCE) applications. The design is capable of supporting high channel capacity for real-time transmission and addressing the frequency detuning effect. Thanks to the conformal meander structure, the design efficiently uses the inner wall space of the capsule, achieving both compactness and wideband operation. The proposed MIMO antenna consists of two elements, each occupying a volume of 7.192 mm3. The experimental measurements are performed inside a minced pork meat. The antenna covers a bandwidth range from 0.61 to 1.51 GHz, achieving a fractional bandwidth (FBW) of 84.91% and a peak gain of −30.4 dBi. An isolation level greater than 20 dB is maintained, indicating low mutual coupling between MIMO antenna elements. The specific absorption rate (SAR) is evaluated to be 0.0202 W/kg at a transmitted power of −16 dBm, and the link margin (LM) is calculated to be 20 dB at a distance of 2 m. Therefore, the proposed bio-telemetry system confirms its suitability for safe and high data rate communications.

ZrB2-based ceramic composites were prepared by spark plasma sintering using ZrB2powder prepared by molten salt method as raw material and SiC and nano-graphite as additives. The effects of nano-graphite addition on the physical properties and oxidation resistance of ZrB2-based ceramic samples were investigated. The results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of ZrB2-based ceramic composites and improve the physical properties of the materials. The flexural strength of the ceramic sample with 8 vol.% nano-graphite reached 418.54 MPa, which was 53.14% higher than that of ZrB2–SiC ceramic material (273.31 MPa), and its oxidation resistance was also significantly improved. It demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of ZrB2–SiC ceramic composites. Via prolonging its service life in application and promoting the development of ZrB2-based ceramic composites, it is of great significance for clean steel smelting.

Looking back on the development of radiomics in osteosarcoma over recent years, in addition to distinguishing osteosarcoma from other malignant bone tumors (mainly Ewing's sarcoma), more research directions are using radiomics to evaluate and predict the efficacy and survival of patients undergoing neoadjuvant chemotherapy. Among the three commonly used examination methods of X‐ray, CT, and magnetic resonance imaging (MRI), more and more studies have been conducted on MRI‐based radiomics, which fully reflects the advantages of MRI's high soft tissue contrast, multi‐sequence imaging, and most of the studies used a combination of imaging features and clinical features to make predictions. Some articles also considered relevant laboratory examination results and more and more studies are performing external verification. The field is now gradually developing toward multidimensional data and multicenter cooperation and data sharing. Osteosarcoma is the most common primary malignant bone tumor, often associated with a poor natural prognosis. Imaging techniques such as X‐ray, computed tomography, and magnetic resonance imaging have become essential tools in the diagnosis and treatment of osteosarcoma. The development of imaging informatics techniques, including machine learning and deep learning, has enhanced the role of medical imaging in assisting physicians with early diagnosis and treatment evaluation. This advancement further improves the diagnosis and treatment of osteosarcoma patients, facilitating more personalized care.

Objective:The aim of this study was to compare Biatain Ag and Biatain Alginate Ag (both Coloplast, Denmark) as skin graft donor site dressings.Method:A single-centre, prospective, randomised clinical study was conducted. In patients who had undergone a skin graft operation, adjacent split-thickness skin graft donor sites were dressed with Biatain Ag and Biatain Alginate Ag, respectively. The primary outcomes were time to re-epithelialisation and pain score after the operation. The secondary outcomes were scar scores of the donor site after the operation, haematoma rates, infection rates, and exudation rates before wound healing. Results were compared using the Wilcoxon test and the Chi-squared test.Results:A total of 16 paired wounds in 16 patients were studied. The donor sites dressed with Biatain Ag needed more time for >90% re-epithelialisation than those dressed with Biatain Alginate Ag. On day 3 postoperatively, the pain scores with Biatain Ag were significantly less severe than those with Biatain Alginate Ag. On days 6, 9 and 12, the pain scores of both dressings did not differ significantly. The scar scores of the donor site dressed with Biatain Ag were significantly worse than those dressed with Biatain Alginate Ag at 6 months. With respect to infection rates, no significant differences were detected between these two groups. However, the exudation rates of the donor site dressed with Biatain Ag were significantly lower than those dressed with Biatain Alginate Ag.Conclusion:As skin graft donor site dressings, both Biatain Ag and Biatain Alginate Ag have advantages.

