bluuebunny/crossref_metadata_2025 huggingface dataset:
Can the mind wander intentionally?
Authors: Murray Samuel , Krasich Kristina
Published: November 2020

Mind wandering is typically operationalized as task‐unrelated thought. Some argue for the need to distinguish between unintentional and intentional mind wandering, where an agent voluntarily shifts attention from task‐related to task‐unrelated thoughts. We reveal an inconsistency between the standard, task‐unrelated thought definition of mind wandering and the occurrence of intentional mind wandering (together with plausible assumptions about tasks and intentions). This suggests that either the standard definition of mind wandering should be rejected or that intentional mind wandering is an incoherent category. Solving this puzzle is critical for advancing theoretical frameworks of mind wandering.
Extreme C‐terminal element of SprA serine integrase is a potential component of the “molecular toggle switch” which controls the recombination and its directionality
Authors: Abe Kimihiro , Takahashi Takumi , Sato Tsutomu
Published: November 2020

In Bacillus subtilis, a sporulation‐related gene, spsM, is disrupted by SPβ prophage, but reconstituted during sporulation through SPβ excision. The spsM reconstitution is catalyzed by a site‐specific DNA recombinase, SprA, and its cognate recombination directionality factor, SprB. SprB interacts with SprA, directing the SprA‐mediated recombination reaction from integration to excision; however, the details of the directionality control remains unclear. Here, we demonstrate the importance of the extreme C‐terminal region (ECT) of SprA in the DNA recombination and directionality control. We created a series of SprA C‐terminal deletants and examined their DNA‐binding and recombination activities. Deletions in the ECT caused a loss of integration and excision activity, the magnitudes of which positively correlated with the deletion size. Gel shift study revealed that the loss of the integration activity was attributable to the failure of synaptic complex formation. The excision deficiency was caused by defective interaction with SprB. Moreover, alanine scanning analysis revealed that Phe532 is essential to interact with SprB. SprAF532A, therefore, showed almost no excision activity, while retaining the integration activity. Collectively, these results suggest that the ECT plays the crucial roles in the interaction of SprA with SprB and possibly in the directional control of the recombination.
Incidence and risk factors of kidney allograft loss due to BK nephropathy in the pediatric population: A retrospective analysis of the UNOS/OPTN database
Authors: Patel Het , Rodig Nancy , Agrawal Nikhil , Cardarelli Francesca
Published: November 2020

Background

BK virus infection can lead to graft dysfunction and loss in kidney transplant recipients. Risk factors for BKV and BKVN have been inadequately studied in children. Here, we evaluate the incidence and risk factors of allograft loss due to BKVN in the pediatric population of the UNOS data set.

Methods

We conducted a retrospective cohort analysis of the UNOS database and identified all pediatric recipients of kidney transplantation between 2000 and 2018. We compared donor and recipient characteristics, including cause of ESRD, among patients who lost their graft due to BKVN or other causes, and those with functioning allograft. Kaplan–Meier curve and Cox regression analysis were performed to evaluate the risk factors.

Results

A total of 66 patients (0.47%) suffered graft failure from BKVN. Older age, male gender, HLA mismatch, and rejection at 1 year were significantly associated with BKVN graft failure, compared to recipients with functioning allograft. In comparison with graft loss due to other causes, male gender, higher HLA mismatch, rejection in 1st year and tacrolimus use at discharge were significantly associated with BKVN graft loss. Recipients who received mycophenolate at time of discharge were at reduced risk for BKVN graft failure. Compared to graft failure from other causes, BKVN graft failure had shorter death censored graft survival [P = .001]. ESRD due to urologic causes and Alport syndrome had higher rate of BKVN graft failure.

Conclusion

Incidence of graft loss from BKVN in the pediatric population was 10.2 per 10 000 patient‐years in this study. BKVN is associated with early allograft failure in the pediatric population, compared to other causes of graft loss. Male gender, HLA mismatch, rejection in 1st year, and urological cause of ESRD are risk factors for graft failure from BKVN in children.
Pandemic risk: Impact, modeling, and transfer
Authors: Qiu Joseph
Published: November 2020

COVID‐19 has proven that pandemic risk deems to the type of catastrophe risk that needs to be treated seriously, by both society and the insurance industry. A key element to measure, manage, and transfer pandemic risk is the modeling capability. This paper first reviews the insured loss from COVID‐19 and the impact on the insurance industry. Then, current pandemic risk modeling capabilities and how insurance industry uses these models are evaluated. Some suggestions are made in terms of how these models can be improved in the future and how they can assist in insuring the pandemic risk. Finally, the nonmodeling elements of pandemic risk transfer and the government's role are discussed.
Christmas Trees, Presidents, and Mass Shootings: Explaining Gun Purchases in the South and Non‐South
Authors: LaPlant Kristina M. , Lee Keith E. , LaPlant James T.
Published: November 2020

Objective

This article explores the factors that influence gun purchases in the United States with particular attention to regional differences between the South and non‐South.

Methods

We use data collected by the Federal Bureau of Investigation's National Instant Criminal Background Check System to conduct a time‐series cross‐sectional analysis of monthly firearm background checks, a proxy for gun purchases, in each state from January 1999 to May 2020.

