bluuebunny/crossref_metadata_2025 huggingface dataset:
Rotational Stability of Plastic Hinges
Authors: Roberts Michael J , Davies J Michael
Published: September 2021

This paper is part of a larger project that considers the design of large steel‐framed warehouses and distribution centres (‘Big Sheds’) in the context of the SCOSS Alert “Effects of Scale” [1]. These buildings are currently designed to Standards and design procedures that were intended for much smaller structures, and are now long out of date. In the UK, the steel frames of such buildings are generally designed on the basis of plastic theory [2], the fundamental research initiated at the University of Cambridge being continued under Horne at the University of Manchester and culminating in the publication in 1981 of Horne and Morris [3]. Since that date, design procedures have largely stood still while Big Sheds have increased enormously in both scale and complexity. In the UK, plastic design is still largely used; while the early design procedures have been automated so that the entire calculation can be dedicated to a computer. Nevertheless, the fundamental plastic design procedures have changed little. In this context, which is continuing to evolve, this paper returns to the fundamentals and questions some of the basic premises. Current design procedures, based on laboratory tests on small stocky sections, can only be extrapolated to the contemporary situation with the aid of advanced numerical modelling and this process has only just begun. Even at this early stage of the research, it is suggested that the use of plastic theory for the design of large structures typified by Big Sheds needs serious reconsideration.
Holistic Life‐Cycle Analysis of Bridge Solutions
Authors: Zinke Tim , Hechler Oliver , Rademacher Dennis
Published: September 2021

Steel in bridge constructions is often associated with very large span bridges due to its favorable relationship between strength and weight. But even for bridges with small and medium spans of up to 60 m, steel combined with concrete as a composite bridge can lead to economically justifiable constructions, especially when the performance during the complete life‐cycle is integrated. In this paper, two life‐cycle oriented calculation methods (life‐cycle costs and external costs) are introduced and applied. As a result, comparisons between two abutment solutions (conventional reinforced concrete abutment and a permanent steel sheet pile abutment) and two superstructure variants (steel composite construction and in‐situ prestressed concrete superstructure) are presented. It is shown that accelerated construction processes, durable materials, and a smart bridge‐design considering actual technological developments lead to economically advantageous solution for traffic infrastructures.
Optimized welding processes for the repair and strengthening of structures made of old mild steels
Authors: Sieber Lars , Flederer Holger
Published: September 2021

When repairing or reinforcing existing structures made of old mild steel, the preferred joining method may be welding rather than bolting, as is usually the case. Due to the specific properties of old mild steels, special problems have to be considered. The weldability of old mild steels is particularly influenced by their highly scattering chemical composition, existing inclusions and their distribution in the component as well as their limited material toughness.

The first results of a research project at the Dresden University of Applied Sciences concerning the weldability of old rimmed mild steels have already been presented at Eurosteel 2017. This paper presents the findings of continued investigations, e.g. the use of other filler materials or out‐of‐position welding. The welding parameters were adjusted so that the toughness of the HAZ is better than in the unaffected base material.

Additionally, the suitability of flux‐cored wire welding of old mild steels was investigated. This welding process enables a more economical production of large seam lengths. Unfortunately, the realized process parameters are very stringent, as the higher energy density of this process quickly leads to coarse grain formation in the HAZ and thus to a reduction in toughness.
Stiffness of equal width welded I‐beam to RHS column connection
Authors: López‐Colina Carlos , Serrano Miguel A. , Lozano Miguel , Gayarre Fernando L. , Suárez Jesús M.
Published: September 2021

Despite some recent efforts, the use of mechanical approaches like the component method for the rotational stiffness of connections is still not present in the design codes for hollow sections. In addition, the easiest way to obtain semi‐rigid connections with high rotational stiffness or even rigid ones with I beams and RHS columns is to design both members with the same width. In this way, loads are transferred almost directly from the beam flanges to the side walls of the RHS, avoiding the high rotations due to the bending of the front face of the RHS. Considering all this, some experimental tests have been used by the authors to validate a finite element model that simulates equal width connections in which the component ‘lateral faces of RHS’ under transverse forces was the main source of beam rotation. This was selected as the most important component to be considered in the welded joints between I beams and RHS columns when they have the same width. Then, some different analytical approaches for its stiffness have been assessed by comparing them with the experimental and numerical results. This work finally proposes a design equation for the ‘lateral faces of RHS in tension or compression’ in order to be applied in a future unified proposal for the component method including hollow sections. In addition, a rotational stiffness approach for the equal width welded I‐to‐RHS connections has been directly derived from this.
Peculiarities of resistance definition for welded offset T‐joint between RHS members
Authors: Kalmykova Svitlana , Wald František
Published: September 2021

Steel structural hollow sections, including rectangular hollow sections (RHS), are nowadays one of the most efficient load‐bearing elements of the lattice structures. Despite its widespread application, there is still lack of design techniques for joints produced with offsets. The article intends to eliminate gaps in knowledge about the mechanical resistance and design of so‐called offset RHS joints, welded T‐joints composed from rectangular hollow sections with a certain lateral offset of a brace from a centreline of a chord, under brace axial compression. The paper presents results of numerical investigations of structural behaviour of the mentioned joints in comparison with existing analytical methods of connection nominal resistance determination for both standard (co‐axial) and offset welded RHS joints. For validation purposes, the full‐scale laboratory tests were conducted. Numerical models were created using a general FE programme Abaqus and a component‐based FE programme IDEA StatiCa. Particular attention was given to mesh size effect and weld seam modelling. The curve fitting analytical model complying to prEN1993‐1‐8:2020 proposed by Wei and Packer [1] is verified by numerical experiments. The limits of validity of considered analytical model are examined and proved by calculations.
Influence of energy input on the strength and hardness of welded joints
Authors: Kästner Thoralf , Stroetmann Richard
Published: September 2021

