gebhart/patrepeval huggingface dataset:
Synthesis of Pyranopyrans Related to Diplopyrone and Evaluation as Antibacterials and Herbicides (2020)

Stereoselective syntheses of new pyranopyrans that are related to the natural product diplopyrone, which is a phytotoxin implicated in cork oak decline, have been achieved from carbohydrate starting materials in two approaches that are based on <i>C</i>-glycosides as key intermediates. A <i>C</i>-alkynyl glycoside prepared by Ferrier rearrangement was used as the precursor to a new pyranopyran alkyne that showed potent antibacterial activity against the common bacterial pathogen <i>Edwardsiella ictaluri</i> that causes enteric septicemia in catfish. The <i>C</i>-alkynyl glycoside also showed herbicidal activity. New bioassay data for the pyranopyran nitrile (4a<i>R</i>,6<i>S</i>,8a<i>R</i>)-6-cyano-6,8a-dihydropyrano-[3,2-<i>b</i>]pyran-2(4a<i>H</i>)-one, the most potent of the pyranopyrans synthesized to date, were obtained in greenhouse studies that revealed additional herbicidal activity. Other new analogues that were synthesized included desmethylpyranopyrans that were prepared by Isobe <i>C</i>-alkynylation-rearrangement/reduction and RCM-based pyranopyran construction. The antibiotic and phytotoxic activities of the new pyranopyrans synthesized in this study highlight the importance of substituents on the nonlactone ring and demonstrate the potential of such compounds as antibiotics and herbicides.
Analysis of the Decaprenyl Diphosphate Synthase (dps) Gene in Fission Yeast Suggests a Role of Ubiquinone as an Antioxidant (1997)

Schizosaccharomyces pombe produces ubiquinone-10 whose side chain is thought to be provided by the product generated by decaprenyl diphosphate synthase. To understand the mechanism of ubiquinone biosynthesis in S. pombe, we have cloned the gene encoding decaprenyl diphosphate synthase by the combination of PCR amplification of the fragment and subsequent library screening. The determined DNA sequence of the cloned gene, called dps, revealed that the dps gene encodes a 378-amino-acid protein that has the typical conserved regions observed in many polyprenyl diphosphate synthases. Computer-assisted homology search indicated that Dps is 45 and 33% identical with hexaprenyl diphosphate synthase from Saccharomyces cerevisiae and octaprenyl diphosphate synthase from Escherichia coli, respectively. An S. pombe dps-deficient strain was constructed. This disruptant was not able to synthesize ubiquinone and had no detectable decaprenyl diphosphate synthase activity, indicating that the dps gene is unique and responsible for ubiquinone biosynthesis. The S. pombe dps-deficient strain could not grow on either rich medium supplemented with glycerol or on minimal medium supplemented with glucose. The dps-deficient strain required cysteine or glutathione for full growth on the minimal medium. In addition, the dps-deficient strain is more sensitive to H2O2 and Cu2+ than the wild type. These results suggests a role of ubiquinone as an antioxidant in fission yeast cells.
Flattened dispersion in silicon slot waveguides (2010)

We propose a silicon strip/slot hybrid waveguide that produces flattened dispersion of 0 ± 16 ps/(nm∙km), over a 553-nm wavelength range, which is 20 times flatter than previous results. Different from previously reported slot waveguides, the strip/slot hybrid waveguide employs the mode transition from a strip mode to a slot mode to introduce unique waveguide dispersion. The flat dispersion profile is featured by three zero-dispersion wavelengths, which is obtained for the first time in on-chip silicon waveguides, to the best of our knowledge. The waveguide exhibits flattened dispersion from 1562-nm to 2115-nm wavelength, which is potentially useful for both telecom and mid-infrared applications.
DOWNHOLE VISCOSITY MEASUREMENT: REVEALING RESERVOIR FLUID COMPLEXITIES AND ARCHITECTURE (2014)