Results

Throughout the data series, average gun purchases in the South dwarf those in the non‐South. Spikes in gun sales are positively associated with Democratic presidencies, Christmas holidays, mass shootings, and news coverage of mass shootings. Gun purchases have also spiked nationwide in the wake of the coronavirus pandemic, though most notably in the South.

Conclusion

Our findings speak to the powerful role fear plays in motivating gun purchases, the magnitude of political polarization in the United States, and the regional distinctiveness of the South.
Guiding lights
Authors: Sokol Joshua
Published: November 2020

Precise maps of millions of bright quasars show our place in the cosmos as never before.
Identification of Integrator-PP2A complex (INTAC), an RNA polymerase II phosphatase
Authors: Zheng Hai , Qi Yilun , Hu Shibin , Cao Xuan , Xu Congling , Yin Zhinang , Chen Xizi , Li Yan , Liu Weida , Li Jie , Wang Jiawei , Wei Gang , Liang Kaiwei , Chen Fei Xavier , Xu Yanhui
Published: November 2020

Dephosphorylating RNA polymerase II

Transcription in metazoans requires coordination of multiple factors to control the progression of polymerases and the integrity of their RNA products. Zheng
et al.
identified a new dual-enzyme complex called INTAC, which is composed of protein phosphatase 2A (PP2A) core enzyme and the multisubunit RNA endonuclease Integrator. Structural and functional studies show that INTAC functions as a noncanonical PP2A holoenzyme that dephosphorylates the C-terminal domain of RNA polymerase II to attenuate transcription. This study provides a direct connection between PP2A-mediated dephosphorylation and transcriptional regulation, two fundamental cellular processes.

Science
, this issue p.
eabb5872
Infection fatality risk for SARS-CoV-2 in community dwelling population of Spain: nationwide seroepidemiological study
Authors: Pastor-Barriuso Roberto , Pérez-Gómez Beatriz , Hernán Miguel A , Pérez-Olmeda Mayte , Yotti Raquel , Oteo-Iglesias Jesús , Sanmartín Jose L , León-Gómez Inmaculada , Fernández-García Aurora , Fernández-Navarro Pablo , Cruz Israel , Martín Mariano , Delgado-Sanz Concepción , Fernández de Larrea Nerea , León Paniagua Jose , Muñoz-Montalvo Juan F , Blanco Faustino , Larrauri Amparo , Pollán Marina
Published: November 2020

Objective

To estimate the infection fatality risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), based on deaths with confirmed coronavirus disease 2019 (covid-19) and excess deaths from all causes.

Design

Nationwide seroepidemiological study.

Setting

First wave of covid-19 pandemic in Spain.

Participants

Community dwelling individuals of all ages.

Main outcome measures

The main outcome measure was overall, and age and sex specific, infection fatality risk for SARS-CoV-2 (the number of covid-19 deaths and excess deaths divided by the estimated number of SARS-CoV-2 infections) in the community dwelling Spanish population. Deaths with laboratory confirmed covid-19 were obtained from the National Epidemiological Surveillance Network (RENAVE) and excess all cause deaths from the Monitoring Mortality System (MoMo), up to 15 July 2020. SARS-CoV-2 infections in Spain were derived from the estimated seroprevalence by a chemiluminescent microparticle immunoassay for IgG antibodies in 61 098 participants in the ENE-COVID nationwide seroepidemiological survey between 27 April and 22 June 2020.

Results

The overall infection fatality risk was 0.8% (19 228 of 2.3 million infected individuals, 95% confidence interval 0.8% to 0.9%) for confirmed covid-19 deaths and 1.1% (24 778 of 2.3 million infected individuals, 1.0% to 1.2%) for excess deaths. The infection fatality risk was 1.1% (95% confidence interval 1.0% to 1.2%) to 1.4% (1.3% to 1.5%) in men and 0.6% (0.5% to 0.6%) to 0.8% (0.7% to 0.8%) in women. The infection fatality risk increased sharply after age 50, ranging from 11.6% (8.1% to 16.5%) to 16.4% (11.4% to 23.2%) in men aged 80 or more and from 4.6% (3.4% to 6.3%) to 6.5% (4.7% to 8.8%) in women aged 80 or more.

Conclusion

The increase in SARS-CoV-2 infection fatality risk after age 50 appeared to be more noticeable in men than in women. Based on the results of this study, fatality from covid-19 was greater than that reported for other common respiratory diseases, such as seasonal influenza.
Community engagement approaches for Indigenous health research: recommendations based on an integrative review
Authors: Lin Chu Yang , Loyola-Sanchez Adalberto , Boyling Elaine , Barnabe Cheryl
Published: November 2020

Objective

Community engagement practices in Indigenous health research are promoted as a means of decolonising research, but there is no comprehensive synthesis of approaches in the literature. Our aim was to assemble and qualitatively synthesise a comprehensive list of actionable recommendations to enhance community engagement practices with Indigenous peoples in Canada, the USA, Australia and New Zealand.

Design

Integrative review of the literature in medical (Medline, Cumulative Index to Nursing and Allied Health Literature and Embase) and Google and WHO databases (search cut-off date 21 July 2020).

Article selection

Studies that contained details regarding Indigenous community engagement frameworks, principles or practices in the field of health were included, with exclusion of non-English publications. Two reviewers independently screened the articles in duplicate and reviewed full-text articles.

