bluuebunny/crossref_metadata_2025 huggingface dataset:
Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy for the Quantitative Analysis of Deuterium in Plasma: Application to Total Body Water Determination in Humans and Other Animals
Authors: Ward Leigh C.
Published: February 2021

Conventional methods for measuring the concentration of deuterium in body fluids are by either isotope ratio mass spectrometry or Fourier transform infrared transmission (FT-IR) spectroscopy. The latter method is often preferred as it is less expensive and time consuming; however, having a lower sensitivity means a larger sample volume is required. This study investigated an alternative FT-IR spectroscopic method, attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR), which has the potential to provide shorter analysis times while requiring smaller sample volumes. Deuterium was assayed using ATR FT-IR in plasma in the concentration range 0.5 to 2.5 mg mL−1, typical of those observed in tracer dilution measurements of total body water. Minimal sample preparation was required and analysis time was substantially decreased compared to transmission FT-IR. Samples were analyzed with high precision (coefficient of variation (CV) < 0.5%). Precision of assay was maintained when assaying plasma volumes of only 10 µL . The application of the method to the determination of total body water in humans and animals (horses) was demonstrated. A rapid and simple method for the measurement of deuterium in plasma is described that only requires very small sample volumes, rendering the method suitable for use in pediatrics where blood sampling is required to be kept to a minimum.
Xi’s Post-pandemic Outlook on Asia: Between Guanxi and Mingyun Gongtongti
Authors: Panda Jagannath
Published: February 2021

China’s contest with the global community has entered a delicate phase post the COVID-19 period. While the COVID-19 pandemic has exposed the non-responsible act of China in tackling the virus to prevent its spread outside the country, the recent aggression of the Chinese leadership on land and maritime domains in Asia has revealed the long-term international objectives of China’s ambitious foreign policy under Xi Jinping. As China attempts to rebuild its global image and profile post the pandemic and, most importantly, to reorder its global governance approach, Beijing may like to revitalise its focus on its Guanxi (relationship or networks) and Mingyun Gongtongti or ‘the Community with a Shared Future for Humankind’ (CHSF). In other words, China’s approach to Asia may take a new turn without Beijing shying away from its original intentions of dictating the Asian order.
Dependence Structure Between Renminbi Movements and Volatility of Foreign Exchange Rate Returns
Authors: Lai Wing-Choong , Goh Kim-Leng
Published: February 2021

This article investigates the linkages of the movements in Renminbi (RMB) to volatility of exchange rate returns of other currencies before and after the yuan devaluation on 11 August 2015. A comparison between the onshore Chinese yuan (CNY) and the offshore Chinese yuan (CNH) is made. Standard regression methods underestimate the tail dependence between yuan and other exchange rate volatility, as financial data are non-normally distributed, especially when extreme event occurs. We apply Gumbel copulas to capture the presence of tail dependence between RMB returns and the volatility of exchange rate returns for 13 selected currencies, and found dependencies not revealed by the standard ARCH models. The tail dependence has increased after the RMB devaluation, suggesting that RMB depreciation is associated with higher downside risks in these currencies. This is most obvious in the currencies of Asian and ASEAN-5 countries that have strong trade and financial linkages with China. The dependence structure has shifted away from the dominance of onshore CNY rates before the devaluation to the growing importance of more volatile offshore CNH rates after the devaluation. Hence, any large depreciation in CNH will lead to a higher volatility in the other exchange rate returns, and the corresponding downside currency risks are higher than those of the CNY.
An Indian Town’s Entry into the Second World War: Holding Together the Congress Party and Training Chinese Soldiers in Wartime Raj
Authors: Yin Cao
Published: February 2021

During the Second World War, Ramgarh, a small town in northeast India, was the site of the 53rd Session of the Indian National Congress and the training centre for the Chinese Expeditionary Force. By uncovering the links between the two events and knitting them into the broader context of the Indian nationalist movement and China’s War of Resistance, this article tries to break down the hegemony of the Eurocentric national narratives of the history of the Second World War in India and China. In doing so, it provides an alternative way of writing an entangled history of India and China during the Second World War.
The Failure of Forgiveness of Sins and the Successful Healing: A Postcolonial Reading of Luke 5:17–26
Authors: Lee Wookyoung
Published: February 2021

This article examines the story of Luke 5:17–26, in which Jesus raised a paralyzed man to walk. Jesus failed to cure the paralyzed man when he initially declared forgiveness of sins; however, he subsequently treated him with orders to stand up and walk. This proves that Jesus rejected the commonly accepted view of the time that the sick are sinners. In addition, this proves that the paralyzed man was healed not because he was a sinner, but because Jesus had the ability to heal. In this way, Jesus the governed is mocking the rulers by imitating their ideology in a mocking way.
Simulation of variable speed wind turbines based on open-source solutions: Application to bachelor and master degrees
Authors: Fernández-Guillamón Ana , Molina-García Ángel
Published: February 2021

