bluuebunny/crossref_metadata_2025 huggingface dataset:
Identifying contemporary early retirement factors and strategies to encourage and enable longer working lives: A scoping review
Authors: Wilson Donna M. , Errasti‐Ibarrondo Begoña , Low Gail , O'Reilly Pauline , Murphy Fiona , Fahy Anne , Murphy Jill
Published: March 2020

Aim

Accelerating population ageing is raising concern in many countries now in relation to the availability of workers for essential work roles and responsibilities. A scoping research literature review was done to identify factors currently associated with early retirement and contemporary strategies to encourage and support longer working lives.

Methods

Using the PRISMA‐ScR Checklist, we searched the Directory of Open Access Journals and EBSCO Discovery Service for published 2013–2018 research articles using the keyword/MeSH term “early retirement”; 54 English‐language articles in peer‐review journals were reviewed.

Results

Seven early retirement factors were revealed: Ill health, good health, workplace issues, the work itself, ageism, social norms and having achieved personal financial or pension requirement criteria. Six suggested solutions, none proven effective, were identified: Occupational health programmes, workplace enhancements, work adjustments, addressing ageism, changing social norms and pension changes.

Conclusions

The evidence base on early retirement prevention is not strong, with qualitative investigations needed for in‐depth understandings of early retirement influences and mixed‐methods studies needed to test early retirement prevention solutions for their effects.

Implications for practice

Until more evidence is available, every organisation should perform an early retirement risk assessment and identify current versus needed policies and programmes to encourage and enable more middle‐aged and older people to work longer.
Correlation between an ABO Blood Group and Primary Femoral Head Necrosis: A Case–Control Study
Authors: Yang Shu‐Yan , Zeng Ling‐Yuan , Li Chao , Yan Hong
Published: March 2020

Objective

To investigate the relationship between primary femoral head necrosis (ONFH) and an ABO blood group.

Methods

This study was a retrospective case–control trial. An analysis of the clinical data of an ABO blood group with 516 patients (case group) with ONFH and 489 limb‐fracture patients (control group) without previous hip pain was obtained from the Second Hospital of Shanxi Medical University from November 2015 to November 2018. The clinical data included gender, age, height, weight, a history of smoking, alcohol abuse, prior medical history, hormone use, and ABO blood type. A logistic regression model was used for univariate and multivariate analysis.

Results

From November 2015 to November 2018, there were 267 males and 249 females in the 516 cases of ONFH in the case group. The control group included 289 males and 200 females. In terms of age, the average age of the case group was significantly lower than that of the control group. In terms of body mass index (BMI), the BMI of the case group was significantly higher than that of the control group (P < 0.05). From the previous medical history of patients in the two groups (coronary heart disease, hypertension, cerebrovascular disease, diabetes, and peripheral vascular disease), there was no significant difference between the two groups from a statistical perspective (P < 0.05). However, according to the risk factors of ONFH (smoking, alcohol abuse, hyperlipidemia, and hormone‐use history), there were significant differences between the case group and the control group. There was no statistical difference in the quantitative distribution ratio of the four blood types – A, B, O, and AB – between the case group and the control group. The outcomes of logistic multiple regression analysis presented that there was no significant correlation between the occurrence of ONFH and blood type A, B, AB, and O (P > 0.05). However, there are significant differences in the disease progression between the different blood types. There was a significant difference in the progression of disease between type A and type O. Among them, patients with ONFH and type A blood had the fastest progression with an average of 2.318 years, and the slowest progression was found in type O blood with an average of 5.15 years.

Conclusions

The ABO blood group has no correlation with the occurrence of ONFH, but the ABO blood type is closely related to the disease progression of ONFH.
Diaphragmatic hernias after pediatric liver transplantation: Experience of a high‐volume transplant center
Authors: Karakas Serdar , Sahin Tevfik Tolga , Kutluturk Koray , Otan Emrah , Baskiran Adil , Sarici Kemal Baris , Varol Ilknur , Aydin Cemalettin , Kayaalp Cuneyt , Yilmaz Sezai
Published: March 2020

Diaphragmatic hernias (DHs) are rare complications after pediatric liver transplantation (PLT). It is now widely accepted that DHs after liver transplantation (LT) is a pediatric related condition. PLTs (under of age 18) performed between January 2013 and June 2019 at Malatya Inonu University Institute of Liver Transplantation were retrospectively scanned. Study group consisting DHs and a control group were compared. Among 280 PLTs, 8 of them were complicated with DHs (%2.9). Median age of the patients with DH was 3.0 (0.8‐9.5) years. Median graft recipient weight ratio was 2.5 (0.9‐4.4). Five patients were below 5th percentiles in terms of pediatric weight growth chart at the time of LT. Also, 6 patients were below 5th percentiles in terms of pediatric height growth chart. There was no statistical difference between study and control groups. There are many risk factors mentioned in literature that may be primarily responsible for DHs after PLT. These factors are left lobe and large‐for‐size grafts, malnutrition, trauma or diathermy of diaphragmatic nerve and vessels and immunosuppressants. In our study, we could not specify any reason that differs in DHs. In our aspect, narrow diaphragma and thorax are exposed to high intra‐abdominal pressure from abdomen. Large‐for‐size grafts, which are specific to children, also may contribute to this affect. Excessive diathermy and trauma to diaphragmatic collaterals may aggravate the risk of DH. More patients are needed to make an exact conclusion, in order to evaluate with comparable study on this aspect.
Successful liver transplantation in short telomere syndromes without bone marrow failure due to DKC1 mutation
Authors: del Brío Castillo Rodrigo , Bleesing Jacob , McCormick Thomas , Squires James E. , Mazariegos George V. , Squires Judy , McKiernan Patrick J.
Published: March 2020

