bluuebunny/crossref_metadata_2025_split huggingface dataset:
Co-occurrence of genes encoding carbapenemase, ESBL, pAmpC and non-β-Lactam resistance among Klebsiella pneumonia and E. coli clinical isolates in Tunisia
Authors: Ben Sallem R. , Laribi B. , Arfaoui A. , Ben Khelifa Melki S. , Ouzari H. I. , Ben Slama K. , Naas T. , Klibi N. 
Published: January 2022

Abstract
This study aimed to investigate the molecular mechanisms of carbapenem and colistin resistance in K. pneumoniae and E. coli isolates obtained from hospitalized patients in Carthagene International Hospital of Tunis. A total of 25 K. pneumoniae and 2 E. coli clinical isolates with reduced susceptibility to carbapenems were recovered. Susceptibility testing and phenotypic screening tests were carried out. ESBL, AmpC, carbapenemase and other antibiotic resistance genes were sought by PCR-sequencing. The presence of plasmid-mediated colistin resistance genes (mcr-1-8) was examined by PCR and the nucleotide sequence of the mgrB gene was determined. The analysis of plasmid content was performed by PCR-Based Replicon Typing (PBRT). The clonality of isolates was assessed by PFGE and multilocus sequence typing (MLST). All of the isolates produced carbapenemase activity. They showed a great variation in the distribution of ESBL, AmpC, carbapenemase and other plasmid-mediated resistance determinants. K. pneumoniae isolates carried blaNDM-1 (n = 11), blaOXA-48 (n = 11), blaNDM-1 + blaOXA-48 (n = 1), blaNDM-1 + blaVIM-1 (n = 1), blaOXA-204 (n = 1), along with blaCTX-M, blaOXA, blaTEM, blaCMY, blaDHA and blaSHV genes variants on conjugative plasmid of IncL/M, IncR, IncFIIK, IncFIB, and IncHI1 types. Three sequence types ST101, ST307 and ST15 were identified. The mgrB alteration g109a (G37S) was detected in a single colistin-resistant, NDM-1 and OXA-48-coproducing K. pneumoniae isolate. The two E. coli isolates belonged to ST95, co-produced NDM-1 and CTX-M-15, and harboured plasmid of IncFII and IncFIB types. To our knowledge, this is the first report in Tunisia of NDM-1, OXA-48, and CTX-M-15 coexistence in colistin-resistant K. pneumoniae ST15.
The electron‐bifurcating FeFe‐hydrogenase Hnd is involved in ethanol metabolism in Desulfovibrio fructosovorans grown on pyruvate
Authors: Payne Natalie , Kpebe Arlette , Guendon Chloé , Baffert Carole , Ros Julien , Lebrun Régine , Denis Yann , Shintu Laetitia , Brugna Myriam 
Published: January 2022

Abstract
Desulfovibrio fructosovorans, a sulfate‐reducing bacterium, possesses six gene clusters encoding six hydrogenases catalyzing the reversible oxidation of H2 into protons and electrons. Among them, Hnd is an electron‐bifurcating hydrogenase, coupling the exergonic reduction of NAD+ to the endergonic reduction of a ferredoxin with electrons derived from H2. It was previously hypothesized that its biological function involves the production of NADPH necessary for biosynthetic purposes. However, it was subsequently demonstrated that Hnd is instead a NAD+‐reducing enzyme, thus its specific function has yet to be established. To understand the physiological role of Hnd in D. fructosovorans, we compared the hnd deletion mutant with the wild‐type strain grown on pyruvate. Growth, metabolite production and consumption, and gene expression were compared under three different growth conditions. Our results indicate that hnd is strongly regulated at the transcriptional level and that its deletion has a drastic effect on the expression of genes for two enzymes, an aldehyde ferredoxin oxidoreductase and an alcohol dehydrogenase. We demonstrated here that Hnd is involved in ethanol metabolism when bacteria grow fermentatively and proposed that Hnd might oxidize part of the H2 produced during fermentation generating both NADH and reduced ferredoxin for ethanol production via its electron bifurcation mechanism.
Mapping immature fruit colour‐related genes via bulked segregant analysis combined with whole‐genome re‐sequencing in pepper (Capsicum annuum)
Authors: Song Zhao , Zhong Jian , Dong Jichi , Hu Fang , Zhang Baige , Cheng Jiaowen , Hu Kailin 
Published: January 2022

