bluuebunny/crossref_metadata_2025 huggingface dataset:
Lending ears to unheard voices: An empirical analysis of user‐generated content on social media
Authors: Gour Alekh , Aggarwal Shikha , Kumar Subodha
Published: April 2022

Governments and healthcare organizations increasingly pay attention to social media for handling a disease outbreak. The institutions and organizations need information support to gain insights into the situation and act accordingly. Currently, they primarily rely on ground‐level data, collecting which is a long and cumbersome process. Social media data present immense opportunities to use ground data quickly and effectively. Governments and HOs can use these data in launching rapid and speedy remedial actions. Social media data contain rich content in the form of people's reactions, calls‐for‐help, and feedback. However, in healthcare operations, the research on social media for providing information support is limited. Our study attempts to fill the gap mentioned above by investigating the relationship between the activity on social media and the quantum of the outbreak and further using content analytics to construct a model for segregating tweets. We use the case example of the COVID‐19 outbreak. The pandemic has advantages in contributing to the generalizability of results and facilitating the model's validation through data from multiple waves. The findings show that social media activity reflects the outbreak situation on the ground. In particular, we find that negative tweets posted by people during a crisis outbreak concur with the quantum of a disease outbreak. Further, we find a positive association between this relationship and increased information sharing through retweets. Building further on this insight, we propose a model using advanced analytical methods to reduce a large amount of unstructured data into four key categories—irrelevant posts, emotional outbursts, distress alarm, and relief measures. The supply‐side stakeholders (such as policy makers and humanitarian organizations) could use this information on time and optimize resources and relief packages in the right direction proactively.
Physcomitrium (Physcomitrella) patens endo‐glucanase 16 is involved in the cell wall development of young tissue
Authors: Behar Hila , Samuels Anne Lacey , Brumer Harry
Published: April 2022

Plants maintain large repertoires of carbohydrate‐active enzymes (CAZymes)—comprising between 3% and 10% of their genomes—to synthesize, modify, and degrade the polysaccharide components of the cell wall. We recently identified a unique group of plant endo‐glucanases from Glycoside Hydrolase Family 16, viz. EG16 orthologs, which constitute a sister clade to the well‐known XYLOGLUCAN ENDO‐TRANSGLYCOSYLASE/HYDROLASE (XTH) gene products. Biochemical analysis of EG16 orthologs from poplar (Populus trichocarpa), grapevine (Vitis vinifera), and spreading earthmoss (Physcomitrium patens) has demonstrated that these endo‐glucanases are distinctly active on cell wall matrix glycans, mixed‐linkage β(1,3);β(1,4)‐glucan and xyloglucan (XyG), and that enzyme structure and specificity is highly conserved across diverse plant lineages. However, the physiological role of EG16 orthologs in any species is presently unknown. To shed light on EG16 function in vivo, here we performed reverse genetics and protein localization analyses of the single EG16 ortholog in the model moss P. patens, where this gene is highly expressed in young, expanding tissues, particularly in protonema. Surprisingly, deletion of the PpEG16 gene by homologous recombination led to an increase in growth, as well as accelerated senescence. Notably, the PpEG16 protein was shown to co‐localize with XyG in the cell wall of protonema tissue, specifically at cell tips, despite lacking a secretion signal peptide. Although the precise biological role of EG16 orthologs remains elusive, our results implicate these highly conserved glycoside hydrolases in cell wall polysaccharide remodeling and recycling. We anticipate that these foundational results will inform future studies on EG16 function across plant lineages.
Delving deeper into the link between sugar transport, sugar signaling, and vascular system development
Authors: Dinant Sylvie , Le Hir Rozenn
Published: April 2022

Plant growth and development rely on the transport and use of sugars produced during photosynthesis. Sugars have a dual function as nutrients and signal molecules in the cell. Many factors maintaining sugar homeostasis and signaling are now identified, but our understanding of the mechanisms involved in coordinating intracellular and intercellular sugar translocation is still limited. We also know little about the interplay between sugar transport and signaling and the formation of the vascular system, which controls long‐distance sugar translocation. Sugar signaling has been proposed to play a role; however, evidence to support this hypothesis is still limited. Here, we exploited recent transcriptomics datasets produced in aerial organs of Arabidopsis to identify genes coding for sugar transporters or signaling components expressed in the vascular cells. We identified genes belonging to sugar transport and signaling for which no information is available regarding a role in vasculature development. In addition, the transcriptomics datasets obtained from sugar‐treated Arabidopsis seedlings were used to assess the sugar‐responsiveness of known genes involved in vascular differentiation. Interestingly, several key regulators of vascular development were found to be regulated by either sucrose or glucose. EspeciallyCLE41, which controls the procambial cell fate, was oppositely regulated by sucrose or glucose in these datasets. Even if more experimental data are necessary to confirm these findings, this survey supports a link between sugar transport/signaling and vascular system development.
Loneliness and Depression among Community Older Adults during the COVID‐19 Pandemic: A cross‐sectional study
Authors: Alhalaseh Lana , Kasasbeh Farah , Al‐Bayati Mariam , Haikal Lubna , Obeidat Kinan , Abuleil Abdallah , Wilkinson Iain
Published: April 2022

Background

Social isolation has been recommended for reducing older adults' mortality and severe cases of COVID illness. That has resulted in unavoidable consequences of mental ill‐health. This study aimed to examine the impact of the COVID‐19 lockdown on the development of loneliness and depression and to analyse the factors associated with these conditions among community‐dwelling older adults in Jordan.