This paper describes variable speed wind turbine (Types 3 and 4, IEC 61400–27-1) simulations based on an open-source solution to be applied to Bachelor and Master Degrees. It is an attempt to improve the education quality of such sustainable energy by giving an open-source experimental environment for both undergraduate and graduate students. Indeed, among the renewable sources, wind energy is currently becoming essential in most power systems. The simulations include both one–mass and two–mass mechanical models, as well as pitch angle control. A general overview of the structure, control, and operation of the variable speed wind turbine is provided by these easy-to-use interactive virtual experiments. In addition, a comparison between commercial and open-source software packages is described and discussed in detail. Examples and extensive results are also included in the paper. The models are available in Scilab-Xcos file exchange for power system education and researcher communities.
Governance capacity and regulatory enforcement: street-level organizations in Beijing’s food safety reform
Authors: Yee Wai-Hang , Liu Peng
Published: February 2021

How street-level organizations enforce regulations carries important governance implications. Through reviewing the regulatory enforcement literature and categorizing it into three broad governance modes, this article discusses the individual and organizational capacity prerequisites for street-level organizations to enact the corresponding government–society relationship and improve governance outcomes. Through analyzing enforcement challenges faced by street-level officers in Beijing’s recent food safety reform, the article also identifies the essential capacities for street-level organizations to regulate under a legal-hierarchical governance mode. The article hopes to inspire further research to uncover specific governance capacity requirements for other administrative organizations under different governance modes.

Points for practitioners

Apart from policy effectiveness, government regulators should also sometimes pay attention to their impacts on governance. Despite frontline regulators’ discretion, street-level organizations may improve governance outcomes by devising and implementing regulatory enforcement programs and strategies in line with the governance mode the government is engaged in as what they do enacts the specific government–society relationship in the governing process. Administrators in charge of street-level organizations may benefit from cultivating capacities essential to actualizing the respective governance mode. Absence of these capacities is likely to undermine governance effectiveness.
Breathing with Both Lungs: The Uncreated Grace of the Holy Trinity in the Works of Karl Rahner and St Gregory Palamas
Authors: Duncan Thomas
Published: February 2021

Eastern Orthodox theology in the 20th century experienced what has been referred to as a ‘Palamite renaissance,’ through a certain rediscovery of the works of the 14th-century archbishop and theologian, St Gregory Palamas. In the Christian West, 20th-century theology saw a great ‘return to the sources,’ among which Karl Rahner’s influential work played an important role in integrating elements of the scholastic tradition with that of the biblical and Greek patristic traditions. While there is a growing awareness and acceptance of Palamas’s teaching among Western scholars, many still view it as an incompatible obstacle to reconciliation between East and West. This article seeks to demonstrate that Karl Rahner’s work on grace and the Trinity, while remaining within its respective system and never mentioning Gregory Palamas, is at its heart identical to that of Palamas in several key areas, and that these two theologians may in fact provide a bridge for integrating the two traditions.
The effect of machining processes on the physical and surface characteristics of AA2024-B4C-SiC hybrid nanocomposites fabricated by hot pressing method
Authors: Çevik Zihni Alp , Karabacak Abdullah Hasan , Kök Metin , Canakçı Aykut , Kumar S Suresh , Varol Temel
Published: February 2021

In this study, an attempt was made on the AA2024 alloy based hybrid nanocomposites reinforced with different weight percentage of SiC and B4C particles to investigate their physical and machinability characteristics including surface morphology. The Material Removal Rate (MRR), Surface Roughness (SR) of the nanocomposites machined by various machining processes namely Abrasive Water Jet (AWJ) machining, Wire Electrical Discharge (WED) machining and Computer Numerical Controlled (CNC) turning processes were studied comparatively. The machined surface formed by the each machining process is examined and its surface quality was discussed for each hybrid nanocomposite. Results show that the hardness is increased to 101.6 BHN from 179.4 BHN, when 2 wt.% of B4C and SiC particles is added to AA2024 matrix. Observed from the results that the addition of 2 wt.% of B4C and SiC particles produces the highest porosity of 3.36% for nanocomposite samples. The experimental results revealed that the addition of particulates in to the matrix reduces the MRR and increases SR. MRR results showed that hybrid nanocomposites machined by AWJ technique has minimum MRR of 0.0221 mm3/min. The surface roughness of the nanocomposites machined with AWJ process was 3.2 µm and increased to 6.81 µm for the AA2024-B4C-SiC hybrid nanocomposites machined with CNC process.
Effect of aging temperature on a thermoset-like novel acrylic thermoplastic composite for marine vessels
Authors: Bel Haj Frej Haithem , Léger Romain , Perrin Didier , Ienny Patrick
Published: February 2021

