bluuebunny/crossref_metadata_2025 huggingface dataset:
Post‐vaccination serologic testing of infants born to hepatitis B surface antigen‐positive mothers is more cost‐effective in Zhejiang Province, China: A Markov chain analysis
Authors: Lu Zhaojun , Zhou Yang , Yan Rui , Deng Xuan , Tang Xuewen , Zhu Yao , Xu Xiaoping , Zheng Weijun , He Hanqing
Published: January 2022

To evaluate the cost‐effectiveness of the post‐vaccination serologic testing (PVST) plus active‐passive immunoprophylaxis of infants born to hepatitis B surface antigen (HBsAg)‐positive mothers, a Markov model was constructed by R 4.0.1 to compare the current strategy (three‐dose HepB plus HBIG) and the PVST strategy (post‐vaccination serologic testing plus the current strategy) for infants of HBsAg‐positive mothers. Costs and utility scores were assessed from a field survey. Other model inputs were extracted from published literature and unpublished data from the Zhejiang provincial center for disease control and prevention (Zhejiang CDC). We calculated the incremental cost‐effectiveness ratio (ICER) as the main result within 1‐year cycle length with a 81 horizon among 50,000 infants and performed one‐way sensitivity analysis and probabilistic sensitivity analysis to explore the reliability of outcome. The ICER was −4130.18 yuan/quality‐adjusted life year (QALY) for the PVST strategy compared with the current strategy from the societal perspective. It was estimated that the PVST strategy would save about 3,809,546 yuan and prevent loss of 922.37 QALYs within 81 cycles among 50,000 infants. ICER was most sensitive to the discount rate, and the cost‐effectiveness acceptability curves showed that the PVST strategy reached a probability of being 100% cost‐effective below willing to pay (107,624 yuan). In conclusion, the PVST strategy had increased the utility and reduced cost among infants born to HBsAg‐positive mothers. The PVST strategy is a more cost‐effective choice for infants born to HBsAg‐positive mothers than the current strategy, and further promotion of the PVST project is recommended.
Meta‐analysis shows both congruence and complementarity of DNA and eDNA metabarcoding to traditional methods for biological community assessment
Authors: Keck François , Blackman Rosetta C. , Bossart Raphael , Brantschen Jeanine , Couton Marjorie , Hürlemann Samuel , Kirschner Dominik , Locher Nadine , Zhang Heng , Altermatt Florian
Published: January 2022

DNA metabarcoding is increasingly used for the assessment of aquatic communities, and numerous studies have investigated the consistency of this technique with traditional morpho‐taxonomic approaches. These individual studies have used DNA metabarcoding to assess diversity and community structure of aquatic organisms both in marine and freshwater systems globally over the last decade. However, a systematic analysis of the comparability and effectiveness of DNA‐based community assessment across all of these studies has hitherto been lacking. Here, we performed the first meta‐analysis of available studies comparing traditional methods and DNA metabarcoding to measure and assess biological diversity of key aquatic groups, including plankton, microphytobentos, macroinvertebrates, and fish. Across 215 data sets, we found that DNA metabarcoding provides richness estimates that are globally consistent to those obtained using traditional methods, both at local and regional scale. DNA metabarcoding also generates species inventories that are highly congruent with traditional methods for fish. Contrastingly, species inventories of plankton, microphytobenthos and macroinvertebrates obtained by DNA metabarcoding showed pronounced differences to traditional methods, missing some taxa but at the same time detecting otherwise overseen diversity. The method is generally sufficiently advanced to study the composition of fish communities and replace more invasive traditional methods. For smaller organisms, like macroinvertebrates, plankton and microphytobenthos, DNA metabarcoding may continue to give complementary rather than identical estimates compared to traditional approaches. Systematic and comparable data collection will increase the understanding of different aspects of this complementarity, and increase the effectiveness of the method and adequate interpretation of the results.
Single‐cell RNA‐sequencing of Nicotiana attenuata corolla cells reveals the biosynthetic pathway of a floral scent
Authors: Kang Moonyoung , Choi Yuri , Kim Hyeonjin , Kim Sang‐Gyu
Published: January 2022

High‐throughput single‐cell RNA sequencing (scRNA‐Seq) identifies distinct cell populations based on cell‐to‐cell heterogeneity in gene expression. By examining the distribution of the density of gene expression profiles, we can observe the metabolic features of each cell population.

Here, we employ the scRNA‐Seq technique to reveal the entire biosynthetic pathway of a flower volatile.

The corolla of the wild tobacco Nicotiana attenuata emits a bouquet of scents that are composed mainly of benzylacetone (BA). Protoplasts from the N. attenuata corolla limbs and throat cups were isolated at three different time points, and the transcript levels of > 16 000 genes were analyzed in 3756 single cells.

We performed unsupervised clustering analysis to determine which cell clusters were involved in BA biosynthesis. The biosynthetic pathway of BA was uncovered by analyzing gene co‐expression in scRNA‐Seq datasets and by silencing candidate genes in the corolla.

