gebhart/patrepeval huggingface dataset:
Step-Controlled Epitaxial Growth of α-Sic and Device Applications (1996)

In this thesis, chemical vapor deposition (CVD) of silicon carbide (SiC) on SiC{OOOl} substrates and device applications have been studied.Through recent progress in SiC growth techniques, SiC has been recognized as a vital wide bandgap material for high-power, high-frequency, high-temperature, and radia-tion-resistant devices, owing to its tremendous properties.SiC appears in a number of crystal structures with one-dimensional variation, so-called "polytypes" , which means that the polytype control during growth is crucial for device applications.For this purpose, polytype-controlled epitaxial growth of SiC, which utilizes step-flow growth on off-oriented SiC{OOOl} substrates (step-controlled epitaxy), is presented in this thesis.After detailed analyses on growth mechanism including surface kinetics, characterization of epilayers, impurity doping, and device applications are described.In Chapter 2, the outline of step-controlled epitaxy is described from a viewpoint of growth mode.Step-flow growth on off-oriented a-SiC{OOOI} substrates leads to homo epitaxy of a-SiC (step-controlled epitaxy), whereas two-dimensional nucleation results in the growth of 3C-SiC with double positioning twin.Low-temperature growth was attempted, and homoepitaxial growth of 6H-SiC could be achieved at temperatures as low as 1200C.In Chapter 3, growth mechanism in step-controlled epitaxy is discussed.The effects of growth temperature, off-angle, substrate polarity are described.Very little polarity dependence and small activation energy of growth rate (2.8kcaljmole) in step-controlled epitaxy can be explained by the fact that SiC growth is controlled by the diffusion of reactants in a stagnant layer.The step-bunching on the surfaces of 6H-and 4H-SiC epilayers is also investigated.Polarity and polytype dependences are discussed based on surface energy consideration.In Chapter 4, a model describing SiC growth on vicinal {OOOI} substrates is proposed based on a classical surface diffusion theory.Using the model and several experimental results, critical growth conditions where the growth mode changes from step-flow to two-dimensional nucleation are predict~d as a function of growth temperature, growth rate and substrate's off-angle.The obtained chart of growth condition will give a guideline for step-controlled
Executive coaching : strengths and thinking required (2006)

Extracted from text ... 62 Management Today August 2006 
Executive coaching: 
strengths and thinking required 
Bill Price is a master executive business 
and life coach. He specialises in coaching 
CEOs, executive teams and board 
directors in the implementation of their 
strategy with special emphasis on 
personal leadership competencies and 
capacity enhancement. He may be 
contacted at VIP Leadership and Strategic 
Coaching and Mentoring Institute 
and the Global Institute of Leading at 
(011) 918 2464. 
IIn management and leadership there still 
resides the reality of a fixation with fault 
finding and failure. In fact I am so aware 
that there are far more South African ..
Interleukin (IL)-4–independent Induction of Immunoglobulin (Ig)E, and Perturbation of  T Cell Development in Transgenic Mice Expressing IL-13 (1998)

Recent studies using interleukin (IL)-4-deficient animals have highlighted the existence of IL-4-independent immunoglobulin (Ig)E induction. We have established transgenic mice expressing IL-13 from a transgene comprising a genomic fragment containing the IL-13 gene and the human CD2 locus control region. The transgenes were expressed in lymphoid tissues and induced by T cell activators, suggesting regulation by elements of the IL-13 promoter. IL-13 transgenic lines expressed 10-100-fold higher levels of serum IgE than their littermate controls, but had normal levels of other serum Ig isotypes. Elevated IgE levels were also detected in sera from IL-4-deficient mice carrying IL-13 transgenes, indicating that IL-4 is not required for IL-13-induced IgE expression in the mouse. Expression of IL-13 also perturbed the development of thymocytes. Although thymocyte development was normal up to 4 wk of age, thymocyte number decreased dramatically thereafter, reaching 10% of normal by 10 wk, and despite normal size and appearance, histological examination demonstrated that transgenic thymi contained only small foci of thymocytes. The reduction in thymocyte number was due mainly to a depletion of CD4(+)CD8(+) thymocytes, and did not affect significantly the composition of peripheral T cell populations. These data indicate that expression of IL-13 transgenes in vivo can regulate IgE production in the mouse, and that IL-13 may also influence thymocyte development.
Cloning, sequence, and phenotypic expression of katA, which encodes the catalase of Lactobacillus sake LTH677 (1992)