Analysis

Recommendations for community engagement approaches were extracted and thematically synthesised through content analysis.

Results

A total of 63 studies were included in the review, with 1345 individual recommendations extracted. These were synthesised into a list of 37 recommendations for community engagement approaches in Indigenous health research, categorised by stage of research. In addition, activities applicable to all phases of research were identified: partnership and trust building and active reflection.

Conclusions

We provide a comprehensive list of recommendations for Indigenous community engagement approaches in health research. A limitation of this review is that it may not address all aspects applicable to specific Indigenous community settings and contexts. We encourage anyone who does research with Indigenous communities to reflect on their practices, encouraging changes in research processes that are strengths based.
Serum 25-hydroxyvitamin D levels in relation to lipids and clinical outcomes in pregnant women with gestational diabetes mellitus: an observational cohort study
Authors: Chen Wenqing , Li Yuan , Gao Bo , Li Jie , Zheng Mingming , Chen Xiaotian
Published: November 2020

Objective

The aim of the present study was to investigate whether 25-hydroxyvitamin D (25(OH)D) status at 24–28 weeks is associated with blood lipids and pregnancy outcomes in patients with gestational diabetes mellitus (GDM).

Design

We performed an observational cohort study.

Setting

The study was conducted in China.

Participants

A total of 261 pregnant women diagnosed with GDM at 24–28 weeks of gestation in our hospital were included between June 2015 and December 2017. According to the levels of 25(OH)D, the women were divided into the G1 (<20 ng/mL) and G2 (≥20 ng/mL) groups. The levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), TG/HDL-c and TC/HDL-c ratios were obtained from medical records. Pregnancy outcomes included gestational weeks of birth and delivery mode. Newborn information included birth weight and body length. Differences between groups were tested with adjusted multiple linear regression.

Results

The serum levels of 25(OH)D (14.1±3.4 ng/mL vs 28.5±6.5 ng/mL, p<0.001), TC (5.3±0.9 vs 5.6±0.8, p=0.006), HDL-c (1.8±0.4 vs 1.9±0.4, p=0.046) and LDL-c (2.5±0.6 vs 2.7±0.7, p=0.015) in the G2 group were significantly higher than those in G1 group, while TG/HDL-c ratios (1.43±0.7 vs 1.26±0.7, p=0.035) were significantly higher in the G1 group. Moreover, we failed to find a significant difference in pregnancy outcomes of mothers and newborns among the two groups (p>0.05). In models adjusting for maternal age, parity, height, blood pressure, socioeconomic status, educational attainment, pre-pregnancy body mass index, season and gestational age, maternal 25(OH)D was associated with TG/HDL-c ratios (B=−0.016; 95% CI= −0.025 to –0.006).

Conclusion

We found that there was no relationship between vitamin D and pregnancy/neonatal outcomes in our study. Maternal 25(OH)D at 24–28 weeks was inversely associated with TG/HDL-c ratios.
Assessment of patient and provider attitudes towards therapeutic drug monitoring to improve medication adherence in low-income patients with hypertension: a qualitative study
Authors: Schesing Kevin B , Chia Ricardo , Elwood Bryan , Halm Ethan A , Lee Simon J Craddock , Lodhi Hamza , Wu Bryan , Sharma Shishir , Smith Scott A , Jarrett Robin B , Das Sandeep R , Vongpatanasin Wanpen
Published: November 2020

Objectives

Previous studies have implicated therapeutic drug monitoring (TDM), by measuring serum or urine drug levels, as a highly reliable technique for detecting medication non-adherence but the attitudes of patients and physicians toward TDM have not been evaluated previously. Accordingly, we solicited input from patients with uncontrolled hypertension and their physicians about their views on TDM.

Design

Prospective analysis of responses to a set of questions during semistructured interviews.

Setting

Outpatient clinics in an integrated health system which provides care for a low-income, uninsured population.

Participants

Patients with uncontrolled hypertension with either systolic blood pressure of at least 130 mm Hg or diastolic blood pressure of at least 80 mm Hg despite antihypertensive drugs and providers in the general cardiology and internal medicine clinics.

Primary and secondary outcome measures

Attitudes towards TDM and the potential impact on physician–patient relationship.

Results

We interviewed 11 patients and 10 providers and discussed the findings with 13 community advisory panel (CAP) members. Of the patients interviewed, 91% (10 of 11) and all 10 providers thought TDM was a good idea and should be used regularly to better understand the reasons for poorly controlled hypertension. However, 63% (7 of 11) of patients and 20% of providers expressed reservations that TDM could negatively impact the physician–patient relationship. Despite some concerns, the majority of patients, providers and CAP members believed that if test results are communicated without blaming patients, the potential benefits of TDM in identifying suboptimal adherence and eliciting barriers to adherence outweighed the risks.

