bluuebunny/crossref_metadata_2025 huggingface dataset:
Perinatal support for couples during COVID‐19: A descriptive qualitative study
Authors: Shorey Shefaly , Tan Thiam Chye , Thilagamangai  , Mathews Jancy , Lim Siew Hoon , Shi Luming , Chua Jing Shi , Chan Yiong Huak , Law Evelyn , Chee Cornelia , Chong Yap Seng
Published: July 2022

Aims and objectives

To explore the perspectives of parents during the perinatal period amid the COVID‐19 pandemic and explore the experiences of Singaporean parents receiving perinatal support via the Supportive Parenting App (SPA).

Background

The stressors accompanying parenting responsibilities often affect the overall well‐being of the family unit. With the emergence of the COVID‐19 pandemic, Singaporean parents are forced to shoulder childcare responsibilities with minimal support due to safety restrictions. The Supportive Parenting Application (SPA) was introduced to parents during the start of the pandemic to offer timely additional support. It is a mobile health application‐based educational support for parents across the perinatal period, consisting of features such as peer support, expert advice and discussion forums.

Design

Descriptive qualitative study.

Methods

Semi‐structured one‐to‐one interviews were conducted with 33 parents (16 from the control group, 17 from the intervention group) in an ongoing randomised controlled trial between June 2021 and February 2022. The COREQ checklist was used to guide the reporting of the data.

Results

Four themes with 10 subthemes describing the perinatal experiences of parents were identified. The themes include ‘Ups and downs’ of parenting experiences; Perinatal care from ‘best care’ to ‘flying blind’; What kept couples going and Use of technology—a way forward.

Conclusion

Although COVID‐19 negatively affected parents' availability of care and support, most could still access other support sources to help them. Additionally, the SPA was found to be a dependable information source for the intervention group parents. Future research could work on improving technology‐based support based on the feedback given to offer better quality perinatal care for parents.

Relevance to clinical practice

Technology‐based support provided by healthcare professionals helps provide reliable perinatal information and support for parents. More efforts should be directed towards developing quality informational resources and support to improve perinatal care.

Patient or public contribution

Patients/members of the public contributed to the data collected and were involved in member checking to ensure the rigour of the study.

Clinical Trial Registration Number: NHG DSRB: 2019/00875.
Improved detection of multiple sclerosis lesions with T2‐prepared double inversion recovery at 3T
Authors: Costagli Mauro , Lapucci Caterina , Zacà Domenico , Bruschi Nicolò , Schiavi Simona , Castellan Lucio , Stemmer Alto , Roccatagliata Luca , Inglese Matilde
Published: July 2022

Background and Purpose

Double inversion recovery (DIR) imaging is used in multiple sclerosis (MS) clinical protocols to improve the detection of cortical and juxtacortical gray matter lesions by nulling confounding signals originating from the cerebrospinal fluid and white matter. Achieving a high isotropic spatial resolution, to depict the neocortex and its typically small lesions, is challenged by the reduced signal‐to‐noise ratio (SNR) determined by multiple tissue signal nulling. Here, we evaluate both conventional and optimized DIR implementations to improve tissue contrast (TC), SNR, and MS lesion conspicuity.

Methods

DIR images were obtained from MS patients and healthy controls using both conventional and prototype implementations featuring a T2‐preparation module (T2P), to improve SNR and TC, as well as an image reconstruction routine with iterative denoising (ID). We obtained quantitative measures of SNR and TC, and evaluated the visibility of MS cortical, cervical cord, and optic nerve lesions in the different DIR images.

Results

DIR implementations adopting T2P and ID enabled improving the SNR and TC of conventional DIR. In MS patients, 34% of cortical, optic nerve, and cervical cord lesions were visible only in DIR images acquired with T2P, and not in conventional DIR images. In the studied cases, image reconstruction with ID did not improve lesion conspicuity.

Conclusions

DIR with T2P should be preferred to conventional DIR imaging in protocols studying MS patients, as it improves SNR and TC and determines an improvement in cortical, optic nerve, and cervical cord lesion conspicuity.
The effects of ultraviolet, gamma- and X-ray irradiation on the growth, antibacterial activity and radio-protective of Lactobacillus rhamnosus
Authors: Bazukyan I.L. , Rostomyan A.V. , Hovhannisyan A.G. , Aleksanyan T.M. , Hakobyan L.L. , Dallakyan A.M. , Haertlé T.
Published: July 2022

