Miracle-dz/UniFAR-FTUs huggingface dataset:
Études structurales d’interactions protéine/protéine impliquées dans l’érythropoïèse

Hematopoietic development is regulated through a combinatorial interplay between lineage-specific activators and the general transcription machinery that enables cell-specific patterns of gene expression. This thesis reports structural and functional studies of interactions involving the transcativation domains (TAD) of activators proteins and their role in hematopoietic development. Interactions between the TAD of activators and their partners play an important role in the transcriptional regulation of all genes including those regulating hematopoiesis. The first section reports the identification and characterization of a novel interaction between the erythroid transcription factor GATA-1 and the tumor suppressor protein p53. Using a combination of isothermal titration calorimetry (ITC), NMR spectroscopy and in vivo studies, we identified and characterized the direct interaction between these two important transcription factors in an attempt to determine the role of this interaction in erythroid development. Based on our results, the TAD of p53 directly interacts with the DNA-binding domain of GATA-1 in a cell-type specific manner. Through this interaction, GATA-1 inhibits activation of select p53regulated genes and we postulate that the inhibition of p53-dependent apoptotic pathways is essential for survival of erythroid precursor cells. In the second section, we report on the interactions between two acidic TADs and the general transcription factor IIH (TFIIH). The structure of the complexes formed by the Tfb1/p62 subunit of TFIIH (Tfb1PH/p62PH) and the acidic TAD of Herpes Simplex viral protein 16 (VP16) and the Erythroid Krüppel-like factor (EKLF) were determined by NMR spectroscopy. The structure of the Tfb1PH/VP16 complex demonstrated that a viral TAD has the ability to mimic the actions of the TAD from the human p53 with Tfb1PH/p62PH. The TADs of both VP16 and p53 adopt a 9-residue α-helix in complex with Tfb1PH/p62PH. Interestingly, the NMR structure of the EKLF/Tfb1PH complex demonstrated that despite sharing a common binding site with p53 and VP16 on Tfb1PH, the EKLF/Tfb1PH binding interface is distinctly different from the binding interfaces we previously observed with p53/Tfb1PH and VP16/Tfb1PH complexes. Surprisingly, EKLF adopted a similar binding mechanism as the
Diffraction of Sound by an Array of Rectangular Reflective Panels

An investigation in an anechoic room of the diffraction of sound by rectangular panels, similar to panels that have been used for acoustical purposes in concert halls and other auditoriums, confirms certain expectations based on well‐known properties of both optical and acoustical diffraction: namely, (1) that, for wavelengths that are large as compared to the dimensions of the panels and the spacing between them, the incident sound on the panels is essentially all transmitted, and therefore for frequencies below a certain critical value, arrays of such panels are essentially nonreflective; (2) that, for wavelengths that are small, the panels reflect most of the sound incident upon them; and (3) that, for wavelengths that are of the same order of magnitude as the dimensions of the panels and spacings, there are complex diffraction effects.
Proton-Coupled Electron Transfer of an Osmium Aquo Complex on a Self-Assembled Monolayer on Gold

A one-electron, one-proton (1e1H) redox couple based in an osmium aquo complex is attached to a self-assembled monolayer of alkanethiol on a gold electrode. The formal potential behavior of the Os aquo complex exhibits the expected pH dependence for a 1e1H system. The thermodynamic parameters are a formal potential of +0.30 V vs SCE for [Os(II/III)(H2O)], a formal potential of −0.11 V vs SCE for [Os(II/III)(OH)], a pKa of 2.4 for [Os(III)(H2O/OH)], and a pKa of 9.3 for [Os(II)(H2O/OH)]. A stepwise electron−proton transfer model, widely used in the electrochemical literature, predicts the effects of pH and overpotential on the kinetics of charge transfer for the 1e1H system. The kinetic behavior of the Os aquo complex deviates substantially from the predictions of the stepwise model. In particular, the standard rate constant and the transfer coefficient at zero overpotential are nearly independent of pH over the pH range at which proton-coupled electron transfer occurs, and Tafel plots are asymmetrical (st.
Synthesis of Copolymers Containing Double Spiro Orthocarbonate and Used as Anti-shrinkage Additives in Epoxy Resin Composite

