bluuebunny/crossref_metadata_2025 huggingface dataset:
How Microbiome Composition Correlates with Biochemical Changes during Sauerkraut Fermentation: a Focus on Neglected Bacterial Players and Functionalities
Authors: Tlais Ali Zein Alabiden , Lemos Junior Wilson José Fernandes , Filannino Pasquale , Campanaro Stefano , Gobbetti Marco , Di Cagno Raffaella
Published: June 2022

Our study was not limited to describe the succession pattern of the microbial community during sauerkraut fermentation, but also revealed how some neglected bacterial players belong to the core species during sauerkrauts processing, especially at low temperature. Such species might have a role as potential starters to optimize the fermentation processes and to obtain sauerkrauts with improved and standardized nutritional and sensory features.
Evaluation of change in emergency care knowledge and skills among front-line healthcare providers in Ukraine with the Basic Emergency Care course: a pretest/post-test study
Authors: Kivlehan Sean M , Allen Amy , Viun Olha , Makarov Dmitry A , Schnorr Daniel , Patel Sonny , Ryzhenko Sergii A , Pham Phuong , Erickson Timothy B
Published: June 2022

Objective

Evaluate the change in participant emergency care knowledge and skill confidence after implementation of the WHO-International Committee of the Red Cross (ICRC) Basic Emergency Care (BEC) course.

Design

Pretest/post-test quasi-experimental study.

Setting

Mechnikov Hospital in Dnipro, Ukraine.

Participants

Seventy-nine participants engaged in the course, of whom 50 (63.3%) completed all assessment tools. The course was open to healthcare providers of any level who assess and treat emergency conditions as part of their practice. The most common participant profession was resident physician (24%), followed by health educator (18%) and prehospital provider (14%).

Interventions

The 5-day WHO-ICRC BEC course.

Primary and secondary outcome measures

Change in pre-course and post-course knowledge and skill confidence assessments. Open-ended written feedback was collected upon course completion and analysed for common themes.

Results

Participant knowledge assessment scores improved from 19 (IQR 15–20) to 22 (IQR 19–23) on a 25-point scale (p<0.001). Participant skill confidence self-assessment scores improved from 2.5 (IQR 2.1–2.8) to 2.9 (IQR 2.5–3.3) on a 4-point scale (p<0.001). The most common positive feedback themes were high-quality teaching and useful skill sessions. The most common constructive feedback themes were translation challenges and request for additional skill session time.

Conclusions

This first implementation of the WHO-ICRC BEC course for front-line healthcare providers in Ukraine was successful and well received by participants. This is also the first report of a BEC implementation outside of Africa and suggests that the course is also effective in the European context, particularly in humanitarian crisis and conflict settings. Future research should evaluate long-term knowledge retention and the impact on patient outcomes. Further iterations should emphasise local language translation and consider expanding clinical skills sessions.
Common protocol for validation of the QCOVID algorithm across the four UK nations
Authors: Kerr Steven , Robertson Chris , Nafilyan Vahe , Lyons Ronan A , Kee Frank , Cardwell Christopher R , Coupland Carol , Lyons Jane , Humberstone Ben , Hippisley-Cox Julia , Sheikh Aziz
Published: June 2022

Introduction

The QCOVID algorithm is a risk prediction tool for infection and subsequent hospitalisation/death due to SARS-CoV-2. At the time of writing, it is being used in important policy-making decisions by the UK and devolved governments for combatting the COVID-19 pandemic, including deliberations on shielding and vaccine prioritisation. There are four statistical validations exercises currently planned for the QCOVID algorithm, using data pertaining to England, Northern Ireland, Scotland and Wales, respectively. This paper presents a common procedure for conducting and reporting on validation exercises for the QCOVID algorithm.

Methods and analysis

We will use open, retrospective cohort studies to assess the performance of the QCOVID risk prediction tool in each of the four UK nations. Linked datasets comprising of primary and secondary care records, virological testing data and death registrations will be assembled in trusted research environments in England, Scotland, Northern Ireland and Wales. We will seek to have population level coverage as far as possible within each nation. The following performance metrics will be calculated by strata: Harrell’s C, Brier Score, R2 and Royston’s D.

Ethics and dissemination

Approvals have been obtained from relevant ethics bodies in each UK nation. Findings will be made available to national policy-makers, presented at conferences and published in peer-reviewed journal.
Access to mass media and teenage pregnancy among adolescents in Zambia: a national cross-sectional survey
Authors: Sserwanja Quraish , Sepenu Abigail Sitsope , Mwamba Daniel , Mukunya David
Published: June 2022

Objective

Teenage pregnancies and childbirths are associated with negative health outcomes. Access to health information enables adolescents to make appropriate decisions. However, the relationship between access to health information through mass media and teenage pregnancy has not received much attention in existing literature. We therefore examined the association between access to mass media and teenage pregnancy in Zambia.

Design

Cross-sectional.

Setting

Zambia.

Participants

Weighted sample of 3000 adolescents aged 15–19 years.

Outcome measure

Teenage pregnancy that included adolescents who were currently pregnant or had had an abortion or had given birth in the last 5 years preceding the survey.