Ionizing radiation is widely applied in food production as preservation technology and for correction of the gut microbiome of cancer patients, rescuers, astronauts etc. Lactic acid bacteria (LAB) can be used for the same reason. The main goal of this study was to investigate the effect of irradiation on some activities of Lactobacillus rhamnosus MDC 9661 and its effect on the survival of irradiated rats. The results indicate that both ultraviolet (during 45 min) and X-ray irradiations (with 2 Sv) decreased the CFU and the antibacterial activity of the strain. Higher than 700 Sv dose of X-ray irradiation resulted in the total inhibition of antibacterial activity with the total reduction of colony forming units less than 10 cells ml−1, while irradiated with 1000 Sv dose L. rhamnosus MDC 9661 did not lose its proteolytic activity. It was also shown that L. rhamnosus MDC 9661 was not immunogenic in the organism of the rats and cannot lead to the development of autoimmune responses. L. rhamnosus MDC 9661 demonstrated the necessary properties for probiotics and can be effectively used for the correction of the gut microbiome of all target groups. The co-aggregation of the cells is one of the mechanisms for resistance of LAB to irradiation.
Cap‐binding complex assists RNA polymerase II transcription in plant salt stress response
Authors: Zhang Huairen , Li Xiaoyi , Song Ruitian , Zhan Zhenping , Zhao Fengyue , Li Zicong , Jiang Danhua
Published: July 2022

Adaptive response to stress involves an extensive reprogramming of gene expression. Under stressful conditions, the induction of efficient changes in messenger RNA (mRNA) production is crucial for maximized plant survival. Transcription and pre‐mRNA processing are two closely related steps in mRNA biogenesis, yet how they are controlled in plant stress response remains elusive. Here, we show that the Arabidopsis nuclear cap‐binding complex (CBC) component CBP20 directly interacts with ELF7, a subunit of the transcription elongation factor RNA Pol II‐associated factor 1 complex (PAF1c) to promote RNA Pol II transcription in plant response to salt stress. CBP20 and ELF7 coregulate the expression of a large number of genes including those crucial for salt tolerance. Both CBP20 and ELF7 are required for enhanced RNA Pol II elongation at salt‐activated genes. Though CBP20 also regulates intron splicing, this function is largely independent of ELF7. Our study reveals the function of an RNA processing regulator CBC in assisting efficient RNA Pol II transcription and pinpoints the complex roles of CBC on mRNA production in plant salt stress resistance.
Electrophysiological correlates of the effect of set size on object switching in working memory
Authors: Ding Gangqiang , Ye Weidong , Cao Bihua , Li Fuhong
Published: July 2022

Previous studies have revealed the effect of set size (the number of activated items) on object switching in working memory, but the underlying neural mechanism remains unclear. In this study, participants were asked to first remember two (small size) or three (large size) two‐digit numbers and the corresponding geometrical figures as different references for numerical comparison and then compare a series of numbers (10–99) to the reference numbers cued by different geometrical figures. The cue repeated or switched across trials. Behavioral results revealed that the switch cost was greater in the large‐size condition than in the small‐size condition. Event‐related potential results showed that in the N2 component, an interaction was observed between set size and transition, with a significant transition effect (switch minus repeat) in the large‐size condition and a non‐significant transition effect in the small‐size condition. The same interaction was observed in the P3 component, with a larger amplitude difference (switch minus repeat) in the large‐size condition than in the small‐size condition. These results suggested that when set size is increased, the effort to inhibit the irrelevant items increases, resulting in large cost of object switching in working memory.
SPIRITUAL INTELLIGENCE: PARTICIPATING WITH HEART, MIND, AND BODY
Authors: Wiseman Harris , Watts Fraser
Published: July 2022

This introductory article to the thematic section on “Spiritual Intelligence” sets out the ways in which spiritual intelligence is currently conceptualized. Most prominently, spiritual intelligence is understood as an adaptive intelligence which enables people to develop their values, vision, and capacity for meaning. Questions arise as to whether spiritual intelligence is a distinct form of intelligence, and how to frame it if it is. It is questionable whether psychometric approaches justify concluding there is a distinct spiritual intelligence, and the authors reject any notion of a God spot in the brain specifically dedicated to spiritual intelligence, which is a much more broadly embodied phenomenon. The authors suggest that spiritual intelligence most likely makes use of existing cognitive architecture, though applied in a distinctive way. This article finishes with a brief introduction to the four main articles in this thematic section, which present spiritual intelligence as a kind of participation in transcendent being. The four articles approach the cognitive, embodied, meditative, and ritual aspects of spiritual intelligence as participation.
MEANING AND EMBODIMENT IN RITUAL PRACTICE
Authors: Wiseman Harris
Published: July 2022

The article explores the interaction of verbal and nonverbal semantic levels in the performance of Christian ritual. The article maps the distinction between theoretical and performative knowledge onto Barnard and Teasdale's Interacting Cognitive Systems model to give a (partial) account of how meaning emerges in ritual participation. With Christian ritual, both know‐how and know‐that are needed. Above all, it is their interaction that generate the richness of meaning in ritual performance. Three core claims are made. First, many contemporary concepts of ritual have at least one flaw in that they do not grasp the relationality between verbal and nonverbal, wherein both dimensions have a semantic integrity of their own. Second, there is an ideological valuation of the semantic levels. The experiential level is not only meaningful in its own right, but the fundamental ground of spiritual knowing. Third, combining learning styles and kinds of attention can be valuable for eliciting the full semantic richness of ritual participation.
KNOWING SLOWLY: UNFOLDING THE DEPTHS OF MEANING
Authors: Wiseman Harris
Published: July 2022