In conclusion, the high‐resolution spatiotemporal atlas of gene expression provided by scRNA‐Seq reveals the molecular features underlying cell‐type‐specific metabolism in a plant.
SAMDC3 enhances resistance to Barley stripe mosaic virus by promoting the ubiquitination and proteasomal degradation of viral γb protein
Authors: Li Zhaolei , Yang Xinxin , Li Wenli , Wen Zhiyan , Duan Jiangning , Jiang Zhihao , Zhang Dingliang , Xie Xialin , Wang Xueting , Li Fangfang , Li Dawei , Zhang Yongliang
Published: January 2022

Posttranslational modifications (PTMs) play important roles in virus–host interplay. We previously demonstrated that Barley stripe mosaic virus (BSMV) γb protein is phosphorylated by different host kinases to support or impede viral infection. However, whether and how other types of PTMs participate in BSMV infection remains to be explored.

Here, we report that S‐adenosylmethionine decarboxylase 3 (SAMDC3) from Nicotiana benthamiana or wheat (Triticum aestivum) interacts with γb. BSMV infection induced SAMDC3 expression. Overexpression of SAMDC3 led to the destabilization of γb and reduction in viral infectivity, whereas knocking out NbSAMDC3 increased susceptibility to BSMV.

NbSAMDC3 positively regulated the 26S proteasome‐mediated degradation of γb via its PEST domain. Further mechanistic studies revealed that γb can be ubiquitinated in planta and that NbSAMDC3 promotes the proteasomal degradation of γb by increasing γb ubiquitination. We also found evidence that ubiquitination occurs at nonlysine residues (Ser‐133 and Cys‐144) within γb.

Together, our results provide a function for SAMDC3 in defence against BSMV infection through targeting of γb abundance, which contributes to our understanding of how a plant host deploys the ubiquitin–proteasome system to mount defences against viral infections.
Tinea capitis: An update
Authors: Gupta Aditya K. , Friedlander Sheila Fallon , Simkovich Aaron J.
Published: January 2022

Tinea capitis is an important superficial infection and affects children globally. A literature review was conducted to identify recent findings and the current understanding of this fungal infection. Here, we highlight updates on important aspects of tinea capitis including advances in dermatophyte detection and diagnosis and comparing these new methods to more traditional techniques. Additionally, aspects of treating tinea capitis are discussed, including the importance of mycological confirmation and current means of treatment, and the treatment of asymptomatic carriers are reviewed. This review also examines the subject of laboratory monitoring of patients undergoing treatment with systemic antifungals; we discuss the opinions of prominent researchers and currently accepted guidelines. Lastly, we provide answers to several common questions that practitioners may encounter when treating a child with tinea capitis.
Introduction to biological rhythms: A brief history of chronobiology and its relevance to parasite immunology
Authors: Ince Louise Madeleine
Published: January 2022

Almost every living organism on earth is exposed to a fluctuating environment, for example, light:dark cycles, food availability and seasonal photoperiods. Most species have therefore evolved internal timing mechanisms allowing them to anticipate these rhythmic environmental changes, obtaining a survival advantage. Circadian (24 h) rhythms, in particular, regulate multiple aspects of physiology, including sleep/wake activity, feeding rhythms and immune function. Recent studies have identified circadian rhythms in symptoms of parasite infections, rhythms in parasite schizogony and evidence that certain parasites can manipulate host rhythms. Furthermore, efficacy of anti‐parasite medications can also be modulated by timing of drug administration. Understanding the interactions between host rhythms, parasite rhythms and disease severity is crucial to fully understand how to combat infections and reduce pathology. The aim of this review is, therefore, to provide an introduction to the field of biological rhythms, give a brief history of chronobiology research and discuss the relevance of biological rhythms to parasite immunology.
Parallel imports of status goods: A strategic analysis of aesthetic design
Authors: Li Krista J. , Zhang Jianqiang , Schaefer Richard
Published: January 2022

Parallel imports of gray products across markets are a worldwide concern for manufacturers. Extant research has focused on parallel imports of regular goods that do not provide status value. In this paper, we investigate parallel imports of conspicuously consumed status goods. We consider a manufacturer who directly sells a status product to consumers in two markets that value the product differently and a gray marketer that can import the product across markets. Our analysis shows that, though parallel imports decrease a manufacturer's profit from selling regular goods, it can increase their profit from selling status goods. Furthermore, the manufacturer decides whether to use the same or different aesthetic design for products across markets. With the same design, the gray and manufacturer‐authorized products look identical, while different designs make them distinguishable, which affects their status value. We find that parallel imports benefit the manufacturer in a broader range of situations under the different‐design strategy, whereas the same‐design strategy increases the gray marketer's profit. When the two markets are sufficiently similar, the manufacturer uses the same design to induce parallel imports. When the two markets are sufficiently different, the manufacturer uses different designs to either deter parallel imports or improve their profit while competing with the gray marketer.
Racial, ethnic and socioeconomic disparities in SARS‐CoV‐2 infection amongst children
Authors: Mannheim Jonathan , Konda Sreenivas , Logan Latania K.
Published: January 2022

Background

COVID‐19 disproportionately affects racial and ethnic minority populations, but comparatively few epidemiologic studies have been performed on children as compared to adults.

Objectives

To characterise factors associated with SARS‐CoV‐2 infections amongst children from Chicago, Illinois, USA.

