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Objective To investigate the application value of combining the Demirjian’s method with machine learning algorithms for dental age estimation in northern Chinese Han children and adolescents. Methods Oral panoramic images of 10 256 Han individuals aged 5 to 24 years in northern China were collected. The development of eight permanent teeth in the left mandibular was classified into different stages using the Demirjian’s method. Various machine learning algorithms, including support vector regression （SVR）, gradient boosting regression （GBR）, linear regression （LR）, random forest regression （RFR）, and decision tree regression （DTR） were employed. Age estimation models were constructed based on total, female, and male samples respectively using these algorithms. The fitting performance of different machine learning algorithms in these three groups was evaluated. Results SVR demonstrated superior estimation efficiency among all machine learning models in both total and female samples, while GBR showed the best performance in male samples. The mean absolute error （MAE） of the optimal age estimation model was 1.246 3, 1.281 8 and 1.153 8 years in the total, female and male samples, respectively. The optimal age estimation model exhibited varying levels of accuracy across different age ranges, which provided relatively accurate age estimations in individuals under 18 years old. Conclusion The machine learning model developed in this study exhibits good age estimation efficiency in northern Chinese Han children and adolescents. However, its performance is not ideal when applied to adult population. To improve the accuracy in age estimation, the other variables can be considered.

In this paper, a three-dimensional numerical framework for modeling growth of swellable soft materials at large deformation is established based on the cell-based smooth finite element method, and the multiplicative decomposition scheme of deformation gradient is given. The second P-K stress and Green's strain tensor are selected as work conjugate pairs, and the corresponding mathematical expressions of stiffness matrix and geometric stiffness matrix are derived. The numerical method is implemented based on Matlab platform, and the isotropic and anisotropic growth behaviors of swellable soft materials are simulated respectively. The results show that anisotropic growth will inhibit the deformation of expandable soft materials compared with isotropic growth. The simulation results are compared with the calculation results in the existing literature. The comparison results show that the characteristics and the morphological mode are in good agreement, which proves the effectiveness of the numerical framework in simulating the growth behavior of expandable soft materials at large deformation, and is able to reveal the mechanical mechanism of the plant growth phenomenon in nature.

In order to enhance the corrosion resistance of the cast Al - Cu - Mg - Ag alloy, a micro - arc oxidation (MAO) coating was prepared on the surface of the alloy and then sealed with silicone epoxy resin. The corrosion resistance of the Al - MAO coating system before and after sealing treatment was analyzed by electrochemical test, salt spray test and full immersion test. Results showed that after the corrosion test, the cast Al - Cu - Mg - Ag alloy corroded seriously, a large number of corrosion pits appeared along the grain boundary, and the tensile strength of alloy decreased by about 60 MPa; as for the Al - MAO coating system, the corrosion medium corroded the alloy substrate through the micro pores on the surface of the coating, a large number of white spot - like corrosion products appeared on the surface, and its tensile strength decreased by about 25 MPa. The effects of sealing treatment on the Al - MAO coating were as follows: the corrosion current density reduced from 2.62×10-8A/cm2 to 5.52×10-12A/cm2; the corrosion potential positively shifted from -589 mV to -342 mV; the low - frequency impedance increased from～105 Ω·cm2 to ～109 Ω·cm2; after the salt spray test and the full immersion test, no corrosion occurred; and the tensile strength basically remained the same. After the sealing treatment, the surface defects of the MAO coating were sealed, and a dense ceramic - organic composite coating formed on the alloy surface, which greatly reduced the corrosion rate and significantly improved the corrosion resistance of the alloy system.

After phosphate treatment, the surface of mechanical parts has color differences of film, roughness and no film, and the properties of phosphating film could not meet the process requirements. Through comparison and analysis of literature, it was found that the physical or chemical changes took place on the surface of parts while forming parts by various processing methods, which meant the surface structure, surface composition, surface stress and other states of the parts were changed; the differences of surface state had different effects on phosphating reaction rate. Therefore, different pretreatment methods should be adopted for various surface states during phosphate treatment of mechanical parts to improve the phosphating film formation condition. In this way, uniform phosphating film could be formed on the surface of parts.

