Prospects of Spin Catalysis on Spin-Polarized Graphene Heterostructures

Extreme points on potential energy surfaces of Ni adatom on free-standing graphene and top:fcc and hcp:fcc graphene/ Ni(111) heterostructures in different spin states were studied using periodic boundary conditions density functional theory approach. It was found that the spin states of the substrates strongly influence the energy of the Ni adatom extreme points on potential energy surface by decreasing (top:fcc heterostructure) or increasing (hcp:fcc heterostructure) the total energies of Z1, Z1 , and Z2 Ni adatom coordinations on graphene. This phenomenon offers unique possibilities to control the potential energy surfaces of transition metal adatoms and promote surface chemical reactions using induced spin polarization of graphene substrates

Retro-aldol-type fragmentation of reducing sugars preferentially occurring in polyether at high temperature: Role of the ether oxygen as a base catalyst

The pyrolysis behavior of reducing monosaccharides was compared in the presence and absence of tetraethyleneglycol dimethylether (TEGDE), a polyether (N2/150–250 °C). The pyrolytic pathways changed drastically in TEGDE. Glucose started to decompose at >160 °C under the neat conditions, and polysaccharides, anhydrosugars (levoglucosan and 1, 6-anhydroglucofuranose), a colored substance and char were the major products. However, glucose was completely stabilized against decomposition in TEGDE and instead converted into fragmentation products including formaldehyde, glycolaldehyde, glyceraldehyde, 1, 3-dihydroxyacetone, erythrose and erythrulose at higher temperatures. The total yield of the fragmentation products reached a 74.9 wt% at 250 °C. An aldose–ketose isomerization and retro-aldol fragmentation including a six-membered cyclic transition state were suggested as the principle mechanisms. Several other polyethers gave similar results. This unique property of polyether can be explained by the basicity of the ether oxygen which acts as a proton acceptor for the hydroxyl groups in the sugar. This H-bonding between the polyether and glucose may prevent inter- and intramolecular H-bonding (H-donation to the oxygen atoms) of glucose, which results in stabilization against transglycosylation and dehydration reactions. Such inter- and intramolecular H-bonding (H-donation) may also be involved in the thermal decomposition of the melt sugar as an activation (acid catalysis) mechanism

Thermal glycosylation and degradation reactions occurring at the reducing ends of cellulose during low-temperature pyrolysis.

Thermal glycosylation and degradation reactions of cellulose (Avicel PH-101) were studied in the presence or absence of alcohols (glycerol, mannitol, 1, 2, 6-hexanetriol, 3-phenoxy-1, 2-propanediol, and 1-tetradecanol) under N(2) at 60-280°C. In the presence of glycerol (heating time, 10 min), the reducing ends were converted into glycosides when the temperature of the glycerol was >140°C without the addition of any catalysts. A temperature of 140°C is close to that required for the initiation of thermal polymerization (glycosylation). Although the conversion was only around 20% in the range of 140-180°C, the reactivity increased above 200-240°C where the thermal expansion of cellulose crystals is reported to become significant. Finally, all reducing ends were converted into glycosides at 260°C. Such heterogeneous reactivity likely arose from the lower reactivities of the reducing ends in the crystalline region due to their lower accessibility to glycerol, although the reactivity in the non-crystalline region was similar to that of glucose. Alcohols that have a lower OH/C ratio did not react with the reducing ends, suggesting that the hydrophilicity of the alcohol was critical for the glycosylation reaction to proceed. The glycosylated cellulose samples were found to be significantly stabilized against pyrolytic coloration. The results of neat cellulose pyrolysis indicated that two competitive reactions, thermal glycosylation and degradation, formed a dark-colored substance at the reducing ends while the internal glucose units in the cellulose were comparatively stable