Methods

A test‐negative case‐control study of children tested for SARS‐CoV‐2 (0–18 years) at three medical centres of the Rush University System for Health between 12 March and 7 December 2020 was conducted. Of 8462 children, 1,302 tested positive by real‐time PCR or rapid (NAAT) testing. Infection with SARS‐CoV‐2 was analysed as the outcome variable; effects of predictors were assessed by logistic regression analysis. A Paediatric Risk Score Index with a concordance index of 72% of accuracy was created to predict SARS‐CoV‐2 infection.

Results

The median age of cases was 13 years. On multivariable analysis, factors associated with SARS‐CoV‐2 infection were being Hispanic/Latinx (odds ratio [OR] 2.45, 95% CI 1.99, 3.03); Black/African‐American (OR 1.31, 95% CI 1.03, 1.66); overweight/obese (OR 1.27, 95% CI 1.02, 1.58); older age, 10–14 years (OR 1.70, 95% CI 1.39, 2.08), 15–18 years (OR 2.06, 95% CI 1.71, 2.47); from households with income <$50,000 (OR 1.36, 95% CI 1.17, 1.60); or residing in predominantly minority neighbourhoods (OR 1.45, 95% CI 1.17, 1.80). Infections were higher during the second “fall” wave (5 October 2020 onward) compared with the first “spring” wave (OR 2.30, 95% CI 2.01, 2.63). Within Chicago, racial/ethnic minority neighbourhoods had striking positivity rates, as high as 39% in majority Hispanic/Latinx West Lawn neighbourhood. In suburban Chicago, highest positivity rates (20%–28%) were in zip codes within Hispanic/Latinx communities.

Conclusions

Infection with SARS‐CoV‐2 is more likely amongst children of Hispanic/Latinx ethnicity, Black/African‐American race, aged 10–18 years, who are overweight/obese, from lower income households, and from minority neighbourhoods. Future studies should focus on the prevention of COVID‐19 infection in children of highest risk.
Non‐gonadal linear type traits can discriminate reproductive ability of breeding dairy bulls
Authors: Mandal Dilip Kumar , Kumar Mahesh , Tyagi Shrikant
Published: January 2022

Linear type traits are easily measurable phenotypic characteristics that help breed characterization, selection of animals for breeding and found to be associated with animals’ performance. Unlike cows, there have been limited studies linking body linear traits with male reproductive ability and semen cryo‐preservability of breeding bulls. Present study reported the age‐related changes in body linear type traits in Frieswal (N = 378) dairy bulls and its relevance with reproductive potentials of breeding bulls. Our results indicated that body frame size traits were significantly and positively correlated with gonadal linear traits. Among the selected body mophometric parameters body length, chest girth and head circumference were the important body linear type traits having capability to discriminate between bulls of frozen semen doses (FSD) and non‐FSD categories. Discriminant function has been developed based on body linear traits of crossbred dairy bulls to find out males of superior reproductive potentials. Our finding provided evidence that body length (humerous tuberosity to tuber ischii) was the most powerful linear body trait associated with breeding bulls’ reproductive ability and semen quality.
Opening opportunities for women in respiratory medicine: Letter from Korea
Authors: Kang Young Ae , Jung Ji Ye
Published: January 2022

See related editorial
Perfectionism dimensions: A network analysis of their relationships with affect and obsessive–compulsive pathological personality traits
Authors: Mansur‐Alves Marcela , Machado Gisele Magarotto , Rodrigues Willian de Sousa , Neufeld Carmem Beatriz , Carvalho Lucas de Francisco
Published: January 2022

This study investigated the associations of multidimensional perfectionism with positive affect and negative outcomes (affect and Obsessive–Compulsive Personality Disorder [OCPD] pathological traits) through network analysis. The sample consisted of 604 Brazilian adults aged 18–74 years. The network analysis showed that perfectionistic concerns (PC) is strongly and positively associated with negative outcomes, while perfectionistic strivings (PS) maintain positive associations with positive affect, but not negative affect. Negative affect seems to operate as a bridge between perfectionism and OCPD pathological traits, raising crucial questions about the antecedent and consequential role of affect for understanding perfectionism's development and the traits observed in individuals with OCPD. We discuss the limitations and strengths of the study.
Segregation of the membrane cargoes, BACE1 and amyloid precursor protein (APP) throughout the Golgi apparatus
Authors: Fourriere Lou , Cho Ellie Hyun‐Jung , Gleeson Paul A.
Published: January 2022