The changes in mechanical properties due to local energy input are important for welded joints. This affects both the base material in the area of the heat‐affected zone and the resulting weld seam. Extensive investigations on the influence of the cooling time t8/5, which is representative of the energy input, were carried out on a newly developed test specimen for determining the mechanical properties of welds. From these investigations, functional relationships between the strength class of the filler metal, the t8/5 time and the mechanical properties of the weld seam were derived. In order to evaluate the influence of multi‐layer welding, hardness measurements were carried out on individual weld beads at different levels of the welded joint. Furthermore, the relationship between the local hardness values and the integrally determined tensile strength was investigated.
Strain Design Limit for Hollow Section Joints
Authors: Kožich Matyáš , Jehlička Petr , Kuříková Marta , Wald František , Bu Xiao‐Ding , Packer Jeffrey A. , Kabeláč Jaromír
Published: September 2021

This paper focuses on discussions over establishing the design resistance of hollow section joints, which have now been ongoing for 30 years. The question arose once physical experiments could be replaced by numerical tests and was temporary solved by agreement on a displacement limit within IIW. With the advent of design by finite element (FE) solutions, and the application of high‐strength steels, it is being raised once more.

A number of design guides and standards, with considerable international consensus, now exist for the design of welded hollow section joints in onshore and offshore construction. These, however, typically cover relatively standardized joint types, geometries and loading cases. In the event of unusual joints, it is now common for finite element modelling to be performed, but specific guidance needs to be provided on acceptable FE modelling procedures and the interpretation of the output, in order for a suitable joint design resistance to be determined. Towards this objective, this paper describes appropriate FE modelling and ultimate limit states that can be used; in particular, a 5 % ultimate strain limit state. Application of these ultimate limit states is demonstrated using validated FE models for RHS‐to‐RHS (rectangular hollow section) X‐joints and branch plate‐to‐CHS (circular hollow section) joints, with branches loaded in axial compression.
Numerical assessment of stainless steel tubular T‐joints subjected to brace and chord axial forces
Authors: Nogueira Mateus M. , de Lima Luciano R. O. , da S. Vellasco Pedro C. G. , Young Ben
Published: September 2021

The utilisation of tubular sections in steel structures has increased significantly worldwide. The use of stainless steel provides several benefits for structures, including high corrosion resistance, durability, fire resistance and ease of maintenance. A significant issue in the design of tubular structures is the joints failure since they are highly susceptible to local failures that influence their actual overall behavior. The design rules of welded carbon steel tubular joints are available, such as Eurocode 3, part 1‐8, NBR 16239, ISO 14346 and CIDECT guides. When stainless steel tubular joints are considered, the AS/NZS 4673 Australian/New Zealand Standard is the only available specification that can be used. An experimental and numerical analysis of these tubular joints are recommended since they enable a more accurate evaluation of their structural performance. Concerning these aspects, this work aims to investigate stainless steel tubular T‐joints fabricated by SHS and RHS cold‐formed profiles that focused on the effect of chord pre‐loading. For this purpose, a numerical study based on finite element analysis was performed. The finite element model was developed and calibrated against experiments. The results were subsequently compared with the aforementioned design predictions.
The influence of driving imperfections on the water pressure resistance of HZ®‐M/AZ walls
Authors: Chrzanowski Maciej , Boueiz Perla El , Matos Rui , Zillgen Heiko , Even Boris
Published: September 2021

The HZ®‐M/AZ system is widely used around the world as an efficient retaining wall solution, mainly in port structures and deep excavations. The use of walls made up of AZ infill steel sheet piles and HZ®‐M king piles, is one of the main solutions for high retaining quay walls. When the wall is subjected to high hydraulic pressure, the wall behaviour under this load case is one of the topics of high importance.

The resistance to water pressure of the nominal systems can be found in the dedicated ArcelorMittal brochure “The HZ®‐M Steel Wall System 2020”.

Tolerable driving imperfections are agreed between the contractual parties. The final position of the HZ®‐M bearing elements will lead to an actual wall geometry which, in some rare cases, can affect the stress state of the wall elements subject to high water pressure.

This paper tackles the topic of the effect of these driving imperfections on the HZ®‐M/AZ wall, related to misplacements of the HZ®‐M piles and the corresponding consequence on the wall resistance to water pressure.

