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The Chinese Software Developer Network (CSDN) is one of the largest information technology communities and service platforms in China. This paper describes the user profiling for CSDN, an evaluation track of SMP Cup 2017. It contains three tasks: (1) user document keyphrase extraction, (2) user tagging and (3) user growth value prediction. In the first task, we treat keyphrase extraction as a classification problem and train a Gradient-Boosting-Decision-Tree model with comprehensive features. In the second task, to deal with class imbalance and capture the interdependency between classes, we propose a two-stage framework: (1) for each class, we train a binary classifier to model each class against all of the other classes independently; (2) we feed the output of the trained classifiers into a softmax classifier, tagging each user with multiple labels. In the third task, we propose a comprehensive architecture to predict user growth value. Our contributions in this paper are summarized as follows: (1) we extract various types of features to identify the key factors in user value growth; (2) we use the semi-supervised method and the stacking technique to extend labeled data sets and increase the generality of the trained model, resulting in an impressive performance in our experiments. In the competition, we achieved the first place out of 329 teams.

In this paper, the bimetallic metal–organic frameworks (MOFs) of FeNi-BDC and FeNi-BDC-NH2 (BDC, 1,4-benzenedicarboxylate) with similar Fe/Ni molar ratio, crystal structure, porosity and thermal stability were synthesized by a solvothermal method. The results of adsorption experiments at ambient conditions showed that the adsorptive uptake of NO, CO2, O2 and N2 on FeNi-BDC were all very small under different adsorption partial pressures, with FeNi-BDC displaying a weak adsorption property because of its lack of unsaturated adsorption sites. On the contrary, at 100 kPa, the adsorption of NO by FeNi-BDC-NH2 was considerably higher than that by FeNi-BDC, indicating that the incorporation of NH2 on the ligand could effectively enhance the adsorption of NO. The adsorption capacity of FeNi-BDC-NH2 for NO reached 142.17 cm3 g−1, which was considerably higher than its capacity for CO2, O2 and N2 under the same conditions. Ideal Adsorption Solution Theory simulations calculated the adsorption selectivity for NO/CO2 and NO/O2 under a mixed atmosphere to reach 1325 and 13,346 respectively, demonstrating high adsorption selectivity. Through in situ infrared experiments and calculations of the enthalpy of adsorption, it was demonstrated that FeNi-BDC-NH2 adsorbed NO because NO can combine with NH2 in the material to form a NONOate structure. A preliminarily exploration of the mechanism of NO adsorption and the influence of NH2 functional groups on the adsorption and separation of NO revealed that the selectivity of adsorption was closely related to the variability of the enthalpy of adsorption. This also provided a new strategy for the adsorption and separation of NO in the flue gas environment. The bimetallic metal–organic frameworks of FeNi-BDC and FeNi-BDC-NH2 (BDC, 1,4-benzenedicarboxylate) with similar Fe/Ni molar ratio, crystal structure, porosity and thermal stability were synthesized by a solvothermal method. FeNi-BDC-NH2 demonstrated superior NO adsorption performance and high adsorption selectivity, indicating that the introduction of NH2 on the ligand can improve the adsorption capacity and selectivity of the material for NO, which also provides a new strategy for adsorption and separation of NO in a flue gas environment. (Image credit: Li Hao.) [ABSTRACT FROM AUTHOR]

In this work, the effect of amine groups of MOFs materials on the NO separation selectivity under the simulated mixed atmosphere had been first investigated by comparison of NO adsorptive separation selectivity of Fe‐BDC, Al‐BDC, FeAl‐BDC and Fe‐BDC‐NH2, Al‐BDC‐NH2, FeAl‐BDC‐NH2 synthesized by solvothermal method. The experimental results showed that the adsorption capacity of NO by Fe‐BDC‐NH2, Al‐BDC‐NH2, and FeAl‐BDC‐NH2 was significantly larger than Fe‐BDC, Al‐BDC, and FeAl‐BDC at 100 kPa, which indicated ‐NH2 promotes the adsorption of NO and was much higher than the adsorption capacity of CO2, O2, and N2 under the same conditions. The NO adsorption capacity and selectivity of bimetallic FeAl‐BDC‐NH2 were significantly better than that of monometallic Fe‐BDC‐NH2 and Al‐BDC‐NH2. The NO adsorption capacity of FeAl‐BDC‐NH2 can reach 216.42 cc g−1, which exceeded lots of MOFs materials reported, and the adsorption selectivities of NO/CO2 and NO/O2 by IAST under the simulated mixed atmosphere reached 1,350 and 15,962. It also proved that the material adsorbed NO because NO forms NONOate with ‐NH2 by the in situ IR and enthalpy calculation of adsorption, and the adsorption mechanism of NO was preliminarily investigated. The results provided a new direction for the application of adsorption and separation of NO in flue gas. [ABSTRACT FROM AUTHOR]