The intracellular trafficking of β‐site amyloid precursor protein (APP) cleaving enzyme (BACE1) and APP regulates amyloid‐β production. Our previous work demonstrated that newly synthesized BACE1 and APP are segregated into distinct trafficking pathways from the trans‐Golgi network (TGN), and that alterations in their trafficking lead to an increase in Aβ production in non‐neuronal and neuronal cells. However, it is not known whether BACE1 and APP are transported through the Golgi stacks together and sorted at the TGN or segregated prior to arrival at the TGN. To address this question, we have used high‐resolution Airyscan technology followed by Huygens deconvolution to quantify the overlap of BACE1 and APP in Golgi subcompartments in HeLa cells and primary neurons. Here, we show that APP and BACE1 are segregated, on exit from the endoplasmic reticulum and in the cis‐Golgi and throughout the Golgi stack. In contrast, the transferrin receptor, which exits the TGN in AP‐1 mediated transport carriers as for BACE1, colocalizes with BACE1, but not APP, throughout the Golgi stack. The segregation of APP and BACE1 is independent of the Golgi ribbon structure and the cytoplasmic domain of the cargo. Overall, our findings reveal the segregation of different membrane cargoes early in the secretory pathway, a finding relevant to the regulation of APP processing events.
The dendritic ERGIC: Microtubule and actin cytoskeletons participate in stop‐and‐go movement of mobile carriers between stable structures
Authors: de los Ángeles Juricic Urzúa María , Rojas Javiera Gallardo , Correa Andrés Couve , Cerda Mauricio , Gründler Steffen Härtel , González‐Silva Carolina
Published: January 2022

The endoplasmic reticulum (ER)‐to‐Golgi intermediate compartment (ERGIC) is a membranous organelle that mediates protein transport between the ER and the Golgi apparatus. In neurons, clusters of these vesiculotubular structures are situated throughout the cell in proximity to the ER, passing cargo to the cis‐Golgi cisternae, located mainly in the perinuclear region. Although ERGIC markers have been identified in neurons, the distribution and dynamics of neuronal ERGIC structures have not been characterized yet. Here, we show that long‐distance ERGIC transport occurs via an intermittent mechanism in dendrites, with mobile elements moving between stationary structures. Slow and fast live‐cell imaging have captured stable ERGIC structures remaining in place over long periods of time, as well as mobile ERGIC structures advancing very short distances along dendrites. These short distances have been consistent with the lengths between the stationary ERGIC structures. Kymography revealed ERGIC elements that moved intermittently, emerging from and fusing with stationary ERGIC structures. Interestingly, this movement apparently depends not only on the integrity of the microtubule cytoskeleton, as previously reported, but on the actin cytoskeleton as well. Our results indicate that the dendritic ERGIC has a dual nature, with both stationary and mobile structures. The neural ERGIC network transports proteins via a stop‐and‐go movement in which both the microtubule and the actin cytoskeletons participate.
Mitogenomic phylogeny resolves Cuneopsis (Bivalvia: Unionidae) as polyphyletic: The description of two new genera and a new species
Authors: Wu Xiao‐Ping , Dai Yu‐Ting , Yin Nan , Shu Feng‐Yue , Chen Zhong‐Guang , Guo Liang , Zhou Chun‐Hua , Ouyang Shan , Huang Xiao‐Chen
Published: January 2022

Freshwater mussels are known to have two types of mitochondrial DNA (mtDNA) transmitted separately through oocytes and sperms, namely, maternal (F‐type) and paternal (M‐type) mtDNA. The additional suite of mitochondrial genes provides a great opportunity to resolve phylogenetically problematic relationships. East Asian freshwater mussels of the genus Cuneopsis were considered a compact group of taxa having wedge‐shaped shells. However, preliminary results from previous studies challenged the monophyly of Cuneopsis, and the exact phylogenetic relationships among Cuneopsis and its allied genera are yet to be determined with comprehensive species sampling. Here, we evaluated species boundaries in Cuneopsis based on COI barcoding and obtained 11 new F‐ and M‐type mitogenomes via genome skimming to elucidate the evolutionary history of Cuneopsis. COI barcode data supported the validity of all sampled six Cuneopsis species (missing C. kiangsiensis). Our mitochondrial phylogenomic analyses confirmed that the currently recognized genus Cuneopsis sensu lato was polyphyletic, recovering three well‐supported clades. Molecular dating analysis suggested Cuneopsis s.l. diversified at ~58.06 million years ago in the Paleogene. Hereby, we propose two new genera, that is, Arcuneopsis gen. nov. and Pseudocuneopsis gen. nov. Additionally, we report a new species, Pseudocuneopsis sichuanensis sp. nov., from Chengdu, Sichuan, China, and a newly recorded species from China, Cuneopsis demangei.
Experimental and Theoretical Pressures and Velocity Fields for Various Lead Extrusions
Authors: Thomsen E. G. , Frisch J.
Published: January 2022

Extrusion pressures and velocity fields were determined for inverted extrusion processes of commercially pure lead. The extrusion ratios were varied from 1.51 to 18.5 (33.7 per cent to 94.6 per cent reduction). It was found that, for both low and high friction at cylinder wall and at die surfaces, qualitative agreement exists between slip-line solutions and experiment.
An Experimental Study on Chatter Vibrations in Grinding Operations
Authors: Doi S.
Published: January 2022

During the grinding process there frequently occurs a lateral vibration of the rotating wheel. In this experiment that vibration was magnified under the microscope and measured on a rotating film. Many modes of vibration were ascertained experimentally, produced by irregularity of the journal of the main spindle; peripheral irregularity of the grinding wheel; a flexible main spindle; clearance in the main bearing; the driving-belt seam and the flapping vibration of the driving belt on the main spindle; a flexible workpiece; the deflection of a grinding machine, and so on. The causes and the characters of these vibrations and some preventative methods were investigated. It has been found that a plain bearing used as the main bearing of a grinder is superior to a ball bearing in so far as prevention of vibration of the wheel is concerned.
A Method for Calculating Vibration Frequency and Stress of a Banded Group of Turbine Buckets
Authors: Prohl M. A.
Published: January 2022