Short telomere syndromes are a heterogenous spectrum of disorders leading to premature cellular aging. These may involve bone marrow failure, adult‐onset idiopathic pulmonary fibrosis, and liver disease, and classical entities such as dyskeratosis congenita. We report a patient who presented with common variable immunodeficiency at 3 years of age and autoimmune cytopenias at 8 years of age. He was found to have short telomeres, and genetic testing confirmed a hemizygous mutation NM_001363.4: c.‐142C > G in DKC1 gene. He subsequently developed cirrhosis with severe portal hypertension and hepatopulmonary syndrome, prompting liver transplantation at 11 years of age. He remains well 10 years after transplant with no progression of bone marrow failure or progressive lung disease. In conclusion, short telomere syndromes should be considered as a potential cause of pediatric liver disease of unknown etiology, and in severe cases, isolated liver transplantation may be both appropriate and successful.
Pathophysiology of atherothrombosis: Mechanisms of thrombus formation on disrupted atherosclerotic plaques
Authors: Asada Yujiro , Yamashita Atsushi , Sato Yuichiro , Hatakeyama Kinta
Published: March 2020

Atherothrombosis is a leading cause of cardiovascular mortality and morbidity worldwide. The underlying mechanisms of atherothrombosis comprise plaque disruption and subsequent thrombus formation. Arterial thrombi are thought to mainly comprise aggregated platelets as a result of high blood velocity. However, thrombi that develop on disrupted plaques comprise not only aggregated platelets, but also large amounts of fibrin, because plaques contain large amount of tissue factor that activate the coagulation cascade. Since not all thrombi grow large enough to occlude the vascular lumen, the propagation of thrombi is also critical in the onset of adverse vascular events. Various factors such as vascular wall thrombogenicity, local hemorheology, systemic thrombogenicity and fibrinolytic activity modulate thrombus formation and propagation. Although the activation mechanisms of platelets and the coagulation cascade have been intensively investigated, the underlying mechanisms of occlusive thrombus formation on disrupted plaques remain obscure. Pathological findings derived from humans and animal models of human atherothrombosis have uncovered pathophysiological processes during thrombus formation and propagation after plaque disruption, and novel factors have been identified that modulate the activation of platelets and the coagulation cascade. These findings have also provided insights into the development of novel drugs for atherothrombosis.
To Thine Own Self Be True: Asymmetric Information in Procurement Auctions
Authors: Wooten Joel O. , Donohue Joan M. , Fry Timothy D. , Whitcomb Kathleen M.
Published: March 2020

As procurement auctions increasingly move to digital platforms, more data and information is available (or can be made available) to bidders. Despite this trend, relatively little is known about the impact of information asymmetries in these settings. We investigate two such differences in first‐price sealed‐bid reverse auctions with a common value. In a design that mirrors real construction procurement auctions, our laboratory experiment tests the impact of the precision of a bidder's cost estimate and the degree to which bidders know the inherent cost estimate precisions in the auction. We find that more understanding of estimate precision decreases bidder profit, counter to our expectation; however, we also find evidence of strategic behavior from those bidders that ratchets up pressure on competitors and pushes competitors toward bankruptcy. Most notably, understanding just one's own precision can help avoid the winner's curse in some settings. The same result does not apply if bidders also know their competitor's precision; more information does not help. The implication from our realistic setting—that reduced uncertainty may not help the bidder—raises important questions about the degree of transparency that is optimal in procurement auctions.
Sustainable Electric Vehicle Charging using Adaptive Pricing
Authors: Valogianni Konstantina , Ketter Wolfgang , Collins John , Zhdanov Dmitry
Published: March 2020

A transition to electric vehicles (EVs) is widely assumed to be an important step along the road to environmental sustainability. However, large‐scale adoption of EVs may put electricity grids under critical strain, since peaks in electricity demand are likely to increase radically. Efforts to manage demand peaks through pricing schemes may create new peaks at low‐price periods, if large numbers of EV owners use smart charging to benefit from low prices. This effect is expected to be amplified when EV owners adopt smart decision support to assist them with optimal charging decisions. Therefore, energy policymakers are interested in advanced pricing schemes that can smooth demand or induce demand that comes as close as possible to a desired profile. We show, through simulations calibrated with real‐world data, that current approaches to electricity pricing are limited in their ability to induce desired demand profiles. To address this challenge, we present adaptive pricing, a method to learn from EV owner reactions to prices and adjust announced prices accordingly. Our method draws on the Green Information Systems principles and can assist grid operators in ensuring the reliable operation of the grid. We evaluate our results in simulations, where we find that adaptive pricing outperforms current electricity pricing schemes, yielding results close to the theoretically optimal ones. We test our method in inducing both flat and extremely volatile demand profiles, and we see that in both cases it manages to induce EV charging close to the ideal scenario under perfect information.
The neurophysiological correlates of the triarchic model of psychopathy: An approach to the basic mechanisms of threat conditioning and inhibitory control
Authors: Paiva Tiago O. , Almeida Pedro R. , Coelho Rui C. , Pasion Rita , Barbosa Fernando , Ferreira‐Santos Fernando , Bastos‐Leite António J. , Marques‐Teixeira João
Published: March 2020