Results

Out of 3000 adolescents, 897 (29.9%, 95% CI: 28.1% to 31.3%) were pregnant or had ever been pregnant. Majority of the adolescents resided in rural areas (55.9%) and had secondary education (53.6%). Adolescents who had exposure to internet, newspapers or magazines, radio and television were 10.5%, 22.6%, 43.1% and 43.1%, respectively. Adolescents who had daily access to newspapers or magazines (adjusted OR (AOR): 0.33, 95% CI: 0.13 to 0.82) or using internet (AOR: 0.54, 95% CI: 0.30 to 0.95) were less likely to be pregnant or to have had a pregnancy compared with those with no access to newspapers and internet, respectively.

Conclusion

Our study suggests that internet use and reading of newspapers or magazines may trigger behavioural change as an effective approach to reducing teenage pregnancy. Behavioural change communicators can implement mass media campaigns using newspapers, magazines and the internet to publicise adolescent health messages that can encourage adolescents to adopt healthy behaviours and prevent teenage pregnancies.
Natural population cohort study on long-lived adults: West China longevity and ageing procedure (WCLAP)
Authors: Wu Xiaochu , Zhang Tianyao , Zhang Yan , She Yan , Wang Li , Gao Yanling , Deng Yiping , Chen Meijuan , He Yan , Chen Xiaoyan , Hao Qiukui , Yue Jirong , Dong Birong
Published: June 2022

Purpose

The West China longevity and ageing procedure (WCLAP) cohort study aims to provide guidance for older adults in western China with the aim of improving quality of life, reducing the burden of family care, summarising the characteristics of longevity lifestyles, building a Chinese-longevity-population biobank and exploring the mechanisms underlying population ageing.

Participants

Since the establishment of the WCLAP research baseline in 2018, a population of 1537 adults aged 80 years and above, living in the community, have been enrolled in the programme as research participants. Of these, 231 are aged 100 years and above. Participants are followed up every year.

Finding to data

WCLAP data are collected in five hospital research subcentres strategically located adjacent to the national ‘Longevity Townships’ of Chengdu Ziyang, Leshan, Yibin and Pengshan. Data collection included a comprehensive assessment of the participant’s health (including physical, psychological, social and common chronic disease assessments), instrumental tests (body composition and muscle percentage) and the collection of biomedical-biobank samples (include blood, urine, faeces, hair and urine).

Future plans

Through the annual cohort follow-up, survival-related information is collected at a group level. Analysis of biological samples facilitates biological characterisation at the microscopic level through proteomics, metabolomics, genomics and other techniques. Baseline data, group-level follow-up data and microbiological examination data are integrated together to provide an evaluation tool, exploring sarcopenia, disability, dementia, caregiver burden, ageing biomarkers and other influencing factors.

Trial registration numbers

2018-463; ChiCTR1900020754.
Turning green: the impact of changing to more eco-friendly respiratory healthcare – a carbon and cost analysis of Dutch prescription data
Authors: ten Have Pieter , van Hal Peter , Wichers Iris , Kooistra Johan , Hagedoorn Paul , Brakema Evelyn A , Chavannes Niels , de Heer Pauline , Ossebaard Hans C
Published: June 2022

Objectives

Dry powder inhalers (DPIs) and soft mist inhalers have a substantially lower global warming potential than pressurised metered-dose inhalers (pMDIs). To help mitigate climate change, we assessed the potential emission reduction in CO2 equivalents when replacing pMDIs by non-propellant inhalers (NPIs) in Dutch respiratory healthcare and estimated the associated cost.

Design

We performed a descriptive analysis of prescription data from two national databases of two independent governmental bodies. First, we calculated the number of patients with chronic obstructive pulmonary disease (COPD) and asthma that were using inhalation medication (2020). Second, we calculated the number and total of daily defined doses of pMDIs and NPIs including DPIs and soft mist inhalers, as well as the number of dispensed spacers per patient (2020). Third, we estimated the potential emission reduction in CO2 equivalents if 70% of patients would switch from using pMDIs to using NPIs. Fourth, we performed a budget impact analysis.

Setting

Dutch respiratory healthcare.

Primary and secondary outcome measures

The carbon footprint of current inhalation medication and the environmental and financial impact of replacing pMDIs with NPIs.

Results

In 2020, 1.4 million patients used inhalers for COPD or asthma treatment. A total of 364 million defined daily doses from inhalers were dispensed of which 49.6% were dispensed through pMDIs. We estimated that this could be reduced by 70% which would lead to an annual reduction in greenhouse gas emission of 63 million kg.CO2 equivalents saving at best EUR 49.1 million per year.