Lactobacillus sake LTH677 is a strain, isolated from fermented sausage, which forms a heme-dependent catalase. This rare property is highly desirable in sausage fermentation, as it prevents rancidity and discoloration caused by hydrogen peroxide. A gene bank containing MboI fragments of chromosomal DNA from Lactobacillus sake LTH677 in Escherichia coli plasmid pBR328 was constructed. The catalase gene was cloned by heterologous complementation of the Kat- phenotype of E. coli UM2. The catalase structural gene, designated katA, was assigned to a 2.3-kb region by deletion analysis of the originally cloned fragment in plasmid pHK1000. The original chromosomal arrangement was determined by Southern hybridization. Protein analysis revealed that the catalase subunit has a molecular size of 65,000 Da and that the active catalase possesses a hexameric structure. The molecular size of the subunit deduced from the nucleotide sequence was determined to 54,504 Da. The N-terminal amino acid sequence of the 65,000-Da protein corresponded to the one deduced from the DNA sequence. After recloning of katA in the E. coli-Lactococcus shuttle vector pGKV210, the gene was successfully transferred and phenotypically expressed in Lactobacillus casei, which is naturally deficient in catalase activity.
The<i>Hermes</i>transposable element from the house fly,<i>Musca domestica</i>, is a short inverted repeat-type element of the<i>hobo, Ac</i>, and<i>Tam3</i>(<i>hAT</i>) element family (1994)

The genome of the house fly, Musca domestica, contains an active transposable element system, called Hermes. Using PCR and inverse PCR we amplified and sequenced overlapping segments of several Hermes elements and from these data we have constructed a 2749 bp consensus Hermes DNA sequence. Hermes termini are composed of 17 bp imperfect inverted repeats that are almost identical to the inverted terminal repeats of the hobo element of Drosophila melanogaster. Full length Hermes elements contain a single long ORF capable of encoding a protein of 612 amino acids which is 55% identical to the amino acid sequence of the hobo transposase. Comparison of the ends of the Hermes and hobo elements to those of the Ac element of Zea mays, and the Tam3 element of Antirrhinum majus, as well as several other plant and insect elements, revealed a conserved terminal sequence motif. Thus Hermes is clearly a member of the hobo, Ac and Tam3 (hAT) transposable element family, other members of which include the Tag1 element from Arabidopsis thaliana and the Bg element from Zea mays. The evolution of this class of transposable elements and the potential utility of Hermes as a genetic tool in M. domestica and related species are discussed.
Regulation of an Activated S6 Kinase 1 Variant Reveals a Novel Mammalian Target of Rapamycin Phosphorylation Site (2002)

A critical step in S6 kinase 1 (S6K1) activation is Thr(229) phosphorylation in the activation loop by the phosphoinositide-dependent protein kinase (PDK1). Thr(229) phosphorylation requires prior phosphorylation of the Ser/Thr-Pro sites in the autoinhibitory domain and Thr(389) in the linker domain, consistent with PDK1 more effectively catalyzing Thr(229) phosphorylation in a variant harboring acidic residues in these positions (S6K1-E389D(3)E). S6K1-E389D(3)E has high basal activity and exhibits partial resistance to rapamycin and wortmannin, and its activity can be further augmented by mitogens, effects presumably mediated by Thr(229) phosphorylation. However, PDK1-induced Thr(229) phosphorylation is reported to be constitutive rather than phosphatidylinositide 3,4,5-trisphosphate-dependent, suggesting that S6K1-E389D(3)E activity is mediated through a distinct site. Here we use phosphospecific antibodies to show that Thr(229) is fully phosphorylated in S6K1-E389D(3)E in the absence of mitogens and that regulation of S6K1-E389D(3)E activity by mitogens, rapamycin, or wortmannin parallels Ser(371) phosphorylation. Consistent with this observation, a dominant interfering allele of the mammalian target of rapamycin, mTOR, inhibits mitogen-induced Ser(371) phosphorylation and activation of S6K1-E389D(3)E, whereas wild type mTOR stimulates both responses. Moreover, in vitro mTOR directly phosphorylates Ser(371), and this event modulates Thr(389) phosphorylation by mTOR, compatible with earlier in vivo findings.
Optical dispersion relations for Si and Ge (1989)