Conclusion

The idea of TDM is well accepted by patients and their providers. TDM information if delivered in a non-judgmental manner, to encourage an honest conversation between patients and physicians, has the potential to reduce patient–physician communication obstacles and to identify barriers to adherence which, when overcome, can improve health outcomes.
Deoxynucleoside therapy for respiratory involvement in adult patients with thymidine kinase 2-deficient myopathy
Authors: Hernandez-Voth Ana , Sayas Catalan Javier , Corral Blanco Marta , Castaño Mendez Alba , Martin Miguel Angel , De Fuenmayor Fernandez de la Hoz Carlos , Villena Garrido Victoria , Dominguez-Gonzalez Cristina
Published: November 2020

Background

Recessive mutations in the thymidine kinase 2 (TK2)gene cause a rare mitochondrial myopathy, frequently with severe respiratory involvement. Deoxynucleoside therapy is currently under investigation.

Research question

What is the impact of nucleosides in respiratory function in patients with TK2-deficient myopathy?

Study design and methods

Retrospective observational study of patients treated with deoxycytidine and deoxythymidine. Evaluations were performed every 3 to 4 months after treatment during approximately 30 months. Forced vital capacity (FVC), maximuminspiratory and expiratory pressures (MIP/MEP), sniff nasal inspiratory pressure (SNIP), cough peak flow (CPF), arterial blood gas and nocturnal pulse oximeter (SpO2) were collected.

Results

We studied six patients, five of which were women, with a median age at onset of symptoms was 35.8 (range 5 to 60) years old. Patients presented a restrictive ventilatory pattern (median FVC of 50 (26 to 71)%) and severe neuromuscular respiratory weakness (MIP 38 (12 to 47)% and SNIP 14 (8 to 19) cmH2O). Four patients required ventilatory support before starting the treatment. FVC improved by 6%, proportion of sleep time with SpO2 <90% diminished from 14% to 0%, CPF increased by 23%, MEP increased by 73%, production and management of bronchial secretions improved and respiratory infections diminished.

Interpretation

Early detection of respiratory involvement requires an active search, even in asymptomatic patients. The nucleosides therapy may improve respiratory function, and stabilise the loss of respiratory capacity.
A blood biomarker and clinical correlation cohort study protocol to diagnose sports-related concussion and monitor recovery in elite rugby
Authors: Kearns Jamie , Ross Aisling M , Walsh Darragh R , Cahalane Rachel M , Hinchion Rita , Ryan Maria C , Conway Elaine , Comyns Tom M , Kenny Ian C , O’Connor Eibhlís M , McGourty Kieran D , Mulvihill John Joseph Eugene
Published: November 2020

Introduction

In professional rugby, sports-related concussion (SRC) remains the most frequent time loss injury. Therefore, accurately diagnosing SRC and monitoring player recovery, through a multi-modal assessment process, is critical to SRC management. In this protocol study, we aim to assess SRC over multiple time points post-injury to determine the value of multi-modal assessments to monitor player recovery. This is of significance to minimise premature return-to-play and, ultimately, to reduce the long-term effects associated with SRC. The study will also establish the logistics of implementing such a study in a professional setting to monitor a player’s SRC recovery.

Methods and analysis

All players from the participating professional rugby club within the Irish Rugby Football Union are invited to participate in the current study. Player assessment includes head injury assessment (HIA), neuropsychometric assessment (ImPACT), targeted biomarker analysis and untargeted biomarker analysis. Baseline HIA, ImPACT, and blood draws are performed prior to the start of playing season. During the baseline tests, player’s complete consent forms and an SRC history questionnaire. Subsequently, any participant that enters the HIA process over the playing season due to a suspected SRC will be clinically assessed (HIA and ImPACT) and their blood will be drawn within 3 days of injury, 6 days post-injury, and 13 days post-injury.

Ethics and dissemination

Ethical approval was attained from the Science and Engineering Research Ethics Committee, University of Limerick (Approval Code: 2018_06_11_S&E). On completion of the study, further manuscripts will be published to present the results of the tests and their ability to measure player recovery from SRC.

Trial registration number

NCT04485494.
Risk for cardiovascular events following ‘microsize’ versus usual myocardial infarctions
Authors: Almarzooq Zaid I , Colantonio Lisandro D , Okin Peter M , Richman Joshua S , Brown Todd M , Levitan Emily B , Bryan Joanna , Safford Monika M
Published: November 2020

Background

Microsize myocardial infarction (MI) is a recently described phenomenon that meets rigorous criteria for MI with very low peak troponin elevations. We aim to compare the risk for cardiovascular events and mortality following microsize versus usual MIs.

Methods and results

Prospective cohort analysis of REasons for Geographic And Racial Differences in Stroke (REGARDS) study participants without a history of coronary heart disease (CHD) who had an incident MI between 2003 and 2015. Incident MIs were classified as microsize MI (peak troponin <0.5 ng/mL) or usual MI (peak troponin ≥0.5 ng/mL). Participants were followed for a composite of cardiovascular events that included recurrent MI, coronary revascularisation, fatal CHD and heart failure, and all-cause mortality. Overall, 1024 participants with an incident MI were included in the analysis (328 with microsize MI and 696 with usual MI). Participants with microsize MI were more likely to be older and black. The multivariable-adjusted adjustment HR for cardiovascular events among participants with microsize versus usual MI after a median follow-up of 1.7 years was 1.11 (95% CI 0.86 to 1.44). The multivariable-adjusted HR for all-cause mortality after 28 days from incident MI among participants with microsize versus usual MI after a median follow-up of 3.6 years was 1.09 (95% CI 0.81 to 1.45).