Conclusions

In the Netherlands, substitution of pMDIs to NPIs for eligible patients is theoretically safe and in accordance with medical guidelines, while reducing greenhouse gas emission by 63 million kg.CO2 equivalents on average and saving at best EUR 49.1 million per year. This study confirms the potential climate and economic benefit of delivering a more eco-friendly respiratory care.
Acupuncture for patients with type 2 diabetes mellitus with dry eye: protocol for a systematic review and meta-analysis
Authors: Wei Juan , Wei Qingbo , Li Ting , Xie Zhouyu , Xu Xin , Bian Xiangyu , Wu Yunchuan
Published: June 2022

Introduction

The global incidence of patients with type 2 diabetes mellitus (T2DM) with dry eye is increasing annually, which imposes additional healthcare costs and financial burden on families and societies. In clinical practice, artificial tears are often used for symptomatic treatment, but these can only relieve the symptoms of discomfort. Acupuncture is a widely used alternative therapy. Indeed, randomised trials have found that acupuncture confers a definite therapeutic effect on patients with T2DM with dry eye. However, systematic reviews on the effectiveness and safety of acupuncture are lacking, therefore this systematic review aims to evaluate the effectiveness and safety of acupuncture for T2DM with dry eye.

Methods and analysis

Four English databases (PubMed, Cochrane Library, Embase and Ovid), three Chinese databases (China National Knowledge Infrastructure, Wanfang, Chonqing VIP Information), three Japanese databases (Japan Science, Technology Agency and Japan Medical Abstracts Society) and three Korean databases (Korean Medical database, Oriental Medicine Advanced Searching Integrated System and Research Information Service System) will be searched for reports published between 1 January 2007 and 1 October 2021. Only randomised controlled trials will be included, and language or publication dates will not be restricted. Two researchers will independently extract, manage and analyse data. The primary outcomes will include Schirmer’s I test, breakup time, corneal fluorescein staining and ocular surface disease index scores. Secondary results will include visual analogue scale scores for ocular symptoms and any adverse events related to acupuncture. We will use Review Manager V.5.4 for the meta-analysis. The risk of bias will be independently assessed using Cochrane’s ‘risk of bias’ tool.

Ethics and dissemination

Ethical approval will not be required since raw data will not be collected or generated. Our findings will be disseminated through peer-reviewed journal.

PROSPERO registration number

CRD42021271891.
Positive end-expiratory pressure and risk of postoperative pulmonary complications in patients living at high altitudes and undergoing surgery at low altitudes: a single-centre, retrospective observational study in China
Authors: Shang Kaixi , Xia Zongjing , Ye Xiaoli , Li Zhuoning , Gong Chongcong
Published: June 2022

Objectives

To examine whether a high positive end-expiratory pressure (PEEP ≥5 cmH2O) has a protective effect on the risk of postoperative pulmonary complications (PPCs) in a cohort of patients living at high altitudes and undergoing general anaesthesia.

Design

Retrospective, observational study.

Setting

A tertiary hospital in China.

Participants

Adult Tibetan patients living at high altitudes (≥3000 m) and who went to the low-altitude plain to undergo non-cardiothoracic surgery under general anaesthesia, from January 2018 to April 2020.

Measurements

This study included 1905 patients who were divided according to the application of an intraoperative PEEP: low PEEP (<5 cmH2O, including 0 cmH2O) or high PEEP (≥5 cmH2O). The primary outcome was a composite of PPCs within the first 7 postoperative days. The secondary outcomes included reintubation and unplanned intensive care unit (ICU) admission within the first 7 postoperative days and total hospital stays (day).

Results

The study included 1032 patients in the low PEEP group and 873 in the high PEEP group. There were no differences in the incidence of PPCs between the high and low PEEP groups (relative risk (RR) 0.913; 95% CI 0.716 to 1.165; p=0.465). After propensity score matching, 643 patients remained in each group, and the incidence of PPCs in the low PEEP group (18.0%) was higher than in the high PEEP group (13.7%; RR 0.720; 95% CI 0.533 to 0.974; p=0.033). There were no differences in the incidence of reintubation, unplanned ICU admission or hospital stays. The risk factors of PPCs derived from multiple regression showed that the application of >5 cmH2O PEEP during intraoperative mechanical ventilation was associated with a significantly lower risk of PPCs in patients from a high altitude (OR=0.725, 95% CI 0.530 to 0.992; p=0.044).

Conclusions

The application of PEEP ≥5 cmH2O during intraoperative mechanical ventilation in patients living at high altitudes and undergoing surgery at low altitudes may be associated with a lower risk of PPCs. Prospective longitudinal studies are needed to further investigate perioperative lung protection ventilation strategies for patients from high altitudes.

Trial registration number

Chinese Clinical Trial Registry (ChiCTR2100044260).
On the road to universal coverage of postnatal care: considerations for a targeted postnatal care approach for at-risk mother–baby dyads in low-income and middle-income countries informed by a consultation with global experts
Authors: Muriuki Angela , Yahner Melanie , Kiragu Michael , de Graft-Johnson Joseph , Izulla Preston
Published: June 2022

Introduction

The potential of timely, quality postnatal care (PNC) to reduce maternal and newborn mortality and to advance progress toward universal health coverage (UHC) is well-documented. Yet, in many low-income and middle-income countries, coverage of PNC remains low. Risk-stratified approaches can maximise limited resources by targeting mother–baby dyads meeting the evidence-based risk criteria which predict poor postnatal outcomes.

Objectives

To review evidence-based risk criteria for identification of at-risk mother–baby dyads, drawn from a literature review, and to identify key considerations for their use in a risk-stratified PNC approach.

Design/setting/participants

A virtual, semi-structured group discussion was conducted with maternal and newborn health experts on Zoom. Participants were identified through purposive sampling based on content and context expertise.