The psychopathic traits boldness, meanness, and disinhibition are theorized to be underlined by trait fearlessness and externalizing vulnerability as etiologic neurobiological processes. However, little is known about the neurophysiological correlates of these traits. In this work, we explored how the three traits are associated with event‐related potential (ERP) components targeted at the etiological processes in a partial delayed threat conditioning task and in a go/no‐go task. Fifty community‐dwelling volunteers (25 women), without history of neurological or psychiatric conditions, were recruited and assessed for psychopathic traits using the triarchic psychopathy measure. Participants performed a threat conditioning task, and a go/no‐go task while undergoing an electroencephalography recording. Results from the threat conditioning task showed that boldness was significantly associated with reduced late positive potential. Concerning the go/no‐go task, disinhibition was significantly associated with reduced error‐related negativity ERP component. Overall, distinct psychopathic traits were found to be associated with distinct neurophysiological correlates of threat conditioning and response inhibition. This is consistent with models of psychopathy entailing trait fearlessness and externalizing proneness, and related brain mechanisms, as distinct processes underlying the expression of psychopathic traits.
Soil and geologic formations as antidotes for CO2 sequestration?
Authors: Wang Lei , Sarkar Binoy , Sonne Christian , Ok Yong Sik , Tsang Daniel C. W.
Published: March 2020

Rapid and far‐reaching transitions are required to combat climate change and its impacts. Carbon capture and storage within mineral deposits is a promising solution to remove CO2 from the atmosphere. In‐situ geological storage and ex‐situ mineral sequestration are practically sufficient for sequestering all the anthropogenic CO2. Recent research reports that more than 95% of injected CO2 was mineralized into carbonates in two years by using in‐situ geological approach, and mining wastes and secondary minerals were recycled as resources for ex‐situ CO2 sequestration. However, geological activity is the major risk of in‐situ storage, while high energy consumption and associated cost may limit the application of ex‐situ carbonation. Significant technical breakthroughs of mineral and geological CO2 sequestration are therefore of vital importance to realize a “net‐zero CO2 emissions” and even “carbon‐negative” society.
The HLA‐DRB1*04:05:21 allele identified in a volunteer donor for hematopoietic stem cell transplant
Authors: Baek In‐Cheol , Choi Eun‐Jeong , Shin Dong‐Hwan , Kim Hyoung‐Jae , Kim Tai‐Gyu
Published: March 2020

HLA‐DRB1*04:05:21 differs from HLA‐DRB1*04:05:01:01 in codon 83 in exon 2.
Tile‐based polygon overlay of vector data in a virtual globe
Authors: Zhou Mengyun , Wang Lizhe , Chen Xiaoyu , Wu Si , Li Huawei
Published: March 2020

The demand for analysis of large‐scale data has increased with increased access to spatial vector data. Polygon overlay of vector data in a virtual globe requires proprietary data structures and proprietary analysis algorithms. A vector data structure is designed for rapid polygon overlay in a virtual globe by recording the metadata of the triangles (TriMeta) that constitute polygons. A polygon overlay algorithm is proposed based on this data structure. The overlay of two complex GIS polygons is transformed into the intersection computation of their 3D triangular presentations. The intersection computation of two sets of triangles is reduced considerably by utilizing TriMeta to filter out the disjoint triangle pairs and rapidly identify the contained triangle. The new method improves the overlay efficiency in a virtual globe because the amount of computation required to calculate the intersections of two large polygons and drape the intersections onto a terrain surface is reduced.
Structure and function of LCI1: a plasma membrane CO2 channel in the Chlamydomonas CO2 concentrating mechanism
Authors: Kono Alfredo , Chou Tsung‐Han , Radhakrishnan Abhijith , Bolla Jani Reddy , Sankar Kannan , Shome Sayane , Su Chih‐Chia , Jernigan Robert L. , Robinson Carol V. , Yu Edward W. , Spalding Martin H.
Published: March 2020