Diabetic patients receiving the antidiabetic drug metformin have been observed to exhibit a lower prevalence of anxiety disorders, yet the precise mechanism behind this phenomenon is unclear. In our study, we found that anxiety induces a region-specific reduction in AMPK activity in the medial prefrontal cortex (mPFC). Concurrently, transgenic mice with brain-specific AMPK knockout displayed abnormal anxiety-like behaviors. Treatment with metformin or the overexpression of AMPK restored normal AMPK activity in the mPFC and mitigated social stress-induced anxiety-like behaviors. Furthermore, the specific genetic deletion of AMPK in the mPFC not only instigated anxiety in mice but also nullified the anxiolytic effects of metformin. Brain slice recordings revealed that GABAergic excitation and the resulting inhibitory inputs to mPFC pyramidal neurons were selectively diminished in stressed mice. This reduction led to an excitation-inhibition imbalance, which was effectively reversed by metformin treatment or AMPK overexpression. Moreover, the genetic deletion of AMPK in the mPFC resulted in a similar defect in GABAergic inhibitory transmission and a consequent hypo-inhibition of mPFC pyramidal neurons. We also generated a mouse model with AMPK knockout specific to GABAergic neurons. The anxiety-like behaviors in this transgenic mouse demonstrated the unique role of AMPK in the GABAergic system in relation to anxiety. Therefore, our findings suggest that the activation of AMPK in mPFC inhibitory neurons underlies the anxiolytic effects of metformin, highlighting the potential of this primary antidiabetic drug as a therapeutic option for treating anxiety disorders.

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In developing countries, the management of chronic diseases in the elderly is challenging because of limited medical resources and a large population. Hospitals cannot quickly provide treatment for chronic diseases for the elderly. This article discusses a mobile-medical-based system that uses effective data decision-making and wireless network communication to assist the elderly in implementing remote medical services and proposes a deep learning model-combined sparse autoencoder (CSAE) in the decision-making module. The model uses sparse autoencoders to process patient detection data and monitoring data collaboratively to achieve multisource data association and fusion. The prediction probability of diseases is obtained through deep neural networks and a classifier, and the best disease prediction sequence is output to realize the prediction and early warning of chronic diseases. In the experimental part, we compare CSAE with the other four machine learning classification algorithms in terms of accuracy, sensitivity, and specificity. The results prove that CSAE is superior to other algorithms in the single-disease prediction, with the accuracy and specificity exceeding 85%, and the sensitivity not lower than 75%. When predicting multiple diseases, our proposed algorithm's performance is the most stable, with an accuracy higher than other algorithms by more than 10%.

In the present study, arrayed nano-precipitated TiC in a ferrite matrix was obtained through thermal treatment. The size and shape of the arrayed interphase nano-precipitates were unaffected by fatigue deformation in this Ti-microalloyed steel. In addition, arrayed arrangement of the interphase nano-precipitates was not disrupted by fatigue and still remained only at low cycle numbers, which corresponded to the shortest fatigue life. The interphase nano-precipitated steel was strengthened through a bowing mechanism through which unpinning occurred, dislocation loops were formed, and the microhardness of ferrite was increased. The development of an incipient cell structure in the ferrite matrix was caused by wavy dislocation. After the onset of fatigue, the grain was preferentially rotated toward the {101}α orientation. Higher strain amplitude or lower strain rate led to a more favorable degree of misorientation in the low-angle grain boundaries.

In recent years, with the rapid development of FTTH technology, along with the rapid application of information consumption and e-commerce, users' demand for network bandwidth is growing. Users not only pursue practicability, but also require that the opening of optical fiber into the home can be realized quickly. At the same time, the indoor buildings are damaged to the minimum, and the broadband optical cable and equipment in the living space need to be beautiful. In view of this problem, we put forward the overall solution of invisible optical cable. This paper mainly describes the structure, performance and application of several kinds of invisible optical cable. [ABSTRACT FROM AUTHOR]

In order to reveal the residual distribution pattern and obtain a wide range of high-accurate vertical movement field, we systematically analyzed the joint geodetic adjustment with vertical rate parameters (denoted as joint adjustment) issues based on the simulated and actual multi-source vertical data. First of all, 1000 sets of simulated leveling data containing rand noise were constructed and processed. The corresponding adjustment results show that network shape and observation interval are two main factors affecting the reliability of the vertical rates. Particularly, vertical rates of the small loops, internal points and loops with longer intervals are prior to those of large loops, edge points and loops with short intervals, respectively. Subsequently, we developed a Helmert adjustment program, which can jointly process leveling data and space geodetic data. Compared with the single leveling data adjustment (SLDA), the joint adjustment results of leveling data and 500 geodetic observations (including 2–4 mm/yr errors) demonstrate that the Helmert adjustment can reduce the residual distribution range by roughly 46%. Finally, both SLDA and Helmert methods are applied to actual survey data in eastern China. We find that the error of the latter approach is decreased by about 48% compared with the former. In summary, the Helmert adjustment method can significantly improve the reliability and accuracy of vertical movement in large area.

