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Structural models of N 2 O and NO 2 adsorption on transition metal-TiO 2 surface (M=Fe, Cu or Mn). [Display omitted] • Adsorption effect of NO 2 and N 2 O on transition metal modified TiO 2 (1 0 1) surface was studied with 8 models. • Adsorption of NO 2 /N 2 O on Mn is more stable than that on Cu, and the adsorption of N 2 O on Fe is more stable. • O atom of NO 2 /N 2 O adsorbed on Mn- and Fe-TiO 2 (1 0 1) catalyst is more likely to participate in the redox reaction. The geometric structure and electronic properties of transition metal M (M = Cu, Fe, Mn)-TiO 2 (1 0 1) surface adsorbed by NO 2 and N 2 O were calculated by density functional theory (DFT) and DFT + U theory. Eight models were established to explore the effect of NO 2 and N 2 O adsorption, and the results show that transition metal adsorption has different effects on the redox reaction of NO 2 and N 2 O. From the stability of adsorption structure, the adsorption of NO 2 /N 2 O on Mn atom is more stable, and the adsorption of N 2 O on Fe atom is more stable than that of NO 2. The analysis of charge transfer and electronic structure show that a large number of free active electrons are formed around the Mn and Fe atoms, which are connected with the N atoms of NO 2 /N 2 O, and one N atom in N 2 O changes from losing electrons to gaining a small number of electrons. This means that the Mn and Fe atoms can stimulate more active electrons to exchange with NO 2 and N 2 O, that is, they can exchange more electrons with NO 2 /N 2 O before selective catalytic reduction (SCR) reaction, which is beneficial to the succeeding catalytic reaction. [ABSTRACT FROM AUTHOR]

To study the effect of different kinds of transition metals and their proportions on NO adsorption on TiO 2 surface, the density functional theory (DFT) method was used to calculate the energetic, geometric structure and electronic structure of the adsorption of NO on transition metal M (M = Cu, Fe and Mn)-anatase TiO 2 (101) surface. The above transition metals were adsorbed on anatase TiO 2 (101) surface in three different adsorption ratios, which are single transition metal adsorption model, mixed 2:2 and 1:3 ratio models. On the basis of the study, 13 models were established to study the effects of transition metals and adsorption ratio on NO oxidation to determine the optimal adsorption model. It has been found from the energetic calculations that mixed adsorption model is more stable for the adsorption of NO. The results of electronic structure and charge distribution analysis showed that a large quantity of active electron clusters are distributed around Mn and Fe atoms, which are attached to a large area of N atoms in NO, indicating that Mn and Fe can provide more electrons for catalytic reaction and facilitate electron exchange between catalyst and NO. Among all the adsorption models, the 3Fe+1Mn–TiO 2 and 3Mn+1Fe–TiO 2 models are superior, i.e., they can exchange more electrons with NO before the catalytic reaction, which is conducive to the subsequent catalytic reaction. [ABSTRACT FROM AUTHOR]

In this work, birch bark (BB) was used for the first time to prepare porous biochars via different one-step methods including direct activation (BBB) and N-doping co-activation (N-BBB). The specific surface area and total pore volume of BBB and N-BBB were 2502.3 and 2292.7 m2/g, and 1.1389 and 1.0356 cm3/g, respectively. When removing synthetic methyl orange (MO) dye and heavy metal Cr6+, both BBB and N-BBB showed excellent treatment ability. The maximum adsorption capacities of BBB and N-BBB were 836.9 and 858.3 mg/g for MO, and 141.1 and 169.1 mg/g for Cr6+, respectively, which were higher than most previously reported biochar adsorbents. The probable adsorption mechanisms, including pore filling, π–π interaction, H-bond interaction, and electrostatic attraction, supported the biochars' demonstrated high performance. In addition, after five recycles, the removal rates remained above 80%, which showed the high stability of the biochars. This work verified the feasibility of the one-step N-doping co-activation method to prepare high-performance biochars, and two kinds of biochars with excellent performance (BBB and N-BBB) were prepared. More importantly, this method provides new directions and ideas for the development and utilization of other biomasses. [ABSTRACT FROM AUTHOR]

Life history and reproductive traits of a submerged aquatic weed, Ottelia alismoides (L.) Pers., were studied in irrigation ponds in southwestern Japan. In addition, growth and seed production were investigated in relation to nutrient condition and water depth. The size of plants was very variable but reproductive allocation was nearly constant irrespective of the plant size at reproductive stage, amounting to more than 30% at maximum. Bagging experiments confirmed autogamy of the species. Ottelia alismoides grew best in nutrient-rich water with mud substratum. The optimal water depth for the growth of the species was approximately 50 cm compared with 20 and 90 cm. However, the reproductive allocation and seed set rate did not change much in different nutrient and water depth conditions. The seeds were produced by cleistogamous flowers in a depth of 90 cm. Morphological and ecological plasticity revealed in the present study was considered to be adapted to unstable environments such as rice fields and irrigation ponds liable to water-level fluctuation. The conditions required for the restoration of the populations of O. alismoides are discussed based on the present results. [ABSTRACT FROM AUTHOR]