This work aims at evaluating the durability of a carbon fibre reinforced thermoplastic composite under different aging conditions. The absorption and desorption of deionised water in carbon fibre (CF) reinforced Elium composite material were measured gravimetrically over two different temperatures. Water uptake experimental data were fitted to a Langmuir type diffusion model in order to identify and compare diffusion parameters and kinetics and to evaluate their dependence to aging conditions. It was found that the temperature increase had a significant effect only on saturation water uptake. Water desorption after aging was modelled accurately using Fick’s law and slight differences were found between model parameters. The effect of hydrothermal aging conditions and their reversibility were then evaluated by static and vibratory mechanical analysis. Results showed a slight and quasi-reversible reduction of longitudinal properties compared to shear properties at moderate aging temperature. While for higher aging temperature, the impact was found to be more significant and permanent on mechanical in-plane properties. Furthermore, static and modal results are confirmed by dynamic mechanical analysis, where the behaviour of studied material is differently affected by aging temperature, with a considerable increase in dried materials glass transition temperature.
Optimization and assessment of brake pad production parameters and organic Juniperus drupacea cone powder additive ratio using the Taguchi method
Authors: Aras Sait , Tarakçıoğlu Necmettin
Published: February 2021

In this study, an organic brake pad content was created to increase the overall tribological performance of the automobile brake system. Brake lining samples were obtained by hot molding method using juniperus drupacea cones powder which is not found in the literature in addition to barite, phenolic resin, fiber types (glass, carbon and basalt) and coke in the lining content. In order to determine the most ideal production conditions and content ratios, parameter combinations based on the L18(21 × 35) Taguchi orthogonal index were used according to the density, hardness, wear rate, friction coefficient objective functions. The density and hardness of the samples produced based on the orthogonal design were measured. A wear test was performed on a pin-on-disc type tribometer and the wear rate and friction coefficients were calculated according to the obtained values. Signal to noise ( S/N) ratio and ANOVA analysis were performed to determine the brake pad composition with the most ideal tribological properties. According to the results, the mixing time is 15 min., the molding temperature is 160 °C, the molding pressure is 100 MPa and the molding time is 15 min., have been found to be the optimum production conditions. In addition, it was observed that the density and hardness decreased as the amount of juniperus drupacea cone powder was increased. For this reason, it has been observed that the juniperus drupacea cone powder used for the first time in the brake lining composition can be used in lining content up to 25%, preferably up to 10% by weight.
Book review: Laura Dudley Jenkins. 2019. Religious Freedom and Mass Conversion in India
Authors: Vanlalhmangaiha
Published: February 2021

Laura Dudley Jenkins. 2019. Religious Freedom and Mass Conversion in India. Philadelphia: University of Pennsylvania Press. vi + 312 pp. Figures, notes, bibliography, index. $89.95 (hardback).
EBV Positive Lymphomatoid Granulomatosis Following Dental Extractions
Authors: Derbyshire Joseph , Fornelli Rick , Mascia Brent
Published: February 2021

Epstein-Barr virus (EBV) associated lymphoproliferative disorders includes a diverse group of diagnoses, encompassing both B-cell and T-cell lineages. With EBV mucocutaneous ulcers becoming a World health Organization diagnosis in 2018, introduction of the disease entity will be beneficial to the practicing otolaryngologist. We are reporting a case of a 69-year-old male with history of rheumatoid arthritis on methotrexate, recently undergoing dental extractions, who then developed multiple oral ulcerations and bony erosions of his palate and alveolar ridge. Associated symptoms included a large 3.0 cm neck mass, splenomegaly, and pulmonary nodules. Histopathology showed EBV+ lymphomatoid granulomatosis. Upon removal of immunosuppressive agent, patient’s symptoms improved with resolution of oral lesions, as well as systemic symptoms.
Late traumatic ventricular septal rupture
Authors: Palangadan Shaji , Padmaja Narayanan Nair Padmavati Amma , Karavathukudy Azeez Ameer , Sundarsingh Subash , Cherian Vijay Thomas , Vijayaraghavan Govindan
Published: February 2021

Traumatic ventricular septal rupture is a rare complication of blunt trauma to the chest and is lethal if unidentified. Although majority of these present early, late presentation can also occur. We describe a patient with severe head injury who deteriorated three weeks after trauma due to late development of ventricular septal rupture.
A Student’s Guide to the Classification and Operationalization of Variables in the Conceptualization and Design of a Clinical Study: Part 1
Authors: Andrade Chittaranjan
Published: February 2021

Students without prior research experience may not know how to conceptualize and design a study. This article explains how an understanding of the classification and operationalization of variables is the key to the process. Variables describe aspects of the sample that is under study; they are so called because they vary in value from subject to subject in the sample. Variables may be independent or dependent. Independent variables influence the value of other variables; dependent variables are influenced in value by other variables. A hypothesis states an expected relationship between variables. A significant relationship between an independent and dependent variable does not prove cause and effect; the relationship may partly or wholly be explained by one or more confounding variables. Variables need to be operationalized; that is, defined in a way that permits their accurate measurement. These and other concepts are explained with the help of clinically relevant examples.
A look into the practices and challenges of assessing young EFL learners’ writing in Croatia
Authors: Patekar Jakob
Published: February 2021

