Search

The fur color of mammals is mainly determined by melanin synthesized by melanocytes. Cell staining includes melanocyte development, melanin synthesis and metabolism, and signal pathways regulating melanin synthesis. Melanocytes can be classified into many types, and these types can be identified by a variety of melanocyte markers. Fur color can judge the physical condition and nutritional status of animals, and different fur colors may have certain influence on animal production. This paper reviews the structural basis and development cycle of mammalian fur color formation, describes the cytochrome process from neural crest to mature melanocytes residing in several tissues, summarizes the types of melanocytes and the markers of each type of melanocytes, and discusses the application of animal coat color in animal production, providing help for analyzing the genetic mechanism of mammalian fur color formation and providing effective suggestions for animal production affected by fur color. [ABSTRACT FROM AUTHOR]

The tomato variety 'Micro Tom' is used as an experimental material in a fully artificial light-type plant factory. An LED light with adjustable illumination modes was used as the light source and a pure white LED light was used as the control. Different illumination mode, such as pure red light, pure blue light, mixed red and blue light, and alternating red and blue light were used as supplementary light. The influence of different red and blue supplemental lighting modes on the growth, development, and fluorescence characteristics of greenhouse tomatoes was explored. The results showed that: (1) in all treatments, the growth indicators and fruit weight of the tomato plants increased to a certain extent. The dynamic change of chlorophyll fluorescence was significantly affected by supplementary light. Pure red light supplementation had the greatest effect on the increase in plant height, stem thickness, leaf area, and yield of the tomato plants. Alternating red and blue light supplementation at intervals of 1h or 6h significantly promoted the increase in chlorophyll content and the improvement of PSII photosynthetic performance. (2) During the vegetative growth stage of tomatoes, under pure red light supplementation, the relative growth rate and absolute growth rate of plant height increased by 106.8% and 60% respectively compared to the control. The relative growth rate and absolute growth rate of stem thickness increased by 50% and 80% respectively. 44 days after sowing, the leaf area of the tomato plants under pure red light supplementation increased by 92.1% compared to the control.(3) During the reproductive growth period of tomatoes, compared with the control, 83 days after sowing, the number of fruits set under pure red light supplementation increased by 73.6%. The horizontal and vertical diameters and volume of tomato fruit increased by 34.4%, 35.3%, and 129.6% respectively.(4) Compared with the control, 44 days after sowing, the chlorophyll content in tomato leaves under alternating red and blue light supplementation at intervals of 1h or 6h increased by 30.3% and 31.8% respectively. 83 days after sowing, the performance index (PIABS) of tomato plants after alternating red and blue light supplementation at intervals of 1h or 6h increased by 100% and 30% respectively compared to the control. The electron transfer efficiency (ETo/CS) of PSII after alternating red and blue light supplementation at intervals of 1h or 6h increased by 16% and 23% respectively compared to the control. In summary, pure red light supplementation can effectively promote the growth and development of facility tomatoes. Alternating red and blue light supplementation at intervals of 1h or 6h significantly affects the fluorescence characteristics of tomatoes. In the future, the most suitable supplementary lighting mode can be chosen based on different production objectives. [ABSTRACT FROM AUTHOR]

Do jumps happen in the Chinese stock market when major events occur? What are the feature of these jumps? In this article, we adopted dynamic Jump-Garch model and analysize conditional mean, conditional variance, intensity and amplitude changes of jump. The result shows that jump intensity and amplitude of political events is greatest, together with weak hysteresis quality and endurance; natural disaster perform contrarily; economic events are placed in the middle. [ABSTRACT FROM AUTHOR]

Harvest 74-560 RZ F1" tomato was cultivated in a plant factory with LEDs. One of the four reproductive stages (flowering stage, expanding stage, color turning stage and harvesting stage) was subjected to low light intensity of 160μmol·m-2·s-1, while the other three stages maintained 1000 μmol·m-2·s-1. The light intensity kept 1000μmol·m-2·s-1 at all the reproductive stages in the control. The growth and fruit quality indices were measured to evaluate the effects of low light on tomato. The results showed that: (1) low light significantly affected the morphology of tomato plants at the flowering stage and expanding stage. Low light at flowering stage resulted in the most prominent overgrowth trend of tomato plants, as well as the least average number of leaves and nodes per plant which respectively decreased by 3.5 and 1.6 compared with the control. Low light at the expansion stage significantly reduced the content of carotenoid and the value of Chla/b compared with the control. The number of fruit set per plant after low light treatment at flowering stage was 53% lower than that of the control, while the number of fruit set per plant was not significantly affected by low light at other reproductive stages. The average yield of the first, second and third ear per plant after low light treatment at flowering or expansion stage was significantly lower than the other treatments. (2) Compared with the control, low light treatments decreased the soluble solid content of tomato fruit (first ear) in varying degrees, among which, the soluble solid content decreased by 25% after low light treatment at flowering stage. The soluble sugar content of tomato fruit decreased by 15% compared with the control, on the contrary, the total acid content increased by 26%, resulting in the lowest sugar/acid ratio of tomato fruit under this treatment. Compared with the control, low light treatments decreased the vitamin C content of tomato fruit in varying degrees, among which, the lowest vitamin C content was detected in tomato fruit subjected to low light treatment at the harvesting stage. This study showed that low light reduced the yield and quality of tomato, and the sensitivity of tomato to low light was different at varied reproductive stages. According to the growth characteristics and responses of tomato subjected to low light at different periods, it is of certain significance to supplement artificial light in order to stabilize the quality and yield of protected tomato. [ABSTRACT FROM AUTHOR]

