gebhart/patrepeval huggingface dataset:
Metallo-Organic Chemical Vapor Deposition (MOCVD) for the Development of Heterogeneous Catalysts (1998)

A heterogeneous copper catalyst was developed using a novel techniquemetallo-organic chemical vapor deposition (MOCVD). Highly porous activated carbon was selected as the catalyst support to provide a high specific area. Copper acetylacetonate was used as the precursor. The precursor was evaporated by heating, transported using carrier gas, deposited into the mesopores and micropores of the support, and finally decomposed and reduced under controlled conditions to elemental metal. A vacuum is applied to enhance the volatility of the precursor. The effects of the carrier gas flow rate and deposition time were studied. The developed catalyst was characterized using the appropriate analytical methods, and its catalytic efficiency was evaluated in the catalytic wet oxidation of phenol solution. The heterogeneous catalyst developed by MOCVD was found to be a monolayer and has a higher catalytic efficiency than that prepared by the impregnation method.
Parallel-Plate Sensors for Nondestructive Measurement of Moisture Content in In-Shell Peanuts (2006)

In earlier work reported, parallel-plate capacitance sensors were used to determine theaverage moisture content (MC) of small samples of in-shell peanuts (peanut pods). In this method,seven or eight peanut pods were held between two parallel metal electrodes and the capacitance,phase angle and/or dissipation factor of the system were measured at frequencies of 1, 5 and 9MHz. The measured values were used in an empirical equation and the average MC values werecalculated. In the present work two parallel-plate electrodes were mounted inside a cylinder, madeof acrylic material, and the space between the plates was filled with peanut pods. The impedancemeasurements were made on the cylinder system and the average MC of the peanut pods was determined from a similar empirical equation. The calculated MC values were compared with theiroven-determined values and were found to be within 1% of the standard oven values for 90% of thesamples tested in the moisture range between 6 and 20%. Two parallel-plate sensors with differentplate separations, and peanuts from 2004 and 2005 harvests, were used in these measurements.The method being rapid and nondestructive, is suitable for the development of a practical instrumentfor measurement of moisture content in in-shell peanuts.
An extended authorization model for relational databases (1997)

We propose two extensions to the authorization model for relational databases defined originally by P.G. Griffiths and B. Wade (1976). The first extension concerns a new type of revoke operation, called noncascading revoke operation. The original model contains a single, cascading revoke operation, meaning that when a privilege is revoked from a user, a recursive revocation takes place that deletes all authorizations granted by this user that do not have other supporting authorizations. The new type of revocation avoids the recursive revocation of authorizations. The second extension concerns negative authorization which permits specification of explicit denial for a user to access an object under a particular mode. We also address the management of views and groups with respect to the proposed extensions.
Roles of CD133 in microvesicle formation and oncoprotein trafficking in colon cancer (2018)

Extracellular vesicles contain various cellular components that are involved in tumor growth, metastasis, and immune escape. Extracellular vesicles are classified into 2 groups, namely, exosomes and microvesicles (MV). Although the formation and roles of exosomes have been studied, the exact functions of MVs and mechanisms underlying MV release are not fully understood. We found that epidermal growth factor accelerates the release of MVs from the plasma membrane by inducing NF-κB activation and CD133 expression. The amount and sizes of budding MVs were found to be dependent on the expression level of CD133, which regulates the activities of the small guanosine 5'-triphosphatases RhoA and Rac1. CD133-containing MVs released from KRAS mutant colon cancer cells delivered KRAS mutant to adjacent nontumorigenic cells and activated KRAS downstream signaling. CD133-containing MVs were found to promote the migration and invasion of adjacent cells. CD133-containing MVs induced the development of chemoresistance by abolishing the inhibitory effects of anti-epidermal growth factor receptor (EGFR) drugs on cell proliferation and motility in colon cancer. These results suggest that CD133 acts as a novel modulator in MV release and in oncoprotein trafficking. CD133 can serve as a therapeutic target for treatment of anti-EGFR drug-resistant colon cancer.-Kang, M., Kim, S., Ko, J. Roles of CD133 in microvesicle formation and oncoprotein trafficking in colon cancer.
Perceptual display : exceeding display limitations by exploiting the human visual system (2012)

