Miracle-dz/UniFAR-FTUs huggingface dataset:
Formation of crew‐cut aggregates of various morphologies from amphiphilic block copolymers in solution

Crew-cut micelle-like aggregates represent a new type of aggregate formed in solution by the self-assembly of highly asymmetric amphiphilic block copolymers. The aggregates are termed crew-cut because the dimensions of the core are bigger than those of the corona. They are prepared by first dissolving copolymers, such as polystyrene-b-poly(acrylic acid), in a common solvent, e.g. dimethylformamide (DMF), and then adding water to the solution to induce aggregation of the polystyrene segments. Since the first description of an experimental study of spherical crew-cut micelles in 1994, over 20 papers have appeared in the literature. One of the most noteworthy phenomena seen in the crew-cut aggregate systems is the existence of multiple morphologies. These include spheres, rods, vesicles, lamellae, large compound vesicles, large compound micelles and several other structures. This paper presents an overview of the phenomenon, and a description of the qualitative principles underlying the formation of crew-cut aggregates of various morphologies in solution. The main topics of this paper are the preparation of crew-cut aggregates, the critical micellization concentration, the aggregation number, the common solvent content in the core, the mobility of the core-forming blocks in the core region, and the relative importance of thermodynamics versus kinetics during micellization as a function of added water content. The formation and morphology of the crew-cuts are also compared with those in other self-assembled systems, i.e. small molecule amphiphiles in solution, block copolymers in bulk and blends of block copolymers and homopolymers. It has been found that the most important factors influencing the morphology of the aggregates are the copolymer composition, the initial copolymer concentration in solution, the added water content, the nature of the common solvent and the type and concentration of added ions (salt, acid or base). The morphology is mainly controlled by a force balance involving three factors, namely the stretching of the polystyrene (PS) blocks in the core, the surface tension between the core and the outside solvent, and the repulsion among the corona chains. The morphogenic effects of the above-mentioned parameters can, in general, be ascribed to their influence on this force balance during the formation of the aggregates. In particular, the length of corona-forming blocks or the addition of ions mainly affects the repulsive interactions of the corona chains; the effect of the water content in solution is related to the change of the surface tension between the PS core and the solvent; and the effect of changing the common solvent from DMF to tetrahydrofuran or to dioxane on the morphology is due mainly to the increased dimensions of the core-forming blocks resulting from the changes of the solvent contents in the core and the aggregation numbers. © 1998 John Wiley & Sons, Ltd.
Activated carbon from bamboo waste modified with iron and its application in the study of the adsorption of arsenite and arsenate

AbstractActivated carbon obtained from bamboo waste was synthesised and modified with iron (BAC-Fe) and used for the removal of arsenic from aqueous solutions. Two different adsorption models were used for analysing the data. The adsorption capacities were determined for BAC-arsenite, BAC-Fe-arsenite, BAC-arsenate and BAC-Fe-arsenate, with a qmax (µg g−1) of 14.89, 19.19, 22.32 and 27.32 respectively. Adsorption capacity varied as a function of pH and modifications to the sorbent. Adsorption isotherms from an aqueous solution of arsenite and arsenates on activated carbons were determined. These adsorption isotherms were consistent with the Langmuir and Freundlich adsorption models. Adsorption kinetics followed a pseudo-first order rate equation, as did the kinetics for BAC-Fe-arsenite and BAC-Fe-arsenate adsorption.
Formation of large cyclic amides by catalytic depolymerization of polyamides

Nylon 8, nylon 12, nylon 6.6, nylon 11.6 and nylon 12.12 were thermally converted into cyclic oligomers at 280 to 330°C within one to three hours. The reaction is catalyzed by small amounts of salts of different carboxylic acids and is supposed to take place by an anionic depolymerization mechanism.
Intrinsic Viscosity, Diffusion, and Sedimentation Rate of Polymers in Solution

