bluuebunny/crossref_metadata_2025 huggingface dataset:
High Taxonomic Diversity in Ship Bilges Presents Challenges for Monitoring Microbial Corrosion and Opportunity To Utilize Community Functional Profiling
Authors: Wood J. L. , Neil W. C. , Wade S. A.
Published: July 2021

Microbially influenced corrosion (MIC) has been estimated to contribute 20 to 50% of the costs associated with corrosion globally. Diagnosis and monitoring of MIC are complex problems requiring knowledge of corrosion rates, corrosion morphology, and the associated microbiology to distinguish MIC from abiotic corrosion processes.
Unchaining mini
Bacillus
Strain PG10: Relief of FlgM-Mediated Repression of Autolysin Genes
Authors: van Tilburg Amanda Y. , Fülleborn Julius A. , Reder Alexander , Völker Uwe , Stülke Jörg , van Heel Auke J. , Kuipers Oscar P.
Published: July 2021

Reduction of the size of bacterial genomes is relevant for understanding the minimal requirements for cellular life as well as from a biotechnological point of view. Although the genome-minimized
Bacillus subtilis
strain PG10 displays several beneficial traits as a microbial cell factory compared to its parental strain, a defect at the final stage of cell division was introduced during the genome reduction process.
Complexity and Local Specificity of the Virome Associated with Tospovirus-Transmitting Thrips Species
Authors: Chiapello M. , Bosco L. , Ciuffo M. , Ottati S. , Salem N. , Rosa C. , Tavella L. , Turina M.
Published: July 2021

Harnessing the insect microbiome can result in new approaches to contain their populations or the damage they cause vectoring viruses of medical, veterinary, or agricultural importance. Persistent insect viruses are a neglected component of their microbiota.
Matrix Effects on the Delivery Efficacy of Bifidobacterium animalis subsp.
lactis
BB-12 on Fecal Microbiota, Gut Transit Time, and Short-Chain Fatty Acids in Healthy Young Adults
Authors: Ba Zhaoyong , Lee Yujin , Meng Huicui , Kris-Etherton Penny M. , Rogers Connie J. , Lewis Zachery T. , Mills David A. , Furumoto Emily J. , Rolon M. Laura , Fleming Jennifer A. , Roberts Robert F.
Published: July 2021

Bifidobacterium animalis
subsp.
lactis
BB-12 is a probiotic strain that has been used worldwide since 1985. It has commonly been delivered in fermented dairy products for perceived benefits associated with gut health and enhanced immune function.
Mild Cystic Fibrosis Lung Disease Is Associated with Bacterial Community Stability
Authors: Hampton Thomas H. , Thomas Devin , van der Gast Christopher , O’Toole George A. , Stanton Bruce A.
Published: July 2021

While much research supports a polymicrobial view of the CF airway, one in which the community is seen as the pathogenic unit, only controlled experiments using model bacterial communities can unravel the mechanistic role played by different communities. This report uses a large data set to identify a small number of communities as a starting point in the development of tractable model systems.
In Vitro
Activity of Cefotetan against ESBL-Producing Escherichia coli and Klebsiella pneumoniae Bloodstream Isolates from the MERINO Trial
Authors: Stewart Adam G. , Cottrell Kyra , Henderson Andrew , Vemuri Kanthi , Bauer Michelle J. , Paterson David L. , Harris Patrick N. A.
Published: July 2021

Carbapenem antibiotics remain the treatment of choice for severe infection due to ESBL- and AmpC-producing
Enterobacterales
. The use of carbapenems is a major driver of the emergence of carbapenem-resistant Gram-negative bacilli, which are often resistant to most available antimicrobials.
Limited Value of Single Sampling for IgM Antibody Determination as a Diagnostic Approach for Acute Hepatitis E Virus Infection
Authors: Rivero-Juarez Antonio , Lopez-Lopez Pedro , Pineda Juan Antonio , Alados Juan Carlos , Fuentes-López Ana , Ramirez-Arellano Encarnación , Freyre Carolina , Perez Ana Belén , Frias Mario , Rivero Antonio
Published: July 2021

In immunocompetent patients with a suspicion of hepatitis E virus (HEV) infection, single IgM antibody testing is typically applied. In this prospective study, we aimed to evaluate the accuracy of three different HEV screening approaches in patients with acute hepatitis, including approaches based on IgM determination, HEV RNA detection, and the combination of both.
Diagnostic Accuracy of Immunochromatographic Tests for the Detection of Norovirus in Stool Specimens: a Systematic Review and Meta-Analysis
Authors: Yoon Seo Hee , Kim Hye Rim , Ahn Jong Gyun
Published: July 2021

Noroviruses are the leading cause of acute gastroenteritis in all age groups and constitute a major health and economic burden worldwide. This systematic review and meta-analysis aimed to determine the diagnostic accuracy of immunochromatographic tests (ICTs) for the detection of norovirus in stool specimens, which has not been performed previously.
Severe diarrhoea due to use of P2Y12 inhibitor ticagrelor: a rarely reported adverse event
Authors: Rashid Khalid , Waheed Muhammad Aamir , Rehman Hafeez Ur , Elzouki Abdel-Naser
Published: July 2021

Ticagrelor is a part of dual antiplatelet therapy (DAPT) which has proven benefits in patients with acute coronary syndrome especially in those undergoing percutaneous coronary intervention (PCI). However, like most other drugs, it can lead to undesired and adverse effects such as dyspnoea, easy bruising and gastrointestinal bleeding. We present a case of 70-year-old woman who developed diarrhoea following initiation of DAPT comprising of aspirin and ticagrelor following PCI. After excluding more common causes, it was attributed to ticagrelor administration and completely resolved after it was replaced with another oral antiplatelet agent. On follow-up, the patient reported complete resolution of symptoms.
Late presentation of pulmonary artery pseudoaneurysm following bronchovascular sleeve resection of lung
Authors: Doyle Joseph , Mhandu Peter
Published: July 2021