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]

The intensive aquaculture-induced environmental pollution has impeded the sustainable and healthful progression of the aquaculture industry. In order to explore a more sustainable and efficient aquaculture model, we enhanced the circulating aquaculture system in freshwater ponds in this study. The physicochemical indexes and nitrogen and phosphorus budget of ponds were analyzed during the 5-month experiment period. The results showed fluctuating changes in the physicochemical indexes of pond water, with total nitrogen and total phosphorus concentrations measuring 4.85 and 1.04 mg/L, respectively, at the end of the experiment. Notably, the total nitrogen concentrations met the secondary standards for freshwater aquaculture tailwater discharge. Feed and sediment emerged as principal contributors to nitrogen and phosphorus input, accounting for 50.6% and 43.7% of nitrogen input and 49.4% and 46.9% of phosphorus input, respectively. Sediment accumulation emerged as the primary mechanism for nitrogen and phosphorus output in ponds, accounting for 53.3% and 78.7% of nitrogen and phosphorus output, respectively. The nitrogen and phosphorus utilization rates in experimental ponds were determined to be 65.2% and 16.6%, respectively. The utilization rate of nitrogen and phosphorus of carp (Cyprinus carpio) were significantly higher than those of other fish (P<0.05). However, there was no significant difference in the phosphorus utilization rate between silver carp (Hypophythalmichthys molitrix) and bighead carp (Aristichthys nobilis) (P>0.05). The research shows that the enhanced pond circulation aquaculture system can effectively mitigate nutrient load, enhance the nitrogen and phosphorus utilization rate of aquaculture organisms, diminish the impact of aquaculture tailwater on the surrounding environment, and concurrently consider ecological and economic benefits. It represents a low cost, environmentally friendly, and healthful pond aquaculture model. [ABSTRACT FROM AUTHOR]

A mesoporous material of Fe-Zr(P) was synthesized by modifying the bimetallic material of Fe-Zr with polyether P123. Then, TEPA(n)/Fe-Zr(P) was prepared by modifying Fe-Zr(P) with tetraethylenepentamine (TEPA). X-ray diffraction, infrared spectroscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption and thermogravimetric analysis were used to analyze the structure and thermal stability of the synthesized materials. The results show that P123 is remained in the pore channels of the support. Besides, TEPA was introduced to the surface of Fe-Zr(P) through the coordination between N and Zr species. The adsorbents filled with P123 and TEPA keep stable when the temperature is less than 182℃. In addition, the adsorbents exhibit good CO2 adsorption performance in a stream of 5% CO2 concentration. Over TEPA(n)/Fe-Zr(P), both of the hydroxyl and amine groups react with CO2, leading to the occurrence of CO2 chemical adsorption and the enhancement of adsorption capacity and N utilization. When the mass fraction of TEPA is 30%, a remarkable adsorption capacity of 211.3 mg/g and the utilization of N species of 62.7% are achieved at 75℃ in a stream of 10 mL/min. After 20 cycles of adsorption-desorption, the adsorption capacity keeps stable.

The core-shell structured CoNiCrAlY-Al2O3 powders were well-designed and fabricated with the Al2O3 as the shell. The ball milling preparation process of core-shell structured powders was optimized by orthogonal experiment design. The phase structure and microstructure evolution of the high velocity oxy-fuel sprayed(HVOF) CoNiCrAlY-Al2O3 coatings caused by using of core-shell structured powders were discussed. The oxidation behavior of HVOF CoNiCrAlY coating and CoNiCrAlY-Al2O3 composite coating at 800 ℃ was comparatively studied.The results show that the influence of the process parameters on the average coating rate of the core-shell structured powders in descending order are: ball milling rotation speed, mass ratio of ball to powder and ball milling time.The optimal ball milling parameters for preparing CoNiCrAlY-Al2O3 core-shell structured powders are: ball milling rotation speed of 180 r/min, mass ratio of ball to powder of 10∶1, and ball milling for 6 h. The HVOF CoNiCrAlY coating is mainly composed of γ-Co-Ni-Cr phase.The oxidation behavior of CoNiCrAlY alloy during spraying process is significantly inhibited by the using of core-shell structured raw powders. Due to the existence of the high melting point Al2O3 shell in the raw powders, the CoNiCrAlY-Al2O3 composite coating contains a high content of β-NiAl phase. In addition, the coating has high porosity and high content of un-melted particles.Compared with CoNiCrAlY coating, CoNiCrAlY-Al2O3 composite coating has excellent high temperature oxidation resistance. The high content of β-NiAl and Al2O3 in the composite coating leads to the formation of a dense Al2O3 rich protective layer on the surface of the coating during high temperature oxidation. The oxide film significantly inhibits the growth of non-protective oxides.