Based on validated numerical models, an analytical tool is now available, allowing a quick assessment of the actual water pressure resistance of HZ®‐M/AZ walls with respect of measured driving imperfections at site.
Lithium‐based Loop for Ambient‐Pressure Ammonia Synthesis in a Liquid Alloy‐Salt Catalytic System
Authors: Tang Zujian , Meng Xian , Shi Yue , Guan Xiaofei
Published: September 2021

The Haber‐Bosch process for ammonia (NH3) production in industry relies on high temperature and high pressure and is therefore highly energy intensive. In addition, the activity of the solid transition metal‐based catalysts used is typically limited by the scaling relation between activation barrier for N2 dissociation and nitrogen‐binding energy. Here, an innovative Li‐based loop in a liquid alloy‐salt catalytic system for ambient‐pressure NH3 synthesis from N2 and H2 was developed. The looping process consisted of three reaction steps taking place simultaneously. The first step was the nitrogen fixation by Li in the liquid Li−Sn alloy to form lithium nitride (Li3N), which floated up and dissolved into the molten salt. The second step was the hydrogenation of the Li3N to produce NH3 and lithium hydride (LiH) in the molten salt. The third step was the decomposition of the LiH to regenerate Li in the presence of Sn. An average NH3 yield rate of 0.025 μg s−1 was achieved in an 81 h test at 510 °C and ambient pressure. The floating and dissolution of Li3N realized in the liquid catalytic system enabled circumventing the scaling relation exerted on Li, and the remarkable properties of liquid alloy and molten salt offered extraordinary advantages for NH3 synthesis at ambient pressure.
Enhancing cross‐cultural evaluation practice through kaupapa Māori evaluation and boundary critique: Insights from Aotearoa New Zealand
Authors: Hepi Maria , Foote Jeff , Ahuriri‐Driscoll Annabel , Rogers‐Koroheke Marara , Taimona Hone , Clark Andrea
Published: September 2021

In Aotearoa New Zealand, concern about the impact of colonisation and experience of institutional racism has led to calls for evaluative practice to be firmly grounded in a Māori worldview to reflect indigenous values and avoid deficit framings. With this in mind, our evaluation projects have been informed by a blend of kaupapa Māori evaluation and boundary critique to ensure that our systemic inquiries were responsive to hapū aspirations. We focus on the role that boundary critique played in supporting our cross‐cultural evaluation practice. Applying boundary critique enabled the expansion of the evaluand to encompass hapū values and outcomes from a te ao Māori/hapū perspective. We posit that boundary critique is useful when undertaking cross‐cultural evaluations as it provides a way to make explicit the different values of te ao Māori (the Māori world) and te ao Pākehā (the Western World).
“Leveling up” for change: Application of a multilevel system capacity change model to evaluate U.S. Department of Defense global health engagement activities
Authors: Reed Eva , Harwood James , Jackson Jessica L. A. , Gebreyesus Tsega
Published: September 2021

Evaluating within complex systems is challenging because of how complexity affects the identification and observation of outcomes. U.S. Department of Defense (U.S. DoD) capacity building global health engagements are often difficult to measure due to the conflation of levels of analysis and confounding variables, hindering the explanation of change effects. This article will illustrate two case examples where a boundary‐driven systems framework was utilized to integrate systems thinking into U.S. DoD capacity building programs and associated evaluations. The findings from the first case led to developing a theory of change that was later tested and refined in the second case to establish the multilevel system (MLS) concept model. Based on these findings, the four distinct system boundaries and subcomponents of the MLS concept model were refined to include changes within the organizational system. The development of the MLS model allowed for the explicit framing of efforts, measurement and analysis, and the alignment of program activities and observed outcomes; while still allowing for the illumination of emergent change effects in a complex system.
Individual differences in representational similarity of first and second languages in the bilingual brain
Authors: Nichols Emily S. , Gao Yue , Fregni Sofia , Liu Li , Joanisse Marc F.
Published: September 2021

Current theories of bilingualism disagree on the extent to which separate brain regions are used to maintain or process one's first and second language. The present study took a novel multivariate approach to address this question. We examined whether bilinguals maintain distinct neural representations of two languages; specifically, we tested whether brain areas that are involved in processing word meaning in either language are reliably representing each language differently, and whether language representation is influenced by individual differences in proficiency level and age of acquisition (AoA) of L2. Thirty‐one English–Mandarin bilingual adults performed a picture–word matching task in both languages. We then used representational similarity analysis to examine which brain regions reliably showed different patterns of activity for each language. We found that both proficiency and AoA predicted dissimilarity between language representations in several brain areas within the language network as well as several regions of the ventral visual pathway, demonstrating that top‐down language knowledge and individual language experience shapes concept representation in this processing stream. The results support the model of an integrated language system in bilinguals, along with a novel description of how representations for each language change with proficiency level and L2 AoA.
Cumulative menstrual months and breast cancer risk by hormone receptor status and ethnicity: The Breast Cancer Etiology in Minorities Study
Authors: Cole Sarah E. , John Esther M. , Hines Lisa M. , Phipps Amanda I. , Koo Jocelyn , Ingles Sue A. , Baumgartner Kathy B. , Slattery Martha L. , McKean‐Cowden Roberta , Wu Anna H.
Published: September 2021