Knowledge of formation fluid viscosity and its vertical and lateral variations are important for reservoir management and determining field commerciality. Productivity and fluid displacement efficiency are directly related to fluid mobility, which, in turn, is greatly influenced by fluid viscosity. Therefore, viscosity is a critical parameter for estimating the economic value of a hydrocarbon reservoir and also for analyzing compositional gradients and vertical and horizontal reservoir connectivity. The conventional methods for obtaining formation fluid viscosity are laboratory analysis at surface and pressure/volume/temperature (PVT) correlations. However, deducing viscosity from correlations introduces uncertainties owing to the inherent assumptions. Surface viscosity measurement may be affected by irreversible alteration of the sampled fluid through pressure and temperature changes, as well as related effects of long-term sample storage. A new downhole sensor for a wireline formation tester tool has been introduced to measure the viscosity of hydrocarbons. The new viscosity sensor uses a vibrating-wire (VW) measurement method with wellestablished analytical equations for interpretation. Downhole field testing of an experimental prototype has been conducted, with extensive laboratory tests to validate the sensor performance in viscosities ranging from light to heavy oil and at a wide range of well environments. The vibrating wire viscometer sensor meets requirements not only for measurement performance, but also for operations in downhole applications, and possesses the following properties:  High-pressure and high-temperature qualification (25,000 psi and 347° F)  Fast response time with an accurate viscosity measurement provided every second  Installation in standard downhole fluid analyzer modules in wireline formation testers, made possible by recent miniaturization  Deployment in sections with immiscible contamination  Accurate temperature measurement of flowing fluid
Noncoherent Approach for Through-the-Wall Moving Target Indication (2014)

A moving target indication, noncoherent change detection algorithm is introduced to detect moving targets inside buildings. The proposed algorithm is designed to attenuate image artifacts observed in coherent change detection images by utilizing noncoherent change detection, a positive threshold operation, and sidelobe minimization. The proposed algorithm is compared with coherent change detection for three moving target scenarios. It is shown that the proposed algorithm significantly reduces imaging artifacts while preserving the moving target signature.
Towards a shared large-area mixed reality system (2016)

In this paper we present a large-area interactive mixed reality system where multiple users can experience an event simultaneously. Through the combination of a number of innovative methods, the system can tackle common problems that are inherent in most existing mixed reality solutions, such as robustness against lighting conditions, static occlusion, illumination correction, registration and tracking etc. Most importantly, with our proposed experience server, a shared event among multiple users is seamless. The experience server tracks every user's position and experience state and presents a unique viewpoint of the event to multiple users simultaneously. The effectiveness of the system is demonstrated through an example application at a heritage site, where we perform user testing through multiple focus groups.
Effects of Geometry of Ring Spinning Triangle on Yarn Torque: Part II: Distribution of Fiber Tension within a Yarn and Its Effects on Yarn Residual Torque (2009)

This paper presents a theoretical analysis of fiber tension distribution within a ring spun yarn without relaxation. Yarn residual torque is determined on the basis of the translation of fiber tension at the spinning triangle, as presented in the first part of this series of papers, into the fiber tension within the yarn. The results from numerical simulations indicate that, with fiber buckling, the yarn exhibits a lower average fiber tension and, thus, a much reduced yarn residual torque than that without fiber buckling. Comparison with experiments confirmed that fiber buckling exists in ring yarns while the assumption of no fiber buckling is not realistic. Generally, a low yarn twist results in low average fiber tension in the yarn and, thus, a reduced yarn residual torque. A symmetrical spinning triangle leads to a slightly higher yarn residual torque than a right-angle spinning triangle when the yarn counts and twists are identical and fiber buckling occurs.
Identification of a Specific Domain Required for Dimerization of Activation-induced Cytidine Deaminase (2006)