Intrinsic viscosity, diffusion and sedimentation rate of polymers in solution is calculated by a generalization of Einstein's theory for impermeable spheres. For the coiled polymer molecule a sphere is substituted which hinders the liquid flow through its interior only to a degree depending on the average density in space of the polymer molecule in solution. The amount of shielding of the liquid flow which is introduced in this way determines the exponent in the customary exponential relation between intrinsic viscosity, diffusion, or sedimentation rate and molecular weight. This relation is shown to have only the merits of an interpolation formula. It is shown how the dimensions of the molecular coil can be derived from the experimental data on viscosity, and these dimensions are compared with those derived from interference measurements. The point is stressed that the relation between intrinsic viscosity and molecular weight is rather indirect and depends essentially on the type of polymer molecule unde.
Magnetic Properties and Electronic Structure of ThCo 4 B

We present density functional theory DFT ab initio calculation of the electronic and magnetic properties of ThCo4B compound using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method as implemented in the Wien2k package. The influence of the local environment on the Co magnetic moments is discussed by comparing the magnetic and electronic properties of ThCo4B to its parent ThCo5 compound. The total magnetic moment in these two compounds is dominated by the Co moment. The Spin orbit interaction affects the electronic structure and spin-density maps of the p-state of Th.
ROBOREBECA: A NEW FRAMEWORK TO DESIGN VERIFIED ROS-BASED ROBOTIC PROGRAMS

Robotic technology helps humans in diﬀerent areas such as manufacturing, health care and education. Due to the ubiquitous revolution, today’s focus is on mobile robots and their applications in a variety of cyber-physical systems. There are several powerful robot middlewares, such as ROS and YARP to manage the complexity of robotic software implementation. However, they do not provide support for assuring important properties such as timeliness and safety. We believe that integrating model checking with a robot middleware helps developers design and implement high quality robotic software. By deﬁning a general conceptual model for robotic programs, in this thesis we present an integration of Timed Rebeca modeling language (and its model checker) with ROS to automatically synthesize veriﬁed ROS-based robotic software. For this integration, ﬁrst the conceptual model is mapped to a Timed Rebeca model which is used to verify the desired properties on the model. The Timed Rebeca model may be modiﬁed several times until the properties are satisﬁed. Finally, the veriﬁed Timed Rebeca model is translated to a ROS program based on a set of mapping rules. Conducting experiments on some small-scale case studies indicate the usefulness and applicability of the proposed integration method.
A Label-Free Electrochemical Aptasensor for Thrombin Using a Single-Wall Carbon Nanotube ( SWCNT) Casted Glassy Carbon Electrode ( GCE)

An electrochemical aptasensor with a thrombin binding aptamer (TBA) was developed using a single-wall carbon nanotube (SWCNT) casted GCE. The TBA was immobilized on SWCNTs through π-stacking without any special modification, resulting in helical wrapping to the surface. In the presence of thrombin, the TBA binds with thrombin and the TBA concentration on the SWCNT surface decreases. The remaining amount of TBA can be analyzed by an electrochemical method without any label, because the guanine bases of the nucleic acid are measurable by electrochemical methods. The electrochemical oxidation of guanine nucleotides was enhanced by electrocatalytic mediation using Ru(bpy)32+ for higher sensitivity and reduction of the overpotential for electrochemical detection.
Non-Iterative Constraint Dynamics Using Velocity-Explicit Verlet Methods

Abstract We describe non-iterative constraint dynamics algorithms for molecular simulation based on the velocity and Beeman [1, 3] forms of the Verlet algorithm. The methods are easily adapted for constant temperature molecular dynamics, and because they are non-iterative, should prove useful for large-scale simulations on parallel computers. Test simulations of liquid butane, water, and nitrogen are used to verify the accuracy, stability, and practical utility of the methods.
Chromatographic Analysis of Pharmaceuticals

Regulatory Considerations for the Chromatographer, John A. Adamovics Sample Treatment, John A. Adamovics Planar Chromatography, John A. Adamovics and James C. Eschbach Gas Chromatography, John A. Adamovics and James C. Eschbach High-Performance Liquid Chromatography, John A. Adamovics and Daivd Farb Capillary Electrophoresis, Shelley R. Rabel and John F. Stobaugh Supercritical Fluid Chromatography of Bulk and Formulated Pharmaceuticals, James T. Stewart and Nirdosh K. Jagota Applications, John A. Adamovics
Solubility of Meloxicam in Mixed Solvent Systems

