bluuebunny/crossref_metadata_2025 huggingface dataset:
Return on Investment in Model‐Based Systems Engineering Software Tools
Authors: Duffy James B. , Feng Jingyao , Combs Robert , Richardson James P.
Published: September 2021

This research paper describes a means of determining the return (benefits, or value) of an organization's investments in software tools to support their system engineering activities. The research considers a range of organizational attributes, including size of the system engineering labor force, type of engineering activities which must be performed, the level of difficulty of the activities and organizational objectives. The research considers three categories of software tools, starting with a benchmark of Microsoft Office products, and including modern SysML and LML engineering tools. The research develops a model of financial metrics based on the capabilities of each tool, its costs, and the engineering processes to which it can be applied. The research finds that considerable organization returns are realized with investments in such tools, most significantly the reduction in engineering labor needed to perform engineering tasks. Additional returns can be expected in terms of engineering project performance (success) and in the ability of an organization to pursue larger or more challenging engineering projects.
The Evolution of HELIX: A Competency Model for Complex Problem Solving
Authors: McDermott Tom , Hutchison Nicole , Crick Ruth
Published: September 2021

Today's systems are continuing to increase in complexity, and employers have placed a premium on critical and systems thinking skills. The World Economic Forum (WEF) reports that an increasing share of jobs are focused more heavily on soft skills or a combination of soft and technical skills. The WEF 5‐year survey of most desired job skills highlight the growing focus on the cognitive and relationship‐building aspects of the future workspace. “Complex Problem Solving” has topped the list in both the 2015 and 2020 reports. This paper consolidates and proposes a common framework for lifelong learning in the engineering domain, targeted at practical tools that help engineers solve complex problems, think and learn more holistically, and apply that learning to team leadership. Although the work has been focused on engineering roles, it may be generally applied to any domain where complex problem solving is at a premium. The framework identifies five complex problem‐solving competency sets: sensemaking, adaptive and computational thinking, a design mindset, system architecting and communicating, and leading teams through cycles of learning. These competencies are developed through the experience of a learning infrastructure which integrates learning with the work do be done, through facilitating learning and performance in systems thinking, team leadership and personal learning power and self‐leadership. This paper presents the framework, the background research that led to its development, and how it might be delivered through teaching and mentoring on complex projects.
A Guide for Systems Engineers to Finding Your Role in 21st‐Century Software‐Dominant Organizations
Authors: Sheard Sarah , Bouyaud Mickael , Osaisai Macaulay , Siviy Jeannine , Nidiffer Kenneth E.
Published: September 2021

The decision makers in many software‐dominant organizations, such as the FAANGs (Facebook, Apple, Amazon, Netflix, and Google), evolved quickly from coders and software engineers unfamiliar with the advantage of the big‐picture view of the software and of the organizations developing the software. INCOSE's Systems and Software Interface Working Group (SaSIWG) has been reading a fable of such an organization that found itself in a typical terrible state, unable to respond quickly and effectively to customer needs, because it was tied up in a complex mess of silos, dependencies, management rules, and blame. While the book has garnered praise as the answer to many software organizations’ problems, it quite significantly omits any mention of systems engineering as well as much positive mention of architecture or project management.

In response, the SaSIWG has been working on a set of tools to help first ourselves and then INCOSE systems engineers understand several important aspects of such organizations. First, how do such systems engineering‐deficient organizations work? Second, what does their terminology mean at a top level, in a way that doesn't take a computer science degree to understand or a day to look up? Third, how can a systems engineer break into the software engineering conversation and leave it without feeling defeated and overwhelmed by the unfamiliar jargon, but rather knowing they can be and have been useful? Finally, how can systems engineers plan in the long run to assist in engineering the complex system that is the software development enterprise and ecosystem? This is not always acknowledged as a system needing engineering, but it is universally acknowledged as “the problem” when it is not well engineered.

This paper provides an overview of the tools that are being developed and outlines the guide that the group is hoping to create.
Technical Leadership of Virtual and Remotely Distributed Teams
Authors: Dazzi Francesco , McKelvin Mark , Gallego Elena , McCoy Sean , Keen W. Patrick , Weigel Allison , Ziliox Lisa
Published: September 2021

The world is increasingly virtual and complex, with many relationships and teams at a global scale. The situation will not be changing any time soon. Sometimes, it is only possible to interact at a distance, of not only time zones and space, but also sometimes interpersonal distance, where names and voices make up another person. Regardless, technical teams will need good leadership to address complex situations in these virtual and remotely distributed (VaRD) environments. So, in a VaRD environment, do leadership practices and skills have to change? Do the tools, techniques, and technology make current practices for leadership in general, and the application of those practices obsolete? Maybe not.