A 43-year-old man with a history of double sleeve right upper lobectomy for pulmonary sarcoma, presented with worsening haemoptysis. Bronchoscopic and positron emission tomography (PET)CT appearances were suspicious for disease recurrence; however, on attending for CT-guided biopsy, he was found to have a large pseudoaneurysm of his right pulmonary artery. The patient underwent placement of endovascular covered stent with fluoroscopic confirmation of pseudoaneurysm occlusion, and was discharged home on lifelong antiplatelet therapy. To our knowledge, this is the first reported case of pulmonary artery pseudoaneurysm following double (bronchovascular) sleeve resection of the lung, successfully treated by endovascular stenting.
Study protocol: an open-label individually randomised controlled trial to assess the efficacy of artemether-lumefantrine prophylaxis for malaria among forest goers in Cambodia
Authors: Maude Richard James , Tripura Rupam , Ean Mom , Sokha Meas , Peto Thomas Julian , Callery James John , Imwong Mallika , Vongpromek Ranitha , Tarning Joel , Mukaka Mavuto , Waithira Naomi , Soviet Oung , von Seidlein Lorenz , Sovannaroth Siv
Published: July 2021

Introduction

In the Greater Mekong Subregion, adults are at highest risk for malaria. The most relevant disease vectors bite during daytime and outdoors which makes forest work a high-risk activity for malaria. The absence of effective vector control strategies and limited periods of exposure during forest visits suggest that chemoprophylaxis could be an appropriate strategy to protect forest goers against malaria.

Methods and analysis

The protocol describes an open-label randomised controlled trial of artemether-lumefantrine (AL) versus multivitamin as prophylaxis against malaria among forest goers aged 16–65 years in rural northeast Cambodia. The primary objective is to compare the efficacy of the artemisinin combination therapy AL versus a multivitamin preparation as defined by the 28-day PCR parasite positivity rate and incidence of confirmed clinical malaria of any species. The sample size is 2200 patient-episodes of duration 1 month in each arm. The duration of follow-up and prophylaxis for each participant is 1, 2 or 3 consecutive 28-day periods, followed by a further 28 days of post-exposure prophylaxis, depending on whether they continue to visit the forest. Analysis will be done both by intention to treat and per protocol.

Ethics and dissemination

All participants will provide written, informed consent. Ethical approval was obtained from the Oxford Tropical Research Ethics Committee and the Cambodia National Ethics Committee for Health Research. Results will be disseminated by peer-reviewed open access publication together with open data.

Trial registration number

NCT04041973; Pre-result.
Village-to-village screening for hepatitis B and C using quantitative HBsAg and anti-HCV testing with reflex HCV core antigen tests in the remote communities of a resource-rich setting: a population-based prospective cohort study
Authors: Chang Te-Sheng , Chang Kao-Chi , Chen Wei-Ming , Hsu Nien-Tzu , Lee Chih-Yi , Lin Yu-Chih , Huang Wei-Cheng , Chiu Wen-Nan , Hu Jin-Hung , Huang Tung-Jung , Chen Mei-Yen , Lu Sheng-Nan
Published: July 2021

Objectives

Community-based screening for hepatitis B virus (HBV) and hepatitis C virus (HCV) is essential for hepatitis elimination. This study attempted to increase screening accessibility and efficacy by using alternative tools.

Design

Population-based prospective cohort study.

Setting

Hepatitis elimination program at Yunlin County, Taiwan.

Participants

All 4552 individuals participated in 60 screening sessions of a community-based HBV and HCV screening project in five rural townships with approximately 95 000 inhabitants in central-western Taiwan.

Interventions

To increase accessibility, 60 outreach screening sessions were conducted in 41 disseminative sites. Quantitative HBV surface antigen (qHBsAg) and anti-HCV testing with reflex HCV core antigen (HCV Ag) tests were employed as alternative screening tools.

Main outcome measures

Calculate village-specific prevalence of HBsAg, anti-HCV and HCV Ag and establish patient allocation strategies according to levels of qHBsAg HCV Ag and alanine aminotransferase (ALT).

Results

Of 4552 participants, 553, 697 and 290 were positive for HBsAg, anti-HCV and HCV Ag, respectively; 75 of them had both HBsAg and anti-HCV positivity. The average (range) number of participants in each screening session was 98 (31–150). The prevalence rates (range) of HBsAg, anti-HCV and HCV Ag were 12.1% (4.3%–19.4%), 15.3% (2.6%–52.3%) and 6.4% (0%–30.2%), respectively. The HCV Ag positivity rate among anti-HCV-positive participants was 42% (0%–100%). Using cut-off values of >200 IU/mL for qHBsAg, >3 fmol/L for HCV Ag and >40 IU/mL for ALT as criteria for patient referral, we noted an 80.2% reduction in referral burden. Three villages had high anti-HCV prevalences of 52.3%, 53.8% and 63.4% with corresponding viraemic prevalences of 23.2%, 30.1% and 22% and thus constituted newly identified HCV-hyperendemic villages.