Solubility of meloxicam was determined in polyethylene glycol 400 (PEG 400), water, ethanol, propylene glycol (PG), phosphate buffer pH 7.4, Tween 80 and Brij 35 in order to understand the nature of drugvehicle interactions. Meloxicam exhibited highest solubility (7 mg/ml) in PEG 400 due to possible hydrophobic interaction of the compound with polyethylene chains. The extent of solubility of meloxicam is the same in ethanol and PG, but is higher when compared to its solubility in water, indicating the role of hydrogen bonding in the solubility of meloxicam. The solubility of meloxicam is higher in phosphate buffer (pH 7.4) compared to water, probably due to ionization of the drug. The solubility of meloxicam is marginally enhanced in surfactant systems (Tween 80 and Brij 35) at concentrations higher than cmc, proving the micellar solubilization. Meloxicam solubility studies in PEG 400 and other vehicles provide an idea to understand the nature of interactions between the drug and the solvent system employed. The solubility of meloxicam is highest (12 mg/ml) in PEG 400-phosphate buffer in the ratio of 40:60. This vehicle may have the matching polarity with that of meloxicam. These results were in agreement with the values for cosolvents obtained from Setschenow equation. The functional groups in meloxicam have definite role in the solubilization and that hydrophobic interaction is predominant with PEG 400 vehicles. Keywords : meloxicam, cosolvency, solubility enhancement, parenteral preparations, ophthalmic drops Ethiopian Pharmaceutical Journal Vol. 25 (1) 2007: pp. 23-28
Chip-Scale Bioassays Based on Surface-Enhanced Raman Scattering: Fundamentals and Applications

This work explores the development and application of chip-scale bioassays based on surface-enhanced Raman scattering (SERS) for high throughput and high sensitivity analysis of biomolecules. The size effect of gold nanoparticles on the intensity of SERS is first presented. A sandwich immunoassay was performed using Raman-labeled immunogold nanoparticles with various sizes. The SERS responses were correlated to particle densities, which were obtained by atomic force microscopy (AFM). The response of individual particles was also investigated using Raman-microscope and an array of gold islands on a silicon substrate. The location and the size of individual particles were mapped using AFM. The next study describes a low-level detection of Escherichia coli 0157:H7 and simulants of biological warfare agents in a sandwich immunoassay format using SERS labels, which have been termed Extrinsic Raman labels (ERLs). A new ERL scheme based on a mixed monolayer is also introduced. The mixed monolayer ERLs were created by covering the gold nanoparticles with a mixture of two thiolates, one thiolate for covalently binding antibody to the particle and the other thiolate for producing a strong Raman signal. An assay platform based on mixed self-assembled monolayers (SAMs) on gold is then presented. The mixed SAMs were prepared frommore » dithiobis(succinimidyl undecanoate) (DSU) to covalently bind antibodies on gold substrate and oligo(ethylene glycol)-terminated thiol to prevent nonspecific adsorption of antibodies. After the mixed SAMs surfaces, formed from various mole fraction of DSU were incubated with antibodies, AFM was used to image individual antibodies on the surface. The final study presents a collaborative work on the single molecule adsorption of YOYO-I labeled {lambda}-DNA at compositionally patterned SAMs using total internal reflection fluorescence microscopy. The role of solution pH, {lambda}-DNA concentration, and domain size was investigated. This work also revealed the potential importance of structural defects. « less
Small-Angle Neutron Scattering Investigation of the Temperature-Dependent Aggregation Behavior of the Block Copolymer Pluronic L64 in Aqueous Solution†

Small-angle neutron scattering (SANS) was used to investigate the temperature dependence of the structure of micelles formed by the poly(ethylene oxide)−poly(propylene oxide)−poly(ethylene oxide) Pluronic L64 amphiphilic block copolymer in aqueous (D2O) solution. Different models for the form factor and the structure factor have been considered for fitting the SANS scattering patterns. By comparing the various models, we found that in the intermediate block copolymer concentration range, e.g., 2.5 wt % Pluronic L64, the micelles are well separated while the intermicellar interaction remains strong. Thus the more appropriate model was that of core−corona form factor and hard sphere structure factor, which allowed the determination of the core, micelle, and hard sphere interaction radii, the micelle association number, and the solvent volume fraction in the micelle core and corona. Upon an increase of temperature (in the range 35−55 °C) the micelle radius increased by ≈10%, accompanied by the loss of water .
Mechanistic investigation of coordinated conformational changes in multisubunit ion channels and enzymes