This paper seeks to examine the nature of what is really changing when leading in a VaRD environment through the lens of engineers leading teams in global and complex technical challenges. Those perspectives are analyzed to determine the factors that go into a VaRD environment. In addition, this paper analyzes how interactions between teams compare to an in‐person environment, how leadership practices are applied in this environment, and how technical leadership is tailored for these new environments.
Workforce and Evaluation and Training for Digital Engineering in the US Department of Defense
Authors: Hutchison Nicole , Tao Hoong Yan See , Pepe Kara , Blackburn Mark , Verma Dinesh , Peak Russell , Baker Adam , Whitcomb Clifford , Khan Rabia
Published: September 2021

Digital engineering (DE) is “an integrated digital approach that uses authoritative sources of systems’ data and models as a continuum across disciplines to support lifecycle activities from concept through disposal. A DE ecosystem is an interconnected infrastructure, environment, and methodology that enables the exchange of digital artifacts from an authoritative source of truth.” (DAU, 2017) Digital transformation is fundamentally changing the way acquisition and engineering are performed across a wide range of government agencies, industries, and academia and is characterized by the integration of digital technology into all areas of a business, changing fundamental operations and how results are delivered in terms of new value to customers. It includes cultural change centered on alignment across leadership, strategy, customers, operations, and workforce evolution. In 2020, the Systems Engineering Research Center (SERC) developed a Digital Engineering Competency Framework (DECF) to support the US Department of Defense (DoD). This paper provides an update to the DECF (version. 1.1) and a mapping of some existing DoD training resources against the DECF. It discusses gaps and provides a few high‐level recommendations on how to build DE competency in the DoD acquisition workforce. Though the DECF and the training included here are specific to the DoD, the competency framework is intended to be relevant to anyone working in the DE space.
Using Digital Viewpoint Concept Model for Defining Digital Engineering Information Exchange
Authors: McGervery Sean , Tseng Celia , Hambrick Tamara
Published: September 2021

The objective of the DVM concept model is to characterize the content and relationships involved in the exchange of digital artifacts and its curation for stakeholder use and consumption. The Digital Engineering Information Exchange Working Group (DEIX WG) developed this concept model to describe the interactions and challenges of exchanging a diverse set of information in a digital environment. The DEIX WG is a collaboration between the International Council of Systems Engineers (INCOSE), the National Defense Industry Association (NDIA) Modeling and Simulation (M&S) Subcommittee, and the Department of Defense, Office of the Under Secretary for Research and Engineering (DoD/OUSE (R&E)). The DEIX WG supports the strategic objective to accelerate the digital engineering transformation by evolving the characterization of the content and relationships involved in the exchange of digital artifacts between disciplines and stakeholders throughout the engineering lifecycle.
Molecular weight determination of adeno‐associate virus serotype 8 virus‐like particle either carrying or lacking genome via native nES gas‐phase electrophoretic molecular mobility analysis and nESI QRTOF mass spectrometry
Authors: Zoratto Samuele , Weiss Victor U. , van der Horst Jerre , Commandeur Jan , Buengener Carsten , Foettinger‐Vacha Alexandra , Pletzenauer Robert , Graninger Michael , Allmaier Guenter
Published: September 2021

Virus‐like particles (VLPs) are proteinaceous shells derived from viruses lacking any viral genomic material. Adeno‐associated virus (AAV) is a non‐enveloped icosahedral virus used as VLP delivery system in gene therapy (GT). Its success as vehicle for GT is due to its selective tropism, high level of transduction, and low immunogenicity. In this study, two preparations of AAV serotype 8 (AAV8) VLPs either carrying or lacking completely genomic cargo (i.e., non‐viral ssDNA) have been investigated by means of a native nano‐electrospray gas‐phase electrophoretic mobility molecular analyzer (GEMMA) (native nES GEMMA) and native nano‐electrospray ionization quadrupole reflectron time‐of‐flight mass spectrometry (MS) (native nESI QRTOF MS). nES GEMMA is based on electrophoretic mobility principles: single‐charge nanoparticles (NPs), that is, AAV8 particle, are separated in a laminar sheath flow of dry, particle‐free air and a tunable orthogonal electric field. Thus, the electrophoretic mobility diameter (EMD) of a bio‐NP (i.e., diameter of globular nano‐objects) is obtained at atmospheric pressure, which can be converted into its MW based on a correlation. First is the native nESI QRTOF. MS's goal is to keep the native biological conformation of an analyte during the passage into the vacuum. Subsequently, highly accurate MW values are obtained from multiple‐charged species after deconvolution. However, once applied to the analysis of megadalton species, native MS is challenging and requires customized instrumental modifications not readily available on standard devices. Hence, the analysis of AAV8 VLPs via native MS in our hands did not produce a defined charge state assignment, that is, charge deconvolution for exact MW determination was not possible. Nonetheless, the method we present is capable to estimate the MW of VLPs by combining the results from native nES GEMMA and native ESI QRTOF MS. In detail, our findings show a MW of 3.7 and 5.0 MDa for AAV8 VLPs either lacking or carrying an engineered genome, respectively.
Stepwise‐clustered heatwave downscaling and projection for Guangdong Province
Authors: Ren Jiayan , Huang Guohe , Li Yongping , Zhou Xiong , Lu Chen , Duan Ruixin
Published: September 2021