Writing in a foreign language is a particularly difficult skill to develop, especially when young learners are concerned because they are parallelly learning to write in their L1 and do not have strong oral foundations in their L2. The issue becomes even more complex when the ways to assess young learners’ writing are considered, given that research has shown there is room for improvement regarding English language teachers’ assessment literacy. Therefore, the aim of this paper is to examine the practices and challenges of assessing the writing of young EFL learners in Croatia. In the first part of the study, 97 English language teachers working with learners from year 1 to year 4 of elementary school (children aged 7 to 10) took an online questionnaire with close-ended and open-ended questions. In the second part, I analyzed the writing tasks that the learners were assigned by the teachers in the school. The results show that teachers do not always use appropriate writing tasks for summative assessment, that they need more support in creating language tests, and that Croatian universities need to do more to prepare future teachers to teach and assess young English language learners.
CT findings and dynamic imaging changes of COVID-19 in 2908 patients: a systematic review and meta-analysis
Authors: Zhou Xiuxiu , Pu Yu , Zhang Di , Xia Yi , Guan Yu , Liu Shiyuan , Fan Li
Published: February 2021

Quick screening patients with COVID-19 is the most important way of controlling transmission by isolation and medical treatment. Chest computed tomography (CT) has been widely used during the initial screening process, including pneumonia diagnosis, severity assessment, and differential diagnosis of COVID-19. The course of COVID-19 changes rapidly. Serial CT imaging could observe the distribution, density, and range of lesions dynamically, monitor the changes, and then guide towards appropriate treatment. The aim of the review was to explore the chest CT findings and dynamic CT changes of COVID-19 using systematic evaluation methods, instructing the clinical imaging diagnosis. A systematic literature search was performed. The quality of included literature was evaluated with a quality assessment tool, followed by data extraction and meta-analysis. Homogeneity and publishing bias were analyzed. A total of 109 articles were included, involving 2908 adults with COVID-19. The lesions often occurred in bilateral lungs (74%) and were multifocal (77%) with subpleural distribution (81%). Lesions often showed ground-glass opacity (GGO) (68%), followed by GGO with consolidation (48%). The thickening of small vessels (70%) and thickening of intralobular septum (53%) were also common. The dynamic changes of chest CT manifestations showed that lesions were absorbed and improved gradually after reaching the peak (80%), had progressive deterioration (55%), were absorbed and improved gradually (46%), fluctuated (22%), or remained stable (26%). The review showed the common and key CT features and the dynamic imaging change patterns of COVID-19, helping with timely management during COVID-19 pandemic.
Predicting Risk of Recurrent Patellofemoral Instability With Measurements of Extensor Mechanism Containment
Authors: Weltsch Daniel , Chan Calvin T. , Mistovich R. Justin , Urwin John W. , Gajewski Christopher R. , Fabricant Peter D. , Lawrence J. Todd R.
Published: February 2021

Background:

Identifying risk factors for recurrent patellar dislocation after a primary dislocation may help guide initial treatment. Magnetic resonance imaging (MRI) measurements relating the alignment of the extensor mechanism to trochlear morphology have been shown to distinguish patients with dislocations from controls, but their usefulness in predicting the risk of a second dislocation is not known.

Purpose:

To identify the association of novel MRI measures of patellar containment with recurrent instability in pediatric patients presenting with a first-time patellar dislocation.

Study Design:

Cohort study (Prognosis); Level of evidence, 3.

Methods:

The study was conducted at a tertiary care children’s hospital (2005-2014) on patients (age, 8-19 years) with a first-time patellar dislocation. MRI measurements were made by 2 independent raters. Interobserver reliability was assessed for all measurements via an intraclass correlation coefficient (ICC). Only measurements with an ICC >0.8 were included. Univariable and multivariable logistic regression analyses were used to evaluate variables associated with recurrence.

Results:

A total of 165 patients with a median age of 14 years and a slight (57.6%) female predominance was identified. The median follow-up length of the whole cohort was 12.2 months (interquartile range, 1.6-37.1 months). Subsequent instability was documented in 98 patients (59.4%). MRI measurements with excellent correlation (ICC > 0.8) were the tibial tubercle to trochlear groove distance (TT-TG), the tangential axial width of the patella, the tangential axial trochlear width, the axial width of the patellar tendon beyond the lateral trochlear ridge (LTR), and the tibial tubercle to LTR distance. In univariate analysis, all mentioned MRI measurements had significant association with recurrent instability. However, after both backward and forward stepwise regression analyses, the tibial tubercle to LTR distance was the only independent predictor of recurrent instability ( P = .003 in both). Patients with a tibial tubercle to LTR distance value greater than –1 mm had a significantly higher rate of recurrent patellar dislocation (72%).

