bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetic models for epidemic dynamics with social heterogeneity
Authors: Dimarco G. , Perthame B. , Toscani G. , Zanella M.
Published: June 2021

We introduce a mathematical description of the impact of the number of daily contacts in the spread of infectious diseases by integrating an epidemiological dynamics with a kinetic modeling of population-based contacts. The kinetic description leads to study the evolution over time of Boltzmann-type equations describing the number densities of social contacts of susceptible, infected and recovered individuals, whose proportions are driven by a classical SIR-type compartmental model in epidemiology. Explicit calculations show that the spread of the disease is closely related to moments of the contact distribution. Furthermore, the kinetic model allows to clarify how a selective control can be assumed to achieve a minimal lockdown strategy by only reducing individuals undergoing a very large number of daily contacts. We conduct numerical simulations which confirm the ability of the model to describe different phenomena characteristic of the rapid spread of an epidemic. Motivated by the COVID-19 pandemic, a last part is dedicated to fit numerical solutions of the proposed model with infection data coming from different European countries.
Retinal nerve fibre layer thickness measurements in childhood glaucoma: the role of scanning laser polarimetry and optical coherence tomography
Authors: Lever Mael , Halfwassen Christian , Unterlauft Jan Darius , Bechrakis Nikolaos E. , Manthey Anke , Böhm Michael R. R.
Published: June 2021

Purpose

A central diagnostic tool in adult glaucoma is the peripapillary retinal nerve fibre layer (pRNFL) thickness. It can be assessed by scanning laser polarimetry (SLP) or optical coherence tomography (OCT). However, studies investigating the relevance of pRNFL measurements in children are rare. This study aims to compare the glaucoma diagnosing ability of SLP and OCT pRNFL thickness measurements in a paediatric population.

Methods

This retrospective study included 105 children (glaucoma: 22 (21.0%); healthy glaucoma suspects: 83 (79.0%)) aged 4–18 years, examined with SLP (GDxPro/ECC, Carl Zeiss Meditec) and spectral-domain OCT (SPECTRALIS®, Heidelberg Engineering). The thickness of pRNFL sectors was compared between diseased and healthy participants. Areas under the receiver-operating characteristic curves (AUC) and logistic regression results were used to compare the glaucoma discriminative capacity between SLP and OCT measurements.

Results

Using OCT, pRNFL thickness was decreased in the superior, nasal, and inferior quadrants of glaucoma patients compared to healthy controls (P < 0.001, each). With SLP, such a difference was only observed in the inferior quadrant (P = 0.011). A correlation between glaucoma diagnosis and OCT-measured pRNFL thickness was found in all quadrants (P < 0.001) other than the temporal. With SLP, a correlation was found for the total average thickness (P = 0.037) and inferior quadrant (P = 0.0019). Finally, the AUCs of OCT measurements were markedly higher than those of SLP (e.g., inferior quadrant: OCT 0.83, SLP 0.68).

Conclusion

pRNFL thickness measurements using both OCT and SLP, correlate notably with the presence of glaucoma. In general, the diagnostic performance of pRNFL thickness measurements seems higher for OCT than for SLP. Thus, pRNFL thickness measurements could provide important information, complementing conventional clinical and functional parameters in the diagnostic process of paediatric glaucoma.
Evolution and diversity of the angiosperm anther: trends in function and development
Authors: Åstrand Johanna , Knight Christopher , Robson Jordan , Talle Behzad , Wilson Zoe A.
Published: June 2021

Key message

Anther development and dehiscence is considered from an evolutionary perspective to identify drivers for differentiation, functional conservation and to identify key questions for future male reproduction research.

Development of viable pollen and its timely release from the anther are essential for fertilisation of angiosperm flowers. The formation and subsequent dehiscence of the anther are under tight regulatory control, and these processes are remarkably conserved throughout the diverse families of the angiosperm clade. Anther development is a complex process, which requires timely formation and communication between the multiple somatic anther cell layers (the epidermis, endothecium, middle layer and tapetum) and the developing pollen. These layers go through regulated development and selective degeneration to facilitate the formation and ultimate release of the pollen grains. Insight into the evolution and divergence of anther development and dehiscence, especially between monocots and dicots, is driving greater understanding of the male reproductive process and increased, resilient crop yields. This review focuses on anther structure from an evolutionary perspective by highlighting their diversity across plant species. We summarise new findings that illustrate the complexities of anther development and evaluate how they challenge established models of anther form and function, and how they may help to deliver future sustainable crop yields.
Mathematical modeling of physically nonlinear 3D beams and plates made of multimodulus materials
Authors: Krysko A. V. , Awrejcewicz J. , Bodyagina K. S. , Zhigalov M. V. , Krysko V. A.
Published: June 2021