The article explores an aspect of spiritual intelligence characterized as a lifelong search for meaning. Slow knowing involves wrestling with perplexity. Periods of such tarrying gradually facilitate an unfolding of meaning. More than just the content of one's knowledge, it is the relationship, the how or manner of one's relationship with meaning that grounds the spiritual generativity of the seeking. Slow knowing is presented as an existential orientation, a lifelong process akin to ongoing conversion. Part 1 distinguishes such slow knowing from other senses of slow in current discourse (Kahneman's fast/slow thinking framework, and meditative concepts of slow mind). Part 2 explores slow knowing through the lenses of lectio divina and the use of metaphor in religious language. Slow knowing is characterized as having both individual and social dimensions. The article concludes with the concern that the conditions needed for slow knowing—and thus for spiritual intelligence—are undermined by the hasty pace of contemporary life.
NATURAL SELECTION AT NEW COLLEGE: THE EVOLUTION OF SCIENCE AND THEOLOGY AT A SCOTTISH PRESBYTERIAN SEMINARY
Authors: Harris Mark
Published: July 2022

The contemporary creation–evolution debate has become so polarized (over the issue of either Genesis or evolutionary science) as to obscure the more nuanced questions that have arisen in the historical and theological reception of Darwinism. Edinburgh's New College has been the academic home to some prominent scientists and theologians who have grappled with these questions since the early days of evolutionary science in the first half of the nineteenth century. Most obviously, this activity was focused on the decision to create a Chair in Natural Science in 1845, which would be occupied by a recognized scientist. The Chair became “extinct” in the 1930s, but in between times, its holders made important theological assessments of evolution along the way. This article outlines the contributions made by the individuals who occupied this Chair, as well as more recent figures in the evolution of science and theology at New College.
Educational Potential of 3D Multi-User Virtual Environments
Authors: Marešová Hana , Ecler Daniel
Published: July 2022

The text focuses on the issue of 3D multi-user virtual environments and their use in education. In the wake of the global Covid-19 pandemic, there was a worldwide need for a rapid transition in education at all levels of schooling and in lifelong learning to the online space. As this was a rapid organisational change, schools and lifelong learning institutions often found themselves in situations where tools not previously tested in the school were used, or online tools were used that did not lead to the desired effect. Therefore, it is necessary to investigate which types of online tools are most appropriate for education, depending on the age of the learners and the learning topic. This text analyses the educational potential of 3D multi-user virtual environments, which hold significant benefits for the application of basic didactic principles that bring significant advantages in terms of learning outcomes, in particular the principle of illustration, learning from simulated virtual experiences as well as direct contact with the learning community. The text concludes by discussing current perspectives on the effectiveness of these environments in the educational process.
Kompetence ve vzdělávání a strategie profesního rozvoje
Authors: Kříž Jaroslav
Published: July 2022

VETEŠKA, Jaroslav, TURECKIOVÁ, Michaela, 2020. Kompetence ve vzdělávání a strategie profesního rozvoje. Praha: Česká andragogická společnost. 178 s. ISBN 978-80-907809-1-0
The Effect of Dispersions on Creep Properties of Aluminum-Copper Alloys
Authors: Giedt W. H. , Sherby O. D. , Dorn J. E.
Published: July 2022

The creep properties of a system of 3 to 5 per cent Cu in A1 alloys containing hard particles of CuAl2 were investigated throughout a temperature range of 350 to 578 K. The results supplemented with additional tensile-test data show that these properties are primarily dependent on the volumetric mean free path of the CuAl2 particles and independent of minor variations in composition andheat-treatment. The creep stress was found to correlate with the creep rate-temperature parameter Z = ϵ˙seΔH/RT. Above ln Z = ln (ϵ˙seΔH/RT) = 46.0 and below ln Z = 27.5 the finer dispersions are superior, whereas over the intervening range of Z-values the coarser dispersions are superior. The energy for activation ΔH, was found to be a constant of about 37,000 cal per mol.
On the Drilling of Metals: 1—Basic Mechanics of the Process
Authors: Oxford C. J.
Published: July 2022

The cutting action of a twist drill is very complex. This paper describes an investigation of this complex phenomenon through use of a quick-stop technique to freeze the action. The formation of chips, both along the cutting edges and under the chisel edge, is considered. Chip-flow angles, measured experimentally, are related to effective rake angle along the cutting edges, using a new derivation of the normal rake angle for a twist drill. The effects of point angle, drill design, and workpiece material are considered. The split (crankshaft) point for heavy web drills is investigated and its operation described.
In-Plane Bending Properties of Welding Elbows
Authors: Vissat P. L. , Del Buono A. J.
Published: July 2022

This paper presents results of strain-gage investigations conducted on relatively heavy-wall “Weld-ELLS” having a ratio of bend radius to nominal pipe size of 1½:1. Also, several Weld-ELLS having a ratio of bend radius to nominal pipe size of 1:1 were tested. A comparison is made of the results against theory. Design factors for Weld-ELLS are established and tabulated.
Viscoelasticity of Polymethyl Methacrylate—an Experimental and Analytical Study
Authors: Knowles J. K. , Dietz A. G. H.
Published: July 2022