Steam-turbine buckets are normally covered at the tips by a band. The band is applied in segments, each segment elastically joining together a given number of buckets. In studying vibrational behavior the buckets should be treated as banded groups rather than as individual cantilevers. A method of analysis, suitable for digital computation, is presented which gives all of the natural frequencies and mode shapes of a banded group of buckets subject to the usual limitations of the elementary beam theory. Axial and torsional motion as well as tangential is considered. Also a procedure is included for evaluating vibration amplitude and stress at resonance. Damping is assumed to be small and the energy input to the banded group from a prescribed form of nozzle stimulus is equated to the energy dissipated in damping to determine vibration-stress levels. Sample calculations have been made on the I.B.M. Electronic Data Processing Machine, Type 704, and the results of these calculations are given in a companion paper (1).
High-Frequency Vibration of Steam-Turbine Buckets
Authors: Weaver F. L. , Prohl M. A.
Published: January 2022

The design of short and medium-height steam-turbine buckets is discussed with regard to the possibility of resonant vibration at the frequency of passing nozzles or multiples of this frequency. Particular attention is given to the design problems involved in marine applications. A new calculation procedure (1) is used to obtain the various natural frequencies (tangential, axial, and torsional) of a banded group of buckets and the related mode forms and vibration-stress levels. Calculation results obtained on the IBM Electronic Data Processing Machine, Type 704, are presented and are discussed with relation to their influence on bucket design.
The Formation of Sulphuric Acid in Boiler Flue Gases
Authors: Harlow W. F.
Published: January 2022

The discovery of the mechanism for the formation of sulphuric acid in flue gases of modern boiler plants by the process of surface catalysis, brought about by the heating surface over which the gases pass, was published some years ago. Notwithstanding the evidence put forward at that time, both from fundamental tests and operating plants, controversy on the question continues and little progress has been made in the suppression of this harmful product which is responsible for the deposit and corrosion on the boiler-plant surfaces and is, moreover, a very destructive and undesirable contaminant of the atmosphere. This paper describes further work on the subject, including tests which leave the explanation in no reasonable doubt and shows the effect on the sulphuric-acid formation of various surface treatments of the heating surface—both metallurgical and chemical.
Concurrent Flow of Air, Gas-Oil, and Water in a Horizontal Pipe
Authors: Sobocinski D. P. , Huntington R. L.
Published: January 2022

There are several operations in the production of petroleum in which three-phase concurrent flow of fluids takes place. In some cases this type of flow necessarily must occur, such as the lifting and transportation of gas, crude oil, or condensate and water from the reservoir to the first separator in the field. In another operation, three-phase flow is encountered when glycol is injected into a pipeline at the well-head with oil and wet gas, in order to prevent freeze ups from gas-hydrate formation. The design of piping for vertical, horizontal, and inclined multiphase flow has been done largely by the expensive route of trial and error. Poettman, et al., have analyzed data on a number of wells flowing oil, gas, and water vertically. This laboratory study was undertaken in view of the current interest in the concurrent flow of oil and gas in field-gathering pipelines along with the injection of a third water phase such as glycol.
Designing Thermocouples for Response Rate
Authors: Moffat R. J.
Published: January 2022

Accurate information about thermocouple response rate is of value both to the designer of engine controls and to the test engineer. The response performance of a probe can be described in terms of its “characteristic time,” which can be determined experimentally. The characteristic time of a probe is not a constant, but is affected by the mass velocity and temperature of the gas stream in which it is used. Analysis of experimental data resulted in an empirical equation for characteristic time in terms of the geometry and flow conditions. This equation predicts the characteristic time within 10 per cent for bare wireloop-junction thermocouples from 0.016 to 0.051-in-diam wire, mass velocities from 3 to 50 lb/sec ft2 and temperature from 160 to 1600 F. All data were taken at a static pressure of 1 atm. The effects of manufacturing tolerances and engine environmental conditions also have been investigated. Data are presented concerning the effect of junction-weld bead size, junction exposed length, junction orientation, and radiative heat transfer from the junction.
A Tool-Work-Thermocouple Compensating Circuit
Authors: Trigger K. J. , Campbell R. K. , Chao B. T.
Published: January 2022

A compensating circuit which facilitates the use of the tool-work thermocouple for interface-temperature measurements is presented. The IR drop due to the flow of thermoelectric current in a closed circuit is used to nullify the parasitic emf introduced by dissimilar lead materials attached to the cutting insert. Conditions necessary to achieve complete compensation are explained and test results indicating the reliability of the method are given.
Temperature Distribution at Tool-Chip and Tool-Work Interface in Metal Cutting
Authors: Chao B. T. , Trigger K. J.
Published: January 2022

A noniterative method is presented for the computation of temperature distribution both at the tool-chip and tool-work interface in metal cutting. Temperatures at the tool-work interface increase appreciably with the increase in flank wear. This phenomenon contrasts to the relatively minor influence on tool-chip interface temperature as crater wear develops. Results include a three-dimensional temperature distribution at the tool top surface.
The Biotechnical Problem of the Human Body as a Heat Exchanger
Authors: Herrington L. P.
Published: January 2022

