Effect of the Dispersibility of Nano-CuO Catalyst on Heat Releasing of AP/HTPB Propellant

Kneading time is adjusted to change the dispersibility of nano-CuO in AP/HTPB (Ammonia Perchlorate/Hydroxyl-Terminated Polybutadiene) composite propellants. Nano-CuO/AP is prepared to serve as the other dispersing method of nano-CuO, named predispersing procedure. Several kinds of heat releasing, thermal decomposition by DSC, combustion heat in oxygen environment, and explosion heat in nitrogen environment, are characterized to learn the effect of dispersibility of nano-CuO catalyst on heat releasing of propellants. With pre-dispersing procedures, thermal decomposition temperature of nano-CuO/AP and its propellant are about 25∘C and 8.6∘C lower than that of AP simple mixed with nano-CuO and its propellant, respectively. Comparing propellant with simple mixed nano-CuO kneading 3 hours, combustion heat and explosion heat of propellant with nano-CuO/AP increase about 1.4% and 1.7%, respectively. However, because of the breaking of nano-CuO/AP structure during kneading procedure, combustion heat and explosion heat of all the samples are decreased with the increase of kneading time after 3 hours

Mars Upper Atmospheric Responses to the 10 September 2017 Solar Flare: A Global, Time‐Dependent Simulation

We report the first global, time‐dependent simulation of the Mars upper atmospheric responses to a realistic solar flare event, an X8.2 eruption on 10 September 2017. The Mars Global Ionosphere‐Thermosphere Model runs with realistically specified flare irradiance, giving results in reasonably good agreement with the Mars Atmosphere and Volatile EvolutioN spacecraft measurements. It is found that the ionized and neutral regimes of the upper atmosphere are significantly disturbed by the flare but react differently. The ionospheric electron density enhancement is concentrated below ∼110‐km altitude due to enhanced solar X‐rays, closely following the time evolution of the flare. The neutral atmospheric perturbation increases with altitude and is important above ∼150‐km altitude, in association with atmospheric upwelling driven by solar extreme ultraviolet heating. It takes ∼2.5 hr past the flare peak to reach the maximum disturbance and then additional ∼10 hr to generally settle down to preflare levels.Key PointsIonospheric perturbation follows the flare in time and is concentrated mostly below 110‐km altitudeNeutral atmospheric perturbation increases with altitude and is important above 150‐km altitudeIt takes the neutral atmosphere 2.5 hr to reach the perturbation peak and 10 more hours to generally recoverPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151860/1/grl59414_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151860/2/grl59414-sup-0001-Text_SI-S01.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151860/3/grl59414.pd

Schizophrenia plausible protective effect of microRNA-137 is potentially related to estrogen and prolactin in female patients

BackgroundSchizophrenia (SCZ) is a serious chronic mental disorder. Our previous case–control genetic association study has shown that microRNA-137 (miR-137) may only protect females against SCZ. Since estrogen, an important female sex hormone, exerts neuroprotective effects, the relationship between estrogen and miR-137 in the pathophysiology of SCZ was further studied in this study.MethodsGenotyping of single-nucleotide polymorphism rs1625579 of miR-137 gene in 1,004 SCZ patients and 896 healthy controls was conducted using the iMLDR assay. The effect of estradiol (E2) on the miR-137 expression was evaluated on the human mammary adenocarcinoma cell line (MCF-7) and the mouse hippocampal neuron cell line (HT22). The relationships between serum E2, prolactin (PRL), and peripheral blood miR-137 were investigated in 41 SCZ patients and 43 healthy controls. The miR-137 and other reference miRNAs were detected by real-time fluorescent quantitative reverse transcription-PCR.ResultsBased on the well-known SNP rs1625579, the distributions of protective genotypes and alleles of the miR-137 gene were not different between patients and healthy controls but were marginally significantly lower in female patients. E2 upregulated the expression of miR-137 to 2.83 and 1.81 times in MCF-7 and HT22 cells, respectively. Both serum E2 and blood miR-137 were significantly decreased or downregulated in SCZ patients, but they lacked expected positive correlations with each other in both patients and controls. When stratified by sex, blood miR-137 was negatively correlated with serum E2 in female patients. On the other hand, serum PRL was significantly increased in SCZ patients, and the female patients had the highest serum PRL level and a negative correlation between serum PRL and blood miR-137.ConclusionThe plausible SCZ-protective effect of miR-137 may be female specific, of which the underlying mechanism may be that E2 upregulates the expression of miR-137. This protective mechanism may also be abrogated by elevated PRL in female patients. These preliminary findings suggest a new genetic/environmental interaction mechanism for E2/miR-137 to protect normal females against SCZ and a novel E2/PRL/miR-137-related pathophysiology of female SCZ, implying some new antipsychotic ways for female patients in future

