bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incidence and risk factors for COVID‐19 associated candidemia (CAC) in ICU patients
Authors: Kayaaslan Bircan , Kaya Kalem Ayşe , Asilturk Dilek , Kaplan Betul , Dönertas Gülen , Hasanoglu Imran , Eser Fatma , Korkmazer Ruveyda , Oktay Zeynep , Ozkocak Turan Isıl , Erdem Deniz , Bektas Hesna , Guner Rahmet 
Published: February 2022

AbstractBackgroundCritically ill COVID‐19 patients have a high risk for the development of candidemia due to being exposed to both well‐defined classical risk factors and COVID‐19‐specific risk factors in ICU.ObjectivesIn this study, we investigated the incidence of candidemia in critically COVID‐19 patients, and the independent risk factors for candidemia.Patients/methodsCOVID‐19 patients hospitalised in ICU during 1‐year period (August 2020 to August 2021) were included. Clinical and laboratory characteristics of all COVID‐19 patients, applied treatments, and invasive procedures that may predispose to candidemia were recorded.ResultsOf 1229 COVID‐19 patients, 63 developed candidemia. Candidemia incidence rate was 4.4 episodes per 1000 ICU days. The most common species was Candida albicans (52.3%). Only 37 patients (58.7%) received antifungal therapy. The presence of central venous catheter (OR 4.7, 95% CI 1.8–12.2, p < .005), multifocal candida colonisation (OR 2.7, 95% CI 1.4–5.2, p < .005), a prolonged ICU stay (≥14 days) (OR 1.9, 95% CI 1.08–3–37, p < .05), the absence of chronic lung disease (OR 0.4, 95% CI 0.1–0.9, p < .05) and the absence of corticosteroid use (OR 0.3, 95% CI 0.14–0.52, p < .0001) were significantly associated with candidemia.ConclusionsOur study filled the knowledge gap in the literature about the impact of COVID‐19‐associated risk factors for the development of candidemia. The classical risk factors for candidemia had a significant effect on candidemia, and contrary to expectations, corticosteroids had a protective effect against the development of candidemia. The results of these studies showing interesting effects of corticosteroids in critically ill COVID‐19 patients should be confirmed by further studies.
Working principle and relevant physical properties of the Swiss Liquid Jet Aesthesiometer for Corneal Sensitivity (SLACS) evaluation
Authors: Nosch Daniela S , Oscity Matthias , Steigmeier Peter , Käser Emanuele , Loepfe Markus , Joos Roland E 
Published: February 2022

AbstractPurposeTo describe and evaluate relevant physical properties of the Swiss Liquid Jet Aesthesiometer for Corneal Sensitivity (SLACS) for ocular surface sensitivity measurement.MethodsCharacteristics of Liquid Jet (LJ) droplets (consisting of isotonic saline solution) were analysed: vertical and horizontal displacement and speed of LJ droplets were recorded with the aid of the High Speed Photron FASTCAM NOVA S6 camera (stimulus duration: 40 ms). Stimulus mass was assessed for 20 sets of 10 LJs with aid of a microbalance (pressure range of 100–1500 mbar).ResultsBecause continuous flow LJ disintegrated into droplets in the lower pressure range (<700 mbar), pulsed stimuli were applied in order to obtain similar stimulus characteristics across the applied pressure range. For all measurements, very little variability was observed. Vertical and horizontal displacement did not exceed 0.13 mm in either direction. The mass per shot showed an unexpected cubic dependency on pressure. Up to approximately 700 mbar, LJ speed showed an almost linear relationship. For the pressure range of >700–1500 mbar, variability increased and speed decreased compared to the expected in a linear manner. However, this may be caused by the difficulty of identifying pattern changes of LJ droplets from one high speed image frame to the next with increasing stimulus speed, when determining LJ speed via pixel count.ConclusionsSwiss Liquid Jet Aesthesiometer for Corneal Sensitivity was shown to deliver fine droplets with a pulsed stimulus mode, in a repeatable manner with precise localisation to the ocular surface. Very little variability was observed in LJ speed and mass for the typical pressure range required for clinical sensitivity measurements.
Management of chronic low back pain and the impact on patients’ personal and professional lives: Results from an international patient survey
Authors: Fullen Brona , Morlion Bart , Linton Steven J. , Roomes David , van Griensven Joop , Abraham Lucy , Beck Craig , Wilhelm Stefan , Constantinescu Cristina , Perrot Serge 
Published: February 2022