Conclusion:

Of numerous axial view MRI parameters, only the tibial tubercle to LTR distance demonstrated a statistically significant association with recurrent patellar instability upon multivariable logistic regression analysis during short-term follow-up of a pediatric population presenting with initial lateral patellar dislocation. Interobserver correlation of the tibial tubercle to LTR distance was good (ICC > 0.8) and similar to that of TT-TG.
Investigating Crime Pattern Stability at Micro-Temporal Intervals: Implications for Crime Analysis and Hotspot Policing Strategies
Authors: Hart Timothy C.
Published: February 2021

Studies of crime hotspot forecasts use various metrics to describe different characteristics of prediction patterns. However, few investigations consider how the stability of crime hotspot, estimated at relatively short temporal intervals, can impact hotspot policing efforts. In response, using address-level incident location data that were collected from six law enforcement agencies in the United States, the current study examines the daily stability of crime hotspots that were estimated over a 1-year period. Results suggest that micro-temporal stability patterns in crime hotspot forecasts are dependent on crime type, jurisdiction, and the interaction between these two factors. Implications for crime analysis and future research are discussed.
Arms transfers and international relations theory: Situating military aircraft sales in the broader IR context
Authors: Willardson Spencer L , Johnson Richard AI
Published: February 2021

Quantitative research on arms transfers has not adequately accounted for broader theories of international relations. We review the specialized literature on arms transfers and examine how arms transfers fit with the broad international relations theories. We derive and test seven hypotheses based on realist, liberal and constructivist theories using a dataset of all non-US/Russian aircraft transfers between 1990 and 2010. We find limited support for realist hypotheses. We find little support for hypotheses derived from the Democratic Peace literature, but some support for liberal trade arguments. We also find some support for constructivist arguments based on shared identity and prestige measures.
‘Reconceptualising internationalisation through students’ eyes’: Findings from a biographical study of female, international doctoral students in an Irish University
Authors: Moran Lisa , Green Lorraine , Warren Simon
Published: February 2021

This paper presents findings from an Irish qualitative study of postgraduate, female, international students. It focuses on their narrations of internationalisation, in respect of events leading them to become international students, and their reflections on their academic, interpersonal and societal experiences in Ireland. International students are generally understudied and marginalised as metaphorical ‘others’ within global education policies, often being reduced to mere recruitment and financial targets and units of analysis. However, this study shows that international students transcend widespread but static assumptions about them being in academic and social deficit when transitioning to life in another country and negotiating new educational contexts. Significantly, our interviewees discursively positioned themselves in multifarious ways in relation to Irish higher education curricula, drawing on various discourses to define their internationalisation journeys. Although the sample size is small and confined to female postgraduates, our data suggests that university policies in Ireland and internationally largely overlook the multidimensionality of international doctoral students’ experiences. In our conclusion, we tentatively suggest ways in which international students’ academic and intercultural experiences could in the future be enriched, and how international students themselves could more fruitfully contribute to Irish higher education.
Gelatin-loaded cubosomes stabilized with hydrophobically modified quaternized cellulose nanofiber and their pH-dependent release property
Authors: Park Seok Ho , Zhao Fanyu , Park Soo Chan , Kim Jin-Chul
Published: February 2021

Monoolein cubic phase immobilizing hydrophobically modified gelatin (HmGel) in its water channel was prepared by a melt-hydration method. The cubic phase was micronized into cubosomes by using hydrophobically modified quaternized cellulose nanofiber (HmQCNF) as a stabilizer. The phase transition temperature of the cubic phase was about 68–70 °C. Small angle X-ray diffraction revealed that HmGel-loaded cubosome stabilized with HmCNF was a diamond type of cubic phase. HmGel-loaded cubosomes stailized with HmQCNF were dependent on the pH value in terms of the release of their payload (i.e, methylene blue) much more strongly than HmGel-loaded cubosomes stabilized with Pluronic F127.
Osteogenic capability of strontium and icariin-loaded TiO2 nanotube coatings in vitro and in osteoporotic rats
Authors: Zhu Ye , Zheng Tianxia , Wen Li-ming , Li Ren , Zhang Yan-bo , Bi Wen-juan , Feng Xiao-jie , Qi Meng-chun
Published: February 2021

Titanium (Ti) and Ti alloys are widely used biomaterials, but they lack osteogenic capability for rapid bone integration. To improve osseointegration of Ti implants, TiO2 nanotubes were prepared using the anodizing oxidation technique, and strontium (Sr) combined with icariin (ICA) was loaded on TiO2 nanotube coatings. Cell adhesion and proliferation of MC3T3-E1 cells, alkaline phosphatase (ALP) activity, mineralization of extracellular matrix, and bone formation around titanium implants in ovariectomized rats, were examined separately. The results showed that compared with pure Ti, TiO2 and Sr-loaded TiO2 coatings, the coatings loaded with both Sr and ICA showed better effect on cell adhesion and proliferation, higher ALP activity and more red-stained mineralized nodules. Furthermore, more bone was formed around implants loaded with both Sr and ICA in osteoporotic rats. Therefore, coating with Sr and ICA is valuable for clinical application to strengthen the osseointegration of titanium implants, especially in osteoporotic patients.
“…[T]his is What We are Missing”: The Value of Communicating Infant Feeding Information Across Three Generations of African American Women
Authors: Woods Barr Alexis L. , Austin Deborah A. , Smith Jacquana L. , Schafer Ellen J.
Published: February 2021

Background

Breast/Chestfeeding remains a public health issue for African Americans, and increased rates would mitigate many health disparities, thus promoting health equity.