This dissertation investigates how multinational enterprises (MNEs) respond to host country political violence (specifically, terrorist attacks), and how factors influencing top management teams' (TMTs) decision making subsequently impact MNEs' responses. Across three essays, I found that MNEs' divestments, their likelihood of temporary vs. permanent divestment, and their likelihood of exerting information control in response to host country terrorist attacks are contingent upon executives' social proximity to the event host countries, CEO conservatism, and TMT gender diversity. This dissertation contributes to a more comprehensive understanding of the role of managerial interpretation in MNEs' responses to host country political violence. [ABSTRACT FROM AUTHOR]

Columns For Michael Reardon, the fun begins with pencil sketches, like this one for his painting San Stae (watercolor on paper, 20×10). Katherine Chang Liu's painting, Sanctuary (mixed media, 24×20) features imagery on the left that represents her studio "with even a painting table in the middle", she says. Imagine (watercolor and gouache on paper, 26×22) by Carla O'Connor James Toogood Identifying and solving the hundreds, perhaps thousands, of issues that arise while making a painting is exciting. [Extracted from the article]

The nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element signaling pathway plays a substantial role in preventing oxidative stress-related diseases. Aspirin has been shown to exert several pharmacological effects by inducing the expression of the heme oxygenase-1 (HO-1) protein. However, the effects of aspirin on spinal cord injury (SCI) have rarely been studied. Therefore, we sought to investigate the neuroprotective effects of aspirin after SCI. We employed a spinal cord contusion model in Sprague-Dawley rats, and aspirin was administered intraperitoneally for 7 days. Nissl staining showed that the aspirin treatment significantly reduced the loss of motor neurons after SCI compared with vehicle-treated animals. The expression of Nrf2, quinine oxidoreductase 1, and HO-1 proteins was increased in aspirin-treated animals after SCI compared with the vehicle group. In addition, aspirin simultaneously decreased the expression of inflammation-related proteins, such as tumor necrosis factor-α and interleukin-6 after SCI. Moreover, the ratio of apoptotic neurons in the anterior horn and the levels of the apoptosis-related proteins caspase-3, cleaved caspase-3, and Bax were significantly decreased in the aspirin group compared with the vehicle group. Immunofluorescence staining was used to detect the colocalization of NeuN and HO-1, and the results showed that aspirin significantly increased expression of the HO-1 protein in neurons. In addition, western blots and immunofluorescence staining showed aspirin restrained astrocyte activation. In conclusion, aspirin induces neuroprotective effects by inhibiting astrocyte activation and apoptosis after SCI through the activation of the Nrf2/HO-1 signaling pathway.

Conventional crude lead electro-refining based on fluosilicic acid (H2SiF6) system is suffering unwelcome environment burden due to the high volatility and instability of H2SiF6. Recycling secondary lead (Pb) resource resulted in high-content antimony (Sb) in the crude lead. Herein, we proposed a green, efficient and safe methanesulfonic acid (MSA) system for fluorine-free electro-refining process of Sb-rich crude Pb. Influencing mechanism of MSA concentration, additive content, Pb ion concentration, cathodic current density, solution temperature on morphology control and energy performance was investigated. Electro-refining simulation and verification in the MSA system achieved an energy consumption of 119.9 kWhe/t Pb and a current efficiency of 99.23%, which were competitive with 145 kWhe/t Pb and 97.99% in the H2SiF6system. The Pb purity of the deposit sample was as high as 99.99%. The MSA system had favorable Sb tolerance (4-5% Sb), which was higher than the H2SiF6system (≤0.8% Sb). Current research provided a technically- and economically-feasible solution for the electro-refining of crude lead with high Sb content.

