bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of progenitor cell lineage rerouting in the adult mouse hippocampus
Authors: Moura Daniela M.S. , Brandão Juliana Alves , Lentini Celia , Heinrich Christophe , Queiroz Claudio M. , Costa Marcos R.
Published: June 2020

Cell lineage in the adult hippocampus comprises multipotent and neuron-committed progenitors. In the present work, we fate-mapped neuronal progenitors using Dcx-CreERT2 and CAG-CAT-EGFP double-transgenic mice (cDCX/EGFP). We show that three days after tamoxifen-mediated recombination in cDCX/EGFP adult mice, GFP+ cells in the dentate gyrus co-expresses DCX and about 6% of these cells are proliferative neuronal progenitors. After 30 days, 20% of GFP+ generated from these progenitors differentiate into GFAP+ astrocytes. Administration of the chemoconvulsants kainic acid (KA) or pilocarpine (PL) led to a significant increase in the number of GFP+ cells in both ipsi and contralateral dentate gyrus. However, while PL favored the differentiation of neurons in both ipsi- and contralateral sides, KA stimulated neurogenesis only in the contralateral side. In the ipsilateral side, KA injection led to an unexpected increase of astrogliogenesis in the Dcx-lineage. These different effects of KA and PL in the Dcx-lineage are associated with distinct alterations of the parvalbuminergic plexus and inflammatory responses in the hippocampi. Finally, we also observed a small number of GFP+/GFAP+ cells displaying radial-glia morphology ipsilaterally 3 days after KA administration, indicating that Dcx-progenitors could regress to a multipotent stage. Altogether, our data suggest that cell lineage in the adult hippocampus is not unidirectional and can be modulated by environmental signals.
Zinc protection of fertilized eggs is an ancient feature of sexual reproduction in animals
Authors: Wozniak Katherine L. , Bainbridge Rachel E. , Summerville Dominique W. , Tembo Maiwase , Phelps Wesley A. , Sauer Monica L. , Wisner Bennett W. , Czekalski Madelyn E. , Pasumarthy Srikavya , Hanson Meghan L. , Linderman Melania B. , Luu Catherine H. , Boehm Madison E. , Sanders Steven M. , Buckley Katherine M. , Bain Daniel J. , Nicotra Matthew L. , Lee Miler T. , Carlson Anne E.
Published: June 2020

One of the earliest and most prevalent barriers to successful reproduction is polyspermy, or fertilization of an egg by multiple sperm. To prevent these supernumerary fertilizations, eggs have evolved multiple mechanisms. It has recently been proposed that zinc released by mammalian eggs at fertilization may block additional sperm from entering. Here, we demonstrate that eggs from amphibia and teleost fish also release zinc. UsingXenopus laevisas a model, we document that zinc reversibly blocks fertilization. Finally, we demonstrate that extracellular zinc similarly disrupts early embryonic development in eggs from diverse phyla, including: Cnidaria, Echinodermata, and Chordata. Our study reveals that a fundamental strategy protecting human eggs from fertilization by multiple sperm may have evolved more than 650 million years ago.
Increased demand for NAD+ relative to ATP drives aerobic glycolysis
Authors: Luengo Alba , Li Zhaoqi , Gui Dan Y. , Sullivan Lucas B. , Zagorulya Maria , Do Brian T. , Ferreira Raphael , Naamati Adi , Ali Ahmed , Lewis Caroline A. , Thomas Craig J. , Spranger Stefani , Matheson Nicholas J. , Vander Heiden Matthew G.
Published: June 2020

Aerobic glycolysis, or preferential fermentation of glucose-derived pyruvate to lactate despite available oxygen, is a hallmark of proliferative metabolism that is observed across many organisms and conditions. To better understand why aerobic glycolysis is associated with cell proliferation, we examined the metabolic consequence of activating the pyruvate dehydrogenase complex (PDH) to increase mitochondrial pyruvate oxidation at the expense of fermentation. We find that increasing PDH activity impairs cell proliferation by reducing the nicotinamide adenine dinucleotide cofactor ratio (NAD+/NADH). This change in NAD+/NADH ratio is caused by an increase in mitochondrial membrane potential that impairs mitochondrial electron transport and NAD+ regeneration. Uncoupling mitochondrial respiration from ATP synthesis or increasing ATP hydrolysis restores NAD+/NADH homeostasis and proliferation even when glucose oxidation is increased. These data suggest that when the demand for NAD+ to support oxidation reactions exceeds the demand for ATP consumption in cells, NAD+ regeneration by mitochondrial respiration becomes constrained, promoting fermentation despite available oxygen. This argues that cells engage in aerobic glycolysis when the cellular demand for NAD+ is in excess of the cellular demand for ATP.
Dietary sphinganine is selectively assimilated by members of the gut microbiome
Authors: Lee Min-Ting , Le Henry H. , Johnson Elizabeth L.
Published: June 2020