Activation-induced cytidine deaminase (AID) is essential to all three genetic alterations required for generation of antigen-specific immunoglobulin: class switch recombination, somatic hypermutation, and gene conversion. Here we demonstrate that AID molecules form a homodimer autonomously in the absence of RNA, DNA, other cofactors, or post-translational modifications. Studies on serial deletion mutants revealed the minimum region between Thr27 and His56 responsible for dimerization. Analyses of point mutations within this region revealed that the residues between Gly47 and Gly54 are most important for the dimer formation. Functional analyses of these mutations indicate that all mutations impairing the dimer formation are inefficient for class switching, suggesting that dimer formation is required for class switching activity. Dimer formation and its requirement for the function of AID are features that AID shares with APOBEC-1, an RNA editing enzyme of apolipoprotein B100 mRNA.
Development of a Catalytic Combustor for a Heavy-Duty Utility Gas Turbine (1996)

The most effective technologies currently available for controlling NOx emissions from heavy-duty industrial gas turbines are either diluent injection in the combustor reaction zone, or lean premixed Dry Low NOx (DLN) combustion. For ultra low emissions requirements, these must be combined with selective catalytic reduction (SCR) DeNOx systems in the gas turbine exhaust. An alternative technology for achieving comparable emissions levels with the potential for lower capital investment and operating cost is catalytic combustion of lean premixed fuel and air within the gas turbine. The design of a catalytic combustion system using natural gas fuel has been prepared for the GE model MS9OOIE gas turbine. This machine has a turbine inlet temperature to the first rotating stage of over 1100°C and produces approximately 105 MW electrical output in simple cycle operation. The 508 mm diameter catalytic combustor designed for this gas turbine was operated at full-scale conditions in tests conducted in 1992 and 1994. The combustor was operated for twelve hours during the 1994 test and demonstrated very low NOx emissions from the catalytic reactor. The total exhaust NOx level was approximately 12–15 ppmv and was produced almost entirely in the preburner ahead of the reactor. A small quantity of steam injected into the preburner reduced the NOx emissions to 5–6 ppmv. Development of the combustion system has continued with the objectives of reducing CO and UHC emissions, understanding the parameters affecting reactor stability and spatial non-uniformities which were observed at low inlet temperature, and improving the structural integrity of the reactor system to a level required for commercial operation of gas turbines. Design modifications were completed and combustion hardware was fabricated for additional full-scale tests of the catalytic combustion system in March 1995 and January 1996. This paper presents a discussion of the combustor design, the catalytic reactor design and the results of full-scale testing of the improved combustor at MS9OOIE cycle conditions in the March 1995 and January 1996 tests. Major improvements in performance were achieved with CO and UHC emissions of 10 ppmv and 0 ppmv at base load conditions. This ongoing program will lead to two additional full-scale combustion system tests in 1996. The results of these tests will be available for discussion at the June 1996 Conference in Birmingham.
Systematic Optimisation of a Turbofan Bypass Duct System (2012)

A reduction of CO2 emissions of aero engines can only be achieved by a reduction in the fuel consumption. For turbofan engines a major key for this is an increase in the engine bypass ratio to enhance the propulsive efficiency. This leads to an increased mass flow in the bypass duct and hence higher contributions of the bypass duct system to the flow pressure losses and hence the engine fuel consumption. Additionally the turbofan core engine gets smaller in size and the overall diameter of the engine increases. This requires advanced engine mounting concepts, such as core mounted subsystems, which influence the arrangement and the mechanical and aerodynamic design of components in the bypass duct such as fan outlet guide vane, struts, fairings or bifurcations. This requires an optimized design of the turbofan bypass system with regards to structural, aerodynamic and acoustic criteria. The topology of the bypass duct as well as the position and the design of the individual components have a significant impact on the weight, the efficiency and the noise radiation of the engine and hence need to be investigated in a systematic approach. Such a design approach was developed in the R&T project OPAL, led by Rolls-Royce Deutschland and funded by the German Federal State of Brandenburg. The design approach covers the following steps: - Optimization of the bypass duct shape with regards to minimum pressure loss taking into consideration the mechanical requirements of an engine with core mounted subsystems. - Optimization of strut, fairing and bifurcation shapes with regards to minimum pressure loss, robustness against flow deviations and minimized upstream flow effects taking into consideration structural and mechanical requirements by engine loads and subsystem routings. - Optimization of fan outlet guide vane profile and plan form shape with regards to minimum pressure losses and maximum working range taking into consideration structural and acoustic constraints. - Optimization of fan-outlet guide vane, strut and bifurcation interaction with regards to minimum pressure losses and maximized aerodynamic stability of the fan and outlet guide vanes. The current paper will present the design approach, the optimization processes and the results of the optimization of the turbofan bypass duct system for the application on modern high-bypass ratio aero engines.
A mobile self-leveling landing platform for VTOL UAVs (2015)