Microalgae and cyanobacteria contribute roughly half of the global photosynthetic carbon assimilation. Faced with limited access to CO2 in aquatic environments, which can vary daily or hourly, these microorganisms have evolved use of an efficient CO2 concentrating mechanism (CCM) to accumulate high internal concentrations of inorganic carbon (Ci) to maintain photosynthetic performance. For eukaryotic algae, a combination of molecular, genetic and physiological studies using the model organism Chlamydomonas reinhardtii, have revealed the function and molecular characteristics of many CCM components, including active Ci uptake systems. Fundamental to eukaryotic Ci uptake systems are Ci transporters/channels located in membranes of various cell compartments, which together facilitate the movement of Ci from the environment into the chloroplast, where primary CO2 assimilation occurs. Two putative plasma membrane Ci transporters, HLA3 and LCI1, are reportedly involved in active Ci uptake. Based on previous studies, HLA3 clearly plays a meaningful role in HCO3− transport, but the function of LCI1 has not yet been thoroughly investigated so remains somewhat obscure. Here we report a crystal structure of the full‐length LCI1 membrane protein to reveal LCI1 structural characteristics, as well as in vivo physiological studies in an LCI1 loss‐of‐function mutant to reveal the Ci species preference for LCI1. Together, these new studies demonstrate LCI1 plays an important role in active CO2 uptake and that LCI1 likely functions as a plasma membrane CO2 channel, possibly a gated channel.
Analysis of transfusion therapy during the March 2019 mass shooting incident in Christchurch, New Zealand
Authors: Badami Krishna G. , Mercer Susan , Chiu May , Yi Ma , Warrington Sue
Published: March 2020

Background and objective

A mass casualty incident occurred in Christchurch in March 2019. Thirty‐seven patients with gunshot wounds were admitted. We describe and analyse the transfusion management of these casualties.

Methods

Data on demographics, injury and laboratory characteristics, and transfusions are summarized using descriptive statistics. Relationships between variables are examined using Pearson's and Spearman's rank correlations. Univariate analysis of explanatory variables is performed to determine the best early predictors of transfusion requirements. The characteristics of massive transfusion and non‐massive transfusion cases are compared using the t‐ and Mann–Whitney tests.

Results

Sixty‐five per cent received transfusions. Initial Hb, platelet counts and clotting results were mostly normal. On average, each gunshot wound patient was transfused 4, 3·1, 1·2 and 0·4 units of RBC, FFP, cryoprecipitate and platelets, respectively, on the day. Base excess was the single best predictor of transfusion requirements.

Conclusions

A greater proportion of those with gunshot wounds in this incident were transfused than in other such incidents. Transfusion requirements for patients varied but were generally modest. Blood component transfusion ratios were close to that recommended. The role of base excess as a predictor of transfusion requirements in patients with similar injuries needs more study.
Design and Numerical Analysis of an Electrostatic Energy Harvester With Impact for Frequency Up-Conversion
Authors: Lensvelt R. , Fey R. H. B. , Mestrom R. M. C. , Nijmeijer H.
Published: March 2020

Integration of vibration energy harvesters (VEHs) with small-scale electronic devices may form an attractive alternative for relatively large batteries and can, potentially, increase their lifespan. However, the inherent mismatch between a harvester's high-frequency resonance, typically in the range 100−1000 Hz, relative to the available low-frequency ambient vibrations, typically in the range 10–100 Hz, means that low-frequency power generation in microscale VEHs remains a persistent challenge. In this work, we model a novel electret-based, electrostatic energy harvester (EEH) design. In this design, we combine an out-of-plane gap-closing comb (OPGC) configuration for the low-frequency oscillator with an in-plane overlap comb configuration for the high-frequency oscillator and employ impact for frequency up-conversion. An important design feature is the tunability of the resonance frequency through the electrostatic nonlinearity of the low-frequency oscillator. Impulsive normal forces due to impact are included in numerical simulation of the EEH through Moreau's time-stepping scheme which has, to the best of our knowledge, not been used before in VEH design and analysis. The original scheme is extended with time-step adjustments around impact events to reduce computational time. Using frequency sweeps, we numerically investigate power generation under harmonic, ambient vibrations. Results show improved low-frequency power generation in this EEH compared to a reference EEH. The EEH design shows peak power generation improvement of up to a relative factor 3.2 at low frequencies due to the occurrence of superharmonic resonances.
The Effects of Asymmetric Slip Flow Between Parallel Plates of a Microchannel Under Uniform Heat Flux
Authors: Ahmadi Nadooshan Afshin , Jahanbakhshi Akram , Bayareh Morteza
Published: March 2020

Microchannels have many applications in the field of modern technologies. Today, it is necessary to increase the efficiency of these systems due to the increasing rate of thermal loads. Recent researches have shown that liquid flows in the microchannels depend on their size and surface properties. Consequently, there is no symmetric flow condition in a symmetric geometric channel necessarily. In this study, the effect of slip length on the amount of asymmetric heat transfer in a microchannel is investigated numerically. By calculating the parameters such as Nusselt number and local pressure drop coefficient, it is observed that the asymmetric slip flow affects the flow profile and could lead to a decrease or increase in the heat transfer in the microchannel. According to the results, asymmetric slip flow can lead to a 20–40% reduction or increase in the Nusselt number. The most important point in the design of micro-scale asymmetric cooling systems is the increase of slip length at high temperatures.
Analytically Predicating the Multi-Dimensional Accuracy of the Honed Engine Cylinder Bore
Authors: Zhang Xueping , Zhou Zaoyang , Yao Zhenqiang , Xi Lifeng
Published: March 2020