Methods

A cross‐sectional survey was conducted with a random sample of 456 community older adults contacted by telephone three weeks after the first pandemic lockdown in April 2020. The study instrument included the screening three‐item UCLA Loneliness Scale, the Geriatric Depression Scale, and relevant medical and functional history.

Results

The mean age was 72.48 ± 6.84 years, and 50.2% were women. 41.4% were lonely, and of those 62% had a positive screen for depression. The mean UCLA score was significantly higher during the lockdown than before. Loneliness was significantly associated with being unmarried, having never worked previously, and being functionally dependent. Lonely participants were 1.65 times more likely to have depression. Likewise, a previous history of depression and cognitive impairment, multimorbidity, poor self‐perceived health, and concern about contracting COVID infection were significant predictors of depression.

Conclusion

The COVID‐19 pandemic has had a heavy toll on older adults' mental health, particularly those with multimorbidity, baseline functional dependence, and those with a previous history of depression and cognitive impairment. Targeting these high‐risk groups is important in order to minimize loneliness, depression, and subsequent increased morbidity. Using all‐inclusive language might minimize ageism and the fear of catching an infection.
Decolonizing Theological Education: Learning from Latinx, Womanist, and Asian Voices for Transformative PedagogyAtando Cabos: Latinx Contributions to Theological Education, ElizabethConde‐Frazier, Eerdmans, 2021 (ISBN 978‐0‐8028‐7901‐1), vii + 151 pp., pb $19.99Notes of a Native Daughter: Testifying in Theological Education, KeriDay, Eerdmans, 2021 (ISBN 978‐0‐8028‐7882‐3), viii + 144 pp., pb $19.99Attempt Great Things for God: Theological Education in Diaspora, Chloe T.Sun, Eerdmans, 2020 (ISBN 978‐0‐8028‐7842‐7), vi + 142 pp., pb $19.99
Authors: Dominiak Paul
Published: April 2022

Theological education—and society more broadly—stands critically ‘between the times’. Contemporary theological education exists between traditional modes of formation implicitly shaped by western colonialism and an uncertain future occasioned by seismic shifts around funding, admissions, ecologies of formation, and globalization. This ‘between the times’ moment both threatens the survival of theological education institutes and also unveils the historic and ongoing complicity of theological education in the wider racist colonial legacies of white privilege and hegemony. The same ‘in between’ moment also proffers to theological education the possibility to embrace diverse voices and transformative pedagogies within theological education as part of decolonization and decolonizing the curriculum. Embracing decolonizing theology will both save the soul of theological education and may help it survive through embracing collaborative, creative, and intersectional models of education that meet pragmatic needs as well as moral imperatives. This article explores three publications by Elizabeth Conde‐Frazier, Keri Day, and Chloe Sun that offer Latinx, womanist, and Asian theological perspectives on decolonizing theology in this ‘between the times’ moment of theological education. Setting out first the ecclesial and then the wider political contexts of these three works, the article examines how they imagine new decolonized possibilities for theological education. Following Graham Ward, the article develops how all three authors in their own ways argue that decolonizing theology and theological education entails ‘provincializing’ the (white) western context as normative, ‘translating’ or ‘transplanting’ theology back into culturally authentic discourses that contend meaning and deconstruct white power, and positively ‘affirming’ the varied cultural identities in which theological meaning is located.
Posterior Summaries of Grocery Retail Topic Models: Evaluation, Interpretability and Credibility
Authors: Vega Carrasco Mariflor , Manolopoulou Ioanna , O'Sullivan Jason , Prior Rosie , Musolesi Mirco
Published: April 2022

Understanding the shopping motivations behind market baskets has significant commercial value for the grocery retail industry. The analysis of shopping transactions demands techniques that can cope with the volume and dimensionality of grocery transactional data while delivering interpretable outcomes. Latent Dirichlet allocation (LDA) allows processing grocery transactions and the discovering of customer behaviours. Interpretations of topic models typically exploit individual samples overlooking the uncertainty of single topics. Moreover, training LDA multiple times show topics with large uncertainty, that is, topics (dis)appear in some but not all posterior samples, concurring with various authors in the field. In response, we introduce a clustering methodology that post-processes posterior LDA draws to summarise topic distributions represented as recurrent topics. Our approach identifies clusters of topics that belong to different samples and provides associated measures of uncertainty for each group. Our proposed methodology allows the identification of an unconstrained number of customer behaviours presented as recurrent topics. We also establish a more holistic framework for model evaluation, which assesses topic models based not only on their predictive likelihood but also on quality aspects such as coherence and distinctiveness of single topics and credibility of a set of topics. Using the outcomes of a tailored survey, we set thresholds that aid in interpreting quality aspects in grocery retail data. We demonstrate that selecting recurrent topics not only improves predictive likelihood but also outperforms interpretability and credibility. We illustrate our methods with an example from a large British supermarket chain.
Sources of support and Conflicts of interests
Authors: Srivastav Sukeshana , Goel Shubhi , Tewari Nitesh
Published: April 2022