Heatwave events over Guangdong have attracted recent attention under changing climate conditions. It is desired to explore the future changes of heatwave due to its associated consequences on society economy and environment. In this study, a stepwise‐clustered heatwave downscaling approach (i.e., SCHW) was developed for the projection of HWs in Guangdong. The heatwave indicators (occurrence, duration, magnitude, intensity, frequency, and accumulated intensity) were investigated from both the absolute and relative definitions of heatwave events (i.e., AHWs and RHWs) based on the multi‐model ensemble of 13 coupled model intercomparison projected phase 5 (CMIP5) global climate models (GCMs) under two representative concentration pathways (RCPs). The trends (i.e., 0.18–0.29°C per decade under RCP4.5 and 0.30–0.58°C per decade under RCP8.5) of the projected daily maximum temperature indicate that Guangdong would experience continuous warming in the future. The occurrence, frequency, and accumulated intensity of heatwave would increase by 198%, 272%, and 346% in the 2080s (i.e., 2066–2095) under RCP8.5 compared to the historical period (i.e., 1976–2005), respectively. Moreover, the three indicators of HWs are projected to have more substantial increases over inland Guangdong than its costal parts. The spatial variation of occurrence of absolute and relative heatwave under RCP8.5 (2.80 and 2.78) is larger than these under RCP4.5 (2.50 and 2.32) during 2080s (i.e., 2066–2095). The projections of future HWs can help provide valuable information for assessing extreme climate change and identifying desired adaptation strategies.
Spatial 3D mapping of forest soil carbon stocks in Hesse, Germany
Authors: Heitkamp Felix , Ahrends Bernd , Evers Jan , Meesenburg Henning
Published: September 2021

Background

Forest soils are an important reservoir of organic carbon (OC) and a potential source or sink for atmospheric CO2. Prediction of OC stock changes under ongoing climatic and management changes requires a spatial explicit base. Knowledge of the vertical distribution of OC stocks is very important, since varying soil layers may be affected differently by environmental change.

Aim

Three‐dimensional regionalization of OC stocks of the forest floor (FFC) and 5 cm depth increments of the mineral soil (SOC) of Hesse, Germany.

Methods

Datasets of the second National Forest Soil Inventory (NFSI II) were used for parametrization of hierarchical generalized additive models (hGAM). Validation was performed by a 10 times repeated 10‐fold cross‐validation, and spatial model uncertainty was assessed.

Results

Depth‐dependent validation indicated that model performance was best between 15 and 60 cm (amount of variance explained ≈ 0.5). All covariates showed plausible partial effects. FFC stocks were predicted to be highest under coniferous forest with a high influence of N deposition. Climate and potential cation exchange capacity affected SOC stocks markedly, whereas soil class and parent material were most important for the depth distribution. Overall, average predicted OC stocks were between 78.0 and 92.5 t ha−1, amounting to 67.6 to 80.1 Mt for all forest soils of Hesse. Between 16% and 24% were stored in the forest floor. Sixty‐eight percent to 69% of predicted SOC stocks were stored in the upper 30 cm. Model uncertainty was highest at locations with high elevation or ground water influence.

Conclusions

This work provides the first spatial explicit database for OC stocks of forest soils in Hesse at an intermediate scale. Stocks can be assessed flexibly for varying depth from the forest floor down to 100 cm. Uncertainty analysis informs about locations, where the model results have to be handled with care.
Radical scavenging behavior of butylated hydroxytoluene against oxygenated free radicals in physiological environments: Insights from DFT calculations
Authors: Boulebd Houssem
Published: September 2021

Butylated hydroxytoluene (BHT) is a synthetic antioxidant widely used as a preservative in foods containing fat, the petroleum industry, and pharmaceuticals. Herein, a systematic investigation of reaction mechanisms and kinetics of BHT initiated by HO• and HOO• radicals in physiological environments has been reported for the first time. The overall rate coefficients were determined according to the QM‐ORSA (quantum mechanics‐based test for overall free radical scavenging activity) procedure at the M06‐2X/6‐311++G(d,p) level of theory. The radical adduct formation has been found to be the decisive mechanism for HO• scavenging in both polar and lipid media with koverall = 1.39 × 1012 and 1.13 × 1011 M–1 s–1, respectively. While this mechanism has no contribution to HOO• scavenging in physiological environments which mainly takes place via the hydrogen atom transfer mechanism (koverall = 2.51 × 105 and 1.70 × 104 M–1 s–1 in water and lipid media, respectively). The obtained findings are consistent with the available experimental data, which validates the accuracy of the calculations.
Benefits of Cochlear Implantation in Childhood Unilateral Hearing Loss (CUHL Trial)
Authors: Brown Kevin D. , Dillon Margaret T. , Park Lisa R.
Published: September 2021

Objectives/Hypotheses

Children with unilateral sensory hearing loss (UHL) struggle to understand speech in noise and locate the origin of sound and have reduced quality of hearing. This clinical trial will determine the benefits of cochlear implantation in children with UHL.

Study Design

Prospective clinical trial.

Methods

Twenty children with at least moderate to profound sensory hearing loss and poor speech perception (word score <30%) in one ear and normal hearing in the contralateral ear participated in a Food and Drug Administration‐approved clinical trial. Subjects were evaluated for speech perception in quiet, speech perception in noise, sound localization, and subjective benefits after implantation.

