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All-inorganic cesium lead bromide demonstrates better thermal and chemical stability compared to its hybrid counterparts, and thus it can provide a base for high stability and performance of CsPbBr3-based perovskite light emitting diodes (PeLEDs). Appropriate cation doping engineering could further improve the stability and performance of CsPbBr3 films and PeLED devices. Here, the stability and luminescence performances of B-site and A-site cation doped CsPbBr3 films and PeLEDs are summarized and critically compared. The mechanisms of the improved properties after doping are discussed. In addition, a conventional analysis of lattice parameters in terms of spontaneous strains is provided for the first time for CsPbBr3 perovskites, in which they have robust correlations with the stability of the CsPbBr3-based films and PeLEDs. Meanwhile, the cation doping process is an effective method to flexibly modulate the spontaneous strains to enhance the stability and luminescence properties of the metal halide perovskites and PeLEDs. Doping and strain engineering in the field of perovskite optoelectronics will certainly encourage very important future developments in materials science, physics and chemistry for operationally stable PeLEDs.

In this study, we designed a novel magnetic semiconductor Sr2FeMoO6/SrMoO4 with a sharp metal-insulator transition based on the spin-glass freezing and antiferromagnetic transition behavior, which has been confirmed by various magnetic and transport measurements. To investigate the charge transport mechanisms of the sample, the electrical resistivities have been measured over a wide range of temperatures from 400 K down to liquid helium temperatures under different magnetic fields. The typical semiconductor behavior of the sample is observed. The relatively high conduction behavior is blocked below 80 K, and thereafter into the insulator state. The Vogel-Fulcher and the Mott variable-range-hopping (VRH) law are also used to study its conduction features and the relationship between magnetic and electrical properties. The spin-glass like component around the Sr2FeMoO6 crystal is initially observed by TEM and this provides a robust evidence able to verify the results from magnetic measurements. The novel features of the metal-insulator transition shielding external magnetic effects in highly disordered Sr2FeMoO6 double perovskite is dominantly controlled by a new spin-valve-system present in the spin-glass layers. Our insights into the role of the B-site disorder, spin-glass layer around the soft ferromagnetic grains, grain boundaries, and non-magnetic second phase effects demonstrate how the static and dynamic properties of magnetic materials might be tuned by designing the composition with a high B-site cation disordered matrix ferromagnetic material.

The epithelial and epidermal innate cytokines IL-25, IL-33, and thymic stromal lymphopoietin (TSLP) have pivotal roles in the initiation of allergic inflammation in asthma and atopic dermatitis (AD). However, the mechanism by which the expression of these innate cytokines is regulated remains unclear. Intelectin (ITLN) is expressed in airway epithelial cells and promotes allergic airway inflammation. We hypothesized that ITLN is required for allergen-induced IL-25, IL-33, and TSLP expression. In two asthma models, Itln knockdown reduced allergen-induced increases in Il-25, Il-33, and Tslp and development of type 2 response, eosinophilic inflammation, mucus overproduction, and airway hyperresponsiveness. Itln knockdown also inhibited house dust mite (HDM)-induced early upregulation of Il-25, Il-33, and Tslp in a model solely inducing airway sensitization. Using human airway epithelial cells, we demonstrated that HDM-induced increases in ITLN led to phosphorylation of epidermal growth factor receptor and extracellular-signal regulated kinase, which were required for induction of IL-25, IL-33, and TSLP expression. In two AD models, Itln knockdown suppressed expression of Il-33, Tslp, and Th2 cytokines and eosinophilic inflammation. In humans, ITLN1 expression was significantly increased in asthmatic airways and in lesional skin of AD. We conclude that ITLN contributes to allergen-induced Il-25, Il-33, and Tslp expression in asthma and AD.

Historic districts are a special type of cultural heritage, as living cultural heritage, the utilization and development of historical districts is an inevitable issue. How to accurately position the protection and utilization of districts and achieve its healthy and sustainable development is the key work in the protection of districts. In this paper, the Internet data including Tencent’s location big data are employed to study some Chinese historic and cultural streets, establish protection and development index system for historic and cultural streets, carry out in-depth study of ten core indicators, and sum up the positioning and development direction for the protection and use of districts. Historic district, as a special type of cultural heritage, is the birthplace and supporting zone of urban context, and also the place for the daily life of the general public. It boasts profound historic and humanistic background and the characteristics of a living form. As the living cultural heritage, its use and development are necessary, and attention shall also be paid to static protection and dynamic comprehensive management. But judging from the current practice, protection and use of historic districts face a host of challenges. Some districts are devoid of popularity and vitality and become cold galleries. Some districts suffer excessive development for tourism and commercialism, and lose its “original” cultural characteristics. In addition, throngs of tourists exert a negative impact on the life of the local people and the protection of immovable cultural relics. Disorderly business format and increasingly similar landscape go against the presentation of local characteristics. We should regard historic district as a dynamic urban heritage, and achieve dynamic development and protection in accordance with its inherent development laws and the principle of “step by step” through the “organic update” mode, with emphasis on the continuous comprehensive management of material space environment and cultural society. Therefore, how to make accurate positioning of the protection and utilization of districts and achieve its healthy and sustainable development is the key work in the protection of districts.