The aim of this letter to the editor was to highlight the importance of adding sources of support and conflicts of interests in the published articles so that they are adequately analysed for their quality by using AMSTAR‐2 tool.
Virtual Reality as parent education tool in pre‐surgical management of cleft lip and palate affected infants—A pilot study
Authors: Deshmukh Seema , Murthy Prashanth Sadashiva , Singh Birti , Contractor Inshiya
Published: April 2022

Aim

To assess the influence of virtual reality (VR) in parent acceptance of the pre‐surgical nasoalveolar molding (PNAM) as a pre surgical care to the cleft lip and palate affected infants.

Material and Methods

Descriptive Cross sectional pilot study design was planned to assess the pre surgical management of the cleft lip and palate. Twenty parents/caregivers of the infants were randomly divided into two groups. Twelve participants received education through conventional education module (Group I) using verbal explanation supported by the photographs. Another 12 participants received education through customized VR based educational video (Group II). After the education, the parents were provided with questionnaire to assess the acceptance of the treatment procedure. The survey response rate was represented in percentage.

Results

The results of the study indicated that most of the parents were aware of the feeding plate or obturators as an aid in assisting feeding practices among cleft lip and palate affected infants. However, only 33% of participants in Group I were able to understand the doctor's explanation regarding the PNAM whereas 100% of participants in Group II were able to visualize the benefits of PNAM. These participants were willingly accepting PNAM as essential pre‐surgical care.

Conclusion

Innovative approaches are essential in patient education modalities as the success of any treatment outcome largely depends on the patient acceptance. Within the limits of this study, VR has been successful in the educating the parents and caregivers regarding the acceptance of PNAM therapy in cleft affected infants.
Illustrated booklet of Brazilian sign language for dentistry
Authors: Santos Rafaela Santos dos , Corrêa Vania Castro , Santos Rita Correa dos , Pereira Fabricio Moraes , Corrêa Davi Lavareda , Pinto Cássio Gonçalves , Pedreira Erick Nelo , Pedreira Juliana de Borborema Garcia
Published: April 2022

Aims

This manuscript aimed to produce an illustrated booklet of Brazilian sign language (LIBRAS) booklet to facilitate the communication between dentists (and academics) and deaf patients during dental treatment and other healthcare promotion activities.

Methods and Results

A literature review was conducted to select signs, symptoms, and diseases related to dentistry expressed in LIBRAS; in addition, photographs were taken to illustrate and produce the booklet. The booklet (in PDF format) was made available on an open‐access website and printed copies were freely distributed at the dental clinics of the Federal University of Pará.

Conclusion

Learning of specific LIBRAS is extremely important to guarantee social inclusion and improve dental treatment of deaf patients.
Development of the European Portuguese version of the oral health assessment tool: Content validity and reliability study in an elderly population
Authors: Cerveira Filipa Ramos , Matos Maria Assunção Coelho , Sa‐Couto Pedro
Published: April 2022

Aims

Poor oral health is a risk factor for aspiration pneumonia (AP), especially in elderly patients at risk of oropharyngeal dysphagia (OD). In Portugal, available tools to screen oral problems in nursing homes are scarce. The oral health assessment tool (OHAT) is a screening tool that assesses elderly residents’ oral health. This study aims to translate and validate the tool for the European Portuguese (EP) context.

Methods

The original version was translated into EP throughout a forward‐backward translation process. An instruction manual was created. Content of both documents were assessed by a panel of eight experts. The content validity Index was calculated. A reliability study was conducted in three nursing homes by two speech and language therapists in two different moments, separated by 48 h.

Results

A sample of 30 institutionalized elderly with a mean age of 77 years was analyzed. The EP version and its instruction manual presented a content validity Index greater than 0.88 in all its items. Total scores showed excellent inter‐rater and good intra‐rater results.

Conclusion

The EP version showed to be a reliable and valid tool for the screening of oral health conditions of institutionalized older adults at risk of OD.
Reorganizations of Gendered Labor During the COVID‐19 Pandemic: A Review and Suggestions for Further Research
Authors: Leap Braden , Stalp Marybeth C. , Kelly Kimberly
Published: April 2022