A method is described for calculation of the optical constants (the refractive index, extinction coefficient, absorption coefficient, and normal-incidence reflectivity) of Si and Ge in the entire range of photon energies (0–0.6 eV). The imaginary part of the dielectric function [ε2(ω)] is derived first from the joint-density-of-states functions at energies of various critical points (CPs) in the Brillouin zone; then its real part [ε1(ω)] is obtained analytically using the Kramers–Kronig relation. The indirect-band-gap transitions are also assumed to provide a gradually increasing absorption spectrum expressed by a power law of (ℏω−EIDg)2, where ℏω is the photon energy and EIDg is the indirect-band-gap energy. The optical dispersion relations are expressed in terms of these model dielectric functions. The present model reveals distinct structures in the optical data at energies of the E0, E0+Δ0 [three-dimensional (3D) M0 critical point (CP)], E1, E1+Δ1 [3D M1 or two-dimensional (2D) M0 CP], E2 [a mixture of damped harmonic oscillator (DHO) and 2D M2 CP], E′0 triplet (DHO), and E1 (DHO). Calculated optical spectra are in satisfactory agreement with the experimental data over a wide range of the photon energies.
Synthetic Polyketide Enzymology: Platform for Biosynthesis of Antimicrobial Polyketides (2015)

Synthetic biology often employs enzymes in the biosynthesis of compounds for purposeful function. Here, we define synthetic enzymology as the application of enzymological principles in synthetic biology and describe its use as an enabling platform in synthetic biology for the purposeful production of compounds of biomedical and commercial importance. In particular, we demonstrated the use of synthetic polyketide enzymology as a means to develop lead polyketide based compounds for antimicrobial therapeutics, as exemplified by the modular coupling of acid:CoA ligases to type III polyketide synthases in the biosynthesis and development of polyketide-based biochemicals. Using wild-type and rationally designed mutants of a type III polyketide synthase isolated from Oryza sativa (OsPKS), we produced a chemically diverse library of novel polyketides and identified two bioactive antimicrobials, 4-hydroxy-6-[(1E)-2-(4-hydroxyphenyl)ethenyl]-2H-pyran-2-one (bisnoryangonin) and 3,6,7-trihydroxy-2-(4-methoxybenzyl)-4H-1-benzopyran-4,5,8-trione (26OH), respectively, from a screen against a collection of Gram-positive and Gram-negative bacteria. The purification, crystallization, and structural resolution of recombinant OsPKS at 1.93 Å resolution are also reported. Using the described route of synthetic polyketide enzymology, a library of OsPKS mutants was generated as an additional means to increase the diversity of the polyketide product library. We expect the utility of synthetic enzymology to be extended to other classes of biomolecules and translated to various purposeful functions as the field of synthetic biology progresses.
Hydrate Concept for Capturing Associated Gas (1998)

Abstract Natural gas hydrate (NGH) technology is an attractive alternative to capture associated gas on FPSO's to solve the stranded and marginal gas problem in the oil industry. Based on estimates for land-based plants, the capital cost of hydrate technology is considerably lower than LNG, methanol and syncrude technologies. Offshore-based hydrate plants are also expected to be lower in costs. Crude/hydrate slurry processes are being developed for use on FPSO's. NGH technology is safe, environmentally friendly and easily scaleable. P. 247
Cytoskeletal mechanics of proplatelet maturation and platelet release (2010)

