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Density functional theory (DFT) calculations were employed to theoretically explain the reaction mechanism of acetic acid hydrogenation to ethanol on Cu catalyst. The activation barriers of key elementary steps and the adsorption configurations of key intermediates involved in acetic acid hydrogenation on Cu(111) surface were investigated. The results indicated that the direct dissociation of acetic acid to acetyl (CH3COOH → CH3CO + OH) is the rate-determined step. The activation barrier of acetic acid scission to acetyl and the adsorption energy of acetic acid are two descriptors which could determine the conversion of acetic acid. The descriptors might have effects on the ethanol selectivity including: the adsorption energy of acetaldehyde and the activation barriers for O H bond formation of C2-oxygenates (CH3CO + H → CH3COH, CH3CHO + H → CH3CHOH and CH3CH2O + H → CH3CH2OH). These proposed descriptors could be used as references to design new Cu-based catalysts that have excellent catalytic performance.

Human respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections in infants and young children worldwide, yet no vaccine or effective antiviral treatment is available. To search for new anti-RSV agents, we developed a cell-based assay that measures inhibition of RSV-induced cytopathic effect (CPE) and identified cyclopiazonic acid (CPA), an intracellular calcium ATPase inhibitor as a RSV inhibitor (EC50 values 4.13 μM) by screening of natural product library. CPA inhibited the replication of RSV strains belonging to both A and B subgroups and human parainfluenza virus type 3, but not Enterovirus 71. Mechanism of action study by time-of-addition assay and minigenome assay revealed that CPA acts at the step of virus genome replication and/or transcription. Moreover, two other calcium ATPase inhibitors (Thapsigargin and BHQ) and calcium ionophores (A23187 and ionomycin), but not calcium channel blockers (nifedipine, nimodipine, and tetrandrine), also had similar effect. These results indicate that an increase in intracellular calcium concentration is detrimental to RSV replication. Thus, our findings provide a new strategy for anti-RSV therapy via increasing intracellular calcium concentration.

Adverse environmental conditions, such as cold and drought, can inhibit plant growth, development, and productivity. The isolation and characterization of stress response genes from stress-tolerant plants can provide a better understanding of the underlying adaptive mechanisms. In this study, a novel cold-regulated gene, SikCOR413PM1, was isolated from Saussurea involucrata Kar. et Kir., which is a plant that survives at the high altitudes and in the low temperatures of alpine slopes in northwestern China. SikCOR413PM1 was induced in response to cold and drought in S. involucrata, and phylogenetic analysis revealed that the gene groups with a COR gene encoding a COR413PM protein family member. Subcellular localization of a SikCOR413PM1-green fluorescent fusion protein showed that SikCOR413PM1 was localized to the plasma membrane. A transgenic tobacco (Nicotiana tabacum) system was employed to investigate the possible role of SikCOR413PM1 in cold and drought tolerance. Analyses of growth, germination and survival rates, relative water content, malondialdehyde content, relative electrolyte leakage, and maximal photochemical efficiency of photosystem II showed that transgenic tobacco plants expressing SikCOR413PM1 were more tolerant to cold and drought stresses than WT plants. SikCOR413PM1 overexpression was also accompanied by constitutive activation of NtDREB1 and NtDREB3, two cold-responsive transcription factor genes, and NtERD10A and NtERD10B, two cold-induced genes. The expression levels of downstream transcription factor genes NtDREB3, NtERD10C, NtERD10D, and NtLEA5 were also induced in SikCOR413PM1-expressing transgenic plants under drought conditions. Our results suggest that the overexpression of SikCOR413PM1 induces changes in tobacco plants, and facilitates enhanced tolerance to cold and drought stresses.

Sulfonated mesoporous carbon catalysts were synthesized using a carbonization–sulfonation method and employed to the pre-esterification of free fatty acids contained in high acid value oil. Various synthesis parameters, such as composition of carbon precursor, carbonization and sulfonation temperature, were systematically investigated. The catalysts were characterized by N2 adsorption, small angle XRD, HRTEM, FT-IR and strong acid density analysis. The results indicated that they have a high surface area, uniform pore size, large mesopore volume, high acid density and good catalytic activity. Among them, MC600-S160 exhibited a highest activity and good stability for the esterification of FFA with methanol, the FFA conversion reached 94.6% after reaction for 3 h.