Results

Seventeen experts, (5 men and 12 women), drawn from policymakers, implementing agencies and academia participated and surfaced several key themes. The identified risk factors are well-known, necessitating accelerated efforts to address underlying drivers of risk. Risk-stratified PNC approaches complement broader UHC efforts by providing an equity lens to identify the most vulnerable mother–baby dyads. However, these should be layered on efforts to strengthen PNC service provision for all mothers and newborns. Risk factors should comprise context-relevant, operationalisable, clinical and non-clinical factors. Even with rising coverage of facility delivery, targeted postnatal home visits still complement facility-based PNC.

Conclusion

Risk-stratified PNC efforts must be considered within broader health systems strengthening efforts. Implementation research at the country level is needed to understand feasibility and practicality of clinical and non-clinical risk factors and identify unintended consequences.
Value of robotic surgery simulation for training surgical residents and attendings: a systematic review protocol
Authors: Howard Kathryn K , Makki Hussein , Novotny Nathan M , Mi Misa , Nguyen Ngan
Published: June 2022

Introduction

Robotic surgery is a method of minimally invasive surgery performed through small incisions using a remote robotic console. Surgical residents and attendings participate in simulation training to be able to effectively perform robotic surgery using wet labs, dry labs and virtual reality platforms. Our objective is to identify the effectiveness of robotic simulation on novice robotic surgeons. This review will answer our review question: To what extent are robotic simulations for training novice robotic general surgery residents and attendings associated with improved outcomes in comparison with no simulation training?

Methods and analysis

A comprehensive search of PubMed, Embase, the Cochrane Library and Web of Science was performed. The studies were then determined to meet initial screening criteria by one individual for abstract and title with full text screening performed by two authors independently and in duplicate. Narrative themes will be collected, analysed and summarised where possible.

Ethics and dissemination

There is no Institutional Review Board approval required given that the work is carried out on previously published papers. The final manuscript and results will be presented and published at an academic conference and peer -reviewed journal.

PROSPERO registration number

CRD42021274090.
High training volume is associated with increased prevalence of non-allergic asthma in competitive cross-country skiers
Authors: Mäki-Heikkilä Rikhard , Karjalainen Jussi , Parkkari Jari , Huhtala Heini , Valtonen Maarit , Lehtimäki Lauri
Published: June 2022

Background

Cross-country skiers have a high prevalence of asthma, but its phenotypes and association with success in competitions are not known.

Objective

To investigate, by means of a postal survey, the relative proportions of allergic and non-allergic asthma in competitive cross-country skiers compared with the general population, to study how performance level and training volume are related to asthma and its type and to assess the possible risk factors for allergic and non-allergic asthma in competitive skiers.

Methods

All Finnish cross-country skiers enrolled in the largest national competitions in winter 2019 (n=1282), and a random sample (n=1754) of the general population of the same age were sent a postal questionnaire. The response rate was 27.4% (n=351) for skiers and 19.5% (n=338) for the controls. International Ski Federation (FIS) ranking points measured the level of success in skiers. Asthma was defined as self-reported, physician-diagnosed asthma. Asthma was considered allergic if associated with doctor-diagnosed allergy, and exposure to allergens provoked asthma symptoms.

Results

The prevalence of asthma was higher in skiers than in the controls (25.9% vs 9.2%, p<0.001), and it was the highest (56.1%) in the most successful quartile of skiers. Asthma was more often non-allergic in skiers than in the controls (60.1% vs 38.7%, p=0.036). Being a skier came with a higher risk for non-allergic (OR 5.05, 95% CI 2.65 to 9.61) than allergic asthma (OR 1.92, 1.08–3.42). Using multivariable regression analysis, training volume was associated with non-allergic asthma, while age, family history of asthma and allergic rhinitis were associated with allergic asthma.

Conclusion

The prevalence of asthma is the highest in the most successful cross-country skiers. The asthma in skiers is mostly non-allergic compared with the general population of the same age. The most important risk factor for non-allergic asthma in skiers is high training volume.
Impact of low-dose acetylsalicylic acid on pregnancy outcome in systemic lupus erythematosus: results from a multicentre study
Authors: Tani Chiara , Zucchi Dina , Haase Isabell , Gerosa Maria , Larosa Maddalena , Cavagna Lorenzo , Bortoluzzi Alessandra , Crisafulli Francesca , Mucke Johanna , Strigini Francesca A L , Baglietto Laura , Fornili Marco , Monacci Francesca , Elefante Elena , Erra Roberta , Bellis Elisa , Padovan Melissa , Andreoli Laura , Coletto Lavinia Agra , Zanframundo Giovanni , Govoni Marcello , Iaccarino Luca , Tincani Angela , Doria Andrea , Fischer-Betz Rebecca , Mosca Marta
Published: June 2022

Objective

It is still a matter of debate whether low-dose acetylsalicylic acid (LDASA) should be prescribed to all patients with SLE during pregnancy. This study aimed at investigating the impact of LDASA on pregnancy outcomes in patients with SLE without history of renal involvement and without antiphospholipid antibodies (aPL).