Conclusion

Microsize MIs have a prognostic value for future cardiovascular events and mortality comparable to usual MIs. These findings should encourage clinicians to initiate secondary prevention strategies in patients with microsize MI until this emerging clinical entity is better understood.
Development of a lateral ultrasound‐guided approach for the radial, ulnar, median and musculocutaneous (RUMM) nerve block in a calf undergoing surgical fixation of the antebrachium
Authors: Trujanovic Robert , Otero Pablo E , Larenza Menzies Maria Paula , Gasparik‐Küls Nina
Published: November 2020

A 26‐day‐old Pustertaler Sprinzer calf was referred to the ruminant clinic of the Veterinary University of Vienna for internal fixation of a suspected traumatic radius–ulnar fracture of the left forelimb. Preanaesthetic medication consisted of xylazine 0.06 mg/kg and ketamine 6 mg/kg intramuscularly, followed by induction of anaesthesia with ketamine 2.7 mg/kg intravenously. Anaesthesia was maintained with isoflurane in oxygen. A modified lateral ultrasound‐guided radial, ulnar, median and musculocutaneous (RUMM) block was performed using 0.3 ml/kg bupivacaine 0.5 per cent. Total surgical time was 385 minutes. Vital parameters remained stable throughout surgery, with no rescue analgesia required at any point. Recovery from anaesthesia was uneventful. The calf received morphine 0.1 mg/kg intramuscularly every four hours for the following four days. Additionally, carprofen 1.4 mg/kg intramuscularly was administered once daily for the following seven days. Fifty‐one days after surgical stabilisation, the plate was removed, and the calf was discharged home. The described modified lateral RUMM block using bupivacaine 0.5 per cent provided analgesia for at least 6.5 hours.
John Clewlow
Authors: Lanyon Lance , Jones Bruce Vivash
Published: November 2020

A practising veterinary surgeon whose interest and encyclopaedic knowledge about veterinary history was internationally recognised. As a speaker, his after dinner speeches were legendary.
Synthesis towards Future-Fittest for mature forest sector multinationals
Authors: Hansen Eric , Kangas Jyrki , Hujala Teppo
Published: November 2020

The circular bioeconomy represents a societal paradigm shift and transition challenge that inevitably influences how companies act in their evolving operational environment. The disruptive features may be particularly difficult to foresee and tackle strategically in companies with long-term operations and a relatively stable marketplace position, such as firms operating in the forest sector. Here we consider large forest sector companies in a circular bioeconomy sphere and scrutinize opportunities to hasten their sociotechnical transition pathway with a combination of open foresight and open innovation activities. We present a synthesis drawn from contemporary strategic business management literature and adapt that to forest sector multinationals. A greater openness to the actors, knowledge, and expertise outside the forest sector may be an essential element of successful bioeconomy transition for incumbent forest sector firms. This requires leadership to shift culture and an investment in the skills and expertise held by company employees. Increased investment in human capital and embracing a broader network of collaborators may pave the way for forest industry companies towards sophisticated corporate foresight and open innovation, corresponding to Future-Fittest status.
Bifurcations of Critical Periods for a Class of Quintic Liénard Equation
Authors: Yu Zhiheng , Liu Lingling
Published: November 2020

In this paper, we investigate a quintic Liénard equation which has a center at the origin. We give the conditions for the parameters for the isochronous centers and weak centers of exact order. Then, we present the global phase portraits for the system having isochronous centers. Moreover, we prove that at most four critical periods can bifurcate and show with appropriate perturbations that local bifurcation of critical periods occur from the centers.
Chaos Synchronization of Fractional-Order Lur’e Systems
Authors: Bouridah Mohammed Salah , Bouden Toufik , Yalçin Müştak Erhan
Published: November 2020

Based on some essential concepts of fractional calculus and the theorem related to the fractional extension of Lyapunov direct method, we present in this paper a synchronization scheme of fractional-order Lur’e systems. A quadratic Lyapunov function is chosen to derive the synchronization criterion. The derived criterion is a suffcient condition for the asymptotic stability of the error system, formulated in the form of linear matrix inequality (LMI). The controller gain can be achieved by solving the LMI. The proposed scheme is illustrated for fractional-order Chua’s circuits and fractional-order four-cell CNN. Numerical results, which agree well with the proposed theorem, are given to show the effectiveness of this scheme.
Carboniferous macrofloral biostratigraphy: an overview
Authors: Opluštil Stanislav , Cleal Christopher J. , Wang Jun , Wan Mingli
Published: November 2020

In the Carboniferous, terrestrial vegetation became widespread, diverse and abundant. The resulting fossil record has proved to be an effective biostratigraphic tool for intra- and interbasinal correlations. Besides palaeogeographical configurations, Carboniferous plant biostratigraphy is affected by a transition from greenhouse conditions during most of the Mississippian to an icehouse climate in the Pennsylvanian. The greenhouse Mississippian climate resulted in weak provincialism, with a cosmopolitan flora ranging from the tropics to middle latitudes. The global cooling around the Mississippian–Pennsylvanian boundary enhanced development of a latitudinal climatic zonation and related floral provincialism. These changes are expressed in the recognition of distinct realms or kingdoms, where the tropical Amerosinian Realm (or Euramerican and Cathaysian realms) is surrounded by the Angaran and Gondwanan realms occupying middle to high latitudes of the northern and southern hemispheres, respectively. Floristic endemism in the Pennsylvanian precludes development of a global macrofloral biostratigraphy. Instead, each realm or area has its own biostratigraphic scheme. Poorer and less diverse floras of the Gondwanan and Angaran realms resulted in the establishment of relatively low-resolution macrofloral biostratigraphic schemes. Higher-resolution macrofloral zonations exist only in the tropical Amerosinian Realm due to diverse and abundant floras dominated by free-sporing and early seed plants occupying extensive wetlands.
Design and fabrication of freeform holographic optical elements
Authors: Jang Changwon , Mercier Olivier , Bang Kiseung , Li Gang , Zhao Yang , Lanman Douglas
Published: November 2020