Megakaryocytes generate platelets by remodeling their cytoplasm into long proplatelet extensions, which serve as assembly lines for platelet production. Although the mechanics of proplatelet elongation have been studied, the terminal steps of proplatelet maturation and platelet release remain poorly understood. To elucidate this process, released proplatelets were isolated, and their conversion into individual platelets was assessed. This enabled us to (a) define and quantify the different stages in platelet maturation, (b) identify a new intermediate stage in platelet production, the preplatelet, (c) delineate the cytoskeletal mechanics involved in preplatelet/proplatelet interconversion, and (d) model proplatelet fission and platelet release. Preplatelets are anucleate discoid particles 2-10 µm across that have the capacity to convert reversibly into elongated proplatelets by twisting microtubule-based forces that can be visualized in proplatelets expressing GFP-β1-tubulin. The release of platelets from the ends of proplatelets occurs at an increasing rate in time during culture, as larger proplatelets undergo successive fission, and is potentiated by shear.
Human Resistin Is a Systemic Immune-Derived Proinflammatory Cytokine Targeting both Leukocytes and Adipocytes (2006)

The characteristics of human resistin (RETN) are unclear and controversial despite intensive adipose-focused research. Its transcriptional and functional similarity with the murine myeloid-specific and CCAAT/enhancer binding protein epsilon (Cebpe)-dependent gene, resistin-like gamma (Retnlg), is unexplored. We examined the human CEBPE-regulatory pathway by unbiased reference and custom gene expression assays. Real-time RT-PCR analysis demonstrated lack of both the transcriptional factor CEBPE and RETN expression in adipose and muscle cells. In contrast, primary myelocytic samples revealed a concerted CEBPE-RETN transcription that was significantly elevated in inflammatory synoviocytes relative to intact peripheral blood mononuclear cells (PBMC). Mouse Cebpe and Retnlg were predictably expressed in macrophages, whereas Retn was abundant in adipocytes. Quite the opposite, a low and inconsistent RETN transcription was seen in some human white adipose tissue (WAT) biopsies without any relationship to body mass index, insulin sensitivity, or fat depot. However, in these cases, RETN was co-detected with CEBPE and the leukocyte-specific marker, EMR1, indicating the presence of inflammatory cells and their possible resistin-mediated effect on adipocytes. Indeed, addition of human resistin to WAT in culture induced, like in PBMC, the inflammatory cytokines IL6, IL8 and TNF. Importantly, the expression of the adipose-specific markers CEBPA, FABP4 and SLC2A4 was unchanged, while the expected inhibitory effect was seen with TNF. Both cytokines increased the mRNA level of CCL2 and MMP3, which may further promote inflammation in WAT. Thus, the myeloid-restricted nature of CEBPE precludes the expression of RETN in human adipocytes which, however, are targeted by this innate immune-derived proinflammatory cytokine.
New host cell system for regulated simian virus 40 DNA replication. (1985)

Transformed monkey cell lines (CMT and BMT) that inducible express simian virus 40 (SV40) T antigen from the metallothionein promoter have been isolated and characterized. Immunoprecipitation of pulse-labeled T antigen demonstrates a 5- to 12-fold increase in the rate of synthesis on addition of heavy-metal inducers to the culture medium. Radioimmunoassay of cell extracts indicates the accumulation of three- to fourfold more total T antigen after 2 days of induction by comparison with uninduced controls. A direct correlation was found between the level of T-antigen synthesis and the extent of SV40 DNA replication in inducible cells. Inducible BMT cells expressing a low basal level of T antigen were efficiently transformed by a vector carrying the neomycin resistance marker and an SV40 origin of replication. These vector sequences were maintained in an episomal form in most G418-resistant cell lines examined and persisted even in the absence of biochemical selection. Extensive rearrangements were observed only if the vector contained bacterial plasmid sequences. Expression of a protein product under the control of the SV40 late promoter in such vectors was increased after heavy-metal-dependent amplification of the template. These results demonstrate the ability of BMT cells to maintain a cloned eucaryotic gene in an amplifiable episomal state.
A FIELD TECHNIQUE FOR WEIGHING BEDLOAD SAMPLES1 (1984)

ABSTRACT: A technique for weighing bedload samples that was developed for laboratory use has been modified for field application. The technique involves determining the submerged weight of bedload samples as they are collected. The submerged weights are converted to dry weights from a knowledge of the specific gravity of the bedload material. The technique makes bedload transport data available immediately and eliminates costly and time‐consuming steps involved with saving samples for laboratory analysis. Only samples designated for particle‐size or other lab analyses need to be saved.
In-Situ Heat System Stimulates Paraffinic-Crude Producers in Gulf of Mexico (1989)