Objective To determine the expression and function of G protein-coupled receptor 84 (GPR84) in rat cerebral ischemia-reperfusion(I/R). Methods The rat middle cerebral artery occlusion (MCAO) models were performed, and rats were then divided into sham group, cerebral ischemia for 2 h and reperfusion for 12 h group (I/R 12 h), 24 h group (I/R 24 h), 48 h group (I/R 48 h), 72 h group (I/R 72 h); rat primary cortical neurons were isolated and cultured in vitro, neurons were then divided into control group (control), oxygen-glucose deprivation (OGD) for 1 h and recovery for 24 h group (OGD/R 1 h), OGD for 2 h and recovery for 24 h group (OGD/R 2 h); neurons were transfected with GPR84 small interfering RNA (siRNA), cells were divided into control group, OGD/R 1 h group, neurons pretreated with negative control and exposed to OGD for 1 h and recovery for 24 h group (NC+OGD/R 1 h), neurons pretreated with GPR84 siRNA and exposed to OGD for 1 h and recovery for 24 h group (GPR84 siRNA+OGD/R 1 h). Western blot was used to determine the expression of GPR84 protein. Immunofluorescence assay was used to analyze the localization of the immunofluorescence signals of GPR84 in cerebral ischemic tissues after MCAO. TdT-mediated dUTP nick end labeling (TUNEL) assay was used to detect the percentage of apoptotic neurons. Results Compared with the sham group, the expression of GPR84 protein was significantly up-regulated at each time point after cerebral I/R(P＜ 0.01). In addition, GPR84 was mainly localized in neurons and microglia, while little GPR84 was found in astrocytes. Neurons in the MCAO group showed a higher level of GPR84 expression than those in the sham group. GPR84 knockdown significantly inhibited the increase of GPR84 expression induced by OGD/R. Compared with the control group, neurons in the OGD/R 1 h group exhibited higher apoptotic cells percentage. Compared with the NC+OGD/R 1 h group, the percentage of apoptotic neurons in GPR84 siRNA +OGD/R 1 h group was significantly decreased. Conclusions These results suggest that the elevated GPR84 expression induced by cerebral I/R may play an important role in cerebral ischemia injury.

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]

In order to study the band gap performance of structural color films under different conditions, Monodisperse submicron silica microspheres with different particle sizes were prepared by the modified Stöber method, and a photonic crystal structure color film with silica as a structural element was prepared on the surface of the glass by vertical deposition self-assembly. The morphology and optical properties of microspheres and films were analyzed by scanning electron microscope, infrared spectrometer and UV-vis spectrophotometer. The results show that during the synthesis process, with the increase of the reaction temperature, the particle size of silica microspheres gradually reduces; with the increase of the diameter of SiO2 microspheres, the corresponding photonic band gap of photonic crystals occurs red shifting. It is found through further study that as the angle between the incident light and the normal line of color film increases, the center wavelength corresponding to the photonic band gap becomes shorter, then blue shifting occurs.

In order to study the nature of interaction between Ba2+ and the KDP crystal surface, the adsorption behavior of Ba2+ on the KDP (100) surface was calculated by using density functional theory (DFT). The results show that the adsorption energies of Ba2+ on the KDP (100) surface are negative, indicating the adsorption processes are spontaneous and exothermic. Three types of adsorption configurations are formed after structure optimizations, and final adsorption positions are top sites on O atoms or bridge sites between two O atoms. The most stable adsorption system can be observed when Ba2+ on the bridge site between two O atoms within a phosphate group. In the three different adsorption configurations, Ba2+ can form ionic bonds with the surface O atoms, while interactions between Ba2+ and the surface H atoms exhibit covalent character. The P-O, H-O, and K-O bonds on the KDP (100) surface are elongated or shortened after Ba2+ adsorption, and the structure of hydrogen bonds on the surface also have been changed significantly.

