gebhart/patrepeval huggingface dataset:
Characterization of DNA restriction and modification activities in Neisseria species (1987)

Type II restriction endonuclease activities detected in various Neisseria species were characterized for sequence specificity and precise site of cleavage. NsiCI isolated from N. sicca C351 cleaves the sequence 5′-GAT↓ATC-3′ (EcoRV isoschizomer); NmeCI from N. meningitidis C114 and NphI from N. pharyngis C245 cleave 5′-N↓GATCN-3′ (MboI isoschizomers); NgoPII and NgoPIII from N. gonorrhoeae P9-2 cleave at 5′-CC↓GCGG-3′ (SacII isoschizomer) and 5′-GG↓CC-3′ (HaeIII isoschizomer), respectively. Chromosomal DNA isolated from these strains and two other N. meningitidis strains (which lacked detectable endonuclease activities), was found to be refractive to cleavage by various restriction enzymes, implying the presence of methylase activities additional to those required for protection against the cellular endonucleases.
The effect of 1-alkene addition on hydrocarbon product distribution in Fischer-Tropsch synthesis on a cobalt catalyst (1991)

The cobalt-catalyzed reactions of C{sub 2}H{sub 4}, C{sub 3}H{sub 6}, or 1-C{sub 4}H{sub 8} added to synthesis gas in concentrations ranging from 0.5 to 1.2 mol. % of total feed were studied at 220{degrees}C, and 0.45 to 1.48 MPa. H{sub 2}/CO feed ratios were varied between 1.45 to 2.25 and H{sub 2} + CO conversions between 5 and 30% were observed. 1-Alkenes incorporate into growing chains on the catalyst surface, probably by initiating and/or terminating the chain growth process. Only ethene may propagate chain growth significantly. The propensity of the 1-alkenes to incorporate decreases with increasing carbon number of the 1-alkene and is affected by the extent of competitive reactions, notably hydrogenation to the alkene and isomerization to the 2-alkene. Incorporation is most evident in products above about C{sub 10}+. The double-{alpha} behavior exhibited by most Fischer-Tropsch catalysts can be interpreted as the sum of two growth processes, one a stepwise single-carbon growth process and the other a 1-alkene incorporation process. Many of the effects of process variables on the hydrocarbon selectivity of Fischer-Tropsch catalysts are consistent with this theory. 14 refs., 10 figs., 1 tab.
Physiology of the human body (1974)

The Cell Acquisition of Materials by Cells The Chemical Organization of the Cell Muscular Tissue The Brain The Cerebellum The Spinal Cord Sensory Functions of the Nervous System The Eye and Vision Body Fluids Acid-Base Balance of the Body Body Defenses Against Disease, Immunity, and the Blood Groups The Heart The Digestive System The Urinary System Interest Control-Biological Rhythms General References Appendix Glossary Index.
Photoelectronic Properties of Semiconductors (1992)

The interaction between light and electrons in semiconductors forms the basis for many interesting and practically significant properties. This book examines the fundamental physics underlying this rich complexity of photoelectronic properties of semiconductors, and will familiarise the reader with the relatively simple models that are useful in describing these fundamentals. The basic physics is also illustrated with typical recent examples of experimental data and observations. Following introductory material on the basic concepts, the book moves on to consider a wide range of phenomena, including photoconductivity, recombination effects, photoelectronic methods of defect analysis, photoeffects at grain boundaries, amorphous semiconductors, photovoltaic effects and photoeffects in quantum wells and superlattices. The author is Professor of Materials Science and Electrical Engineering at Stanford University, and has taught this material for many years. He is an experienced author, his earlier books having found wide acceptance and use. Readers will therefore find this volume to be an up-to-date and concise summary of the major concepts, models and results. It is intended as a text for graduate students, but will be an important resource for anyone researching in this interesting field.
Survival of Neural Stem Cells in the Cochlea (2001)