Results

CNC word score perception in quiet significantly improved (1% to 50%, P < .0001) by 12 months after activation. Speech perception in noise by BKB‐SIN significantly improved in all three noise configurations; there was a 3.6 dB advantage in head shadow (P < .0001), a 1.6 dB advantage in summation (P = .003), and a 2.5 dB advantage in squelch (P = .0001). Localization improved by 26° at 9 months (P < .0001). Speech, Spatial, and Qualities (SSQ) demonstrated significant improvements in speech (5.2 to 7.4, P = .0012), qualities of hearing (5.9 to 7.5, P = .0056), and spatial hearing (2.7 to 6.6, P < .0001). SSQ subscales associated with binaural hearing were significantly improved, as was listening effort (P = .0082). Subjects demonstrated a non‐significant improvement in fatigue.

Conclusions

This study demonstrates that children with UHL significantly benefit from cochlear implantation.

Level of Evidence

Level 3 Laryngoscope, 132:S1–S18, 2022
Evaluation of hyperspectral imaging to quantify perfusion changes during the modified Allen test
Authors: Linek Matthäus , Felicio‐Briegel Axelle , Freymüller Christian , Rühm Adrian , Englhard Anna Sophie , Sroka Ronald , Volgger Veronika
Published: September 2021

Objectives

To evaluate the capability of hyperspectral imaging (HSI), a contact‐less and noninvasive technology, to monitor perfusion changes of the hand during a modified Allen test (MAT) and cuff occlusion test. Furthermore, the study aimed at obtaining objective perfusion parameters of the hand.

Methods

HSI of the hand was performed on 20 healthy volunteers with a commercially available HSI system during a MAT and a cuff occlusion test. Besides gathering red‐green‐blue (RGB) images, the perfusion parameters tissue hemoglobin index (THI), (superficial tissue) hemoglobin oxygenation (StO2), near‐infrared perfusion (NIR), and tissue water index (TWI) were calculated for four different regions of interest on the hand. For the MAT, occlusion (OI; the ratio between the condition during occlusion and before occlusion) and reperfusion (RI; the ratio between the non‐occlusion state and the prior occlusion state) indices were calculated for each perfusion parameter. All data were correlated to the clinical findings.

Results

False‐color images showed visible differences between the various perfusion conditions during the MAT and cuff occlusion test. THI, StO2, and NIR behaved as expected from physiology, while TWI did not in the context of this study. During rest, mean THI, StO2, and NIR of the hand were 34 ± 2, 72 ± 9, and 61 ± 6, respectively. The RI for THI showed a roundabout threefold increase after reperfusion of both radial and ulnar artery and was thus, distinctly pronounced when compared with StO2 and NIR (~1.25). The OI was lowest for THI when compared with StO2 and NIR.

Conclusions

HSI with its parameters THI, StO2, and NIR proved to be suitable to evaluate perfusion of the hand. By this, it could complement visual inspection during the MAT for evaluating the functionality of the superficial palmary arch before radial or ulnar artery harvest. The presented RI might deliver useful comparative values to detect pathological perfusion disorders at an early stage. As microcirculation monitoring is crucial for many medical issues, HSI shows potential to be used, besides further applications, in the monitoring of (free) flaps and transplants and microcirculation monitoring of critically ill patients.
Corrosion properties of Ti3SiC2 and Ti3AlC2 in static liquid lead–bismuth eutectic at 500°C
Authors: Zhu Huiping , Liu Xudong , Chang Baochen , Li Xiaobo , Qi Muran , Wang Yifeng , Niu Fenglei , Ma Yan , Lyu Liangliang
Published: September 2021

For lead‐cooled fast reactors and accelerator‐driven subcritical systems, the surface corrosion behavior of candidate structural materials in lead–bismuth eutectic (LBE) is a key issue, which determines whether the material is applicable. The candidate materials of two typical MAX phases, Ti3SiC2 and Ti3AlC2, were immersed in static LBE with saturated oxygen concentration at 500°C for up to 3000 h. The corrosion behaviors of Ti3SiC2 and Ti3AlC2 were analyzed by scanning electron microscope, energy‐dispersive X‐ray, X‐ray diffraction, and Raman spectra. The experimental results showed that elements interdiffusion between LBE and sample matrix occurred on both Ti3SiC2 and Ti3AlC2 surfaces, which led to the formation of the diffusion layer. The dominant component of the diffusion layer is PbTiO3, which makes the corroded surface fragile in a stress environment. Besides, there were differences in structures of corroded sample surfaces between Ti3SiC2 and Ti3AlC2. The corrosion layer of Ti3SiC2 consisted of two layers, while only one single layer formed on Ti3AlC2 surfaces. The stable oxide layer consisting of SiO2 and TiO2 can protect Ti3SiC2 samples from further LBE corrosion and maintain the integrity of the surfaces. For Ti3AlC2 samples, it is hard to form a continuous Al2O3 protective layer, thus no stable oxide layer was detected on the corroded surfaces. Compared with Ti3AlC2, Ti3SiC2 showed better corrosion resistance in LBE.
Thermoplastic Polyamide Elastomers: Synthesis, Structures/Properties, and Applications
Authors: Gong Shun , Zhao Shikun , Chen Xiangyang , Liu Huipeng , Deng Jianping , Li Suyuan , Feng Xinxing , Li Yucai , Wu Xin , Pan Kai
Published: September 2021