In China historical and cultural heritage resources include historically and culturally famous cities, towns, villages, blocks, immovable cultural relics and the scenic spots with cultural connotation. The spatial distribution laws of these resources are always directly connected to the regional physical geography, historical development and historical traffic geography and have high research values. Meanwhile, the exhibition and use of these resources are greatly influenced by traffic and tourism and other plans at the provincial level, and it is of great realistic significance to offer proposals on traffic and so on that are beneficial to the exhibition of heritage resources based on the research of province distribution laws. This paper takes the spatial analysis of Geographic Information System (GIS) as the basic technological means and all historical and cultural resources in China’s Zhejiang Province as research objects, and finds out in the space the accumulation areas and accumulation belts of Zhejiang Province’s historic cities and cultural resources through overlay analysis and density analysis, etc. It then discusses the reasons of the formation of these accumulation areas and accumulation belts by combining with the analysis of physical geography and historical geography and so on, and in the end, linking the tourism planning and traffic planning at the provincial level, it provides suggestions on the exhibition and use of accumulation areas and accumulation belts of historic cities and cultural resources.

The live load distribution-factor (LLDF) equations in the AASHTO-LRFD specifications were developed under National Cooperative Highway Research Program (NCHRP) Project 12-26. These equations include limited ranges of applicability, and when these ranges are exceeded, a refined analysis must be used. Additionally, the multiple-presence factors, bias, and variability with respect to the rigorous estimates are obscurely embedded. Herein, a simplified LLDF framework is provided. The effects of analysis uncertainty, variability, and multiple presence are separated and distinctly defined. This separation provides specification writers with the opportunity to use different multiple-presence and variability models. LLDFs were calculated using several simplified methods and grillage analyses for over 1,500 bridges. Based on the comparison, two simplified methods were further studied: adjusted uniform distribution and adjusted lever rule methods. Calibration factors were used to their improve accuracy. Seventy-four...

In future anti-tank combat, a higher requirement was presented due to the complexity of the battlefield environment and advanced technology of hostile armored forces. Commanders must solve the problems such as the rational allocation of existing anti-tank firepower according to the insult strength and battlefield environment, and the target allocation decisions in the course of combat. Both anti-tank combat and anti air raids process has the characters of the service process and can be described with queuing theory. Recently, many scholars studied the application of queuing theory in military systems such as anti-tank combat, air defense system operational process and the ship's air defense system, and accomplished some fruitful works [1-4]. However, these models did not consider the change of the service system in the course of combat caused by counterwork, and did not adjust the operational capability of the new system. Based on stochastic process theory and anti-tank combat theory, the combat effectiveness model compatible with the anti-tank combat process was established. Based on the model, the operational effectiveness of the combat scenario in which the vehicle-mounted anti-tank missiles and wheeled anti-tank assault guns construct the anti-tank defense system was computed, furthermore, weapon lose and other parameters with the troops and configuration changes was studied also.

The Fe-doped CuO nanopowders (Cu0.95Fe0.05O) were prepared by the sol–gel and the co-precipitation methods. The effects of synthesis methods on the structure, magnetic property and exchange bias effect of Cu0.95Fe0.05O nanopowders were investigated. The microstructure and magnetic properties of the two types of nanopowders were characterized by X-ray diffraction and physics property measuring systems, respectively. It was found that the sol–gel method tended to lead the formation of CuFe2O4 phase, which dominated the magnetic behaviors of the sample; the co-precipitation tended to lead larger exchange bias field at low temperature in samples, comparing with sol–gel method.

To evaluate high-density source and receiver land seismic acquisition designs, two sets of simultaneous highproductivity vibroseis field tests were performed in a relatively flat terrain area with good signal-to-noise ratio. These included distance separated simultaneous sweeping (DSSS) (Bouska, 2009), slip-sweep (Rozemond, 1996), distance separated simultaneous slip-sweep (dynamic slipsweep) and independent simultaneous sources (ISS) (Howe et al., 2008) with unique sweeps. The second dynamic slipsweep field test used a 29 km active fixed super-spread (12 receiver lines separated by 300 m) with 20 point vibrator fleets on a 25 m x 25 m source grid. A group of 10 point vibrators were oriented orthogonal to the receiver spread in the North and 10 in the South direction with a lateral separation distance of 14.5 km. This method achieved 30,346 vibrator points (VPs) in a 24 hour period. The same fixed active receiver spread was reduced to continuously record two unconstrained simultaneous sources (microseismic mode) in 18 sectors (3x6). Each sector was 1.8 km x 1.8 km with 4,320 VPs on a 25 m x 25 m source grid (77,760 total VPs) with 18 unique 12 s pseudorandom sweeps (Sallas et al., 2008) and repeated with 18 unique linear upsweeps (14.5 s average sweep length) from 5 to 110 Hz. We achieved optimum productivity rates of 45,501 and 44,793 VPs per 24 hours, respectively, with real-time quality control (QC) – we were not sweeping blind. Seventy two drivers were organized in three eight-hour shifts along with four vibrator pushers per shift. Three helped with fleet management and one for TDMA real-time communication between the vibrators and the recorder. Even higher productivity rates could have been achieved with stakeless guidance training of the vibrator drivers and pushers.

