gebhart/patrepeval huggingface dataset:
Tautomeric pyridines. Part 22. The effect of intramolecular hydrogen bonding on the tautomeric structure of 4-amino-1,10-phenanthrolines (1978)

The tautomeric equilibria of 4-amino-1,10-phenanthroline, 4-amino-2,2′-bipyridyl, and certain of their N-substituted derivatives are assessed from pKa and u.v. spectral data. Comparison of pKT values for 4-amino-, and 4-anilino-1,10-phenanthroline with those for the corresponding pyridine derivatives indicates that in the former series a combination of intramolecular hydrogen bonding and destabilisation by lone pairs in close proximity reduces the predominance of the ‘amino’ tautomer by a factor of ca. 100.
Photon‐Upconverting Ionic Liquids: Effective Triplet Energy Migration in Contiguous Ionic Chromophore Arrays (2015)

Abstract Inspired by the bicontinuous ionic‐network structure of ionic liquids (ILs), we developed a new family of photofunctional ILs which show efficient triplet energy migration among contiguously arrayed ionic chromophores. A novel fluorescent IL, comprising an aromatic 9,10‐diphenylanthracene 2‐sulfonate anion and an alkylated phosphonium cation, showed pronounced interactions between chromophores, as revealed by its spectral properties. Upon dissolving a triplet sensitizer, the IL demonstrated photon upconversion based on triplet–triplet annihilation (TTA‐UC). Interestingly, the TTA‐UC process in the chromophoric IL was optimized at a much lower excitation intensity compared to the previous nonionic liquid TTA‐UC system. The superior TTA‐UC in this IL system is characterized by a relatively high triplet diffusion constant (1.63×10 −6 cm 2 s −1 ) which is ascribed to the presence of ionic chromophore networks in the IL.
Downhole Vibration Monitoring & Control System (2007)

The objective of this program is to develop a system to both monitor the vibration of a bottomhole assembly, and to adjust the properties of an active damper in response to these measured vibrations. Phase I of this program, which entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype, was completed on May 31, 2004. The principal objectives of Phase II were: more extensive laboratory testing, including the evaluation of different feedback algorithms for control of the damper; design and manufacture of a field prototype system; and, testing of the field prototype in a drilling laboratory. Phase II concluded on January 31, 2006, and the Phase II final report was issued. Work on Phase III of the project began during the first quarter, 2006. Efforts the current quarter have continued to focus on the manufacture of the prototype and precommercial parts, field test planning and commercialization. The continued extreme lead times quoted by oilfield machine shops for collar components significantly delayed the deployment of the prototype and precommercial units. All parts have now been received for two units, and all but one for the third. Mechanical assembly of the first two systems is complete and the electronics installation and laboratory testing will be finished in April. We have entered into a Memorandum of Understanding with a major US oilfield equipment supplier, which calls for their assisting with our field tests, in cash and in kind. We are close to signing a definitive agreement which includes the purchase of the three precommercial units. We had also signed a CRADA with the Rocky Mountain Oilfield Test Center (RMOTC), and scheduled a test at their site, The RMOTC drilling schedule continues to slip, and the test cannot begin until the first week of May. Based on these factors, we have requested a no-cost extension to July 31, 2007.
[Genetic control of the RecF recombination pathway. II. Effect of recL- and uvrE- mutations]. (1976)

It was found earlier that the effect of the uvrE- mutation on the yield of recombinants formed via RecF pathway of recombination was mainly due to the decreased viability of the recB-C-sbcB-uvrE- recipient. The results of the present paper show the uvrE- and recL- mutations reduce the recipient ability of the recB-C- sbcB- strains to the same extent. We were unable to find any evidence for complementation between the recL- and uvrE- mutations in transient as well as in stable uvrE-/recL- merozygotes. The recL152 as well as the uvrE502 mutation is lethal for the strains deficient in DNA polymerase I. Both recL- and uvrE- mutations reduce in the recB-C- sbcB- strains the probability of inheritance of the proximal non-selective donor markers as well as selective markers located close to the leading end of the donor chromosome. The former effect however could not be completely due to the latter.
The influence of land use, soils and topography on the delivery of hillslope runoff to channels in SE Spain (2002)