This paper is concerned (a) with a presentation of static tensile stress-strain data under many different experimental conditions on several types of methyl methacrylate, together with an empirical equation to describe them, and (b) with an attempt to correlate the static behavioral characteristics of two varieties of methacrylate by means of an extension of the Boltzmann-Volterra theory of the elastic aftereffect to an extent that facilitates the prediction of creep and constant-strain-rate curves from stress-relaxation data to within an error acceptable for engineering purposes.
Pulsating-Flow Measurement—A Literature Survey
Authors: Oppenheim A. K. , Chilton E. G.
Published: July 2022

Technical publications on the measurement of pulsating flow are reviewed. Fundamental aspects of the subject are stressed, and applications of pressure-differential meters are emphasized because of their importance to industry. Problems related to these meters are classified into those concerned with flow through the meter test section, the effect of the flow system on the meter, and the transmission of the signal from meter to recorder. Operation and application to pulsating flow of other meters such as the turbine type and electromagnetic flowmeter, the hot-wire anemometer, and the so-called “true mass-rate flowmeter” also are outlined. A summary of information available in codes and manuals is included.
Applying Bearing Theory to the Analysis and Design of Pad-Type Bearings
Authors: Raimondi A. A. , Boyd John
Published: July 2022

A review-type paper which presents charts and tables for the design and analysis of both fixed-pad and pivoted-pad thrust bearings. These data yield theoretical bearing-performance characteristics on the basis of what is generally regarded to be the most usable theory. Typical bearing design examples are included which illustrate the facility with which theoretical calculations can be made.
Experimental Boiler Studies of the Breakdown of Amines
Authors: Jacklin C.
Published: July 2022

A report of the results obtained when several types of amines were tested for breakdown to ammonia in an experimental boiler. Test pressures ranged from 250 to 2500 psi and temperatures from 400 to 1200 F. Test results indicate that morpholine, which has been used successfully at 1600 psi and 1000 F, also shows relatively good stability at 2500 psi and 1200 F.
The Thermal Barrier—Structures
Authors: Hoff N. J.
Published: July 2022

In the past few years the term “barrier” has become popular in aeronautics. Not so long ago we heard of the sonic barrier which in the minds of many laymen represented a solid wall of compressed air which would not let an airplane through at the speed of sound. More recently the expression “thermal barrier” has been coined to indicate that the heating effect of air will set a definite limit to the speed of aircraft that can never be surpassed. As far as the sonic barrier is concerned, events have shown that supersonic flight is well possible. As a matter of fact, bullets flew at supersonic speeds even during the last century, and if no law of nature prevented them from doing so, it was unreasonable to expect airplanes to be stopped by the sonic barrier. The author is convinced that in a similar manner the difficulties presented by the high temperatures accompanying flight at supersonic speeds will be overcome through research and development. Thus the thermal barrier is not a stone wall that will shatter all hopes of high supersonic flight.
High-Frequency Oscillations of a Flame Held by a Bluff Body
Authors: Kaskan W. E. , Noreen A. E.
Published: July 2022

Experimental data are presented on the occurrence of flame-sustained transverse oscillations in a 2 × 4-in. duct with a V-gutter flameholder. The flame-speed versus flow-velocity field of burner operation was divided into an oscillation region and a nonoscillation region. The boundary line between the two was approximately described by an equation of the formSuU1.6=const where Su is the laminar flame speed and U is the flow velocity. The oscillation was characterized by the formation of vortexes downstream of the flameholder tips. These vortices distorted the flame front in such a way as to provide the driving force for the oscillation.
The Influence of Tap-Drill Size and Length of Engagement Upon the Strength of Tapped Holes
Authors: Oxford C. J. , Cook J. A.
Published: July 2022

The influence of tap-drill size (minor diameter) upon the strength of threaded assemblies has been the subject of much speculation, analysis, and testing, but the results presented generally have been inconclusive or have not covered all of the many possible types of thread failure. This paper reports the results of a series of correlative tests and supporting analysis performed in an attempt to solve this problem. Failures can be of three types: Breakage of the external-thread member; stripping of the external thread; or stripping of the internal thread. The effect of drilled-hole oversize is examined and is found to be a significant variable in some cases. Formulas are developed which extend the experimental data to permit analysis of most practical thread-element combinations. For assemblies of usual proportions and materials, it is found that 60 per cent thread height is adequate.
A Theory of Fatigue-Damage Accumulation in Steel
Authors: Henry D. L.
Published: July 2022

At present, there is no theoretical method for predicting the change in the endurance limit of steel specimens subjected to various numbers of cycles of overstressing at different stress levels. The theoretical and most of the experimental work accomplished thus far has been concerned with studying the change in endurance life at some stress level resulting from the accumulation of various amounts of overstressing at other stress levels. It is the purpose of this paper to present a simple theoretical model for predicting the change in endurance limit resulting from the accumulation of overstressing cycles at moderate levels of overstress and for moderate degrees of fatigue damage. Review of the literature indicates that it is reasonable to assume that fatigue damage occurring prior to the formation of a visible crack is equivalent to an increase in a “stress-concentration factor” associated with the particular defect in the specimen which will form the fatigue nucleus. The application of simple notch-factor concepts and the use of an empirical formula for the S-N curve for steel resulted in an equation for predicting the change in the S-N curve when specimens are subjected to overstressing histories producing moderate amounts of fatigue damage.
Steam-Piping Design to Minimize Creep Concentrations
Authors: Robinson Ernest L.
Published: July 2022