Research Aims

To explore the interplay of generational familial roles and meaning (or value) ascribed to communicating infant feeding information across three generations.

Method

This prospective, cross-sectional qualitative study used an asset-driven approach and was guided by Black Feminist Thought and Symbolic Interactionism. African American women ( N = 35; 15 family triads/dyads), residing in the southeastern United States were interviewed. Data were analyzed using thematic analysis.

Results

The older two generations described their role using assertive yet nurturing terms, while the younger generation carefully discussed the flexibility between their familial roles. Emergent themes described the meaning each generation attributed to communicating infant feeding information: “My Responsibility,” “Comforting,” “Bonding Experience,” “She Cared,” and “Gained Wisdom.”

Conclusions

Our findings have potential to contribute to achieving health equity in African American families. Future breast/chestfeeding promotion efforts may benefit from reframing the current approach to including protection language and not solely support language. Lactation professionals should further recognize and support strengths and resource-richness of intergenerational infant feeding communication within African American families using strength-based, empowerment-oriented, and ethnically sensitive approaches.
Research on electric vehicle thermal management system with coupled temperature regulation between crew cabin and power battery pack
Authors: Han Bing , Liu Fei , Li Meng , Guo Jiale , Xu Yalong
Published: February 2021

Based on the structure of the thermal management system for electric vehicles, complete the design of the thermal management system for the whole vehicle, and realize the coupling temperature regulation between the vehicle cabin and the power battery pack. A direct cooling system model containing electric compressors, electronic expansion valves, heat exchangers, power battery packs, and other components coupled to the air conditioning system is established. Based on this, a vehicle thermal management model of the entire vehicle including electric vehicle, electric motor, high and low voltage network, vehicle cabin, air conditioning system, and power battery pack is completed. Develop the logic threshold control strategy, compressor speed control strategy, and electronic expansion valve opening control strategy for the vehicle thermal management system. Through the comparative analysis of the temperature control effect of the thermal management system on the cabin and the power battery pack under different ambient temperatures, the effect of different temperatures on the vehicle range is analyzed. The results show that this vehicle thermal management system can meet the requirements for battery pack heat dissipation and vehicle cabin refrigeration.
An estimation algorithm for tire wear using intelligent tire concept
Authors: Li Bo , Quan Zhenqiang , Bei Shaoyi , Zhang Lanchun , Mao Haijian
Published: February 2021

Real-time monitoring of tire wear is a hot spot in the research of automobile tires, and it has a great significance to ensure the safety of automobile driving. A tire wear estimation algorithm was proposed based on the relevant knowledge of finite element modal analysis theory and the concept of intelligent tires in this paper. First, the finite element model of the 205/55/R16 radial tire was established through the ABAQUS software, then the finite element method was used to simulate and analyze the influence of tire inflation pressure, load, tire wear, and speed on the tire radial vibration frequency. The simulation results show that inflation pressure and tire wear shows an upward trend with the increase of the vibration frequency of each order in the tire radial direction, and load and speed increase with what increases of tire radial increase frequency. Based on simulation analysis data, combined with the relationship between tire inflation pressure, load, tire wear, speed, and radial vibration frequency, a neural network-based tire wear estimation algorithm is proposed. The estimate results show that the predicted wear curve and the actual wear curve have a higher degree of overlap, the average error is 0.0874 mm, and the average error percentage is 2.78%, Thus, a feasible tire wear estimation algorithm is proposed.
Classical hydraulic ram pump performance in comparison with modern hydro-turbine pumps for low drive heads
Authors: Kesharwani Siddhi , Tripura Kupulwng , Singh Punit
Published: February 2021