Holographic optical elements (HOEs) have a wide range of applications, including their emerging use in virtual and augmented reality displays, but their design and fabrication have remained largely limited to configurations using simple wavefronts. In this paper, we present a pipeline for the design, optimization, and fabrication of complex, customized HOEs that enhances their imaging performance and enables new applications. In particular, we propose an optimization method for grating vector fields that accounts for the unique selectivity properties of HOEs. We further show how our pipeline can be applied to two distinct HOE fabrication methods. The first uses a pair of freeform refractive elements to manufacture HOEs with high optical quality and precision. The second uses a holographic printer with two wavefront-modulating arms, enabling rapid prototyping. We propose a unified wavefront decomposition framework suitable for both fabrication approaches. To demonstrate the versatility of these methods, we fabricate and characterize a series of specialized HOEs, including an aspheric lens, a head-up display lens, a lens array, and, for the first time, a full-color caustic projection element.
A practical ply-based appearance model of woven fabrics
Authors: Montazeri Zahra , Gammelmark Søren B. , Zhao Shuang , Jensen Henrik Wann
Published: November 2020

Simulating the appearance of woven fabrics is challenging due to the complex interplay of lighting between the constituent yarns and fibers. Conventional surface-based models lack the fidelity and details for producing realistic close-up renderings. Micro-appearance models, on the other hand, can produce highly detailed renderings by depicting fabrics fiber-by-fiber, but become expensive when handling large pieces of clothing. Further, neither surface-based nor micro-appearance model has not been shown in practice to match measurements of complex anisotropic reflection and transmission simultaneously.

In this paper, we introduce a practical appearance model for woven fabrics. We model the structure of a fabric at the ply level and simulate the local appearance of fibers making up each ply. Our model accounts for both reflection and transmission of light and is capable of matching physical measurements better than prior methods including fiber based techniques. Compared to existing micro-appearance models, our model is light-weight and scales to large pieces of clothing.
MaterialGAN
Authors: Guo Yu , Smith Cameron , Hašan Miloš , Sunkavalli Kalyan , Zhao Shuang
Published: November 2020

We address the problem of reconstructing spatially-varying BRDFs from a small set of image measurements. This is a fundamentally under-constrained problem, and previous work has relied on using various regularization priors or on capturing many images to produce plausible results. In this work, we present
MaterialGAN
, a deep generative convolutional network based on StyleGAN2, trained to synthesize realistic SVBRDF parameter maps. We show that MaterialGAN can be used as a powerful material prior in an inverse rendering framework: we optimize in its latent representation to generate material maps that match the appearance of the captured images when rendered. We demonstrate this framework on the task of reconstructing SVBRDFs from images captured under flash illumination using a hand-held mobile phone. Our method succeeds in producing plausible material maps that accurately reproduce the target images, and outperforms previous state-of-the-art material capture methods in evaluations on both synthetic and real data. Furthermore, our GAN-based latent space allows for high-level semantic material editing operations such as generating material variations and material morphing.
Neural crossbreed
Authors: Park Sanghun , Seo Kwanggyoon , Noh Junyong
Published: November 2020

We propose Neural Crossbreed, a feed-forward neural network that can learn a semantic change of input images in a latent space to create the morphing effect. Because the network learns a semantic change, a sequence of meaningful intermediate images can be generated without requiring the user to specify explicit correspondences. In addition, the semantic change learning makes it possible to perform the morphing between the images that contain objects with significantly different poses or camera views. Furthermore, just as in conventional morphing techniques, our morphing network can handle shape and appearance transitions separately by disentangling the content and the style transfer for rich usability. We prepare a training dataset for morphing using a pre-trained BigGAN, which generates an intermediate image by interpolating two latent vectors at an intended morphing value. This is the first attempt to address image morphing using a pre-trained generative model in order to learn semantic transformation. The experiments show that Neural Crossbreed produces high quality morphed images, overcoming various limitations associated with conventional approaches. In addition, Neural Crossbreed can be further extended for diverse applications such as multi-image morphing, appearance transfer, and video frame interpolation.
Neural holography with camera-in-the-loop training
Authors: Peng Yifan , Choi Suyeon , Padmanaban Nitish , Wetzstein Gordon
Published: November 2020