The Tibetan Plateau is characterized by high elevation and complex fault systems. High‐precision vertical movement data can provide important constraints for understanding the growth and expansion of the Tibetan Plateau. We collected approximately 116,000 km of leveling data, 21 continuous GNSS data sets, and their connecting surveying data; we jointly processed these data using a Helmert joint adjustment method to acquire the high‐precision vertical velocity field of the Tibetan Plateau and its surrounding areas. The primary results are as follows: (a) Vertical uplift is dominant on the southern, northeastern, and southeastern margins of the plateau, with uplift rate ranges of 2.0–3.0, 1.0–3.8, and 1.0–2.0 mm/yr, respectively; (b) Conspicuous subsidence is located along the southern portion of the Ganzi fault, with vertical rates ranging from −3.3 to −0.5 mm/yr; (c) Velocity profiles show that vertical deformation varies in different parts of the Tibetan Plateau, which is mostly accommodated by large strike‐slip and thrust faults, such as the Kunlun, Ganzi, and Longmenshan faults. Most of the surface uplift is accommodated by crustal shortening in the interior of the Tibetan Plateau; abrupt changes in vertical rates in eastern Tibet and the widely distributed surface subsidence of southeastern Tibet are consequences of crustal flow and gravitational collapse. Overall, the Tibetan Plateau is characterized by continuous deformation, with large spatial variations accommodated by complicated tectonic processes. Research on the vertical deformation of the Tibetan Plateau lags behind that on horizontal deformation. Quantitative and high‐precision vertical movements are indispensable for resolving the geological diversity of the Tibetan Plateau. In this study, we systematically collected and processed approximately 116,000 km of leveling data from 1970 to 2017 and obtained high‐precision vertical rates (i.e., average error of 1.4 mm/yr). Through the analysis of detailed vertical movement characteristics, three‐dimensional deformation patterns, and velocity profiles, an entire overview and detailed features of the deformation distribution of the Tibetan Plateau are presented and analyzed. These high‐precision vertical movements provide a geodetic data set to study the kinematic growth and expansion of the Tibetan Plateau, India‐Eurasia continental collision, geomorphological evolution of the plateau, and interseismic deformation for strong earthquakes. Leveling data were jointly processed with continuous Global Navigation Satellite System data to obtain high‐precision vertical movements in the Tibetan PlateauUplift is dominant in the Tibetan Plateau, and the southern, northeastern, and southeastern margins are three significant uplift areasHigh‐precision 3D deformation data show harmonious features, indicating continuous deformation across most of the Tibetan Plateau Leveling data were jointly processed with continuous Global Navigation Satellite System data to obtain high‐precision vertical movements in the Tibetan Plateau Uplift is dominant in the Tibetan Plateau, and the southern, northeastern, and southeastern margins are three significant uplift areas High‐precision 3D deformation data show harmonious features, indicating continuous deformation across most of the Tibetan Plateau

Highly efficient Sr2Si5N8:Eu2+red emitting phosphor was successfully synthesized by a cost-effective direct silicon nitridation and gas-reduction method. The effects of synthesis parameters, including reaction temperature, heating rate and gas species, on the crystal structure and photoluminescence of the prepared phosphors were studied. Single-phase Sr2Si5N8:Eu2+phosphor was obtained at 1500 °C with a heating rate of 300 °C/h under NH3-1 vol.%CH4atmosphere using starting silicon and oxide powders. Silicon powder and high heating rate favored the achievement of the pure Sr2Si5N8phase. Under near-UV to blue light excitation, the obtained Sr2Si5N8:Eu2+phosphor showed a board red emission band centered at about 625 nm, which agreed well with the phosphors prepared by the conventional solid-state reaction. The possible reaction mechanism was also proposed based on the experimental observations.

Micro Multi-propeller Multifunction Aerial Robot (MMAR) needs a low-cost, small-size, low-power and lightweight navigation system. To meet these requirements, a compact navigation system for micro MMARs is designed and implemented. The system consists of a GPS receiver, a MEMS inertial measurement unit (IMU), a barometer, a magnetometer and a dual microprocessors navigation processing platform. According to the characteristics of the sensors used, the optimized Kalman Filter (KF) is designed to implement the navigation data fusion with less computational cost. The test results show that the system’s small size, low power consumption, light weight and better dynamic accuracy can meet the requirements of micro MMAR autonomous flight.

This article aims to study the influence of negative skin friction resistance of waterishlogged pile foundation, through indoor scale model test of pile foundation in the loess areas. The program involved in the model similar than design, the model groove design, the selection of test materials, the design of the ground soil, the layout of measuring points and the research of load method in the test. Through the experimental study on the reduced scale model, we can deepen the understanding of the action mechanism of negative skin friction resistance of the pile, which could guide the engineering practice and design.