Functions of the gut microbiome have a growing number of implications for host metabolic health, with diet being one of the most significant influences on microbiome composition. Compelling links between diet and the gut microbiome suggest key roles for various macronutrients, including lipids, yet how individual classes of dietary lipids interact with the microbiome remain largely unknown. A class of lipids known as sphingolipids are bioactive components of most foods and are produced by prominent gut microbes. This makes sphingolipids intriguing candidates for shaping diet-microbiome interactions. Here, we use a click-chemistry based approach to track the incorporation of bioorthogonal dietary omega-alkynyl sphinganine (sphinganine alkyne – SAA) into the gut microbial community (Click). Identification of microbe and SAA-specific metabolic products was achieved by fluorescence-based sorting of SAA containing microbes (Sort), 16S rRNA gene sequencing to identify the sphingolipid-interacting microbes (Seq), and comparative metabolomics to identify products of SAA assimilation by the microbiome (Spec). Together this approach, Click-Sort-Seq-Spec (ClickSSS), revealed that SAA-assimilation was nearly exclusively performed by gutBacteroides, indicating that sphingolipid-producing bacteria play a major role in processing dietary sphinganine. Comparative metabolomics of cecal microbiota from SAA-treated mice showed conversion of SAA to a suite of dihydroceramides, consistent with metabolic activity viaBacteroidesandBifidobacterium. Additionally, other sphingolipid-interacting microbes were identified with a focus on an uncharacterized ability ofBacteroidesandBifidobacteriumto metabolize dietary sphingolipids. Therefore, ClickSSS provides a platform to study the flux of virtually any alkyne-labeled metabolite in diet-microbiome interactions.
Monet: An open-source Python package for analyzing and integrating scRNA-Seq data using PCA-based latent spaces
Authors: Wagner Florian
Published: June 2020

Single-cell RNA-Seq is a powerful technology that enables the transcriptomic profiling of the different cell populations that make up complex tissues. However, the noisy and high-dimensional nature of the generated data poses significant challenges for its analysis and integration. Here, I describeMonet, an open-source Python package designed to provide effective and computationally efficient solutions to some of the most common challenges encountered in scRNA-Seq data analysis, and to serve as a toolkit for scRNA-Seq method development. At its core, Monet implements algorithms to infer the dimensionality and construct a PCA-based latent space from a given dataset. This latent space, represented by aMonetModelobject, then forms the basis for data analysis and integration. In addition to validating these core algorithms, I provide demonstrations of some more advanced analysis tasks currently supported, such as batch correction and label transfer, which are useful for analyzing multiple datasets from the same tissue. Monet is available athttps://github.com/flo-compbio/monet. Ongoing work is focused on providing electronic notebooks with tutorials for individual analysis tasks, and on developing interoperability with other Python scRNA-Seq software. The author welcomes suggestions for future improvements.
Aging interacts with tumor biology to produce major changes in the immune tumor microenvironment
Authors: Erbe Rossin , Wang Zheyu , Zaidi Neeha , Topper Michael , Baylin Stephen , Jaffee Elizabeth M , Easwaran Hariharan , Fertig Elana J
Published: June 2020

Advanced age is strongly correlated with both increased cancer incidence and general immune decline. The immune tumor microenvironment (ITME) has been established as an important prognostic of both therapeutic efficacy and overall patient survival. Thus, age-related immune decline is an important consideration for the treatment of a large subset of cancer patients. Current studies of aging-related immune alterations are predominantly performed on non-cancerous tissue, requiring additional study into the effects of age on tumor immune infiltration. We leverage large scale transcriptional data sets from The Cancer Genome Atlas and the Genotype-Tissue Expression project to distinguish normal age-related immune alterations from age-related changes in tumor immune infiltration. We demonstrate that while there is overlap between the normal immune aging phenotype and that of the ITME, there are several changes in immune cell abundance that are specific to the ITME, particularly in T cell, NK cell, and Macrophage populations. These results suggest that aged immune cells are more susceptible to tumor suppression of cytotoxic immune cell infiltration and activity than normal tissues, which creates an unfavorable ITME in older patients in excess of normal immune decline with age and may inform the application of existing and emerging immunotherapies for this large population of patients. We additionally identify that age-related increases in tumor mutational burden are associated with decreased DNA methylation and increased expression of the immune checkpoint genesPDL1, CD80,andLAG3which may have implications for therapeutic application of immune checkpoint blockade in older patients.
Caffeine decreases neuromuscular fatigue in the lumbar muscles – a randomized blind study
Authors: Cardoso Liziane , Nery Tatyana , Gonçalves Maielen , Carolina Speck Maria , de Bem Alves Ana Cristina , Bristot Viviane , Gonçalves Thais , Scheffer Débora da Luz , Schneider Ione Jayce Ceola , Kuriki Heloyse , S Aguiar Aderbal
Published: June 2020

Background

Ergogenic evidence for caffeine is robust in sports and isolated limb tasks. Our objective was to evaluate a possible ergogenic effect on postural muscles, still unknown, through the Biering-Sørensen’s lumbar extension test.

Methods

A double-blind, controlled placebo, crossover study. Fifty-one healthy, physically inactive male subjects (18-25 years) with average body mass (BMI 18.5 – 24.9 kg/m2) were recruited. The subjects received oral caffeine (6 mg/kg) and saline (0.3%) in two cross-evaluations separated by one week. The primary outcome was the time in the Biering-Sørensen test after 1 hour of treatment. The secondary outcomes were peak lumbar extension force, rating of perceived exertion, EMG’s median frequency and muscle recruitment of multifidus spinae and transversalis/interne oblique muscles, and cardiovascular variables (heart rate and blood pressure).