We present a unique comparison of two types of renewable hydro pumping devices, namely the ram and turbine pump having different working principles. This comparison is based on experiments with these pumping devices at a field station in a village in central-east India. Our work identifies the major gaps in the study of large ram pumps, covering the hydraulic scaling conformance to creation of a unified platform for the investigation of such pumping devices with respect to operating parameters like head, flow, efficiency and, most importantly, size. The field tests of ram revealed that its non-dimensional performance parameters fit perfectly on the theoretical scaling curves. The investigations further showed that while rams had more efficiency (53–62%), they could not handle more than 40–50 l/s of discharge. In comparison, the turbine pumps, tested in laboratory conditions, were more compact for flows beyond 100 l/s, but they settled for overall efficiencies between 49% and 55%. The study recommends a limiting design flow line for rams to be 50 l/s because of the size-factor. It further finds that for absolute flows between 50 and 100 l/s within the low-head range of 3–5 meters, the design of geometrical shapes for turbine pumps could be a challenge for optimized efficiencies. The head-discharge-diameter (H-Q-D) chart developed here is a useful way of interpreting the technology with respect to boundary conditions and it creates a roadmap for future inventions in such renewable hydro-pumping devices. The paper makes a case for axial flow pumps as turbines. It concludes with a call for the propagation of research on such nature-friendly pumping technologies, where most (90–95%) of the water is returned to the stream, paving the way for a new era of sustainability.
Performance prediction of transonic axial multistage compressor based on one-dimensional meanline method
Authors: Zhang Yingying , Zhang Shijie
Published: February 2021

This study proposes a 1D meanline program for the modeling of modern transonic axial multistage compressors. In this method, an improved blockage factor model is proposed. Work-done factor that varies with the compressor performance conditions is added in this program, and at the same time a notional blockage factor is kept. The coefficient of deviation angle model is tuned according to experimental data. In addition, two surge methods that originated from different sources are chosen to add in and compare with the new method called mass flow separation method. The salient issues presented here deal first with the construction of the compressor program. Three well-documented National Aerodynamics and Space Administration (NASA) axial transonic compressors are calculated, and the speedlines and aerodynamic parameters are compared with the experimental data to verify the reliability and robustness of the proposed method. Results show that consistent agreement can be obtained with such a performance prediction program. It was also apparent that the two common methods of surge prediction, which rely upon either stage or overall characteristic gradients, gave less agreement than the method called mass flow separation method.
Benefits and harms of breast cancer mammography screening for women at average risk of breast cancer: A systematic review for the European Commission Initiative on Breast Cancer
Authors: Canelo-Aybar Carlos , Ferreira Diogenes S , Ballesteros Mónica , Posso Margarita , Montero Nadia , Solà Ivan , Saz-Parkinson Zuleika , Lerda Donata , Rossi Paolo G , Duffy Stephen W , Follmann Markus , Gräwingholt Axel , Alonso-Coello Pablo
Published: February 2021

Objectives

Mammography screening is generally accepted in women aged 50–69, but the balance between benefits and harms remains controversial in other age groups. This study systematically reviews these effects to inform the European Breast Cancer Guidelines.

Methods

We searched PubMed, EMBASE and Cochrane Library for randomised clinical trials (RCTs) or systematic reviews of observational studies in the absence of RCTs comparing invitation to mammography screening to no invitation in women at average breast cancer (BC) risk. We extracted data for mortality, BC stage, mastectomy rate, chemotherapy provision, overdiagnosis and false-positive-related adverse effects. We performed a pooled analysis of relative risks, applying an inverse-variance random-effects model for three age groups (<50, 50–69 and 70–74). GRADE (Grading of Recommendations Assessment, Development and Evaluation) was used to assess the certainty of evidence.

Results

We identified 10 RCTs including 616,641 women aged 38–75. Mammography reduced BC mortality in women aged 50–69 (relative risk (RR) 0.77, 95%CI (confidence interval) 0.66–0.90, high certainty) and 70–74 (RR 0.77, 95%CI 0.54–1.09, high certainty), with smaller reductions in under 50s (RR 0.88, 95%CI 0.76–1.02, moderate certainty). Mammography reduced stage IIA+ in women 50–69 (RR 0.80, 95%CI 0.64–1.00, very low certainty) but resulted in an overdiagnosis probability of 23% (95%CI 18–27%) and 17% (95%CI 15–20%) in under 50s and 50–69, respectively ( moderate certainty). Mammography was associated with 2.9% increased risk of invasive procedures with benign outcomes ( low certainty).

Conclusions

For women 50–69, high certainty evidence that mammography screening reduces BC mortality risk would support policymakers formulating strong recommendations. In other age groups, where the net balance of effects is less clear, conditional recommendations will be more likely, together with shared decision-making.
Local and non-local damage model with extended stress decomposition for concrete
Authors: Ahmed Bilal , Voyiadjis George Z , Park Taehyo
Published: February 2021