Thermoplastic polyamide elastomers (TPAEs) have emerged as important thermoplastic elastomer materials with significant potentials owing to their excellent low‐temperature flexibility, easy processability, lightweight, good thermal stability and mechanical properties, etc. Over the last few decades, TPAEs have rapidly developed into a large variety of kinds of TPAEs. Striking advancements have been achieved in this research field. Unfortunately, there is not yet a review to summarize the progress. The present paper summarizes the major advancements dealing with TPAEs, in which synthesis, structures/properties as well as applications are introduced in detail. Moreover, current challenges and main developmental directions dealing with TPAEs are also presented. This review may motivate more interest in TPAEs, further facilitating their all‐side research and more large‐scale applications.
Simultaneous image reconstruction and lesion segmentation in accelerated MRI using multitasking learning
Authors: Sui Bin , Lv Jun , Tong Xiangrong , Li Yan , Wang Chengyan
Published: September 2021

Purpose

Magnetic resonance imaging (MRI) serves as an important medical imaging modality for a variety of clinical applications. However, the problem of long imaging time limited its wide usage. In addition, prolonged scan time will cause discomfort to the patient, leading to severe image artifacts. On the other hand, manually lesion segmentation is time consuming. Algorithm‐based automatic lesion segmentation is still challenging, especially for accelerated imaging with low quality.

Methods

In this paper, we proposed a multitask learning‐based method to perform image reconstruction and lesion segmentation simultaneously, called “RecSeg”. Our hypothesis is that both tasks can benefit from the usage of the proposed combined model. In the experiment, we validated the proposed multitask model on MR k‐space data with different acceleration factors (2×, 4×, and 6×). Two connected U‐nets were used for the tasks of liver and renal image reconstruction and segmentation. A total of 50 healthy subjects and 100 patients with hepatocellular carcinoma were included for training and testing. For the segmentation part, we use healthy subjects to verify organ segmentation, and hepatocellular carcinoma patients to verify lesion segmentation. The organs and lesions were manually contoured by an experienced radiologist.

Results

Experimental results show that the proposed RecSeg yielded the highest PSNR (RecSeg: 32.39 ± 1.64 vs. KSVD: 29.53 ± 2.74 and single U‐net: 31.18 ± 1.68, respectively, p < 0.05) and highest structural similarity index measure (SSIM) (RecSeg: 0.93 ± 0.01 vs. KSVD: 0.88 ± 0.02 and single U‐net: 0.90 ± 0.01, respectively, p < 0.05) under 6× acceleration. Moreover, in the task of lesion segmentation, it is proposed that RecSeg produced the highest Dice score (RecSeg: 0.86 ± 0.01 vs. KSVD: 0.82 ± 0.01 and single U‐net: 0.84 ± 0.01, respectively, p < 0.05).

Conclusions

This study focused on the simultaneous reconstruction of medical images and the segmentation of organs and lesions. It is observed that the multitask learning‐based method can improve performances of both image reconstruction and lesion segmentation.
Superposition‐based concurrent multiscale approaches for poromechanics
Authors: Sun Wei , Fish Jacob , Ni Pengpeng
Published: September 2021

Superposition‐based concurrent multiscale approaches for poromechanical problems aimed at resolving localized fluid flow and deformation of a solid skeleton including its possible fracture are developed. The main departure of the proposed formulation is that the primary unknowns in the coupling zone, the solid displacement u and pore pressure p, are discretized by possibly different numerical models. Two discretization schemes are studied: (i) superposition of two or more finite element (FE) discretizations of the Biot's u‐p model of a porous medium, and (ii) superposition of the peridynamics (PD) discretization of the fractured solid phase on the FE discretization of the Biot's u‐p model of a porous medium. In the latter case, the total stress of the fluid–solid mixture in the coupling domain is derived from the effective stress obtained from the combined PD and finite element method solutions while the pore pressure is obtained from the FE solution. The accuracy of the superposition‐based concurrent multiscale method is studied on several benchmark problems including the classical Terzaghi's one‐dimensional consolidation problem, the two‐dimensional strip footing problem, and the pressure‐ and fluid‐driven fracture propagation problem in saturated porous media. The main hydraulic fracture characteristics, including complex crack paths and fluid flow patterns, have been found to be reasonably well reproduced by the proposed method.
Facile regulation of the electro‐optical properties of liquid crystal gels by kinetics‐controlled hierarchy self‐assembly
Authors: Shan Tianyu , Zheng Kai , Du Qinqing , He Huiwen , Shi Yanqin , Ma Meng , Chen Si , Wang Xu
Published: September 2021

