Aqua­bis­(3-fluoro­benzoato-κO)(1,10-phenanthroline-κ2 N,N′)copper(II)

In the title compound, [Cu(C7H4FO2)2(C12H8N2)(H2O)], the coordination around the CuII atom is square-pyramidal. The equatorial positions are occupied by two N atoms from a 1,10-phenanthroline ligand [Cu—N = 2.008 (3) and 2.019 (3) Å] and two O atoms from 3-fluoro­benzoate ligands and a water mol­ecule [Cu—O = 1.950 (2) and 1.978 (2) Å]. One O atom from another 3-fluoro­benzoate ligand occupies the apical positon [Cu—O = 2.210 (2) Å]. Hydrogen bonds occur between coordinated water mol­ecules and benzoate ligands, while O—H⋯O, C—H⋯O, C—H⋯F and π–π stacking [centroid–centroid distance = 3.731 (2) Å] inter­actions consolidate the crystal packing

DNA Methylation in Development

Early embryonic development is a very precise and complicated process. When a sperm meets an egg, a series of well-orchestrated changes take place, which end up with distinct types of cells that make up an organism. Cells start from a pluripotent state and differentiate without changes in DNA sequence. A differentiated cell shares the same DNA sequence with the zygote from which it is descended (mammalian B and T cells being an exception). The diverse functions of different cells are due to tissue-specific patterns of gene expression, which are established during development; once the fates of the cells are decided, they will be maintained faithfully through cell divisions. Hence it is reasonable to assert that development is, by definition, an epigenetic process (Reik, 2007). The specific gene expression programs in differentiated cells are regulated by a more flexible system, which dynamically switches on and off the genes for maintaining homeostasis or responding to environmental changes. Epigenetics is defined as “the study of heritable changes in genome function that occur without alterations to the DNA sequence” (Probst, et al., 2009). Epigenetics has been suggested as the key regulatory system in early development. Mechanistically, epigenetic regulation involves the covalent modification of chromatin components such as DNA methylation and histone modifications (acetylation, methylation and phosphorylation are the best characterized). Short and long non-coding RNAs are also part of the epigenetic regulatory system because of their role in targeting the chromatin modifications within the genome (Hawkins & Morris, 2008; Morris, 2009a). DNA methylation at the cytosine residue of CpG dinucleotides is the most studied epigenetic modification in mammals. Its effects on genome function underlie a number of physiological phenomena such as genomic imprinting and X chromosome inactivation, and it also contributes to the genesis of human cancers and to aging. CpG methylation was the only known chemical modification of mammalian genomic DNA with an epigenetic role before the discovery of 5-hydroxymethylcytosine that will be discussed later (Haluskova, 2010; Ohgane, et al., 2008). CpG methylation is stable, heritable and reversible, which fulfils the requirement for a dynamic regulation system for development. DNA methylation is most vulnerable to the environment during early development, because the genome methylation pattern is established during this stage and the DNA synthetic rate is very high in the early embryo. In mammals, proper DNA methylation is essential for normal development. Aberrant methylation patterns are involved in various developmental pathological phenomena and even diseases in adult life that are known under the rubric: the Developmental Origin of Health and Disease (DOHaD) (Waterland & Michels, 2007). In this chapter, we will discuss the biochemistry of DNA CpG methylation including the enzymes catalyzing the process and the controversial pathways of DNA demethylation. The dynamics of DNA methylation in early development will be covered as well as the role of methylation in cell-lineage determination, imprinting and the genesis of germ cells. We will also review the evidence supporting the importance of DNA methylation in DOHaD

Mitigating Greenhouse Gas and Ammonia Emissions from Swine Manure Management : A System Analysis

PMID: 28318241. We thank all our colleagues for their recommendations and support during this extensive study. Funding for the study was provided by the National Basic Research Program of China (2012CB417104), the Non-Profit Research Foundation for Agriculture (201303091), China Agriculture Research System (CARS-36), and UK-China Virtual Joint Centres on Nitrogen “N-Circle” and “CINAg” funded by the Newton Fund via UK BBSRC/NERC (BB/N013484/1 and BB/N013468/1, respectively).Peer reviewedPostprintPostprintPostprin

Understanding the high activity of mildly reduced graphene oxide electrocatalysts in oxygen reduction to hydrogen peroxide