The dimensional accuracy of engine cylinder bore at multiscale has a tremendous influence on engine performances including friction power loss, vibration, leak tightness between piston and cylinder, and wear resistance. Tremendous researches were devoted to predict the dimensional accuracies of the honed cylinder by means of analytical, experimental, and numerical simulation methods. The dimensional quality of the honed cylinder bore was usually determined by establishing the relationship between honing parameters and dimensional accuracies of the honed cylinder bore. However, most researches predicted dimensional accuracy at macroscale or surface texture at microscale, respectively. Few efforts were devoted to predict the dimensional quality of honed cylinder bore at both macroscale and microscale levels simultaneously. To explore a new understanding of the honing mechanism of the cylinder bore, a multiscale model is proposed to predict the dimensional accuracy and surface texture of cylinder bore generated from the honing process at the macroscale and microscale simultaneously. The model aims to integrate both microscale factors including honing stone abrasives distribution, abrasive wear process, previous cylinder surface topography, and macroscale factors including cylinder geometric features and honing head motion trajectory into a multiscale analytical analysis. A force matching method is adopted in the multiscale predictive model to determine the feed depth in the honing of the cylinder bore. Thus, the proposed multiscale analytical model possesses an excellent capacity to simultaneously predict the roundness and cylindricity of the honed cylinder bore, as well as the surface texture/roughness of the honed cylinder bore in terms of Abbott-Firestone curve. The simulated results also revealed that the material removal process is closely related to the initial shape deviations of the cylinder bore, which cannot be corrected, compensated, or eliminated by the subsequent honing process given the deviations are associated with wavelengths higher than 27 mm under the given honing condition.
Combined Supercharging System: The Best Fit for Submarine Engines
Authors: Herrmann R.
Published: March 2020

The two types of supercharging processes, either with turbocharger or with mechanically driven compressor are the two systems known to be used on diesel engines for submarines. Each of these two systems has its own limitations.

A two stage supercharging system has been investigated and developed by S.E.M.T. Pielstick. This system is based on a turbocharger used as a low-pressure stage combined with a high-pressure stage compressor which is mechanically driven by the engine.

Test bench results are compared with those obtained with the classical systems.

The new system with two-stage compression has an advantage particularly for the following main points:

- specific power,

- air and fuel specific consumptions,

- capability to sustain high exhaust back pressures as well as low suction pressures and low sensitivity to their fluctuations,

- safety against engine stalling in case of loss of submersion control.
Diesel Engine Development for Low Emission Rail Traction Application
Authors: Karimi E. R. , Orrell A. G.
Published: March 2020

This paper describes the evolution of a family of modern four stroke high power density engines, the Ruston RK215 series, which has been developed to meet the specific needs of heavy duty rail traction application including the current EPA and UIC (European) emissions legislation. It discusses the extensive experience of Ruston in powering various locomotives including recent applications in overseas markets.

The methodology adopted in the base engine design, to achieve high reliability and good component life is discussed with methods of validation and risk analysis during the design and development program. Specific reference is made to an emissions research program to ensure the engine will comply fully with future legislation.
Performance and Exhaust Emissions of a Diesel Engine Running With DME
Authors: Maroteaux F. , Descombes G. , Sauton F.
Published: March 2020

This research investigates engine performance and the potential of reducing exhaust emissions by using Dimethyl Ether (DME) which is an alternative fuel for diesel engines. The objective of this study it to evaluate (on the bed test) the performance and emissions reduction potential of an engine running with DME. A 4 cylinder passenger car HSDI Common Rail turbocharged diesel engine without specific modifications was used.

The results obtained on this engine running with DME using diesel fuel as reference are encouraging. In the next steps of this study the injection rate will be adapted to DME operation and to the geometric and thermodynamic conditions of the combustion reaction. A study of the combustion reaction is also necessary in order to optimize the turbocharging system to exclusive DME operation.
The GE/Jenbacher 1 MW Dual Speed Gas Engine Concept for the GE Rental Fleet
Authors: Kabel Dan , Gruber F. , Wagner M. , Herdin G. R. , Meßner E. , Hilscher H.
Published: March 2020

Jenbacher AG (JAG) has designed with General Electric (GE) a new container-based gas engine gen-set package for the GE rental fleet. All necessary system components like the natural gas engine, alternator, cooling fans, electrical units and auxiliaries are integrated in one 40-foot ISO container which is normally placed on a trailer truck. A unit weight of less than 53,000 lbs ensures easy transport from site to site. The gas and electricity connections are designed to ensure the lowest possible installation and setup times. The application of a closed loop cooling system inside the container has the advantage that no additional connections are necessary. Connections for heat recovery are integrated, and can easily be utilized if there is a demand. Another important feature is that the gen set is not influenced to a great extent by changes in environmental conditions. Ambient temperatures of up to 104°F (40°C) are still permissible without reduction of power output. Container insulation and exhaust gas silencer design are optimized to attain a noise level of 74 dB(A) at a distance of 7 m.
A Non-Equilibrium Turbulence Dissipation Correction and its Influence on Pollution Predictions for DI Diesel Engines
Authors: Tanner Franz X. , Zhu Guang-Sheng , Reitz Rolf D.
Published: March 2020