The target of this paper is to research the change law of the negative friction for after soaking. The negative friction of pile group is measured through the indoor reduced scale model test in loess area. The similarity ratio design, the groove design of the model, the selection of test materials, the design of the ground soil, the layout of measuring point and the research of load method are involved in this test. Through the study on the reduced scale model, it will have a deeper understanding to the mechanism of pile side negative frictional resistance.It also can guide the design and practice of other engineering.

According to characteristics of the project characteristics, fault tree analysis method is adopted and fault tree model is established to decompose the reasons that affect the project schedule layer by layer. Taking a dam construction project as an example, according to the degree of structural order, various factors are explored to calculate the degree of influence of the delay in progress, and the corresponding measures are proposed to control the schedule.

AbstractWe report on the design and characterization of the plasma mirror system installed on the J-KAREN-P laser at the Kansai Photon Science Institute, National Institutes for Quantum Science and Technology. The reflectivity of the single plasma mirror system exceeded 80%. In addition, the temporal contrast was improved by two orders of magnitude at 1 ps before the main pulse. Furthermore, the laser near-field spatial distribution after the plasma mirror was kept constant at plasma mirror fluence of less than 100 kJ/cm2. We also present the results of investigating the difference and the fluctuation in energy, pulse width and pointing stability with and without the plasma mirror system.

The low strain method has the advantages of simple, fast detection is widely used in the pile testing. The low strain method was presented to pile test on a communication hinge engineering of China Mobile Group Gansu Co.,Ltd. The basic theory, tesing method of pile and judgment standard about the ultrasonic wave method are analyzed.

This study examined the effects of curcumin on the pharmacokinetic and pharmacodynamic properties of warfarin and clopidogrel in Wistar rats. Results showed that oral administration of curcumin at 25mg/kg, 50mg/kg, and 100mg/kg for 7 days had no substantial effects on the pharmacodynamics of warfarin and clopidogrel in this animal model. However, oral administration of 100mg/kg curcumin for 7 days significantly increased the AUC∞-8 and Cmax of the two drugs (by x 1.6 and x 1.5, respectively, for warfarin, and x 1.61 and x 1.81, respectively, for clopidogrel carboxylic acid). However, compared to warfarin alone, different doses of curcumin combined with warfarin had no effects on the prothrombin time in rats. Similarly, a combination of curcumin and clopidogrel had no significant effect on the maximum platelet aggregation rate of rats compared with the use of clopidogrel alone. This work demonstrated that preadministration of 100mg/kg curcumin affected the pharmacokinetics of warfarin and clopidogrel but had no effect on pharmacodynamic parameters such as anticoagulation rate and antiplatelet aggregation. [ABSTRACT FROM AUTHOR]

The international financial crisis on our economic development resulted in the inevitable impact on Chinese economy. In order to get rid of the impact, the expansion of domestic demand has been a crucial means of steady economic growth in China. However, the farmers over seven million account for a large proportion should be the main consumers in China. On the contrary, the current lack of domestic demand in China, which is mainly in rural consumption, is the lack of the critical issues of our efforts to expand domestic demand. This paper clarified the factors restricting China rural residents' consumption demand expansion, and on this basis explored the expansion of rural residents' consumption demand countermeasures. Empirical analysis was used to prove the low level of income of rural residents' constraints, and also to expose the fact that social security system was imperfect. Meanwhile, rural infrastructure restricted the consumption level of rural residents. The consumer market is an effective way to improve rural residents' consumption demand.

Metal Reinforced Polyethylene Spiral Pipe (MRPSCP) is an innovative product of underground sewer. This product is a combination of the high stiffness and strength of steel and the better flexible and corrosion resistance of polyethylene. This paper mainly discussed some production technology and the product quality control of MRPSCP.

The ultrasonic wave method was presented to pile test on the complex building engineering of China Mobile Group Gansu Co.,Ltd. The basic theory, tesing method of pile and judgment standard about the ultrasonic wave method are analyzed.

The low strain method has the advantages of simple, fast detection is widely used in the pile testing. The low strain method was presented to pile test on the complex building engineering of China Mobile Group Gansu Co.,Ltd. The basic theory, tesing method of pile and judgment standard about the ultrasonic wave method are analyzed.