To comprehensively assess the quality of flue-cured tobacco, an entropy weight method and a modified Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)method were used to evaluate the appearance, sensory quality, and routine chemical composition consistency of 114 flue-cured tobacco samples. The proximity for the appearance, sensory quality, chemical composition, and comprehensive quality were obtained, and the correlations between the different comprehensive quality indices and each quality proximity were analyzed using a simple correlation analysis method. The results showed that: 1)The weights of the appearance, sensory quality and chemical composition calculated by the entropy weight method were about 0.316, 0.380, and 0.304, respectively. 2)The flue-cured tobacco with fresh-sweet flavor from Taiping Town, Huili County, Liangshan Prefecture, Sichuan Province; Miyang Town, Mile City, Honghe Prefecture, Yunnan Province; Lin' an Town, Jianshui County, Honghe Prefecture, Yunnan Province; Lixi Town, Huili County, Liangshan Prefecture, Sichuan Province; and Cida Town, Dechang County, Liangshan Prefecture, Sichuan Province had better comprehensive quality. 3)The indices that positively correlated with the comprehensive quality of tobacco with fresh-sweet flavor included color intensity, body, oil, color and leaf structure, the vast majority of sensory quality indicesdryness, mellowness, aroma quantity, offensive odor, volatility, aftertaste, aroma quality, extent, irritation, smoothness and industrial usability), and total alkaloids and reducing sugar/total sugar ratios in leaf chemical compositions. [ABSTRACT FROM AUTHOR]

At present, free α-SiO2 content is often determined by the pyrophosphate method and X-ray Diffraction (XRD) method. However, insoluble materials including FeO, Fe3O4 and Fe2O3 in mill scale cannot be decomposed by pyrophosphate, and thus the pyrophosphate method is not suitable for the determination of free α-SiO2 content in mill scale. A method for detecting free α-SiO2 content in mill scale through X-ray diffraction K value method has been developed. α-Al2O3 was used as the reference material. Diffraction peaks of crystal face (101) for α-SiO2 and crystal face (012) for α-Al2O3 were used for measured diffraction peaks. Samples for detecting K value were prepared by mixing α-SiO2 with α-Al2O3 at a mass ratio of 1:1. The acquired K value is 7.86. The measured K value has been applied to the determination of mill scale samples with known free α-SiO2 content, and the analytical results of free α-SiO2 content are in good agreement with practical values. Detection range of this method is that free α-SiO2 are equal or greater than 0.5%. This method is convenient and rapid, and has a wide detection range and can meet the need of imported mill scale inspection and supervision work.

The spaceborne sodium Doppler lidar can be developed to measure global wind, temperature and sodium number density in the mesopause and lower thermosphere region. In order to analyze the feasibility of the lidar, simulation calculations about backscattering signals and measurement accuracy have been done in this paper. The analyzed result shows that the line-of-sight wind accuracy, horizontal wind accuracy and temperature accuracy are 0.8 m/s, 1.5 m/s and 2.5 K when the height of satellite orbit is 400 km, observational angle is 30.0°, laser power is 9.0 W, receiver diameter is 1.0 m, vertical range resolution is 2.0 km, and signal integrated time is 30.0 s.

The quadrature signal generator is widely used in devices such as the quadrature modulator and image rejection frequency converter. An RC polyphase network is commonly used as a quadrature signal generator because of its simple structure and perfect linear performance. This study derives explicit transfer functions for the RC polyphase network based on the complex signal properties and the matrix theory. Moreover, build-related parameters are determined to analyze the I/Q amplitude and phase balance characteristic of the RC polyphase network, thus providing a theoretical guideline for the design of a high-balance quadrature signal generator.