Reproductive and hormonal factors may influence breast cancer risk via endogenous estrogen exposure. Cumulative menstrual months (CMM) can be used as a surrogate measure of this exposure. Using harmonized data from four population‐based breast cancer studies (7284 cases and 7242 controls), we examined ethnicity‐specific associations between CMM and breast cancer risk using logistic regression, adjusting for menopausal status and other risk factors. Higher CMM was associated with increased breast cancer risk in non‐Hispanic Whites, Hispanics and Asian Americans regardless of menopausal status (all FDR adjusted P trends = .0004), but not in African Americans. In premenopausal African Americans, there was a suggestive trend of lower risk with higher CMM. Stratification by body mass index (BMI) among premenopausal African American women showed a nonsignificant positive association with CMM in nonobese (BMI <30 kg/m2) women and a significant inverse association in obese women (OR per 50 CMM = 0.56, 95% CI 0.37‐0.87, Ptrend = .03). Risk patterns were similar for hormone receptor positive (HR+; ER+ or PR+) breast cancer; a positive association was found in all premenopausal and postmenopausal ethnic groups except in African Americans. HR− (ER− and PR−) breast cancer was not associated with CMM in all groups combined, except for a suggestive positive association among premenopausal Asian Americans (OR per 50 CMM = 1.33, P = .07). In summary, these results add to the accumulating evidence that established reproductive and hormonal factors impact breast cancer risk differently in African American women compared to other ethnic groups, and also differently for HR− breast cancer than HR+ breast cancer.
An automated approach for fringe frequency estimation and removal in infrared spectroscopy and hyperspectral imaging of biological samples
Authors: Solheim Johanne Heitmann , Borondics Ferenc , Zimmermann Boris , Sandt Christophe , Muthreich Florian , Kohler Achim
Published: September 2021

In infrared spectroscopy of thin film samples, interference introduces distortions in spectra, commonly referred to as fringes. Fringes may alter absorbance peak ratios, which hampers the spectral analysis. We have previously introduced extended multiplicative signal correction (EMSC) for fringes correction. In the current article, we provide a robust open‐source algorithm for fringe correction in infrared spectroscopy and propose several improvements to the Fringe EMSC model. The suggested algorithm achieves a more precise fringe frequency estimation by mean centering of the measured spectrum and applying a window function prior to the Fourier transform. It selects two frequencies from a user defined number of maxima in the Fourier domain. The improved Fringe EMSC algorithm is validated on two experimental datasets, one of them being a hyperspectral image. Techniques for separating sample spectra from background spectra in hyperspectral images, and techniques to identify spectra affected by fringes are also provided.
Scientific premise for the involvement of neutrophil extracellular traps (NETs) in vaccine-induced thrombotic thrombocytopenia (VITT)
Authors: Kashir Junaid , Ambia Ayesha Rahman , Shafqat Areez , Sajid Muhammad Raihan , AlKattan Khaled , Yaqinuddin Ahmed
Published: September 2021

Following on from the devastating spread of COVID-19, a major global priority has been the production, procurement, and distribution of effective vaccines to ensure that the global pandemic reaches an end. However, concerns were raised about worrying side effects, particularly the occurrence of thrombosis and thrombocytopenia after administration of the Oxford/AstraZeneca and Johnson & Johnson's Janssen COVID-19 vaccine, in a phenomenon being termed vaccine-induced thrombotic thrombocytopenia (VITT). Similar to heparin-induced thrombocytopenia (HIT), this condition has been associated with the development of anti-platelet factor 4 antibodies, purportedly leading to neutrophil-platelet aggregate formation. Although thrombosis has also been a common association with COVID-19, the precise molecular mechanisms governing its occurrence are yet to be established. Recently, increasing evidence highlights the NLRP3 (NOD-like, leucine-rich repeat domains, and pyrin domain-containing protein) inflammasome complex along with IL-1β and effete neutrophils producing neutrophil extracellular traps (NETs) through NETosis. Herein, we propose and discuss that perhaps the incidence of VITT may be due to inflammatory reactions mediated via IL-1β/NLRP3 inflammasome activation and consequent overproduction of NETs, where similar autoimmune mechanisms are observed in HIT. We also discuss avenues by which such modalities could be treated to prevent the occurrence of adverse events and ensure vaccine rollouts remain safe and on target to end the current pandemic.
Immunogenicity after two doses of inactivated virus vaccine in healthcare workers with and without previous COVID‐19 infection: Prospective observational study
Authors: Yalçın Tuğba Y. , Topçu Deniz İ. , Doğan Özlem , Aydın Saliha , Sarı Nuran , Erol Çiğdem , Kuloğlu Zeynep E. , Azap Özlem K. , Can Füsun , Arslan Hande
Published: September 2021

Vaccines have been seen as the most important solution for ending the coronavirus disease 2019 (COVID‐19) pandemic. The aim of this study is to evaluate the antibody levels after inactivated virus vaccination. We included 148 healthcare workers (74 with prior COVID‐19 infection and 74 with not). They received two doses of inactivated virus vaccine (CoronaVac). Serum samples were prospectively collected three times (Days 0, 28, 56). We measured SARS‐CoV‐2 IgGsp antibodies quantitatively and neutralizing antibodies. After the first dose, antibody responses did not develop in 64.8% of the participants without prior COVID‐19 infection. All participants had developed antibody responses after the second dose. We observed that IgGsp antibody titers elicited by a single vaccine dose in participants with prior COVID‐19 infection were higher than after two doses of vaccine in participants without prior infection (geometric mean titer: 898 and 607 AU/ml). IgGsp antibodies, participants with prior COVID‐19 infection had higher antibody levels as geometric mean titers at all time points (p < 0.001). We also found a positive correlation between IgGsp antibody titers and neutralizing capacity (rs = 0.697, p < 0.001). Although people without prior COVID‐19 infection should complete their vaccination protocol, the adequacy of a single dose of vaccine is still in question for individuals with prior COVID‐19. New methods are needed to measure the duration of protection of vaccines and their effectiveness against variants as the world is vaccinated. We believe quantitative IgGsp values may reflect the neutralization capacity of some vaccines.
Optimized deeplearning‐basedattack detection framework for secure virtualized infrastructures in cloud
Authors: Gupta Bhavana , Mishra Nishchol
Published: September 2021