AbstractObjectiveThe objective of this study was to investigate the impact of chronic low back pain (CLBP) on patients’ personal and professional lives, and management strategies applied to treat CLBP.MethodsA 60‐question survey was developed, and respondents from 16 countries with a self‐reported physician's diagnosis of CLBP were recruited via an online market research survey panel. Respondents were stratified as having mild, moderate, or severe pain. Target sample sizes per country and for pain severity were set. Data were weighted according to the known population and prevalence of CLBP in each country and the number of respondents from that country.ResultsResults from 9642 CLBP patients indicated that almost a quarter of patients with severe CLBP report a psychological comorbidity. Prescription pain medications were more commonly used by patients with severe CLBP (56%) than those with mild (20%) or moderate (34%) CLBP. Among those with severe CLBP who had been prescribed pain medication, 58% were prescribed opioids, with 1 in 4 patients using opioids for more than 5 years. Patients were primarily managed by general practitioners/primary care physicians, physiotherapists, neurologists, or orthopedic surgeons. CLBP negatively impacted patients’ daily activities, social lives, and work productivity.ConclusionChronic low back pain has pronounced effects on patients’ personal relationships, ability to work, and daily living. Almost 1 in four patients with severe CLBP reported a psychological comorbidity. Adherence to guidelines appears inconsistent, which is noteworthy as a substantial subgroup of patients with severe CLBP had been prescribed opioid medication for more than 5 years. Improved education is required to support healthcare professionals (HCPs) in identifying and understanding the complex biopsychosocial needs of CLBP patients to optimize pain management and to encourage referral of CLBP patients to physiotherapists and psychologists.
Interregional inequality in Africa, convergence, and multiple equilibria: Evidence from nighttime light data
Authors: Kacou Kacou Yves Thierry 
Published: February 2022

AbstractUnderstanding the dynamics of interregional inequality in Africa is important when formulating development policies. In this paper, we investigate the convergence pattern of regional inequality within 49 African countries over the period 1992–2012 using satellite night‐light‐based inequality proxies. We find evidence of multiple equilibria in regional income inequality. Countries belonging to clubs with high regional inequality level do not show any tendency to converge toward the clubs with low regional inequality, indicating that these countries are indeed stuck in regional income inequality traps. The idea of regional income inequality traps is also confirmed by a distributional dynamic analysis that uncovered evidence of regional income inequality persistence with a limited degree of mobility between convergence clubs. From the convergence analysis, we found that the initial conditions in the economic development, natural resource rent, urbanization, political institutions, development aid programs, and infrastructure are very important determinants of regional income inequality. Our findings provide policy makers some direction for future economic policies.
Safeguard Features of a Fast-Breeder-Reactor Power Plant
Authors: McCarthy W. J. , McMath F. C. 
Published: February 2022

Abstract
In the design of a reactor power plant, special attention to safety is required in order to safeguard the investment in the plant and to insure that danger to the public is reduced to negligible proportions. Some design features relevant to the safety of a fast-breeder-reactor power plant are described. The decision to enclose the radioactive portions of the plant in a gastight building to provide a final barrier between the reactor and the public is discussed. Criteria developed for locating the reactor on a safe and economically suitable site are presented.
Fluid Flow Through Two Orifices in Series: III—The Parameters of Metastable and Stable Flow of Hot Water
Authors: Kinderman W. J. , Wales E. W. 
Published: February 2022