Existing displays have a number of limitations, which make it difficult to realistically reproduce real-world appearance; discrete pixels are used to represent images, which are refreshed only a limited number of times per second, the output luminance range is much smaller than in the real world, and only two dimensions are available to reproduce a three-dimensional scene.\n\nWhile in some cases technology advanced and higher frame rates, higher resolution, higher luminance, and even disparity-based stereo is possible, these solutions are often costly and, further, it is challenging to produce adequate content.\n\nOn the other hand, the human visual system has certain limitations itself, such as the density of photoreceptors, imperfections in the eye optics, or the limited ability to discern high-frequency information. The methods presented in this dissertation show that taking these properties into account can improve the efficiency and perceived quality of displayed imagery. More precisely, those techniques make use of perceptual effects, which are not measurable physically, that will allow us to overcome the physical limitations of display devices in order to enhance apparent image qualities.
Textual fragments, openness of enquiry and information systems: An example from an ERP implementation (2010)

In this paper, we will use this textual fragment from an interview to demonstrate a set of approaches that allow us to critique the initial reading of events. In doing so, we come to a deeper view of the development process. We will see interpretations of the project from a variety of perspectives and in the process shed light on the conundrum of success and failure in Information Systems projects. Our primary goal is to increase our understanding of the Information Systems Development (ISD) change process and at the same time maintain openness of inquiry. Additionally, we use the textual analysis to illustrate the use of the hermeneutical circle. Finally, many research projects in information systems (IS) employ interviews of subjects and develop large corpuses of data transcripts. We believe that our approach adds an additional weapon to the armory of the IS researcher in making sense of such textual âdatabasesâ and producing more interesting and insightful readings.
A Monoclonal Antibody to <i>Bacillus anthracis</i> Protective Antigen Defines a Neutralizing Epitope in Domain 1 (2006)

Antibody (Ab) responses to Bacillus anthracis toxins are protective, but relatively few protective monoclonal antibodies (MAbs) have been reported. Protective antigen (PA) is essential for the action of B. anthracis lethal toxin (LeTx) and edema toxin. In this study, we generated two MAbs to PA, MAbs 7.5G and 10F4. These MAbs did not compete for binding to PA, consistent with specificities for different epitopes. The MAbs were tested for their ability to protect a monolayer of cultured macrophages against toxin-mediated cytotoxicity. MAb 7.5G, the most-neutralizing MAb, bound to domain 1 of PA and reduced LeTx toxicity in BALB/c mice. Remarkably, MAb 7.5G provided protection without blocking the binding of PA or lethal factor or the formation of the PA heptamer complex. However, MAb 7.5G slowed the proteolytic digestion of PA by furin in vitro, suggesting a potential mechanism for Ab-mediated protection. These observations indicate that some Abs to domain 1 can contribute to host protection.
Adaptive linear interference suppression for packet DS‐CDMA (1998)

Abstract The performance of adaptive linear interference suppression is studied in the context of packet DS‐CDMA. A multi‐cell system is assumed with stochastic arrivals and departures of asynchronous users, and additive Gaussian noise as the only channel impairment. Interference suppression is achieved with a tapped‐delay line filter, where the filter spans a single symbol interval. Adaptive algorithms considered include the stochastic gradient (LMS), exponentially‐weighted Least Squares (LS), block LS, and a reduced‐rank LS algorithm. The reduced‐rank LS algorithm first projects the received signal onto a signal sub‐space spanned by eigenvectors of the averaged outer product matrix of received vectors. The purpose of the projection is to eliminate low‐level background interference and noise. Both decision‐directed and blind algorithms, which do not require a training sequence, are compared. Computer simulation is used to obtain error rates as a function of traffic load, and algorithm and system parameters (including timing offset). Results indicate that the adaptive algorithms offer a significant increase in capacity (nearly a factor of two at moderate error rates), and are insensitive to variations in received power over the user population.
Thick Film Resistors with Improved Voltage Stability (1974)