A novel copolymer containing a double spiro orthocarbonate structure, poly 3-methylene-9-methyleneoxy-3,9-Bis(hydroxymethyl)-1,5,7,11-tetraoxaspiro[5.5] undecane (SOC), was synthesized. The structure of SOC was confirmed by 1H, 13C NMR and FTIR spectra. Prepolymer (SOCP) reacting from SOC and 2,4-toluene diisocynate (TDI) was prepared and used as anti-shrinkage additives in the cationic polymerization of epoxy resin (EP-51). The volume changes of the cured epoxy resin containing SOCP were investigated by density measurements with an electronic hydrometer. The mechanical properties of the modified epoxy resin were investigated by adhesive strength, impact strength and flexural strength, while thermal properties were investigated by thermal gravimetric analysis (TGA).
Multireference Møller–Plesset perturbation treatment of potential energy curve of N2

A multireference Moller-Plesset (MR-MP) perturbation method, at the second-order level, is applied to the potential energy curve of the ground state of N2, for comparison with a variety of standard ab initio methods. In spite of the drastic simplification, the MR-MP results are very reliable. The energy errors are almost independent of geometry, allowing unbiased treatment of potential energy curves. The potential efficiency and accuracy of the MR-MP approach are emphasized. © 1992 John Wiley & Sons, Inc.
Evidence of hot electrons generated from an AlN∕GaN high electron mobility transistor

We have observed that the temperature of the electrons drifting under a relatively high electric field in an AlN∕GaN-based high-electron-mobility transistor is significantly higher than the lattice temperature (i.e., the hot electrons are generated). These hot electrons are produced through the Frohlich interaction between the drifting electrons and long-lived longitudinal-optical phonons. By fitting electric field versus electron temperature deduced from the measurements of photoluminescence spectra to a theoretical model, we have deduced the longitudinal-optical-phonon emission time for each electron is to be on the order of 100fs.
Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump – X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new “modular” X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy  was found to be (5.0±0.3) ps, and the ratio of the Gruneisen parameters was found to be e / i = (0.5±0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A1g mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase and its development for excitations close to the ablation threshold were revealed. Such results were possible to obtain, due to the unprecedented combination of a short X-ray pulse duration and brightness at the SPPS.
Exploring schema repositories with schemr

Schemr is a search engine for users to search for and visualize schemas in a metadata repository. Users may search by keywords and by example, using schema fragments as query terms. Schemr uses a novel search algorithm, based on a combination of text search and schema matching techniques, coupled with a structurally-aware scoring metric. Schemr presents search results in a GUI that allows users to explore which elements match and how well they do. The GUI supports interactions, including panning, zooming, layout and drilling-in. This paper introduces Schemr as a new component of the information integration toolbox and discusses its benefits in several applications.
Diblock Copolymers as Scaffolds for Efficient Functionalization via Click Chemistry

A set of different alkyne containing diblock copolymers based on 4-hydroxystyrene was synthesized by nitroxide mediated radical polymerization (NMRP), all with excellent control over the molecular composition and narrow molar mass distribution. The diblock copolymers consist of labile protected 4-hydroxystyrene motifs in one block and bear alkyne functionalities in each repeating unit of the second block, thus making the materials candidates for polymer analogous modification reactions by a very efficient cycloaddition reaction. The use of 4-(trimethylsilylpropargyloxy)styrene as monomer proved highly advantageous compared to 4-(trimethylsilylethynyl) styrene, first because high control was kept in the NMRP process and second because there was higher accessibility in the postmodification reaction. In fact, quantitative postmodification through Cu(I)-catalyzed cycloaddition reaction of the pending propargyloxy groups with bulky adamantane azide of the diblock copolymers was achieved, yielding microphase-se.
Interactions of laulimalide, peloruside, and their derivatives with the isoforms of β-tubulin

The investigational anticancer agents laulimalide and peloruside are known to exert an antimitotic effect on cells by binding to β-tubulin. The binding affinities of derivatives of laulimalide and peloruside to all known isoforms of human β-tubulin were calculated using molecular mechanical, molecular dynamical, and quantum mechanical methods. Several of the derivatives are predicted to have improved β-tubulin binding affinities compared to the parent structures. These results can form the starting point for developing laulimalide or peloruside derivatives with greater specificity for the particular β-tubulin isoforms, which are overexpressed in certain tumours.
Inorganic Biochemistry: An Introduction