Virtualization is the foundation of cloud computing process and allows more effective utilization of physical computer hardware. Virtualization technologies are used in various tasks for the improvement of operating systems. Virtualization is meant for enabling the entire representation of cloud computing systems on normal speed. Still, the scale of virtualized environments and its complexity is found to be difficult in this process. This paper introduces a security analytics method in virtualized infrastructure for detecting the attacks of cloud computing. As the work relies on big data issues based on the features of network behavior, the detection phase is processed under two major phases: (1) feature extraction and (2) classification. In the feature extraction phase, proposed holoentropy features are extracted along with exponential moving average features. These extracted features are then subjected to the classification process, where the optimized DBN is used to detect the presence of an attack in network. To make the detection more accurate, the weights are optimally tuned by a new hybrid elephant monarch algorithm that helps in DBN learning. At last, the performance of the proposed work is computed over other traditional models in terms of certain measures.
NIR Light Stimulated Self‐Healing Reduced Tungsten Oxide/Polyurethane Nanocomposite Based on the Diels−Alder Reaction
Authors: Motora Kebena Gebeyehu , Wu Chang‐Mou , Chang Cheng‐Chieh , Liao Jui‐Hong
Published: September 2021

Cracks formed in materials can influence the performances and shorten their lifetime. Self‐healing materials can repair cracks caused by mechanical damage using external stimuli, which increases their safety, extend their service life, and can save renovation costs. In this work, a novel thermo‐responsive linear Diels‐Alder polyurethane (DAPU) and reduced tungsten oxide (WO3−x) (W‐DAPU) is developed for the first time. Its near‐infrared (NIR) light‐induced self‐healing properties are evaluated using qualitative optical observation and quantitative tensile measurements. The NIR light‐induced self‐healing and photothermal conversion property of W‐DAPU is also systematically investigated. The results show that linear DAPU has an excellent thermo‐reversible self‐healing efficiency of 94.8% and heals within 6 s due to the presence of a DA bond. In addition, the W‐DAPU has a self‐healing efficiency of 83.2% with outstanding photothermal conversion. This study paves the way to design and fabricate stimuli‐responsive nanocomposite materials for various applications.
Combination of absorptive notch filter and tunable dual‐band conventional notch filter
Authors: Bayati Mohammad Sajjad , Mousavi Seyed Mohammad Hadi , Makki Seyed Vahab Al‐Din
Published: September 2021

In this paper, a new kind of absorptive bandstop filter composing three series‐coupled lines is designed, investigated, and fabricated. The proposed circuit is indeed a combination of a dual‐band conventional notch filter and a single‐band absorptive filter generating two conventional and an absorptive notch. More precisely, the circuit introduces a fixed absorptive notch at 4.22 GHz and two electronically tunable (approximately 20%) conventional notches at 1.62–2 and 4.71–5.75 GHz, respectively. Besides, the FBWs of the first conventional notch, the second one, and the absorptive notch are 5.5 ± 1, 3.5 ± 1, and 3 ± 1%, respectively. The instantaneous surface current density of the circuit is depicted to investigate the generation of notches. The circuit has a compact size of 44.7 × 11.85 mm2 equaling to 0.489 × 0.129  ; moreover, it can successfully absorb more than 98% of the input power at its absorptive notch.
Proton resonance frequency‐based thermometry for aqueous and adipose tissues
Authors: Zong Shenyan , Shen Guofeng , Mei Chang‐Sheng
Published: September 2021

Purpose

The proton resonance frequency (PRF)‐based thermometry uses heating‐induced phase variations to reconstruct magnetic resonance (MR) temperature maps. However, the measurements of the phase differences may be corrupted by the presence of fat due to its phase being insensitive to heat. The work aims to reconstruct the PRF‐based temperature maps for tissues containing fat.

Methods

This work proposes a PRF‐based method that eliminates the fat's phase contribution by estimating the temperature‐insensitive fat vector. A vector in a complex domain represents a given voxel's magnetization from an acquired, complex MR image. In this method, a circle was fit to a time series of vectors acquired from a heated region during a heating experiment. The circle center served as the fat vector, which was then subtracted from the acquired vectors, leaving only the temperature‐sensitive vectors for thermal mapping. This work was verified with the gel phantoms of 10%, 15%, and 20% fat content and the ex vivo phantom of porcine abdomen tissue during water‐bath heating. It was also tested with an ex vivo porcine tissue during focused ultrasound (FUS) heating.

Results

A good agreement was found between the temperature measurements obtained from the proposed method and the optical fiber temperature probe in the verification experiments. In the gel phantoms, the linear regression provided a slope of 0.992 and an R2 of 0.994. The Bland–Altman analysis gave a bias of 0.49°C and a 95% confidence interval of ±1.60°C. In the ex vivo tissue, the results of the linear regression and Bland–Altman methods provided a slope of 0.979, an intercept of 0.353, an R2 of 0.947, and a 95% confidence interval of ±3.26°C with a bias of −0.14°C. In FUS tests, a temperature discrepancy of up to 28% was observed between the proposed and conventional PRF methods in ex vivo tissues containing fat.