Abstract It is generally accepted that within particular physiographic and climatic regions catchments exhibit differences in their hydrological response. These differences result from the interaction of spatial variability in catchment characteristics, variability of rainfall inputs and surface and subsurface hydrological processes. These interactions are complex and difficult to unravel. Hydrologically similar surfaces (HYSS) have been used to identify catchment areas that have a similar response to rainfall and have been identified at a number of scales. HYSS have been identified at the subcatchment scale for the Rambla de Nogalte in SE Spain. Areas with similar at‐a‐point hydrological storages were distinguished by using a combination of geology, land use and topography. This mapping was compared with discharge estimates made throughout the catchment following a seven‐year return interval flood in September 1997. From this significant flood source areas were identified from reaches showing rapidly increasing channel discharge, and associated with HYSS that combined suitable internal characteristics with good connectivity to the main channel. This paper presents a simulation model that has been developed to investigate the way in which the hydrological response of areas within a HYSS respond to changes in source area, gradient, connectivity to the channel, storm size and intensity profile. This is one of the first studies using a hillslope model to investigate spatial patterns of runoff‐response in semi‐arid areas and results have implications for scaling up hydrological response, and on how the dynamics of runoff producing areas vary both under changing storm conditions and over time. It is implicit in our results that the nature of stream–slope coupling differs substantively between semi‐arid and humid areas. Copyright © 2002 John Wiley & Sons, Ltd.
Firearms: A Global History to 1700 (2003)

This book is a history of firearms across the world from the 1100s up to the 1700s, from their invention in China to the time when European firearms had become clearly superior. It asks why it was the Europeans who perfected firearms when it was the Chinese who had invented them, and answers this question by looking at how firearms were used throughout the world. Early firearms were restricted to infantry and siege warfare, limiting their use outside of Europe and Japan. Steppe and desert nomads imposed a different style of warfare on the Middle East, India, and China – a style with which firearms were incompatible. By the time that better firearms allowed these regions to turn the tables on the nomads, Japan's self-imposed isolation left Europe with no rival in firearms design, production, or use, with consequences that are still with us today
Designing Star Trackers to Meet Micro-Satellite Requirements (2006)

** Star tracke rs provide numerous advantages over other attitude sensors because of their flexibility to operate independently from other navigation tools and their ability to provide full three -axis orientation information with high accuracy. However, current star tra ckers are optimized to maximize accuracy, at the exclusion of all else. A lthough this produces extremely capable systems, the lofty mass, power consum ption, and cost that result are often contradictory to the requirements of smaller space vehicles. Thus, it is of interest to design smaller, lower cost, a lbeit reduced capability star trackers that can provide adequate attitude and rate determination to small, highly m aneuverable, low -cost spacecraft. To meet physical requirements, appropriate constraints on memory, computational speed, and optics must been defined and included in the hardware selection and software design. The primary sof tware algorithms must include functions to extract and centroid stars from image noise and to match star patterns betwe en subsequent i mages or to a small on -board catalog. Multiple pattern matching alg orithms can be implemented in a dynamic manner based on the number of stars present in the image and whether or not current rate information is available. This pr ovides sev eral modes of operation and graceful degrad ation of performance at higher angular rates . The algorithms used incorporate various aspects from open literature, but include appropriate modifications and improvements where applicable. Thresholding at low si gnal -to -noise ratios is acco mplished via a statistical pre -filter to address high noise content. Centroiding examines the stellar shape to optimally set the aperture shutter time for different rotation rates. Pattern matching between frames implements a ‘smart’ star selection technique to avoid wasted time on stars that might not appear in both images. A n n-vertex pattern match is performed against a star catalog that has been reduced either based on the probability that the stars would be used or by exi sting attitude i nformation. Finally, quaternion s olutions are generated using a recursive estimation technique. This paper discusses the analysis used to select hardware and predict system performance, as well as the a lgorithms that have been employed to determine attitude information and rotation rates of the spacecraft . The performance of these
Evidence for a Direct Link between Glutathione Biosynthesis and Stress Defense Gene Expression in Arabidopsis[W] (2004)

