Water-assisted hydrogen spillover in Pt nanoparticle-based metal-organic framework composites.

Hydrogen spillover is the migration of activated hydrogen atoms from a metal particle onto the surface of catalyst support, which has made significant progress in heterogeneous catalysis. The phenomenon has been well researched on oxide supports, yet its occurrence, detection method and mechanism on non-oxide supports such as metal-organic frameworks (MOFs) remain controversial. Herein, we develop a facile strategy for efficiency enhancement of hydrogen spillover on various MOFs with the aid of water molecules. By encapsulating platinum (Pt) nanoparticles in MOF-801 for activating hydrogen and hydrogenation of C=C in the MOF ligand as activated hydrogen detector, a research platform is built with Pt@MOF-801 to measure the hydrogenation region for quantifying the efficiency and spatial extent of hydrogen spillover. A water-assisted hydrogen spillover path is found with lower migration energy barrier than the traditional spillover path via ligand. The synergy of the two paths explains a significant boost of hydrogen spillover in MOF-801 from imperceptible existence to spanning at least 100-nm-diameter region. Moreover, such strategy shows universality in different MOF and covalent organic framework materials for efficiency promotion of hydrogen spillover and improvement of catalytic activity and antitoxicity, opening up new horizons for catalyst design in porous crystalline materials.

Amorphous Chromium Oxide with Hollow Morphology for Nitrogen Electrochemical Reduction under Ambient Conditions.

The electrocatalytic nitrogen reduction reaction (NRR), an alternative method of nitrogen fixation and conversion under ambient conditions, represents a promising strategy for tackling the energy-intensive issue. The design of high-performance electrocatalysts is one of the key issues to realizing the application of NRR, but most of the current catalysts rely on the use of crystalline materials, and shortcomings such as a limited number of catalytic active sites and sluggish reaction kinetics arise. Herein, an amorphous metal oxide catalyst H-CrOx/C-550 with hierarchically porous structure is constructed, which shows superior electrocatalytic performance toward NRR under ambient conditions (yield of 19.10 µg h-1 mgcat-1 and Faradaic efficiency of 1.4% at -0.7 V vs a reversible hydrogen electrode, higher than that of crystalline Cr2O3 and solid counterparts). Notably, the amorphous metal oxide obtained by controlled pyrolysis of metal-organic frameworks (MOFs) possess abundant unsaturated catalytic sites and optimized conductivity due to the controllable degree of metal-oxygen bond reconstruction and the doping of carbon materials derived from organic ligands. This work demonstrates MOF-derived porous amorphous materials as a viable alternative to current electrocatalysts for NH3 synthesis at ambient conditions.

Fast 3D Indoor Scene Synthesis by Learning Spatial Relation Priors of Objects.

We present a framework for fast synthesizing indoor scenes, given a room geometry and a list of objects with learnt priors. Unlike existing data-driven solutions, which often learn priors by co-occurrence analysis and statistical model fitting, our method measures the strengths of spatial relations by tests for complete spatial randomness (CSR), and learns discrete priors based on samples with the ability to accurately represent exact layout patterns. With the learnt priors, our method achieves both acceleration and plausibility by partitioning the input objects into disjoint groups, followed by layout optimization using position-based dynamics (PBD) based on the Hausdorff metric. Experiments show that our framework is capable of measuring more reasonable relations among objects and simultaneously generating varied arrangements in seconds compared with the state-of-the-art works.

The molecular characterization and immune protection of adhesion protein 65 (AP65) of Trichomonas vaginalis.

