Supported monodisperse Pt nanoparticles from [Pt-3(CO)(3)(mu(2)-CO)(3)](5)(2-) clusters for investigating support-Pt interface effect in catalysis

MOST of China [2011CB932403]; NSFC [21131005, 21021061, 20925103, 20923004]; Fok Ying Tung Education Foundation [121011]Here we present a surfactant-free strategy to prepare supported monodisperse Pt nanoparticles from molecular [Pt-3(CO)(3)(mu(2)-CO)(3)](5)(2-) clusters. The strategy allows facile deposition of same-sized Pt nanoparticles on various oxide supports to unambiguously study the interface effect between noble metal and metal oxide in catalysis. In this study, Fe2O3 is demonstrated to be a superior support over TiO2, CeO2 and SiO2 to prepare highly active supported Pt nanoparticles for CO oxidation, which indicates that the interfaces between Pt and iron oxide are the active sites for O-2 activation and CO oxidation

Electrostatic Self-Assembling Formation of Pd Superlattice Nanowires from Surfactant-Free Ultrathin Pd Nanosheets

A facile method has been developed for face-to-face assembly of two-dimensional surfactant-free Pd nanosheets into one-dimensional Pd superlattice nanowires. The length of the Pd nanowires can be well controlled by introducing cations of different concentration and charge density. Our studies reveal that cations with higher charge density have stronger charge-screening ability, and their introduction leads to more positive zeta-potential and decreased electrostatic repulsion between negatively charged Pd nanosheets. Moreover, their surfactant-free feature is of great importance in assembling the Pd nanosheets into superlattice nanowires. While the cations are important for the assembly of Pd nanosheets, the use of poly(vinylpyrrolidone) is necessary to enhance the stability of the assembled superlattice nanowires. The as-assembled segmented Pd nanowires display tunable surface plasmon resonance features and excellent hydrogen-sensing properties.MOST of China 2011CB932403 2014CB932004 NSFC 21131005 21333008 21420102001 NFFTBS J131002

Ligand-Stabilized Au13Cux (x=2, 4, 8) Bimetallic Nanoclusters: Ligand Engineering to Control the Exposure of Metal Sites

通讯作者地址: Zheng, NF (通讯作者) Xiamen Univ, Collaborat Innovat Ctr Chem Energy Mat, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China.Three novel bimetallic Au-Cu nanoclusters stabilized by a mixed layer of thiolate and phosphine ligands bearing pyridyl groups are synthesized and fully characterized by X-ray single crystal analysis and density functional theory computations. The three clusters have an icosahedral Au-13 core face-capped by two, four, and eight Cu atoms, respectively. All face-capping Cu atoms in the clusters are triply coordinated by thiolate or pyridyl groups. The surface ligands control the exposure of Au sites in the clusters. In the case of the Au13Cu8 cluster, the presence of 12 2-pyridylthiolate ligands still leaves open space for catalysis. All the 3 clusters are 8-electron superatoms displaying optical gaps of 1.8-1.9 eV. The thermal decomposition studies suggest that the selective release of organic ligands from the clusters is possible.MOST of China 2011CB932403 ,2011CB201301 ,2009CB930703 , NSFC 21227001 ,21131005 ,21021061 ,20925103 ,20923004 , Fundamental Research Funds for the Central Universities 201012104

The metabolomic plasma profile of patients with Duchenne muscular dystrophy: providing new evidence for its pathogenesis

Abstract Background Duchenne muscular dystrophy (DMD) is a fatal genetic muscle-wasting disease that affects 1 in 5000 male births with no current cure. Despite great progress has been made in the research of DMD, its underlying pathological mechanism based on the metabolomics is still worthy of further study. Therefore, it is necessary to gain a deeper understanding of the mechanisms or pathogenesis underlying DMD, which may reveal potential therapeutic targets and/or biomarkers. Results Plasma samples from 42 patients with DMD from a natural history study and 40 age-matched healthy volunteers were subjected to a liquid chromatography-mass spectrometry-based non-targeted metabolomics approach. Acquired metabolic data were evaluated by principal component analysis, partial least squares-discriminant analysis, and metabolic pathway analysis to explore distinctive metabolic patterns in patients with DMD. Differentially expressed metabolites were identified using publicly available and integrated databases. By comparing the DMD and healthy control groups, 25 differential metabolites were detected, including amino acids, unsaturated fatty acids, carnitine, lipids, and metabolites related to the gut microbiota. Correspondingly, linoleic acid metabolism, D-glutamine and D-glutamate metabolism, glycerophospholipid metabolism, and alanine, aspartate, and glutamate metabolism were significantly altered in patients with DMD, compared with those of healthy volunteers. Conclusions Our study demonstrated the abnormal metabolism of amino acids, energy, and lipids in patients with DMD, consistent with pathological features, such as recurrent muscle necrosis and regeneration, interstitial fibrosis, and fat replacement. Additionally, we found that metabolites of intestinal flora were disordered in DMD patients, providing support for treatment of intestinal microbia disturbance in DMD diseases. Our study provides a new research strategy for understanding the pathogenesis of DMD

Act as what you think : towards personalized EEG interaction through attentional and embedded LSTM learning