Believing that steam-piping design for high-temperature service has heretofore been based largely upon elastic analysis of expansion stresses without adequate consideration of the importance of high-temperature creep, the author discusses the principles governing the relaxation of expansion stresses during service at high temperature and points out the possibility of creep concentrations in local spots of maximum stress. A number of specific examples are given to show that ordinary piping design usually can be made without such concentrations. Contrariwise, the type of expansion flexibility which invites excessive creep is illustrated. The desirability of cold springing pipe so as to minimize stress at high temperature is emphasized.
An Approximate Solution of Compressible Turbulent Boundary-Layer Development and Convective Heat Transfer in Convergent-Divergent Nozzles
Authors: Bartz D. R.
Published: July 2022

A method has been derived for computing the development of the velocity boundary layer, the temperature boundary layer, and the local convective heat transfer in convergent-divergent nozzles. The method is based on approximate solutions of the integral momentum and integral energy equations for compressible turbulent boundary layers. To obtain the solutions, a flow model is adopted for which are prescribed the velocity and temperature profiles in the boundary layer, the skin-friction law, and the relation between heat and momentum transfer. The local heat-transfer coefficient is expressed as an explicit function of the boundary-layer thicknesses. The effects of nozzle size and throat radius of curvature on boundary-layer development and heat transfer are determined for certain similar nozzle contours in common use. The results of the solution are demonstrated by a sample calculation for a conventional rocket nozzle operating under typical conditions. The computed local heat fluxes were found to be in approximate agreement with those measured during rocket-motor tests using a nozzle of the same contour.
An Interferometric Study of Free-Convection Heat Transfer from Enclosed Isothermal Surfaces
Authors: Jones C. D. , Masson D. J.
Published: July 2022

Variations of point and average heat-transfer coefficients with spacing are presented for (a) horizontal isothermal cylinders near plane partial enclosures and (b) vertical isothermal prisms of small height in a duct.
Shear-Plane Temperature Distribution in Orthogonal Cutting
Authors: Weiner J. H.
Published: July 2022

An analytical solution is presented for the temperature distribution along the shear plane in orthogonal cutting. The principal assumption made is that the heat transferred by conduction in the direction of motion of the workpiece or chip may be neglected. The nature of the error involved in this assumption is investigated. The over-all fraction of shear-plane heat transferred into the workpiece is also computed and compared with previous results.
Transient Thermal Stresses in Circular Disks and Cylinders
Authors: Horvay G.
Published: July 2022

The effect of a suddenly applied peripheral temperature ϑ(R,φ,z,t)=Tcosnφ 1(t) upon circular disks and cylinders is considered. The most interesting results are (a) for thermal shock (t = very small) the stresses in an unrestrained cylinder are φφ︵∼zz︵∼-EαT1-μ(r/R)R/πκtcosnφ and all other stresses vanish; (b) in the steady state (t = ∞) the temperature distribution is ϑ(r,φ)=T(r/R)ncosnφ and all stresses vanish.
Dynamic Properties of Nodular Cast Iron: Part 2—Size Effect
Authors: Majors Harry
Published: July 2022

Rotating-beam endurance tests at room temperature have been conducted on 0.86-in-diam minimum notch sections and 1.25-in-diam minimum unnotched sections in order to compare fatigue data obtained from geometrically similar specimens having minimum diameters of 0.19 in. and 0.30 in., respectively. Comparisons have been made for tension-test data obtained from sections of 0.19 in., 0.50 in., and 0.75 in. diam. A series of exploratory tests in fatigue were made on grooved specimens and for two notch angles for comparison with results obtained on ungrooved specimens. Results are reported for the optimum chemical composition without any nickel content in the annealed and as-cast condition.
A Summary of NACA Research on Heat Transfer and Friction for Air Flowing Through Tube With Large Temperature Difference
Authors: Pinkel Benjamin
Published: July 2022

The results of experimental and analytical studies performed at the NACA to determine the heat-transfer and friction coefficients for the flow of air through tubes with large difference in temperature between tube wall and air, (a) for smooth tubes of circular cross section; (b) for tubes of noncircular cross-sectional shapes; and (c) for tubes with various degrees of surface roughness, are summarized. The experiments for the smooth tubes of circular cross section cover a range of tube-wall temperature from 535 R to 3050 R, inlet-air temperature from 535 R to 1500 R, Reynolds numbers from 1000 to 500,000, exit Mach numbers up to 1, and tube length-to-diameter ratios from 15 to 120. Methods of correlating these data are discussed. The tubes of noncircular cross-sectional shape, namely, (a) square, (b) rectangular, and (c) triangular, were investigated at tube wall-to-air temperature differences up to 1200 F and Reynolds numbers between 2500 and 250,000. Three degrees of surface roughness, obtained by machining square threads into the inner surface of the tube, were investigated for temperature differences between the air and tube wall up to 1500 F and Reynolds numbers from 1000 to 350,000.
Application of Quality-Control Requirements in Manufacture of Components for a Coaxial-Carrier System
Authors: Chapman A. T.
Published: July 2022