Methods

This is a retrospective analysis of prospectively monitored pregnancies at seven rheumatology centres. Previous/current renal involvement and aPL positivity were the exclusion criteria. Adverse pregnancy outcome (APO) is the composite outcome of the study and included proteinuric pre-eclampsia, preterm delivery <37 weeks, small-for-gestational age infant, low birth weight <2500 g, intrauterine growth restriction and intrauterine fetal death after 12 weeks of gestation of a morphologically normal fetus.

Results

216 pregnancies in 187 patients were included; 82 pregnancies (38.0%) were exposed to LDASA treatment. No differences in terms of age at conception, disease duration, clinical manifestations, comorbidities and disease flare during pregnancy were observed between patients taking LDASA and those who did not take LDASA during pregnancy. APO was observed in 65 cases (30.1%), including 13 cases (6.1%) of pre-eclampsia. The incidence of all complications was similar in the two groups. However, it is interesting to note that pre-eclampsia had lower frequency in patients taking LDASA versus those not taking LDASA (2.4% vs 8.3%, p=0.14).

Conclusions

In pregnant patients with SLE without renal involvement and were aPL-negative, there is a low risk of severe obstetric complications, such as early pre-eclampsia. LDASA treatment does not provide a statistically significant advantage over these complications. However, a careful individual risk–benefit balance is warranted.
High prevalence of chondrocalcinosis and frequent comorbidity with calcium pyrophosphate deposition disease in patients with seronegative rheumatoid arthritis
Authors: Krekeler Martin , Baraliakos Xenofon , Tsiami Styliani , Braun Juergen
Published: June 2022

Background

The crystal-induced calcium pyrophosphate deposition disease (CPPD) clinically appearing as pseudogout differs from the mere radiographic finding of chondrocalcinosis (CC) but may cause symptoms resembling rheumatoid arthritis (RA).

Objective

To study the prevalence of CPPD and CC in rheumatic diseases focusing on differences between seropositive and seronegative RA.

Patients and methods

In a retrospective study design, we analysed records and radiographs of consecutive new patients presenting to our centre between January 2017 and May 2020. 503 patients were identified based on expert diagnoses: 181 with CPPD, 262 with RA, 142 seropositive (54.2%) and 120 seronegative RA, gout (n=30) and polymyalgia rheumatica (n=30), mean symptom duration <1 year in almost all patients.

Results

The majority of patients had only one rheumatological diagnosis (86.9%). Most patients with CPPD (92.6%) had radiographic CC, primarily in the wrists. The prevalence of CC was higher in seronegative (32.3%) than in seropositive RA (16.6%), respectively (p<0.001). Patients with CPPD were older (p<0.001) and had acute attacks more frequently than patients with RA (p<0.001), who had symmetric arthritis more often (p=0.007). The distribution pattern of osteoarthritic changes in radiographs of hands and wrists differs between patients with RA and CPPD. CC was present in more than one joint in 73.3% of patients with CPPD, 9.6% with seropositive and 18.7% with seronegative RA.

Discussion

CPPD and CC were more frequent in seronegative versus seropositive RA. Symmetry of arthritis and acuteness of attacks differentiated best between CPPD and RA but localisation of joint involvement did not. Co-occurrence of both diseases was frequently observed.
Influence of freeze–thaw on the stability of road cut slopes—a case study in the Indian Himalayan region
Authors: Sardana Sahil , Sinha Rabindra Kumar , Verma A.K. , Jaswal Mamta , Singh T.N.
Published: June 2022

The rock slopes in the Indian Himalayan region are exposed to recurrent freeze–thaw (FT). FT testing (0–30 FT cycles) was carried out in the laboratory on the rock samples collected from the Indian Himalayan region. The result shows a reduction of 27%–39% in rock strength. Microscopic damages were observed in SEM images. Further, a three-dimensional numerical analysis was performed to evaluate the stability and corroborate the results with the field observations. FT conditioning results reveal a 10%–39% decrease in the safety factor for rock slopes.
Spontaneous symmetry breakings in the singlet scalar Yukawa model within the auxiliary field method
Authors: Nogueira A. A. , Braghin F. L.
Published: June 2022

The aim of this work is to investigate the occurrence of two different spontaneous symmetry breakings at two levels of the description of fermion-scalar field model, by means of a set of gap equations and with a background field effective action. For that, we consider the Yukawa model, as a toy model for interactions between nonmassive fermions intermediated by a self-interacting real scalar field. This model has at stake two symmetries at the classical level that, as we know, might be spontaneously or dynamically broken with mass generation for the particles. The auxiliary field method is considered and it produces coupled renormalized gap equations. The effective action is then written with quantum contributions by the external background field method. We brought to light how the renormalization procedure affects the physical gaps, investigate its properties, and discuss the connection between the auxiliary fields not only to define composite states but also to compute the effective action.
Accelerating binary black hole system
Authors: Beesham Aroonkumar
Published: June 2022

Recently, by the end of their second observing run, advanced LIGO and Virgo have detected some binary black hole mergers. In this paper, we show that the acceleration of black holes around each other causes the emergence of two Rindler space–times. The parameters of the black hole in each region change in opposite order to the parameters of the black hole in the other region. Also, the acceleration has a direct relation to the black hole entropies and their observed redshifts.
A Novel Scrambling Method Based on Coupling Mode Switching Strategy for Digital Chaos
Authors: Zhou Peizhao , Wei Shengfei
Published: June 2022