Navigation and hydropower junction is a new model of inland river development. Such projects have significant economic, social and environmental benefits, and the corresponding indexes are quantitative and qualitative. Therefore the post-evaluation is a complex and multi-targeted semi-structural problem. The fuzzy set theory is applied on the comprehensive post-evaluation of navigation and hydropower junction of inland river. The recognition model based on multi-level fuzzy pattern and the semi-structured evaluation model are adopted. The evaluation is intuitive and comprehensive by combining the objective and quantitative assessments and the experience of the appraisers. And an example of Xiang River is given to illustrate its feasibility and rationality.

The explicit dynamic finite element theory is applied on the collision of ships with buoys for computer simulation. Using ANSYS/LS-DYNA finite element analysis software, the numerical simulation of the collision between the ton ship and the buoy with different structures and impact points. The collision force, deformation, displacement parameters and the weak impact points of a buoy are obtained. Based on the numerical simulation results, analysis of buoys and structural collision damages in anti-collision features are discussed, and several theoretical sugestions in anti-collision for the design of buoy are provided.

The experiment focused on the contrast with rock breaking effect of impacting water jet by modulation of chaos and common cavitation jet. Investigated the influences of various water jet parameters and conditions on rock breaking, such as standoff distance, pump pressure, transverse speed and erosion time and the mass loss and erosion depth were measured in the experiment. The results show that the impacting water jet by modulation of chaos can efficiently use the energy of water jet and increase ability in rock-breaking, which will have a wide application prospect in high pressure water jet technology field.

In this paper, the ultrasonic vibration uniaxial tension experiment was carried out on the 20# steel with a set of ultra-high-frequency vibration device. It showed that the material defect was the important factors of ultrasonic “soften” mechanism and obtained the crack extension mechanism under ultrasonic fatigue loading, there were：(1)The high frequency vibration of the ultrasonic fatigue loading weakened the influence of the plastic zone of the crack tip and residual stress on crack extension; (2)When the fatigue crack extension, the ultrasonic wave spread in the specimen, and reflected in the crack surface, resulting the crack closure effect decreased, the plastic zone of the crack tip decreasing; (3)The high vibration frequency and deformation velocity resulted the increase of the thermal effect, crack extension energy spread to the continuous medium in the form of heat, promoting crack extension and releasing energy. It also study the influence of different groove depth and groove curvature on the material ultrasound fatigue limit, and obtained the relation curve of fatigue limit with groove depth and groove curvature.

We generate narrow-band frequency-tunable entangled photon pairs from spontaneous four-wave mixing in three-level cold atoms and study their two-photon quantum interference after a beam splitter. We find that the path-exchange symmetry plays a more important role in the Hong-Ou-Mandel interference than the temporal or frequency indistinguishability, and observe coalescence interference for both degenerate and nondegenerate photons. We also observe a quantum beat in the same experimental setup using either slow or fast detectors. [ABSTRACT FROM AUTHOR]

The effect of molding temperature, pressure, packing time and cooling methods on the properties of ramie roving reinforced polypropylene composites was mainly investigated in this paper. We used moulding process to prepare the ramie fiber/PP (Polypropylene) composites with the ramie roving as the reinforcement which were loosed into a single fiber state in the case of without affecting the fiber’s longitudinal straightness, and then investigated the influence of processing conditions to the mechanical properties of composites. With the DSC (Differential Scanning Calorimetry), the effect of cooling conditions on the crystallization of composites was also discussed. The result shows that taking ramie roving as the reinforcement will improve the infiltration properties of the PP matrix to ramie fibers, the reason is that ramie fibers have good orientation and it is loosely arranged in the ramie roving , all of these are benefit to form a good interfacial bonding between fibre and PP resin. Different processing conditions have great impact on the mechanical properties of composites. And the samples gained the best merchanical properties when the process conditions such as molding temperature, pressure, packing time are selected as 165℃, 8MPa, 10min. When the composites cooled together with the heating plate, its melting enthalpy is the highest and the crystallization properties is better than other cooling methods such as home temperature cooling and quickly water-cooling, and its tensile properties is the best.

This study presents the development of a finite element model with the capability to simulate and analyse the response of steel bolted beam-column connections subjected to rapid rate of applied loading. The effect of material strain-rate sensitivity was taken into account and a shear failure criterion was adopted to predict the failure of the connection. By comparing the simulation results with the experimental observed responses, it is found that the numerical techniques and the material model used here can predict the structural behaviour of connections reasonably well.