Across a range of countries, analysts have found that adaptations to the COVID‐19 pandemic often exacerbated previously existing labor inequalities between men and women in formal employment markets and households. This has been especially true for mothers with children in their households. Drawing on decades of sociological and feminist scholarship on labor, we suggest the following three strategies to strengthen ongoing research concerning pandemic‐induced reorganizations of gendered labor. First, ongoing research should expand considerations of gendered labor to account for more types of work and workers. Second, initial findings should be extended through the continued utilization of diverse methodologies to better account for the ambivalent experiences and meanings associated with emergent reorganizations of gendered work during the pandemic. Finally, ongoing research should pursue intersectional analyses of gendered labor that are sensitive to the complex dynamics of place and time. By expanding and strengthening considerations of gendered labor in these manners, ongoing analyses could generate more comprehensive, precise findings that better guide policy interventions meant to address the gendered inequities being sharpened by the pandemic. Foundational theoretical understandings of gendered labor and its associated inequalities could also be extended.
Can end‐user feedback inform ‘Responsibilisation’ of India's policy landscape for agri‐digital transition?*
Authors: Kumar Anupam , Basu Soutrik
Published: April 2022

Agrarian transformations are imagined globally through digital agriculture. Most ambitious agrarian plans in India also identify the application of digital technologies to drive the next agro‐food revolution. However, the concerns around the ‘soft impacts’ of the agri‐digital transition, including socioethical concerns and farmers’ perceptions, have received relatively little attention among innovators and policymakers. Thus, through a combination of qualitative content analysis and topic modelling, this article studies end‐user feedback on smart farming apps in India. Emerging themes from the feedback analysis inform an understanding of the attributes of responsibilisation in policies through which agri‐digitalisation is being planned and introduced. The main findings indicate that agri‐digital innovations need to be inclusive of nonhegemonic vernaculars, responsive to farmers’ data privacy and ownership considerations and focus on producing simple, actionable insights for farmers instead of bombarding them with conflicting ideas. At the policy level, this article argues that the Indian policy landscape needs to be reformed substantially. This further suggests that India may need a new institutional architecture to manage the digital transition in agriculture.
Clinical Teaching Fellows, the new norm?—Experiences of fellows and education faculty
Authors: Couchman Dan , Donnachie Douglas , Tarr Jo , Bull Stephanie
Published: April 2022

Background

In the United Kingdom, there is an increasing tendency for doctors in the first 2 years after graduation, to step off the training pathway and take up Clinical Teaching Fellow (CTF) positions. We aimed to explore stakeholder experiences of CTF positions to inform future planning and support.

Methods

Individual semi‐structured interviews with 10 stakeholders (five CTFs and five education faculty members) from one institution in England were conducted. Interviews explored the participants' views of the CTF position, its benefits and challenges. Inductive thematic analysis was performed.

Results

CTFs and education faculty views strongly aligned and three themes were identified. These were (1) developing a career, (2) developing confidence and competence as a clinical teacher and (3) developing a position that works for all. Participants reported that the CTF position allowed time for specialty decision making and curriculum‐vitae strengthening and provide CTFs with the opportunity to work autonomously and to establish a better work–life balance by stepping away from training pressures and focusing on other aspects of life. There were differing thoughts on how the position should be structured, although retaining a clinical role with boundaries to constrain competing responsibilities was important.

Conclusion

A brief hiatus in clinical training, where individuals feel supported to progress personally and professionally and to renew their energy for the next steps of clinical training, seems important. The ideologies of providing the CTFs with autonomy, time to explore options, recharge and form connections with colleagues should be considered when structuring the posts.
Feasibility study of student telehealth interviews
Authors: Zaccariah Zara R. , Irvine Alison W. , Lefroy Janet E.
Published: April 2022

Background

The COVID‐19 pandemic has led to medical students being taught remote clinical communication modalities (telephone and video). Junior students have not generally been included in this and have had less patient contact than previously. This study aimed to examine the feasibility from the junior student viewpoint of conducting both modalities of patient telehealth interviews.

Methods

An electronic questionnaire was used to discover Year 1 student reasons for their preferred modality after they had conducted one telephone and one video interview in pairs with a patient volunteer. Student views on the challenge and benefits of each were also sought.

Findings

A total of 55 (32.7% of the cohort) responded, of whom 82% preferred video consultation, 75.6% of those stating being able to see their patient/partner was a key factor. About 5% preferred telephone interview, and 13% had no preference. Telephone interviews were perceived as the more challenging (40% versus 12.7%); however, challenge did not directly link with lack of comfort. There were some technical/connectivity issues with both modalities, and the telephone call system was more complex to set up. Turn‐taking was more difficult by telephone without visual cues.

Discussion

This is the first direct comparison study in junior medical students of real patient interviews by video or telephone. Students embraced the challenge and, although preferring video and finding telephone more challenging, valued each as an educational experience.