The dynamical degradation of digital chaos brings serious defects to chaos-based digital systems and greatly restricts its applications. In this paper, we first discuss the integer logistic map (ILM) and calculate its cycle lengths under different precision. Then, a novel scrambling method based on coupling mode switching (CMS) strategy named CMSSM is proposed to enhance the chaotic features of digital chaos. Following the selection principles, we use three coupling mode candidates to construct 3CMSSM. Theoretical analysis shows that the output cycle length of 3CMSSM is three times that of scrambling methods used in single coupling mode (SCM) strategy. Numerical simulations are carried out to demonstrate the desirable statistical and dynamical properties of scrambled ILM. Finally, we design a (pseudo-random number generator) PRNG based on 3CMSSM. Both results of statistical test suites NIST SP800-22 and TestU01 show that the suggested PRNG has highly credible randomness compared to other algorithms.
Numerical Sensitivity Analysis and Hardware Verification of a Transiently-Chaotic Attractor
Authors: Sayed Wafaa S. , Mohamed Sara M. , Elwakil Ahmed S. , Said Lobna A. , Radwan Ahmed G.
Published: June 2022

We introduce a new chaotic system with nonhyperbolic equilibrium and study its sensitivity to different numerical integration techniques prior to implementing it on an FPGA. We show that the discretization method used in numerically integrating the set of differential equations in MATLAB and Mathematica does not yield chaotic behavior except when a low accuracy Euler method is used. More accurate higher-order numerical algorithms (such as midpoint and fourth-order Runge–Kutta) result in divergence in both MATLAB and Mathematica (but not Python), which agrees with the divergence observed in an analog circuit implementation of the system. However, a fixed-point digital FPGA implementation confirms the chaotic behavior of the system using Euler and fourth-order Runge–Kutta realizations. Therefore, the increased sensitivity of chaotic systems with nonhyperbolic equilibrium should be carefully considered for reproducibility.
A Discrete Saccadic Model and Bursting
Authors: Mousavinejad F. S. , Fatehi Nia M.
Published: June 2022

One of the eye movements is the saccade, which has led to the introduction of the saccadic model. This study is based on the part of the saccadic model, which means the burst neurons and resettable integrator model. The principal limitation of the original model is the lack of differentiability at the equilibrium point. By using the Naka–Rushton function, we introduce a new model in place of the original one, so that the equilibrium point of the system becomes a differentiable point in the modified model. Our focus in this work is to investigate the fundamental properties of the discrete model of our novel system. We apply the forward Euler method to transform the new model to a discrete model. With the utilization of the center manifold theory, we describe some of its dynamical features, such as stability, instability, and bifurcation at a fixed point. Finally, both analytical and numerical simulations are used to continue investigating the period-doubling bifurcation according to the numerical parameters in the saccadic model.
Systematic Development of Cumulative Complexity Index for Investment Casting
Authors: Maheta Nikunj , Sata Dr Amit
Published: June 2022

Investment casting is usually employed for producing industrial castings for different sectors including aerospace, automobile, bio-medical, chemical, defense and many more. Frequently, decision to manufacture any industrial component using investment casting process is mainly driven by many factors associated with geometry, desired features as well as manufacturability of industrial components. In this work, five-layered hierarchical structure-based novel Cumulative Complexity Index (CCI) has been developed for making appropriate decision to select investment casting process for manufacturing any industrial component. Top layer is comprised of CCI that is further categorized into three categories of Complexity Index (CI) including characteristics of geometry characteristics, desired features and manufacturability of an industrial component. The CIs are categorized into various 19 elements and further into 52 attributes. These attributes with 212 meta-attributes are employed to compute CCI (in the scale from 0 to 100). As the value of CCI is higher, complexity involved in manufacturing industrial component using investment casting is higher. The proposed concept of CCI is tested on different industrial case studies, and found very useful in making decision to select investment casting process for manufacturing those industrial components. This can be easily embedded with any existing tool on design for casting.
Combined Technology Selection Model for Digital Transformation in Manufacturing: A Case Study From the Automotive Supplier Industry
Authors: Erbay Hasan , Yıldırım Nıhan
Published: June 2022