A correction for the turbulence dissipation rate, based on non-equilibrium turbulence considerations from rapid distortion theory, has been derived and implemented in combination with the RNG k–ε model in a KIVA-based code. This correction reflects the time delay between changes in the turbulent kinetic energy due to changes in the mean flow and its turbulence dissipation rate, and it is shown that this time delay is controlled by the turbulence Reynolds number. The model correction has been validated with experimental data in the compression and expansion phase of a small diesel engine operated in motored mode. Combustion simulations of two heavy-duty DI diesel engines have been performed with the RNG k–ε model and the dissipation rate correction. The focus of these computations has been on the nitric oxide formation and the net soot production. These simulations have been compared with experimental data and their behavior is explained in terms of the turbulence dissipation effect on the transport coefficients for mass and heat diffusion. It has been found, that the dissipation correction yields consistent results with observations reported in previous studies.
Multidimensional Modeling of Premixed Turbulent Combustion: Modeling and Testing of a Small Spark-Ignition Engine
Authors: Fontana Gustavo , Galloni Enzo , Jannelli Elio
Published: March 2020

Combustion models, used in spark-ignition engine modeling, are reviewed. Different approaches for representing the main combustion features are reported. Limitations in simulating such a complex phenomenon as turbulent combustion in engines are highlighted as well.

In order to compare different combustion models, the multidimensional program KIVA-3V has been used. The behavior of an actual spark-ignition engine has been investigated.

In particular, simulation results, using simple chemical kinetics and mixing-controlled models, are compared. The results obtained, compared to measured data, confirm that different combustion models can lead to a satisfactory prediction of engine performances. But, in many cases, these models require experimental data for determining the model characteristic constants. A hybrid combustion model is proposed. It is able to provide a good reproduction of engine combustion process and, in particular, the model seems to be less sensitive to the engine operation. The computation results are compared to the measured data.
Experimental and Theoretical Optimization of Combustion Chamber and Fuel Distribution for the Low Emission DI Diesel Engine
Authors: Kidoguchi Yoshiyuki , Sanda Michiko , Miwa Kei
Published: March 2020

This study investigated the effect of combustion chamber geometry and initial mixture distribution on combustion process in a direct-injection diesel engine by means of experiment and CFD calculation. The high squish combustion chamber with squish lip could produce simultaneous reduction of NOx and particulate emissions with retarded injection timing in the real engine experiment. According to the CFD computation, the high squish combustion chamber with central pip is effective to continue combustion under the squish lip until the end of combustion and the combustion region forms rich and high turbulence atmosphere, which reduces NOx emissions. This chamber can also reduce initial burning because combustion continues under the squish lip. The CFD computation is also carried out in order to investigate the effect of initial mixture distribution on combustion process. The results suggest that mixture distribution affects the history of heat release rate. When fuel is distributed in the bottom or wide region in the combustion chamber, burned gas tends to spread to the cavity center and initial heat release rate becomes high. On the contrary, the high squish combustion chamber with central pip produces lower initial heat release rate because combustion with local rich condition continues long under the squish lip. Diffusion burning is promoted by high swirl motion in this chamber with keeping lower initial heat release rate.
The Description of a Combined Thermodynamic Power System Using a Two-Phase Fluid and Air As Working Fluids
Authors: Jirnov Alexei A. , Borissov Anatoli , McCoy James J.
Published: March 2020

A combined thermodynamic power system is described that uses a two-phase fluid (air and water) to form the basis of a cycle that employs the isothermal compression of the working fluid to improve the overall efficiency. The compressor and the expander described in the system utilize sliding-blade rotary devices that together make up an air-heat engine that operates on a modified Brayton cycle. Key to this device is the utilization of an isothermal compression of the air and the efficient use of waste heat in a regenerative process to achieve high thermal efficiency and reduce environmentally damaging emissions. In addition, a special pre-chamber/vortex combustion chamber allows for the introduction of heat in an environmentally friendly manner.
Numerical Prediction to Effects of Manifolds Configuration on Flow in Swirling Flow Exhaust Pipe System
Authors: Cao L. , Liu Huimeng , Liu Yongchang , Huang Q.
Published: March 2020

Compared to conventional Modular Pulse Converter (MPC) system with the typical structure of symmetrical T-junction, a novel swirling flow exhaust pipe system has its advantages especially in reducing collision loss of high-speed gases near junction and having interference-free scavenging and higher energy utilization. The initial junction configuration in swirling flow exhaust system was determined with reference to T-junction in MPC. In order to analyze and compare its flow behaviors, 3D-flow fields of manifold-type junctions in swirling flow exhaust pipe system were performed with the revised KIVA II code. A non-linear algebraic Relynolds stress (ASM) model was considered in this study and comparisons were made with the standard κ–ε turbulence model. For many cases of parametric studies considered, it is found that junction’s configurations have significant influence on the velocity distribution and swirl intensity. 30° swirling flow junction is found to be unreasonable, 45° junction with oblate rectangular type contraction area is recommended in swirl flow pipe exhaust pipe system.