Conclusions

Telehealth interviews with patients for junior students are feasible, give needed patient exposure, practical insights into remote modalities and consolidate communication skills learnt in the classroom.
Cities in Castells' Theorising of Social Space
Authors: Taylor Peter J. , Derudder Ben
Published: April 2022

Manuel Castells has been a leading figure in urban studies since the 1970s and is widely acclaimed for combining Marxist theoretical thinking with practical policy proposals. As a social theorist, his particular focus on the spatiality of cities has led to him becoming very influential in urban geography as specifically evidenced by his two invited papers in TESG in 1993 and 2002. In this paper, we develop an ontological critique of Castells' employing the mainstream position that cities reflect the nature of the societies that encompasses them, whereas we consider cities as the makers of their encompassing society. The TESG papers are broadly reviewed by contrasting their governance/policy approach with Jane Jacobs' economics/development approach. This critique does not diminish our appreciation for Castells' contribution to urban studies, rather the ontological critique is used as a tool for providing clarity of scholarship, not another episode of academic squabbling in urban studies.
A framework for social media information flow analytics in cyberspace and physical space
Authors: Li Manqi , He Xiaoyu , Sun Zhuo , Wen Yongning
Published: April 2022

Communication in online social media naturally forms information flow from senders to receivers. With the proliferation of location‐aware social media services such as Twitter, information flow shaped on these platforms is becoming more deeply and extensively embedded in the physical world. Therefore, growing interest has been raised in discovering the spatiotemporal patterns of information flow in location‐aware social media, aiming for a holistic understanding of the social dynamics in the nested cyber and physical world. This article addresses this interest by proposing a framework for information flow analytics based on a spatiotemporal clustering method designed for large data streams with location information. The framework was implemented as an open‐source tool, and its performance was examined by two case studies using Twitter data streams. It is suggested that this framework has well addressed the new requirements and challenges arising from social media data streams, effectively visualized information flow on maps, and demonstrated its feasibility of supporting downstream spatiotemporal analysis and applications.
Comparison of cryoprotectants in hematopoietic cell infusion–related adverse events
Authors: Ikeda Kazuhiko , Minakawa Keiji , Yamahara Kenichi , Yamada‐Fujiwara Minami , Okuyama Yoshiki , Fujiwara Shin‐ichiro , Yamazaki Rie , Kanamori Heiwa , Iseki Tohru , Nagamura‐Inoue Tokiko , Kameda Kazuaki , Nagai Kazuhiro , Fujii Nobuharu , Ashida Takashi , Hirose Asao , Takahashi Tsutomu , Ohto Hitoshi , Ueda Koki , Tanosaki Ryuji
Published: April 2022

Background

The standard cryoprotectant for human cellular products is dimethyl sulfoxide (DMSO), which is associated with hematopoietic cell infusion‐related adverse events (HCI‐AEs) in hematopoietic stem cell transplantation including peripheral blood stem cell (PBSC) transplantation (PBSCT). DMSO is often used with hydroxyethyl starch (HES), which reduces DMSO concentration while maintaining the postthaw cell recovery. The cryoprotectant medium CP‐1 (Kyokuto Pharmaceutical Industrial) is widely used in Japan. After mixture of a product with CP‐1, DMSO and HES concentrations are 5% and 6%, respectively. However, the safety profile of CP‐1 in association with HCI‐AEs has not been investigated.

Study Design and Methods

To compare CP‐1 with other cryoprotectants, we conducted a subgroup analysis of PBSCT recipients in a prospective surveillance study for HCI‐AEs. Moreover, we validated the toxicity of CP‐1 in 90 rats following various dose administration.

Results

The PBSC products cryopreserved with CP‐1 (CP‐1 group) and those with other cryoprotectants, mainly 10% DMSO (non‐CP‐1 group), were infused into 418 and 58 recipients, respectively. The rate of ≥grade 2 HCI‐AEs was higher in the CP‐1 group, but that of overall or ≥grade 3 HCI‐AEs was not significantly different, compared to the non‐CP‐1 group. Similarly, after propensity score matching, ≥grade 2 HCI‐AEs were more frequent in the CP‐1 group, but the ≥grade 3 HCI‐AE rate did not differ significantly between the groups. No significant toxicity was detected regardless of the CP‐1 dose in the 90 rats.

Conclusions

Infusion of a CP‐1‐containing PBSC product is feasible with the respect of HCI‐AEs.
Optimized Phonon Band Discretization Scheme for Efficiently Solving the Nongray Boltzmann Transport Equation
Authors: Hu Yue , Shen Yongxing , Bao Hua
Published: April 2022

The phonon Boltzmann transport equation (BTE) is an important tool for studying the nanoscale thermal transport. Because phonons have a large spread in their properties, the nongray (i.e., considering different phonon bands) phonon BTE is needed to accurately capture the nanoscale transport phenomena. However, BTE solvers generally require large computational cost. Nongray modeling imposes significant additional complexity on the numerical simulations, which hinders the large-scale modeling of real nanoscale systems. In this work, we address this issue by a systematic investigation on the phonon band discretization scheme using real material properties of four representative materials, including silicon, gallium arsenide, diamond, and lead telluride. We find that the schemes used in previous studies require at least a few tens of bands to ensure the accuracy, which requires large computational costs. We then propose an improved band discretization scheme, in which we divide the mean free path domain into two subdomains, one on either side of the inflection point of the mean free path accumulated thermal conductivity, and adopt the Gauss–Legendre quadrature for each subdomain. With this scheme, the solution of the phonon BTE converges (error < 1%) with less than ten phonon bands for all these materials. The proposed scheme allows significantly reducing the time and memory consumption of the numerical BTE solver, which is an important step toward large-scale phonon BTE simulations for real materials.
Reducing Full-Field Residual Stress of Girth Weld With Thick Wall by Combining Local PWHT and Water Jet Peening
Authors: Luo Yun , Zhang Qian , Zheng Hong-Xiang , Jiang Wenchun
Published: April 2022