Holographic displays promise unprecedented capabilities for direct-view displays as well as virtual and augmented reality applications. However, one of the biggest challenges for computer-generated holography (CGH) is the fundamental tradeoff between algorithm runtime and achieved image quality, which has prevented high-quality holographic image synthesis at fast speeds. Moreover, the image quality achieved by most holographic displays is low, due to the mismatch between the optical wave propagation of the display and its simulated model. Here, we develop an algorithmic CGH framework that achieves unprecedented image fidelity and real-time framerates. Our framework comprises several parts, including a novel camera-in-the-loop optimization strategy that allows us to either optimize a hologram directly or train an interpretable model of the optical wave propagation and a neural network architecture that represents the first CGH algorithm capable of generating full-color high-quality holographic images at 1080p resolution in real time.
PIE
Authors: Tewari Ayush , Elgharib Mohamed , R Mallikarjun B , Bernard Florian , Seidel Hans-Peter , Pérez Patrick , Zollhöfer Michael , Theobalt Christian
Published: November 2020

Editing of portrait images is a very popular and important research topic with a large variety of applications. For ease of use, control should be provided via a semantically meaningful parameterization that is akin to computer animation controls. The vast majority of existing techniques do not provide such intuitive and fine-grained control, or only enable coarse editing of a single isolated control parameter. Very recently, high-quality semantically controlled editing has been demonstrated, however only on synthetically created StyleGAN images. We present the first approach for embedding real portrait images in the latent space of StyleGAN, which allows for intuitive editing of the head pose, facial expression, and scene illumination in the image. Semantic editing in parameter space is achieved based on StyleRig, a pretrained neural network that maps the control space of a 3D morphable face model to the latent space of the GAN. We design a novel hierarchical non-linear optimization problem to obtain the embedding. An identity preservation energy term allows spatially coherent edits while maintaining facial integrity. Our approach runs at interactive frame rates and thus allows the user to explore the space of possible edits. We evaluate our approach on a wide set of portrait photos, compare it to the current state of the art, and validate the effectiveness of its components in an ablation study.
Neural control variates
Authors: Müller Thomas , Rousselle Fabrice , Keller Alexander , Novák Jan
Published: November 2020

We propose neural control variates (NCV) for unbiased variance reduction in parametric Monte Carlo integration. So far, the core challenge of applying the method of control variates has been finding a good approximation of the integrand that is cheap to integrate. We show that a set of neural networks can face that challenge: a normalizing flow that approximates the shape of the integrand and another neural network that infers the solution of the integral equation. We also propose to leverage a neural importance sampler to estimate the difference between the original integrand and the learned control variate. To optimize the resulting parametric estimator, we derive a theoretically optimal, variance-minimizing loss function, and propose an alternative, composite loss for stable online training in practice. When applied to light transport simulation, neural control variates are capable of matching the state-of-the-art performance of other unbiased approaches, while providing means to develop more performant, practical solutions. Specifically, we show that the learned light-field approximation is of sufficient quality for high-order bounces, allowing us to omit the error correction and thereby dramatically reduce the noise at the cost of negligible visible bias.
Egocentric videoconferencing
Authors: Elgharib Mohamed , Mendiratta Mohit , Thies Justus , Niessner Matthias , Seidel Hans-Peter , Tewari Ayush , Golyanik Vladislav , Theobalt Christian
Published: November 2020

We introduce a method for egocentric videoconferencing that enables hands-free video calls, for instance by people wearing smart glasses or other mixed-reality devices. Videoconferencing portrays valuable non-verbal communication and face expression cues, but usually requires a front-facing camera. Using a frontal camera in a hands-free setting when a person is on the move is impractical. Even holding a mobile phone camera in the front of the face while sitting for a long duration is not convenient. To overcome these issues, we propose a low-cost wearable egocentric camera setup that can be integrated into smart glasses. Our goal is to mimic a classical video call, and therefore, we transform the egocentric perspective of this camera into a front facing video. To this end, we employ a conditional generative adversarial neural network that learns a transition from the highly distorted egocentric views to frontal views common in videoconferencing. Our approach learns to transfer expression details directly from the egocentric view without using a complex intermediate parametric expressions model, as it is used by related face reenactment methods. We successfully handle subtle expressions, not easily captured by parametric blendshape-based solutions, e.g., tongue movement, eye movements, eye blinking, strong expressions and depth varying movements. To get control over the rigid head movements in the target view, we condition the generator on synthetic renderings of a moving neutral face. This allows us to synthesis results at different head poses. Our technique produces temporally smooth video-realistic renderings in real-time using a video-to-video translation network in conjunction with a temporal discriminator. We demonstrate the improved capabilities of our technique by comparing against related state-of-the art approaches.
Differentiable refraction-tracing for mesh reconstruction of transparent objects
Authors: Lyu Jiahui , Wu Bojian , Lischinski Dani , Cohen-Or Daniel , Huang Hui
Published: November 2020

Capturing the 3D geometry of transparent objects is a challenging task, ill-suited for general-purpose scanning and reconstruction techniques, since these cannot handle specular light transport phenomena. Existing state-of-the-art methods, designed specifically for this task, either involve a complex setup to reconstruct complete refractive ray paths, or leverage a data-driven approach based on synthetic training data. In either case, the reconstructed 3D models suffer from over-smoothing and loss of fine detail. This paper introduces a novel, high precision, 3D acquisition and reconstruction method for solid transparent objects. Using a static background with a coded pattern, we establish a mapping between the camera view rays and locations on the background. Differentiable tracing of refractive ray paths is then used to directly optimize a 3D mesh approximation of the object, while simultaneously ensuring silhouette consistency and smoothness. Extensive experiments and comparisons demonstrate the superior accuracy of our method.
To cut or to fill
Authors: Zeng Dan , Chambers Erin , Letscher David , Ju Tao
Published: November 2020

