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Stem photosynthesis (荒漠植物长期演化过程中保留了枝干光合(

Rhabdomyoma is a rare benign soft tissue tumor deriving from striated muscle. It can be classified generally into two subtypes according to the location: cardiac rhabdomyoma and extracardiac rhabdomyoma. Cardiac rhabdomyoma manifests as well-defined solitary or multifocal nodules in heart consisting myocardial-like tumor cells with rich cytoplasm, which is more common in kids and associated with tuberous sclerosis (1). Extracardiac rhabdomyoma can be divided into three groups according to morphological features (adult, fetal, and genital types). The adult and fetal types mainly occur in the head and neck region, while the genital type usually occurs in the genital tract. To the best of our knowledge, rhabdomyoma is rarely found in the respiratory system and the visceral pleura. Only one case of pulmonary rhabdomyoma has been reported in the English literature (2). It is difficult to make a correct pre-operative diagnosis. Herein, we report the first case of rhabdomyoma originating from visceral pleura.

Spatial variation is a ubiquitous feature of natural ecosystems, especially in arid regions, and is often present at various scales in these regions. To determine the scale dependence of the heterogeneity of soil chemical properties and the dominant scales (factors) for soil heterogeneity in arid regions, the spatial variability of soil resources was investigated in the Gurbantunggut Desert of Central Asia at the scales of 10 −3 , 10 −2 , 10 −1 , 10 0 , 10 1 , 10 2 , 10 3 and 10 4 m (from individual plant to population or community to ecosystem). Soil chemical properties including pH, electrical conductivity (EC), organic carbon, total nitrogen, available nitrogen, total phosphorus, and available phosphorus were considered in the investigation. At a scale of 10 −1 m, which represented the scale of individual plant, significant enrichment of soil resources occurred under shrub canopy and “fertile islands” formed in the desert ecosystem. Soil EC exhibited the largest heterogeneity at this scale, indicating that individual plants exerted a great influence on soil salinity/alkalinity. Soil nutrients exhibited the greatest heterogeneity at a scale of 10 2 m, which represented the scale of sand dune/interdune lowlands (between communities). The main important factors contributing to soil spatial heterogeneity in the Gurbantunggut Desert were individual plants and different topographic characteristics, namely, the appearance of vegetation, especially shrubs or small trees, and existing sand dunes. Soil salinity/alkalinity and soil nutrient status behaved differently in spatial heterogeneity, with an inverse distribution between them at the individual scale.

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Modal analysis of driving system and telescopic mechanism of bar on two wheels scooter is investigated. The first five orders natural frequency and major modes of driving system and telescopic mechanism of bar are clarified. The method and the result can be used as a reference of dynamic design and lay foundation for calculation and analysis of dynamic response for the two wheels scooter.

Packet loss is unavoidable in IP multicast using the UDP protocol that will serious influence video quality. In this paper we use the Raptor codes for video multicast to improve the video quality. Firstly, the principle of Raptor codes is analyzed in detail. Then the Raptor codes is implemented and transplanted in the video transmission system. Simulation results show that the video transmission system with Raptor FEC works which can overcome the packet loss effectively and improve the playback quality significantly.

Kinematic characteristics of double-rocker mechanism is analyzed. Based on variable ratio transmission characteristics of elliptical gear, elliptical geared double-rocker mechanism is presented. Kinematic characteristics of elliptical geared double-rocker mechanism is clarified. Eccentricity is optimized. The elliptical geared double-rocker mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

The construction with hanging basket eccentric loading was studied for the cantilever casting of a 32m +48 m +32 m continuous box girder. The calculation of center deflecting angles of cantilever box girders with variable cross-section due to pure torsion was derived, and correspondingly a program was developed to calculate this formula. An analysis model of cantilever casting continuous beam bridge with hanging basket eccentric loading was established based on finite elements software, and the shear stress, the longitudinal normal stress and the combined stress of different section were analyzed under different construction process. The torsional effect due to hanging basket eccentric loading was studied and the results are helpful to guide the construction in practice.