In this paper, a new controlling method combined local postweld heat treatment (PWHT) and water jet peening (WJP) was proposed to reduce full-field residual stress of girth weld with thick wall. The finite element analysis with sequential coupling method and experiment measurement were performed to study the residual stresses distribution before and after the new controlling method. The results show that the hoop and axial stresses through the thickness are all decreased greatly by using the new controlling method. As long as the new controlling method is used with appropriate parameters, the residual stresses on inner surface can be reduced from tensile stresses to compressive stresses, which greatly improve the resistance ability to stress corrosion of inner surface.
Positional Accuracy Improvement of an Industrial Robot Using Feedforward Compensation and Feedback Control
Authors: Li Bo , Zhang Wei , Li Yufei , Tian Wei , Wang Changrui
Published: April 2022

Industrial robots play an important role in the transformation and upgrading of aviation manufacturing technology by their advantages of high flexibility, high efficiency, and low costs compared to the conventional computerised numerical control machine. However, due to the serial structure design of the main body, the industrial robot has low absolute positional accuracy, which limits its popularization and application in the field of high-precision manufacturing. The purpose of this paper is to develop a robot accuracy improvement method using feedforward compensation and joint closed-loop feedback correction considering the influence of joint backlash. The experimental results show that the positional error of the compensated robot by the proposed method is reduced from 0.76 mm to 0.18 mm under no-load conditions, and the hole's positional accuracy is to 0.25 mm in the robotic drilling experiment.
Electric-Field-Assisted Contact Mode AFM-Based Nanolithography with Low Stiffness Conductive Probes
Authors: Zhou Huimin , Jiang Yingchun , Dmuchowski Christopher M , Ke Changhong , Deng Jia
Published: April 2022

Electric-field-assisted atomic force microscope (E-AFM) nanolithography is a novel polymer-patterning technique that has diverse applications. E-AFM uses a biased AFM tip with conductive coatings to make patterns with little probe-sample interaction, which thereby avoids the tip wear that is a major issue for contact-mode AFM-based lithography, which usually requires a high probe-sample contact force to fabricate nanopatterns; however, the relatively large tip radius and large tip-sample separation limit its capacity to fabricate high-resolution nanopatterns. In this paper, we developed a contact mode E-AFM nanolithography approach to achieve high-resolution nanolithography of poly (methyl methacrylate) (PMMA) using a conductive AFM probe with a low stiffness (~0.16 N/m). The nanolithography process generates features by biasing the AFM probe across a thin polymer film on a metal substrate. A small constant force (0.5-1 nN) applied on the AFM tip helps engage the tip-film contact, which enhances nanomachining resolution. This E-AFM nanolithography approach enables high-resolution nanopatterning with feature width down to ~16 nm, which is less than one half of the nominal tip radius of the employed conductive AFM probes.
An Investigation of Integrated Multiscale Three-Dimensional Printing for Hierarchical Structures Fabrication
Authors: Li Xiangjia , Baldacchini Tommaso , Chen Yong
Published: April 2022

Nature provides us with a large number of functional material systems consisting of hierarchical structures, where significant variations in dimensions are present. Such hierarchical structures are difficult to build by traditional manufacturing processes due to manufacturing limitations. Nowadays, three-dimensional (3D) objects with complex structures can be built by gradually accumulating in a layer-based additive manufacturing (AM); however, the hierarchical structure measured from macroscale to nanoscale sizes still raises significant challenges to the AM processes, whose manufacturing capability is intrinsically specified within a certain scope. It is desired to develop a multiscale AM process to narrow this gap between scales of feature in hierarchical structures. This research aims to investigate an integration approach to fabricating hierarchical objects that have macro-, micro-, and nano-scales features in an object. Firstly, the process setup and the integrated process of two-photon polymerization (TPP), immersed surface accumulation (ISA), and mask image projection-based stereolithography (MIP-SL) were introduced to address the multiscale fabrication challenge. Then, special hierarchical design and process planning toward integrating multiple printing processes are demonstrated. Lastly, we present two test cases built by our hierarchical printing method to validate the feasibility and efficiency of the proposed multiscale hierarchical printing approach. The results demonstrated the capability of the developed multiscale 3D printing process and showed its future potential in various novel applications, such as optics, microfluidics, cell culture, as well as interface technology.
End-of-Life Corrosion Estimation and Profile of Ship Hull Structure: Nonparametric Statistical Analysis of Medium Endurance Cutters
Authors: Ayyub Bilal M. , Stambaugh Karl A. , McGill William L.
Published: April 2022