Among generic technology management activities, rapid technology identification and selection stand as the significant determinants of technology adoption success in the digital transformation era. Especially for manufacturing SMEs in developing countries, rapid digital technologies are critical since they struggle to protect their competitiveness in global value chains threatened by digitalization. Previous studies introduce various multi-criteria decision-making model-based approaches to identify and select appropriate manufacturing technologies. However, these approaches were relatively rigid and required an advanced understanding of the technology for criteria and alternative settings and evaluation. Decision-makers need more flexible and scalable contextual frameworks for technology selection in digitalization. Since digital technologies offer both benefits and challenges, the decision-making models should reflect this dialectic nature of Industry 4.0 adoption and contextually optimize their decisions by combining multiple quantitative methods for technology identification and selection. Besides, case studies on digital technology selection are rare in manufacturing SMEs from developing country context in the literature. In this context, this study proposes a technology selection framework that utilizes the three dimensions (industry 4.0 technologies, benefits, and challenges) and combines AHP with a QFD-inspired intervention matrix and an optimization model by Mixed Integer Programming (MIP). The proposed model is validated with a case study from the automotive supplier industry in Turkey with the data provided from interviews and a Delphi survey with 11 experts from the digitalization value chain of the selected industry. Case study results revealed that the highest benefits of industry 4.0 lie in process/quality efficiency improvement and reduced inventory. At the same time, data analytics and sensor technologies occurred as the most critical tools. Significant challenges of digital technology adoption are insufficient expert know-how and budget constraints.
Okay Google, Good to Talk to You… Examining the Determinants Affecting Users’ Behavioral Intention for Adopting Voice Assistants: Does Technology Self-Efficacy Matter?
Authors: Ashrafi Dewan Mehrab , Easmin Rubina
Published: June 2022

This study investigates the impact of attitude and trust on the behavioral intention of adopting artificial intelligence (AI)-based voice-assistant services through the integration of parasocial relationship theory (PSR) and human–computer interaction (HCI) theory. Employing a deductive approach, partial least squares structural equation modeling (PLS-SEM) was performed to assess the proposed model based on 295 participants by using a purposive sampling method. Findings revealed that the functional components significantly impacted users’ attitudes, while social attributes, such as social cognition and electronic word of mouth (e-WOM), were revealed to be critical constituents in driving users’ trust. Moreover, technology self-efficacy (TSE) showed a moderating impact on the relationship between trust and behavioral intention to use voice-assistant services. Based on the findings, the study provides robust and meaningful insights for managers and designers to foster trust and form a positive attitude among the users. Additionally, the outcome of the study adds to the body of research on AI-based technology adoption and interactions by investigating the antecedents of trust and attitudes towards voice-assistant services.
Nonlinear Thermo-Electro-Mechanical Buckling of Higher-Order Shear Deformable Stiffened FG-GRC Laminated Plates
Authors: Nam Vu Hoai , Dong Dang Thuy , Doan Cao Van , Phuong Nguyen Thi
Published: June 2022

In this paper, a new improved smeared stiffener technique for the higher-order shear deformable anisotropic stiffeners is presented. The thermo-electro-mechanical nonlinear buckling response of functionally graded graphene reinforcement composite (FG-GRC) laminated plates subjected to the combination of external and axial compression loads in the thermal environment with the inverse piezoelectric effect of a piezoelectric layer is analytically considered. It is proposed that the FG-GRC laminated plates are stiffened by the FG-GRC laminated stiffener system in the longitudinal or transverse directions at the bottom surface and the piezoelectric layer are attached at the top surface. The distribution law of graphene is suitably designed to ensure the piecewise continuity of material. The nonlinear higher-order shear deformation plate theory (HSDPT) is employed to formulate the stability equation system. The stress function is introduced and Galerkin’s method is employed to achieve the algebraically nonlinear stability equation system. Then, the simple calculation procedure can be applied to solve the acquired equation systems, and the expressions of critical buckling loads and postbuckling load-deflection curves are presented in explicit forms. The numerical investigations validate the significant influences of temperature, material, laminated stiffeners, and geometrical features on the nonlinear thermo-electro-mechanical buckling behavior of FG-GRC laminated plates.
On closed and absolutely closed varieties of posemigroups
Authors: Bano Sakeena , Shah Aftab Hussain , Nabi Muneer
Published: June 2022

In this paper, we first show that the variety [Formula: see text] of posemigroups satisfying an identity [Formula: see text] is closed if it is [Formula: see text]-convex. Next, we show that inverse posemigroups satisfying an identity [Formula: see text] are absolutely closed. We also show that a convex variety of left [right] zero posemigroups is absolutely closed and finally [Formula: see text] is absolutely closed if so is [Formula: see text].
On the analytic structure of second-order non-commutative probability spaces and functions of bounded Fréchet variation
Authors: Diaz Mario , Mingo James A.
Published: June 2022

In this paper, we propose a new approach to the central limit theorem (CLT) based on functions of bounded Fréchet variation for the continuously differentiable linear statistics of random matrix ensembles which relies on a weaker form of a large deviation principle for the operator norm; a Poincaré-type inequality for the linear statistics; and the existence of a second-order limit distribution. This approach frames into a single setting many known random matrix ensembles and as a consequence, classical central limit theorems for linear statistics are recovered and new ones are established, e.g. the CLT for the continuously differentiable linear statistics of block Gaussian matrices. In addition, our main results contribute to the understanding of the analytical structure of second-order non-commutative probability spaces. On the one hand, they pinpoint the source of the unbounded nature of the bilinear functional associated to these spaces; on the other hand, they lead to a general archetype for the integral representation of the second-order Cauchy transform, [Formula: see text]. Furthermore, we establish that the covariance of resolvents converges to this transform and that the limiting covariance of analytic linear statistics can be expressed as a contour integral in [Formula: see text].
Singular Spectrum Analysis and Circulant Maximum Variance Frames
Authors: Bonenberger Christopher , Ertel Wolfgang , Schwenker Friedhelm , Schneider Markus
Published: June 2022