Fluorine content in geological sample ore is often detected by Fluorine Ion Selective Electrode. This method does not meet the demands of analysing large amounts of imported copper ores, due to it being a complicated procedure with a lengthy analysis period. Major and minor components in copper ores have been detected by X-ray Fluorescence Spectrometry using the fusion method for sample preparation, but this method cannot detect fluorine content. In this paper, the method for detecting fluorine content in imported copper ores is presented by using Wavelength Dispersive X-ray Fluorescence Spectrometry with pressed powder preparation. A calibration curve was established by using fifteen practical imported copper ore samples whose granularity was 0.074 mm. The application of the empirical coefficient method significantly reduced the particle and mineral effect, and the matrix effect. The relative standard deviation (RSD, n=11) of fluorine determined in imported copper ores was 0.30%. The detection limit of the method was 2.4 μg/g and the measuring range was from 0.030 % to 0.20%. The method has been applied to the determination of fluorine in standard materials and practical samples, and the analytical results were in good agreement with certified values of standard materials and values of practical samples determined by Fluorine Ion Selective Electrode. This method meets the routine inspection needs of fluorine content in imported copper ores, which is less than 0.10%.

[Objectives] To determine the role of nitrogen in the population explosion of the Asian corn borer, Ostrinia furnacalis (Guenee), we compared the effects of artificial diets with different nitrogen contents on food utilization by, and nutritional content of, this species. [Methods] Five artificial diets (N1, N2, N3, N4 and N5) with nitrogen contents of 3.94%, 7.33%, 10.69%, 18.84% and 30.31% were fed to 3rd, 4th and 5th-instar larvae, and differences in food utilization and larval nutritional indices between treatment groups were compared and analyzed. [Results] The highest food utilization rate (16.28% ± 0.89%) and food conversion rate (41.05% ± 4.07%) was recorded in 3rd instar larvae in the N3 treatment group, significantly higher than the corresponding values in the N4 and N5 treatment groups. The lowest food utilization and food conversion rate, 3.32% ± 0.57% and 2.36% ± 0.69%, respectively, were recorded in the N2 treatment group. The highest food utilization rate in 4th instar larvae, 22.13% ± 1.51%, was recorded in the N5 treatment group. 5th instar larvae in the N5 and N4 treatment groups had the highest food utilization and approximate digestibility; 24.29% ± 7.01% and 40.93% ± 2.94%, respectively, but dietary nitrogen had no significant effect on food conversion and relative growth rates (P > 0.05). The nitrogen use efficiency of 3rd, 4th and 5th-instar larvae all increased with dietary nitrogen content; the highest nitrogen use efficiencies for each instar (72.33%, 86.09% and 90.91%, respectively) were all recorded in the N5 treatment group. [Conclusion] Dietary nitrogen has a direct impact on food utilization by, and the nutritional indices of, Asian corn borer larvae, and dietary nitrogen significantly increased food use efficiency, relative feeding rate and nitrogen use efficiency of 4th-instar and 5th-instar larvae. [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]

In view of problem of bad effect of image collected by industrial endoscope because of special application place, the paper proposed an image fusion algorithm based on multi-scale wavelet transform and different fusion operators. Firstly, it made wavelet transform for source image, then used simple average algorithm to fuse low frequency coefficients which represents approximate information and used dynamic weighting average algorithm based on local deviation to fuse high frequency coefficients which represent detail information. Finally, it made inverse wavelet transform of processed low and high frequency coefficients to get fused image. The experiment result showed that the algorithm improves image processing effect with better image parameters comparing with other algorithms.

The paper proposed a scheme of magnetic tracking navigation of autonomous mobile patrolling robot on fully mechanized coal face of coal mine underground. The scheme defines magnetic tracking material and magnetic sensor of the robot as stripy magnet with high intensity magnetic and model MS-324 tongue tube through experiment, it defines installing position and working process of the tongue tube of the robot with example of collecting underground image information by wheeled robot. The experiment result showed that the robot can moves stably when distances between two tongue tubes are 40 mm.