Liquid crystal gels, exhibiting promising applications in novel light scattering displays, face the problem of the inherent contradiction between the applied voltage and the contrast, which are the two most basic and crucial parameters for displays. Regretfully, improvement of the applied voltage always means the sacrifice of contrast and vice versa, related to the morphology of the gel fibers. Alternatively, we propose an approach to easily regulate the electro‐optical properties to meet the needs of different applications, towards either lower applied voltage or higher contrast, based on kinetics‐controlled hierarchy self‐assembly. Thin rod‐like and thick helical gel fibers are formed when cooling the liquid crystal gel in water and air respectively, leading to significantly different electro‐optical properties. This method not only facilitates the large‐scale manufacture and application of light scattering displays, but also provides a practical application using the newly developed theory of kinetics‐controlled self‐assembly. © 2021 Society of Chemical Industry
Investigating the impact of regiochemistry in ester functionalized polyfurans
Authors: Varni Anthony J. , Kawakami Manami , Kramer Stephanie N. , Rice Megan , Geib Steven J. , Peteanu Linda A. , Kowalewski Tomasz , Noonan Kevin J. T.
Published: September 2021

In this study, the impact of ester side group regiochemistry on electronic and conformational properties of regioregular polyfurans was explored. A derivative with alternating head‐to‐head and tail‐to‐tail orientation of the side groups was synthesized and compared with its head‐to‐tail analogue, and these were benchmarked against the related regioregular poly(3‐hexylfurans). The study revealed that alkyl ester side groups in a head‐to‐head orientation will create significant steric strain as compared with linear alkyl chains with identical regiochemistry. Though the head‐to‐head ester side groups lead to twisting along the polymer backbone, they also produce a protective effect against photodegradation in comparison with a poly(3‐hexylfuran). Altogether, the work highlights how side groups can impact conformational properties and stability of polyfurans.
Mechanically versatile isosorbide‐based thermoplastic copolyether‐esters with a poly(ethylene glycol) soft segment
Authors: Monnery Bryn D. , Karanastasis Apostolos , Adriaensens Peter , Pitet Louis M.
Published: September 2021

Segmented thermoplastic copolyether esters (TPEE's) with a partially renewable hard block containing isosorbide (ISB) and poly(ethylene glycol) (PEG) soft blocks were prepared by melt polycondensation. A range of compositions was accessible despite the relatively low reactivity of the sterically and electronically hindered ISB monomer. The small‐scale reactions performed in the melt were limited in terms of achievable molar mass. This is attributed to the challenge of attaining stoichiometric balance in the feed and maintaining this balance throughout the high temperature (>200°C) reactions. Nevertheless, products were isolated that could be manipulated and melt‐pressed into specimen for tensile testing. Varying the feed compositions gave rise to copolymers exhibiting a broad range of mechanical properties (elastic modulus from 1–66 MPa). These characteristics are consistent with a segmented polymer architecture with morphological features similar to commercially available TPEE counterparts. These results pave the way for more responsibly sourced building blocks being incorporated into materials with high market value potential.
Thermally Evaporated Ag–Au Bimetallic Catalysts for Efficient Electrochemical CO2 Reduction
Authors: Li Jing , Chen Wenduo , Lin Rui , Huang Meirong , Wang Min , Chai Maosheng , Zhu Hongwei
Published: September 2021

CO2 reduction reaction (CO2RR) has indispensable significance for carbon recycling and renewable energy production. As typical electrochemical catalysts, Au and Ag show relatively high reaction activity and selectivity in CO2RR. In this study, a series of Ag–Au bimetallic catalysts are designed and synthesized through the thermal evaporation method for efficient yet massive production of electrochemical catalysts. The Ag–Au catalysts show significantly enhanced activity and selectivity in CO2RR, which is mainly attributed to the increased grain boundaries with well‐dispersed single Ag atoms. After the optimization, Au20Ag10 exhibits the best performance with a CO Faraday efficiency of 89% at −0.9 V (vs the reversible hydrogen electrode) with good stability.
Antihypertensive and antihyperlipemic of spirulina (Arthrospira platensis) sauce on patients with hypertension: A randomized triple‐blind placebo‐controlled clinical trial
Authors: Ghaem Far Zohreh , Babajafari Siavash , Kojuri Javad , Mohammadi Salman , Nouri Mehran , Rostamizadeh Pouya , Rahmani Mohammad Hossein , Azadian Mohsen , Ashrafi‐Dehkordi Elham , Zareifard Alireza , Golchin Vafa Reza , Mazloomi Seyed Mohammad
Published: September 2021

Systemic arterial hypertension is an independent risk factor for coronary heart disease, stroke, heart failure, and chronic kidney diseases. Spirulina is microalgae with nutritious ingredients and has potential attenuating effects on chronic diseases including hypertension. Spirulina can be added to food products in order to develop functional foods. The aim of this study was to assess the effects of 8‐week consumption of a salad dressing containing 2 g of spirulina platensis powder versus a placebo dressing on patients with hypertension. In this triple‐blind randomized clinical trial, 48 patients with hypertension were enrolled to receive daily either spirulina‐fortified dressing or placebo for 2 months. A total of 41 patients completed this study. We observed that the consumption of spirulina dressing significantly reduced systolic blood pressure (p = .02), diastolic blood pressure (p = .03), serum triglyceride (p = .01), total cholesterol, and low‐density lipoprotein (LDL) levels, compared to nonsignificant changes in the placebo group. Significant changes in TAC and hs‐CRP levels were observed in none of the groups. According to our findings, spirulina‐fortified dressing as a functional food can be used a supportive treatment for patients with hypertension along with standard antihypertensive drugs. However, further investigations are required for a more comprehensive conclusion.
A novel cumulative EWMA‐sum mean chart
Authors: Haq Abdul
Published: September 2021