Economic solution of transmission problems in a new coaxial-carrier system required limitation of excursions of sensitive characteristics from the design center. Basic quality-control techniques were utilized in developing a pattern of distribution requirements for the key characteristics of the critical electronic components. A description of the statistical techniques is presented with several illustrative factory applications.
Experimental Superheater for Steam at 2000 Psi and 1250 F—Progress Report After 12,000 Hours of Operation
Authors: Eberle F. , Ely F. G. , Dillon J. A.
Published: July 2022

In order to supplement laboratory studies on certain new alloys developed in the past few years, a test element was constructed and installed in an operating boiler at the Twin Branch plant. Operation, which is similar to a small superheater, was started in March 1950. Experience with the unit for the first two years was described in a previous paper. The present paper gives the record for the past two-year period and includes preliminary information derived from metallurgical examination of specimens removed from the element after nearly 7000 hr of operation.
Design and Operation of High-Recovery Regenerative-Type Air Preheaters: Part 1—Special Features of the Regenerative-Type Air Preheaters
Authors: Braddon George
Published: July 2022

Air preheating has become the most widely accepted method of recovering heat from flue gases of high-efficiency steam-generating units. The drive to reduce stack losses further and improve over-all efficiencies continues. The regenerative air preheater possesses unique characteristics which contribute to its ability to achieve maximum reduction in stack losses while permitting continuous operation over long periods. This paper deals with those features of the regenerative air preheater which are inherent in the type and are created expressly for the purpose of realizing high efficiency coexistent with high availability.
A Study of the Effects of Cyclic Thermal Stresses on a Ductile Metal
Authors: Coffin L. F.
Published: July 2022

The results of a study of cyclic strain and fatigue failure arising from cyclic thermal stresses are reported. By means of a test apparatus described in a companion paper, a cyclic temperature is imposed on a thin tubular test specimen subjected to complete longitudinal constraint. Hence, the cyclic strain is the independent variable. The following studies are reported: (a) Effect of thermal-stress cycling on strain hardening and life-to-failure for a fixed mean temperature, (b) effect of degree and kind of previous cold work on strain hardening and cycles-to-failure, (c) effect of mean temperature on thermal-stress cycling, (d) effect of period of cycle on cycles-to-failure, and (e) effect of prior strain cycling on stress-strain characteristics. The significance of factors such as hysteresis, Bauschinger effect, strain hardening, strain aging, and fatigue-crack formation is discussed, and a mechanism is described to relate these factors. Evidence is presented to show that strain hardening is not an important factor in the problem. The concept of total plastic strain is discussed.
Theoretical Calculation of the Equation of State and Transport Properties of Gases and Liquids
Authors: Bird R. B. , Hirschfelder J. O. , Curtiss C. F.
Published: July 2022

Several years ago a summary article was written (1) about the theoretical calculation of the viscosity and several other properties of gases and gas mixtures. Since that time further calculations of the equation of state and transport coefficients of dense gases and liquids have been made. Although the statistical mechanical theory is an involved and highly mathematical topic, and although some of the numerical computations are quite complex, the final results, nevertheless, may be presented in terms of tabulated functions, which are easy to use in practical calculations. The formulas and tables given in this paper should prove useful in engineering-design calculations and in chemical-process studies. Furthermore, the underlying statistical mechanical theory whenever possible should be used to give intelligent interpretation to the analysis and correlation of chemical and engineering data on the properties of matter.
Generalized pvT Properties of Gases
Authors: Nelson L. C. , Obert E. F.
Published: July 2022

In this paper two sets of generalized compressibility charts are presented: One set is based upon critical temperatures and pressures as in the past; the other set is based upon pseudo-reduced co-ordinates obtainable from the Lennard-Jones force potential. In both sets the underlying data are more extensive than those used in constructing older charts since a complete survey of existing pvT data was made. The results of this survey for 30 gases are contained in a Bibliography of 275 items which has been constructed to show the extent of the experimental data by including the ranges of pressure and temperature for each item. Although the charts are intended for engineering computations, the chart for the low-pressure region (pr = 0 to 1), for example, has a deviation of 1 per cent for 26 gases.
Dynamic Characteristics of Silicone Rubber
Authors: Painter G. W.
Published: July 2022

The unusual high and low-temperature properties of silicone rubber have made it a desirable material for vibration isolators designed for service at temperature extremes. In general, silicone cannot be substituted directly for such elastomers as natural rubber and neoprene in established designs. This lack of interchangeability results principally from the lower tensile strength and the unusual load-deflection characteristics of the material. A program to investigate the dynamic properties of silicone rubber was undertaken to provide the design engineer with information which would allow the material to be utilized properly. This paper deals with the viscoelastic properties of silicone rubber under various conditions of strain, frequency, and temperature. Where possible, comparisons are made with natural rubber.
Pitch discrimination is better for synthetic timbre than natural musical instrument timbres despite familiarity
Authors: Holmes Emma , Kinghorn Elizabeth E. , McGarry Lucy M. , Busari Elizabeth , Griffiths Timothy D. , Johnsrude Ingrid S.
Published: July 2022