AbstractFruit colour is one of the most intuitive economic traits attracting consumers' attention for horticultural crops. Many genes associated with mature fruit colour have been identified in pepper, but genes influencing immature fruit colour are mainly unknown. In the present study, pepper inbred lines with light‐yellow (CSJ009) and green (CSJ010) immature fruit colour were used as female and male parents, respectively, to generate an F2 segregation population. Genetic analysis indicated that the light‐yellow immature fruit colour in CSJ009 is controlled by a single recessive gene, tentatively named as ly. The single‐nucleotide polymorphism (SNP)‐index analysis and genetic linkage analysis delimited the ly locus into a 6.51 Mbp region on chromosome 9, and four candidate genes Capana09g000680, Capana09g000671, Capana09g000715 and Capana09g000692 were identified in the linkage region. Nonsense mutation of APRR2 may be responsible for the low carotenoid content in immature CSJ009 fruits. These results lay a foundation for future immature fruit colour improvement via molecular genetics approaches and further identification of new immature fruit colour‐related genes in pepper.
Equivalent Performance Parameters for Turboblowers and Compressors
Authors: Davis Hunt 
Published: January 2022

Abstract
The author defines the parameters of equivalent performance for turbocompressors and shows how they may be used for correlation of shop and field testing with design information. Three classifications of correlation are defined with different degrees of correlation accuracy. The first class includes cases where the correlation error is negligibly small, even when the test fluid is different from the design fluid. The second class includes cases where the correlation accuracy is reasonably good. The third class offers no satisfactory correlation conditions. It is proposed that similar concepts of correlation be recognized by and incorporated into the appropriate Power Test Code for turbocompressors.
On the Basic Mechanics of the Grinding Process
Authors: Backer W. R. , Merchant M. E. 
Published: January 2022

Abstract
New geometrical concepts of grinding are presented and combined with metal-cutting principles to predict grinding forces. Experimental evidence is used to show the dependence of grinding mechanics on three fundamental variables, the length and cross-sectional area of the undeformed chip, and the cutting speed. These same three variables are shown to have no effect on grinding ratio, the wheel wear varying only with the metal removed for the test conditions employed. Variations in grinding ratio from run to run are found to have a distribution in line with tool-life tests for other machining operations.
An Analog Study of a High-Speed Recording Servomechanism
Authors: Schwartzenberg J. W. 
Published: January 2022

Abstract
This paper presents an analysis of a high-speed recording servomechanism. Because of the nonlinearities present, the system is simulated on an analog computer. Minimum balancing times with a 100 per cent step-input signal are obtained for various combinations of system parameters. Several types of damping are considered, and the a-c carrier action of the amplifier is included in the simulation. The frequency response and following error of the system are also considered.
Experimental Measurement of Metal-Cutting Temperature Distributions
Authors: Reichenbach G. S. 
Published: January 2022

Abstract
Two new methods of measuring cutting temperatures have been evaluated. The first is a radiation technique using a lead-sulfide cell. The cell is arranged to sight through a small hole drilled in the work material sensing radiation from the shear plane and clearance face of the tool. Peak temperatures in these regions have been obtained but shear-plane temperature distributions could not be determined successfully. The second technique uses a 0.005-in. single wire imbedded in the side of a workpiece as a thermocouple. With orthogonal cutting the tool passed beneath the wire so that the wire passed up the tool face still imbedded in the chip. By this method it was possible to determine the temperature field throughout the chip and work. These temperature fields have been compared to theoretical predictions and show only fair agreement. The lack of agreement is due partially to the simplifying assumptions of orthogonal cutting and a true geometric shear plane necessary for theoretical solution. The necessity of locating the thermocouple junction on the side of the work introduced errors from side flow of the chip and certain other edge effects. The iteration procedure of Trigger and Chao has been extended to tools of any rake angle and simplified by use of a conducting-paper electrical analog.
Influence of Load and Thermal Distortion on the Design of Large Thrust Bearings
Authors: Baudry R. A. , Kuhn E. C. , Wise W. W. 
Published: January 2022