A semi-autonomous mobile self-leveling landing platform designed to launch, recover and re-launch VTOL UAVs without the need for human intervention is described. The landing platform is rugged, lightweight and inexpensive, making it ideal for civilian applications that require a base station from which a rotorcraft UAV can be launched and/or recovered on terrain that is normally unsuitable for UAV take-off and landing. This landing platform is capable of autonomously self-leveling on rough terrain and inclines up to 25°, and can operate in isolated remote locations for extended periods of time using large onboard lithium batteries and wireless communication. The unique design aspects of this landing platform are that it is mobile, self-leveling, and man-portable. A fully-operational prototype has been designed, constructed and evaluated. Design details and experimental results are presented to demonstrate the landing platform's functionality, and that all primary design requirements have been met.
Petri Net-Based Efficient Determination of Optimal Schedules for Transport-Dominant Single-Arm Multi-Cluster Tools (2017)

It is a great challenge to find an optimal one-wafer cyclic schedule for a single-arm multicluster tool that is widely adopted in semiconductor fabrication. Aiming to tackle this significant problem, an optimal scheduling strategy is determined first for each individual tool under the condition that the bottleneck individual tool is transport-bound. Then, by developing a Petri net model with robot waiting being explicitly described to reveal the properties of the entire system, this paper shows that to schedule such a tool optimally is to allocate the robot waiting time properly. Then, this paper presents the necessary and sufficient conditions for the existence of an optimal one-wafer cyclic schedule. Thereafter, an efficient algorithm is developed to check the given conditions and find such a schedule efficiently if existing. Finally, two industrial examples are used to verify that the proposed method is applicable and effective.
A Computational Physical Organic Study of a Torque, Lock, and Propagate Approach and Validation with the Synthesis of Configurationally Stable First‐Generation Helically Twisted Acenes (2022)

Abstract Hybrid polyaromatic hydrocarbons (PAHs) consisting of helicene and acene domains, referred to as [7]heli‐D‐acenes, are introduced as scaffolds to generate enantiopure twisted acenes (heli‐twistacenes) by a torque, lock, and propagate (TLP) approach. Computational methods with and without dispersion corrections were used to explore the structural and electronic features of these PAHs and to explore the possible formation of twistomers that might complicate reaction mixtures. Syntheses of unsubstituted and disubstituted members of the [7]heli‐D‐acene series confirmed the viability of the TLP approach, and together with the computational results, provided proof‐of‐concept of this new approach as a viable means to generate enantiopure twisted‐acenes. The X‐ray structures, absorption, fluorescence, phosphorescence, and CD spectra of these first generation heli‐acenes are compared to the structure and photophysical properties of pentacene and [7]helicene. A high barrier for the enantio‐enriched M enantiomer of 19,24‐dicyano[7]heli‐D‐anthracene verified its configurational stability at room temperature.
<title>A Novel Proximity X-Ray Image Intensifier Tube</title> (1977)