Pitch discrimination is better for complex tones than pure tones, but how pitch discrimination differs between natural and artificial sounds is not fully understood. This study compared pitch discrimination thresholds for flat-spectrum harmonic complex tones with those for natural sounds played by musical instruments of three different timbres (violin, trumpet, and flute). To investigate whether natural familiarity with sounds of particular timbres affects pitch discrimination thresholds, this study recruited non-musicians and musicians who were trained on one of the three instruments. We found that flautists and trumpeters could discriminate smaller differences in pitch for artificial flat-spectrum tones, despite their unfamiliar timbre, than for sounds played by musical instruments, which are regularly heard in everyday life (particularly by musicians who play those instruments). Furthermore, thresholds were no better for the instrument a musician was trained to play than for other instruments, suggesting that even extensive experience listening to and producing sounds of particular timbres does not reliably improve pitch discrimination thresholds for those timbres. The results show that timbre familiarity provides minimal improvements to auditory acuity, and physical acoustics (e.g., the presence of equal-amplitude harmonics) determine pitch discrimination thresholds more than does experience with natural sounds and timbre-specific training.
The Utility of Mixed Models in Sport Science: A Call for Further Adoption in Longitudinal Data Sets
Authors: Newans Tim , Bellinger Phillip , Drovandi Christopher , Buxton Simon , Minahan Clare
Published: July 2022

Purpose: Sport-science research consistently contains repeated measures and imbalanced data sets. This study calls for further adoption of mixed models when analyzing longitudinal sport-science data sets. Mixed models were used to understand whether the level of competition affected the intensity of women’s rugby league match play. Methods: A total of 472 observations were used to compare the mean speed of female rugby league athletes recorded during club-, state-, and international-level competition. As athletes featured in all 3 levels of competition and there were multiple matches within each competition (ie, repeated measures), the authors demonstrated that mixed models are the appropriate statistical approach for these data. Results: The authors determined that if a repeated-measures analysis of variance (ANOVA) were used for the statistical analysis in the present study, at least 48.7% of the data would have been omitted to meet ANOVA assumptions. Using a mixed model, the authors determined that mean speed recorded during Trans-Tasman Test matches was 73.4 m·min−1, while the mean speeds for National Rugby League Women and State of Origin matches were 77.6 and 81.6 m·min−1, respectively. Random effects of team, athlete, and match all accounted for variations in mean speed, which otherwise could have concealed the main effects of position and level of competition had less flexible ANOVAs been used. Conclusion: These data clearly demonstrate the appropriateness of applying mixed models to typical data sets acquired in the professional sport setting. Mixed models should be more readily used within sport science, especially in observational, longitudinal data sets such as movement pattern analyses.
Competing and accelerating effects of anthropogenic nutrient inputs on climate-driven changes in ocean carbon and oxygen cycles
Authors: Yamamoto Akitomo , Hajima Tomohiro , Yamazaki Dai , Noguchi Aita Maki , Ito Akinori , Kawamiya Michio
Published: July 2022

Nutrient inputs from the atmosphere and rivers to the ocean are increased substantially by human activities. However, the effects of increased nutrient inputs are not included in the widely used CMIP5 Earth system models, which introduce bias into model simulations of ocean biogeochemistry. Here, using historical simulations by an Earth system model with perturbed atmospheric and riverine nutrient inputs, we show that the contribution of anthropogenic nutrient inputs to past global changes in ocean biogeochemistry is of similar magnitude to the effect of climate change. Anthropogenic nutrient inputs increase oceanic productivity and carbon uptake, offsetting climate-induced decrease and accelerating climate-driven deoxygenation in the upper ocean. Moreover, accounting for anthropogenic nutrient inputs improves the known carbon budget imbalance and model underestimation of the observed decrease in the global oxygen inventory. Considering the effects of both nutrient inputs and climate change is crucial in assessing anthropogenic impacts on ocean biogeochemistry.
Ambient formaldehyde and mortality: A time series analysis in China
Authors: Ban Jie , Su Wenjing , Zhong Yu , Liu Cheng , Li Tiantian
Published: July 2022