Many enzymes and ion channels consist of multiple subunits and/or multiple distinct functional components. Coordinated conformational changes through allosteric interactions between subunits and/or between functional units can efficiently regulate protein activity. This dissertation describes investigations of coordinated conformational changes in two systems: the ATP-sensitive potassium (KATP) channel and the ATPdependent bacterial protease, ClpAP. KATP channels consist of two protein subunits: a pore-forming subunit, Kir6.2 and a regulatory subunit, SUR1. Kir6.2 is an inwardly rectifying potassium channel, and SUR1 belongs to the ATP-binding cassette (ABC) superfamily. Using patch clamp techniques, KATP channel activity was observed directly with single-channel resolution. The results indicate that noise from stochastic channel gating is significantly reduced compared to what would be observed for identical and independent channels, and provide evidence that negatively cooperative interactions between neighboring KATP channels are the source of the noise reduction. Simulations further suggest that negative coupling among KATP channels in pancreatic beta cells could be important for reliable signal transduction. Energetic coupling between Kir6.2 and SUR1 subunits was also investigated. Single-channel records were analyzed to detect the violations of microscopic reversibility in channel gating that would occur if Kir6.2 conformational transitions were driven by the energy from ATP hydrolysis by SUR1. Although no violations of detailed balance in channel gating are detected on the time scale where ATP hydrolysis takes place, unexpected non-equilibrium gating is observed on longer time scales. These results imply that channel gating is coupled to non-equilibrium processes other than ATP hydrolysis by SUR1. The second system studied for coordinated conformational change was ClpAP. ClpAP is composed of an ATPase, ClpA and a serine peptidase, ClpP. ClpA uses the free energy of ATP hydrolysis to unfold protein substrates and translocate them to ClpP, which proteolyzes them. To investigate how protein translocation by ClpA is coupled to proteolysis by ClpP, size distributions of peptide products were measured. The observation of non-exponential size distributions, in combination with simulations predicting how different mechanisms would influence the size distribution, supports the hypothesis that peptide product sizes are controlled by coordinated conformational changes of ClpA and ClpP. Thesis Supervisor: Stuart S. Licht Title: Samuel A. Goldblith Career Development Assistant Professor of Chemistry
AB-INITIO CALCULATION OF EXCITED STATE ABSORPTION OF CR4+ IN Y3AL5O12

The Cr3+ and Cr4+ impurity states in Y3Al5O12 (YAG) crystal are studied by ab-initio supercell calculations using the density-functional theory. Calculations are carried out with Cr substitutions at the octahedral and tetrahedral Al sites including the effect of Ca co-doping. Optical transitions between various levels and to conduction band states are also calculated. A model for excited state absorption for Cr4+ in YAG is proposed.
Pierre François Verhulst

Pierre-Francois Verhulst est un mathematicien belge, ne le 28 octobre 1804, et mort le 15 fevrier 1849 a Bruxelles. Il etudie les mathematiques sous la direction de Quetelet. Inspire par l'Essai sur le principe de population de Thomas Malthus, il propose en 1838 un modele decrivant l'evolution des populations animales de facon non exponentielle. La courbe obtenue est nomme courbe « logistique » dans une publication de 1845. Voici des courbes obtenues en fonction du « taux de fecondite » (avec, au (.)
(Mg,Co)O Solid-Solution Precursors for the Large-Scale Synthesis of Carbon Nanotubes by Catalytic Chemical Vapor Deposition

Single- and double-walled carbon nanotubes were produced in high yield using the selective reduction of solid solutions of Mg1–xCoxO in a methane and hydrogen atmosphere at 1000°C. The solid solutions were prepared using combustion synthesis with urea as the fuel. The BET surface areas ranged from 10 to 65 m2/g depending on the fuel content. A single crystalline phase was obtained only for fuel-rich compositions. Increased fuel content increased the surface area by a factor of 6. However, very high fuel contents (>4 times the stoichiometric amount) caused a demixed solid solution. Surface-area measurements and Raman spectra showed that the quantity of nanotubes formed depended on the surface area and composition of the precursor oxide.
Przykłady cyfrowego przetwarzania sygnałów w LabVIEW.