BACKGROUND: Adherence to the surface of the host cell is the precondition for T. vaginalis parasitism and pathogenicity, causing urogenital infection. The AP65 of T. vaginalis (TvAP65) involves in the process of adhesion. So, the present study was aimed at investigating the molecular characterization and vaccine candidacy of TvAP65 for protecting the host from the onset of Trichomoniasis. METHODS: The open reading frame (ORF) of TvAP65 was amplified and then inserted into pET-32a (+) to clone recombinant TvAP65 (rTvAP65). The immunoblotting determined the immunogenicity and molecular size of TvAP65, while immunofluorescence staining visualized and the precise localization of TvAP65 in T. vaginalis trophozoites. Animal challenge and enzyme-linked immunosorbent assay (ELISA) test were used to evaluate the immunoprotection and the types of the immune response of TvAP65. RESULTS: By the sequence analysis, TvAP65 encoded a 63.13 kDa protein that consisted 567 amino acid residues with a high antigenic index. The western blotting revealed that rTvAP65 and native TvAP65 could interact with the antibodies in the rat serums post hoc rTvAP65 immunization and the serums from the mice that were experimentally infected with T. vaginalis, respectively. Immunofluorescence stained TvAP65 on the surface of T. vaginalis trophozoites. Moreover, following emulsification with Freund's adjuvant, rTvAP65 was subsequently administered to BALB/c mice three times at 0, 2, and 4 weeks and the results from this animal challenge experiments showed significant increases in immunoglobulins of IgG2a, IgG1, and IgG, and cytokine of IFN-γ, and IL-2, and 10. Lastly, rTvAP65 vaccinated animals had a prolonged survival time (26.80 ± 4.05) after challenged by T. vaginalis. CONCLUSIONS: TvAP65 mediated the adhesion of T. vaginalis to the host epithelia for the pathogenesis of the parasite and can be considered as a candidate protein for designing a functional vaccine that induces cell-mediated and humoral immunity against the T. vaginalis infection.

Wearable Textile UHF-RFID Sensors: A Systematic Review.

Textile radio-frequency identification operating in ultra-high frequency (UHF-RFID) sensors based on different scenarios are becoming attractive with the forthcoming internet of things (IoT) era and aging society. Compared with conventional UHF-RFID sensors, textile UHF-RFID sensors offer the common textile features, light weight, washability and comfort. Due to the short time and low level of development, researches on the integration of textile UHF-RFID techniques and textile sensing techniques are not flourishing. This paper is motivated by this situation to identify the current research status. In this paper, we provide a systematic review of the fundamentals of textile UHF-RFID sensors techniques, materials, the brief history and the state-of-the-art of the scenario-based development through detailed summary and analysis on the achievements from the starting year of 2004 to the present time. Moreover, according to the analysis, we give a proposal of the future prospects in several aspects, including the new materials and manufacturing processes, machine learning technology, scenario-based applications and unavoidable reliability.

Development of a convenient detection method for Trichomonas vaginalis based on loop-mediated isothermal amplification targeting adhesion protein 65.

BACKGROUND: Trichomoniasis resulting from Trichomonas vaginalis (T. vaginalis) has been considered as a commonly seen disease with the transmission way of sex. At present, the detection methods of T. vaginalis mainly include wet mount microscopy, culture, PCR, immunofluorescence and ELISA. However, all of these detection methods exist shortcomings. METHODS: In this study, a loop-mediated isothermal amplification (LAMP) assay that targeted the species-specific sequence of adhesion protein 65 (AP65) gene had been conducted to detect T. vaginalis. The optimum reaction system and conditions were optimized in this rapid detection method. RESULTS: The results of sensitivity analysis showed that the LAMP assay targeting the AP65 gene was 1000 times more sensitive than the nested PCR targeting the actin gene commonly used for detection of T. vaginalis, and the detecting limitation of the former was 10 trichomonad. Moreover, the amplification of the target gene AP65 by LAMP assay exhibited high specificity and the product was exclusively from T. vaginalis. The detection technique of LAMP did not exhibit cross-reactivity with the common pathogens of Trichinella spiralis, Toxoplasma gondii, Escherichia coli, Candida albicans, Staphylococcus aureus, Haemophilus. CONCLUSIONS: According to the present study, the LAMP assay with the target of AP65 gene, was suitable for the early diagnosis of T. vaginalis infections. Consequently, the LAMP assay was proposed by the current study as a point-of-care examination and an alternative molecular tool which exhibited the potential value in the treatment, control and prevention of trichomoniasis transmission and relevant complication.