The mutant regulator of APX2 1-1 (rax1-1) was identified in Arabidopsis thaliana that constitutively expressed normally photooxidative stress-inducible ASCORBATE PEROXIDASE2 (APX2) and had >/=50% lowered foliar glutathione levels. Mapping revealed that rax1-1 is an allele of gamma-GLUTAMYLCYSTEINE SYNTHETASE 1 (GSH1), which encodes chloroplastic gamma-glutamylcysteine synthetase, the controlling step of glutathione biosynthesis. By comparison of rax1-1 with the GSH1 mutant cadmium hypersensitive 2, the expression of 32 stress-responsive genes was shown to be responsive to changed glutathione metabolism. Under photo-oxidative stress conditions, the expression of a wider set of defense-related genes was altered in the mutants. In wild-type plants, glutathione metabolism may play a key role in determining the degree of expression of defense genes controlled by several signaling pathways both before and during stress. This control may reflect the physiological state of the plant at the time of the onset of an environmental challenge and suggests that changes in glutathione metabolism may be one means of integrating the function of several signaling pathways.
Cellular Pharmacology of the<scp>D</scp>- and<scp>L</scp>-Enantiomers of β-5-<i>o</i>-Carboranyl-2′-deoxyuridine (2000)

The cellular pharmacology of the D- and L-enantiomers of beta-5-o-carboranyl-2'-deoxyuridine (CDU), compounds designed for boron neutron capture therapy (BNCT), were studied using human CEM lymphoblast and U-251 glioblastoma cells, at a physiologically achievable concentration (1 microM). Accumulation of the enantiomers was rapid and indistinguishable, reaching cellular concentrations > 40-fold higher than extracellular levels, with approximately 5% persisting in cells after incubation in fresh medium for more than 2 hr. Uptake was not affected by nucleoside uptake inhibitors, but was inhibited by the purine base uptake inhibitor papaverine.
The Potential for Energy-aware User Interfaces on Handheld Devices (2003)

The utility of a handheld device is often constrained by the battery life, particularly with recent usage patterns where the device is likely to be powered on at all times. The display component in these devices is a major consumer of battery energy and reducing its energy consumption can significantly enhance its utility. This primary research explores the impact of emerging technologies that provide energy-saving display modifications on perceived ease of use, quality, and overall user acceptance, and seeks to understand the tradeoffs between energy reduction and user acceptance for future interfaces. For our study, twelve handheld users reviewed energy-adaptive and standard display interfaces during five scenarios representing frequently performed tasks. The results show good acceptance of energy-aware user interfaces. While displays for tasks involving notifications and menus were deemed acceptable, primarily due to enhanced contrast levels, displays for longer tasks involving greater informational context need additional work.
New Drug Targets for HIV (2005)

A significant number of human immunodeficiency virus (HIV) infections have become resistant to antiretroviral treatment, which means that there is a paramount need for novel drug targets to defeat the virus. Until recently, all HIV drugs inhibited HIV replication by mechanisms operating inside infected cells. In contrast, new antiretroviral drugs operate outside infected cells. Their mechanism of action consists in inhibiting entry of the virus into cells, thereby halting the very first step of HIV replication. Examples of this new class of drugs include entry inhibitors, coreceptor antagonists, and fusion inhibitors. In addition to their novel mechanism of action, this new class of drugs also has potential action against drug-resistant HIV strains, causes minimal adverse effects, and may be administered in a simplified, once-daily dosing regimen. New classes of anti-HIV drugs--and new drugs in existing classes--represent the best hope for people infected with HIV, especially those who have exhausted current therapies.
Self-tuning control algorithm for single-chip microcomputer implementation (1983)