In this work, mathematical models of physically nonlinear plates and beams made from multimodulus materials are constructed. Our considerations are based on the 3D deformation theory of plasticity, the von Mises plasticity criterion and the method of variable parameters of the theory of elasticity developed by Birger. The proposed theory and computational algorithm enable for solving problems of three types of boundary conditions, edge conditions and arbitrary lateral load distribution. The problem is solved by the finite element method (FEM), and its convergence and the reliability of the results are investigated. Based on numerical experiments, the influence of multimodulus characteristics of the material of the beam and the plate on their stress–strain states under the action of transverse loads is illustrated and discussed.
Selected clinical parameters and changes in cardiac morphology and function assessed by magnetic resonance imaging in patients with rheumatoid arthritis and ankylosing spondylitis without clinically apparent heart disease
Authors: Tański Wojciech , Gać Paweł , Chachaj Angelika , Sobieszczańska Małgorzata , Poręba Rafał , Szuba Andrzej
Published: June 2021

Background

The aim of the study was to assess the relationship between the occurrence of rheumatoid arthritis (RA) and ankylosing spondylitis (AS) and the cardiac magnetic resonance (CMR) changes in people without clinically overt heart disease.

Methods

The study group consisted of 74 people (48.81 ± 11.35 years): 29 patients with RA, 23 patients with AS and 22 people from control group. Blood samples were taken to assess laboratory parameters, disease activity was determined using activity scales, and CMR was performed.

Results

It was shown that the factors independently related to higher left ventricular mass index are AS occurrence, human B27 leukocyte antigen occurrence, higher neutrophil gelatinase–associated lipocalin concentration (NGAL) and higher body mass index (BMI). The lower right ventricular ejection fraction is result of an independent effect of RA, AS and higher NGAL. RA presence, methotrexate use, higher rheumatoid factor titer, higher NGAL, older age and higher BMI should be considered independent risk factors for greater left ventricular myocardium water content. RA occurrence, AS occurrence, type 2 diabetes occurrence and a higher C-reactive protein concentration can be independently associated with a higher probability of non-ischemic left ventricular myocardium injury. Larger pericardial fluid volume is result of an independent effect of higher NGAL, higher anti-cyclic citrullinated peptide antibodies titer and higher DAS28 disease activity index. Use of steroids is protective factor against larger volume of pericardial fluid.

Conclusions

RA and AS in people without clinically apparent heart disease are associated with the occurrence of adverse changes in CMR.

Key Points•RA and AS in people without clinically apparent heart disease are associated with the occurrence of adverse changes in CMR..•The independent risk factors for higher LVEF are AS occurrence, human B27 leukocyte antigen occurrence, higher NGAL concentration and higher BMI..•RA presence, methotrexate use, higher RF, higher NGAL, older age and higher BMI are independent risk factors for higher LV T2 ratio..•RA occurrence, AS occurrence, type 2 diabetes occurrence and a higher CRP are independently associated with a higher risk of non-ischemic LV myocardium injury..
Clothoid fitting and geometric Hermite subdivision
Authors: Reif Ulrich , Weinmann Andreas
Published: June 2021

We consider geometric Hermite subdivision for planar curves, i.e., iteratively refining an input polygon with additional tangent or normal vector information sitting in the vertices. The building block for the (nonlinear) subdivision schemes we propose is based on clothoidal averaging, i.e., averaging w.r.t. locally interpolating clothoids, which are curves of linear curvature. To this end, we derive a new strategy to approximate Hermite interpolating clothoids. We employ the proposed approach to define the geometric Hermite analogues of the well-known Lane-Riesenfeld and four-point schemes. We present numerical results produced by the proposed schemes and discuss their features.
Activity coefficient models for accurate prediction of adsorption azeotropes
Authors: Luberti Mauro , Mennitto Roberto , Brandani Stefano , Santori Giulio , Sarkisov Lev
Published: June 2021

In this study seven adsorption azeotropes involving binary systems and zeolite-based adsorbents were systematically investigated. Pure component isotherms and mixed-gas adsorption data were taken from published literature except for the benzene–propene system on silicalite, which is newly presented in this work using molecular simulations. Experimental adsorbed phase composition and total amount adsorbed of the azeotropic systems were compared with the predictions of several models including: the ideal adsorbed solution theory (IAST), the heterogeneous ideal adsorbed solution theory (HIAST) and the real adsorbed solution theory (RAST) coupled with the 1-parameter Margules (1-Margules) and the van Laar equations. In the latter two models an additional loading parameter was incorporated in the expression of the excess Gibbs energy to account for the reduced grand potential dependency of the activity coefficients in the adsorbed phase. It was found that the HIAST and RAST–1-Margules models were able to predict the azeotropic behaviour of some systems with good accuracy. However, only the RAST–van Laar model consistently showed an average relative deviation below 3% compared to experimental data for both the adsorbed phase composition and the total amount adsorbed across the systems. This modified van Laar equation is therefore preferable in those engineering applications when the location of adsorption azeotropes is required with great accuracy and when there is lack of detailed characterization of the adsorbent that is needed to carry out molecular simulations.
The size-dependent elastohydrodynamic lubrication contact of a coated half-plane with non-Newtonian fluid
Authors: Su Jie , Song Hongxia , Ke Liaoliang , Aizikovich S. M.
Published: June 2021