Subjective Product Evaluation System Based on Kansei Engineering and Analytic Hierarchy Process

Product evaluation is very important for product improvement and development, and subjective product evaluation determines customer’s evaluation of products to some extent, so the purpose of this study is to establish a reasonable subjective product evaluation system. In this study, we comprehensively determine the evaluation indexes based on Kansei engineering (KE), establish an overall product evaluation system by using analytic hierarchy process (AHP), and establish the subjective product evaluation system by classifying the evaluation indexes in the overall product evaluation system into “objective evaluation index” and “subjective evaluation index”, removing the objective evaluation indexes, and retaining the subjective evaluation indexes. Additionally, we select some modern chairs as experimental samples to verify the reliability and validity of this subjective product evaluation system by means of questionnaires. The experimental results show that, in this subjective product evaluation system, the subjective evaluation of the product is positively correlated with the “favorite” level of the product in comprehensive evaluation, and negatively correlated with the “least favorite” level of the product in comprehensive evaluation, indicating that this subjective product evaluation system realizes a symmetry between subjective product evaluation and comprehensive product evaluation. Therefore, it can be concluded that this subjective product evaluation system based on KE and AHP proposed in this study has reliability and validity, and can be used for product evaluation to judge the popularity of products and enhance the competitiveness of products

Trends and Consumption Structures of China’s Blue and Grey Water Footprint

Water footprint has become a common method to study the water resources utilization in recent years. By using input–output analysis and dilution theory, the internal water footprint, blue water footprint and grey water footprint of China from 2002 to 2012 were estimated, and the consumption structure of water footprint and virtual water trade were analyzed. The results show: (1) From 2002 to 2012, the average annual internal water footprint was 3.83 trillion m3 in China, of which the blue water footprint was 0.25 trillion m3, and the grey water footprint was 3.58 trillion m3 (with Grade III water standard accounting); both the internal water footprint and grey water footprint experienced decreasing trends from 2002 to 2012, except for a dramatic increase in 2010; (2) Average annual virtual blue water footprint was the greatest in agriculture (39.2%), while tertiary industry (27.5%) and food and tobacco processing (23.7%) were the top two highest for average annual virtual grey water footprint; (3) Virtual blue water footprint in most sectors showed increasing trends due to the increase of final demand, while virtual grey water footprint in most sectors showed decreasing trends due to the decreases of total return water coefficients and conversion coefficients of virtual grey water footprint; (4) For water resources, China was self-reliant: the water used for producing the products and services to meet domestic consumption was taken domestically; meanwhile, China exported virtual water to other countries, which aggravated the water stress in China

QM/MM study of the insertion of metal ion into protoporphyrin IX by ferrochelatase

Ferrochelatase catalyzes the metallation of protoporphyrin IX in the terminal step of heme biosynthesis. Mutations in the ferrochelatase gene can lead to the disease erythropoietic porphyria. The catalyzing mechanism of ferrochelatase is still not fully understood. In this paper, we have studied the insertion of Fe2+ into the protoporphyrin IX ring by Bacillus subtilis ferrochelatase using combined quantum mechanical and molecular mechanics (QM/MM) calculations. Geometries were optimized at the BP86/6-31G* level and energies were calculated at the B3LYP/TZVP level. The overall process involves the step-wise displacement of Glu-264, His-183, and a water molecule from Fe2+, and the removal of two protons from the porphyrin ring. The rate-determining step is the cleavage of the bond between the oxygen atom of Glu-264 and Fe2+, concomitant with the formation of the first Fe-N bond. It has an energy barrier of 57 kJ mol(-1). The porphyrin ring is only slightly distorted in the enzyme active site. The residue Tyr-13 plays a key role for the catalytic process extracting two protons from protoporphyrin IX. (C) 2009 Elsevier Inc. All rights reserved