Corrosion in hull structure of Coast Guard cutters is a primary degradation mode that accounts for a significant portion of depot budgets and the occasional unavailability of ships in general. Corrosion exhibits great variability spatially and temporally. This paper presents, summarizes, and analyzes a one-of-a-kind dataset for end-of-life corrosion estimation and profile of ship hull structure. The dataset was created over several years and on several vessels, and collected by maintenance personnel at several geographic locations. This study analyzes wastage data due to corrosion that were systematically collected in 2007–2008 from twelve 210-foot medium endurance cutters, commissioned in 1964–1969, in the form of thickness measurement using visual inspection and ultrasonic testing methods. A total of 76,091 thickness measurements were analyzed at positions covering the entire hulls. The measured corrosion levels mean is about 0.02–0.04 in. (1 in. = 25.4 mm), i.e., 6–14% of the as-built thicknesses after no more than 43 years of use of these 12 cutters as of 2007; however, the analysis of outliers indicates that the average wastage values can be misleading in predicting extreme corrosion. A method is proposed for estimating the counts and intensity of outliers. Examining geographic locations of the operations of these cutters and corrosion revealed that southern warm water led to appreciably larger corrosion compared to the northern colder waters, at a ratio of about 1.25–1.5.
Examining Penetration Tester Behavior in the Collegiate Penetration Testing Competition
Authors: Meyers Benjamin S. , Almassari Sultan Fahad , Keller Brandon N. , Meneely Andrew
Published: April 2022

Penetration testing is a key practice toward engineering secure software. Malicious actors have many tactics at their disposal, and software engineers need to know what tactics attackers will prioritize in the first few hours of an attack. Projects like MITRE ATT&CK™ provide knowledge, but how do people actually deploy this knowledge in real situations? A penetration testing competition provides a realistic, controlled environment with which to measure and compare the efficacy of attackers. In this work,
we examine the details of vulnerability discovery and attacker behavior with the goal of improving existing vulnerability assessment processes
using data from the 2019 Collegiate Penetration Testing Competition (CPTC). We constructed 98 timelines of vulnerability discovery and exploits for 37 unique vulnerabilities discovered by 10 teams of penetration testers. We grouped related vulnerabilities together by mapping to Common Weakness Enumerations and MITRE ATT&CK™. We found that (1) vulnerabilities related to improper resource control (e.g., session fixation) are discovered faster and more often, as well as exploited faster, than vulnerabilities related to improper access control (e.g., weak password requirements), (2) there is a clear process followed by penetration testers of discovery/collection to lateral movement/pre-attack. Our methodology facilitates quicker analysis of vulnerabilities in future CPTC events.
Information Leakage Games: Exploring Information as a Utility Function
Authors: Alvim Mário S. , Chatzikokolakis Konstantinos , Kawamoto Yusuke , Palamidessi Catuscia
Published: April 2022

A common goal in the areas of secure information flow and privacy is to build effective defenses against unwanted leakage of information. To this end, one must be able to reason about potential attacks and their interplay with possible defenses. In this article, we propose a game-theoretic framework to formalize strategies of attacker and defender in the context of information leakage, and provide a basis for developing optimal defense methods. A novelty of our games is that their utility is given by information leakage, which in some cases may behave in a non-linear way. This causes a significant deviation from classic game theory, in which utility functions are linear with respect to players’ strategies. Hence, a key contribution of this work is the establishment of the foundations of information leakage games. We consider two kinds of games, depending on the notion of leakage considered. The first kind, the

QIF
-games

, is tailored for the theory of quantitative information flow. The second one, the

DP
-games

, corresponds to differential privacy.
Simulating Brittle Fracture with Material Points
Authors: Fan Linxu , Chitalu Floyd M. , Komura Taku
Published: April 2022

Large-scale topological changes play a key role in capturing the fine debris of fracturing virtual brittle material. Real-world, tough brittle fractures have dynamic branching behaviour but numerical simulation of this phenomena is notoriously challenging. In order to robustly capture these visual characteristics, we simulate brittle fracture by combining elastodynamic continuum mechanical models with rigid-body methods: A continuum damage mechanics (CDM) problem is solved, following rigid-body impact, to simulate crack propagation by tracking a damage field. We combine the result of this elastostatic continuum model with a novel technique to approximate cracks as a non-manifold mid-surface, which enables accurate and robust modelling of material fragment volumes to compliment fast-and-rigid shatter effects. For enhanced realism, we add fracture detail, incorporating
particle damage-time
to inform localised perturbation of the crack surface with artistic control. We evaluate our method with numerous examples and comparisons, showing that it produces a breadth of brittle material fracture effects and with low simulation resolution to require much less time compared to fully elastodynamic simulations.
On Optimizing Transaction Fees in Bitcoin using AI: Investigation on Miners Inclusion Pattern
Authors: Tedeschi Enrico , Nordmo Tor-Arne S. , Johansen Dag , Johansen Håvard D.
Published: April 2022