Results

27 subjects were blindly treated with caffeine and saline. Caffeine was ergogenic during the Biering-Sørensen test. It increased lumbar extension time (d = 0.34, P<0.05), but not peak force. The perception of effort decreased with caffeine (d = 0.37, P<0.05). Caffeine increased muscle stimulation frequency (P<0.05) and recruitment (η2 = 0.49, P<0.05) of multifidus spinae. In the transversalis/interne oblique muscles, caffeine increased the median frequency η2 = 0.13, P<0.05) and the distribution of higher frequencies (P<0.05). Caffeine also increased muscle recruitment in the transversalis/interne oblique muscles η2 = 0.13, P<0.05) Tachycardia and increased blood pressure at the lumbar test were higher in the caffeine condition (P< 0.05).

Conclusions

Our results show that caffeine is ergogenic for postural muscles. Decreased RPE and improved muscle activity suggest central mechanisms of caffeine.

Trial registration

UTN U1111-1234-2079.

BULLET POINTS

Caffeine increases the extension time of the lumbar spine in the Biering-Sørensen test.

Caffeine decreases perceived exertion during the Biering-Sørensen test.

Caffeine increases muscle stimulation and recruitment of the multifidus spinae during the Biering-Sørensen test.

Caffeine increases muscle stimulation of the transversalis/interne oblique muscles during the Biering-Sørensen test.
Development and validation of a potential salivary biomarker panel for Oral Squamous Cell Carcinoma
Authors: Jain Anu , Kotimoole Chinmaya Narayana , Ghoshal Sushmita , Bakshi Jaimanti , Chatterjee Aditi , Keshav Prasad Thottethodi Subrahmanya , Pal Arnab
Published: June 2020

Purpose

Oral Squamous Cell Carcinoma (OSCC) is one of the most prevalent cancers in the world with maximum number of cases reported from India. Poor survival rate associated with OSCC can be attributed to non-availability of a biomarker, as one of the major reasons, leading to late presentation. Identification of an early diagnostic biomarker, which can also be used as a screening tool, will be helpful in reducing the disease morbidity and mortality.

Experimental Design

In this article we report Parallel Reaction Monitoring (PRM) based validation of 12 candidate proteins, identified initially by TMT tag based relative quantification of salivary proteins on LC-MS, in the saliva of Oral Squamous Cell Carcinoma (OSCC) cases (N=50) and healthy controls (N=49), AZGP1, AHSG, KRT6C, S100A7, S100A9, KLK1, BPIFB2, IGLL5, CORO1A, LACRT, LCN2 and PSAP. Heavy isotope labelled reference peptides were used to produce calibration curve and absolute quantification of proteins and resulting data was analyzed statistically using R.

Results

Salivary AHSG (p=0.0041**) and KRT6C (p=0.002**) were significantly upregulated in OSCC cases while AZGP1 (p=<0.0001***), KLK1 (p=0.006**) and BPIFB2 (p=0.0061**) were significantly downregulated. Multivariate logistic regression modelling resulted in a risk prediction model consisting of AZGP1, AHSG and KRT6C with p value <0.0001***. Using this model ROC with area under the curve of 82.2% was produced and sensitivity and specificity observed for this model was 78% and 73.5%. Positive and negative predictive values for the model were 76% and 75% respectively.

Conclusion

We report a potential biomarker panel consisting of proteins AZGP1, AHSG and KRT6C for early diagnosis of OSCC.
Principles and Practice of SARS-CoV-2 Decontamination of N95 Masks with UV-C
Authors: Huber Thomas , Goldman Olivia , Epstein Alexander E. , Stella Gianna , Sakmar Thomas P.
Published: June 2020

A mainstay of personal protective equipment (PPE) during the COVID-19 pandemic is the N95 filtering facepiece respirator. N95 respirators are commonly used to protect healthcare workers from respiratory pathogens, including the novel coronavirus SARS-CoV-2, and are increasingly employed by other frontline workers and the general public. Under routine circumstances, these masks are disposable, single-use items, but extended use and reuse practices have been broadly enacted to alleviate critical supply shortages during the COVID-19 pandemic. While extended-time single use presents a low risk of pathogen transfer, repeated donning and doffing of potentially contaminated masks presents increased risk of pathogen transfer. Therefore, efficient and safe decontamination methods for N95 masks are needed to reduce the risk of reuse and mitigate local supply shortages. Here we review the available literature concerning use of germicidal ultraviolet-C (UV-C) light to decontaminate N95 masks. We propose a practical method for repeated point-of-use decontamination using commercially-available UV-C crosslinker boxes from molecular biology laboratories to expose each side of the mask to 800–1200 mJ/cm2of UV-C. We measure the dose that penetrated to the interior of the respirators and model the potential germicidal action on SARS-CoV-2. Our experimental results, in combination with modeled data, suggest that a two-minute UV-C treatment cycle should induce a >3-log-order reduction in viral bioburden on the surface of the respirators, and a 2-log order reduction throughout the interior. The resulting exposure is 100-fold less than the dose expected to damage the masks, facilitating repeated decontamination. As such, UV-C germicidal irradiation (UVGI) is a practical strategy for small-scale point-of-use decontamination of N95s.
The association between thrombocytosis and subtype of lung cancer: a systematic review and meta-analysis
Authors: Barlow Melissa , Hamilton Willie , Ukoumunne Obioha Chukwunyere , Bailey Sarah Elizabeth Rose
Published: June 2020