Abstract
High-capacity vertical waterwheel generators require large thrust bearings in which the load is carried on a thin hydrodynamic film of oil. Thermal and load distortion of the bearing parts have to be limited to a low value to permit the normal and complete formation of the oil film predicted by the hydrodynamic theory of lubrication. Excessive load and thermal distortion materially affect bearing performance and may result in bearing failure. This paper describes some design considerations given to vertical waterwheel-generator thrust bearings in order to avoid highly concentrated loading during the starting period, and to obtain minimum distortion of the pad during operation at normal speed and load.
Comparison of Semi-Empirical Solutions for Crack Propagation With Experiments
Authors: Frisch J. 
Published: January 2022

Abstract
The crack-propagation characteristics of two aluminum alloys and several steels have been investigated in sheet materials under uniaxial tension. Empirical formulas based on ultimate strength and initial crack length were found to be a sufficiently effective method for establishing the relative merit of a material in its resistance to crack propagation. Comparison of experimental data with criteria obtained from the energy-release rate or stress-concentration theory shows that neither method yields reliable material constants.
Formulations for the Thermodynamic Properties of Steam and Water
Authors: Schnackel H. C. 
Published: January 2022

Abstract
The thermodynamic properties of steam and water as presented in the well-known Keenan and Keyes’ Steam Tables are expressed as formulas and condensed tables. This is done to facilitate the calculation of steam and water properties on high speed digital computers. Methods of iteration and interpolation using these formulas and tables are discussed. Errors incurred in using the formulations as well as the ranges involved are also described.
Prediction of Flashing Water Flow Through Fine Annular Clearances
Authors: Agostinelli A. , Salemann V. 
Published: January 2022

Abstract
The flow of a flashing mixture of water and steam through smooth annuli of fine clearance has been investigated experimentally. Test data have been obtained with inlet conditions to 600 F and 3000 psi. Critical conditions have been observed experimentally up to these temperatures and pressures. With the assumption that the flashing mixture is homogeneous a method for the prediction of flow and two-phase pressure drop is presented and discussed.
Boiling Heat Transfer to Water Containing a Volatile Additive
Authors: Leppert G. , Costello C. P. , Hoglund B. M. 
Published: January 2022

Abstract
Aspects of local boiling in forced circulation when the boiling fluid contains small percentages of alcohol are discussed. Particular emphasis is placed on the improvement in smoothness of boiling and in the decrease of average bubble size when the additive is present, as contrasted with boiling distilled water. Experimental results, including photographs, are presented for surface boiling from the outside of a cylindrical stainless-steel tube placed normal to the flow. Data are also presented for the subcooled boiling of distilled water, and comparisons are made with correlations from the literature.
Static and Dynamic Characteristics of Compensated Gas Bearings
Authors: Richardson Herbert H. 
Published: January 2022

Abstract
A static and dynamic analysis of a general configuration of a compensated gas bearing is presented for the case in which the effects of shaft rotation on performance are negligible. The equations developed can be used quantitatively and are particularly useful in assessing the effects on static and dynamic performance of changes in design parameters such as fluid properties, compensation schemes, and geometry. To illustrate the use of the equations developed, a comparison is made between two common types of hydrostatic gas bearings—the pool bearing and the inherently compensated bearing—and a design example for a specific bearing requirement is worked.
The Effect of Wakes on the Transient Pressure and Velocity Distributions in Turbomachines
Authors: Meyer R. X. 
Published: January 2022

Abstract
In general, the blades of a multistage turbomachine move through a row of wakes shed from the blades of the preceding stage. This interaction between blade rows results in a transient fluctuation of the pressure distributions, which in turn can be expected to have an important effect on the drag, the maximum lift coefficient and, in the case of hydraulic machines, on the cavitation characteristics of the affected blades. In the paper, the time-dependent pressure gradient and the velocity are determined for the case of two-dimensional incompressible flow through lightly loaded cascades.
Optimization of Plate-Type Air Preheaters for Automotive Gas Turbines
Authors: Hryniszak W. 
Published: January 2022