The ubiquity of metal ions in biology has led to widespread interest in metallobiochemistry among biologists, chemists and biochemists. This book serves primarily as a textbook for courses in bio-inorganic chemistry, and as a supplement for courses in general inorganic, co-ordination, or solution chemistry. It does not cover all the details of inorganic biochemistry, being intended as a concise and solid introduction. It is aimed at senior undergraduate and graduate students (US designation), as well as scientists in the following disciplines: biological, inorganic and organic chemistry; chemical and environmental engineering; specialized research in molecular biology and the medical sciences; biophysics. Building from a firm basis in organic co-ordination and reaction chemistry, the biological chemistry of metal ions is developed. Emphasis is placed on chemical principles rather than the techniques employed. Specific examples have been chosen to illustrate important general principles.
Small-Area Population Forecasting Using a Spatial Regression Approach

Extended abstract The use of familiar multiple regression models in the production of population forecasts for subcounty geographic entities is an empirically tested idea that has been around for more than 50 years (Schmitt, 1953 1 ; 1954 2 ). Stanbery (1952) 3 did not mention regression-based forecasts in this early “guide book” for those responsible for population forecasting for small areas and communities. But, nearly a quarter century later, Pittinger (1976) 4 , in his comprehensive review of population projection models devoted considerable attention to the matter (1976:68-77). In their recent and well-received overview on the topic, Smith, Tayman and Swanson (2000) 5
Sustainable Development in the Surf Industry: Case Study of Mormaii

The images of 'Nirvana' with beautiful beaches and perfect waves have transformed the surfing in one of the action sports most practiced worldwide and has grown significantly in the last decade. The surfer stereotype as an idle and irresponsible guy and surf as counterculture has given way to appreciation and recognition of the benefits and the economic, social and cultural potential of surfing as a sport and lifestyle. Surprisingly, there is practically no academic research on the surf industry in Brazil, despite its relevance for the economy and the environment. Therefore, this exploratory research investigates the initiatives towards sustainable development at Mormaii – the largest company in the Brazilian surf industry, discuss the key challenges for the transitions to sustainability in the surf industry in Brazil, and suggest future studies for this new field of research. This study highlights the challenge of finding a balance between the three dimensions of the triple bottom line, since the environmental and social pillars need to rely on the financial support of the economic pillar of the sustainable development.
Electronic Transition Moments of 2-Aminopurine

The electronic spectrum of the unnatural nucleic acid base 2-aminopurine is important in order to understand the spectroscopy and photophysics of the normal DNA bases. Knowledge of transition moment directions and effective absorption components is also a prerequisite for the interpretation of emission spectra of 2-aminopurine incorporated into DNA as a probe of nucleic acid base motion or excitation energy transfer processes. Using linear dichroism, fluorescence anisotropy, and ordinary and magnetic circular dichroism techniques, the near-UV spectrum of 2-aminopurine is resolved into contributions from five electronic transitions. Four moderately strong pi-->pi* transitions (I, III, IV, and V) are observed, polarized at +53 degrees (I), -72 degrees (III), -77 degrees (IV), and +57 degrees or -67 degrees (V) relative to the short molecular axis. In addition, one weak n --> pi* transition (II) polarized perpendicular to the molecular plane has been identified. Semiempirical INDO/S calculations support these assignments.
Epoxidation and Hydroxylation of Ethylenic Compounds with Organic Peracids

Oxiranes and alpha-glycols can be prepared from olefins by a variety of methods. One of the most important and generally applicable of these is the oxidation of ethylenic compounds with organic peracids. Depending on the peracid employed and/or operating conditions either an oxirane or an alpha-glycol can be obtained in good yield. It is important to note that the oxidation step both in epoxidation and hydroxylation reactions with organic peracids is the conversion of the olefin to the oxirane. Keywords: epoxidation; hydroxylation; ethylenic compound; organic peracids; stereochemistry; experimental conditions
Structure and thermopower of solid solution nickelocuprates La2−xSrxCu1−y , Niy, O4

Abstract A series of materials represented by La2-xSrx, Cu1−y. , . Niy, O4 has been prepared using a basic carbonate coprecipitation technique. The disappearance of superconductivity at higher Ni contents usually accompanies the localization of carriers at low temperatures. A metal-like temperature dependence (dR/dT > 0) occurs up to x = 0.36 and y = 0.2 with a metal-non-metal transition at low temperatures. In comparison with La1 85Sr0.15 Cu1−yNiyO4, the metal-non-metal transition can be ‘tuned’ by varying the Sr content at a given Ni content. For non-metallic samples and those materials which show localization at low temperatures, their conductivity follows the form exp[(T 0/T) v ] with ν = ¼ or ½ (variable-range hopping law), indicating that the localization of carriers is caused by disorder. When considering the effects of carrier concentrations and disorder in the system La2-xSrxCu1−yNiy.O4, the phonon-drag contribution seems to play a part in their thermopower.
Instrument Development and Measurements of the Atmospheric Pollutants Sulfur Dioxide, Nitrate Radical, and Nitrous Acid by Cavity Ring-down Spectroscopy and Cavity Enhanced Absorption Spectroscopy