Abstract
The flow of hot water, with saturation pressure above the downstream pressure, through orifices or nozzles depends largely upon the nature of the expansion of the fluid and the confinement of the expansion by the orifice or nozzle. Intermolecular forces as influenced by surface tension tend to metastabilize the initial liquid phase to a corresponding subsaturated pressure. These forces also tend to metastabilize the droplets formed in steam at the critical size corresponding to the critical pressure at expansion. The influence of orifice or nozzle form on the expansion process for initially stable and metastable entering fluid is analyzed with confirming test data interpreted from the intermediate-pressure measurements between two identical orifices in series. Control effects obtainable with change of the intermediate pressure between two orifices as determined by the thermal state of the fluid are briefly discussed and a new practical application form of such a control element as applied to condensate removal from steam systems is described. Attention is directed toward new avenues for further investigation in this field.
Use of Nonlinear Valve Characteristics in the Control of a Simple Blending Process
Authors: Shearer J. L. 
Published: February 2022

Abstract
A simple, continuous, energy-blending process is analyzed to attain an understanding of its dynamic performance when the flow rate of either the hot or cold fluid is time variant. A linearized analysis based on small changes of all variables is employed to estimate the static and dynamic performance of the process when simple controllers are used to regulate temperature of the out-flowing mixture. Possible advantages are indicated for the use of nonlinear flow versus stroke characteristics of the flow-control valve together with its connecting lines. Graphical analyses show the performance of various control schemes when the system variables undergo large changes and indicate how valve characteristics may be chosen for the blending process under control.
A Practical Application of Uncertainty Calculations to Measured Data
Authors: Thrasher L. W. , Binder R. C. 
Published: February 2022

Abstract
In order to answer questions as to the reliability of measurements, it is desirable to classify two types of measurements: (a) The multiple sample, and (b) the single sample. The case for multiple-sample measurement is well established, whereas the case for single sample has not been established. It is proposed that the tester estimate his error—the uncertainty interval—and give odds that the error would be less than the uncertainty interval if the measurement were repeated a large number of times. A numerical example is presented.
Integration of Steam and Hydro Power in Northern California
Authors: Dreyer Walter 
Published: February 2022

Abstract
The paper reviews the history of installations and integration of steam and hydro power in northern California. The functions of steam-generated power are outlined and the economics of mingled hydro and steam demonstrated for several assumed conditions. The importance of making effective all of the installed or dependable capacity without duplicating installations is emphasized and illustrated by a graphic example. The paper concludes with a brief discussion of reserve capacity in a mingled power system and with some thoughts about the role of future nuclear plants.
Nonlinear Analog Study of a High-Pressure Pneumatic Servomechanism
Authors: Shearer J. L. 
Published: February 2022

Abstract
A detailed analog simulation was made in order to evaluate the effects of nonlinear valve characteristics, nonlinear ram-chamber compliance, and coulomb friction in the ram on the dynamic performance of a high-pressure pneumatic servomechanism that had been studied previously with a linearized analysis. This analog study revealed that a major part of the discrepancy between measured frequency-response characteristics and the frequency-response characteristics computed from a linearized analysis is caused by coulomb friction in the ram. Although the system is decidedly unsymmetrical when the ram moves near one end of its cylinder, the over-all dynamic characteristics are nearly the same as when the ram moves near its center position. Thus, a simple linearized analysis of ram-chamber characteristics, which is possible only when the ram is near its center position, is applicable throughout most of the operating range of the ram. The nonlinear characteristics of the control valve did not seem to be significant in the problem because large pressure differences across the ram never were required to drive the mass load.
Hunting Due to Lost Motion
Authors: Poritsky H. 
Published: February 2022

Abstract
Hunting of a servosystem, due to lost motion, say, in one of its mechanical links, but in absence of input signals, is considered. If the slack is assumed to be taken up suddenly, the motion is governed by a linear differential equation but with proper discontinuities when the direction of motion in the loose link is reversed. For the case of second-order systems it is shown that, if the characteristic roots are complex, a periodic hunting motion always exists, and that the system, no matter how it is started, will converge to this hunting motion. If the characteristic roots of the second-order system are real, then a periodic hunting motion exists, but depending upon how the system is started, it may converge to this motion or it may converge to a stable position at either end of the lost-motion band. Third and higher-order systems are studied in a similar way and the equations for determination of periodic hunting motion obtained. Second-order systems, in which the system “coasts” as the slack is taken up, are discussed briefly.
Natural-Convection Heat Transfer From a Horizontal Cylinder Rotating in Air
Authors: Dropkin David , Carmi Arieh 
Published: February 2022