Summary A thermal stimulation process that generates downhole heat currently is being used to stimulate oil wells in the Gulf of Mexico. The crude produced from these shallow wells is highly paraffinic. Previous attempts to stimulate these wells with paraffin solvents and acid systems have been unsuccessful. The in-situ heat process has yielded 10-fold production rate increases and payout times of less than 1 week.
High frequency magnetic properties of some amorphous alloys (1981)

Amorphous magnetic alloys, although possessing low coercive forces and high electrical resistivities, have high-frequency losses significantly larger than expected from classical calculations. These high "anomalous" losses are caused by the wide domains in the material. This paper discusses some techniques for lowering the losses by changing the domain size in several amorphous alloy strips. Both DC and AC test (60 Hz, 1-10 kHz) results are reported. Transverse scratching, causing demagnetizing effects, lowered the loss, while longitudinal scratching had no effect. A transverse field during annealing led to a lower loss, as did annealing so that fine crystalline α-Fe precipitates were formed; such precipitates had a much stronger effect than did the induced magnetic anisotropy from field annealing. The application of a transverse DC bias field during testing at high frequency had a profound effect; losses decreased at low levels of bias field and increased at high levels. Application and removal of the bias field lowered the losses at high frequency as much as 40%. These bias fields were found to reduce the domain wall spacing. The observed effects are all consistent with the idea that domain refinement leads to a reduction in losses. Such processes can be used to improve the useful properties of amorphous alloys.
Structural and optical properties of coherent GaN islands grown on 6H-SiC(0001)-(√3×√3) (2003)

Coherent islands of GaN with base widths in the range of 100 to 500 nm were grown on 6H-SiC(0001)-(√3×√3) surfaces via the vapor–liquid–solid (VLS) mechanism. The microstructure of GaN islands was studied by high-resolution cross-sectional transmission electron microscopy. The morphological details of the islands were imaged by atomic force microscopy and the same assembly of islands was identified in a scanning electron microscope in which site-specific cathodoluminescence (CL) spectroscopy was conducted on individual islands. The broadening of the CL linewidths together with the shift to lower wave numbers in the E2 Raman mode detected by micro-Raman spectroscopy suggest the existence of tensile strain in the GaN islands. The strain is due to the heavy Si doping of the GaN islands by Si adatoms on the (√3×√3) substrate surface during the VLS growth process.
Applications of Foam Cement (1982)

ABSTRACT Foam cement offers a versatile and economical means of cementing wells with low density, high strength material. Several common applications of foam cement are available, and these include placing strong cement across weak or highly fractured zones without losing circulation; filling vugs or porous thief zones; or simply as an inexpensive light-weight filler slurry. The various aspects of slurry design, including their methods of determination, are discussed. It was found that thickening times could be determined directly on the foam cement in existing equipment with only minor modifications; the fluid loss and the rheology could be measured directly with no modifications; and the compressive strengths were determined in a special cell to prevent water invasion from the curing chamber. Since these parameters are determined by the nitrogen content, their relationships to density are also discussed. Job procedures for pumping foam cement are discussed in two methods, i.e., constant nitrogen rate (variable foam density) and constant density (variable nitrogen rate). Included in this discussion is the description of an improved atomizer for generating foam cement. From yard tests utilizing field equipment, it was found that this device improved the foam stability by means of better disbursement of the nitrogen in the cement slurry. The computer program which calculates the surface gas injection rates to achieve the desired density at specified depths is discussed and evaluated. Case histories are then presented to illustrate the effectiveness and versatility of foam cement as well as its relative ease of application. The case histories deal with repairing casing leaks and lost circulation problems in weak formations.
Adaptive intersection and t-threshold problems (2002)

Consider the problem of computing the intersection of k sorted sets. In the comparison model, we prove a new lower bound which depends on the non-deterministic complexity of the instance, and implies that the algorithm of Demaine, Lopez-Ortiz and Munro [2] is usually optimal in this adaptive sense. We extend the lower bound and the algorithm to the t-Threshold Problem, which consists in finding the elements which are in at least t of the k sets. These problems are motivated by boolean queries in text database systems.