The “mind-controlling” capability has always been in mankind's fantasy. With the recent advancements in electroencephalograph (EEG) techniques, brain-computer interface (BCI) researchers have explored some solutions to allow individuals to perform various tasks using their minds. However, the commercial off-the-shelf devices to run accurate EEG signal collection are usually expensive and the comparably cheaper devices can only present coarse results, which prevents the practical application of these devices in domestic services. To tackle this challenge, we propose and develop an end-to-end solution that enables fine brain-robot interaction (BRI) through embedded learning of coarse EEG signals from low-cost devices, namely PerBCI, so that people having difficulty moving, such as the elderly, can mind command and control a robot to perform some basic household tasks. Our contributions are three folds: 1) We present a stacked long short-term memory (BiLSTM) structure, along with specific pre-processing techniques to handle the time-dependency of EEG signals and their classification. 2) We propose a personalized design to adaptively capture multiple features and achieve accurate recognition of individual EEG signals by enhancing the signal interpretation of BiLSTM with an attention mechanism. 3) We develop a low-cost, real-time and end-to-end BRI system that can run our PerBCI models and algorithms in the embedded robot platform to perform more than one type of domestic task based on the users' EEG signal inputs. Our real-world experiments with elderly participants of diverse backgrounds in a home setting and system comparison with other approaches show that the proposed end-to-end solution with low cost can achieve satisfactory run-time speed, accuracy and energy-efficiency

Supported monodisperse Pt nanoparticles from [Pt3(CO) 3(μ2-CO)3]52- clusters for investigating support-Pt interface effect in catalysis

Here we present a surfactant-free strategy to prepare supported monodisperse Pt nanoparticles from molecular [Pt3(CO) 3(μ2-CO)3]52- clusters. The strategy allows facile deposition of same-sized Pt nanoparticles on various oxide supports to unambiguously study the interface effect between noble metal and metal oxide in catalysis. In this study, Fe2O 3 is demonstrated to be a superior support over TiO2, CeO2 and SiO2 to prepare highly active supported Pt nanoparticles for CO oxidation, which indicates that the interfaces between Pt and iron oxide are the active sites for O2 activation and CO oxidation. ? 2013 The Royal Society of Chemistry

A Conserved Glycine Is Identified to be Essential for Desaturase Activity of IpFAD2s by Analyzing Natural Variants from <i>Idesia polycarpa</i>

High amounts of polyunsaturated fatty acids (PUFAs) in vegetable oil are not desirable for biodiesel or food oil due to their lower oxidative stability. The oil from Idesia polycarpa fruit contains 65&#8315;80% (mol%) linoleic acid (C18:2). Therefore, development of Idesia polycarpa cultivars with low PUFAs is highly desirable for Idesia polycarpa oil quality. Fatty acid desaturase 2 (FAD2) is the key enzyme converting oleic acid (C18:1) to C18:2. We isolated four FAD2 homologs from the fruit of Idesia polycarpa. Yeast transformed with IpFAD2-1, IpFAD2-2 and IpFAD2-3 can generate appreciable amounts of hexadecadienoic acid (C16:2) and C18:2, which are not present in wild-type yeast cells, revealing that the proteins encoded by these genes have &#916;12 desaturase activity. Only trace amounts of C18:2 and little C16:2 were detected in yeast cells transformed with IpFAD2-4, suggesting IpFAD2-4 displays low activity. We also analyzed the activity of several FAD2 natural variants of Idesia polycarpa in yeast and found that a highly conserved Gly376 substitution caused the markedly reduced products catalyzed by IpFAD2-3. This glycine is also essential for the activity of IpFAD2-1 and IpFAD2-2, but its replacement in other plant FAD2 proteins displays different effects on the desaturase activity, suggesting its distinct roles across plant FAD2s proteins

Apoptotic and nonapoptotic function of caspase 7 in spermatogenesis

Recent studies have reported that caspase 7 has an apoptotic and nonapoptotic function. However, the relationship between caspase 7 and spermatogenesis remains unknown. This study aimed to investigate the possible function of caspase 7 during normal and abnormal spermatogenesis. The cleaved form of caspase 7 was detected in testis tissues at different postpartum times (5-14 weeks) by qRT-PCR, Western blot and immunohistochemistry (IHC). Then, the mice models of spermatogenic dysfunction were obtained by busulfan (30 mg kg−1 to further evaluate the potential function and mechanism of caspase 7. qRT-PCR and Western blot results showed that caspase 7 expression was gradually elevated from 5 to 14 weeks, which was not connected with apoptosis. IHC results revealed that caspase 7 was mainly located in spermatogenic cells and Leydig cells. In addition, spermatogenic dysfunction induced by busulfan gradually enhanced the apoptosis and elevated the expression of caspase 3, caspase 6, and caspase 9, but decreased the expression of caspase 7 in spermatogenic cells. However, when spermatogenic cells were mostly disappeared at the fourth week after busulfan treatment, caspase 7 expression in Leydig cells was significantly increased and positively correlated with the expression of caspase 3, caspase 6, and caspase 9. Therefore, these results indicate that caspase 7 has a nonapoptic function that participates in normal spermatogenesis, but also displays apoptotic function in spermatogenic dysfunction