Thick film resistors have been prepared by adding glass frits to the conductive materials of the resistors. By this method, it is found that the resistance of the glass phases in the thick film resistors decreases, with a resulting decrease of voltage drift after applying high voltage pulses to the resistors. In addition, the electrical properties and stability of these resistors are improved over resistors made from some present commercially available pastes.
One-pot synthesis of nanotube-based hierarchical copper silicate hollow spheres (2008)

A new type of hierarchical structure, copper silicate hollow spheres assembled by nanotubes, was synthesized via a simple one-pot route by using silica colloidal spheres as chemical template.
Synthetic studies on scytophycin C / total synthesis of swinholide A (1994)

This thesis was digitised by the British Library from microfilm. You can acquire a single copy of this thesis for research purposes by clicking on the padlock icon on the thesis file. Please be aware that the text in the supplied thesis pdf file may not be as clear as text in a thesis that was born digital or digitised directly from paper due to the conversion in format. However, all of the theses in Apollo that were digitised from microfilm are readable and have been processed by optical character recognition (OCR) technology which means the reader can search and find text within the document. If you are the author of this thesis and would like to make your work openly available, please contact us: thesis@repository.cam.ac.uk
A Review of Trimming in Isogeometric Analysis: Challenges, Data Exchange and Simulation Aspects (2017)

We review the treatment of trimmed geometries in the context of design, data exchange, and computational simulation. Such models are omnipresent in current engineering modeling and play a key role for the integration of design and analysis. The problems induced by trimming are often underestimated due to the conceptional simplicity of the procedure. In this work, several challenges and pitfalls are described.
A novel topology of zero-current-switching voltage-source PWM inverter for high-power applications (1998)

A new scheme of a soft-switched voltage-source inverter (VSI) capable of true pulse-width modulation (PWM) is presented. It utilizes inductors in series with the main switches to limit di/dt during turn on, while the inductor energy is recovered by a resonant turn-off process, which is allowed by the presence of two auxiliary switches. As inductive di/dt snubbers are usually needed in high-power gate-turnoff (GTO) converters, the proposed topology offers a solution to the problem of snubber energy recovery. The control strategy explained in the paper allows both full-range PWM and minimization of stresses during the resonant commutation process. Results of a theoretical analysis and design criteria are reported in the paper. Examples of PWM control schemes are also described, both for analog (ramp-comparison-based) and digital (space-vector-based) implementations. Experimental results obtained from a small-size laboratory prototype are given.
<i>De Novo</i> Analysis of Peptide Tandem Mass Spectra by Spectral Graph Partitioning (2006)

We report on a new de novo peptide sequencing algorithm that uses spectral graph partitioning. In this approach, relationships between m/z peaks are represented by attractive and repulsive springs, and the vibrational modes of the spring system are used to infer information about the peaks (such as "likely b-ion" or "likely y-ion"). We demonstrate the effectiveness of this approach by comparison with other de novo sequencers on test sets of ion-trap and QTOF spectra, including spectra of mixtures of peptides. On all datasets, we outperform the other sequencers. Along with spectral graph theory techniques, the new de novo sequencer EigenMS incorporates another improvement of independent interest: robust statistical methods for recalibration of time-of-flight mass measurements. Robust recalibration greatly outperforms simple least-squares recalibration, achieving about three times the accuracy for one QTOF dataset.
Genetic Algorithm Applied to the Selection of Factors in Principal Component-Artificial Neural Networks:  Application to QSAR Study of Calcium Channel Antagonist Activity of 1,4-Dihydropyridines (Nifedipine Analogous) (2003)