Conclusion

Outreach hepatitis screening increases accessibility for residents in rural communities. Screening HBV and HCV through qHBsAg and HCV Ag tests provides information concerning viral activities, which might be conducive to precise patient allocation in remote communities.
Safety of topical corticosteroids in atopic eczema: an umbrella review
Authors: Axon Emma , Chalmers Joanne R , Santer Miriam , Ridd Matthew J , Lawton Sandra , Langan Sinead M , Grindlay Douglas J C , Muller Ingrid , Roberts Amanda , Ahmed Amina , Williams Hywel C , Thomas Kim S
Published: July 2021

Objective

An umbrella review summarising all safety data from systematic reviews of topical corticosteroids (TCS) in adults and children with atopic eczema.

Methods

Embase, MEDLINE, PubMed, Cochrane Database of Systematic Reviews and the Centre of Evidence Based Dermatology map of eczema systematic reviews were searched until 7 November 2018 and Epistemonikos until 2 March 2021. Reviews were included if they assessed the safety of TCS in atopic eczema and searched>1 database using a reproducible search strategy. Review quality was assessed using version 2 of 'A MeaSurement Tool to Assess systematic Reviews' (AMSTAR 2 tool).

Results

38 systematic reviews included, 34 low/critically low quality. Treatment and follow-up were usually short (2–4 weeks).

Key findings

TCS versus emollient/vehicle: No meta-analyses identified for skin-thinning. Two 2-week randomised controlled trials (RCTs) found no significant increased risk with very potent TCS (0/196 TCS vs 0/33 vehicle in children and 6/109 TCS vs 2/50 vehicle, age unknown). Biochemical adrenal suppression (cortisol) was 3.8% (95% CI 2.4% to 5.8%) in a meta-analysis of 11 uncontrolled observational studies (any potency TCS, 522 children). Effects reversed when treatment ceased.

TCSversus topical calcineurin inhibitors: Meta-analysis showed higher relative risk of skin thinning with TCS (4.86, 95% CI 1.06 to 22.28, n=4128, four RCTs, including one 5-year RCT). Eight cases in 2068 participants, 7 using potent TCS. No evidence of growth suppression.

Once daily versus more frequent TCS: No meta-analyses identified. No skin-thinning in one RCT (3 weeks potent TCS, n=94) or biochemical adrenal suppression in two RCTs (up to 2 weeks very potent/moderate TCS, n=129).

TCS twice/week to prevent flares (‘weekend therapy’) versus vehicle: No meta-analyses identified. No evidence of skin thinning in five RCTs. One RCT found biochemical adrenal suppression (2/44 children, potent TCS).

Conclusions

Wefound no evidence of harm when TCS were used intermittently ‘as required’ to treat flares or ‘weekend therapy’ to prevent flares. However, long-term safety data were limited.

PROSPERO registration number

CRD42018079409.
Coached, Coordinated, Enhanced Neonatal Transition (CCENT): protocol for a multicentre pragmatic randomised controlled trial of transition-to-home support for parents of high-risk infants
Authors: Orkin Julia , Major Nathalie , Esser Kayla , Parmar Arpita , Couture Elise , Daboval Thierry , Kieran Emily , Ly Linh , O"Brien Karel , Patel Hema , Synnes Anne , Robson Kate , Barreira Lesley , Smith Wanda L , Rizakos Sara , Willan Andrew R , Yaskina Maryna , Moretti Myla E , Ungar Wendy J , Ballantyne Marilyn , Church Paige Terrien , Cohen Eyal
Published: July 2021

Introduction

Having an infant admitted to the neonatal intensive care unit (NICU) is associated with increased parental stress, anxiety and depression. Enhanced support for parents may decrease parental stress and improve subsequent parent and child outcomes. The Coached, Coordinated, Enhanced Neonatal Transition (CCENT) programme is a novel bundled intervention of psychosocial support delivered by a nurse navigator that includes Acceptance and Commitment Therapy-based coaching, care coordination and anticipatory education for parents of high-risk infants in the NICU through the first year at home. The primary objective is to evaluate the impact of the intervention on parent stress at 12 months.

Methods and analysis

This is a multicentre pragmatic randomised controlled superiority trial with 1:1 allocation to the CCENT model versus control (standard neonatal follow-up). Parents of high-risk infants (n=236) will be recruited from seven NICUs across three Canadian provinces. Intervention participants are assigned a nurse navigator who will provide the intervention for 12 months. Outcomes are measured at baseline, 6 weeks, 4, 12 and 18 months. The primary outcome measure is the total score of the Parenting Stress Index Fourth Edition Short Form at 12 months. Secondary outcomes include parental mental health, empowerment and health-related quality of life for calculation of quality-adjusted life years (QALYs). A cost-effectiveness analysis will examine the incremental cost of CCENT versus usual care per QALY gained. Qualitative interviews will explore parent and healthcare provider experiences with the intervention.

Ethics and dissemination

Research ethics approval was obtained from Clinical Trials Ontario, Children’s Hospital of Eastern Ontario Research Ethics Board (REB), The Hospital for Sick Children REB, UBC Children’s and Women’s REB and McGill University Health Centre REB. Results will be shared with Canadian level III NICUs, neonatal follow-up programmes and academic forums.

Trial registration number

ClinicalTrials.gov Registry (NCT03350243).
Factors associated with the decision to prescribe and administer antipsychotics for older people with delirium: a qualitative descriptive study
Authors: Tomlinson Emily J , Rawson Helen , Manias Elizabeth , Phillips Nicole (Nikki) M , Darzins Peteris , Hutchinson Alison M
Published: July 2021

Objectives

To explore factors associated with decision-making of nurses and doctors in prescribing and administering as required antipsychotic medications to older people with delirium.

Design

Qualitative descriptive.

Setting

Two acute care hospital organisations in Melbourne, Australia.