Background

Thrombocytosis is associated with poor lung cancer prognosis and has recently been identified as having a high predictive value in lung cancer detection. Lung cancer has multiple histological and genetic subtypes and it is not known whether platelet levels differ across subtypes.

Methods

PubMed and Embase were systematically searched for studies that reported pre-treatment platelet count, as either averages or proportion of patients with thrombocytosis, by histological subtype of lung cancer. Suitable studies were synthesised in meta-analyses; subgroup analyses examined for differences across subtypes.

Results

The prevalence of pre-treatment thrombocytosis across all lung cancer patients was 27% (95% CI: 17 to 37%). By subtype, this was 22% (95% CI: 7 to 41%) for adenocarcinoma (ADC), 28% (95% CI: 15 to 43%) for squamous cell carcinoma (SCC), 36% (95% CI: 13 to 62%) for large cell carcinoma, and 30% (95% CI: 8 to 58%) for small cell lung cancer (SCLC). The pooled mean platelet count for lung cancer patients was 289×109 /L (95% CI: 268 to 311). By subtype, this was 282×109 /L (95% CI: 259 to 306) for ADC, 297×109 /L (95% CI: 238 to 356) for SCC, 290×109 /L (95% CI: 176 to 404) for LCC, and 293×109 /L (95% CI: 244 to 342) for SCLC. There was no difference in thrombocytosis prevalence (p=0.76) or mean platelet count (p=0.96) across the subtypes.

Conclusion

We report no evidence of differences in platelet levels across the major subtypes of lung cancer. A high platelet level is likely to be generic across all lung cancer subtypes.

KEY MESSAGES

What is the key question?

Which (if any) subtype(s) of lung cancer are more associated with thrombocytosis?

What is the bottom line?

This can facilitate lung cancer diagnostics and provide insights into the biological mechanism between lung cancer and thrombocytosis.

Why read on?

This is the first systematic review to compare platelet count across different subtypes of lung cancer, combining data from 9,891 patients across 38 studies.
Clinical signs, symptoms, perceptions and impact on quality of life of patients suffering peri-implant diseases: a university-representative cross-sectional study
Authors: Romandini Mario , Lima Cristina , Pedrinaci Ignacio , Araoz Ana , Soldini Maria Costanza , Sanz Mariano
Published: June 2020

Aim

To study the symptoms and perception reported by patients with peri-implant diseases, as well as their signs and their potential impact on the oral health quality of life.

Materials and Methods

240 randomly selected patients were invited to participate. As part of the history assessment, the patient OHIP-14Sp was evaluated together with, for each implant, the patient perception regarding the peri-implant health status and the history of pain, spontaneous discomfort, bleeding, suppuration, swelling and discomfort during brushing. As part of the clinical examination, the following potential signs of peri-implant diseases were collected: probing pocket depth (PPD), mucosal dehiscence (MD), extent of BoP, presence of SoP, and visual signs of redness and swelling. Those parameters were analyzed in relation to the actual peri-implant health diagnosis.

Results

99 patients with a total of 458 dental implants were studied. Even in case of peri-implantitis, 88.89% of the implants were perceived by the patients as healthy. The total OHIP-14Sp sum score did not differ in relation to the peri-implant health diagnosis. Increased reports of spontaneous discomfort, bleeding, swelling and discomfort during brushing were observed in presence of disease. However, only a minor proportion of implants with peri-implant diseases presented symptoms. PPD≥6 mm was more frequent in diseased than in healthy implants(p<0.01), while PPD≥8 in pre-periimplantitis/peri-implantitis than in healthy/mucositis implants(p<0.01). Implants with peri-implantitis showed higher MD than implants without peri-implantitis(p<0.01).

Conclusions

Peri-implant diseases are in most cases asymptomatic and not perceived by the patients. Despite being unable to accurately discriminate between peri-implant mucositis and peri-implantitis, PPD and MD resulted as the only two clinical signs associated with pre-periimplantitis/peri-implantitis.
Effectiveness of stay-in-place-orders during COVID-19 pandemic: Evidence from US border counties
Authors: Devaraj Srikant , Patel Pankaj C.
Published: June 2020