A QSAR algorithm, principal component-genetic algorithm-artificial neural network (PC-GA-ANN), has been applied to a set of newly synthesized calcium channel blockers, which are of special interest because of their role in cardiac diseases. A data set of 124 1,4-dihydropyridines bearing different ester substituents at the C-3 and C-5 positions of the dihydropyridine ring and nitroimidazolyl, phenylimidazolyl, and methylsulfonylimidazolyl groups at the C-4 position with known Ca(2+) channel binding affinities was employed in this study. Ten different sets of descriptors (837 descriptors) were calculated for each molecule. The principal component analysis was used to compress the descriptor groups into principal components. The most significant descriptors of each set were selected and used as input for the ANN. The genetic algorithm (GA) was used for the selection of the best set of extracted principal components. A feed forward artificial neural network with a back-propagation of error algorithm was used to process the nonlinear relationship between the selected principal components and biological activity of the dihydropyridines. A comparison between PC-GA-ANN and routine PC-ANN shows that the first model yields better prediction ability.
SUSCEPTIBILITY OF MICRO-ORGANISMS TO CHLORAMPHENICOL (CHLOROMYCETIN) 12 (1949)

The antibiotic, chloramphenicol, produced by Streptomyces venezuelae, was originally reported by Ehrlich et al. (1, 2) and independently de- scribed by Carter, Gottlieb et al. (3, 4). Since these original reports the active principle has been chemically isolated and characterized (5, 6), syn- thesized (
Extracellular autoprocessing of a metalloprotease from Streptomyces cacaoi. (1992)

We have previously demonstrated that the extracellular neutral metalloprotease (Npr) of Streptomyces cacaoi is synthesized as a 60-kDa preproenzyme (P60), then processed to the 35-kDa mature form (P35) (Chang, P. C., Kuo, T.-C., Tsugita, A., and Lee, Y.-H. W. (1990) Gene (Amst.) 88, 87-95). In this study, we investigated the active site and the mechanism involved in the maturation of the protease. Site-specific mutations at the putative zinc-binding ligands and active site of Npr at His202, Glu203, His206, and Glu240 led to complete abolishment of Npr activity and concomitant accumulation of a 57-kDa inactive protein (P57) which was secreted. Sequence analysis of the NH2 terminus indicated that P57 was derived from P60 after removal of the signal peptide and represented the proenzyme form of Npr (pro-Npr). Analysis of the zinc content of purified mutant P57 proteins revealed a dramatic loss of zinc atom as compared with the wild-type P35 protein. In vitro with the aid of exogenous active Npr, the mutant P57 protein could be converted to the mature inactive P35 with an identical NH2-terminal sequence and a molecular mass the same as that of the wild-type P35. From these studies, we conclude that these highly conserved residues (His202, Glu203, His206, and Glu240) are indispensable for zinc binding and protease activity, as well as processing of Npr. In addition, we have clearly demonstrated that maturation of Npr occurs extracellularly via an autocatalytic cleavage of the pro-Npr propeptide. This is the first report of such a maturation mechanism for an extracellular protease in streptomycetes which can serve as a model for further studies on the mechanism of secretion and processing of proteases from Gram-positive bacteria.
Axonal Damage in Traumatic Brain Injury (2000)

Axonal damage is one of the most common and important pathologic features of traumatic brain injury. Severe diffuse axonal injury, resulting from inertial forces applied to the head, is associated with prolonged unconsciousness and poor outcome. The susceptibility of axons to mechanical injury appears to be due to both their viscoelastic properties and their highly organized structure in white matter tracts. Although axons are supple under normal conditions, they become brittle when exposed to rapid deformations associated with brain trauma. Accordingly, rapid stretch of axons can damage the axonal cytoskeleton, resulting in a loss of elasticity and impairment of axoplasmic transport. Subsequent swelling of the axon occurs in discrete bulb formations or in elongated varicosities that accumulate organelles. Calcium entry into damaged axons is thought to initiate further damage by the activation of proteases and the induction of mitochondrial swelling and dysfunction. Ultimately, swollen axons may become disconnected and contribute to additional neuropathologic changes in brain tissue. However, promising new therapies that reduce proteolytic activity or maintain mitochondrial integrity may attenuate progressive damage of injured axons following experimental brain trauma. Future advancements in the prevention and treatment of traumatic axonal injury will depend on our collective understanding of the relationship between the biomechanics and pathophysiology of various phases of axonal trauma.
A statistical wideband propagation model for smart antenna systems (2002)