Based on the couple-stress theory, the elastohydrodynamic lubrication (EHL) contact is analyzed with a consideration of the size effect. The lubricant between the contact surface of a homogeneous coated half-plane and a rigid punch is supposed to be the non-Newtonian fluid. The density and viscosity of the lubricant are dependent on fluid pressure. Distributions of film thickness, in-plane stress, and fluid pressure are calculated by solving the nonlinear fluid-solid coupled equations with an iterative method. The effects of the punch radius, size parameter, coating thickness, slide/roll ratio, entraining velocity, resultant normal load, and stiffness ratio on lubricant film thickness, in-plane stress, and fluid pressure are investigated. The results demonstrate that fluid pressure and film thickness are obviously dependent on the size parameter, stiffness ratio, and coating thickness.
An adaptive parallel algorithm for finite language decomposition
Authors: Jastrzęb Tomasz , Czech Zbigniew J. , Wieczorek Wojciech
Published: June 2021

The computationally hard problem of finite language decomposition is investigated. A finite language L is decomposable if there are two languages L1 and L2 such that L = L1L2. Otherwise, L is prime. The main contribution of the paper is an adaptive parallel algorithm for finding all decompositions L1L2 of L. The algorithm is based on an exhaustive search and incorporates several original methods for pruning the search space. Moreover, the algorithm is adaptive since it changes its behavior based on the runtime acquired data related to its performance. Comprehensive computational experiments on more than 4000 benchmark languages generated over alphabets of various sizes have been carried out. The experiments showed that by using the power of parallel computing the decompositions of languages containing more than 200000 words can be found. Decompositions of languages of that size have not been reported in the literature so far.
The association of socioeconomic status on treatment strategy in patients with stage I and II breast cancer in the Netherlands
Authors: Filipe M. D. , Siesling S. , Vriens M. R. , van Diest P. , Witkamp A. J.
Published: June 2021

Background

Previous studies have shown that socioeconomic status (SES) influences breast cancer therapy. However, these studies were performed in countries with unequal access to healthcare. Therefore, the aim of this study is to investigate whether SES also contributes to the likelihood of receiving a certain therapy in the Netherlands, a country with supposedly equal access to healthcare.

Materials and methods

From the Netherlands Cancer Registry, 105,287 patients with newly diagnosed stage I or II breast cancer diagnosed between 2011 and 2018 were selected for analysis. SES was calculated from the average incomes of each postal code, which were divided into 10 deciles. Primary outcome was the effect of SES on the likelihood of undergoing surgery and secondary outcome was the effect of SES on the likelihood of the type of surgery. Both outcomes were corrected for patient, tumor, and hospital characteristics and were expressed as odds ratio (OR) with 95% confidence interval (CI).

Results

SES did not affect the likelihood of a breast cancer patient to undergo surgery (OR 1.00 per 10% stratum). In contrast, increased age and higher tumor stage were the most important factors determining whether patients underwent surgery.

Patients with higher SES were less likely to undergo mastectomy (OR 0.98). Additionally, more recently diagnosed patients were less likely to undergo mastectomy (OR 0.93 per year) while patients with higher tumor stage were more likely to undergo mastectomy (OR 3.42).

Conclusion

SES does not affect whether a patient undergoes surgery; however, higher SES increased the likelihood of BCT.
Psychological Symptoms in Italian, Spanish and Portuguese Youth During the COVID-19 Health Crisis: A Longitudinal Study
Authors: Orgilés Mireia , Francisco Rita , Delvecchio Elisa , Espada José P. , Mazzeschi Claudia , Pedro Marta , Morales Alexandra
Published: June 2021