A novel proximity-type x-ray image intensifier tube is described. This device has the main advantage of fewer sources of unsharpness so that this advantage can be traded for higher MTF performance or dose reduction performance. In addition, the size and shape of this device are not restricted as in the case of current minifying-type x-ray image intensifier tubes. Various systems applications employing this device, such as in simple direct-view intensified panel-like fluoroscopy, low dose TV fluoroscopy and direct radio-graphic miniaturization, are discussed.
X-ray Crystallographic Structures of Trimers and Higher-Order Oligomeric Assemblies of a Peptide Derived from Aβ<sub>17–36</sub> (2014)

A peptide derived from Aβ17-36 crystallizes to form trimers that further associate to form higher-order oligomers. The trimers consist of three highly twisted β-hairpins in a triangular arrangement. Two trimers associate face-to-face in the crystal lattice to form a hexamer; four trimers in a tetrahedral arrangement about a central cavity form a dodecamer. These structures provide a working model for the structures of oligomers associated with neurodegeneration in Alzheimer's disease.
Advanced analytics on SAP HANA: Churn risk scoring using call network analysis (2015)

We present a demonstration based on SAP HANA to show a novel approach to churn risk scoring. Our focus is customer retention within a telecommunications setting. The purpose of this demonstration is to help identify customers who should be targeted for a customer retention marketing campaign. The data analysis considers multiple factors - churn likelihood (based on incoming and outgoing communications), customer influence (based on social connections) and the average revenue per customer. The results are presented using skyline visualization and advanced UI techniques to easily and intuitively interpret the analysis.
Novel Design of Collaborative Automation Platform Using Real-Time Data Distribution Service Middleware for an Optimum Process Control Environment (2016)

Refining and petrochemical processing facilities utilize various process control applications to raise productivity and enhance plant operation. Client–server communication model is used for integrating these highly interacting applications across multiple network layers utilized in distributed control systems. This paper presents an optimum process control environment by merging sequential and regulatory control, advanced regulatory control, multivariable control, unit-based process control, and plant-wide advanced process control into a single collaborative automation platform to ensure optimum operation of processing equipment for achieving maximum yield of all manufacturing facilities. The main control module is replaced by a standard real-time server. The input/output racks are physically and logically decoupled from the controller by converting them into distributed autonomous process interface systems. Real-time data distribution service middleware is used for providing seamless cross-vendor interoperable communication among all process control applications and distributed autonomous process interface systems. Detailed performance analysis was conducted to evaluate the average communication latency and aggregate messaging capacity among process control applications and distributed autonomous process interface systems. The overall performance results confirm the viability of the new proposal as the basis for designing an optimal collaborative automation platform to handle all process control applications. It also does not impose any inherent limit on the aggregate data messaging capacity, making it suitable for scalable automation platforms.
Optical and sensory properties of ZnO nanofibrous layers grown by magnetron sputtering (2012)

This paper presents optical and sensory properties of ZnO nanofirous layers grown by a cost-effective and fast fabrication method based on magnetron sputtering. The as-prepared nanofibrous layers show good conductive properties which are of interest for gas sensing structures. Their application for hydrogen detection is demonstrated in premiere, and the developed H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> sensor structure exhibits good response / recovery behavior under ultraviolet (UV) light, and good sensitivity. This method is cost-effective and facile and has a great potential for various sensorial applications.
Synthesis of 5-Nitrotetrazolate via the Aqueous Oxidation of 5-Aminotetrazole (2022)

The preparation of the important energetic precursor sodium nitrotetrazolate has long been plagued by safety and purity problems. The prevailing synthesis methods utilizing the Sandmeyer reaction proceed via sensitive, explosive intermediates and would be classified as a high-hazard process. In this work, we directly oxidize precursor 5-aminotetrazole to 5-nitrotetrazole in aqueous solution utilizing a heterogeneous titanium superoxide catalyst, skipping the sensitive intermediates inherent in the current industrial Sandmeyer route and providing a vastly safer process with a yield of 50–65%. The prepared sodium nitrotetrazole is of high purity and therefore is directly useful in the synthesis of the primary explosive DBX-1, which is a synthesis that is highly sensitive to impurities. The improved safety and excellent product purity demonstrates the superiority of our route.