Singular spectrum analysis (SSA) is a powerful method that is frequently used in dynamical systems theory and time series analysis. However, the algorithm itself is only partially understood. In this paper, we tackle the problem of a thorough interpretation of the complete basic SSA algorithm. We point out the relationship between SSA and Fourier analysis (FA), linear filtering (LF), principal component analysis (PCA), and power spectrum density estimation (PSDE). The main contribution is a reformulation and comprehensive interpretation of SSA by means of a novel class of data-adaptive circulant frames. Based on this class of frames, we introduce a formalism for time series decomposition and reconstruction. This mathematical framework generalizes principle component analysis and SSA. We show that SSA, PCA, FA, LF, and PSDE can be found from special cases of the proposed frame structures. This way we are able to provide a formal description of SSA and its relationship to the aforementioned methods. Whilst previous approaches to the interpretation of SSA relied on approximations, we provide exact mathematical descriptions of the relation between the above-mentioned techniques.
Cross-border subsurface geology in the Atlantic Margin and the Barents Sea: an introduction
Authors: Chiarella Domenico , Archer Stuart Gordon , Howell John A. , Jackson Christopher A.-L. , Kombrink Henk , Patruno Stefano
Published: June 2022

Over the last 50 years, the North Sea and the Atlantic Margin and, more recently the Barents Sea, represented key study areas for academic and professionals interested in the exploration for and production of hydrocarbon from the Earth's subsurface. Nowadays, these areas may play a major role in the so-called ‘energy transition’, with the energy industry now seeking to reduce emissions related to hydrocarbon consumption, and leading the development of carbon capture and storage activities, such as the
Northern Light project
(
https://northernlightsccs.com
). Consequently, there is an increasing interest in advancing our knowledge regarding the stratigraphy, sedimentology and tectonic development of the North Sea, Atlantic Margin and Barents Sea with a cross-border approach.
A Multilingual Neural Coaching Model with Enhanced Long-term Dialogue Structure
Authors: Zorrilla Asier López , Torres M. Inés
Published: June 2022

In this work we develop a fully data driven conversational agent capable of carrying out motivational coaching sessions in Spanish, French, Norwegian, and English. Unlike the majority of coaching, and in general well-being related conversational agents that can be found in the literature, ours is not designed by hand-crafted rules. Instead, we directly model the coaching strategy of professionals with end users. To this end, we gather a set of virtual coaching sessions through a Wizard of Oz platform, and apply state of the art Natural Language Processing techniques. We employ a transfer learning approach, pretraining GPT2 neural language models and fine-tuning them on our corpus. However, since these only take as input a local dialogue history, a simple fine-tuning procedure is not capable of modeling the long-term dialogue strategies that appear in coaching sessions. To alleviate this issue, we first propose to learn dialogue phase and scenario embeddings in the fine-tuning stage. These indicate to the model at which part of the dialogue it is and which kind of coaching session it is carrying out. Second, we develop a global deep learning system which controls the long-term structure of the dialogue. We also show that this global module can be used to visualize and interpret the decisions taken by the the conversational agent, and that the learnt representations are comparable to dialogue acts. Automatic and human evaluation show that our proposals serve to improve the baseline models. Finally, interaction experiments with coaching experts indicate that the system is usable and gives rise to positive emotions in Spanish, French and English, while the results in Norwegian point out that there is still work to be done in fully data driven approaches with very low resource languages.
AdaTest: Reinforcement Learning and Adaptive Sampling for On-chip Hardware Trojan Detection
Authors: Chen Huili , Zhang Xinqiao , Huang Ke , Koushanfar Farinaz
Published: June 2022

This paper proposes AdaTest, a novel
adaptive test pattern generation
framework for efficient and reliable
Hardware Trojan (HT)
detection. HT is a backdoor attack that tampers with the design of victim
integrated circuits (ICs)
. AdaTest improves the existing HT detection techniques in terms of scalability and accuracy of detecting smaller Trojans in the presence of noise and variations. To achieve high trigger coverage, AdaTest leverages
Reinforcement Learning (RL)
to produce a diverse set of test inputs. Particularly, we
progressively
generate test vectors with high ‘reward’ values in an
iterative
manner. In each iteration, the test set is evaluated and adaptively expanded as needed. Furthermore, AdaTest integrates
adaptive sampling
to prioritize test samples that provide more information for HT detection, thus reducing the number of samples while improving the samples’ quality for faster exploration.

We develop AdaTest with a
Software/Hardware co-design
principle and provide an optimized on-chip architecture solution. AdaTest’s architecture minimizes the hardware overhead in two ways: (i) Deploying circuit emulation on programmable hardware to accelerate reward evaluation of the test input; (ii) Pipelining each computation stage in AdaTest by automatically constructing auxiliary circuit for test input generation, reward evaluation, and adaptive sampling. We evaluate AdaTest’s performance on various HT benchmarks and compare it with two prior works that use logic testing for HT detection. Experimental results show that AdaTest engenders up to two orders of test generation speedup and two orders of test set size reduction compared to the prior works while achieving the same level or higher Trojan detection rate.