The potential health impact of low-level ambient formaldehyde has been historically overlooked. We conducted a two-stage time series analysis to investigate associations between ambient formaldehyde and daily nonaccidental, circulatory, and respiratory mortality and six subtypes based on 5,325,585 deaths in 275 Chinese counties between 2013 and 2018 and estimated a concentration-response curve to identify overall associations. After controlling for confounders from meteorological factors, air pollutants, time trend, and day of the week effect, with a 1–part per billion (ppb) increase in the daily concentration of formaldehyde on lag0 day, we found that mortality risks in nonaccidental, circulatory, and respiratory diseases increased by 0.36%, 0.36% and 0.41%, respectively. The curve indicated a possible threshold concentration at approximately 5 ppb for significant impact on nonaccidental and circulatory diseases. We suggest that ambient formaldehyde may represent a potential threat to public health and needs further investigation to support timely pollution regulation and health protection.
Arctic ice and the ecological rise of the dinosaurs
Authors: Olsen Paul , Sha Jingeng , Fang Yanan , Chang Clara , Whiteside Jessica H. , Kinney Sean , Sues Hans-Dieter , Kent Dennis , Schaller Morgan , Vajda Vivi
Published: July 2022

Abundant lake ice-rafted debris in Late Triassic and earliest Jurassic strata of the Junggar Basin of northwestern China (paleolatitude ~71°N) indicates that freezing winter temperatures typified the forested Arctic, despite a persistence of extremely high levels of atmospheric
P
co
2
(partial pressure of CO
2
). Phylogenetic bracket analysis shows that non-avian dinosaurs were primitively insulated, enabling them to access rich deciduous and evergreen Arctic vegetation, even under freezing winter conditions. Transient but intense volcanic winters associated with massive eruptions and lowered light levels led to the end-Triassic mass extinction (201.6 Ma) on land, decimating all medium- to large-sized nondinosaurian, noninsulated continental reptiles. In contrast, insulated dinosaurs were already well adapted to cold temperatures, and not only survived but also underwent a rapid adaptive radiation and ecological expansion in the Jurassic, taking over regions formerly dominated by large noninsulated reptiles.
Androgen effects cause sex-biased impairment of CD8
+
T cell antitumor activity
Authors: Bevilacqua Alessio , Ho Ping-Chih
Published: July 2022

Androgen signaling compromises CD8
+
T cell effector functions and contributes to sex-biased outcomes in many forms of cancer (see the related Research Article by Kwon
et al.
).
Experimental Implementation of the Method of Generation of a Sequence of Ultrashort Gigawatt Cherenkov Superradiance Pulses with a Nanosecond Repetition Period
Authors: Totmeninov E. M. , Konev V. Yu. , Klimov A. I. , Pegel I. V.
Published: July 2022

A periodic sequence of ultrashort superradiance pulses during the current pulse of an electron beam with a duration of about 40 ns has been generated in an experiment with a relativistic backward-wave oscillator with wave reflectors at the edges of the electron–wave interaction region. The pulse repetition period has been specified by the electron–wave feedback time and is 5.9 ns, which corresponds to the repetition frequency of 170 MHz at a FWHM duration of about 0.8 ns. The frequency of microwave oscillations is 10 GHz. The peak power of pulses is 0.8–1.3 GW. The corresponding conversion coefficients defined as the ratio of the peak power of the ultrashort microwave pulse to the power of the electron beam are 0.7–1.2.
Bremsstrahlung at the Nonresonant Inelastic Scattering of a Photon by an Atomic Ion
Authors: Hopersky A. N. , Nadolinsky A. M.
Published: July 2022

The analytical structure, absolute value, and angular anisotropy of the double differential cross section for bremsstrahlung at the nonresonant inelastic scattering of an X-ray photon by a multicharged helium-like atomic ion have been theoretically predicted.
Phase 1B study of the safety and tolerability of the mineralocorticoid fludrocortisone acetate in patients with geographical atrophy
Authors: Hong Thomas , Chang Andrew , Maddess Ted , Provis Jan , Penfold Philip
Published: July 2022

Objective

To evaluate the safety and tolerability of a mineralocorticoid, in a single-dose intravitreal (IVT) injection of 1 mg/0.1 mL and 2 mg/0.1 mL fludrocortisone acetate (FCA) in subjects with geographical atrophy (GA) secondary to age-related macular degeneration.

Methods and Analysis

This phase 1b study was a two-part dose-escalation prospective study. Part 1 involved a single participant treated with 1 mg/0.1 mL and monitored up to 28 days before being reviewed by a safety review committee. Two subsequent participants were then dosed with the same dose. Part 2 involved a single participant dosed with 2 mg/0.1 mL and monitored up to 28 days when a further five participants were dosed. All participants were followed up for 6 months after baseline.

A full ophthalmic assessment was performed at study visits which included GA area, best-corrected visual acuity (BCVA), low-luminance BCVA (LL-BCVA) and intraocular pressure (IOP). Adverse events (AEs) were reported from the first dose of FCA until the end-of-study visit.

Results

There were no serious AEs (ocular or systemic) observed with IVT FCA at either 1 mg/0.1 mL or 2 mg/0.1 mL among nine participants. There was no evidence of increased IOP or cataract development.

Neither BCVA or LL-BCVA changed significantly in the study-eye over the follow-up period (p=0.28 and 0.38, respectively). Mean GA area increased in the study (0.5 mm2, p=0.003) and fellow-eyes (0.62 mm2, p=0.02) over 6 months. Differences between eyes were not significant (p=0.64), and at the lower end of population norms.

Conclusion

IVT FCA is clinically safe and well tolerated and did not increase IOP.