Abstract
This paper presents the results of experimental investigation of convection heat transfer from horizontal rotating cylinders to ambient air. Two hollow copper cylinders were used, one 4.5 in. and another 3.25 in. outside diameter. These cylinders were nickel plated to minimize the heat transfer by radiation and were internally heated by electric cartridge heaters. The surface temperatures were determined by thermocouples peened to the inside surface. The experimental procedure was to investigate systematically each dimensionless parameter which was previously determined by dimensional analysis. The results indicate that, up to a certain value of Reynolds number, rotation has no effect on the heat-transfer coefficient. Above this critical value the heat-transfer coefficient increases as the speed of rotation increases. In the region where the data overlap, the experimental results reported in this paper are in close agreement with those of other investigators. The flow pattern around the cylinder was also investigated. Titanium tetrachloride smoke was used for this study.
Solving the Melting Problem Using the Electric Analogy to Heat Conduction
Authors: Otis D. R. 
Published: February 2022

Abstract
The one-dimensional, heat-conduction equation with melting at one boundary is transformed to a form suitable for simulation on an analog computer. The transformed equation is identical with the heat-conduction equation with internal heat generation and a nonmelting boundary. This allows simulation of the melting process continuously with time rather than stepwise, and the number of “cells” in the heat-conduction-circuit analog remains constant throughout the solution.
A Graphical Method for the Analysis of Piecewise Linear Control Systems, With Particular Application to Relay Controls
Authors: MacMillan R. H. 
Published: February 2022

Abstract
A graphical method is described for the analysis of piecewise linear control systems. By means of it both transient and steady oscillations can be studied. After the “characteristic curves” of a system have been computed and plotted, it is shown that the effects of dead zone, solid friction, backlash, and various lead devices are easily taken into account, without further computation. The method is illustrated by a more detailed examination of the behavior of relay controls, and a few of the charts obtained by the method are given.
Forces and Power Required to Turn Aluminum and Seven Alloys
Authors: Boston O. W. , Gilbert W. W. 
Published: February 2022

Abstract
Turning tests on pure aluminum 1100-H14 and seven aluminum alloys were made to develop the formula for the tangential cutting force as a function of the material constant, the feed in inches per revolution, and the depth of cut in inches, when cutting dry, with a solid high-speed steel tool ground for turning aluminum. Equations for each metal have been developed and it is shown that the constants and exponents vary for each metal. Unit net power at the cutter has been computed for several sizes of cut for each metal and the values for a light cut and a medium-size cut have been plotted against each of the mechanical properties of the materials. These data show that knowing the Brinell hardness, the ultimate or yield strength of the metal or the shear strength, values of the unit net horsepower at the cutter can be computed with considerable accuracy.
Effect of Cold Work on Elevated-Temperature Properties of Types 301, 305, and 310 Stainless Steels
Authors: Lula R. A. , Lena A. J. , Johnson H. M. 
Published: February 2022

Abstract
The elevated-temperature strength of AISI Types 301, 305, and 310 stainless steels can be improved by cold-working, provided extensive recrystallization during exposure does not take place. The rupture strength of cold-rolled materials decreases progressively with increasing recrystallization and eventually becomes poorer than that of annealed material when the amount of recrystallization exceeds 50 to 60 per cent. It is suggested that microstructural changes which occur as a result of recrystallization account for the detrimental effect that recrystallization exerts on high-temperature strength. These include a change in grain size and redistribution of chromium carbides in Types 301, 305, and 310, and the accelerated formation of sigma in Type 310.
The Application of a New Structural Index to Compare Titanium Alloys With Other Materials in Airframe Structures
Authors: Jackson L. R. , Gordon S. A. 
Published: February 2022