The direct electrochemical synthesis of hydrogen peroxide (H2O2) would provide an attractive alternative to the traditional anthraquinone oxidation process for continuous on-site applications. Its industrial viability depends greatly on developing cost-effective catalysts with high activity and selectivity. Recent experiments have demonstrated that mildly reduced graphene oxide (mrGO) electrocatalysts exhibit highly selective and stable H2O2 formation activity [e.g., H. W. Kim, M. B. Ross, N. Kornienko, L. Zhang, J. Guo, P. Yang and B. D. McCloskey, Nat. Catal., 2018, 1, 282-290]. However, the identification of active site structures for this catalytic process on mrGO is doubtful. Herein, by means of first-principles calculations, we examine the H2O2 formation activities of the active site structures proposed in experiments and find that their activities are actually very low. Then, we systematically investigate the H2O2 formation activities of different oxygen functional group structures on mrGO based on experimental observations, and discover two types of oxygen functional group structures (2EP and 1ET + 1EP) that have comparable or even lower overpotentials (<0.10 V) for H2O2 formation compared with the state-of-the-art PtHg4 electrocatalyst. Our theoretical results reveal that the graphene edge and the synergetic effects between different oxygen functional groups are essential for the superior performance of mrGO for H2O2 production. This work not only provides a feasible explanation of the cause of high H2O2 formation activity of mrGO but also offers a guide for the design, synthesis, and mechanistic investigation of advanced carbon-based electrocatalysts for effective H2O2 production.This research was undertaken with the assistance of resources provided by the National Computational Infrastructure (NCI) facility at the Australian National University; allocated through both the National Computational Merit Allocation Scheme supported by the Australian Government and the Australian Research Council grant LE160100051 (Maintaining and enhancing merit-based access to the NCI National Facility, 2016–2018). The study was financed by an ARC Discovery Grant (DP170104853)

Individual stable space : an approach to face recognition under uncontrolled conditions

There usually exist many kinds of variations in face images taken under uncontrolled conditions, such as changes of pose, illumination, expression, etc. Most previous works on face recognition (FR) focus on particular variations and usually assume the absence of others. Instead of such a ldquodivide and conquerrdquo strategy, this paper attempts to directly address face recognition under uncontrolled conditions. The key is the individual stable space (ISS), which only expresses personal characteristics. A neural network named ISNN is proposed to map a raw face image into the ISS. After that, three ISS-based algorithms are designed for FR under uncontrolled conditions. There are no restrictions for the images fed into these algorithms. Moreover, unlike many other FR techniques, they do not require any extra training information, such as the view angle. These advantages make them practical to implement under uncontrolled conditions. The proposed algorithms are tested on three large face databases with vast variations and achieve superior performance compared with other 12 existing FR techniques.<br /

Electrocatalytic Reduction of Carbon Dioxide to Methane on Single Transition Metal Atoms Supported on a Defective Boron Nitride Monolayer: First Principle Study

The electrochemical conversion of carbon dioxide (CO2) and water into useful multi‐electron transfer products, such as methanol (CH3OH) and methane (CH4), is a major challenge in facilitating a closed carbon cycle. Here, a systematic first principle study of the potential of single transition metal atoms (Sc to Zn, Mo, Rh, Ru, Pd, Ag, Pt, and Au) supported on experimentally available defective boron nitride monolayers with a boron monovacancy (TM/defective BN) to achieve highly efficient electrocatalytic CO2 reduction (ECR) to CH4 is carried out. Our computations reveal that Fe/defective BN, Co/defective BN, and Pt/defective BN nanosheets possess outstanding ECR activities with quite low (less negative) onset potentials of −0.52, −0.68, and −0.60 V, respectively. Given that Fe and Co are nonprecious metals, Fe/defective BN and Co/defective BN may provide cost‐effective electrocatalysts. The high ECR activities of these TM/defective BN catalyst systems stem from the moderate electrocatalysts’ affinities for C and O, which modulate the free energies of ECR intermediates in the reaction pathways. Moreover, it is found that Fe/defective BN and Pt/defective BN show high selectivity of ECR to CH4. This finding highlights a strategy to design highly active and selective single‐atom electrocatalysts for ECR to CH4.S.S. and H.A. acknowledge the financial support by the Australian Research Council under Discovery Project (DP170104853). This research was undertaken with the assistance of resources provided by the National Computing Infrastructure facility at the Australian National University, allocated through both the National Computational Merit Allocation Scheme supported by the Australian Government and the Australian Research Council grant LE120100181 (Enhanced merit-based access and support at the new NCI petascale supercomputing facility, 2012–2015)