Aiming to slow down the spread of the COVID-19, a lockdown was declared in the first term of 2020 in many European countries, applying different restrictions measures. Although the psychological effects of home confinement in children have been described, there is a lack of longitudinal research examining the impact of the confinement over time. The present study analyzes the evolution of the psychological wellbeing of children and adolescents from three European countries with different restrictions. Parents of 624 Italian, Spanish, and Portuguese children and adolescents aged 3 to 18 years old completed the “Impact Scale of COVID-19 and Home Confinement on Children and Adolescents” two, five, and eight weeks after the lockdown. Results show a different pattern for each country. Children from Italy, the first European country that applied a lockdown, were better adapted than Spanish and Portuguese children the first two weeks after confinement but they were more psychologically impacted by home confinement at the eight-week assessment. Portuguese children, who followed a general duty of home confinement, were the best adapted to the situation, with no significant differences over time. A significant change was found in anxiety symptoms in Spanish children, with a decrease at the last assessment. Findings suggest that long confinements and hard restrictions affect children, so prevention measures should be applied during confinements to prevent psychological problems in children.
Individual differences limit predicting well-being and productivity using software repositories: a longitudinal industrial study
Authors: Kuutila Miikka , Mäntylä Mika , Claes Maëlick , Elovainio Marko , Adams Bram
Published: June 2021

Reports of poor work well-being and fluctuating productivity in software engineering have been reported in both academic and popular sources. Understanding and predicting these issues through repository analysis might help manage software developers’ well-being. Our objective is to link data from software repositories, that is commit activity, communication, expressed sentiments, and job events, with measures of well-being obtained with a daily experience sampling questionnaire. To achieve our objective, we studied a single software project team for eight months in the software industry. Additionally, we performed semi-structured interviews to explain our results. The acquired quantitative data are analyzed with generalized linear mixed-effects models with autocorrelation structure. We find that individual variance accounts for most of the R2 values in models predicting developers’ experienced well-being and productivity. In other words, using software repository variables to predict developers’ well-being or productivity is challenging due to individual differences. Prediction models developed for each developer individually work better, with fixed effects R2 value of up to 0.24. The semi-structured interviews give insights into the well-being of software developers and the benefits of chat interaction. Our study suggests that individualized prediction models are needed for well-being and productivity prediction in software development.
Responsible AI for Digital Health: a Synthesis and a Research Agenda
Authors: Trocin Cristina , Mikalef Patrick , Papamitsiou Zacharoula , Conboy Kieran
Published: June 2021

Responsible AI is concerned with the design, implementation and use of ethical, transparent, and accountable AI technology in order to reduce biases, promote fairness, equality, and to help facilitate interpretability and explainability of outcomes, which are particularly pertinent in a healthcare context. However, the extant literature on health AI reveals significant issues regarding each of the areas of responsible AI, posing moral and ethical consequences. This is particularly concerning in a health context where lives are at stake and where there are significant sensitivities that are not as pertinent in other domains outside of health. This calls for a comprehensive analysis of health AI using responsible AI concepts as a structural lens. A systematic literature review supported our data collection and sampling procedure, the corresponding analysis, and extraction of research themes helped us provide an evidence-based foundation. We contribute with a systematic description and explanation of the intellectual structure of Responsible AI in digital health and develop an agenda for future research.
Practical identifiability of electrochemical P2D models for lithium-ion batteries
Authors: Laue Vincent , Röder Fridolin , Krewer Ulrike
Published: June 2021

Electrochemical models play a significant role in today’s rapid development and enhancement of lithium-ion batteries. For instance, they are applied for design and process optimization. More recently, model and parameter identifiability are gaining interest as thorough model parameterization is key to reliable simulation results. Especially electrochemical models are often prone to unidentifiability and overfitting due to their high number of adjustable parameters. In this article, the most common electrochemical peudo-2D model of a lithium-ion battery is parameterized. A three-step procedure is applied which considers quasi-static 3-electrode measurements of the open-circuit potential, C-rate tests, and electrochemical impedance spectra. Identifiability of each step is discussed in-depth and a general guidance for future parameterizations is derived. The conducted study reveals the insufficiency of open-circuit potential and C-rate tests to fully parameterize the electrochemical model. Highly dynamic tests, e.g., impedance spectroscopy, are required to resolve the ambiguity of diffusive and electric processes under quasi-static conditions. Any parameterization of electrochemical models requires experimental data of electrode-resolved tests, as well as a combination of quasi-static and highly dynamic tests. The results of this study provide guidance for the use of electrochemical models in applied sciences and industry.