Ordered mesoporous carbon (OMC) supported ferric sulfate (FS) catalysts were prepared by impregnation, and their catalytic activity for the esterification of the free fatty acids (FFAs) in waste cooking oil (WCO) with methanol was evaluated. The FS/OMC catalysts were characterized by N 2 adsorption–desorption, powder X-ray diffraction and transmission electron microscopy. The results indicated that catalysts retained the ordered mesoporous structure, and the FS was well dispersed on the surface of the OMC. The FT-IR spectrum of pyridine adsorbed on the FS/OMC catalysts showed the presence of strong Lewis acid sites on the surface of the catalysts. The FS/OMC catalysts exhibited excellent catalytic performances for FFA esterification. In addition, the process variables that influence the esterification of FFAs, such as the FS loading, the amount of catalyst, the molar ratio of methanol to FFAs, the reaction temperature and the reaction time, were investigated and optimized. The FS/OMC catalysts are reusable and maintained their original catalytic activities after six uses.

Ru catalysts supported on activated carbon (AC) were prepared by supercritical fluid deposition (SFD) with ethanol added and their catalytic performance in butanone hydrogenation was investigated. The effects of ethanol amount on Ru particle size were systematically studied. As the amount of ethanol increased, Ru mean particle sizes always decreased firstly, then increased. And the minimum mean particle size of Ru was obtained at 10 ml ethanol. The catalysts with smaller Ru mean particle size presented higher catalytic activity. These results demonstrated that the role of ethanol may not be only co-solvent but also anti-solvent and extractant during the preparation of Ru/AC.

A novel phosphorylated ordered mesoporous carbon (POMC) solid acid catalyst has been prepared by modifying mesoporous carbon with phosphoric acid, and was employed to catalyze the esterification oleic acid with methanol. The effects of the carbonization temperature on the type of phosphorus species formed, the phosphorus content and the amount of acid in the POMC were investigated. A mechanism for the phosphorylation of the ordered mesoporous carbon is proposed. The POMCs have good catalytic activity for the esterification of oleic acid and showed good reusability.

A novel carbon-based solid acid catalyst was prepared by the sulfonation of incompletely carbonized cassava stillage residue (CSR) with concentrated sulfuric acid, and employed to catalyze the esterification of methanol and free fatty acids (FFAs) in waste cooking oil (WCO). The effects of the carbonization and the sulfonation temperatures on the pore structure, acid density and catalytic activity of the CSR-derived catalysts were systematically investigated. Low temperature carbonization and high temperature sulfonation can cause the collapse of the carbon framework, while high temperature carbonization is not conducive to the attachment of SO3H groups on the surface. The catalyst showed high catalytic activity for esterification, and the acid value for WCO is reduced to below 2mg KOH/g after reaction. The activity of catalyst can be well maintained after five cycles. CSR can be considered a promising raw material for the production of a new eco-friendly solid acid catalyst.

We address the robust adaptive coordinated attitude control problem (CACP) for formation spacecraft with model and disturbance uncertainties, and with unknown constant time delays existing in the information exchanged channels. Here, spacecraft attitude is described via quaternion, and the local relative attitude is obtained in non-convex space, i.e., on the nonlinear manifold-Lie Group. Unlike in existing designs, where constant delays must be explicit and bounded, our novel laws, by injecting a nonlinear term, solve the CACP with disturbances and unknown/large constant communication delays. To overcome model uncertainties, the adaptive method is adopted. The closed-loop systems are investigated based on the Lyapunov-Krasovskii theory and Barbalat Lemma, and a spacecraft formation is conducted to demonstrate the effectiveness of theoretical results.