Conclusions

The proposed PRF‐based method can improve the accuracy of the temperature measurements in tissues with fat, such as breast, abdomen, prostate, and bone marrow.
Synthetische Kraftstoffe: Oxygenat‐Verbindungen
Authors: Kundler Isabel
Published: September 2021

Auf der Fährte des Treibstoffs der Zukunft untersucht ein Projekt Dimethylcarbonat, Methylformiat und Oxymethylenether für Diesel‐ beziehungsweise Ottomotoren. Die flüssigen chemischen Energieträger lassen sich klimaneutral herstellen.
Oxidationsprozesse in der Atmosphäre
Authors: Berndt Torsten
Published: September 2021

Der Abbau von Spurengasen in der Atmosphäre und Verbrennungsreaktionen verlaufen nach einem ähnlichen Prinzip. Dies zeigen Untersuchungen mit hochempfindlichen Methoden, die Vorgänge in der Natur im Labor nachbilden und mit denen sich Reaktionsketten massenspektrometrisch verfolgen lassen.
Elektromobilität und synthetische Kraftstoffe
Authors: Priester Denis , Krossing Ingo
Published: September 2021

Ein CO2‐neutraler Transportsektor ist mit erneuerbarem Strom realisierbar. Wie viel elektrische Energie dafür nötig ist, hängt von den verwendeten Antriebsformen ab. Daher sind CO2‐Ausstoß und Energiebedarf der zur Verfügung stehenden Techniken stets gemeinsam zu betrachten: ob batterieelektrisch, brennstoffzellenbetrieben oder mit E‐Fuels angetrieben.
Gut verpackt ist manchmal besser
Authors: Osterath Brigitte
Published: September 2021

Einkaufen, ohne sich hinterher durch Berge von Plastikmüll wühlen zu müssen − das wünschen sich immer mehr Verbraucher. Unverpacktläden liegen im Trend. 53 Prozent der Kunststoffabfälle in Deutschland, also 3,31 Millionen Tonnen, wurden im Jahr 2019 verbrannt und trugen so zu CO2‐Emissionen bei. Ob weniger Verpackung für die Umwelt besser ist, hängt allerdings vom Einzelfall ab. Insbesondere von der Frage, ob statt des Plastiks dann verdorbene Lebensmittel im Abfall landen.
Trendbericht Lebensmittelchemie
Authors: Hanschen Franziska S.
Published: September 2021

Die Abbauwege von Glucosinolaten in Kohlgemüsen beeinflussen nicht nur deren sensorische Qualität, sondern auch die Effekte auf die menschliche Gesundheit. Hierbei ist die Zubereitungsweise der Gemüse entscheidend. Die Abbaumechanismen der Glucosinolate traten in den letzten Jahren verstärkt in den Fokus der Forschung.
Psychometric evaluation of Nurse Professional Competence Scale—Short‐form Chinese language version among nursing graduate students
Authors: Xu Lijuan , Nilsson Jan , Zhang June , Engström Maria
Published: September 2021

Aim

The aim of the study was to determine the psychometric properties, construct validity and internal consistency of the Chinese language version of the Nurse Professional Competence scale short form.

Design

A methodological design was used.

Methods

Questionnaire data from 260 nursing students nearing graduation from 2 universities in China were analysed using confirmatory factor analysis, known‐group validity and internal consistency.

Results

The confirmatory factor analysis revealed that the model was acceptable, and the analyses for known‐group validity revealed statistically significant differences in all factors and the total scale of the Nurse Professional Competence scale short form. Internal consistency revealed that Cronbach's alpha values exceeded 0.70 for all factors and the total scale. The Chinese language version of the Nurse Professional Competence scale short form has acceptable construct validity and good internal consistency.
Algorithmic approaches to ostomy management: An integrative review
Authors: Heerschap Corey , Butt Britney
Published: September 2021

Objective

The aim of this review is to describe approaches to ostomy management utilizing algorithmic approaches found within the literature.

Design

An integrative review approach was used based on a modified Cooper's five‐stage research review framework.

Data Sources

Systematic searches occurred using the CINAHL and MEDLINE databases searching for peer‐reviewed, English publications.

Review Methods

There were 640 articles identified through the review process, 608 of which were excluded based on title and abstract review. The remaining 12 articles were assessed in full text after which two studies were removed as duplicates and six studies were excluded based on inclusion/exclusion criteria. Four studies were included in this synthesis. Studies were critically analysed using a critical appraisal tool developed for both qualitative and quantitative study assessments.

Results

Utilizing inductive content analysis, included literature was presented within two categories: validation of ostomy algorithms and implementation of ostomy algorithms in practice. Four themes emerged from these categories including the following: algorithm validation, identifying underlying causes, focus on accessories and large‐scale implementation.

Conclusion

No currently available validated algorithms published in full were found during this literature review. Current literature demonstrates the potential benefit for ostomy management algorithms to standardize and improve ostomy patient care.