Graphic abstract
General nucleation-growth type kinetic models of nanoparticle formation: possibilities of finding analytical solutions
Authors: Szabó Rebeka , Lente Gábor
Published: June 2021

In this work, analytical solutions for the time dependences for the concentration of each chemical species are determined in a class of nucleation-growth type kinetic models of nanoparticle formation. These models have an infinitely large number of dependent variables and describe the studied process without approximations. Symbolic solutions are found for the mass kernel (where reactivity is directly proportional to the mass of a nanoparticle) and the diffusion kernel (where reactivity is independent of the size of the nanoparticle). The results show that the average particle size is primarily determined by the type of the kernel function and the ratio of the rate constants of spontaneous nucleation and particle growth. The final distribution of nanoparticle sizes is a continuously decreasing function in each studied case. Furthermore, the time dependences of the concentrations of monomeric units show the induction behavior that has already been observed in many experimental studies.
Solving Mixed Variational Inequalities Beyond Convexity
Authors: Grad Sorin-Mihai , Lara Felipe
Published: June 2021

We show that Malitsky’s recent Golden Ratio Algorithm for solving convex mixed variational inequalities can be employed in a certain nonconvex framework as well, making it probably the first iterative method in the literature for solving generalized convex mixed variational inequalities, and illustrate this result by numerical experiments.
Agroecology landscapes
Authors: Jeanneret Ph. , Aviron S. , Alignier A. , Lavigne C. , Helfenstein J. , Herzog F. , Kay S. , Petit S.
Published: June 2021

Context

Agroecology combines agronomic and ecological concepts. It relies on the enhancement of biodiversity and related ecosystem services to support agricultural production. It is dependent on biological interactions for the design and management of agricultural systems in agricultural landscapes.

Objectives

We review the role of landscape ecology to understand and promote biodiversity, pest regulation and crop pollination for the designing of “agroecology landscapes”. We illustrate the use of landscape ecological methods for supporting agroforestry systems as an example of agroecological development, and we propose pathways to implement agroecology at landscape scale.

Methods

The state of the art of how landscape ecology contributes to agroecology development is summarized based on a literature review.

Results

Agroecology requires thinking beyond the field scale to consider the positioning, quality and connectivity of fields and semi-natural habitats at larger spatial scales. The spatial and temporal organisation of semi-natural elements and the crop mosaic interact. Understanding this interaction is the pre-requisite for promoting patterns and mechanisms that foster biodiversity and ecosystem service provision. Promoting agroecological practices beyond individual farm borders can be rooted in a bottom-up approach from agroecological lighthouse farms to farm networks to amplify agroecology adoption at the landscape scale.

Conclusions

Achieving agricultural landscapes composed of fields and farms following agroecological management requires understanding of biodiversity patterns, biological interactions and mechanisms that determine and boost ecosystem functioning to improve services at landscape scale, involving farmers in a bottom-up and context-specific approach.
Orangutan movement and population dynamics across human-modified landscapes: implications of policy and management
Authors: Seaman Dave J. I. , Voigt Maria , Bocedi Greta , Travis Justin M. J. , Palmer Stephen C. F. , Ancrenaz Marc , Wich Serge , Meijaard Erik , Bernard Henry , Deere Nicolas J. , Humle Tatyana , Struebig Matthew J.
Published: June 2021

Context

Agricultural expansion is a leading cause of deforestation and habitat fragmentation globally. Policies that support biodiversity and facilitate species movement across farmland are therefore central to sustainability efforts and wildlife conservation in these human-modified landscapes.

Objectives

We investigated the conservation impact of several potential management scenarios on animal populations and movement in a human-modified tropical landscape, focusing on the critically endangered Bornean orangutan,Pongo pygmaeus.

Methods

We used an individual-based modelling platform to simulate population dynamics and movements across four possible landscape management scenarios for a highly modified oil palm-dominated landscape in Sabah, Malaysian Borneo.

Results

Scenarios that maximised the retention of natural forest remnants in agricultural areas through sustainability certification standards supported stable orangutan populations. These populations were up to 45% larger than those supported under development-focused scenarios, where forest retention was not prioritised. The forest remnants served as corridors or stepping-stones, increasing annual emigration rates across the landscape, and reducing orangutan mortality by up to 11%. Sensitivity analyses demonstrated that this outcome was highly contingent on minimising mortality during dispersal.

Conclusions

Management that promotes maximising natural forest cover through certification, such as that promoted by the Roundtable on Sustainable Palm Oil, can maintain viable orangutan populations over the lifespan of an oil palm plantation and facilitate movement among otherwise isolated populations. However, minimising hunting and negative human–orangutan interactions, while promoting peaceful co-existence between apes and people, will be imperative to insure positive conservation outcomes.
Robust optimization of stiff delayed systems: application to a fluid catalytic cracking unit
Authors: Otten-Weinschenker Jonas , Mönnigmann Martin
Published: June 2021

We apply a robust steady state optimization method for stiff delay differential equations to the economic optimization of a fluidized catalytic cracking unit. Stiff systems of differential equations appear in this case due to the different time scales in the gas and fluid phase. Delays result from the catalyst hold-ups in the standpipes connecting riser and regenerator. We show that the proposed robust optimization method can cope with stiffness and delays. Moreover, the proposed method is capable of simultaneously optimizing the process parameters and tuning controller parameters.
Anastrozole as add-on therapy for cabergoline-resistant prolactin-secreting pituitary adenomas: real-life experience in male patients
Authors: Ceccato Filippo , Lizzul Laura , Voltan Giacomo , Barbot Mattia , Scaroni Carla
Published: June 2021

Introduction

Prolactin-secreting adenoma (PRLoma) can present as large and invasive neoplasm, with increased markers of cellular proliferation. First-line approach is Dopamine Agonists (DAs) treatment; however, DA-resistance has been reported, especially in male patients. Estrogens induce lactotroph cell replication and PRL secretion: the use of anti-estrogen treatment in patients with PRLoma have been described in few cases. We reported our experience regarding treatment with the aromatase inhibitor anastrozole (ANA) as add-on therapy for male patients with DA resistant PRLoma.