Recent studies on US counties, with varying effect sizes, show that stay-in-place-orders (SIPOs) are associated with a decline in new COVID-19 cases. Our estimation approach relies on county-pairs across state-borders where one state has SIPO whereas the other state does not, controls for matched county-pair fixed effects and day of observation fixed-effects. The county-pair sample from southern, mid-western, and mountain region states (from March 1, 2020 to April 25, 2020) shows that daily COVID-19 incidence case growth rate is 1.994 percentage points lower for counties in SIPO states relative to those bordering in non-SIPO states. Specifically, we find SIPO reduced daily growth rates by 1.97, 2.14, 2.03, and 2.27 percentage points after 1 to 5 days, 6 to 10 days, 11 to 15 days, and 16 to 20 days, respectively. Our effect sizes are much smaller than in the previous studies with the caveat that states in the northeast and on the west coast could not be included in the border county-pair specification. We find limited evidence of heterogeneous effects in counties with a higher population density, percentage of black or Hispanic residents, proportion of population over 65 years, and social association rates in a county. Nor do we find evidence of meaningful differences in effects of SIPO by county Gini index, unemployment, or GDP. The results of this study could further inform policymakers in making decisions on SIPO extensions or lifting of such orders.

JEL

H75; I18
An analysis of SARS-CoV-2 viral load by patient age
Authors: Jones Terry C. , Mühlemann Barbara , Veith Talitha , Biele Guido , Zuchowski Marta , Hofmann Jörg , Stein Angela , Edelmann Anke , Corman Victor Max , Drosten Christian
Published: June 2020

As children are under-represented in current studies aiming to analyse transmission of SARS-coronavirus 2 (SARS-CoV-2), their contribution to transmission is unclear. Viral load, as measured by RT-PCR, can inform considerations regarding transmission, especially if existing knowledge of viral load in other respiratory diseases is taken into account. RT-PCR threshold cycle data from 3303 patients who tested positive for SARS-CoV-2 (out of 77,996 persons tested in total, drawn from across Germany) were analysed to examine the relationship between patient age and estimated viral load. Two PCR systems were used. In data from the PCR system predominantly used for community and cluster screening during the early phase of the epidemic (Roche LightCycler 480 II), when such screening was frequent practice, viral loads do not differ significantly in three comparisons between young and old age groups (differences in log10 viral loads between young and old estimated from raw viral load data and a Bayesian mixture model of gamma distributions collectively range between −0.11 and −0.43). Data from a second type of PCR system (Roche cobas 6800/8800), introduced into diagnostic testing on March 16, 2020 and used during the time when household and other contact testing was reduced, show a credible but small difference in the three comparisons between young and old age groups (differences, measured as above, collectively range between −0.43 and −0.83). This small difference may be due to differential patterns of PCR instrument utilization rather than to an actual difference in viral load. Considering household transmission data on influenza, which has a similar viral load kinetic to SARS-CoV-2, the viral load differences between age groups observed in this study are likely to be of limited relevance. Combined data from both PCR instruments show that viral loads of at least 250,000 copies, a threshold we previously established for the isolation of infectious virus in cell culture at more than 5% probability, were present across the study period in 29.0% of kindergarten-aged patients 0-6 years old (n=38), 37.3% of those aged 0-19 (n=150), and in 51.4% of those aged 20 and above (n=3153). The differences in these fractions may also be due to differences in test utilization. We conclude that a considerable percentage of infected people in all age groups, including those who are pre- or mild-symptomatic, carry viral loads likely to represent infectivity. Based on these results and uncertainty about the remaining incidence, we recommend caution and careful monitoring during gradual lifting of non-pharmaceutical interventions. In particular, there is little evidence from the present study to support suggestions that children may not be as infectious as adults.
Cognitive impairment is a common comorbidity in COVID-19 deceased patients. A hospital-based retrospective cohort study
Authors: Martín-Jiménez Paloma , Muñoz-García Mariana I. , Seoane David , Roca-Rodríguez Lucas , García-Reyne Ana , Lalueza Antonio , Maestro Guillermo , Folgueira Dolores , Blanco-Palmero Víctor A. , Martín Alejandro Herrero-San , Llamas-Velasco Sara , Pérez-Martínez David A. , González-Sánchez Marta , Villarejo-Galende Alberto
Published: June 2020

Introduction

Little is known about the relation of cognitive impairment (CI) to COVID-19 mortality. Here, we analyse the frequency of CI in deceased COVID-19 patients.

Methods

We included 477 adult cases that died after admission from March 1 to March 31, 2020: 281 with confirmed COVID-19, 58 probable COVID-19, and 138 who died of other causes.

Results

The number of comorbidities was high in the confirmed COVID-19, and CI was common (30%: 21.1% dementia; 8.9% mild cognitive impairment). Subjects with CI were older, more lived in nursing homes and had shorter times from symptom onset to death than those without CI. COVID-19 patients with CI were rarely admitted to the ICU and fewer received non-invasive mechanical ventilation, but palliative care was provided more often.