A data fusion algorithm for target trajectory determination based on spline function representation is presented. Under least squares criterion, a nonlinear optimization strategy is applied to search the optimal spline nodes according to different trajectory characteristics. The truncation error can be eliminated and the estimated parameters in the fusion model can be reduced greatly. Therefore, the computational efficiency and estimation accuracy for the trajectory parameters will be enhanced. Finally, the calculation show the validity of the proposed algorithm, and the system errors for each measuring data can be compensated accurately. [ABSTRACT FROM AUTHOR]

The experiment studied the screening of α -galactosidase producing strain of Aspergillus niger variants and optimization of fermentation conditions. After UV mutagenesis and subculture of Aspergillus niger strain MX-H, a strain MX-H1 with stable α-galactosidase production was obtained, and its medium for enzyme production was optimized. The 18S rDNA identification showed that strain MX-H1 was identified as Aspergillus niger. The results showed that the optimal conditions were carbon source 15 g/L sucrose, nitrogen source 10 g/L beef extract, the production inducer 0.5 g/L raffinose, the initial pH 6.0, the culture temperature 30 °C, the sample size 30 mL/250 mL and the shaking table 180 r/min for 96 h. Under the optimal conditions, the activity of α-galactosidase was 4.95 U/mL. The experiment provides a reference for industrial production of α-galactosidase. [ABSTRACT FROM AUTHOR]

The near wall flow field of a high-subsonic flow simulation facility, which is used in thermal effect research of laser irradiation experiment, was calculated using CFD, and comparison of flow quality for planar and arc wall of the target material with and without side plate shows that a semi-open channel formed by side plates and the target material wall will give a broader uniform flow area in the test section. The flow measurements of the simulation facility, which was built up according to the optimized parameters based on CFD, yield good agreement with numerical results, and the flow quality can meet the requirements of laser irradiation thermal effect experiments. [ABSTRACT FROM AUTHOR]

Style investment has become a main quantitative investment approach to construct investment portfolio for funds. This paper analyzed the fractal characteristics of stock style assets returns, and revised the multifractal detrended fluctuation analysis through introducing a sliding window technique, researched on the daily return volatility characteristics of six kinds of pure stock style assets indexs introduced by Standard&Poor company, the empirical results showed that: sliding window technique can effectively reduce the fake-flutrated errors from the unconuity on junction points; daily return series of style asset indexs have relevant multifractal characteristics, the characteristics mean that the original style asset series is persistent and position reconstruction series have anti-persistence, the multifractal characteristics of position reconstruction series were significantly weaker than the multifractal characteristics of original series, which indicates enduring relevance of style asset indexs return series was the main reasons of multifractal characteristics; value&growth syle assets have stronger multifractal characteristics than the size style assets, indicating that the multi-fractal characteristics of size style assets were significantly weaker than the multifractal characteristics of value&growth syle assets. There is an important theoretical value and practical significance for fund managers timely and accuratly grasp the market style trends to construct a moderate style drift strategy. [ABSTRACT FROM AUTHOR]

The effects of W powder particle size, complexing agent, W powder loading on the electroless Ni plating on the surface of W powder are analyzed, and the morphology of coated particle, utilization rate of Ni and deposition rate are investigated. The controllable electroless Ni plating process parameters are optimized. The Ni-coated W powders are mixed with Cu powders, and then the mixed powders are sintered to prepare 67W-25Cu-8Ni alloy by using spark plasma sintering (SPS) technique. 67W-25Cu-8Ni alloy is analyzed by scanning electric microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) . Results show that, when W powder particle size is in range from 4 µm to 6 µm, the complexing agent of sodium pyrophosphate is 60 g/L, triethanolamine is 100 g/L, and trisodium citrate is 8 g/L. The Ni layer is uniform and complete, and the weight percent of Ni in W-Ni powder can be controlled by adjusting the W powder loading. Metallurgical bonding is achieved at the W/Ni/Cu interface. Compared with W-Cu alloy, the sintering density of 67W-25Cu-8Ni alloy prepared by SPS is greatly increased, reaching to 97%. [ABSTRACT FROM AUTHOR]

The ore concentration area in the southeastern Hunan is important for Nanling metallogenic belt. According to diagenetic age, composition of major-trace elements, spider diagrams and REE pattern, ore-related granites of typical deposit from the ore concentration area were selected and compared. The results show that the diagenetic ages of Mesozoic ore-related granites are mainly 150-165 Ma. According to the geochemical constituent, ore-related granites in tbe ore concentration area can be divided into two categories: firstly, the representative granite is Qitianling, lithology is mainly biotite adamellite, the plutons belong to A-type granite with high differentiation, w(Rb)/w(Sr) is high with low w(K)/w(Rb), metallogenic elements are mainly hyperthermal W and Sn, the characteristics are rich in SiO2 and alkali, and poor in P, Ti and Mg, and negative anomalies of Ba, Sr, P, Eu and Ti are significantly; for another one, the representative granite is Baoshan, the occurrence of pluton is small laccolith, lithology is mainly granodiorite, the plutons belong to I-type granite with low differentiation, w(Rb)/w(Sr) is low with high w(K)/w(Rb), negative anomalies of Ba, Sr, P, Eu and Ti are not obvious, the geochemical characteristics is similar to arc magma, and the metallogenic elements are mainly hypothermal Cu, Pb and Zn. The metallogenic characteristic of Huangshaping granite belong to the transitional type, which is between the above two kinds of ore-related granites. Combined with the tectonic background and history in the ore concentration area, the formation of ore concentration area in the southeastern Hunan is closely related to the mantle-crust interaction under the joint action of oceanic plate subduction and post-orogeny. [ABSTRACT FROM AUTHOR]