Materials and methods

We describe four male patients (26, 38, 29 and 19 years old at diagnosis), with PRLoma (median diameter 26 mm, PRL 7730 μg/L). They were resistant to cabergoline (CAB, > 2 mg/week) in terms of PRL secretion and tumor size reduction. ANA 1 mg/day was added to the maximum tolerated dose of CAB for at least 1 year. Magnetic Resonance was performed at baseline, after 6 months of CAB + ANA combination and every 12 months afterward.

Results

PRL levels decreased in all patients after CAB + ANA (mean − 70%, range − 44/− 97%), achieving a normalization of PRL levels in one case. Tumor size decreased in all cases (mean − 47%, range − 24.5/− 68%). No severe adverse effects have been reported, a moderate weight gain has been observed in two cases.

Conclusions

Addition of an aromatase inhibitor (ANA) to the dopamine agonist therapy improved the control of prolactin levels and induced tumour regression.
Sea lice (Copepoda: Caligidae) from South Africa, with descriptions of two new species of Caligus
Authors: Hayes Polly M. , Christison Kevin W. , Vaughan David B. , Smit Nico J. , Boxshall Geoffrey A.
Published: June 2021

Thirteen species of sea lice (family Caligidae) are reported from a range of elasmobranch and actinopterygian fishes caught off South Africa or obtained from public aquaria in South Africa. Two new species of Caligus Müller, 1785 are described: C. linearisn. sp. from Pomatomus saltatrix (Linnaeus) and C. tumulusn. sp. from Chrysoblephus cristiceps (Valenciennes). A supplementary description is provided for both sexes of Caligus tetrodontis Barnard, 1948 taken from Amblyrhynchotes honckenii (Bloch) and previous records of this parasite from South African fishes are critically reviewed. It is concluded that Caligus material from Arothron hispidus Linnaeus was previously misidentified as C. tetrodontis and is in urgent need of re-examination. Morphological and molecular observations on Caligus furcisetifer Redkar, Rangnekar & Murti, 1949 indicate that this copepod is phenotypically and genetically identical to Lepeophtheirus natalensis Kensley & Grindley, 1973, and the latter becomes a junior subjective synonym of C. furcisetifer. We include new geographical distribution records for Caligus longipedis Bassett-Smith, 1898, C. rufimaculatus Wilson, 1905 and Lepeophtheirus spinifer Kirtisinghe, 1937, extending into South African waters, as well as both new distribution and host records for Alebion gracilis Wilson, 1905, Caligus dakari van Beneden, 1892 and Lepeophtheirus acutus Heegaard, 1943. The molecular analysis confirmed the monophyly of the genus Caligus. The South African species of Caligus did not cluster together, but the two included South African species of Lepeophtheirus were recovered as sister taxa.
Atmospheric deposition of chlorinated and brominated polycyclic aromatic hydrocarbons in central Europe analyzed by GC-MS/MS
Authors: Jin Rong , Bandowe Benjamin A. Musa , Zheng Minghui , Liu Guorui , Nežiková Barbora , Prokeš Roman , Čupr Pavel , Klánová Jana , Lammel Gerhard
Published: June 2021

Chlorinated and brominated polycyclic aromatic hydrocarbons (ClPAHs and BrPAHs) are persistent organic pollutants that are ubiquitous in the atmospheric environment. The sources, fate, and sinks in the atmosphere of these substances are largely unknown. One of the reasons is the lack of widely accessible analytical instrumentation. In this study, a new analytical method for ClPAHs and BrPAHs using gas-chromatography coupled with triple quadrupole mass spectrometry is presented. The method was applied to determine ClPAHs and BrPAHs in total deposition samples collected at two sites in central Europe. Deposition fluxes of ClPAHs and BrPAHs ranged 580 (272–962) and 494 (161–936) pg m−2 day−1, respectively, at a regional background site, Košetice, and 547 (351–724) and 449 (202–758) pg m−2 day−1, respectively, at a semi-urban site, Praha-Libuš. These fluxes are similar to those of PCBs and more than 2 orders of magnitude lower than those of the parent PAHs in the region. Seasonal variations of the deposition fluxes of these halogenated PAHs were found with maxima in summer and autumn, and minima in winter at Košetice, but vice versa at Praha-Libuš. The distribution of ClPAHs and BrPAHs between the particulate and dissolved phases in deposition samples suggests higher degradability of particulate BrFlt/Pyr and BrBaA than of the corresponding ClPAHs. A number of congeners were detected for the first time in the atmospheric environment.
Lung cancer screening by single-shot dual-energy subtraction using flat-panel detector
Authors: Mogami Hiroshi , Onoike Yumiko , Miyano Hiroshi , Arakawa Kenji , Inoue Hiromi , Sakae Kouji , Kawakami Toshiaki
Published: June 2021