3D-Particle Dynamic Analyzer (PDA) measurement was introduced to measure the axial and tangential velocity components of swirling flow in main pipe. Comparisons of computed and measured velocities reveal that model predictions are in generally reasonable agreement with the measurements, indicating validity of computational code and reliability of prediction model.
The Future of Magnetic Recording
Authors: Wood Roger
Published: March 2020

Magnetic information storage technology has made astounding progress since its invention over a hundred years ago. For the last several years, storage packing densities in hard disk drives have doubled every year! This frantic pace is expected to soon slow because of the some very fundamental limits that are becoming increasingly evident in the technology. Conventional magnetic recording technology is expected to ultimately reach densities of several hundred Gigabits per square inch and data-rates of a few Gigabits/s (current products are ∼25 Gbit/sq.in. and over 0.5 Gbit/s). We examine the key limiting factors and then try to develop a consistent geometry and set of material properties that could support a density close to one Terabit per square inch. Finally we speculate about the external characteristics of a small hard disk drive that would store one Terabyte of information [1].
A New Finite-Element Based Suspension Model Including Displacement Limiters for Load/Unload Simulations
Authors: Weissner Stefan , Zander Uwe , Talke Frank E.
Published: March 2020

A new beam suspension model for load/unload simulations of magnetic hard disk drive sliders is presented. The model is applicable to the load/unload process as well as to the dynamic flying behavior of the slider on the disk. Suspension and gimbal are modeled with C1 continuous beam elements. The roll degree of freedom of the slider is decoupled from spacing and pitch. The numerical implementation of the model is described. Loading and unloading of a typical subambient pressure type slider is presented.
Self-Adjusting Flying Height Sliders for Operation in the Near-Contact Recording Regime
Authors: Hanchi J. , Serpe C. I. , Qian W. , Boutaghou Z.
Published: March 2020

The viability of the concept of “self-adjusting flying height” for giant magneto-resistive (GMR) recording heads designed for operation in the near-contact recording regime (flying heights below 10 nm) is demonstrated experimentally. In the present context, the realization of the latter concept relies upon the micro-texturing — production of deterministic, spatially coherent surface topography patterns — of potential contact regions on the recording heads. Through the manipulation of micro-texture pattern feature geometry and spatial distribution, the apparent area of contact, or bearing area ratio, in such regions can be varied in a controllable manner. The latter affords a means to enable the transition of head-disc interfaces (HDI) initially operating under interference contact conditions, into the fly regime without impairing the mechanical and electrical integrity of the HDI. Experimental results attesting to the feasibility of the concept self-adjusting flying height for GMR heads are presented and discussed. Practical aspects associated with the implementation of the latter concept are also discussed.
Head-Disk Interface Issues for Near Contact Recording
Authors: Wang R. H. , Raman V. , Nayak U. V.
Published: March 2020

As the magnetic recording density increases towards hundreds of Gb/in2, both the magnetic spacing and head-disk clearance decrease to < 10 nm. By one estimate, the magnetic spacing for 1 Tb/in2 is about 6 nm and the read width is ∼ 30 nm. There are at least two different approaches to achieving this. The first one is an extension of the traditional flying interface and the second is contact recording. In the former case one needs to be concerned about maintaining adequate clearance both at sea level and at higher elevation whereas in the latter case the wear and corrosion of the heads and disks may pose major challenges.

In the flying regime, an accelerated test to assess the relative integrity of the head-disk interface is described here. This is accomplished by monitoring the acoustic emission, capacitance or friction between the head and the disk as the ambient pressure is reduced. The pressure at which an abrupt change in the above signals takes place is called take-off pressure (TOP). This is also known as altitude avalanche measurement. With this method it is possible to compare different disk and head designs at the full velocity of the slider. We present results correlating the TOP with disk roughness and the influence of disk lubricant.

An example of how head-disk interference takes place in a disk drive will be given for an experimental 10 nm flying slider. The effects of radial flying height profile, take-off height of the disk, and the disk curvature on mechanical spacing are presented. The results of changes occurring on the air bearing surface and the disks after long term flyability test are discussed.
“We Took Pictures”: Children’s Meaning-Making in Physical Education
Authors: Ní Chróinín Déirdre , Coulter Maura , Parker Melissa
Published: March 2020

Purpose: Studying learning in primary physical education is complex and largely practical and embodied; not only involving the child, but also closely linking the lesson context. The aim of this paper is to understand teaching and learning in primary physical education through the use of photo-diaries.Method: Participants were children (n = 38) and their teachers (n = 2)  from two Irish primary schools across a 6-week period. Data included children’s photo-diaries, photo-elicitation focus group interviews with the children, and interviews with their teachers.Results: Results highlight that photo-diaries supported children’s meaning-making processes about their learning, highlighting a variety of meanings grounded in the centrality of the body as performance of learning.Discussion and Conclusion: The value of photo-based approaches with primary school children to access their meaning-making and influences on their understandings is highlighted.
Multistage and passive cooling process driven by salinity difference
Authors: Alberghini Matteo , Morciano Matteo , Fasano Matteo , Bertiglia Fabio , Fernicola Vito , Asinari Pietro , Chiavazzo Eliodoro
Published: March 2020

Net cooling flux and temperature difference shown in a static machine only driven by salty water solutions.
In situ recruitment of regulatory T cells promotes donor-specific tolerance in vascularized composite allotransplantation
Authors: Fisher James D. , Zhang Wensheng , Balmert Stephen C. , Aral Ali M. , Acharya Abhinav P. , Kulahci Yalcin , Li Jingjing , Turnquist Heth R. , Thomson Angus W. , Solari Mario G. , Gorantla Vijay S. , Little Steven R.
Published: March 2020

