Metabolizable energy requirement for maintenance estimated by regression analysis of body weight gain or metabolizable energy intake in growing pigs

Objective: Feed energy required for pigs is first prioritized to meet maintenance costs. Additional energy intake in excess of the energy requirement for maintenance is retained as protein and fat in the body, leading to weight gain. The objective of this study was to estimate the metabolizable energy requirements for maintenance (MEm) by regressing body weight (BW) gain against metabolizable energy intake (MEI) in growing pigs.Methods: Thirty-six growing pigs (26.3 +/- 1.7 kg) were allotted to 1 of 6 treatments with 6 replicates per treatment in a randomized complete block design. Treatments were 6 feeding levels which were calculated as 50%, 60%, 70%, 80%, 90%, or 100% of the estimated ad libitum MEI (2,400 kJ/kg BW0.60 d). All pigs were individually housed in metabolism crates for 30 d and weighed every 5 d. Moreover, each pig from each treatment was placed in the open-circuit respiration chambers to measure heat production (HP) and energy retained as protein (REp) and fat (REf) every 5 d. Serum biochemical parameters of pigs were analyzed at the end of the experiment.Results: The average daily gain (ADG) and HP as well as the REp and REf linearly increased with increasing feed intake (p< 0.010). beta-hydroxybutyrate concentration of serum tended to increase with increasing feed intake (p = 0.080). The regression equations of MEI on ADG were MEI, kJ/kg BW0.60 d = 1.88xADG, g/d+782 (R-2 = 0.86) and MEm was estimated at 782 kJ/kg BW0.60 d. Protein retention of growing pigs would be positive while REf would be negative at this feeding level via regression equations of REp and REf on MEI.Conclusion: The MEm was estimated at 782 kJ/kg BW0.60 d in current experiment. Furthermore, growing pigs will deposit protein and oxidize fat if provided feed at the estimated maintenance level

Catalytic Hydrolysis of Ammonia Borane by Cobalt Nickel Nanoparticles Supported on Reduced Graphene Oxide for Hydrogen Generation

Well dispersed magnetically recyclable bimetallic CoNi nanoparticles (NPs) supported on the reduced graphene oxide (RGO) were synthesized by one-step in situ coreduction of aqueous solution of cobalt(II) chloride, nickel (II) chloride, and graphite oxide (GO) with ammonia borane (AB) as the reducing agent under ambient condition. The CoNi/RGO NPs exhibits excellent catalytic activity with a total turnover frequency (TOF) value of 19.54 mol H2 mol catalyst−1 min−1 and a low activation energy value of 39.89 kJ mol−1 at room temperature. Additionally, the RGO supported CoNi NPs exhibit much higher catalytic activity than the monometallic and RGO-free CoNi counterparts. Moreover, the as-prepared catalysts exert satisfying durable stability and magnetically recyclability for the hydrolytic dehydrogenation of AB, which make the practical reusing application of the catalysts more convenient. The usage of the low-cost, easy-getting catalyst to realize the production of hydrogen under mild condition gives more confidence for the application of ammonia borane as a hydrogen storage material. Hence, this general method indicates that AB can be used as both a potential hydrogen storage material and an efficient reducing agent, and can be easily extended to facile preparation of other RGO-based metallic systems

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Ultrafine Ni–Pt Alloy Nanoparticles Grown on Graphene as Highly Efficient Catalyst for Complete Hydrogen Generation from Hydrazine Borane

Ultrafine Ni–Pt alloy NPs grown on graphene (NiPt/graphene) have been facilely prepared via a simple one-step coreduction synthetic route and characterized by transmission electron microscopy, energy-dispresive X-ray spectroscopy, X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, X-ray photoelectron spectroscopy, Raman and Fourier transform infrared methods. The characterized results showed that ultrafine Ni–Pt NPs with a small size of around 2.3 nm were monodispersed on the graphene nanosheet. Compared to the pure Ni_0.9Pt_0.1 alloy NPs, graphene supported Ni_0.9Pt_0.1 alloy NPs exhibited much higher activity and hydrogen selectivity (100%) toward conversion of hydrazine borane (HB) to hydrogen. It is first found that the durability of the catalyst can be greatly enhanced by the addition of an excess amount of NaOH in this reaction, because of the neutralization of NaOH by the byproduct H₃BO₃ produced from the hydrolysis of HB. After six cycles of the catalytic reaction, no appreciable decrease in activity was observed, indicating that the Ni_0.9Pt_0.1/graphene catalysts have good durability/stability

Nanocatalysts for Hydrogen Generation from Ammonia Borane and Hydrazine Borane

Ammonia borane (denoted as AB, NH3BH3) and hydrazine borane (denoted as HB, N2H4BH3), having hydrogen content as high as 19.6 wt% and 15.4 wt%, respectively, have been considered as promising hydrogen storage materials. Particularly, the AB and HB hydrolytic dehydrogenation system can ideally release 7.8 wt% and 12.2 wt% hydrogen of the starting materials, respectively, showing their high potential for chemical hydrogen storage. A variety of nanocatalysts have been prepared for catalytic dehydrogenation from aqueous or methanolic solution of AB and HB. In this review, we survey the research progresses in nanocatalysts for hydrogen generation from the hydrolysis or methanolysis of NH3BH3 and N2H4BH3

p-Type CaFe2O4 semiconductor nanorods controllably synthesized by molten salt method

Pure phase, regular shape and well crystallized nanorods of p-type semiconductor CaFe2O4 have been fabricated for the first time by a facile molten salt assisted method, as confirmed by XRD, TEM, SEM and HRTEM. UV-vis diffuse reflectance spectra and Mott-Schottky plots show that the band structure of the CaFe2O4 nanorods is narrower than that of the CaFe2O4 nanoparticles synthesized by conventional method. The enhancement of the visible-light absorption is due to narrowness of the band gap in CaFe2O4 nanorods. The appropriate ratio between the molten salt and the CaFe2O4 precursors plays an important role in inhibiting the growth of the crystals along the (201) plane to give the desired nanorod morphology. This work not only demonstrates that highly pure p-type CaFe2O4 semiconductor with tunable band structure and morphology could be obtained using the molten salt strategy, but also affirms that the bandgap of a semiconductor may be tunable by monitoring the growth of a particular crystal plane. Furthermore, the facile eutectic molten salt method developed in this work may be further extended to fabricate some other semiconductor nanomaterials with a diversity of morphologies. (C) 2016 Science Press and Dalian Institute of Chemical Physics. All rights reserved