OBJECTIVE To analyze transforming growth factor β–induced (TGFBI) gene mutations in 2 Chinese families with Thiel-Behnke corneal dystrophy (TBCD). METHODS Forty-five individuals in 2 Chinese families with TBCD were examined using slitlamp biomicroscopy. Genomic DNA was extracted from peripheral leukocytes of affected and unaffected family members. Molecular genetic analysis of the TGFBIgene was performed using polymerase chain reaction and standard automated sequencing methods. RESULTS In 17 family members with TBCD, an Arg124Cys (R124C) mutation of the TGFBIgene was identified, whereas the Arg555Gln (R555Q) mutation was absent. The Arg124Cys mutation was absent in all unaffected individuals. CONCLUSIONS The Arg124Cys mutation was associated with TBCD in 2 Chinese families. This mutation in the TGFBIgene may induce different phenotypes of corneal dystrophy. CLINICAL RELEVANCE Thiel-Behnke corneal dystrophy may be caused by an Arg124Cys mutation of the TGFBIgene.Arch Ophthalmol. 2009;127(5):641-644--

The debonding of a rigid particle embedded in an infinite non-linear viscoelastic material is investigated in this paper. Under sphere-symmetric deformation, a non-linear equilibrium equation expressed by velocity of a particle in the viscoelastic matrix material is derived. The strain rate is obtained by solving non-linear equation in terms of iterative method. According to the energy criterion, the critical instant of the interfacial debongding is calculated. Numerical results show that the influence of non-linear viscosity on the interfacial debonding is significant.

In the present study a modified CFD code KIVA3V was used to simulate the spray combustion in a small DI diesel engine fueled with DME. The improved spray models consider more spray phenomena such as cavitation flow in nozzle hole, jet atomization, droplet second breakup and spray wall interaction. Otherwise, a reduced DME reaction mechanism is implemented in the combustion model, and a new turbulent combustion model-Partial Stirred Reactor (PaSR) model is selected to simulate the spray combustion process, the effects of turbulent mixing on the reaction rate are considered. The results of engine modeling based on those models agreed well with the experimental measurements. Study of temperature fields variation and particle traces in the combustion chamber revealed that the engine combustion system originally used for diesel fuel must be optimized for DME.

The 921 Chi-Chi earthquake caused a very significant number of building collapses and damage of various degrees. Many collapsed buildings had pedestrian corridors and open fronts on the ground floors. Using a modified modal participation factor and the generalized shape function computed from the nonlinear push over analysis, story drift demands imposed on soft first story building systems are studied in this paper. Generalized shape functions are constructed from the nonlinear static push over analysis of shear buildings having specific distributions of story stiffness and strength. Nonlinear response spectrum analyses were performed on the ground acceleration recorded from 51 sites located in the Taipei Basin and 62 sites in the Taichung Region. Analytical results indicate that soft first story buildings are likely to have story drift demands significantly greater than regular buildings of short fundamental period. Results of the nonlinear dynamic analysis of a 6-story structure indicate that the maximum story drift demand can be satisfactorily predicted by the story spectral drift constructed from the generalized shape functions.

Mathematical models for the effects of the calcination process conditions on the mechanical properties of a PCoMo / Al 2 O 3 hydrotreating catalyst are developed using a response surface methodology. A central composite design is performed to study collectively the effects of calcination temperature, calcination time and heating rate on the mean strength and Weibull's modulus. A model is obtained for each response with multiple regression analysis and then is refined. Analysis of variance reveals that the models developed are adequate. The validity of the models is also verified by experimental data. Statistics reveals that there is a great potential for increasing the mechanical reliability in the calcination process. Analysis of response surface show that the mean strength and Weibull's modulus increase with the increase of calcination temperature. The middle level of heating rate results in smaller mean strength and higher Weibull's modulus. The mean strength increases as calcination time increases. However, calcination time has no significant effect on Weibull's modulus in the experimental domain examined.

We study the magnetization of gapped spin 1/2 XXZ Heisenberg Ising chains and calculate the scattering length among massive spinons. We obtain the magnetization close to the critical external magnetic field. The leading correction term determined by the scattering length among massive spinons is given. Our results are in agreement with exact results and with experimental results. We show that the deviation from the massive free hard core boson picture can be accounted very well by the leading correction term due to the spinon-spinon interaction. We show that the deviation increases along with the increasing of the Ising term.