The physical and engineering properties of inanimate objects as heat exchangers have been the subject of long study. Within the past 25 years, many factors have brought biological disciplines into intimate contact with the formally similar problem of heat exchange between a living body and its environment. A Committee on Biotechnology of the Heat Transfer Division of this Society has been organized recently with the intention of advancing and standardizing useful engineering descriptions of biological heat-exchange problems. Such problems presently complicate engineering design in which the human link is a critical element in total function of man and machine. The paper demonstrates that a large body of calorimetric data on the human heat exchanger can be summarized in statistically derived empirical equations. These equations obviate the need for special physiological knowledge required of the engineer who would make such computations from the classical equations of heat loss.
Heat Transfer Between a Flat Plate and a Fluid Containing Heat Sources
Authors: Whiteman I. R.
Published: January 2022

The Leveque solution for the case of a fluid flowing past a flat plate has been expanded to include the presence of heat sources in the fluid. Through the use of certain approximations, an expression has been obtained for the heat flux through the plate for given plate temperature and source, and an expression for the plate temperature for given heat flux and source.
A Simple Formula for Determining the Position of Maximum Slider Velocity in a Slider-Crank Mechanism
Authors: Ip Ching-U , Price L. C.
Published: January 2022

A cubic equation which gives the position of maximum slider velocity is derived. The equation lends itself readily to be solved to any desired degree of accuracy by Lin’s method. A simple formula is found to furnish a closed-form answer which is accurate within 4 min of a degree for l/r ratio of 1.5, and has practically no error for l/r greater than 5. The results are compared with those obtained from the familiar approximate slider-velocity formula having a second harmonic.
Optimization of Time-Varying Linear Systems With Nonstationary Inputs
Authors: Shinbrot Marvin
Published: January 2022

A method is presented for solving the integral equation which arises in optimization problems with nonstationary inputs. The method depends on the correlation functions being of a certain type—fortunately, a type which arises frequently in practice. The sort of problem which can be handled and the associated results are illustrated by examples.
Correlation Functions and Noise Patterns in Control Analysis
Authors: Thal-Larsen Herman
Published: January 2022

This paper describes the interplay of disturbance patterns and correlation functions when “noise” enters a control system, both in the fictitious case of the mathematical model and in the real process. In pointing out this interplay in the model and again in the real process, the application of correlation functions to control analysis is shown to have its limitations. At the same time the importance of discovering equivalent disturbance patterns is emphasized and a procedure for their discovery is developed.
Dynamic Study of an Experimental Pneumatic Process-Pressure Transmitter
Authors: Hochschild E. F.
Published: January 2022

A dynamic analysis and synthesis study of a highly accurate pressure-measuring instrument is presented. Emphasis is placed on methods, techniques, and the experience gained during the course of the investigation. Use of network theorems and the mobility method permits a simple analysis of a complex mechanical-pneumatic device. The effects on the transmitter resulting from tubing load are treated in detail. An electronic analog simulation, incorporating a transmitter nonlinearity, is used in the final synthesis for obtaining the required dynamic performance. Experimental and calculated frequency responses are compared and excellent correlation is shown.
Recovery Ratio—A Measure of the Loss Recovery Potential of Compressor Stages
Authors: Smith Leroy H.
Published: January 2022

Certain types of axial-flow-compressor stage designs have the ability to add extra energy to high-loss regions of the inlet flow and thereby tend to smooth out inlet-flow distortion rapidly. A recovery ratio, which is believed to give a quantitative measure of this ability for radial (axisymmetric) distortions, is defined and expressed in terms of familiar stage parameters. It is found that the flow coefficient (meridional velocity/blade speed) should have a value near 0.5 or less, and that the stage loading should be light.
Overstrain and Bursting Strength of Thick-Walled Cylinders
Authors: Jorgensen S. M.
Published: January 2022

A description is given of the stress distribution in elastically strained and partially overstrained thick-walled cylinders, followed by a method of determining the most advantageous degree of overstrain. Ultimate strength is discussed and an empirical formula for the bursting strength is proposed.
Performance Factors of a Periodic-Flow Heat Exchanger
Authors: Lambertson T. J.
Published: January 2022

A numerical finite-difference method of calculating the effectiveness of the periodic-flow type heat exchanger is presented by considering the metal “stream” in crossflow with each of the gas streams as two separate but dependent exchangers. A general purpose digital computer was used to accommodate the large number of subdivisions necessary for accuracy and an extrapolation of data to zero element area such that the values of effectiveness are good to four significant figures. The exchanger effectiveness has been evaluated over the following range of dimensionless parameters 1.0⩾Cmin/Cmax⩾0.101.0⩽Cr/Cmin⩽∞1.0⩽NTUo⩽101.0⩾(hA)′⩾0.25
Dynamic Response of Heat Exchangers Having Internal Heat Sources—Part II
Authors: Arpaci V. S. , Clark J. A.
Published: January 2022