Impact

This study sought to determine the availability and supporting research of ostomy management algorithms which may assist in standardizing and improving ostomy care. This review has demonstrated a lack of available ostomy management algorithms. Given the potential benefit of ostomy algorithms identified within the literature, further studies should be completed to develop, validate and test new ostomy management algorithms.
Causes of burnout syndrome and coping strategies among high dependency unit nurses of an institution in the greater Accra region of Ghana
Authors: Boateng Yaa Adomaah , Osei Sylvia Ama , Aboh Irene Korkoi , Druye Andrew Adyei
Published: September 2021

Aim

The aim of this study was to determine the causes of burnout syndrome and identify strategies to cope with them among nurses at high dependency unit if a regional Hospital in Ghana.

Design

A descriptive convenient and purposive cross‐sectional study design was used for this study.

Methods

The study involved 40 nurses in the high dependency unit of the Hospital. A Maslach Burnout Inventory (MBI) was adopted to measure burnout experienced by these nurses concentrating on feelings of being emotionally exhausted and lack of energy, depersonalization, feelings of impersonal response towards patients and personal achievement.

Results

62.5% of the respondents were in the high emotional exhaustion, 55% scored high in the depersonalization section and 52.5% scored high in the personal achievement (competence) on the Maslach Burnout Inventory (MBI).
Eight‐week exercise training in humans with obesity: Marked improvements in insulin sensitivity and modest changes in gut microbiome
Authors: Verheggen Rebecca J. H. M. , Konstanti Prokopis , Smidt Hauke , Hermus Ad R. M. M. , Thijssen Dick H. J. , Hopman Maria T. E.
Published: September 2021

Objective

Obesity is associated with impaired gut microbiota diversity, which has been linked to the development of type 2 diabetes. This study aims to examine the effects of an 8‐week aerobic exercise intervention on insulin sensitivity, visceral adiposity, and gut microbiota diversity and composition in participants with obesity.

Methods

Fourteen participants (mean [SD], age 51 [11] years; BMI 34.9 [4.9] kg/m2) performed an 8‐week exercise intervention (2 to 4 times/week on 65% to 85% of heart rate reserve). Insulin sensitivity (hyperinsulemic euglycemic clamp), cardiorespiratory fitness (maximal oxygen uptake), visceral adiposity (dual‐energy X‐ray absorptiometry scan) and gut microbiota composition (16S rRNA gene sequencing) were measured before and after the intervention.

Results

Insulin sensitivity showed a significant increase (pre: 3.8 [1.9] mg/min/kg; post: 4.5 [1.7] mg/min/kg; p = 0.007) after training, whereas visceral adiposity decreased (pre: 959 [361] cm3; post: 897 [364] cm3; p = 0.02). No change in gut microbiota α‐ or β‐diversity was found. At the genus level, the abundance of Ruminococcus gauvreauii (p = 0.02); Lachnospiraceae FCS020 group (p = 0.04), and Anaerostipes (p = 0.04) significantly increased after exercise training. Significant positive correlations were present for M‐value (R. gauvreauii) and VO2 max (R. gauvreauii and Anaerostipes).

Conclusions

Eight‐week exercise training in humans with obesity leads to marked improvements in insulin sensitivity and body composition and is accompanied by modest changes in 3 gut microbiome genera, all belonging to the Firmicutes phylum.
COVID‐19 pandemic and stay‐at‐home mandates promote weight gain in US adults
Authors: Seal Adam , Schaffner Andrew , Phelan Suzanne , Brunner‐Gaydos Hannah , Tseng Marilyn , Keadle Sarah , Alber Julia , Kiteck Isabelle , Hagobian Todd
Published: September 2021

Objective

The purpose of this study was to prospectively examine the effect of state stay‐at‐home mandates on weight of US adults by BMI over 3 months during COVID‐19.

Methods

US adults completed an online questionnaire containing demographics, weight, physical activity, sedentary time, fruit/vegetable intake, depressive symptoms, stress, and sleep at baseline (May 2020) and after 3 months (August 2020).

Results

Participants gained 0.6 kg (76.7‐77.3 kg, p = 0.002). A total of 26% of those with obesity gained > 2 kg compared with 14.8% of those with normal weight (p < 0.001). A total of 53.3% of individuals with obesity maintained weight within 2 kg compared with 72.5% of those with normal weight (p < 0.001). Greater weight gain was related to longer stay‐at‐home mandates (β = 0.078, p = 0.010), lower baseline minutes of physical activity per day (β = −0.107, p = 0.004), greater declines in minutes of physical activity per day (β = −0.076, p = 0.026), depressive symptoms (β = 0.098, p = 0.034), and greater increases in time preparing food (β = 0.075, p = 0.031).

Conclusions

US adults gained weight, and stay‐at‐home mandates were associated with atypical weight gain and greater reported weight gain in individuals with obesity over 3 months.
The Kids on the Bus: The Academic Consequences of Diversity‐Driven School Reassignments
Authors: Domina Thurston , Carlson Deven , Carter James , Lenard Matthew , McEachin Andrew , Perera Rachel
Published: September 2021