Memory‐type charts are well‐recognized as an advanced process monitoring tool because of their sensitive nature against small‐to‐moderate shifts that occur in the process parameters. One of those memory‐type charts is a CUmulative SUM (CUSUM) chart. In order to increase the sensitivity of the CUSUM mean chart, the CUSUM statistic is updated with the CUmulative EWMA‐SUM (CUESUM), which results into the CUESUM chart. The CUESUM chart encompasses the Crosier CUSUM (CCUSUM) chart. Using the Monte Carlo simulations, the run‐length properties of the CUESUM chart are computed. Based on detailed run‐length comparisons, it turns out that the CUESUM chart is more sensitive than the CCUSUM, EWMA, and double EWMA charts when detecting small shifts in the process mean. In addition, the CUESUM chart is uniformly more sensitive than the EWMA‐CUSUM chart. Real and simulated datasets are considered to demonstrate the implementation of the proposed chart.
Effects of low energy availability on female reproductive function
Authors: Iwasa Takeshi , Minato Saki , Imaizumi Junki , Yoshida Atsuko , Kawakita Takako , Yoshida Kanako , Yamamoto Yuri
Published: September 2021

Background

It is known that metabolic and nutritional disturbances induce reproductive dysfunction in females. The main cause of these alterations is reduced gonadotrophin‐releasing hormone (GnRH) secretion from the hypothalamus, and the underlying mechanisms have gradually been elucidated.

Methods

The present review summarizes current knowledge about the effects of nutrition/metabolism on reproductive functions, especially focusing on the GnRH regulation system.

Main findings

Various central and peripheral factors are involved in the regulation of GnRH secretion, and alterations in their activity combine to affect GnRH neurons. Satiety‐related factors, i.e., leptin, insulin, and alpha‐melanocyte‐stimulating hormone, directly and indirectly stimulate GnRH secretion, whereas orexigenic factors, i.e., neuropeptide Y, Agouti‐related protein, orexin, and ghrelin, attenuate GnRH secretion. In addition, kisspeptin, which is a potent positive regulator of GnRH, expression is reduced by metabolic and nutritional disturbances.

Conclusion

These neuroendocrine systems may be defensive mechanisms, which help organisms to survive adverse conditions by temporarily suppressing reproduction.
Performance bounds for VDE‐SAT R‐Mode
Authors: Šafář Jan , Grant Alan , Bransby Martin
Published: September 2021

There has been growing interest within the satellite navigation community in the possibility of delivering positioning and timing services from existing or emerging constellations of Low‐Earth Orbit communication satellites. At the same time, the international maritime community has been investigating the potential use of communication signals transmitted from shore‐based stations for positioning—a concept commonly referred to as ‘ranging mode’, or R‐Mode. The driving force for these developments is the desire to reduce the reliance on traditional Global Navigation Satellite Systems (GNSS). One of the technologies being considered for use in R‐Mode is the evolution of the Automatic Identification System (AIS) known as the Very High Frequency Data Exchange System (VDES). VDES has a terrestrial and a satellite component. The feasibility of using terrestrial VDES transmissions for ranging was studied in a previous publication by the authors. This paper builds on the previous study and extends its results to the satellite component of VDES. Statistical bounds on the ranging error are derived for all downlink waveforms currently being considered for use in satellite VDES and for several custom‐designed transmission formats. The analysis supports the feasibility of using both the existing and custom waveforms in ranging applications and points to related trade‐offs that will need to be considered in the design of satellite VDES R‐Mode systems.
Bayesian inference of dependent kappa for binary ratings
Authors: Sen Ananda , Li Pin , Ye Wen , Franzblau Alfred
Published: September 2021

In medical and social science research, reliability of testing methods measured through inter‐ and intraobserver agreement is critical in disease diagnosis. Often comparison of agreement across multiple testing methods is sought in situations where testing is carried out on the same experimental units rendering the outcomes to be correlated. In this article, we first developed a Bayesian method for comparing dependent agreement measures under a grouped data setting. Simulation studies showed that the proposed methodology outperforms the competing methods in terms of power, while maintaining a decent type I error rate. We further developed a Bayesian joint model for comparing dependent agreement measures adjusting for subject and rater‐level heterogeneity. Simulation studies indicate that our model outperforms a competing method that is used in this context. The developed methodology was implemented on a key measure on a dichotomous rating scale from a study with six raters evaluating three classification methods for chest radiographs for pneumoconiosis developed by the International Labor Office.
A Bayesian approach for event predictions in clinical trials with time‐to‐event outcomes
Authors: Aubel Paul , Antigny Marine , Fougeray Ronan , Dubois Frédéric , Saint‐Hilary Gaëlle
Published: September 2021