Multiple antenna systems are promising architectures for overcoming the effects of multipath interference and increasing the spectrum efficiency. In order to be able to investigate these systems, a channel model is required which incorporates both the delays and arrival angles for outdoor environments. We propose a flexible and simple to implement propagation model. The statistical characteristics of the model parameters are developed, and the validity of the model is investigated by simulations which are compared with the measurement results.
Biomimetic CaCO<sub>3</sub> Mineralization using Designer Molecules and Interfaces (2008)

The whole range of organic-inorganic hybrid materials are generally molded into specifically designed devices with fascinating properties that are precisely controlled. The mimicking of the processes involved in biomineralization may provide new approaches to the fabrication of specialized organic-inorganic hybrid materials. Recently, researchers found that the control over polymorphism, crystallographic orientation, and crystal organization are paramount in determining the properties of hybrid materials. In this article, the biomimetic synthesis of calcium carbonate, the most abundant biomineral, has been the main focus.
Development of a Micro Total Analysis System Incorporating Chemiluminescence Detection and Application to Detection of Cancer Markers (2005)

We developed a micro total analysis system (mu-TAS) incorporating chemiluminescence detection, in which the chemiluminescence reaction of isoluminol isothiocyanato (ILITC) (as a chemiluminescence reagent for labeling)-microperoxidase (as a catalyst)-hydrogen peroxide (as an oxidant) was adopted. The analysis system performed the following three processes on a microchip: immune reaction for high selectivity, electrophoresis for formation and transportation of the sample plug, and chemiluminescence detection for high sensitivity. The three processes were compactly integrated onto the microchip to give the mu-TAS. The microchip contained two microchannels that crossed at an intersection, while the ends of the microchannels accessed four reservoirs. As the first process, the immune reaction was performed using an antibody-immobilized glass bead. The glass bead was placed in one of the reservoirs along with antigen (analyte) and a known amount of ILITC-labeled antigen to set up a competitive immune reaction. For electrophoresis, as the second process, the reactant after the immune reaction was fed electrophoretically into the intersection resulting in a sample plug. The sample plug was then moved into another reservoir containing hydrogen peroxide solution. At this point, chemiluminescence detection was performed as the third process: the labeled antigen mixed with the hydrogen peroxide and the catalyst included in the migration buffer to produce chemiluminescence. Chemiluminescence was detected by a photomultiplier tube located under the reservoir. The mu-TAS described here was capable of determining, with high selectivity and sensitivity, human serum albumin or immunosuppressive acidic protein as a cancer marker in human serum.
Advanced Asymmetric Supercapacitors Based on Ni(OH)<sub>2</sub>/Graphene and Porous Graphene Electrodes with High Energy Density (2012)

Abstract Hierarchical flowerlike nickel hydroxide decorated on graphene sheets has been prepared by a facile and cost‐effective microwave‐assisted method. In order to achieve high energy and power densities, a high‐voltage asymmetric supercapacitor is successfully fabricated using Ni(OH) 2 /graphene and porous graphene as the positive and negative electrodes, respectively. Because of their unique structure, both of these materials exhibit excellent electrochemical performances. The optimized asymmetric supercapacitor could be cycled reversibly in the high‐voltage region of 0–1.6 V and displays intriguing performances with a maximum specific capacitance of 218.4 F g −1 and high energy density of 77.8 Wh kg −1 . Furthermore, the Ni(OH) 2 /graphene//porous graphene supercapacitor device exhibits an excellent long cycle life along with 94.3% specific capacitance retained after 3000 cycles. These fascinating performances can be attributed to the high capacitance and the positive synergistic effects of the two electrodes. The impressive results presented here may pave the way for promising applications in high energy density storage systems.