Adult rat hippocampus-derived neural stem cells (NSCs) have been reported to have been successfully grafted in several brain regions. To evaluate the possibility of treatment of sensorineural hearing loss using NSCs, survival of NSCs in the cochlea was estimated. NSCs were grafted into newborn rat cochleas. Within 2-4 weeks of grafting to the cochlea, some NSCs survived in the cochlear cavity. Some of them had adopted the morphologies and positions of hair cells. This suggests that NSCs can adapt to the environment of the cochlea and gives hope for treatment of the damaged cochlea and sensorineural hearing loss.
<title>Applying A Microprocessor-Controlled Spectral Radiometer System To Field Measurements</title> (1980)

Applying a spectral radiometer system to the broadest range of field measurements requires achieving maximum sensitivity and maximum spectral resolution over a broad band of wavelengths. A survey is made of methods of accomplishing this goal by conventional techniques and it is concluded that this requires the use of ponderous methods involving optical-mechanical control of the optical paths of multiple detectors and complex data processing to remove the effects of varying spectral sensitivity. The use of microprocessor control is surveyed and its application to specific radiometric processes is described in detail. Examples include the use of microprocessor control to switch the output of a sandwich radiation detector together with control of a spctral filter so as to use the most favorable detector-filter combinations. Also described is how the microprocessor makes possible automatic gain control, data sample averaging and data normalization to effectively remove the effects of the natural non-uniform spectral response of high-sensitivity detectors. The paper gives examples of the application of the radiometer to a reflectometer, transmissometer and other uses.
The guide to SQL Server (1990)

Microsoft's SQL Server unites client-server systems, relational databases and local area networks. This book, designed for application developers, technical managers, consultants and anyone who needs to know about relational database servers, tells how to use SQL Server to solve real-world business challenges. It teaches the fundamentals of relational databases, client-server technology and LANs, and details the architecture, features and operation of SQL Server. The book also discusses the specifics of server installation, data retrieval, security, data consistency and recovery, tuning and troubleshooting, and using Transact-SQL, SQL Server's programming language.
Aerodynamic performance of scale-model turbofan outlet guide vanes designed for low noise (2002)

The design of effective new technologies to reduce aircraft propulsion noise is dependent on an understanding of the noise sources and noise generation mechanisms in the modern turbofan engine. In order to more fully understand the physics of noise in a turbofan engine, a comprehensive aeroacoustic wind tunnel test programs was conducted called the 'Source Diagnostic Test.' The text was cooperative effort between NASA and General Electric Aircraft Engines, as part of the NASA Advanced Subsonic Technology Noise Reduction Program. A 1/5-scale model simulator representing the bypass stage of a current technology high bypass ratio turbofan engine was used in the test. The test article consisted of the bypass fan and outlet guide vanes in a flight-type nacelle. The fan used was a medium pressure ratio design with 22 individual, wide chord blades. Three outlet guide vane design configurations were investigated, representing a 54-vane radial Baseline configuration, a 26-vane radial, wide chord Low Count configuration and a 26-vane, wide chord Low Noise configuration with 30 deg of aft sweep. The test was conducted in the NASA Glenn Research Center 9 by 15-Foot Low Speed Wind Tunnel at velocities simulating the takeoff and approach phases of the aircraft flight envelope. The Source Diagnostic Test had several acoustic and aerodynamic technical objectives: (1) establish the performance of a scale model fan selected to represent the current technology turbofan product; (2) assess the performance of the fan stage with each of the three distinct outlet guide vane designs; (3) determine the effect of the outlet guide vane configuration on the fan baseline performance; and (4) conduct detailed flowfield diagnostic surveys, both acoustic and aerodynamic, to characterize and understand the noise generation mechanisms in a turbofan engine. This paper addresses the fan and stage aerodynamic performance results from the Source Diagnostic Test.
Catalytic Asymmetric [ 2,3 ] -Sigmatropic Rearrangement of Sulfur Ylides Generated from Carbenoids (2003)