Purpose

The purpose of this study was to evaluate the usefulness of single-shot dual-energy subtraction (DES) method using a flat-panel detector for lung cancer screening

Materials and methods

The subjects were 13,315 residents (5801 males and 7514 females) aged 50 years or older (50–97 years, with an intermediate value of 68 years) who underwent lung cancer screening for a period of 1 year and 6 months from January 2019 to June 2020. We investigated whether the number of lung cancers detected, the detection rate, and the rate of required scrutiny changed, when DES images were added to the judgment based on conventional chest radiography.

Results

When DES images were added, the number and percentage of cancer detection increased from 16 (0.12%) to 23 (0.17%) (P < 0.05). Five of the newly detected 7 lung cancers were in the early stages of resectable cancer. The rate of participants requiring scrutiny increased slightly from 1.1 to 1.3%.

Conclusion

DES method improved the detection of lung cancer in screening. The increase in the percentage of participants requiring scrutiny was negligible.
Bioactive adrenomedullin a prognostic biomarker in patients with mild to moderate dyspnea at the emergency department: an observational study
Authors: Bronton Kevin , Wessman Torgny , Gränsbo Klas , Schulte Janin , Hartmann Oliver , Melander Olle
Published: June 2021

Acute dyspnea with underlying congestion is a leading cause of emergency department (ED) visits with high rates of hospitalization. Adrenomedullin is a vasoactive neuropeptide hormone secreted by the endothelium that mediates vasodilation and maintains vascular integrity. Plasma levels of biologically active adrenomedullin (bio-ADM) predict septic shock and vasopressor need in critically ill patients and are associated with congestion in patients with acute heart failure (HF) but the prognostic value in unselected dyspneic patients at the ED is unknown. The purpose of this study is to test if bio-ADM predicts adverse outcomes when sampled in patients with acute dyspnea at presentation to the ED. In this single-center prospective observational study, we included 1402 patients from the ADYS (Acute DYSpnea at the Emergency Department) cohort in Malmö, Sweden. We fitted logistic regression models adjusted for sex, age, N-terminal pro-B-type natriuretic peptide (NT-proBNP), creatinine, and C-reactive protein (CRP) to associate bio-ADM plasma levels to mortality, hospitalization, intravenous (IV) diuretic treatment and HF diagnosis. Using receiver operating characteristic (ROC) curve analysis we evaluated bio-ADM discrimination for these outcomes compared to a reference model (sex, age, NT-proBNP, creatinine, and CRP). Model performance was compared by performing a likelihood ratio test on the deviances of the models. Bio-ADM (per interquartile range from median) predicts both 90-day mortality [odds ratio (OR): 1.5, 95% confidence interval (CI) 1.2–2.0, p < 0.002] and hospitalization (OR: 1.5, 95% CI 1.2–1.8, p < 0.001) independently of sex, age, NT-proBNP, creatinine, and CRP. Bio-ADM statistically significantly improves the reference model in predicting mortality (added χ2 9.8, p = 0.002) and hospitalization (added χ2 14.1, p = 0.0002), and is associated with IV diuretic treatment and HF diagnosis at discharge. Plasma levels of bio-ADM sampled at ED presentation in acutely dyspneic patients are independently associated with 90-day mortality, hospitalization and indicate the need for decongestive therapy.
Reproducing Kernel Hilbert Space Associated with a Unitary Representation of a Groupoid
Authors: Drewnik Monika , Miller Tomasz , Pasternak-Winiarski Zbigniew
Published: June 2021

The aim of the paper is to create a link between the theory of reproducing kernel Hilbert spaces (RKHS) and the notion of a unitary representation of a group or of a groupoid. More specifically, it is demonstrated on one hand how to construct a positive definite kernel and an RKHS for a given unitary representation of a group(oid), and on the other hand how to retrieve the unitary representation of a group or a groupoid from a positive definite kernel defined on that group(oid) with the help of the Moore–Aronszajn theorem. The kernel constructed from the group(oid) representation is inspired by the kernel defined in terms of the convolution of functions on a locally compact group. Several illustrative examples of reproducing kernels related with unitary representations of groupoids are discussed in detail. The paper is concluded with the brief overview of the possible applications of the proposed constructions.
Geodesic Random Walks, Diffusion Processes and Brownian Motion on Finsler Manifolds
Authors: Ma Tianyu , Matveev Vladimir S. , Pavlyukevich Ilya
Published: June 2021