The transaction-rate bottleneck built into popular proof-of-work (PoW)-based cryptocurrencies, like Bitcoin and Ethereum, leads to fee markets where transactions are included according to a first-price auction for block space. Many attempts have been made to adjust and predict the fee volatility, but even well-formed transactions sometimes experience unexpected delays and evictions unless a substantial fee is offered. In this article, we propose a novel transaction inclusion model that describes the mechanisms and patterns governing miners decisions to include individual transactions in the Bitcoin system. Using this model we devise a Machine Learning (ML) approach to predict transaction inclusion. We evaluate our predictions method using historical observations of the Bitcoin network from a five month period that includes more than 30 million transactions and 120 million entries. We find that our Machine Learning (ML) model can predict fee volatility with an accuracy of up to 91%. Our findings enable Bitcoin users to improve their fee expenses and the approval time for their transactions.
FELIX: A Ferroelectric FET Based Low Power Mixed-Signal In-Memory Architecture for DNN Acceleration
Authors: Soliman Taha , Laleni Nellie , Kirchner Tobias , Müller Franz , Shrivastava Ashish , Kämpfe Thomas , Guntoro Andre , Wehn Norbert
Published: April 2022

Today, a large number of applications depend on deep neural networks (DNN) to process data and perform complicated tasks at restricted power and latency specifications. Therefore, processing-in-memory (PIM) platforms are actively explored as a promising approach to improve the throughput and the energy efficiency of DNN computing systems. Several PIM architectures adopt resistive non-volatile memories as their main unit to build crossbar-based accelerators for DNN inference. However, these structures suffer from several drawbacks such as reliability, low accuracy, large ADCs/DACs power consumption and area, high write energy, and so on. In this article, we present a new mixed-signal in-memory architecture based on the bit-decomposition of the multiply and accumulate (MAC) operations. Our in-memory inference architecture uses a single FeFET as a non-volatile memory cell. Compared to the prior work, this system architecture provides a high level of parallelism while using only 3-bit ADCs. Also, it eliminates the need for any DAC. In addition, we provide flexibility and a very high utilization efficiency even for varying tasks and loads. Simulations demonstrate that we outperform state-of-the-art efficiencies with 36.5 TOPS/W and can pack 2.05 TOPS with 8-bit activation and 4-bit weight precision in an area of 4.9 mm
2
using 22 nm FDSOI technology. Employing binary operation, we obtain 1169 TOPS/W and over 261 TOPS/W/mm
2
on system level.
Ember
Authors: Gregertsen Kristoffer Nyborg
Published: April 2022

This paper describes the Ember library for high-integrity embedded robotics and GNC applications developed in SPARK 2014 with formal verification. The library is based on generic packages and includes functionality as linear algebra, complex numbers, quaternions, and kinematics. Preliminary test results for linear algebra performance are very promising.
More Ada in non-Ada systems
Authors: Marriott A , Maurer U
Published: April 2022

This article is based on the industrial presentation "More Ada in non-Ada systems" which was given at the 2021 Ada-Europe virtual conference.

The presentation was an update to the presentation given at the Ada-Europe 2018 conference in Lisbon entitled "Using Ada in non-Ada systems" and that was subsequently published in the Ada User Journal [1].

The work used GCC 7.4.1 built by AdaCore and made available as part of their 2019 Windows hosted GNAT for ARM GPL community distribution. The GNAT sources referred to in the presentation were also obtained from this distribution.
Application of Intraoperative Optical Coherence Tomography Technology in Anterior Segment Surgery
Authors: Han Sang Beom , Liu Yu-Chi , Mohamed-Noriega Karim , Mehta Jodhbir S.
Published: April 2022

The use of optical coherence tomography (OCT) technology in anterior segment diseases allows for precise assessment of the changes following anterior segment surgery. Advances in microscope-integrated OCT systems have allowed the utilization of intraoperative OCT (iOCT) in anterior segment surgeries, i.e., cornea, cataract, and refractive surgery. iOCT has enabled real-time precise visualization of anterior segment tissues as well as interactions between surgical instruments and ocular tissue; thus, the device can facilitate surgical procedures and provide valuable information for decision-making during anterior segment surgeries. In this review, the authors will introduce studies regarding the development of iOCT technology and its application in various anterior segment surgeries. Multiple studies have shown the efficacy of the iOCT for intraoperative assistance and guidance, suggesting the potential of the device for optimizing the surgical outcomes after cornea, cataract, and refractive surgery.
Study on Environmental Effects Induced by Quasirectangle Shield Tunnelling with Analytical Stiffness Matrix
Authors: Xu Jianguo , Miao Fengyang , Kou Lei , Zhang Jinpeng
Published: April 2022

During the quasirectangle shield tunnelling, the soil around the tunnel is inevitably disturbed which results in different degrees of additional stresses and displacement of the soil. In this paper, the environmental effects caused by the construction of quasirectangle shield are analyzed by the analytical stiffness matrix method, focusing on the law of the additional stress field and the deformation of the multilayered soil induced by the construction of a quasirectangle shield. The results show that the additional stresses field has localized characteristics around the quasirectangle shield. The further away from the excavation face, the smaller the stress is. Also, shell friction and synchronous grouting pressure have a significantly greater influence on the additional stress field. Finally, the horizontal settlement groove of the quasirectangle shield is roughly symmetrical and parabolic along the tunnel axis, with a groove width range of about 20m. Synchronous grouting pressure has a greater effect on longitudinal ground deformation.