Hollow and solid MnO x –CeO 2 nanospheres have been successfully prepared with a supercritical anti-solvent process and used for the selective catalytic reduction of NO with NH 3 . Solid solution structures are detected for these nanospheres. The hollow MnO x –CeO 2 nanospheres have more oxygen vacancies than the solid ones. And they also present a better NO conversion in the low-temperature range of 100–200 °C. Higher surface area, better oxygen mobility and richer surface active oxygen species are responsible for the better performance of the hollow sample. Therefore, the supercritical anti-solvent preparation of the nanospheres with the hollow structure is more favorable for the low-temperature selective catalytic reduction of NO.

Glial cell line-derived neurotrophic factor (GDNF) has emerged as the most potent neuroprotective agent tested in experimental models for the treatment of Parkinson's disease (PD). However, its use is hindered by difficulties in delivery to the brain due to the presence of the blood-brain barrier (BBB). In order to circumvent this problem, we took advantage of the fact that bone marrow stem cell-derived macrophages are able to pass the BBB and home to sites of neuronal degeneration. Here, we report the development of a method for brain delivery of GDNF by genetically modified macrophages. Bone marrow stem cells were transduced ex vivo with lentivirus expressing a GDNF gene driven by a synthetic macrophage-specific promoter and then transplanted into recipient mice. Eight weeks after transplantation, the mice were injected with the neurotoxin, MPTP, for 7 days to induce dopaminergic neurodegeneration. Macrophage-mediated GDNF treatment dramatically ameliorated MPTP-induced degeneration of tyrosine hydroxylase (TH)-positive neurons of the substantia nigra and TH(+) terminals in the striatum, stimulated axon regeneration, and reversed hypoactivity in the open field test. These results indicate that macrophage-mediated GDNF delivery is a promising strategy for developing a neuroprotective therapy for PD.

The selective hydrogenation of citral was studied with various TiO2-supported monometallic and bimetallic Pd and Au catalysts and their physical mixtures in supercritical CO2 (scCO2). Significant synergistic effects appeared when active Pd species was chemically or physically mixed with less active Au species. The total rate of conversion was greatly enhanced and the selectivity to citronellal (CAL) was improved. The physical properties of those catalysts were characterized by TEM, HRTEM-EDS, XPS, and UV/Vis and their features of H2 desorption were examined by TPD. The physical and chemical characterization results were used to discuss the reasons for the unexpected synergistic effects observed. The same selective hydrogenation was also conducted in a conventional non-polar organic solvent of n-hexane to examine the roles of scCO2. The use of scCO2 was effective for accelerating the hydrogenation of citral and improving the selectivity to CAL.

In this year, Experimental Advanced Superconducting Tokamak (EAST) has undergone the first tests successfully, and the EAST distributed data system has been reliably operated in the EAST experimental campaigns. This paper gives an overview of this system. The EAST distributed data system is based on the design of, and the experiences with the HT-7 data system; it is aimed to be a distributed, real-time and scalable system. The EAST distributed data system includes control subsystem, data acquisition subsystem and data service subsystem. Control subsystem provides remote control of the all data acquisition units, full information management and state monitoring; data acquisition subsystem that provide real-time and quasi-real-time data support for long-pulse operation consists of a set of autonomous data acquisition units which support autonomous operating and remote control. Data service subsystem is responsible for storing and publishing data.

Regulation of MAPK pathways by PKC isoforms was examined in murine bone marrow-derived mast cells (BMMCs). The PKCalpha, betaI, and betaII isoforms showed the most robust activation after FcepsilonR1-mediated stimulation by anti-ovalbumin specific IgE and ovalbumin (IgE-ova). PKCalpha, betaI, and betaII were all involved in activation of JNK, MEKK2, and ERK5, with differential relative contributions of each isoform to specific MAPK pathway components. BMMCs from mice lacking MEKK2 showed reduced production (50-60%) of IL-6, IL-13, and TNF-alpha after stimulation, demonstrating MEKK2-dependent and -independent pathways for cytokine production. Cytokine production was stimulated by over-expression of PKC in cells from MEKK2-deficient and wild-type mice. Activation of ERK5 did not occur in BMMCs lacking MEKK2, indicating that MEKK2-independent cytokine production was also ERK5-independent. Since MAPK modules differentially regulate mast cell functions, including degranulation and cytokine production, it is suggested that specific functions could be targeted by inhibiting specific PKC isoforms.