The catalytic asymmetric reactions of oxygen or sulfur ylides generated from carbenoids have attracted consider able attention in recent years. High enantioselectivities have been achieved in the 1,3-dipolar cycloaddition reactions and [ 2,3 ]-sigmatropic rearrangement of oxygen ylides. In contrast to the oxygen ylide, the corresponding catalytic asymmetric reaction of sulfur ylide is less developed. Compared to oxygen ylides, the sulfur ylides are more stable and experimental evidence supports a free ylide rather than a metal-bound ylide as reaction intermediate. That means the enantio-control must be in the step of the ylide formation. If the subsequent reaction such as [ 2,3 ]-sigmatropic rearrangement or 1,3-dipolar cycloaddition is a concerted process and is faster than the racemization of the chiral ylide intermediate, then the catalytic asymmetric sulfur ylide reaction will be possible.……
Combining chromatin immunoprecipitation and DNA footprinting: a novel method to analyze protein-DNA interactions in vivo (2002)

A variety of methods are available to analyze protein-DNA interactions in vivo. Two of the most prominent of these methods are chromatin immunoprecipitation (ChIP) and in vivo footprinting. Both of these procedures have specific limitations. For example, the ChIP assay fails to document where exactly a protein binds in vivo. The precipitation of a specific segment of DNA with antibodies directed against DNA-binding proteins does not necessarily indicate that the protein directly interacts with a sequence in the precipitate but could rather reflect protein-protein interactions. Furthermore, the results of in vivo footprinting studies are inconclusive if a DNA sequence is analyzed that is bound by a specific protein in only a certain fraction of cells. Finally, in vivo footprinting does not indicate which protein is bound at a specific site. We have developed a new procedure that combines the ChIP assay and DMS footprinting techniques. Using this method we show here that antibodies specific for USF1 and NF-E2 precipitate the murine beta-globin promoter in MEL cells. DMS footprinting analysis of the DNA precipitated with NF-E2 antibodies revealed a protection over a partial NF-E2-binding site in the beta-globin downstream promoter region. We believe that this novel method will generally benefit investigators interested in analyzing protein-DNA interactions in vivo.
Camouflaging bacteria by wrapping with cell membranes (2019)

Bacteria have been extensively utilized for bioimaging, diagnosis and therapy given their unique characteristics including genetic manipulation, rapid proliferation and disease site targeting specificity. However, clinical translation of bacteria for these applications has been largely restricted by their unavoidable side effects and low treatment efficacies. Engineered bacteria for biomedical applications ideally need to generate only a low inflammatory response, show slow elimination by macrophages, low accumulation in normal organs, and almost unchanged inherent bioactivities. Here we describe a set of stealth bacteria, cell membrane coated bacteria (CMCB), meeting these requirement. Our findings are supported by evaluation in multiple mice models and ultimately demonstrate the potential of CMCB to serve as efficient tumor imaging agents. Stealth bacteria wrapped up with cell membranes have the potential for a myriad of bacterial-mediated biomedical applications.
A 4‐MV CT scanner for radiation therapy: The prototype system (1982)

A Varian 4-MV isocentric therapy accelerator has been modified to perform also as a CT scanner. The goal is to provide a computed tomography capability for use in radiotherapy at low cost. We envision three principal uses for the system. These are (i) to provide two and three-dimensional maps of electron density distribution for CT assisted therapy planning; (ii) to aid in patient set up by providing sectional views of the treatment volume and high contrast scout-mode verification images; and (iii) to provide a means for periodically checking the patients anatomical conformation against that which was used to generate the original therapy plan. The machine was modified by mounting an array of detectors on a frame that is bolted to the counterweight end of the gantry in such a manner as to define a "third generation" CT scanner geometry. Details of the detectors and data acquisition electronics are provided. We present results of phantom studies which demonstrate that this prototype system has a spatial resolution of 4 mm and the ability to discriminate electron density differences of less than 1%. We also show that the system is exactly linear over a wide range of electron densities corresponding to those found in body tissues.
Selective hydrolysis of chondroitin sulfates by hyaluronidase (1984)