Ecological life history and reproductive traits of two threatened aquatic macrophytes, Blyxa aubertii L.C. Richard and B. echinosperma (Clarke) Hooker, were studied in irrigation ponds in south-western Japan. The size of plants varied greatly in both species but reproductive allocation was nearly constant irrespective of plant size at reproductive stage, amounting to 31.8% and 45.9% at maximum in B. aubertii and B. echinosperma, respectively. The number of flowers and total number of seeds produced per individual were associated significantly with plant size. Seeds were produced by self-pollination both in emerged and submerged cleistogamous flowers and seed set rate of the two species was very high. These traits are considered to be adaptive to unstable environments that are liable to water level fluctuations, such as rice-fields and irrigation ponds. [ABSTRACT FROM AUTHOR]

The extent of red blood cell fragmentation in peripheral blood is useful for diagnosis and follow-up in many diseases, e.g. haemolytic uremic syndrome, transplantation-associated thrombotic microangiopathy (BMT-TMA). However, this quantification still relies on manual counting of fragmented red cells on blood smears. We have developed a quantification system by gating a fixed area of fragmented red blood cells (Gate 1) on an automated haematology analyser (XE-2100, Sysmex Co., Kobe, Japan). The fragmented red cell percentage (FRC%) calculated with this system, from 100 samples, was highly correlated with the manual count (r=0.902, P < 0.0001). Because microcytic anaemia specimens usually occupy a lower position on the XE-2100 scattergram, with microcytic cells overlapping Gate 1 and causing a spuriously high FRC% calculation, a supplementary gate (Gate 2) was added. Using the particle number in this gate as well as in Gate 1, a revised method for such samples was developed and its validity confirmed (revised FRC% correlated with a manual count for 10 subjects (P < 0.001). Because this gating system can be programmed on any XE-2100, it is likely to prove useful for accurate quantification of red blood cell fragmentation and for the monitoring of the development of BMT-TMA. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO 2) is widely used as a catalyst due to its high redox activity. To explore the metal oxide-TiO 2 supported interactions and their effects, the electronic structure, adsorption energies and physical properties of different metal oxides (FeO, CuO and MnO) adsorbed anatase TiO 2 (101) surface have been studied by means of density functional theory (DFT) calculations, compared with that on pure TiO 2 surface. On the basis of the study, three different kinds of adsorption ratio among the metal oxides mentioned above (single metal oxide adsorption model, different metal oxide adsorption models with 2:2 ratio and 1:3 ratio), as a whole, 12 models were investigated to study the influence of different proportion of metal oxide adsorbed in the TiO 2 carrier in order to find the best metal oxide adsorption ratio. The calculated results show that the different adsorption ratios of metal oxides have influences on the reactivity of catalysts. A small amount of CuO will increase the reactivity of the catalyst, but the overall catalytic effect of the catalyst containing CuO is not comparable to those only containing FeO or MnO. In terms of the structural stability of catalysts, the catalysts containing FeO are more stable than those only containing CuO and MnO, and the more FeO adsorption ratio, the more stable the catalyst structure will be. The results of binding energy and bandgap show that the structure of the 1:3 adsorption model is more stable than the other two models, and the mixed adsorption leads to the reduction of bandgap. The order of influence is 1:3 ratio adsorption model >2:2 ratio adsorption model > single metal oxide adsorption model. Electron local density function (ELF) of transition metal oxide catalyst models.(The red represents the ELF value = 1, the green represents the ELF value = 0.5, and the blue represents the ELF value = 0.). Image 1 • The adsorption effect of metal oxide-TiO 2 catalyst was studied by 12 models. • A small amount of CuO will increase the reactivity of the catalyst. • The higher the FeO adsorption rate, the more stable the catalyst structure. [ABSTRACT FROM AUTHOR]

Distracted driving due to smartphone use is one of the key reasons for road accidents. However, the 6G super-heterogeneous network systems and highly differentiated application scenarios require highly elastic and endogenous information services involving the use of smart apps, and related information retrieval by drivers in modern Vehicle-to-People (V2P) Networks. The tension raised due to the conflicting attention requirements of driving and information retrieval can be resolved by designing information retrieval solutions that demand minimal user interaction. In this paper, we construct a Personalized Search Query Generator (PSQG) to reduce driver-mobile interaction during information retrieval in the 6 G era. This system has a query generator and a query recommendation component that update two sets of relationships dynamically: one is the query and the title, another is search and recommendation. The proposed system learns a user's intent based on historical query records and recommends personalized queries, thus reducing the driver-mobile interaction time. We deploy the system into a real search engine and conduct several online experiments. These experiments are conducted using a custom constructed dataset comprising ten million samples. We use the BLEU-score metric and perform A/B testing. The results demonstrate that our system can assist users in making precise queries efficiently. The proposed system can improve drivers’ safety if used in smartphones and other information retrieval systems in vehicles. [ABSTRACT FROM AUTHOR]