Participants

Nurses and doctors were invited to participate. Semi-structured focus groups and individual interviews were conducted between May 2019 and March 2020. Interviews were audio-recorded and transcribed verbatim. Data were analysed using thematic analysis.

Results

Participants were 42 health professionals; n=25 nurses and n=17 doctors. Themes relating to decisions to use antipsychotic medication were:safety; a last resort; nursing workload; a dilemma to medicate;andanticipating worsening behaviours. Nurses and doctors described experiencing pressures when trying to manage hyperactive behaviours. Safety was a major concern leading to the decision to use antipsychotics. Antipsychotics were often used as chemical restraints to ‘sedate’ a patient with delirium because nurses ‘can’t do their job’. Results also indicated that nurses had influence over doctors’ decisions despite nurses being unaware of this influence. Health professionals’ descriptions are illustrated in a decision-making flowchart that identifies how nurses and doctors navigated decisions regarding prescription and administration of antipsychotic medications.

Conclusions

The decision to prescribe and administer antipsychotic medications for people with delirium is complex as nurses and doctors must navigate multiple factors before making the decision. Collaborative support and multidisciplinary teamwork are required by both nurses and doctors to optimally care for people with delirium. Decision-making support for nurses and doctors may also help to navigate the multiple factors that influence the decision to prescribe antipsychotics.
Qualitative study on voyaging and health: perspectives and insights from the medical officers during the Worldwide Voyage
Authors: Mau Marjorie K Leimomi Mala , Minami Christina Mie , Stotz Sarah A , Albright Cheryl L , Kana'iaupuni Shawn Malia , Guth Heidi Kai
Published: July 2021

Objective

To examine the potential association of ocean voyaging with human health and well-being from the perspectives and experiences of the medical officers (MOs) who served during the Worldwide Voyage (WWV).

Design

Using a phenomenology framework, focus group and individual interviews were conducted and analysed by three diverse core researchers and then reviewed by three external researchers to enhance triangulation. Analysis used the Framework Method and Atlas-ti software (V.8.4.4) to facilitate coding, identify categories and develop an analytical matrix. The matrix was applied to all data using the constant comparative method to construct major themes and subthemes. Synthesised member checking was performed.

Setting

In 2014–2017, the WWV began in Hawai’i on a traditional voyaging canoe, known asHōkūle'a, using a non-instrument navigational method, ‘wayfinding’, powered only by natural forces and guided by traditional ecological knowledge. Each segment of the voyage included ~12 individuals, including an MO physician. The entire WWV included 172 ports-of-call, 36 legs and 250+ crew members.

Participants

We purposively sampled all MO physicians who participated in the WWV and enrolled 87% of eligible MOs (n=20 of 23). We conducted two focus groups (n=17=11+6, 85%) and three individual informant interviews (n=3, 15%).

Results

The four major themes: (1) Relationships; (2) Preventive Care to Enhance Health; (3) Holistic Health and Wellbeing beyond Voyaging and (4) Spiritual Transformative Experience, strongly suggest that ocean voyaging aboard a traditional voyaging canoe enhanced human health and well-being. The overall impact to perceived health and well-being extended beyond any increase in physical exercise. Essentially, traditional Polynesian ocean voyaging provided a cultural-based context for holistic health and well-being that influenced multiple levels and multiple dimensions.

Conclusion

Polynesian ocean voyaging was perceived as positively associated with holistic health and overall well-being and it may offer a new approach to confront complex health disparities.
Identification of anatomic risk factors for acute coronary events by optical coherence tomography in patients with myocardial infarction and residual nonflow limiting lesions: rationale and design of the PECTUS-obs study
Authors: Mol Jan-Quinten , Belkacemi Anouar , Volleberg Rick HJA , Meuwissen Martijn , Protopopov Alexey V , Laanmets Peep , Krestyaninov Oleg V , Dennert Robert , Oemrawsingh Rohit M , van Kuijk Jan-Peter , Arkenbout Karin , van der Heijden Dirk J , Rasoul Saman , Lipsic Erik , Teerenstra Steven , Camaro Cyril , Damman Peter , van Leeuwen Maarten AH , van Geuns Robert-Jan , van Royen Niels
Published: July 2021

Introduction

In patients with myocardial infarction, the decision to treat a nonculprit lesion is generally based on its physiological significance. However, deferral of revascularisation based on nonischaemic fractional flow reserve (FFR) values in these patients results in less favourable outcomes compared with patients with stable coronary artery disease, potentially caused by vulnerable nonculprit lesions. Intravascular optical coherence tomography (OCT) imaging allows for in vivo morphological assessment of plaque ‘vulnerability’ and might aid in the detection of FFR-negative lesions at high risk for recurrent events.

Methods and analysis

The PECTUS-obs study is an international multicentre prospective observational study that aims to relate OCT-derived vulnerable plaque characteristics of nonflow limiting, nonculprit lesions to clinical outcome in patients with myocardial infarction. A total of 438 patients presenting with myocardial infarction (ST-elevation myocardial infarction and non-ST-elevation myocardial infarction) will undergo OCT-imaging of any FFR-negative nonculprit lesion for detection of plaque vulnerability. The primary study endpoint is a composite of major adverse cardiovascular events (all-cause mortality, nonfatal myocardial infarction or unplanned revascularisation) at 2-year follow-up. Secondary endpoints will be the same composite at 1-year and 5-year follow-up, target vessel failure, target vessel revascularisation, target lesion failure and target lesion revascularisation.

Ethics and dissemination

This study has been approved by the Medical Ethics Committee of the region Arnhem-Nijmegen. The results of this study will be disseminated in a main paper and additional papers with subgroup analyses.