In clinical trials with time‐to‐event outcome as the primary endpoint, the end of study date is often based on the number of observed events, which drives the statistical power and the sample size calculation. It is of great value for study sponsors to have a good understanding of the recruitment process and the event milestones to manage the logistical tasks, which require a considerable amount of resources. The objective of the proposed statistical approach is to predict, as accurately as possible, the timing of an analysis planned once a target number of events is collected. The method takes into account the enrollment, the time to event, and the time to censor processes, using Weibull models in a Bayesian framework. We also consider a possible delay in the event reporting by the investigators, and covariates may also be included. Several metrics can be obtained, such as the probability of study completion at specific timepoints or the credible interval of the date of study completion. The approach was applied to oncology trials, with progression‐free survival as primary outcome. A retrospective analysis shows the accuracy of the approach on these examples, as well as the benefit of updating the predictive probability of study completion as data are accumulating or new information becomes available. We also evaluated the performances of the proposed method in a comprehensive simulation study.
Interaction screening for high‐dimensional heterogeneous data via robust hybrid metrics
Authors: Xiong Wei , Pan Han
Published: September 2021

A novel model‐free interaction screening approach called the hybrid metrics is introduced for high‐dimensional heterogeneous data analysis. The metrics established based on the variation of conditional joint distribution function are measurements of interaction that include both size and direction. They are robust and can work with many types of response variables, including continuous, discrete, and categorical variables. We can apply the hybrid metrics to effective interaction selection for classification, response index models, and Poisson regression, among others. When dealing with classification, the hybrid metrics are capable of capturing both nonlinear category‐general and category‐specific interaction effects, providing us with a comprehensive overview and precise discovery of category information. When faced with a continuous response, the hybrid metrics perform fairly well even if the signal strength is weak, behaving as if the true interactions were known. To facilitate implementation, a fast two‐stage procedure which naturally and efficiently enforces both strong and weak heredity is advocated. We further demonstrate their superior performances over popular competitors by exhaustive simulations and a SRBCT real data example. Supplementary materials for this article are available online.
A comprehensive survey on nature‐inspired algorithms and their applications in edge computing: Challenges and future directions
Authors: Adhikari Mainak , Srirama Satish Narayana , Amgoth Tarachand
Published: September 2021

Driven by the vision of real‐time applications and smart communication, recent years have witnessed a paradigm shift from centralized cloud computing toward distributed edge computing. The main features of edge computing are to drag the cloud services toward the network edge with dramatic reductions of latency while increasing the resource utilization of the network and computing devices. Being the natural extension of cloud computing, edge computing inherits a variety of research challenges and brings forth different new issues to solve. These challenges are dealing with solving complex optimization problems including scheduling and processing real‐time applications. Nature‐inspired meta‐heuristic (NIMH) algorithm is an overarching term in the field of an optimization problem that provides robust solutions to the NP‐complete problems, from computationally tractable approximate solutions to real‐time optimization strategies. Nowadays, different NIMH algorithms have been applied in the field of edge computing for solving various research challenges including resource placement and scheduling, communication, mobility, and edge controlling with higher efficiency. In this survey, we classify the existing NIMH into three categories based on their nature of works and included fuzzy logic and systems in the field of edge networks along with different research challenges. Further, we introduce different challenges and future directions to identify promising research works in edge computing.
Variable, full‐scale tester for tunnel linings
Authors: Petraroia Diego N. , Mark Peter
Published: September 2021

This contribution presents a new tester for tunnel lining segments in the final serviceability load stage. It aims to concentrate the resources of testing laboratories on a single segment capturing most of the real conditions present in real tunnels. Its variability is presented, that is, the geometrical and mechanical configurations it can adapt to. Its performance is validated by means of a prototype test on a conventionally reinforced tunnel lining segment. Horizontal and vertical loads are applied simultaneously to simulate similar loading conditions as in real tunnels. To this end, three hydraulic cylinders are coupled, so that forces up to 5 MN in both directions can be applied. The external loads are introduced radially in a semi‐distributed manner at eight different points of the segment extrados. The kinematics recorded show a proper load distribution on the specimen. Moreover, it brings into light its weak spot, that is, the longitudinal joint.
Structural and economical performance of reinforced concrete frames with Dual‐Phase and TempCore® steel rebars in uncorroded and corroded conditions
Authors: Caprili Silvia , Mattei Francesca , Salvatore Walter
Published: September 2021

In the last decades, the need to develop new enhanced typologies of steel reinforcement bars with improved ductility and durability performance in presence of aggressive environmental conditions progressively increased due to the negative consequences that corrosion showed on the structural capacity of reinforced concrete (RC) buildings. Within the recently concluded NEWREBAR research project, a new reinforcing steel grade with Dual‐Phase (DP) microstructure and selected low‐carbon content chemical composition (kept in the range of the actual European production) was developed, produced, and tested even in presence of accelerated induced corrosion. To understand the impact of the adoption of DP rebars in RC structures, case study buildings were designed, modeled, and analyzed using the new grade and compared to traditional buildings using TempCore® rebars. In the present work, the results of a techno‐economic analysis performed on both DP and TempCore® RC buildings through the evaluation of the expected annual loss (EAL) index is presented for a residential five‐storeys case‐study building, assessing the benefit introduced by adopting the proposed new reinforcing grade even in presence of corrosion.