Regional Coordination and Security of Water–Energy–Food Symbiosis in Northeastern China

The interactions of water, energy, and food, which are essential resources for human survival, livelihoods, production, and development, constitute a water–energy–food (WEF) nexus. Applying symbiosis theory, the economic, social, and natural factors were considered at the same time in the WEF system, and we conducted a micro-level investigation focusing on the stability, coordination, and sustainability of the symbiotic units (water, energy, and food), and external environment of the WEF system in 36 prefecture-level cities across three northeastern provinces of China. Finally, we analyzed the synergistic safety and coupling coordination degree of the WEF system by the combination of stability, coordination, and sustainability, attending to the coordination relationship and influences of the external environment. The results indicated that the synergistic safety of the WEF system in three northeastern provinces need to equally pay attention to the stability, coordination, and sustainability of the WEF system, since their weights were 0.32, 0.36 and 0.32, respectively. During 2010–2016, the synergistic safety indexes of the WEF system ranged between 0.40 and 0.60, which was a state of boundary safety. In the current study, the coupling coordination degree of the WEF system fluctuated around a value of 0.6, maintaining a primary coordination level; while in the future of 2021–2026, it will decline to 0.57–0.60, dropping to a weak coordinated level. The conclusion could provide effective information for decision-makers to take suitable measures for the security development of a WEF system

Comprehensive Evaluation Method of Ethnic Costume Color Based on K-Means Clustering Method

Color is the external manifestation of ethnic minority culture, and the costume of each ethnic group has its objective color matching rules. In the color design of minority costumes, there is often a lack of scientific evaluation methods. Aiming at this problem, this article proposed a comprehensive evaluation method, based on the K-Means clustering method, for evaluating color matching schemes of minority costumes. We used the K-Means clustering method to analyze the objective laws of minority costume colors, and based on the objective laws found, we extracted the objective evaluation indicators. With the AHP (analytic hierarchy process) method, the judgment matrix was established to obtain the relative weights of each cultural image and objective evaluation indicator. Based on the trapezoidal fuzzy number, the user’s evaluation value of the cultural image index was clarified. The GRA-TOPSIS evaluation method was introduced to rank the color matching schemes of minority costumes. Taking the evaluation of the color matching scheme of Yi costumes as an example, this article confirmed that the proposed comprehensive evaluation method can effectively screen out the color matching schemes with the characteristics of minority costumes and can rank the color schemes to be evaluated according to their relative similarity degree to the color characteristics of minority costumes. The method integrated subjective and objective evaluations, overcame the problem of contradictory results of subjective and objective evaluations, and achieved a certain degree of symmetry between the objectivity of the color laws of minority costumes and the subjectivity of the cultural image of minority costumes. In addition, we also found the possibility of using K-Means clustering to extract the main color features of minority costumes to improve the design of color schemes

Study of the biological toxicity of oxytetracycline wastewater on zebrafish

In order to clarify the biotoxic effects of oxytetracycline wastewater, the toxicity effects of oxytetracycline wastewater on zebrafish are studied by exposure test. The results show that oxytetracycline wastewater is a low toxic substance to zebrafish. The SOD activity and POD activity of zebrafish are differently inhibited at 3~9 d. At 12 d, SOD activity and POD activity are significantly induced (0.01<P<0.05). The SOD activity of 20% volume concentration group reaches the maximum (194.05 U/mg prot), and the POD of 60% volume concentration group reaches the maximum value (2.72 U/mg prot). The SOD activity and POD activity almost returns to control values at 15 d. In addition, there is significant correlation between SOD activity and POD activity in research. The MDA content shows a "Λ" trend in each volume concentration group, and the 80% volume concentration group reaches the maximum value (5.41 nmol/mg prot) at 15 d. The content of γ-H2AX shows a rising trend in zebrafish muscle tissue. At 15 d, the 40% volume concentration group shows extremely significant (400.02 ng/L, P<0.01), which is 1.57 times that of the control group. The DNA of zebrafish muscle cells has been damaged in a certain degree. This study shows that oxytetracycline wastewater is a low toxic substance to zebrafish, and the oxidative stress of zebrafish to oxytetracycline wastewater may be one of the mechanisms causing DNA damage. The biological toxicity of oxytetracycline can provide a scientific basis for further study of the ecotoxicity effect of oxytetracycline in water environment