Trial registration number

NCT03857971.
TOPOLOGICAL PRESSURE OF POINCARÉ RECURRENCE SET
Authors: PEI YU , CHEN ERCAI , YAO KUI
Published: July 2021

This paper investigates the multifractal structure due to the recurrence under the [Formula: see text]th Bowen metric on the dynamical system. It is shown that the set with the given lower and upper recurrence rates can have the full topological pressure, if the system [Formula: see text] with specification property is non-minimal, and [Formula: see text] is positively expansive.
MULTIFRACTAL ANALYSIS OF COVID-19’S IMPACT ON CHINA’S STOCK MARKET
Authors: XU NAN , LI SONGSONG , HUI XIAOFENG
Published: July 2021

To examine the overall properties of the China’s stock market affected by the COVID-19 pandemic, we provide a comprehensive study of the multifractal properties across stock market sectors applying multifractal detrended fluctuation analysis (MF-DFA). We focus on intra-day 5[Formula: see text]min transaction data of 10 sectors in the Shanghai Stock Exchange, and the time-depended MF-DFA was also used to explore the dynamical evolution of the multifractal characterize for the overall period. We found that all sectors exhibit stronger multifractality and the weak market efficiency during the period of COVID-19, MHII performed best with the lower multifractal properties and higher market efficiency, three worse performers were ITII, TBII, and EII. While ITII, TBII, MCII, and UII were the four fastest recovering sectors from the gloom of the epidemic, with the plummeted multifractal intensity and the significantly increased market efficiency for the post-phase of the pandemic. The results based on the time-varying MF-DFA confirmed that the Chinese stock market is not only affected by the COVID-19 epidemic domestic but the impact of the US stock market crash in March was also transmitted to it, causing those industries sensitive to the market to fluctuate subsequently.
Relative global Gorenstein dimensions
Authors: Becerril Víctor
Published: July 2021

Let [Formula: see text] be an abelian category. In this paper, we investigate the global [Formula: see text]-Gorenstein projective dimension [Formula: see text], associated to a GP-admissible pair [Formula: see text]. We give homological conditions over [Formula: see text] that characterize it. Moreover, given a GI-admissible pair [Formula: see text], we study conditions under which [Formula: see text] and [Formula: see text] are the same.
A note on prime number races and zero free regions for L functions
Authors: Aymone Marco
Published: July 2021

Let [Formula: see text] be a real and non-principal Dirichlet character, [Formula: see text] its Dirichlet [Formula: see text]-function and let [Formula: see text] be a generic prime number. We prove the following result: If for some [Formula: see text] the partial sums [Formula: see text] change sign only for a finite number of integers [Formula: see text], then there exists [Formula: see text] such that [Formula: see text] has no zeros in the half plane [Formula: see text].
A note on arithmetic behavior of Hecke eigenvalues of Siegel cusp forms of degree two
Authors: Chen Guohua , Li Weiping
Published: July 2021

Let [Formula: see text] and [Formula: see text] be Siegel cusp forms for the group [Formula: see text] with weights [Formula: see text], [Formula: see text], respectively. Suppose that neither [Formula: see text] nor [Formula: see text] is a Saito–Kurokawa lift. Further suppose that [Formula: see text] and [Formula: see text] are Hecke eigenforms lying in distinct eigenspaces. In this paper, we investigate simultaneous arithmetic behavior and related problems of Hecke eigenvalues of these Hecke eigenforms, some of which improve upon results of Gun et al.
Syntactic Coherence in Word Embedding Spaces
Authors: Ravindran Renjith P. , Murthy Kavi Narayana
Published: July 2021

Word embeddings have recently become a vital part of many Natural Language Processing (NLP) systems. Word embeddings are a suite of techniques that represent words in a language as vectors in an n-dimensional real space that has been shown to encode a significant amount of syntactic and semantic information. When used in NLP systems, these representations have resulted in improved performance across a wide range of NLP tasks. However, it is not clear how syntactic properties interact with the more widely studied semantic properties of words. Or what the main factors in the modeling formulation are that encourages embedding spaces to pick up more of syntactic behavior as opposed to semantic behavior of words. We investigate several aspects of word embedding spaces and modeling assumptions that maximize syntactic coherence — the degree to which words with similar syntactic properties form distinct neighborhoods in the embedding space. We do so in order to understand which of the existing models maximize syntactic coherence making it a more reliable source for extracting syntactic category (POS) information. Our analysis shows that syntactic coherence of S-CODE is superior to the other more popular and more recent embedding techniques such as Word2vec, fastText, GloVe and LexVec, when measured under compatible parameter settings. Our investigation also gives deeper insights into the geometry of the embedding space with respect to syntactic coherence, and how this is influenced by context size, frequency of words, and dimensionality of the embedding space.
Internal Conversion in the Membrane-Supported SOFC
Authors: Samoilov Aleksandr , Agarkov Dmitrii Aleksandrovich , Fedotov Yuri , Bredikhin Sergey Ivanovich
Published: July 2021

Studies of the internal methane conversion process were carried out on an experimental short stack of two 100x100 mm electrolyte-supported SOFCs. A whole series of experiments were carried out on H2+CH4+H2O mixtures with different sets of conditions – an increase in the ratio and consumption of methane, and then a decrease in temperature. The results of experiments at an operating temperature of 850°C showed that the kinetics of internal conversion was largely underestimated. The assembly of two SOFCs converts methane up to concentrations not exceeding the calculated equilibrium ones, up to the maximum available flow rate on the equipment used – 187 ml/min – even without current passing. This fuel flow rate can provide a current of up to 53 A, while the rated operating current of these SOFCs is about 20 A, up to 30 A on methane-rich fuel. The current further stimulates the conversion by generating additional steam.
Progress of SOC Development at Elcogen
Authors: Noponen Matti , Torri Pauli , Göös Jukka , Puranen Jouni , Lehtinen Timo , Pylypko Sergii , Ounpuu Enn
Published: July 2021