As one of the most important key words in ethical literary criticism, scientific selection as theory is not equivalent to scientific choice as terminology in critical practice. The former refers to the third stage of choices after the natural selection and ethical selection, mainly tackling the problem of the combination of science and humans; while the latter focuses on the action of choice based on scientific norms. No matter in reality or in science fiction, the results of scientific selection exist everywhere. With the narration in science fiction of robots, androids, human cloning and immortality, the paper attempts to sort out the denotation and connotation of this keyword, helping to understand humans' cognition and transformation to nature. However, the scientific choice narrated in the novels is still the result of humans' ethical consciousness and ethical choice, which refers to the initial stage of scientific selection. The real scientific selection means a stage where science replaces ethics, that is, by virtue of technological products, humans develop from human extension to human deconstruction and turn into "humans by scientific choice". Strictly speaking, scientific selection, separating from ethics, has not yet arrived; nonetheless, science fiction has expounded how humans develop and use technology from the perspective of scientific choice, predicting the impacts and consequences science has exerted on humans, thus prompting us to consider the hybrid and coexistence of science and humans in the future. [ABSTRACT FROM AUTHOR]

The story of William Gibson's Count Zero unfolds around biochips. The three interlocking narrative threads that follow Turner, Bobby, and Marly respectively might seem to be out of focus, but they describe how humans break through the real physical space, enter the cyberspace gradually, and construct a new community eventually. With the help of Deleuze's concepts, such as "rhizomes," "deterritorialization," and "becoming," we may find out that the three dimensions of hackers, simstim, and cyber expound the becoming patterns and characteristics of cyberspace community: virtual technologies deterritorialize the space of bodily co-presence and establishes places for the interaction between hackers and people from all levels of hierarchy; the ethical relationships and emotions between self and others, subjects and objects in cyberspace need simstim to generate an equally authentic experience of togetherness, rather than a transcendental representation; cyber-technologies reterritorialize the virtual and real geographic spaces, enabling the cyberspace to construct new concepts of nation and world. Given the essence of cybernetics, however, the alienation of human nature and moral crisis also exist in the cyberspace community. Therefore, the prevision of a posthuman cyberspace in Count Zero is still imbued with sentiments of humanism. [ABSTRACT FROM AUTHOR]

In order to reveal the variation law and driving factors of runoff and sediments in the upper reaches of the Yellow River, according to the time series data of three representative hydrological stations in the upper reaches of the Yellow River, average difference T methods, double cumulative curve method, wavelet analysis, cumulative slope rate change rate method and other methods are used to analyze and study the characteristics of runoff and sediment change in the upper reaches of the Yellow River. The results show that the runoff and sediment discharge of the three representative stations in the upper reaches of the Yellow River showed a decreasing trend from 1960 to 2019. The annual runoff at Tangnaihai Station, Lanzhou Station and Toudaoguai Station in the upper reaches of the Yellow River havean abrupt change in 1989, 1985 and 1985, and the annual sediment load of the three stations abrupt change in 1989, 1999 and 1985. Wavelet analysis is used to find that runoff has a main cycle of 9~16 a, and sediment discharge has a main cycle of 11~16 a. The cumulative sediment reduction of the three stations in the upper reaches of the Yellow River is about 107 million t, 1.1 billion t and 1.639 billion t, respectively, and the sediment reduction increased along the river. The variation law of runoff and sediment is influenced by precipitation and human activities, and human activities play an important role in the variation of water and sediment. [ABSTRACT FROM AUTHOR]

In order to reduce the crosstalk between the densely arranged polymer micro-nano fibers, this paper proposes to analyze the dependence of crosstalk on the intersection angle, diameter, separation, modal polarizations and wavelength of two intersecting polytrimethylene terephthalate micro-nano fibers using the Finite Difference Time Domain (FDTD) method. The results suggest that the crosstalk decreases with the increase of the intersection angle and separation. From the single-mode cutoff diameter, the crosstalk increases with decreasing diameter until reaching a maximum value, and then decreases afterward. Additionally, the crosstalk is lower in the X direction polarization and is smaller at the wavelength of 1 550 nm. These results provide good guidance and reference value for the construction of complex ultra-compact photonic devices and miniaturized integrated optical circuits. [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]