Many public school diversity efforts rely on reassigning students from one school to another. While opponents of such efforts articulate concerns about the consequences of reassignments for students’ educational experiences, little evidence exists regarding these effects, particularly in contemporary policy contexts. Using an event study design, we leverage data from an innovative socioeconomic school desegregation plan to estimate the effects of reassignment on reassigned students’ achievement, attendance, and exposure to exclusionary discipline. Between 2000 and 2010, North Carolina's Wake County Public School System (WCPSS) reassigned approximately 25 percent of students with the goal of creating socioeconomically diverse schools. Although WCPSS's controlled school choice policy provided opportunities for reassigned students to opt out of their newly reassigned schools, our analysis indicates that reassigned students typically attended their newly reassigned schools. We find that reassignment modestly boosts reassigned students’ math achievement, reduces reassigned students’ rate of suspension, and has no offsetting negative consequences on other outcomes. Exploratory analyses suggest that the effects of reassignment do not meaningfully vary by student characteristics or school choice decisions. The results suggest that carefully designed school assignment policies can improve school diversity without imposing academic or disciplinary costs on reassigned students.
Cardiac‐specific deletion of FDPS induces cardiac remodeling and dysfunction by enhancing the activity of small GTP‐binding proteins
Authors: Wang Xiying , Zhang Xuan , Chen Yuxiao , Zhao Chenze , Zhou Weier , Chen Wanwan , Zhang Chi , Ding Kejun , Li Weidong , Xu Hongfei , Lou Lian , Chu Zhenliang , Hu ShenJiang , Yang Jian
Published: September 2021

The mevalonate pathway is essential for cholesterol biosynthesis. Previous studies have suggested that the key enzyme in this pathway, farnesyl diphosphate synthase (FDPS), regulates the cardiovascular system. We used human samples and mice that were deficient in cardiac FDPS (c‐Fdps−/− mice) to investigate the role of FDPS in cardiac homeostasis. Cardiac function was assessed using echocardiography. Left ventricles were examined and tested for histological and molecular markers of cardiac remodeling. Our results showed that FDPS levels were downregulated in samples from patients with cardiomyopathy. Furthermore, c‐Fdps−/− mice exhibited cardiac remodeling and dysfunction. This dysfunction was associated with abnormal activation of Ras and Rheb, which may be due to the accumulation of geranyl pyrophosphate. Activation of Ras and Rheb stimulated downstream mTOR and ERK pathways. Moreover, administration of farnesyltransferase inhibitors attenuated cardiac remodeling and dysfunction in c‐Fdps−/− mice. These results indicate that FDPS plays an important role in cardiac homeostasis. Deletion of FDPS stimulates the downstream mTOR and ERK signaling pathways, resulting in cardiac remodeling and dysfunction. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Impact of COVID‐19 pandemic on a large cohort of adult survivors of childhood cancer
Authors: Krull Kevin R. , McDonald Aaron , Goodman Pamela , Vukadinovich Christopher , Ford James , Leisenring Wendy M. , Chow Eric J. , Robison Leslie L. , Armstrong Gregory T.
Published: September 2021

Childhood cancersurvivors may be differentially impacted by coronavirus disease 2019 (COVID‐19). From April to June of 2020, we examined psychosocial/health concerns in 4148 adult survivors and 571 siblings. Although more survivors reported concerns about getting sick (p = .002) and needing hospitalization (p = .003) in general, survivors and siblings were comparably concerned about being infected with and the consequences of COVID‐19. Cranial radiation was associated with social isolation (relative risk [RR] = 1.3, CI = 1.1–1.7), and central nervous system (CNS) tumors were associated with unemployment due to COVID‐19 (RR = 1.7, CI = 1.2–2.2). Some survivors appear more vulnerable and may require more support to meet health care and vocational needs during COVID‐19, though siblings also perceive substantial risk.
Revealing the effect of oligo(ethylene glycol) side chains on n‐doping process in FBDPPV‐based polymers
Authors: Wang Xin‐Yi , Liu Yi , Wang Zi‐Yuan , Lu Yang , Yao Ze‐Fan , Ding Yi‐Fan , Yu Zi‐Di , Wang Jie‐Yu , Pei Jian
Published: September 2021

The low doping efficiency of n‐doped systems limits the development of n‐type organic conducting materials. Oligo(ethylene glycol) (OEG) as the flexible chain in conjugated small molecules and polymers may improve doping efficiency. However, OEG side chains also bring unexpected low mobility and poor film morphology. Herein, we propose the stronger solution‐state aggregation plays a dominated role in charge transport and morphology of OEG‐substituted polymer. The solution‐state aggregation also affects doping process. Therefore, we develop a series of polymers based on 3,7‐bis((E)‐7‐fluoro‐1‐(2‐octyldodecyl)‐2‐oxoindolin‐3‐ylidene)‐3,7‐dihydrobenzo[1,2‐b:4,5‐b']difuran‐2,6‐dione (FBDPPV) with different ratios of OEG side chain to investigate the effect of side chain on solution‐state aggregation and n‐doping process. After n‐doped by hexahydro‐1H,3a1H,4H,7H‐3a,6a,9a‐triazaphenalene (TAM), FBDPPV with 50% OEG affords the highest doping efficiency and conductivity, while FBDPPV with 100% OEG shows lower conductivity. Combination of ultraviolet–visible–near infrared absorption spectra, grazing‐incidence wide‐angle X‐ray scattering and atomic force microscopy, we reveal that serious aggregated extent in solution of OEG‐substituted polymer result in phase separation and rough morphology, which are the origins of poor conductivity. Our work provides a new perspective on the effect of the OEG side chain on the doped polymer systems, suggesting suitable solution‐state aggregation is crucial to high doping efficiency and high conductivity.