Conclusions

Dementia is a frequent comorbidity in COVID-19 deceased patients. The burden of COVID-19 in the dementia community will be high.
Benchmarking Deep Learning Models and Automated Model Design for COVID-19 Detection with Chest CT Scans
Authors: He Xin , Wang Shihao , Shi Shaohuai , Chu Xiaowen , Tang Jiangping , Liu Xin , Yan Chenggang , Zhang Jiyong , Ding Guiguang
Published: June 2020

COVID-19 pandemic has spread all over the world for months. As its transmissibility and high pathogenicity seriously threaten people’s lives, the accurate and fast detection of the COVID-19 infection is crucial. Although many recent studies have shown that deep learning based solutions can help detect COVID-19 based on chest CT scans, there lacks a consistent and systematic comparison and evaluation on these techniques. In this paper, we first build a clean and segmented CT dataset called Clean-CC-CCII by fixing the errors and removing some noises in a large CT scan dataset CC-CCII with three classes: novel coronavirus pneumonia (NCP), common pneumonia (CP), and normal controls (Normal). After cleaning, our dataset consists of a total of 340,190 slices of 3,993 scans from 2,698 patients. Then we benchmark and compare the performance of a series of state-of-the-art (SOTA) 3D and 2D convolutional neural networks (CNNs). The results show that 3D CNNs outperform 2D CNNs in general. With extensive effort of hyperparameter tuning, we find that the 3D CNN model DenseNet3D121 achieves the highest accuracy of 88.63% (F1-score is 88.14% and AUC is 0.940), and another 3D CNN model ResNet3D34 achieves the best AUC of 0.959 (accuracy is 87.83% and F1-score is 86.04%). We further demonstrate that the mixup data augmentation technique can largely improve the model performance. At last, we design an automated deep learning methodology to generate a lightweight deep learning model MNas3DNet41 that achieves an accuracy of 87.14%, F1-score of 87.25%, and AUC of 0.957, which are on par with the best models made by AI experts. The automated deep learning design is a promising methodology that can help health-care professionals develop effective deep learning models using their private data sets. Our Clean-CC-CCII dataset and source code are available at: https://github.com/HKBU-HPML/HKBU_HPML_COVID-19.
Does susceptibility to novel coronavirus (COVID-19) infection differ by age?: Insights from mathematical modelling
Authors: Omori Ryosuke , Matsuyama Ryota , Nakata Yukihiko
Published: June 2020

Among Italy, Spain, and Japan, the age distributions of novel coronavirus (COVID-19) mortality show only small variation even though the number of deaths per country shows large variation. To understand the determinant for this situation, we constructed a mathematical model describing the transmission dynamics and natural history of COVID-19 and analyzed the dataset of fatal cases of COVID-19 in Italy, Spain, and Japan. We estimated the parameter which describes the age-dependency of susceptibility by fitting the model to reported data, taking into account the effect of change in contact patterns during the outbreak of COVID-19, and the fraction of symptomatic COVID-19 infections. Our modelling study revealed that if the mortality rate or the fraction of symptomatic infections among all COVID-19 cases does not depend on age, then unrealistically different age-dependencies of susceptibilities against COVID-19 infections between Italy, Japan, and Spain are required to explain the similar age distribution of mortality but different basic reproduction numbers (R0). Variation of susceptibility by age itself cannot explain the robust age distribution in mortality by COVID-19 in those three countries, however it does suggest that the age-dependencies of i) the mortality rate and ii) the fraction of symptomatic infections among all COVID-19 cases determine the age distribution of mortality by COVID-19.
The ‘Icarus effect’ of preventative health behaviors
Authors: Carrignon Simon , Bentley R. Alexander , Silk Matthew , Fefferman Nina H.
Published: June 2020

1

Ongoing efforts to combat the global pandemic of COVID-19 via public health policy have revealed the critical importance of understanding how individuals understand and react to infection risks. We here present a model to explore how both individual observation and social learning are likely to shape behavioral, and therefore epidemiological, dynamics over time. Efforts to delay and reduce infections can compromise their own success, especially in populations with age-structure in both disease risk and social learning —two critical features of the current COVID-19 crisis. Our results concur with anecdotal observations of age-based differences in reactions to public health recommendations. We show how shifting reliance on types of learning affect the course of an outbreak, and could therefore factor into policy-based interventions.
Worries and concerns among healthcare workers during the coronavirus 2019 pandemic: a web-based cross-sectional survey
Authors: Sahashi Yuki , Endo Hirohisa , Sugimoto Tadafumi , Nabeta Takeru , Nishizaki Kimitaka , Kikuchi Atsushi , Matsumoto Shingo , Sato Hiroyuki , Goto Tadahiro , Hasegawa Kohei , Matsue Yuya
Published: June 2020

Background

Healthcare workers (HCWs) treating and caring for patients with emerging infectious diseases often experience psychological distress. However, the psychological impact and behavior change of the coronavirus disease 2019 (COVID-19) pandemic among HCWs are still unknown. This study aimed to investigate the worries and concerns of HCWs regarding the COVID-19 pandemic.

Methods

In this cross-sectional survey, a web-based questionnaire was distributed among HCWs working in hospitals or clinics across Japanese medical facilities from April 20 to May 1, 2020. The questionnaire comprised items on demographics, worries and concerns, perceptions regarding the sufficiency of information, and behavioral changes pertaining to the COVID-19 pandemic.