Automatic extraction of buildings from satellite remote sensing images has a wide range of applications in the development of economy and society. Due to the influence of mutual occlusion, illumination, background environment and other factors in satellite remote sensing images, it is difficult for traditional methods to achieve high-precision building extraction. This paper proposes an attention enhanced feature pyramid network (FPN-ENet) and constructs a large-scale pixel-wise building dataset (SCRS dataset) by using multi-source high - resolution satellite images and vector data to realize the automatic extraction of buildings from multi -ource satellite images, and compares it with the other full convolution neural networks. The results show that the accuracy of building extracted from SCRS dataset is close to the world's leading open source satellite image dataset, and the accuracy of Pseudo color data is higher than that of true color data The accuracy of FPN - SENet is better than that of other full convolution neural networks. The extraction of building can also be improved by using the sum of cross entropy and Dice coefficient as the loos function. The overall accuracy of the best classification model is 95. 2%, Kappa coefficient is 79. 0%, and F1 - score and IoU are 81. 7% and 69. 1% respectively. This study can provide a reference for building automatic extraction from high-resolution satellite images. [ABSTRACT FROM AUTHOR]

In order to improve the quality of dried peanut pods, we had coupled hot air with pulse intermittent low-intensity microwave, high-intensity microwave, and high & low intensity microwave respectively in the drying process. Drying characteristics, peanut pods quality and drying energy consumption of different drying processes were analyzed. The result showed that the best process was to combine hot air with pulse intermittent and high & low intensity microwave. With an irradiation of 0.95 W/g microwave for 16.7 min and 0.48 W/g microwave for 11.7 min, the moisture content of peanut pods was reduced from 50.0% to 15.5% in 198.3 min, and the total energy consumption of the process was respectively 37.1% and 8.6% lower, the quality of dried peanut pods was better. Therefore, analysis of the drying process which couples hot air with pulse intermittent and high & low intensity microwave is of vital importance to wastage reduction of peanut pods. [ABSTRACT FROM AUTHOR]

With the rapid socioeconomic development the multi-project synergistic management mode based on "program" has gradually become a prevailing management trend which has broken up the fixed thinking of traditional organizational management mode centering on single project. To deepen program synergistic management of enterprise project and optimize performance of multi-project synergy management the organizational management mode considering the internal synergistic effect among projects was proposed the multi-level vertical synergistic organization mode of "enterprise strategy-project program-project" was constructed by combining the organizational hierarchy analysis theory secondly the horizontal synergy organization mode was proposed by analyzing the synergistic relationship among project elements finally the organization framework of comprehensive synergistic management of enterprise project was constructed by integrating the synergy characteristics from vertical and horizontal perspectives based on the information platform which can provide theoretical reference for enterprises to implement project program synergistic management and construct scientific management system. [ABSTRACT FROM AUTHOR]

Low temperature stresses (-3 and -5 °C) were simulated using artificial temperature controlled phytotrons to study the freezing rate, the contents of endogenous hormones, and the activities of antioxidative enzymes in the leaves of wheat plants of Yangmai 16 (YM 16) and Xumai 30 (XM 30) at jointing stage. The grade and index of freezing injury increased with lower temperature and longer stress. The freezing rate was at the 5th level and the main stems and tillers of both cultivars were finally dead under -5 °C lasting for 72 h. On the last day of stress initiation, the contents of abscisic acid (ABA) and zeatin riboside (ZR), and the activities of superoxide dismutase (SOD), peroxide dismutase (POD), and catalase (CAT) in leaves increased at the beginning and then declined as low temperature progressed. On the 3rd day after stress, the contents of ABA and ZR and the activities of antioxidative enzymes were higher than those on the last day of cold stress, and then reduced to the level of the control on the 6th day after stress. The content of gibberellins (GA3) was lowered by cold stress. For YM 16, GA3 content increased from the 3rd day to the 6th day after cold stress, whereas, for XM 30, it increased first and then decreased. For the treatment of -5 °C lasting for 72 h, the contents of hormones and the activities of antioxidative enzymes were significantly lower than those of the other treatments. Correlation analyses showed that higher ABA and ZR contents, and higher SOD, POD and CAT activities as well as lower GA3 content could alleviate the low-temperature injury in wheat plants under low temperature stress. [ABSTRACT FROM AUTHOR]