Abstract
The evaluation of structural materials for airframes is based on the strength/density ratio or, more precisely, the ultimate strength/density ratio, the compressive yield strength/density ratio, and the structural indexes for plates and columns. The structural indexes developed for plate elements have, in the past, been based on the formulaSe=1K1/2[12(1−μ2)π2]1/2Fbu3/2Er1/2
The application of this relationship to complex sections depends on the weighted average of the various plate elements that constitute the section and on the proper selection of their end fixities. Past experience indicates that this method is often unreliable and does not predict the failing load of the section, since the formula predicts only the stress at which the first buckle occurs in each respective element. A new method of predicting the failing load of a section in compression was suggested in 1954 by R. A. Needham. His method has been used to develop a new structural index for the evaluation of the strength/density ratio of materials in compression. In this report, this new structural indexSe=2.56Fcc2.18(ηFcyE)0.59 is compared with the results of compression tests on aluminum sections at room temperature, and similar tests on titanium-alloy angles and channels at room and elevated temperatures. The aluminum test data are from Needham’s report; the titanium-alloy test data were supplied by Convair (San Diego) and Boeing (Seattle). Excellent agreement is obtained in all cases. It is believed that the new structural index will provide a reliable method of evaluating the elevated-temperature performance of materials such as titanium, in comparison with other materials, when only the compressive stress-strain curves are available at each temperature.
Thermostructural Efficiencies of Compression Elements and Materials
Authors: Gerard George 
Published: February 2022

Abstract
Minimum-weight equations for failure of solid and wide columns, plates and plate assemblies (crippling), and optimum stringer panels are presented in terms of suitable structural loading and material-efficiency parameters. From these equations the comparative structural efficiency of plates and stringer panels was investigated. Similarly, the comparative efficiency of various materials was studied for elevated-temperature, stringer-panel applications. By analytically determining the optimum spacing of ribs or webs in stringer panel-rib or multiweb construction, respectively, a composite structure of minimum weight is obtained. For such structures the structural-loading and material-efficiency parameters are generally different from those obtained for the individual elements. Typical results are presented for composite structures and some general considerations are presented for selection of materials for thermal-flight aircraft.
Aircraft Structural Testing Techniques at Elevated Temperatures
Authors: Brouns R. C. , Baird R. B. 
Published: February 2022

Abstract
The object of this paper is to review some of the test-system requirements and problems associated with structural testing of aircraft at elevated temperatures. A brief description of loading methods used for the past generation of aircraft is presented. The requirements of an elevated-temperature test facility are established on the basis of the need for simultaneous heating and loading of an aircraft structure. Heating devices such as heating blankets, strip heaters, film heaters, induction coils, radiant heating coils, and infrared lamps which are being investigated by the Wright Air Development Center are discussed in relation to methods of attaching loads. Complications caused by simultaneous heating and loading are illustrated by a discussion of two structural tests performed at the Wright Air Development Center. A description is also given of an electronic computer developed to program the aerodynamic heating of a structure.
Some NACA Research on Effect of Transient Heating on Aircraft Structures
Authors: Duberg J. E. 
Published: February 2022

Abstract
A brief presentation is made of some of the radiant-heating apparatus developed by the National Advisory Committee for Aeronautics (NACA) to simulate aerodynamic heating of aircraft structures. Some results of the effects of thermal stresses on the stiffness and deflection of aircraft structures are demonstrated by tests incorporating the radiant-heating apparatus.
Oronite High Temperature Hydraulic Fluids 8200 and 8515
Authors: Furby N. W. , Peeler R. L. , Stirton R. I. 
Published: February 2022

Abstract
Aircraft hydraulic fluids and hydraulic fluid systems have entered a new era. The advent of guided missiles and the fantastic increase in speed and operating altitude of aircraft make present requirements for fluids and systems far more severe than was imagined 15 years ago. This paper presents data on two outstanding fluids developed for use over a wide temperature range. These fluids, Oronite High Temperature Hydraulic Fluids 8200 and 8515, have pushed top operating temperatures upward some 300 deg F without reducing performance at low temperatures.