Refining performance and mechanism of Al-5Ti-1B and Al-5Ti-0.4C master alloys at different temperature were investigated in this paper. The experimental results show that the refining effect of Al-5Ti-0.4C master alloy becomes worse as temperature increasing from 750°C to 1200°C, The refining effect of Al-5Ti-1B master alloy becomes worse as temperature increasing from 750°C to 1000°C. However, when the temperature is above 1000°C, the refining effect of Al-5Ti-1B master alloy recovers gradually as temperature increasing. TiB2 particles with TiAl3 layers are the heterogeneous nucleating cores of α-Al at low temperature. However, TiB2 particles are the heterogeneous nuclei of α-Al at high temperature.

A two-dimensional electromechanical analysis is performed on a transversely isotropic piezoelectric material containing a line crack of length 2a, which is subjected to uniform distributed forces with intensity q along the crack faces and uniform electric displacement fields at infinity. Based on the impermeable electric boundary conditions, the closed complex form expression for the electromechanical fields are deduced in the vicinity of the crack. Taking PZT-4 ceramic into consideration, electromechanical fields under different loads are illustrated through several examples. It can be seen that electromechanical fields show 1/2 order singularity at the crack tip, and the piezoelectric effect can’t be negelected.

At present, the objective of cutting and pruning Cistanche deserticola is to harvest in successive years and enhance the harvesting yield and quality of C. deserticola in the process of the artificial cultivating C. deserticola. An experiment was conducted focusing on cutting and pruning C. deserticola in artificial forests of Haloxylon ammodendron drip-irrigated with saline water at the hinter-land of the Taklimakan desert, according to different growth stages and lengths. The results were following: (1) The effect of cutting on C. deserticola was similar to that of pruning, which resulted in three kinds of morphological types, not related to the bloom and size of C. deserticola. (2) The growth forms were diversified after pruning. Among them, there had sprouting new body, died or maintaining life with no sprouting, mildewed on its surface layer, etc. However, some of new bodies were sprouting from the lower part of the old body. The death rate of bloomed C. deserticola was higher than that of the underground, and the death rate of the 40 cm in stubble height for C. deserticola was higher than those with the stubble height of 20 cm and 5 cm. (3) Most of the diameter of living C. deserticola after pruning was increasing, but some of them changed little. (4) The mildew and rot of C. deserticola and the broken of the roots of the H. ammodendron and the fallen of the point of the inoculated when it was dug, which would cause the death of the C. deserticola. On the other, the yield-increasing effect and the economic benefit of the techniques of the pruning of Cistanche would need further research and evaluate. Therefore, the application of this technique needs to be cautious.

Rhizama Chuanxiong is a kind of traditional medicinal herb used to promote blood circulation and eliminate wind to relieve pain. In this work, nano Rhizoma Chuanxiong particles were successfully prepared by high speed centrifugal sheering (HSCS) pulverizer. The influence of processing parameters on the size of Rhizama Chuanxiong particles and the different properties between nano Rhizoma Chuanxiong particles and original fine powder were systematically studied by ZetaPALS light scattering granulometric analyzer and optical microscope. The content of effective ingredient tetramethylpyrazine (TMP) was determined by high-performance liquid chromatography (HPLC). The results illustrate that general Rhizama Chuanxiong powder can be ultrafinely ground to nanometer within 50 min, and the cellular tissues of Rhizoma Chuanxiong are broken into pieces and dispersed stably and homogeneously after being ultrafinely ground. In addition, the active ingredients can dissolve out directly and fully, and the extraction ratio of TMP is increased 32.2% by HSCS processing.

This paper analyzes the problems existing in design and manufacture of the reciprocating screw in the spooling gear and proposes the solutions accordingly. By adopting software such as Solidworks and Unigraphics for three-dimensional design, a solid model meeting the design requirement can be obtained, providing good reference value for design and manufacture of the screw.

From the bus active safety standpoint, this article designs the embedded system to control the speed of automobile in time without changing the original structure. The system selects STR712FR2 based on ARM7 as the microprocessor, able to control the automobile speed in accordance with the road conditions. The system has advantages in simple structure, low power consumption and practical function. The system function, the overall design and implementation procedure of the system, the software and hardware choice are analyzed in detail. Meanwhile, the initial validation of the system is carried out.