Chondroitin 4-sulfate and chondroitin 6-sulfate were incubated with testicular hyaluronidase in the presence of excess beta-glucuronidase. The beta-glucuronidase caused rapid removal of the nonreducing terminal beta-D-glucuronosyl residues from the oligosaccharides formed by the action of the hyaluronidase, destroying the oligosaccharide acceptors required for the transglycosylation activity of hyaluronidase and releasing free D-glucuronic acid at a rate that was equal to the rate of the hyaluronidase-catalyzed hydrolysis. When hyaluronidase was assayed at 37 degrees C in the presence of 0.05 M NaCl, 0.05 M Na2SO4, and 0.1 M sodium acetate at pH 5, chondroitin 4-sulfate was hydrolyzed at 1.5 times the rate found for chondroitin 6-sulfate. When hyaluronidase was assayed at 45 degrees C in 0.06 M sodium acetate at pH 6, chondroitin 4-sulfate was hydrolyzed at 8 times the rate observed for chondroitin 6-sulfate. Under the pH5 conditions, the chondroitin 4-sulfate was converted to a mixture of tri- and pentasaccharides, while the chondroitin 6-sulfate was converted primarily to a mixture of penta- and heptasaccharides, with only a small amount of trisaccharide. Under the pH 6 conditions, the chondroitin 4-sulfate was converted to a mixture of penta- and heptasaccharides, with only a small amount of trisaccharide, but the products from chondroitin 6-sulfate were a mixture of oligosaccharides ranging in degree of polymerization from 7 to 25 monosaccharides per oligosaccharide. End-group analyses of the products formed at pH 6 showed that both substrates were cleaved preferentially at the glycosidic bonds of the 4-sulfated disaccharides.(ABSTRACT TRUNCATED AT 250 WORDS)
An Assessment of Commercial Motorcycle Transport Operators (CMTO) In Zaria Metropolis, Kaduna State (2011)

The presence and activities of Commercial Motorcycle Transport Operators (CMTO) is ubiquitous in Zaria metropolis and its growing effects fully felt. Consequently there is the need of a research focusing on its assessment. The aim of this study is to assess the activities of CMTO with a view to positively repositioning and regulating its activities for effectiveness. Accordingly, the researchers utilized primary data via the use of 250 questionnaires; collecting data on several research parameters relevant to this study. The study reveals that CMTO activities are indispensable in Zaria metropolis due to their significance in facilitating transportation activities in the study area. The study also shows that the number of people joining the business is on the increase and it is a readily available means of employment in the study area. Majority of the operators have experienced one form of accident or the other and expressed the view that the job is highly risky in nature due to fatal accidents that have led many operators to their premature graves. The study also highlighted some of the problems confronting the CMTO activities and proffered relevant workable solutions for ameliorating the problems.
Voltage-gated potassium channels in brown fat cells. (1989)

We studied the membrane currents of isolated cultured brown fat cells from neonatal rats using whole-cell and single-channel voltage-clamp recording. All brown fat cells that were recorded from had voltage-gated K currents as their predominant membrane current. No inward currents were seen in these experiments. The K currents of brown fat cells resemble the delayed rectifier currents of nerve and muscle cells. The channels were highly selective for K+, showing a 58-mV change in reversal potential for a 10-fold change in the external [K+]. Their selectivity was typical for K channels, with relative permeabilities of K+ greater than Rb+ greater than NH+4 much greater than Cs+, Na+. The K currents in brown adipocytes activated with a sigmoidal delay after depolarizations to membrane potentials positive to -50 mV. Activation was half maximal at a potential of -28 mV and did not require the presence of significant concentrations of internal calcium. Maximal voltage-activated K conductance averaged 20 nS in high external K+ solutions. The K currents inactivated slowly with sustained depolarization with time constants for the inactivation process on the order of hundreds of milliseconds to tens of seconds. The K channels had an average single-channel conductance of 9 pS and a channel density of approximately 1,000 channels/cell. The K current was blocked by tetraethylammonium or 4-aminopyridine with half maximal block occurring at concentrations of 1-2 mM for either blocker. K currents were unaffected by two blockers of Ca2+-activated K channels, charybdotoxin and apamin. Bath-applied norepinephrine did not affect the K currents or other membrane currents under our experimental conditions. These properties of the K channels indicate that they could produce an increase in the K+ permeability of the brown fat cell membrane during the depolarization that accompanies norepinephrine-stimulated thermogenesis, but that they do not contribute directly to the norepinephrine-induced depolarization.
A scalable CVD synthesis of high-purity single-walled carbon nanotubes with porous MgO as support material (2002)