Elcogen is a company providing solid oxide cell and stack solutions for fuel cell (SOFC) and electrolysis (SOEC) applications. Elcogen’s solutions are designed to operate at reduced operating temperatures but still providing high performance at affordable cost and low degradation level. Elcogen is currently expanding its manufacturing capabilities towards multi-MW annual production levels through a factory project. As a part of commercialization tasks, Elcogen is developing a demonstrator unit for steam electrolysis applications producing green hydrogen. This demonstrator unit is a part of an EU’s H2020 funded C2FUEL project. This presentation outlines the current progress of the high temperature electrolysis demonstrator development at Elcogen.
Development of an Efficient rSOC Based Renewable Energy Storage System
Authors: Mouginn Julie , Cubizolles Geraud , Hauch Anne , Pennanen Jari , Alvarez Joaquin , Pylypko Sergii , Potron Marc , Marquillier Bastien , Hody Stephane , Cesareo Gianna , Fiorot Sabina , Perez Guillermo
Published: July 2021

While renewable energies locally installed in buildings are increasing, there is a potential or even a need to store them to promote their self-consumption. Being efficient, modular, and scalable, reversible Solid Oxide Cell (rSOC) technology can play a key role. Works undertaken in the frame of the REFLEX European project are presented, starting with the optimization of each individual component, ie. cells, stacks, and BoP components such as power electronics. With the support of modelling activities, the rSOC based system, made of 3 modules of 4 stacks each, coupled with a battery storage, has been designed in such a way to ensure achieving maximum efficiency, while still operating the system in safe and lifetime-optimal conditions. The site where the system will be installed has been prepared. Furthermore, techno-economic simulations have been carried out to evaluate market driven requirements on system sizing and costs to be competitive with other storage solutions.
1MW-Class Solid Oxide Electrolyser System Prototype for Low-Cost Green Hydrogen
Authors: Harman Jonathan , Hjalmarsson Per , Mermelstein Joshua , Ryley Joshua , Sadler Harry , Selby Mark
Published: July 2021

Ceres aims to play a central role in the global transition to clean, affordable energy to help tackle climate change and air pollution. As part of this goal, Ceres is now focused on applying its well-established and mature solid oxide cell technology to electrolysis system applications as a compelling solution that can address the carbon emissions from the so called hard-to-abate sectors in heavy industry (cement, steel, and chemicals) and heavy-duty transport (road haulage, shipping, and aviation). These sectors represent 10GtCO2 or 30% of CO2 emissions from energy and industry(1). This paper describes Ceres proposed development path from a first-of-a-kind prototype system demonstrator towards full technology maturation and commercialization over the next 5 years. The advantages of heat integration with Ceres’ solid oxide electrolyzer (SOEL) system are explored and a roadmap to the first commercial SOEL systems is presented setting out predicted system capital expenditure and hydrogen production costs.
Understanding High-Temperature Electrolysis
Authors: Foit Severin , Dittrich Lucy , Nohl Markus , Vinke I. C. , Eichel Rüdiger-A. , De Haart L. G. J. (Bert)
Published: July 2021

Electrolysis is the technology, which provides the key for sector coupling. It enables the conversion of renewable energy to material value generation. Obviously, it is of utmost importance, that the energy is used in the most efficient way. High-temperature electrolysis on solid oxide cells provides high efficiency combined with the possibility to convert both water (H2O) and carbon dioxide (CO2) to hydrogen (H2) and carbon monoxide (CO) at the same time. In this contribution, we show the summary and conclusions of multiple investigations of the high-temperature electrolysis. A series of detailed analysis has been performed using current-voltage characteristics (IV curves), electrochemical impedance spectroscopy (EIS), and theoretical calculations.
Model-Based Optimization of Solid Oxide Electrolysis Cells and Stacks for Power-to-Gas Applications
Authors: Wehrle Lukas , Schmider Daniel , Dailly Julian , Banerjee Aayan , Deutschmann Olaf
Published: July 2021

Power-to-Methane (PtM) is an attractive chemical storage concept enabling the coupling of intermittent renewable energy sources with the gas grid. Here, we use a combined experimental and modeling methodology to investigate and optimize solid oxide electrolysis cells (SOECs) and stacks operation for PtG applications. Firstly, electrode- and electrolyte-supported single cells from commercial suppliers are characterized in terms of their electrochemical performance and their microstructure. By implementing the structural data into a detailed single cell model and by reproducing steady-state polarization curves, the model is calibrated and validated for both cell designs. Subsequently, 2D adiabatic simulations are conducted to examine the performance of both cell types in detail. Afterwards, a scale-up to the 3D stack level is performed to correlate the model-predicted stack performance with that of a single repeating unit, which illustrates the implications of scaling-up on the SOEC performance. These analyses can provide valuable guidelines for cell and stack design considerations for PtM applications.
Modeling of Reversible Solid Oxide Cell Stacks with an Open-Source Library
Authors: Zhang Shidong , Peters Roland , Varghese Bob Austin , Deja Robert , Kruse Nicolas , Beale Steven B. , Blum Ludger , Peters Ralf
Published: July 2021