XLPE cables are widely used in urban distribution systems because of their excellent mechanical, heat and electrical properties. However, water tree, formed due to the existence of water and intense electric field, is one of the primary causes of aging breakdown. There used to be several methods, such as insulation impedance method and DC leakage current method for the detection of bridged water tree, which are non-effective for the diagnosis of non-bridged one. Residual Charge Method is known for its effectiveness in the diagnosis of non-bridged one. In this paper, pulse voltage is applied to the DC voltage charged XLPE cable after grounding. It is called ‘Pulsed-type Residual Charge Method’ which is found to be more effective for the diagnosis of non-bridged water tree. The effects of DC voltage, grounding time and pulse voltage on the amount of residual charge are studied. Also, the releasing mechanism of residual charge by pulse is discussed. Accumulated results show that the improved method has a high resolution for the diagnosis of water tree degradation degree.

Musclin is a muscle-derived secretory peptide that induces insulin resistance in vitro. We studied the effect of musclin (0.5 microg/ml) on insulin-stimulated glucose uptake in rat skeletal muscles and also the effect of rosiglitazone (0.4 microg/ml). Preincubation of muscles with musclin resulted in decreased insulin-stimulated glucose uptake. Musclin also reduced expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and liver X receptor alpha (LXRalpha) mRNAs, although expression of glucose transporter 4 mRNA was unaltered. Rosiglitazone attenuated the effects of musclin on glucose uptake and PPARgamma and LXRalpha mRNA expression. Western blotting demonstrated that activation of protein kinase B (Akt/PKB) in the insulin-signalling cascade was decreased by musclin but corrected by rosiglitazone. These findings suggest that musclin-induced impairment of insulin-stimulated glucose uptake in skeletal muscle is related to Akt/PKB inhibition and might be modulated by PPARgamma/LXRalpha.

Beamlets are combined with zero-tree coding algorithm to create a new coding method, particularly suitable for lines and curves. Beamlets are a multiscale collection of line segments at a range of scales, location, having a variety of lengths and orientations. The new coding scheme - named JBEAM is more efficient - in terms of bit rates - in coding binary curvy images in simulations.

Tibet II Air Shower Array consisting of scintillation counters with lattice of 15 m spacing has been operated with very high trigger rate of about 200 Hz. The threshold enegy of this array is estimated to be about 8 TeV for proton induced showers. Tibet High Density (HD) Array with 7.5 m spacing has been operated with the trigger rate of 115 Hz. The Mode energy of this array is estimated to be about 3 TeV for proton showers. Angular resolution of the arrays are estimated to be 0.9 degree above 10 TeV for Tibet II array, and 0.85 degree above TeV for HD array, resepectively. The angular resolution of these arrays and other array performances are examined by observing the Moon shadow resulting from the cosmic ray deficit in the direction of the Moon. Using the deflection of the Moon shadow to the east-west direction, the error of the array can be estimated by observing the displacement of the shadow in the north-south direction, because it is free from the effect of geomagnetic field, especially at Yangbajing in Tibet. The calibrations such as primary energy, angular resolution and pointing errors, directly using the Moon shadow has first been done by the Tibet experiment.

The Tibet ASγ experiment, which has started since January, 1990, is located at an altitude of 4,300m at Yangbaging in Tibet, China (90.5° E, 301° N). The air‐shower array is composed of 49 scintillation counters for fast timing (FT), each counter having an area of 0.5 m2, in a grid pattern with a spacing of 15 m and 16 density detectors. The density detectors surrounding the FT detectors are planned to select the showers of which core are inside the FT array. For the constant and continuous opeation, the system for laser calibration, the ADC,TDC module calibration and the power check system were installed. A Rb clock is used for the phase analysis of γ‐rays.The array is usually operated by the trigger rate of ∼20Hz with any 4‐fold coincidence of the FT detectors. The analysis of experimental data shows that the performance of array is realized as expected by the Monte Carlo simulation. For the events of which core are inside the FT array, are obtained the following results. The detection threshold energy for γ‐rays is ∼40 TeV; the peak energy 20 TeV. The angular resolution around 100 TeV is ∼0.5°. The systematic error of arrival direction is considerably smaller than the angular resolution in the concerned energy region.