Abstract
This paper deals with recuperative plate-type heat-exchanger elements for a composite air preheater for automotive gas turbines. The general requirements and optimization of the essential dimensions of such an element are discussed.
Such optimization leads to the smallest possible weight for a given temperature and pressure efficiency. As these two efficiencies affect the specific fuel consumption of the gas turbine, two further optimizations lead to: (a) The best pressure ratio of the turbomachines for given initial temperatures; and (b) the best temperature and pressure efficiency of the air preheater. The weight of this heat exchanger affects the performance of the vehicle propelled by the gas-turbine unit in different ways. Further optimization therefore leads to the best weight of the air preheater at a given average speed.
Cost considerations which affect the design of the element are influenced by the method of manufacture and the choice of materials as well as the method of maintaining clean channels in the heat-exchanger elements.
Optimal Synthesis of Linear Sampling Control Systems Using Generalized Performance Indexes
Authors: Kalman R. E. , Koepcke R. W. 
Published: January 2022

Abstract
This paper is concerned with the design of linear control systems so as to minimize some quadratic performance index. The method of design is applicable to both sampling and continuous control systems. Using the concepts of “state” and “transition matrix,” the design problem can be solved, via the technique of dynamic programming, by means of simple iterative computations. In this way, the classical Wiener method of design is extended in several different directions: (a) Using generalized performance indexes, (b) optimizing for classes of input signals rather than single inputs, (c) assuring stability of the optimally designed system.
Gyro-Integrating Mass Flowmeter
Authors: Akeley L. T. , Batchelder L. A. , Cleveland D. S. 
Published: January 2022

Abstract
This paper describes an integrating mass flowmeter designed for high-pressure natural-gas metering. The meter described provides direct reading of pounds of gas on a cyclometer register as well as electrical contacts for remote telemetering mass flow. No electronic elements are used in the design. A three-axis gyroscope is used for integrating. The meter is designed for 1 per cent integrating accuracy over 30 to 100 per cent of rated flow. It operates over a 20 to 1 flow range.
Optimization of Cathode Structure for Anode-Supported Planar Solid Oxide Fuel Cell
Authors: Fan Shengliang , Wang Guoli , Yang Lei , Liu Pengwei , Han Xu , Jin Zunlong 
Published: January 2022

Abstract
It is always an important research direction to improve the performance of solid oxide fuel cells (SOFCs) through structural optimization. For anode-supported SOFC, the thin cathode thickness results in an uneven distribution of oxygen concentration in the porous electrode, which limits the output performance. In this paper, a three-dimensional model of the anode-supported planar SOFC was established, and the thickness of the cathode diffusion layer in the area covered by the connector was increased to improve the uniformity of oxygen distribution in the cathode. The results show that increasing the thickness of the cathode diffusion layer under the connector can significantly improve the overall output performance of SOFC. The uniformity of oxygen concentration distribution in the cathode is improved, the local current density under the connector is increased, and the maximum output power density of the cell is increased by 29.14%. The results show that the output performance of the SOFC and the uniformity of gas distribution in the porous electrode can be improved by increasing the thickness of the cathode diffusion layer under the connector in the structure design and practical application of the SOFC. The research of this paper provides a reference for the optimization design of SOFC.
Large Eddy Simulation of the Layout Effects on Wind Farm Performance Coupling With Wind Turbine Control Strategies
Authors: Wu Chunlei , Wang Qiang , Yuan Renyu , Luo Kun , Fan Jianren 
Published: January 2022

Abstract
Large eddy simulation (LES) coupling with wind turbine control strategies is newly developed to quantitatively study the layout effects on wind farm performance. The turbine rotor is parameterized with an actuator line method (ALM), and the five-region generator-torque control and the proportional-integral (PI) pitch control are newly introduced to regulate the operation of the wind turbine. First, a dynamic inflow boundary condition is designed to validate the current simulation framework. The validation results show that the simulated power curve agrees well with the real power curve of the wind turbine, and the maximum power error of the simulation only accounts for 5% of the rated power. Then, to study the layout effects, four kinds of wind farm arrangements are designed by varying the alignment method and the turbine spacing. The results show that the staggered arrangement and increasing the stream-wise spacing are beneficial to reduce the velocity deficit. The power comparison results show that the staggered arrangement has obvious advantages among the four cases, and it increases the capacity factor (CF) by 25% and improves the wind farm efficiency by about 50% compared with the aligned arrangement. The present simulation framework can be used to optimize the turbine layout for the potential wind farms.
Influence of Cutting Conditions on Dimensional Integrity
Authors: Narayan Sumesh , Kumar Abhishek Kaushal , Ali Aruf , Mamun Kabir 
Published: January 2022

