Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Signaling Recognition Events with Fluorescent Sensors and Switches.

BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

“Bioinformatics” 특집을 내면서

1. Advantages of Chemical Redox Agents 878 2. Disadvantages of Chemical Redox Agents 879 C. Potentials in Nonaqueous Solvents 879 D. Reversible vs Irreversible ET Reagents 879 E. Categorization of Reagent Strength 881 II. Oxidants 881 A. Inorganic 881 1. Metal and Metal Complex Oxidants 881 2. Main Group Oxidants 887 B. Organic 891 1. Radical Cations 891 2. Carbocations 893 3. Cyanocarbons and Related Electron-Rich Compounds 894

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Chemical Redox Agents for Organometallic Chemistry

Denitrification is a distinct means of energy conservation, making use of N oxides as terminal electron acceptors for cellular bioenergetics under anaerobic, microaerophilic, and occasionally aerobic conditions. The process is an essential branch of the global N cycle, reversing dinitrogen fixation, and is associated with chemolithotrophic, phototrophic, diazotrophic, or organotrophic metabolism but generally not with obligately anaerobic life. Discovered more than a century ago and believed to be exclusively a bacterial trait, denitrification has now been found in halophilic and hyperthermophilic archaea and in the mitochondria of fungi, raising evolutionarily intriguing vistas. Important advances in the biochemical characterization of denitrification and the underlying genetics have been achieved with Pseudomonas stutzeri, Pseudomonas aeruginosa, Paracoccus denitrificans, Ralstonia eutropha, and Rhodobacter sphaeroides. Pseudomonads represent one of the largest assemblies of the denitrifying bacteria within a single genus, favoring their use as model organisms. Around 50 genes are required within a single bacterium to encode the core structures of the denitrification apparatus. Much of the denitrification process of gram-negative bacteria has been found confined to the periplasm, whereas the topology and enzymology of the gram-positive bacteria are less well established. The activation and enzymatic transformation of N oxides is based on the redox chemistry of Fe, Cu, and Mo. Biochemical breakthroughs have included the X-ray structures of the two types of respiratory nitrite reductases and the isolation of the novel enzymes nitric oxide reductase and nitrous oxide reductase, as well as their structural characterization by indirect spectroscopic means. This revealed unexpected relationships among denitrification enzymes and respiratory oxygen reductases. Denitrification is intimately related to fundamental cellular processes that include primary and secondary transport, protein translocation, cytochrome c biogenesis, anaerobic gene regulation, metalloprotein assembly, and the biosynthesis of the cofactors molybdopterin and heme D1. An important class of regulators for the anaerobic expression of the denitrification apparatus are transcription factors of the greater FNR family. Nitrate and nitric oxide, in addition to being respiratory substrates, have been identified as signaling molecules for the induction of distinct N oxide-metabolizing enzymes.

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Cell biology and molecular basis of denitrification.

Non-innocent ligands in bioinorganic chemistry—An overview

Copper is a bioessential element in biology with truly unique chemical characteristics in its two relevant oxidation states +I and +II. Significant progress has been made in recent years in the elucidation of the frequently surprising biochemistry of this trace element. Those advances were especially furthered through mutual stimulation involving results from biochemistry, molecular biology, and medicine on one hand and the synthesis as well as the structural and spectroscopic characterization of low molecular weight model complexes on the other. The most notable features of protein-bound active copper are its almost exclusive function in the metabolism of O2 or N/O compounds (NO, N2O) and its frequent association with oxidizing organic and inorganic radicals such as tyrosyl, semiquinones, superoxide, or nitrosyl. This unique biological role of copper can be rationalized given its chemical and assumed evolutionary background.

Copper—A “Modern” Bioelement

The potential of redox-active ligands to behave “noninnocently” in transition-metal coordination compounds is reflected with respect to various aspects and situations. These include the question of establishing “correct” oxidation states, the identification and characterization of differently charged radical ligands, the listing of structural and other consequences of ligand redox reactions, and the distinction between barrierless delocalized “resonance” cases Mn/Ln ↔ Mn+1Ln–1 versus separated valence tautomer equilibrium situations Mn/Ln ⇌ Mn+1Ln–1. Further ambivalence arises for dinuclear systems with radical bridge Mn(μ-L•)Mn versus mixed-valent alternatives Mn+1(μ-L–)Mn, for noninnocent ligand-bridged coordination compounds of higher nuclearity such as (μ3-L)M3, (μ4-L)M4, (μ-L)4M4, or coordination polymers. Conversely, the presence of more than one noninnocently behaving ligand at a single transition-metal site in situations such as Ln–M–Ln–1 or L•–M–L• may give rise to corresponding ligand-to-ligand ...

Manifestations of noninnocent ligand behavior.

Three angular ditopic ligands (1,3-bis(benzimidazol-1-ylmethyl)-4,6-dimethylbenzene L1, 1,3-bis(benzimidazol-1-ylmethyl)-2,4,6-trimethylbenzene L2, and 1,4-bis(benzimidazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene L3) and one tripodal ligand 1,3,5-tris(benzimidazol-1-ylmethyl)-2,4,6-trimethylbenzene L4 have been prepared. Reaction of these shape-specific designed ligands with different metal salts affords a series of discrete molecular architectures:  [Ag2L12](BF4)2 1, [Ag2L22](CF3SO3)2 2, [CF3SO3- ⊂ Ag2L32]CF3SO3 3, [CF3SO3- ⊂ Ag2L33]CF3SO3 4, [ClO4- ⊂ Cu2L24](ClO4)3 5, [4H2O ⊂ Ni2L24Cl4]·6H2O 6, [BF4- ⊂ Ag3L42](BF4)2 7, [ClO4- ⊂ Ag3L42](ClO4)2 8, and [CuI32- ⊂ Cu3L42]2[Cu2I4] 9. The compounds were characterized by elemental analysis, ESI-MS, IR, and NMR spectroscopy, and X-ray crystallography. 1 is a dinuclear metallacycle with 2-fold rotational symmetry in which two syn-conformational L1ligands are connected by two linearly coordinated Ag+ ions. 2 and 3 are structurally related, consisting of rectangular...

Ligand-Directed Molecular Architectures: Self-Assembly of Two-Dimensional Rectangular Metallacycles and Three-Dimensional Trigonal or Tetragonal Prisms

Wolfgang Kaim

Papers

Non-innocent ligands in bioinorganic chemistry—An overview

Copper—A “Modern” Bioelement

Manifestations of noninnocent ligand behavior.

Ligand-Directed Molecular Architectures: Self-Assembly of Two-Dimensional Rectangular Metallacycles and Three-Dimensional Trigonal or Tetragonal Prisms

The transition metal coordination chemistry of anion radicals