This paper considers the dynamic response of the temperature of the heat-transfer surface and the fluid-surface temperature difference in a heat exchanger having internal heat sources which is subjected to a sudden change in the rate of heat generation. The results are obtained by a direct mathematical attack on the governing differential equations. These are presented such that the surface temperature may be computed as a function of space and time using three mathematical functions obtained by IBM machine reduction. The theory is compared with experimental measurements and favorable agreement is obtained. Heat exchangers to which the solutions apply include the heterogeneous nuclear reactor.
Quasilinear Heat Flow
Authors: Friedmann N. E.
Published: January 2022

The influence of variation (with temperature) of thermal conductivity, density, and heat capacity at constant pressure on the solutions of the heat-conduction equation is considered. Several problems are solved by analog computation, for materials whose properties vary linearly with temperature, and the solutions of these are compared to analytical solutions. Analytical solutions also are obtained for problems involving materials which exhibit power-function-property variations with temperature. In all cases considered, the effects of property changes on calculated temperatures are found to be significant.
Gas-Friction—Heat Transfer Charts for Ducted Flows
Authors: Manson S. V.
Published: January 2022

Charts that speed heat-exchanger calculations and aid analysis of other ducted gas flows are illustrated and examples of their use are presented.
The Effect of Heat Conductance on Slider-Bearing Characteristics
Authors: Guilinger W. H. , Saibel E. A.
Published: January 2022

The slider bearing without side leakage is considered when heat generated in the oil film may be conducted in the fluid as well as lost to the surroundings, which are assumed held at fixed temperatures. The basic equations are reduced to a form suitable for calculation using a digital computer, and a procedure for carrying out these calculations is suggested together with error criteria.
Oil Seals to Provide Positive Lubrication on Large or High-Speed Thrust Bearings
Authors: Baudry R. A. , Peterson G. E. , Cooper G. D.
Published: January 2022

Vertical waterwheel generators are provided with large thrust bearings the surfaces of which are separated by a hydrodynamic oil film. In order to insure the formation of the required oil film, a continuous and sufficient supply of oil is required. With thrust bearings of increased size or speed, aeration of the oil may cause inadequate lubrication of the bearing surfaces or result in oil leakage. This paper discusses the application of positive oil seals which effectively prevent aeration of the oil and oil leakage.
Solution of Reynolds’ Equation for Finite Journal Bearings
Authors: Pinkus O.
Published: January 2022

Reynolds’ differential equation for finite bearings was solved for journal bearings having 100 and 75-deg arcs, using a digital computer. These results were applied to partial bearings as well as to 3-groove and 4-groove full journal bearings. Results are given for L/D ratios ranging from 1½ to ¼ and eccentricities up to 0.95. These results were correlated with previous results for different bearing arcs obtained by others and the author, to provide a comprehensive set of solutions of Reynolds’ equation for finite bearings from a full 360-deg arc down to an arc of 75 deg. Expressions for calculating minimum film thickness, total oil flow, power loss, and temperature rise also are given.
The Effect of Conduit Dynamics on Control-Valve Stability
Authors: Ezekiel F. D.
Published: January 2022

A method is presented for simulating the dynamic behavior of a frictionless hydraulic conduit with distributed parameters in conjunction with a simple spool-type control valve for analog-computer use. Analytical and experimental results showing the regions of stable and unstable operation of such a system are given, together with suggested stabilizing techniques. The effect of the valve chamber in the over-all analysis is found to be of considerable importance.
Work Capacities of Energy Storage Systems on Basis of Unit Weight and Unit Volume
Authors: Kline L. V. , Marco S. M. , Starkey W. L.
Published: January 2022

In view of current and anticipated interest in conserving weight and space in engineering applications, a study is made of work-per-unit-weight and work-per-unit-volume moduli for energy storage systems. Gasoline engines, solid propellants, electrochemical cells, flywheels, compressed gases, compressed liquids, and stressed solids are evaluated. General analytical expressions for the work moduli are derived. For each such general expression, significant optimizing parameters are selected and methods of optimizing the moduli are presented. Information is included pertinent to the problem of selection of energy storage systems for specific applications. Comparisons are made of the practical maximum values of weight and volume moduli for the considered systems. Limitations of the systems, including maximum allowable stress, are discussed.
Analysis of Residual Stress in Ground Surfaces of High-Temperature Alloys
Authors: Halverstadt R. D.
Published: January 2022

Residual stress caused by grinding high-temperature alloys has proved to be a troublesome problem both from a standpoint of distortion of the parts and from reduced endurance limits. A complete analysis was made which measured the effect of grinding-wheel speed, grinding-wheel hardness, grinding fluid, down feed, and work speed on the residual-stress level in the surface of three alloys used in modern aircraft gas-turbine design. The results of the study show that stresses can be minimized by using lower wheel speeds and down feeds, increasing work speed and using a sulfurized oil as the grinding fluid.
The Formulation of Steam Properties for Digital Computer Application
Authors: Steltz William G. , Silvestri George J.
Published: January 2022

Methods and equations are presented for approximating the properties of steam set forth in the Keenan and Keyes’ Steam Tables. Equations and functional relationships for derived thermodynamic properties as functions of basic independent variables are presented for compressed and saturated liquid, saturated and unsaturated vapor, and superheated steam. The thermodynamic properties, enthalpy and entropy, are described throughout while specific volume is determined only in the superheated steam region. Error plots of incremental differences from Keenan and Keyes’ values are shown as functions of the independent variables.
Problems in Measuring Steam Flow at 1250 Psia and 950 F With Nozzles and Orifices
Authors: Murdock J. W. , Goldsbury J.
Published: January 2022

Measurement of steam flow at 1250 psia and 950 F with nozzles and orifices is discussed (a) during their calibration and (b) during performance tests on a turbine. All primary elements were constructed to ASME specifications, the nozzles being of long-radius, low-ratio design with throat taps, the orifices employing radius taps.