Abstract
This study investigates the effect of machining parameters correlating to the quality and precision of machined parts. The main focus is given to coordinate measuring machine (CMM) features, dimensional accuracy and surface roughness. Samples of three hardness materials were milled according to a standard design while varying machining parameters. The varied parameters were the type of milling machine used, feed rate and spindle speed. A CMM of 0.0001mm precision was used to measure the dimensions of the machined parts and analysis of variance (ANOVA) was used as the analysis to study the impact of each machining parameter on the quality and accuracy of the machined specimen. The study revealed that spindle speed of the milling machine, hardness of the material and the machine automation type is the factor that has a significant effect on the surface roughness of the machined features and hardness, spindle speed and a combination of hardness plus spindle speed had a significant effect on the dimensional accuracy of the machined features. The significant difference in data collection using the three CMM touch probes available was also studied, which revealed that the effect of changing probe diameter does not have any significant effect on a standard design feature when collecting data.
Application of Topology Optimization to Design a Structural Panel Subjected to Blast Loading
Authors: Schiffer Gillian , McMullen Kevin , Bruhl Jakob 
Published: January 2022

Abstract
The purpose of this study is to apply topology optimization to the design of a protective underbody panel for armored combat vehicles subjected to improvised explosive devices (IEDs). The increased use of IEDs by terrorist organizations over the last two decades has led to the death of thousands of soldiers and imposed critical damage to vehicles. There is interest in developing a protective panel that minimizes deflection and mass. The goal of this study is to design a lightweight, modular, and affordable panel, which provides increased protection to the vehicle occupants. Topology optimization may be used to create unique structures through a subtractive formulation. As additive manufacturing capabilities improve, topology optimization enables the design of efficient structures that are difficult to manufacture using traditional methods. Eight topology optimization studies were conducted and produced unique structural designs that were compared to established designs. The deflection, strain energy, and stress of optimized models from were compared to a hollow structural section (HSS) of equivalent mass and height. Results indicated the performance of optimized models were dependent on the topology optimization design goal. The methodology presented may be used in the future for projects which aim to minimize mass and maximize stiffness.
Fluid Flow in Between the Differentially Rotating Spherical Shells in the Presence of Toroidal Magnetic Field
Authors: Sharma Bharti , Srivastava Neetu 
Published: January 2022

Abstract
The behavior of fluid flow in differentially rotating shells with radii a and b where a &lt; b, is discussed in the magnetic field’s presence. Out of the two significant elements of the magnetic field which are toroidal and poloidal, the toroidal magnetic field plays the dominant role for determining the behavior of fluid flow in the case of the rotating bodies. The solution for modelled equations is observed by perturbation method. Also the solution for flow quantities are observed by variable separable method for specific value of constant used in the abovementioned method.
Critical Shear Stress for Erosion Under Laminar Jet Flow
Authors: Pease Leonard F. , Bamberger Judith Ann , Minette Michael J. 
Published: January 2022

Abstract
Here we evaluate critical shear stresses for erosion under laminar jet flow. To date critical shear stresses for erosion, as embodied in Shields diagrams, have largely been developed for turbulent flow both experimentally and mathematically. However, curves on the Shields diagrams diverge among various models at lower particle Reynolds numbers. Indeed, how critical shear stresses for erosion develop under fully laminar jet flow conditions (not simply laminar boundary layers under turbulent flow) remains unclear. Here we address this gap, which is particularly important for mobilization of the smallest particles. We find the Shields parameter to be inversely proportional to the particle Reynolds numbers under laminar jet flow conditions similar to turbulent conditions.