Reducing end-group of cellulose as a reactive site for thermal discoloration

Thermal discoloration of cellulose (Avicel PH-101 and Whatman No. 42 filter paper) was studied in N2 at 160–280 °C with glycerol-treated and NaBH4-reduced samples, to understand the role of the reducing end. Thermal discoloration of glycerol-treated Avicel PH-101, in which some of the reducing ends were converted into glycosides (non-reducing ends), was suppressed compared with the original cellulose, and the level of suppression was directly related to the extent of glycosylation of the reducing ends. The stabilization efficiency of glycerol-treated Whatman No. 42 filter paper suggested that the reducing ends newly formed by reduction of the degree of polymerization (DP) (to about 200) during heat treatment contributed to the discoloration. The important role of the reducing ends in thermal discoloration was supported by the stabilization of Avicel PH-101 by reduction with NaBH4 (giving a reducing end content that was 2% of that of the original cellulose). Thermally induced discoloration was also inhibited by heating cellulose in suspension in the polyether tetraethyleneglycol dimethylether, which has been reported to inhibit the thermal degradation of reducing sugars

Prospects of Spin Catalysis on Spin-Polarized Graphene Heterostructures

Extreme points on potential energy surfaces of Ni adatom on free-standing graphene and top:fcc and hcp:fcc graphene/ Ni(111) heterostructures in different spin states were studied using periodic boundary conditions density functional theory approach. It was found that the spin states of the substrates strongly influence the energy of the Ni adatom extreme points on potential energy surface by decreasing (top:fcc heterostructure) or increasing (hcp:fcc heterostructure) the total energies of Z1, Z1 , and Z2 Ni adatom coordinations on graphene. This phenomenon offers unique possibilities to control the potential energy surfaces of transition metal adatoms and promote surface chemical reactions using induced spin polarization of graphene substrates

A randomized phase II study to assess the effect of adjuvant immunotherapy using α-GalCer-pulsed dendritic cells in the patients with completely resected stage II–IIIA non-small cell lung cancer: study protocol for a randomized controlled trial

Abstract Background As the toxicity associated with the α-GalCer-pulsed dendritic cell (DC) therapy could be considered to be negligible, its addition to postoperative adjuvant chemotherapy would be expected to greatly improve the therapeutic effect, and could result in prolonged survival. The aim of the present study is to compare the therapeutic efficacy of alpha-galactosylceramide-pulsed DC therapy in patients who have undergone a complete resection of stage II–IIIA non-small-cell lung cancer (NSCLC) followed by postoperative adjuvant therapy with cisplatin plus vinorelbine, to that in patients who did not receive additional treatment (surgical resection plus postoperative adjuvant chemotherapy only). Methods Subsequent to the complete resection of NSCLC, followed by the administration of cisplatin plus vinorelbine dual-agent combination adjuvant chemotherapy, patients who satisfy the inclusion criteria will be randomly allocated to either the α-GalCer-pulsed DC immune therapy group, or the standard treatment group. In total, 56 patients will be included in the study. The primary endpoint is recurrence-free survival, and the secondary endpoints are natural killer T-cell-specific immune response, the frequency of toxic effects and safety, and overall survival. Discussion In order to determine the efficacy of α-GalCer-pulsed DC therapy, the present study compares patients with stage II–III NSCLC who underwent complete surgical resection followed by postoperative adjuvant therapy with cisplatin plus vinorelbine, to those who did not receive additional treatment (surgical resection plus postoperative adjuvant chemotherapy only). Trial registration UMIN000010386 ( R000012145 ). Registered on 1 April 2013. UMIN-CTR is officially recognized as a registration site which satisfies ICMJE criteria

Additional file 1: of A randomized phase II study to assess the effect of adjuvant immunotherapy using α-GalCer-pulsed dendritic cells in the patients with completely resected stage II–IIIA non-small cell lung cancer: study protocol for a randomized controlled trial

SPIRIT 2013 Checklist: recommended items to address in a clinical trial protocol and related documents*. (DOC 123 kb