This article was the first to prepare CeZrNiOx ternary solid solution using CeZrNi BDC MOFs as a template, and investigate its effect on improving the dispersion stability of Pd components in three‐way catalysts and the catalytic performance of natural gas exhaust purification. The experimental results indicated that CeZrNiOx derived from CeZrNi‐BDC MOFs had a stable solid solution uniform structure and relatively good thermal stability of the porous structure. Therefore, the thermal stability of Pd/CZN−M derived from CeZrNi BDC MOFs was significantly better than that of Pd/CZN−C prepared by citric acid complexation method. The PdO particle size of Pd/CZN−M before and after thermal aging was only about 2.0 and 4.5 nm, respectively. At GHSV50000 ml/(g⋅h), the T90 of aged Pd/CeZrNiOx for CH4, NO, and CO reached 410, 370, and 175 °C, respectively, showing better three‐way catalytic (TWC) activity than reported in existing literature. In addition, CeZeNiOx carriers derived from MOFs also enhanced the co‐activation ability of NO and CH4, and exhibited certain activity in the low‐temperature self‐decomposition reaction of NO, thus showing significant advantages in the TWC catalytic activity of NGVs. This work would provide a new method for preparing NGVs exhaust TWC catalysts with high dispersion stability. [ABSTRACT FROM AUTHOR]

The melanocortin 4 receptor (MC4R) plays a critical role in the long-term regulation of energy homeostasis, and mutations in the MC4R are the most common cause of monogenic obesity. However, the precise molecular and cellular mechanisms underlying the maintenance of energy balance within MC4R-expressing neurons are unknown. We recently reported that the MC4R localizes to the primary cilium, a cellular organelle that allows for partitioning of incoming cellular signals, raising the question of whether the MC4R functions in this organelle. Here, using mouse genetic approaches, we found that cilia were required specifically on MC4R-expressing neurons for the control of energy homeostasis. Moreover, these cilia were critical for pharmacological activators of the MC4R to exert an anorexigenic effect. The MC4R is expressed in multiple brain regions. Using targeted deletion of primary cilia, we found that cilia in the paraventricular nucleus of the hypothalamus (PVN) were essential to restrict food intake. MC4R activation increased adenylyl cyclase (AC) activity. As with the removal of cilia, inhibition of AC activity in the cilia of MC4R-expressing neurons of the PVN caused hyperphagia and obesity. Thus, the MC4R signaled via PVN neuron cilia to control food intake and body weight. We propose that defects in ciliary localization of the MC4R cause obesity in human inherited obesity syndromes and ciliopathies., Introduction Most mammalian cells, including neurons, possess a single, immotile primary cilium, an organelle that transduces select signals (1). Defects in the genesis or function of primary cilia cause a [...]

SARS-CoV Spike (S) protein shares considerable homology with SARS-CoV-2 S, especially in the conserved S2 subunit (S2). S protein mediates coronavirus receptor binding and membrane fusion, and the latter activity can greatly influence coronavirus infection. We observed that SARS-CoV S is less effective in inducing membrane fusion compared with SARS-CoV-2 S. We identify that S813T mutation is sufficient in S2 interfering with the cleavage of SARS-CoV-2 S by TMPRSS2, reducing spike fusogenicity and pseudoparticle entry. Conversely, the mutation of T813S in SARS-CoV S increased fusion ability and viral replication. Our data suggested that residue 813 in the S was critical for the proteolytic activation, and the change from threonine to Serine at 813 position might be an evolutionary feature adopted by SARS-2-related viruses. This finding deepened the understanding of Spike fusogenicity and could provide a new perspective for exploring Sarbecovirus' evolution. Author summary: The Spike of SARS-CoV-2 has accumulated many mutations during its time in circulation, most of which have occurred in the S1 region, and more specifically in the RBD, in an effort to either improve the virus's affinity for the receptor ACE2 or to enhance its ability to evade the immune system. Mutations in the Spike S2 region have more far-reaching effects than those in the S1 region because it is more conserved across Sarbecoviruses. By comparing SARS-CoV and SARS-CoV-2, we found that an important substitution at amino acid position 813 in the S2 region (T813S) disrupts the utilization of TMPRSS2 and can significantly influence viral entry into cells. This discovery deepens our knowledge of S proteins and provides new prospects for tracing the evolution of Sarbecoviruses. [ABSTRACT FROM AUTHOR]