We present a novel algorithm for simplifying the topology of a 3D shape, which is characterized by the number of connected components, handles, and cavities. Existing methods either limit their modifications to be only cutting or only filling, or take a heuristic approach to decide where to cut or fill. We consider the problem of finding a globally optimal set of cuts and fills that achieve the simplest topology while minimizing geometric changes. We show that the problem can be formulated as graph labelling, and we solve it by a transformation to the Node-Weighted Steiner Tree problem. When tested on examples with varying levels of topological complexity, the algorithm shows notable improvement over existing simplification methods in both topological simplicity and geometric distortions.
Mechanism of Coal Bursts Induced by Horizontal Section Mining of Steeply Inclined Coal Seams and Application of Microseismic Multiparameter Monitoring in Early Warning
Authors: Wang Sheng-Chuan , Dou Lin-Ming , Wang Zheng-Yi , Bai Jin-Zheng , Chai Yan-Jiang
Published: November 2020

Coal bursts occurring in steeply inclined coal seams (SICSs) are increasingly severe. To solve this problem, a mechanical model for the distribution of static stress on coal‐rock masses along panels and the distribution of dynamic load induced by the breakage of thick and hard roofs with propagation distance was established. The stress characteristics after a superposition of dynamic and static loads on the roof and floor roadways (Rr and Rf) were determined. In addition, precursory information characteristics and index sensitivities of four indices for dynamic loads and the CT index for static loads based on seismic tomography were separately analyzed. The monitoring and warning indices for SICSs and flat seams were compared. The results showed that the static stress of Rr was significantly higher than that of Rf, which provided a basis for the stress‐triggering coal burst behaviors. Three indices for dynamic loads and seismic tomography results exhibited remarkable precursory information and high sensitivity. However, the performance of lack of shock index is poor. The continuous anomaly and the contradiction of indices at Rr and Rf can be considered as precursory information for predicting coal bursts.
Multiperspective Bus Route Planning in a Stackelberg Game Framework
Authors: Liu Xinyu , Yu Jie , Yang Xiaoguang , Tan Weijie
Published: November 2020

Bus route planning is a challenging task due to multiple perspective interactions among passengers, service providers, and government agencies. This paper presents a multidimensional Stackelberg-game-based framework and mathematical model to best trade off the decisions of multiple stakeholders that previous literature rarely captures, i.e., governments, service providers, and passengers, in planning a new bus route or adjusting an existing one. The proposed model features a bilevel structure with the upper level reflecting the perspective of government agencies in subsidy allocation and the lower level representing the decisions of service providers in dispatching frequency and bus fleet size design. The bilevel model is framed as a Stackelberg game where government agencies take the role of “leader” and service providers take the role of “follower” with social costs and profits set as payoffs, respectively. This Stackelberg-game-based framework can reflect the decision sequence of both participants as well as their competition or collaboration relationship in planning a bus route. The impact of such decisions on the mode and route choices of passengers is captured by a Nested Logit model. A partition-based bisection algorithm is developed to solve the proposed model. Results from a case study in Shanghai validate the effectiveness and performance of the proposed model and algorithm.
Hybrid Structures Applied to Ideals in BCI-Algebras
Authors: Muhiuddin G. , Al-Kadi D. , Mahboob A.
Published: November 2020

In this paper, the notion of hybrid structure is applied to the ideal theory in BCI-algebras. In fact, we introduce the notions of hybridp-ideal, hybrid h-ideal, and hybrid a-ideal in BCI-algebras and investigate their related properties. Furthermore, we show that every hybridp-ideal (or h-ideal or a-ideal) is a hybrid ideal in a BCI-algebra but converse need not be true in general and in support, and we exhibit counter examples for each case. Moreover, we consider characterizations of hybridp-ideal, hybrid h-ideal, and hybrid a-ideal in BCI-algebras.
Constraints on Neutrino Electric Millicharge from Experiments of Elastic Neutrino-Electron Interaction and Future Experimental Proposals Involving Coherent Elastic Neutrino-Nucleus Scattering
Authors: Parada A.
Published: November 2020

In several extensions of the Standard Model of Particle Physics (SMPP), the neutrinos acquire electromagnetic properties such as the electric millicharge. Theoretical and experimental bounds have been reported in the literature for this parameter. In this work, we first carried out a statistical analysis by using data from reactor neutrino experiments, which include elastic neutrino-electron scattering (ENES) processes, in order to obtain both individual and combined limits on the neutrino electric millicharge (NEM). Then, we performed a similar calculation to show an estimate of the sensitivity of future experiments of reactor neutrinos to the NEM, by involving coherent elastic neutrino-nucleus scattering (CENNS). In the first case, the constraints achieved from the combination of several experiments are

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(90% C.L.), and in the second scenario, we obtained the bounds

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(90% C.L.). As we will show here, these combined analyses of different experimental data can lead to stronger constraints than those based on individual analysis, where CENNS interactions would stand out as an important alternative to improve the current limits on NEM.