As a particular phenomenon in human society, religion exerts a far--reaching influence on individual's ideology, behavior and life style, by means of a specific religious belief. It functions as stabilizer for social order by accepting people's social relationship, social status and social role. The causes for Jinzhou City residents' belief in Christianity and Catholicism are as follows: personal rational thinking, attraction by the religious belief, utilitarianism in real life, loneliness in life, soul comfort, family tradition, etc. [ABSTRACT FROM AUTHOR]

To access to the complex and unpredictable environment where the ground may be soft or hard alternately, a transformable wheel/track robot was proposed, which could travel over relatively smooth terrain quickly and move on uneven terrain well. The robot consists of a control box unit, two symmetric transformable wheel/track units and a tail sting unit. In the paper, the system structure and key mechanical points-including the positioning method of the walking wheels, the four-bar linkage conversion mechanism and the retractable track were presented, and then the obstacle climbing ability was analysed. The result shows that, the walking wheels are fixed firm, and the four-bar linkage conversion mechanism and the retractable track can quickly switch between in wheel mode and track mode, and the robot can successfully cross steps and stairs, which would lay the foundation for researching new mobile mechanism and wheel-track mechanism technique. [ABSTRACT FROM AUTHOR]

In order to overcome the disadvantages such as long time surveying, large workload, high cost and difficulties in surveying points protection of the conventional surface movement surveying method, the surface subsidence basin due to high-intensity longwall caving mining was scanned and studied by use of 3D laser scanning technology. According to the data analysis of 3D laser scanning and comparison with the conventional surface movement surveying method, the 3D digital elevation model of the surface subsidence basin due to high-intensity coal mining was set up. The results showed that the 3D laser scanning technology could obtain the whole surface subsidence basin data high efficiently and rapidly and the root mean square error was 0.012 7 m, it was feasible to monitor the surface subsidence basin. With the efficient data collection velocity of this technology, it has preferable application and generalization prospects in mining subsidence data monitoring. [ABSTRACT FROM AUTHOR]

With the recent development and application in agricultural research, the high-throughput sequencing technology offers new opportunities to speed up the breeding process for new banana variety improvement .This paper aimed to review the damage and control measures of banana Fusarium wilt, as well as the development of high - throughput sequencing technology and its application in banana resistant to diseases. At present, the related researchers have found that the Foc infection to banana was associated with the JA signaling pathways , and the genes encoding ethylene synthetase ACC oxidase and ethylene response transcription factor (ERF & could strongly express after pathogen infection to banana. In the future, high-throughput sequencing technologies should be applied to study the banana genome. On the basis of finishing banana genomic sequencing, the gene resources of banana resistance mutants against Fusarium wilt should be exploited by using transcriptome technologies to get genes and loci of banana resistant mutants against Foc4. The related genomic regions of species phenotypic variation should be mapped precisely by combining with comparative genomics and bioinformatics to accelerate the exploitation and application of unknown functional genes in banana. The important resistant control genes should be cloned to master its disease resistance law, which could provide references and indirections on controlling banana Fusarium wilt and accelerate resistant varieties breeding process for getting new varieties with lasting resistance. [ABSTRACT FROM AUTHOR]

To solve the low speed problem of two-wheeled robot in turn path, a mechanism design method of a new two-wheeled robot which could swing at axis direction was presented in this paper. A bar was designed to control the swing of the robot. The mechanism changed the gravity center of the robot, which made the robot much easier to cope with turn path. More specifically, it means that the robot could run in the small radius surface steadily. The dynamic analysis of the addition freedom degree had done by Lagrange equation to get the dynamics equation. And a state feedback controller was designed based on the equation. A simulation of the controller was executed based on Matlab/Simulink. The simulation results prove that the design of the controller was effective for the stable control. It also indicates that the mechanical design method and motion control system of the two-wheeled robot can improve the robot's kinetic stability effectively. [ABSTRACT FROM AUTHOR]

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