The paper describes the development of an adaptive regulator which is suitable for low-cost consumer control applications where single-chip microcomputer implementation is necessary. The regulator, which is derived by simplification of the well known generalised minimum-variance self-tuning controller, uses a variable forgetting-factor stochastic approximation variant of the recursive least-squares parameter estimator. Results obtained by digital simulation are used to compare the performance of the adaptive regulator to that of the full UD-filter implementation of the self-tuning controller and to that of a limited precision integer arithmetic version of the simplified self tuner. Practical results are also presented to illustrate the behaviour of the regulator when implemented on a commercially available single-chip microcomputer and controlling a real system.
c-Jun N-Terminal Kinase 1 Is Required for the Development of Pulmonary Fibrosis (2008)

Collagen deposition is observed in a diverse set of pulmonary diseases, and the unraveling of the molecular signaling pathways that facilitate collagen deposition represents an ongoing area of investigation. The stress-activated protein kinase, c-Jun N-terminal kinase 1 (JNK1), is activated by a large variety of cellular stresses and environmental insults. Recent work from our laboratory demonstrated the critical role of JNK1 in epithelial to mesenchymal transition. The goal of the present study was to examine the involvement of JNK1 in subepithelial collagen deposition in mice subjected to models of allergic airways disease and interstitial pulmonary fibrosis. Activation of JNK was slightly enhanced in lungs from mice subjected to sensitization and challenge with ovalbumin (Ova), and predominant localization of phospho-JNK was observed in the bronchial epithelium. While mice lacking JNK1 (JNK1-/- mice) displayed enhanced lung inflammation and cytokine production compared with wild-type (WT) mice, JNK1-/- mice accumulated less subepithelial collagen deposition in response to antigen, and showed decreased expression of profibrotic genes compared with WT animals. Furthermore, transforming growth factor (TGF)-beta1 content in the bronchoalveolar lavage was diminished in JNK1-/- mice compared with WT animals subjected to antigen. Finally, we demonstrated that mice lacking JNK1 were protected against TGF-beta1 and bleomycin-induced pro-fibrotic gene expression and pulmonary fibrosis. Collectively, these findings demonstrate an important requirement for JNK1 in promoting collagen deposition in multiple models of fibrosis.
Structure and parameter learning via entropy minimization, with applications to mixture and hidden Markov models (1999)

We develop a computationally efficient framework for finding compact and highly accurate hidden-variable models via entropy minimization. The main results are: (1) an entropic prior that favors small, unambiguous, maximally structured models. (2) A prior balancing manipulation of Bayes' rule that allows one to gradually introduce or remove constraints in the course of iterative reestimation. (1) and (2) combined give the information-theoretic free energy of the model and the means to manipulate it. (3) Maximum a posteriori (MAP) estimators such that entropy optimization and deterministic annealing can be performed wholly within expectation maximization (EM). (4) Trimming tests that identify excess parameters whose removal will increase the posterior, thereby simplifying the model and preventing over-fitting. The end result is a fast and exact hill-climbing algorithm that mixes continuous and combinatoric optimization and evades sub-optimal equilibria. Examples are given using speech and language problems.
Step-In Mode NC-AFM Using a Quadrature Frequency Demodulator for Observing High-Aspect Ratio Structures in Air (2011)

We have investigated step-in mode non-contact atomic force microscopy (NC-AFM) for precise measurement of fine and steep structures having high aspect ratios. We have proposed piconewton controlled step-in mode AFM using NC-AFM to suppress bending and slipping of the probe on a slope. We have constructed a prototype of the step-in mode NC-AFM using a quadrature frequency demodulator for detecting the resonant frequency shift of the cantilever. Experiments revealed that the system was able to perform step-in mode NC-AFM even in air. We obtained a faithful AFM image of the steep structure of a dry-etched Si pattern without bending or slipping of the probe at approximately 2-3 pN using a sharp, slim probe, as compared with a step-in mode contact AFM image obtained at 1, 5, and 10 nN. [DOI: 10.1380/ejssnt.2011.122]
The effects of microstructure on the electrocaloric properties of Pb(Zr,Sn,Ti)O <sub>3</sub> ceramics (1981)