This study describes a homogenized model of reversible solid oxide cell (rSOC) stacks. The model enables steady-state simulations of rSOC stacks in both fuel cell and electrolyzer modes to be conducted. It accounts for multi-component species diffusion, and heat and mass transfer, including thermal radiation and electrochemical reactions. An open-source library, OpenFOAM, provides a platform for the model’s implementation. Numerical simulations were performed using an in-house-designed rSOC stack. A previously-developed, one-dimensional Simulink model was also applied to the stack. Both models predict similar output voltages, within 2% difference, under the same operating conditions. Temperature variations were also compared; the stack model’s results were closer to experimental measurements than the Simulink model. The new model was able to perform faster simulations (less than 2 hours) for the prescribed stacks.
Solid Oxide Cell Technology Development at TNO
Authors: Berkel Frans , Ferchaud Claire Julie , Partenie Octavian , Linders Marco , van Delft Yvonne
Published: July 2021

An overview of the most recent status of Solid Oxide Cell (SOC) and stack developments within TNO will be presented. The techno-economic analysis of methanol synthesis using co-electrolysis of CO2 and H2O as the source of the required syngas for methanol synthesis demonstrates the feasibility of the methanol synthesis at a production cost of < 700 €/ton. The in-house solid oxide cell manufacturing development has resulted in high porosity fuel electrode-supported-cells with cell dimensions up to 20x20 cm2, capable of high performance steam-, co- and CO2 electrolysis. Both an experimental proof of co-electrolysis of CO2 and steam towards a syngas composition suited for methanol synthesis and CO2-electrolysis have been realized on a single cell level, making use of 10x10 cm2 electrode-supported cells. CO2-electrolysis towards CO, demonstrated CO2-conversion levels up to 60%.
Commercialization of the Ceres Power SteelCell® Technology: Latest Update
Authors: Leah Robert , Bone Adam , Selcuk Ahmet , Lankin Mike , Rahman Mahfujur , Clare Andy , Reade Gavin , Felix Florence , De Vero Jeffrey , Wang XIn , Mukerjee Subhasish , Selby Mark
Published: July 2021

Ceres’ unique SteelCell® metal supported SOC technology is increasingly establishing itself as the global standard for SOC, combining robustness, efficiency, and low manufacturing cost. The technology is rapidly moving from demonstration to true volume production, with Robert Bosch GmbH in Germany and Doosan Fuel Cell in South Korea both having licenses to manufacture SteelCell cells and stacks at the hundreds of MW per year scale aiming for full scale production by 2024. Bosch and Ceres currently have manufacturing plants making MW of stacks per year. SteelCell technology has a wide range of applications in the power generation sector, with applications ranging from small scale <10kWe combined heat and power (CHP) systems to systems in the 100s of kW to MW range. There are also applications in the transport sector for heavy duty electric vehicle range extenders and potentially marine propulsion systems. The technology also has applications in the rapidly-growing steam electrolysis and E-fuels sector.
Development of Metal-Supported Proton-Conducting Solid Oxide Cells Via Co-Sintering
Authors: Lau Grace Y. , Tucker Mike C
Published: July 2021

Metal-supported solid oxide cells with P434L stainless steel support and BZCYYb-4411 electrode backbone and electrolyte layers are fabricated. Sintering aids for the ceramic layer are optimized. LiF is found to lower the ceramic sintering temperature too much. Manganese oxide enhances sintering and densification without dramatically reducing the sintering onset temperature. The impact of metal particle size on sintering is assessed. A symmetric structure helps to prevent warping or cracking arising from residual mis-match between the metal and ceramic sintering shrinkage. Intact cell structures are successfully prepared with <15 μm stainless steel particles and 2 wt% manganese oxide added to the BZCYYb-4411 layers.
Metal Supported Proton Conducting Ceramic Cell with Thin Film Electrolyte for Electrolysis Application
Authors: Zheng Haoyu , Han Feng , Sata Noriko , Riegraf Matthias , Dayaghi Amir Masoud , Norby Truls , Costa Rémi
Published: July 2021

Manufacturing of metal supported proton conducting ceramic cells is investigated in the present study. A low temperature fabrication route was chosen to avoid metal corrosion during the fabrication process, in which pulsed laser deposition (PLD) was employed to apply the thin-film BaZr0.7Ce0.2Y0.1O3-δ electrolyte layer. The surface condition of the support layer is a critical aspect to produce a dense and gas-tight electrolyte layer by PLD. In order to decrease the average size of the 10-30 µm large pores in metal substrate down to the nano-scale, different powders with different particles size were successfully fabricated and integrated into a pore-size graded structure to form a homogeneous porous surface whose size distribution meets the requirements for making a dense PLD coating layer. An electrolyte layer with the intended phase is achieved with a thickness of around 1 µm. Initial electrochemical investigation with a Pt oxygen electrode showed a total resistance of 4.92 Ω cm2 at 600°C at OCV.
Numerical Analysis of the Local Current Efficiency Distribution in a Protonic Ceramic Fuel Cell Considering Gas Concentration Distributions
Authors: Li Kunpeng , Suito Fumiyasu , Ryogo Takatera , Atsuhito Ota , Araki Takuto , Okuyama Yuji , Mori Masashi
Published: July 2021