The glycosylation levels of proteins in cancer cells are closely related to cancer invasion and migration. CD44 is a transmembrane glycoprotein that is significantly overexpressed in a variety of tumor cells and has been proven to promote the migration and motility of cancer cells, but the effect of its N-glycosylation modification on CD44 protein function in tumors is less studied. Here, we investigated the effect of six N-glycan chains (N25/57/100/110/120/255) on CD44s localization, function and stability in hepatocarcinoma cells. When the six sites were mutated, we found that CD44s lost its membrane localization in Huh7 and MHCC-97H cells. On this basis, we identified three glycosylation sites on CD44s (N57, N100 and N110) that played key roles in intracellular localization. When N57, N100 and N110 were mutated together, CD44 localized to the cytoplasm, while another three-site mutant (N25/N120/N255) was still anchored to the membrane. In addition, the ability of CD44-N57Q/N100Q/N110Q to promote the metastasis and invasion of Huh7 and 97H cells was weakened compared with that of CD44-N25Q/N120Q/N255Q. Furthermore, CD44-N57Q/N100Q/N110Q accumulated abnormally in the ER, and a high level of the ER stress (ERS) marker BiP was detected at the same time compared with wild-type CD44. When the lysosome inhibitor CQ was added, the content of mutant protein that triggered ERS significantly increased, which indicated that the degradation mode of CD44-N57Q/N100Q/N110Q after ERS was mainly through the lysosomal pathway (ERLAD). The results revealed that the N-glycosylation sites N57, N100 and N110 mutated on CD44s affected its function and degraded it by lysosomes after triggering ERS. These findings provide data for new studies on ER-related degradation, further promote the study of the glycan chain function of CD44 and furnish new ideas for the treatment of liver cancer metastasis. • N57, N100 and N110 are crucial N-glycosylation sites for CD44 function of promoting metastasis in HCC. • The lack of glycan chains on N57, N100 and N110 leads to translocation from membrane to cytoplasm of CD44 in HCC cells. • CD44-N57Q/N100Q/N110Q is degraded through ERLAD after triggering ER stress. [ABSTRACT FROM AUTHOR]

N -glycosylation has been revealed to be tightly associated with cancer metastasis. As a key transferase that catalyzes the formation of β1,4 N -acetylglucosamine (β1,4GlcNAc) branches on the mannose core of N -glycans, N -acetylglucosaminyltransferase IVa (GnT-IVa) has been reported to be involved in hepatocellular carcinoma (HCC) metastasis by forming N -glycans; however, the underlying mechanisms are largely unknown. In the current study, we found that GnT-IVa was upregulated in HCC tissues and positively correlated with worse outcomes in HCC patients. We found that GnT-IVa could promote tumor growth in mice; notably, this effect was attenuated after mutating the enzymatic site (D445A) of GnT-IVa, suggesting that GnT-IVa regulated HCC progression by forming β1,4GlcNAc branches. To mechanistically investigate the role of GnT-IVa in HCC, we conducted GSEA and GO functional analysis as well as in vitro experiments. The results showed that GnT-IVa could enhance HCC cell migration, invasion and adhesion ability and increase β1,4GlcNAc branch glycans on integrin β1 (ITGB1), a tumor-associated glycoprotein that is closely involved in cell motility by interacting with vimentin. Interruption of β1,4GlcNAc branch glycan modification on ITGB1 could suppress the interaction of ITGB1 with vimentin and inhibit cell motility. These results revealed that GnT-IVa could promote HCC cell motility by affecting the biological functions of ITGB1 through N -glycosylation. In summary, our results revealed that GnT-IVa is highly expressed in HCC and can form β1,4GlcNAc branches on ITGB1, which are essential for interactions with vimentin to promote HCC cell motility. These findings not only proposed a novel mechanism for GnT-IVa in HCC progression but also revealed the significance of N -glycosylation on ITGB1 during the process, which may provide a novel target for future HCC therapy. • GnT-IVa enhances cell motility and correlates with poor outcomes of HCC. • GnT-IVa increases β1,4GlcNAc branches on ITGB1 to promote cell motility of HCC. • β1,4GlcNAc branches on ITGB1 affect interactions with vimentin in HCC. [ABSTRACT FROM AUTHOR]