Pierwszy rozdzial obejmuje podstawy programowania w LabVIEW i zestawienie algorytmow przetwarzania sygnalow dostepnych w tym środowisku. W rozdziale drugim omowiono takie zagadnienia jak probkowanie, kwantyzacja, aliasing, analiza widmowa, okno czasowe prostokątne i wygladzające. W rozdziale trzecim i czwartym przedstawiono filtry cyfrowe o skonczonej i nieskonczonej odpowiedzi impulsowej oraz filtracje adaptacyjną. Ostatni rozdzial dotyczy analizy czasowo-czestotliwościowej: krotkookresowej transformaty Fouriera STFT i analizy falkowej. Kazde omawiane zagadnienie zilustrowano przykladami programow przygotowanych w graficznym środowisku programowania LabVIEW.
CONSUMO, DIGESTIBILIDADE E PARÂMETROS FISIOLÓGICOS DE OVELHAS SUPLEMENTADAS COM NÍVEIS CRESCENTES DE PROPILENOGLICOL NA ÁGUA

Objetivou-se com o presente trabalho avaliar o consumo, digestibilidade e parâmetros fisiologicos de ovelhas suplementadas com niveis crescentes de propilenoglicol. O ensaio experimental foi conduzido no Setor de Caprinos e Ovinos da Universidade Federal de Uberlândia e teve duracao de 75 dias. Foram utilizadas 5 ovelhas da raca Santa Ines, alojadas em gaiolas metabolicas, com piso ripado, bebedouro e comedouro. Foi utilizada como racao a silagem de milho e nucleo mineral especifico para a especie. As racoes foram divididas em duas refeicoes e oferecidas aos animais as 08 horas e as 16 horas. A agua foi ofertada ad libitum e misturada ao propilenoglicol. Os niveis de inclusao de propilenoglicol foram 0; 1,5; 3,0; 4,5 e 6,0%. As variaveis estudadas foram: consumo de alimento, comportamento alimentar, consumo de agua, consumo de propilenoglicol, escore fecal, digestibilidade, parâmetros fisiologicos, pH ruminal e temperatura do liquido ruminal. A inclusao de propilenoglicol em niveis crescentes na agua reduz o consumo de agua e nao altera o consumo e a digestibilidade da materia seca. Ademais, a inclusao de propilenoglicol nao altera os parâmetros fisiologicos de ovelhas, como movimentos ruminais, temperatura retal e frequencia respiratoria, o que evidencia que esse composto pode ser adicionado na dieta de ovelhas ate o nivel de 6%.
Electron distributions in peptides and related molecules. Experimental and theoretical study of Leu-enkephalin trihydrate

The crystal structure, thermal vibrations, and electron density of leu-enkephalin trihydrate, C 28 H 37 N 5 O 7 . 3H 2 O, have been analyzed using single-crystal-X-ray diffraction data measured at 100 K with Mo Kα radiation to a resolution corresponding to [(sin θ)/λ]max=1.15 A -1 . A multipolar atom density model was fitted against the 5444 unique data with I>2σ(I) [R(F)=0.038, R w (F)=0.023, GOF=0.73] in order to calculate the phases for the crystal structure factors and map the valence electron distribution. Ab initio SCF calculations have been carried out on molecular fragments with extended basis sets including polarization functions
Optimal synchronization control of multiple euler-lagrange systems via event-triggered reinforcement learning

In this paper, an event-triggered reinforcement learning-based met-hod is developed for model-based optimal synchronization control of multiple Euler-Lagrange systems (MELSs) under a directed graph. The strategy of event-triggered optimal control is deduced through the establishment of Hamilton-Jacobi-Bellman (HJB) equation and the triggering condition is then proposed. Event-triggered policy iteration (PI) algorithm is then borrowed from reinforcement learning algorithms to find the optimal solution. One neural network is used to represent the value function to find the analytical solution of the event-triggered HJB equation, weights of which are updated aperiodically. It is proved that both the synchronization error and the weight estimation error are uniformly ultimately bounded (UUB). The Zeno behavior is also excluded in this research. Finally, an example of multiple 2-DOF prototype manipulators is shown to validate the effectiveness of our method.