The effect of MOFs-derived Ce0.3Ni0.7Ox carrier (CN-M) on Pd dispersion states for three-way catalytic (TWC) performance of natural gas vehicles (NGVs) comparing with Ce0.3Ni0.7Ox carrier (CN-C) prepared by citric acid complexation method has been studied. The results showed that the Pd/CN-M catalyst displayed better Pd dispersion (46.3%) and much higher activity for the conversions of CO, NO and CH4. Both T50 and T90 of CO conversion over Pd/CN-M were lower ca. 100 °C than that over Pd/CN-C catalyst, T50 and T90 of NO conversion were same trend with lower degree ca. 150 °C, the CH4 conversion of Pd/CN-M was also much better than that of Pd/CN-C. After thermal aging, the conversions of CO, NO and CH4 of Pd/CN-M had a finite shift with 20–50 °C to high temperature. It showed unique structure, smaller crystal particles, higher metal dispersion, stronger reducibility, and higher adsorbed oxygen (Oα) on Pd/CN-M catalyst in comparison to Pd/CN-C, and dispersion thermal stabilization of Pd particles on Pd/CN-M catalyst was better than that on Pd/CN-C. This work maybe provides a new method for preparing TWCs with high active for NGVs. [ABSTRACT FROM AUTHOR]

(1) Objective: This paper conducts a comparative study on the perceptual value of fabrics dyed with tea leaves and tea stems and explores the changes and differences in the Kansei image of the dyed fabrics to provide practical guidance for the product design dyed of tea leaves and tea stems based on the experimental results. (2) Methods: firstly, an effective dyeing method was selected through literature research to dye the samples. Secondly, Kansei words were collected and screened out, and the SD scale was established for a perceptual experiment. Thirdly, a factor analysis was performed on the quantified perceptual evaluation data to compare the changes in the fabric perceptual value before and after dyeing. A T-test and cluster analysis were used to study the difference between them. Finally, according to the fabric perceptual experience results, the product design was put into practice. (3) Conclusion: the perceptual value of all the fabrics dyed with Oolong tea leaves and tea stems were improved. Except for silk chiffon and Tencel, there was no significant difference between tea stems dyeing and tea leaves dyeing in other fabrics, which shows that tea stems dyeing has great perceptual value and reuse value. [ABSTRACT FROM AUTHOR]

The melanocortin 4 receptor (MC4R) plays a critical role in the long-term regulation of energy homeostasis, and mutations in the MC4R are the most common cause of monogenic obesity. However, the precise molecular and cellular mechanisms underlying the maintenance of energy balance within MC4R-expressing neurons are unknown. We recently reported that the MC4R localizes to the primary cilium, a cellular organelle that allows for partitioning of incoming cellular signals, raising the question of whether the MC4R functions in this organelle. Here, using mouse genetic approaches, we found that cilia were required specifically on MC4R-expressing neurons for the control of energy homeostasis. Moreover, these cilia were critical for pharmacological activators of the MC4R to exert an anorexigenic effect. The MC4R is expressed in multiple brain regions. Using targeted deletion of primary cilia, we found that cilia in the paraventricular nucleus of the hypothalamus (PVN) were essential to restrict food intake. MC4R activation increased adenylyl cyclase (AC) activity. As with the removal of cilia, inhibition of AC activity in the cilia of MC4R-expressing neurons of the PVN caused hyperphagia and obesity. Thus, the MC4R signaled via PVN neuron cilia to control food intake and body weight. We propose that defects in ciliary localization of the MC4R cause obesity in human inherited obesity syndromes and ciliopathies. [ABSTRACT FROM AUTHOR]