In this work, a new damage model for concrete is proposed with an extension of the stress decomposition (limited to biaxial cases), to capture shear damage due to the opposite signed principal stresses. To extract the pure shear stress, the assumption is made that one component of the shear stress is a minimum absolute of the two principal stresses. The opposite signed principal stresses are decomposed into shear stress and uniaxial tensile/compressive stress. A local model is implemented in Abaqus UMAT and it is further extended to a non-local model by utilization of the gradient theory. The concept of three length scales (tension, compression, and shear) is kept the same as the recently proposed nonlocal damage model by the authors. The nonlocal model is implemented in the Abaqus UEL-UMAT subroutine with an eight-node quadrilateral user-defined element, having five degrees of freedom at corner nodes (displacement in X/Y direction and tensile/compressive and shear nonlocal equivalent strain) and two degrees of freedom at internal nodes. Some examples of a local model including uniaxial and biaxial loading are addressed. Also, five examples of mixed crack mode and mode-I cracking are presented to comprehensively show the performance of this model.
Nonlinear analysis of compliant robotic fish locomotion
Authors: Jiang Hongzhou , Liu Yanwen
Published: February 2021

Compliant robotic fish can achieve a better swimming performance than rigid-bodied robotic fish. Therefore, this article investigates the swimming behavior of the compliant robotic fish based on a new swimming model that combines the large-amplitude elongated-body theory with decoupled natural orthogonal complement matrices. The simulation reveals that the multi-order resonances are generated in tail-beat amplitude, forward speed, stride length, and transport efficiency when the compliant robotic fish is driven at the corresponding frequency. Moreover, the resonant effects demonstrate the nonlinear behaviors as the driving torque increases. A control strategy for resonance utilization is presented to improve the performance capabilities. The potential influence factors for resonant effects are also discussed, showing that the tail-generated hydrodynamic force significantly impacts the resonant effect. These nonlinear characteristics can provide important guidelines for the motion control of the compliant robotic fish.
Bearing internal load analysis and fatigue life estimation based on nonlinear dynamic model of a gear system
Authors: Kong Xiannian , Ding Han , Tang Jinyuan , Hu Zehua , Chen Siyu
Published: February 2021

The bearing internal load distribution and fatigue life estimation are accomplished based on the bearing static model at present, ignoring the gear engagement. Besides, bearings are modeled as a linear spring in gear dynamic models, failing to analyze bearing internal load. This article aims to study the bearing internal load fluctuation and corresponding bearing life in gear systems. A nonlinear dynamic model of the gear-bearing system is built, considering the time-varying mesh stiffness, the static transmission error, backlash, bearing clearance, and the nonlinear bearing force. The dynamic model is capable of calculating the bearing internal load. Based on the internal load, fatigue life is acquired using the linear damage theory. The numerical results show that the gear engagement has a significant influence on the bearing internal load analysis, in which periodic fluctuation is related to the mesh frequency and shaft frequency, resulting in the bearing life affected by gear meshing. Compared with the fatigue life predicted under the bearing static model, evident deviations are observed, pointing to the significant role of the gear engagement in the analysis of fatigue life estimation.
Low velocity impact and compression after impact behaviour of polyester pin-reinforced foam filled honeycomb sandwich panels
Authors: Jayaram RS , Nagarajan VA , Kumar KP Vinod
Published: February 2021

Hybridization of sandwich panels and their different components have drawn huge attention due to the significant improvement in their attributes. Hybrid core of ‘Polyester Pin-reinforced Foam filled Honeycomb Sandwich panels’ (PFHS) were fabricated and compared with unreinforced ‘Foam filled Honeycomb Sandwich panels’ (FHS) in terms of low velocity impact and Compression After Impact (CAI) performance. The impact damage area was calculated by employing MATLAB image processing technique. Incorporating through thickness pins for connecting faces and core is an effectual way to improve interfacial bonding, specific bending stiffness and also imparts out of plane properties for sandwich panels. The low velocity impact tests performed on the sandwich panels revealed that the polyester pin reinforcement in foam filled honeycomb sandwich panel improved the load bearing capacity, total absorbed energy and reduced the impact damage area significantly. In CAI test, debond, wrinkling of face sheet, and buckling of face sheet and core are the major modes of failure. The addition of the pins enhanced the compressive strength for all the impact energy levels.
Airborne sound insulation prediction of masonry walls using artificial neural networks
Authors: Fabio Serpilli , Giovanni Di Nicola , Mariano Pierantozzi
Published: February 2021

In this paper, an alternative method for the calculation of masonry walls sound insulation is investigated. Thirty-four simple monolithic brick walls were examined. For the considered walls, the measurements made by accredited laboratories in compliance with ISO 10140 standard were collected. For each building element, the experimental measurements and all the information concerning the geometric and physical characteristics of all the components (material, dimensions, mass, density, Young’s modulus, Poisson’s module, hole content, etc.) were classified. Then, from the collection of measurements obtained in the standard laboratories and the division of them into homogeneous groups, a statistical sensitivity analysis to determine the most statistically significant parameter for the sound insulation of building walls was carried out. This analysis was a useful tool for selecting parameters to be used in forecast models and for calculating statistical effects. Finally, an alternative method based on the use of artificial neural networks (ANN) was proposed. This paper discusses the results obtained by applying the models to a specific kind of construction: the masonry walls. The results will show a good correlation of the values obtained on this first type of building construction. This encourages the extension of the method explained in this work to other types of walls.