Sulfur dioxide (SO2), nitrate radical (NO3), and nitrous acid (HONO) play important roles in the atmosphere. SO2 is associated with the combustion of fossil fuels and contributes to acidification of the ecosystem, particulate sulfate formation and SO2 is an EPA regulated species. NO3 is the major oxidation species at night often reacting with biogenic volatile organic hydrocarbons emitted during the nighttime air, which lead to peroxyl radical and nitric acid formation. HONO is a major source of hydroxyl radical (OH) in the early morning. All of these three pollutants exhibit strong absorptions in the UV and visible region and their absorption bands are exploited for measurements using the ultrasensitive absorption spectroscopy techniques, cavity ring-down spectroscopy (CRDS) and broadband cavity enhanced absorption spectroscopy (BBCEAS). SO2 is measured by CRDS near 308 nm in the UV region with a limit of detection of 3.5 ppb/10 seconds (S/N = 2) and ambient measurements are attempted. Instruments based on light emitting diode (LED) based BBCEAS are developed for measurements of NO3 and HONO. NO3 is monitored using the 662 nm absorption feature with a limit of detection of 10 ppt/2 minutes (1s) and the technique is demonstrated by sampling from an environmental chamber. HONO is measured in the UV region using the 368 nm absorption with a limit of detection of 10 ppb/2 minutes (1s).
Identification of flavour in fresh feijoa fruit

The aim of this study was to extract and identify volatile flavour components from peel, flesh and seeds of feijoa fruit separately and further determine its flavour profile. Obtained information is aimed to be used to develop a new flavour mixture for the food industry. The volatile flavour fraction of feijoa fruit flesh, seeds and skin were isolated by ethanol extraction and steam distillation. Further an organoleptic evaluation was carried out to distinguish flavour differences within the obtained distillates to decrease the number of samples to be analysed by gas chromatography and gas chromatography-mass spectrometry. Gas chromatography analysis resulted in 13 identified flavour compounds of the 23 reference compounds used. Results showed gas chromatography-mass spectrometry to be most successful and this technique presented a great amount of data of which seven compounds are reported for the first time as flavour compounds of feijoa fruit; citronellyl acetate, cis-rose oxide, geraniol acetate, isoamyl acetate, ethyl octanoate, D-limonene and humulane-1,6-dien-3-ol. Further analysis is needed to evaluate the extent of unique findings of flavour compounds and to evaluate how they contribute to the flavour of feijoa fruit to be able to produce a flavour mixture for the food industry.
Use of Fenton's Reagent for the Degradation of TCE in Aqueous Systems and Soil Slurries

Fenton's reaction is comprised of hydrogen peroxide (H2O2) catalyzed by iron, producing the hydroxyl radical (·OH), a strong oxidant. ·OH in turn may react with H2O2 and iron and is capable of destroying a wide range of organic contaminants. In this laboratory study, Fenton's reaction was observed in aqueous and soil slurry systems using trichloroethylene (TCE) as the target contaminant, with the goal of maximizing TCE degradation while minimizing H2O2 degradation. Fenton's reaction triggers a complex matrix of reactions involving ·OH, H2O2, iron, TCE, and soil organics. In soil slurries with a high fraction of organic carbon (fOC), iron tends to sorb to soil organics and/or particles. In aqueous systems the optimal ratio of H2O2:Fe2+:TCE to degrade TCE in a timely fashion, minimize costs, and minimize H2O2 degradation is 300 mg/L: 25 mg/L: 60 mg/L (19:1:1 molar ratio), while soil slurries with a fOC up to approximately 1% and a soil:water ratio of 1:5 (weight ratio) require about ten times the amount of H2O2, the optimal ratio being 3000 mg/L: 5 mg/L: 60 mg/L (190:0.2:1 molar ratio). TCE degradation rates were observed to decrease in soil slurries with higher fOC because of competition by soil organic matter, which appears to act as a sink for ·OH. H2O2 degradation rates tended to increase in soil slurries with higher fOC, most likely due to increased demand for ·OH by soil organics, increased available iron and other oxidation processes.