Intermediate-temperature protonic ceramic fuel cells (PCFCs) are expected to be highly efficient energy conversion devices because of their high proton conductivity in the electrolyte. However, besides the main proton conductivity, some other charge carriers, such as electron holes, are also conductive in PCFCs, leading to a decrease in current efficiency. The conductivities are not only affected by the operating temperature but are also strongly influenced by the gas concentrations, which causes complexities in PCFC performance. To reveal the performance and provide feedback to the operating condition selections considering the reaction overpotential, a quasi-two-dimensional Nernst-Planck-Poisson (NPP) numerical model was successfully used to investigate the current efficiency distribution in a planar-type PCFC electrolyte with BaZr0.8Yb0.2O3-δ (BZYb20). The influence of the gas flow direction was also revealed in the present study. The results showed almost the same average current efficiency with co- and counter-flows but flat proton distributions with counter-flows.
Numerical Simulation of an Internal Reforming Solid Oxide Fuel Cell Unit Fueled with Hydrogen-Natural Gas Mixtures
Authors: Fan Junhua , Wang Yuqing , Shi Jixin , Shi Yixiang , Cao Haishan , Cai Ningsheng
Published: July 2021

Blending hydrogen into natural gas grid can effectively reduce carbon emissions and promote the development of the hydrogen economy. Utilizing hydrogen-natural gas mixtures through internal reforming solid oxide fuel cells (SOFCs) can convert the chemical energy of the fuels direct into electricity, which is a promising technology for combined heat and power systems. In this study, a three-dimensional model for an internal reforming solid oxide fuel cell unit is developed coupling chemical and electrochemical reactions, mass, momentum, and heat transfer processes. The influences of the hydrogen addition on the distributions of temperature, gas compositions, and current density are studied by changing the hydrogen blending ratios in inlet gas mixtures. The simulation results show that the addition of hydrogen affects the coupling of the endothermic reforming reactions and exothermic electrochemical reactions, which leads to improved temperature uniformity and higher current density of the SOFC unit compared with pure methane feeding.
A Dynamic Multi-Scale Model for Solid Oxide Cells Validated on Local Current Measurements: Impact of Global Cell Operation on the Electrodes Reaction Mechanisms
Authors: Da Rosa Silva Eduardo , Hubert Maxime , Morel Bertrand , Moussaoui Hamza , Debayle Johan , Laurencin Jérôme
Published: July 2021

A dynamic physically based model has been developed to unravel the relationships between the overall Solid Oxide Cells response and the reaction mechanisms taking place in the electrodes. This tool combines modules at three different length-scales: electrode microstructures, active functional layers, and single repeat unit. It allows computing the cell polarization together with the distribution of the local current densities, overpotentials, and gas composition. It has been shown that the synthetic electrode model reproduces accurately the real microstructure, which has been checked by comparison with 3D reconstructions. The microscale electrode models have been validated using polarization curves and impedance spectra measured in symmetrical cells. Finally, tests were conducted at different temperatures and inlet flow rates to validate the integrated multiscale approach. For this purpose, a special setup was developed to measure the local current densities in standard cells. A good agreement was found between the experimental and simulated data.
Optimization of SOFC Electrode Microstructures with Long Term Performance Modeling and Machine Learning
Authors: Epting William K , Lei Yinkai , Mason Jerry H , Abernathy Harry W. , Kalapos Thomas , Hackett Gregory A
Published: July 2021

To understand the relationship between SOFC electrode microstructure and long-term performance, we developed a fully resolved 4D model for simulating microstructural and performance changes over 1,000 hours of cell operation by combining a phase-field coarsening model with spatially resolved microstructural analysis and continuum-level multiphysics performance modeling. This framework was used to simulate the long-term performance of hundreds of LSM-YSZ cathodes and Ni-YSZ anodes. These electrode microstructures were synthetically generated to intentionally span an 11-dimensional space of initial microstructural parameters. These high-dimensional results were analyzed with a machine learning model using a novel figure of merit that accounts for both the initial and long-term performance. This demonstrated that e.g. the LSM/YSZ ratio was the most impactful parameter in the cathode microstructure, with lower LSM/YSZ ratios generally being beneficial. The trained model also produces tailored recommendations for improvements to existing electrodes, providing a valuable tool for SOFC electrode developers and manufacturers.
An Optimized Strategy for Fuel Cell Degradation Control in SOFC Power Systems
Authors: Zhu Jianzhong , Wu Xintao , Sun Kaihua , Han Minfang
Published: July 2021

Solid Oxide Fuel Cell (SOFC) is an attractive energy conversion device due to its high efficiency and fuel flexibility. Key operation parameters such as current, temperature, and fuel utilization are critical variables in SOFC systems that directly impact efficiency and longevity. The degradation of the SOFC performance not only limits the operating temperature range of the SOFC stack in the system, but also simultaneously generates Joule heat, which further causes the stack to deviate from its initial thermal balance.In this paper, a semi-empirical SOFC dynamic model with degradation is proposed and validated by experiment data. The degradation in the above model is developed based on current density, temperature, and fuel utilization to simulate cell performance decay over time due to ohmic loss growth and the heat generation by cell resistance. The coupling between key parameters, stack performance, and degradation during long-term load following and the impact of stack degradation on the entire system long-term performance is discussed and investigated. An optimized strategy uses both feedback and feed-forward control law is designed to track the desired power demand with the aim of mitigating the degradation and compensating the time differences between dynamics at different time-scale.
Post-Operational Characterization of a Long-Term Operated Solid Oxide Fuel Cell Stack
Authors: Menzler Norbert , Sebold Doris , Zischke Sebastian , Zurek Joanna , Naumenko Dmitry , Gross-Barsnick Sonja
Published: July 2021

A two-layer solid oxide cell stack based on anode-supported cells was operated galvanostatically at 0.5 A / cm² and 700°C for nearly 100,000 h in fuel cell mode. After stack dissection and post-test analysis, it was ascertained that most of the components were visually in good condition despite 11 years of operation. This presentation summarizes the post mortem findings covering the cell, the metal parts of the stack, and the glass-ceramic sealant.