CCL22-releasing microparticles recruit suppressive immune cells to transplanted rat limbs to promote long-term graft survival.
Machine-knitted washable sensor array textile for precise epidermal physiological signal monitoring
Authors: Fan Wenjing , He Qiang , Meng Keyu , Tan Xulong , Zhou Zhihao , Zhang Gaoqiang , Yang Jin , Wang Zhong Lin
Published: March 2020

A triboelectric all-textile sensor with high pressure sensitivity and comfort was been developed for health monitoring.
Single-cell mass cytometry reveals cross-talk between inflammation-dampening and inflammation-amplifying cells in osteoarthritic cartilage
Authors: Grandi Fiorella Carla , Baskar Reema , Smeriglio Piera , Murkherjee Shravani , Indelli Pier Francesco , Amanatullah Derek F. , Goodman Stuart , Chu Constance , Bendall Sean , Bhutani Nidhi
Published: March 2020

This study defines a single-cell proteomic atlas of human OA cartilage to reveal rare subpopulations that stratify patients.
Computationally aided, entropy-driven synthesis of highly efficient and durable multi-elemental alloy catalysts
Authors: Yao Yonggang , Liu Zhenyu , Xie Pengfei , Huang Zhennan , Li Tangyuan , Morris David , Finfrock Zou , Zhou Jihan , Jiao Miaolun , Gao Jinlong , Mao Yimin , Miao Jianwei , Zhang Peng , Shahbazian-Yassar Reza , Wang Chao , Wang Guofeng , Hu Liangbing
Published: March 2020

We developed a computationally aided alloy synthesis in the multi-element space toward highly efficient and durable catalysts.
Terahertz quantum sensing
Authors: Kutas Mirco , Haase Björn , Bickert Patricia , Riexinger Felix , Molter Daniel , von Freymann Georg
Published: March 2020

Quantum sensing enables the measurement of sample properties in the terahertz frequency range by detecting visible photons.
An Engineered Double Lipid II Binding Motifs-Containing Lantibiotic Displays Potent and Selective Antimicrobial Activity against Enterococcus faecium
Authors: Zhao Xinghong , Yin Zhongqiong , Breukink Eefjan , Moll Gert N. , Kuipers Oscar P.
Published: March 2020

Lipid II is an essential precursor for bacterial cell wall biosynthesis and thereby an important target for various antibiotics. Several lanthionine-containing peptide antibiotics target lipid II with lanthionine-stabilized lipid II binding motifs. Here, we used the biosynthesis system of the lantibiotic nisin to synthesize a two-lipid II binding motifs-containing lantibiotic, termed TL19, which contains the N-terminal lipid II binding motif of nisin and the distinct C-terminal lipid II binding motif of one peptide of the two-component haloduracin (i.
Temperature and Nutrient Levels Correspond with Lineage-Specific Microdiversification in the Ubiquitous and Abundant Freshwater Genus
Limnohabitans
Authors: Props Ruben , Denef Vincent J.
Published: March 2020

Limnohabitans
is an important bacterial taxonomic group for cycling carbon in freshwater ecosystems worldwide. Here, we examined the genomic diversity of different
Limnohabitans
lineages. We focused on the LimB lineage of this genus, which is globally distributed and often abundant, and its abundance has shown to be largely invariant to environmental change. Our data show that the LimB lineage is actually comprised of multiple cooccurring populations for which the composition and genomic characteristics are associated with variations in temperature and nutrient levels. The gene expression profiles of this lineage suggest the importance of chemotaxis and motility, traits that had not yet been associated with the
Limnohabitans
genus, in adapting to environmental conditions.
Ecological and Ontogenetic Components of Larval Lake Sturgeon Gut Microbiota Assembly, Successional Dynamics, and Ecological Evaluation of Neutral Community Processes
Authors: Abdul Razak Shairah , Scribner Kim T.
Published: March 2020

We quantified the effects of environment (diet and water sources) and host early ontogenetic development on the diversity of and compositional changes in gut microbial communities based on massively parallel sequencing of the 16S rRNA genes from the GI tracts of larval lake sturgeon (
Acipenser fulvescens
). The gut microbial community diversity declined and the community composition differed significantly among ontogenetic stages; however, only modest differences associated with dietary or water source treatments were documented. Selectivity associated with microbe-host GI tract interactions through early ontogenetic stages was evident. The results have implications for lake sturgeon and early larval ecology and survival in their natural habitat and for conservation and aquaculture production specifically, as well as applications of microbe-based management in teleost fish generally.
Evaluation of the Performance of the IMMY sona
Aspergillus
Galactomannan Lateral Flow Assay When Testing Serum To Aid in Diagnosis of Invasive Aspergillosis
Authors: White P. Lewis , Price Jessica S. , Posso Raquel , Cutlan-Vaughan Morgan , Vale Lorna , Backx Matthijs
Published: March 2020

Management of invasive aspergillosis has been improved by biomarker assays, but limited accessibility and batch testing limit the impact. Lateral flow assays (LFA) are a simple method for use outside specialist centers, provided performance is acceptable. The objective of this study was to determine the performance of the recently released IMMY sona
Aspergillus
LFA when testing serum samples. The study took the form of a retrospective, anonymous case/control study comprising 179 serum samples from 136 patients with invasive fungal disease, previously documented using recently revised internationally accepted definitions.