The choice of support and catalyst materials has been proved to be critical to scalable chemical vapor deposition (CVD) synthesis of carbon nanotubes. In our study, we found that porous MgO prepared by thermal decomposition of its salts was an eminent support material for CVD growth of single-walled carbon nanotubes (SWNTs). Compared with other kinds of supports such as SiO2, ZrO2, Al2O3 and CaO etc., the quality of as-grown SWNTs on MgO supports was stable; the effects of reaction conditions such as furnace temperature, flow rate of the gas and the types of catalysts and supports on the properties of as-prepared SWNT products were thoroughly investigated and characterized by micro-Raman spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermogravimetry (TG) techniques. The results indicated that the yields of SWNTs on MgO supports could be up to about 120% with the addition of a small amount of assistant catalyst Mo salt. The obtained purity of the as-grown products was higher than 90% after treatment with 4 M HCl. The obvious advantages of using MgO supports include efficient and stable growth of SWNTs, scalable synthesis of SWNTs at low cost, and easy removal of the support in mild acid, causing little harm to the products.
Time-Hopping Multicarrier Code-Division Multiple Access (2007)

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A time-hopping multicarrier code-division multiple-access (TH/MC-CDMA) scheme is proposed and investigated. In the proposed TH/MC-CDMA, each information symbol is transmitted by a number of time-domain pulses with each time-domain pulse modulating a subcarrier. The transmitted information at the receiver is extracted from one of the, say, <formula formulatype="inline"><tex>$M$</tex></formula> possible time-slot positions, i.e., assuming that <formula formulatype="inline"><tex>$M$</tex></formula>-ary pulse-position modulation is employed. Specifically, in this paper, we concentrate on the scenarios such as system design, power spectral density (PSD) and single-user-based signal detection. The error performance of the TH/MC-CDMA system is investigated when each subcarrier signal experiences flat Nakagami-<formula formulatype="inline"><tex>$m$</tex></formula> fading in addition to additive white Gaussian noise. According to our analysis and results, it can be shown that the TH/MC-CDMA signal is capable of providing a near ideal PSD, which is flat over the system bandwidth available, while decreasing rapidly beyond that bandwidth. Explicitly, signals having this type of PSD are beneficial to both broadband and ultrawide-bandwidth communications. Furthermore, our results show that when optimum user address codes are employed, the single-user detector considered is near–far resistant, provided that the number of users supported by the system is lower than the number of subcarriers used for conveying an information symbol. </para>
Effects of Ta seed layer and annealing on magnetoresistance in CoFe∕Pd-based pseudo-spin-valves with perpendicular anisotropy (2007)

We have studied the switching characteristics and magnetoresistance of pseudo-spin-valves with perpendicular anisotropy based on CoFe∕Pd multilayers. In unpatterned thin films without exchange biasing, a maximum current-in-plane giant magnetoresistance of 7% was achieved, the highest reported to date in perpendicular pseudo-spin-valves. A Ta seed layer and the fcc (111) orientation of Pd was shown to be important in order to achieve good perpendicular anisotropy and sharp switching behavior. The improvement in perpendicular anisotropy and decay in magnetoresistance upon postdeposition annealing have been attributed to the formation of CoPd alloys at the CoFe∕Pd interfaces.
An Anthraquinone from<u>Cassia grandis</u>Linn (1994)

Abstract A new anthraquinone had been isolated from the pods of Cassia grandis Linn. and was identified as 1, 3, 4 -trihydroxy - 6, 7, 8 - trimethoxy - 2-methyl anthraquinone. The structure of this pigment was elucidated by chemical and spectroscopic methods and finally confirmed by its synthesis.