The calibrations for the flow nozzles indicated that reliable repeatable results could be obtained although one nozzle exhibited an abrupt increase in discharge coefficient of about 0.5 per cent at about 2 per cent pressure differential. The measured coefficients of discharge were within Power Test Code “probable tolerances” of ±1.25 per cent. The calibrations of the orifices were of little value because of permanent distortion of the orifice plates as a result of difference in expansion between the plates and their holding flanges.

For measuring steam flows to the turbine, additional orifices were made up of different material, reducing distortion of the plates to the point of being negligible. The results of the turbine test with orifices and nozzles in series indicated excellent agreement between the flows based on orifice data using calculated coefficients and those determined from nozzle data using coefficients obtained from the calibration. Some trouble was experienced from deposits found around the nozzle throat taps.

While this paper presents data indicating excellent agreement of the two methods of flow measurement during the turbine-performance tests, it also points out the need for more experimentation and knowledge of steam-flow measurement at elevated temperatures and pressures.
The Dependence of Thermal Stresses in Cylindrical Reactor Fuel Elements Upon the Method of Cooling
Authors: Merckx K. R.
Published: January 2022

Thermal stresses and strains within cylindrical uranium-reactor fuel elements cooled by various methods are determined with a method of analysis which uses a material model relating the strain rate, temperature, strain, and stress. Solid and hollow cylindrical fuel elements internally, externally, and internally-externally cooled, operating in the temperature ranges of 200 to 600 C are used as numerical examples. For the cases with equal temperature drops, the stresses vary by 8 per cent while the plastic strains vary 140 per cent. The thermal stresses and strains in solid and hollow fuel elements externally and internally-externally cooled are compared for equal power generations. The maximum stress may be reduced 35 per cent and the maximum plastic strain 75 per cent if a solid fuel element is replaced by an internally-externally cooled fuel element (inner radius/outer radius = 0.4) producing the same power per foot.
Apparatus for the Experimental Study of the Thermodynamic Properties of Water
Authors: Reamer H. H. , Richter G. N. , DeWitt W. M. , Sage B. H.
Published: January 2022

As a part of an investigation of the properties of water at elevated temperatures and pressures, a study of the Joule-Thomson coefficient and the isothermal enthalpy-pressure derivative of steam has been undertaken. This experimental program is directed to the study of these coefficients at about temperatures between 400 F and 1500 F and at pressures up to 15,000 psi or to a specific weight of the fluid such that the coefficients approach the inversion point. Some measurements in the region of negative Joule-Thomson coefficient may be undertaken.
Economic Choice of Generator Unit Size
Authors: Kirchmayer L. K. , Mellor A. G.
Published: January 2022

This paper presents a method of analysis for the economic choice of generator unit size based on probability mathematics. The application of this method to a study of an assumed single integrated system is given as well as a study of two interconnected areas.
The Spiral Point Drill—A New Concept in Drill Point Geometry
Authors: Ernst Hans , Haggerty W. A.
Published: January 2022

The drilling process is one of the oldest and most widely used manufacturing operations. Billions of holes are drilled each year, and over 100 million drills are manufactured annually in the United States alone. However, in spite of its economic importance, the geometrical shape of the drill point (the so-called “chisel edge”) has remained virtually unchanged for over a hundred years, even though its disadvantages of lack of centering, and poor cutting action at the center, have long been recognized.

This paper describes an investigation into the cause of these disadvantages and a search for other geometrical forms which might result in improved performance. In the course of this investigation a “three-dimensional spiral” point shape was devised with interesting technical and performance characteristics, together with a unique method of point generation.

Photomicrographs are presented showing sections through the drill point and partly formed chips at various points along the cutting edge, both for the conventional chisel point and the spiral point shapes, showing characteristic differences in chip formation. The results of a series of investigations of cutting forces and other performance criteria such as roundness, hole size, and drill life, are presented for both of these shapes, together with a few case histories of results obtained with the new geometry under repetitive manufacturing conditions. A description is given of a method for producing this shape on any type of drill.

A modified form of the basic spiral point geometry is shown, which has additional unique characteristics for the drilling of sheet metal, and which therefore may have important applications in the aircraft and other sheet-metal fabricating industries.
Behavior of Cutting Fluids in Reaming Steels
Authors: Colwell L. V. , Branders Henrik
Published: January 2022

This investigation reveals that there can be considerable rubbing on the margins of reamers. This condition is intensified with more effective lubricants. Torque requirements increase, hole size and surface roughness decrease with increase in lubricant effectiveness.