Results

A total of 4386 HCWs completed the survey; 1648 (64.7%) were aged 30-39 years, 2379 (54.2%) were male, and 782 (18.1%) were frontline HCWs, directly caring for patients with COVID-19 on a daily basis. 3500 HCWs (79.8%) indicated that they were seriously worried about the pandemic. The most frequent concern was the consequence of becoming infected on their family, work, and society (87.4%). Additionally, the majority (55.5%) had restricted social contact and almost all HCWs endorsed a shortage in personal protective equipment (median, 8/9 (interquartile range; 7-9) on a Likert scale). There was no significant difference in the degree of worry between frontline and non-frontline HCWs (8/9 (7-9) vs. 8/9 (7-9), p=0.25). Frontline HCWs, compared to non-frontline HCWs, were more likely to have the need to avoid contact with families and friends (24.8% vs. 17.8%, p<0.001) and indicated that they cannot evade their professional duty during the COVID-19 pandemic (9/9 (7-9) vs. 8/9 (6-9), p<0.001). Further, the extremely low proportion of frontline HCWs reported that they would take a leave of absence to avoid infection (1.2%).

Conclusions

Both frontline and non-frontline HCWs expressed comparable concerns regarding the COVID-19 pandemic. Because HCWs, especially frontline HCWs, reported that they cannot be obliged to do avoid their duty, effective mental health protection strategies should be developed and implemented for HCWs.
Integrated approach for risk management in servitization decision-making process
Authors: Dahmani Sarra , Boucher Xavier , Gourc Didier , Peillon Sophie , Marmier François
Published: June 2020

Purpose

The paper proposes an innovative systemic method helping decision-makers to control servitization transition process, through decision process risk diagnosis.

Design/methodology/approach

The proposed method is based on the modeling of decision processes and risk identification and analysis. This method was based on an action-research approach, in close relationship with two companies (SMEs). The paper develops the feasibility experiment at Automelec company.

Findings

The method was successfully implemented and delivered concrete diagnosis results.

Research limitations/implications

The generalization of the applicability of the method needs to be tested on several different cases.

Practical implications

The first practical implication is related to the efficiency of the method to help decision-makers in a servitization context to limit uncertainty and get a global view of the weaknesses of their decision-making process, it raises their awareness about servitization transition for their companies. Furthermore, the method also helps to explain the strategy of a servitization transition. It enhances the level of maturity of the decision process of the company, and can be used as a training/learning tool for managers.

Social implications

The results brought by the research contribute to give the decision-making boards for organization living a servitization transition and especially SMEs a better control over the servitization decision process and related risks, which will increase the economic stability of the company and its vision over long, medium and short horizons. This will bring positive impact on the overall economic and social environment and networks of the servitized SME, and enhance the confidence of coworkers, subcontractors and clients.

Originality/value

The first originality of the paper is related to the new way of considering risk, not only as an analysis criterion but as the central driver in steering a strategic transition for the company, such as servitization. The second originality of the study is about assessing risk occurrence over a decision-making process through decision reliability and decision confidence.
Using look-ahead plans to improve material flow processes on construction projects when using BIM and RFID technologies
Authors: Chen Qian , Adey Bryan T. , Haas Carl , Hall Daniel M.
Published: June 2020

Purpose

Building information modelling (BIM) and radio frequency identification (RFID) technologies have been extensively explored to improve supply chain visibility and coordination of material flow processes, particularly in the pursuit of Industry 4.0. It remains challenging, however, to effectively use these technologies to enable the precise and reliable coordination of material flow processes. This paper aims to propose a new workflow designed to include the use of detailed look-ahead plans when using BIM and RFID technologies, which can accurately track and match both the dynamic site needs and supply status of materials.

Design/methodology/approach

The new workflow is designed according to lean theory and is modeled using business process modeling notation. To digitally support the workflow, an integrated BIM-RFID database system is constructed that links information on material demands with look-ahead plans. The new workflow is then used to manage material flows in the erection of an office building with prefabricated columns. The performance of the new workflow is compared with that of a traditional workflow, using discrete event simulations. The input for the simulations was derived from expert opinion in semi-structured interviews.

Findings

The new workflow enables contractors to better observe on-site status and differences between the actual and planned material requirements, as well as to alert suppliers if necessary. The simulation results indicate that the new workflow has the potential to reduce the duration of the material flow processes by 16.1% compared with the traditional workflow.

Research limitations/implications

The new workflow is illustrated using a real-world-like situation with input data based on expert opinion. Although the workflow shows potential, it should be tested on a real-world site.

Practical implications

The new workflow allows project participants to combine detailed near-term look-ahead plans with BIM and RFID technologies to better manage material flow processes. It is particularly useful for the management of engineer-to-order components considering the dynamic site progress.

Originality/value

The research improves on existing research focused on using BIM and RFID technologies to improve material flow processes by showing how the workflow can be adapted to use detailed look-ahead plans. It reinforces data-driven construction material management practices through improved visibility and reliability in planning and control of material flow processes.
Improved 3D electromagnetic analytical model for planar induction heater with consideration of transverse edge effects
Authors: Messadi Mohammed , Hadjout Larbi , Ouazir Youcef , Bensaidane Hakim , Takorabet Noureddine , Lubin Thierry , Mezani Smail
Published: June 2020

Purpose

This paper aims to propose a new 3D electromagnetic model to compute translational motion eddy current in the conducting plate of a novel linear permanent magnet (PM) induction heater. The movement of the plate in a DC magnetic field created by a PM inductor generates induced currents that are at the origin of a heating power by Joule effect. These topologies have strong magnetic end effects. The analytical model developed in this work takes into account the finite length extremity effects of the conducting plate and the reaction field because of induced currents.