Abstract When an electric field is applied to a dielectric material under adiabatic conditions there is a resultant change in temperature, a phenomenon known as the electrocaloric effect. Compositions in the Pb(Zr,Sn,Ti)O3 system (PZST) have several phases of nearly equal free energy, allowing antiferroelectric (AFE) to ferroelectric (FE) and paraelectric (PE) to ferroelectric (FE) transitions to occur. Data are presented for electrocaloric measurements on AFE materials in the vicinity of the Curie point. The effect of microstructure is reported, and experimental values are related to dielectric properties through thermodynamic relations. Culmination of this work resulted in the largest electrocaloric effect (2.6°K) measured to date for coarse grain material in the PZST system.
β-Amino acid derived gemini surfactants from diformylfuran (DFF) with particularly low critical micelle concentration (CMC) (2017)

Starting from diformylfuran (DFF) obtained from biomass, a new family of gemini surfactants has been synthesized.
Studies on pyrimidine derivatives. XXVIII. Synthesis of pyridopyrimidine derivatives by cross-coupling of halopyrimidines with olefins and acetylenes. (1982)

Three kinds of pyridopyrimidines were synthesized from appropriate pyrimidine derivatives. Cross-coupling of 4-amino-5-iodopyrimidines with α, β-unsaturated carboxylic esters followed by ring-closure afforded pyrido [2, 3-d] pyrimidines. Ammonolysis of 4-ethoxycarbonyl-5-phenylethynyl-and 5-ethoxycarbonyl-4-phenyl-ethynyl-pyrimidines which were obtained by cross-coupling of the corresponding halopyrimidines with phenylacetylene, gave pyrido [3, 4-d]-and pyrido [4, 3-d]-pyrimidines, respectively.
Multiresolution Color Image Segmentation Applied to Background Extraction in Outdoor Images (2002)

An adaptive technique for color image segmentation is presented in this paper. The segmentation is performed using a multiresolution scheme and considering the background areas have quite uniform color features at a low-resolution representation of the image. First, a pyramidal representation of the original image is built. Then segmentation is improved iteratively at each resolution using color information. This method allows to extract background areas in outdoor images. Background and foreground separation is especially useful in initialization of object tracking applications. Several color spaces are compared in order to determine a robust method specially with respect to illumination changes which frequently occur in outdoor images. Mean value of Hue component from HSV (Hue, Saturation, Value) color space is selected as the best decision criterion for image matching. Segmentation results of color image from soccer game video sequences are presented to illustrate the method efficiency.
Linear Accuracy and Reliability of Cone Beam CT Derived 3-Dimensional Images Constructed Using an Orthodontic Volumetric Rendering Program (2007)

While many linear measurements between cephalometric landmarks on 3D volumetric surface renderings obtained using Dolphin 3D software generated from CBCT datasets may be statistically significantly different from anatomic dimensions, most can be considered to be sufficiently clinically accurate for craniofacial analyses.
CXCL12/SDF-1 and CXCR4 (2015)

Chemokines are a large family of structurally related chemoattractive cytokines, which have four conserved cysteines forming two disulfide bonds, and act through seven-transmembranespanning receptors coupled to heterotrimeric GTP-binding proteins (G-protein-coupled receptors). Chemokines were thought to be signaling molecules that attract leukocytes to sites of inflammation; however, CXC chemokine ligand (CXCL)12 [also known as stromal cell-derived factor (SDF)-1 and pre-B-cell-growth-stimulating factor (PBSF)] is the first member that was shown to be critical for developmental processes, including hematopoiesis (1), cardiogenesis (1-3), vascular formation (2), and neurogenesis (3), as well as the maintenance of tissue stem cells (4).
Atomic Layer Deposition on Electrospun Polymer Fibers as a Direct Route to Al<sub>2</sub>O<sub>3</sub> Microtubes with Precise Wall Thickness Control (2007)

Atomic layer deposition (ALD) of Al2O3 on electrospun poly(vinyl alcohol) microfiber templates is demonstrated as an effective and robust strategy by which to fabricate long and uniform metal-oxide microtubes. The wall thickness is shown to be precisely controlled within a molecular layer or so by adjusting the number of ALD cycles utilized. By judicious selection of the electrospinning and ALD parameters, designer tubes of various sizes and inorganic materials can be synthesized.