Design/methodology/approach

The developed model is based on the combination of the sub-domain’s method and the image’s theory. First, the magnetic field expressions because of the PMs are obtained by solving the three-dimensional Maxwell equations by the method of separation of variables, using a magnetic scalar potential formulation and a magnetic field strength formulation. Then, the motional eddy currents are computed using the Ampere law, and the finite length extremity effects of the conducting plate are taken into account using the image’s method. To analyze the accuracy of the proposed model, the obtained results are compared to those obtained from 3D finite element model (FEM) and from experimental tests performed on a prototype.

Findings

The results show that the developed analytical model is very accurate, even for geometries where the edge effects are very strong. It allows directly taking into account the finite length extremity effects (the transverse edge effects) of the conducting plate and the reaction field because of induced currents without the need of any correction factor. The proposed model also presents an important reduction in computation time compared to 3D finite element simulation, allowing fast analysis of linear PM induction heater.

Practical implications

The proposed electromagnetic analytical model can be used as a quick and accurate design tool for translational motion PM induction heater devices.

Originality/value

A new 3D analytical electromagnetic model, to find the induced power in the conducting plate of a novel translational motion induction heater has been developed. The studied heating device has a finite length and a finite width, which create edge effects that are not easily considered in calculation. The novelty of the presented method is the accurate 3D analytical model, which allows finding the real power heating and real distribution of the induced currents in the conducting plate without the need to use correction factor. The proposed model also takes into account the reaction field because of induced currents. In addition, the developed model improves an important reduction in the computation time compared with 3D FEM simulation.
Numerical solution of Lane-Emden type equations using Adomian decomposition method with unequal step-size partitions
Authors: Umesh Umesh , Kumar Manoj
Published: June 2020

Purpose

The purpose of this paper is to obtain the highly accurate numerical solution of Lane–Emden-type equations using modified Adomian decomposition method (MADM) for unequal step-size partitions.

Design/methodology/approach

First, the authors describe the standard Adomian decomposition scheme and the Adomian polynomials for solving nonlinear differential equations. After that, for the fast calculation of the Adomian polynomials, an algorithm is presented based on Duan’s corollary and Rach’s rule. Then, MADM is discussed for the unequal step-size partitions of the domain, to obtain the numerical solution of Lane–Emden-type equations. Moreover, convergence analysis and an error bound for the approximate solution are discussed.

Findings

The proposed method removes the singular behaviour of the problems and provides the high precision numerical solution in the large effective region of convergence in comparison to the other existing methods, as shown in the tested examples.

Originality/value

Unlike the other methods, the proposed method does not require linearization or perturbation to obtain an analytical and numerical solution of singular differential equations, and the obtained results are more physically realistic.
A multi-national validity analysis of the argumentativeness measure
Authors: Croucher Stephen Michael , Kelly Stephanie , Burkey Mark , Spencer Anthony , Gomez Oscar , Del Villar Carmencita , Eskiçorapçı Nadirabegim
Published: June 2020

Purpose

The argumentativeness measure has been used in more than a 100 studies since 1982. The measure was developed and validated within a US university/college student sample. Despite its intended use, the measure is regularly used outside of the US and outside of the university/college setting without tests of validity. There is also intense debate as to the dimensionality of the measure, with one camp defending the bi-dimensionality of the measure and another proposing uni-dimensionality. Therefore, the purpose of this study was to assess the utility of the measure outside of its intended population.

Design/methodology/approach

A total of seven samples were collected (n = 1860) from the UK, Germany, France, Turkey, the Philippines, Nicaragua and the US. In this study, Infante and Rancer’s (1982) original 20-item argumentativeness measure was used to assess argumentativeness. Confirmatory factor analyses was used to test content validity.

Findings

Fit statistics were consistently poor for the unidimensional factor structure. As there is debate as to whether the measure is uni or bi-dimensional, a bi-dimensional fit was also analysed. The measure performed slightly better in each sample using a bi-dimensional factor structure. However, fit statistics were still poor for each sample.

Research limitations/implications

Specifically, the seven samples are convenience samples. While such a sampling technique does limit the generalizability of a study’s findings, convenience samples are common when using the argumentativeness measure. These results present avenues for exploring the dimensionality of the argumentativeness measure and for revisiting cross-cultural examinations of argumentativeness.

Practical implications

Factor structure is a critical issue in validity. Whether authors specify their prediction or not, factor structure is always hypothesized as part of a study when measurements are used, and therefore, should be examined in every study as part of the scientific process. Making claims about human behaviour based upon measures with mis-specified factor structures or other validity issues can lead to the perpetuation of misinformation within the literature.

Originality/value

This is one of the few studies to empirically explore the psychometric properties of one of the most used measures in argument/conflict research. In doing so, this study enhances the understanding of decades of argumentativeness research.