We show that geodesic random walks on a complete Finsler manifold of bounded geometry converge to a diffusion process which is, up to a drift, the Brownian motion corresponding to a Riemannian metric.
Neue Krankheiten mit Bluttranskriptomik entschlüsseln
Authors: Ulas Thomas , Aschenbrenner Anna C.
Published: June 2021

The COVID-19 pandemic is leading to increasing numbers of patients all over the world. Reports on a dysregulated immune system in the severe cases calls for a better characterization of the ongoing changes. To dissect COVID-19-driven immune host responses, we profiled whole blood transcriptomes enabling a data-driven stratification based on molecular phenotype. This analysis allowed prediction of patient subgroup-specific drug candidates targeting the dysregulated systemic immune response of the host.
Mikrobieller Plastikabbau im Meer: die Suche nach dem Unwahrscheinlichen
Authors: Oberbeckmann Sonja , Markert Stephanie , Labrenz Matthias
Published: June 2021

Microplastic particles have been found in all the world’s oceans. Since their surfaces are microbially colonised, research is currently determining whether microbes are able to degrade the synthetic polymers. We show that their contribution to the biodegradation of plastics seems to be extremely limited. Also, it is unlikely that microbes specialise in plastic degradation through evolutionary adaptation. This is not only due to the great diversity and simultaneous very low bioavailability of microplastics in the oceans, but also because it is energetically disadvantageous.
Integrating hydrogeological and second-order geo-electric indices in groundwater vulnerability mapping: A case study of alluvial environments
Authors: George Nyakno Jimmy
Published: June 2021

AVI (Aquifer vulnerability index), GOD (groundwater occurrence, overlying lithology and depth to the aquifer), GLSI (geo-electric layer susceptibility indexing) and S (longitudinal unit conductance) models were used to assess economically exploitable groundwater resource in the coastal environment of Akwa Ibom State, southern Nigeria. The models were employed in order to delineate groundwater into its category of vulnerability to contamination sources using the first- and second-order geo-electric indices as well as hydrogeological inputs. Vertical electrical sounding technique employing Schlumberger electrode configuration was carried out in 16 locations, close to logged boreholes with known aquifer core samples. Primary or first-order geo-electric indices (resistivity, thickness and depth) measured were used to determine S. The estimated aquifer hydraulic conductivity, K, calculated from grain size diameter and water resistivity values were used to calculate hydraulic resistance (C) used to estimate AVI. With the indices assigned to geo-electric parameters on the basis of their influences, GOD and FSLI were calculated using appropriate equations. The geologic sequence in the study area consists of geo-electric layers ranging from motley topsoil, argillites (clayey to fine sands) and arenites (medium to gravelly sands). Geo-electric parametric indices of aquifer overlying layers across the survey area were utilized to weigh the vulnerability of the underlying water-bearing resource to the contaminations from surface and near-surface, using vulnerability maps created. Geo-electrically derived model maps reflecting AVI, BOD, FLSI and S were compared to assess their conformity to the degree of predictability of groundwater vulnerability. The AVI model map shows range of values of log C ( −3.46—0.07) generally less than unity and hence indicating high vulnerability. GOD model tomographic map displays a range of 0.1–0.3, indicating that the aquifer with depth range of 20.5 to 113.1 m or mean depth of 72. 3 m is lowly susceptible to surface and near-surface impurities. Again, the FLSI map displays a range of FLSI index of 1.25 to 2.75, alluding that the aquifer underlying the protective layer has a low to moderate vulnerability. The S model has values ranging from 0.013 to 0.991S. As the map indicates, a fractional portion of the aquifer at the western (Ikot Abasi) part of the study area has moderate to good protection (moderate vulnerability) while weak to poor aquifer protection (high vulnerability) has poor protection. The S model in this analysis seems to overstate the degree of susceptibility to contamination than the AVI, GOD and GLSI models. From the models, the categorization of severity of aquifer vulnerability to contaminations is relatively location-dependent and can be assessed through the model tomographic maps generated.
Classification of groundwater suitability for irrigation purposes using a comprehensive approach based on the AHP and GIS techniques in North Kurdufan Province, Sudan
Authors: Eldaw Elsiddig , Huang Tao , Mohamed Adam Khalifa , Mahama Yahaya
Published: June 2021

Deterioration of groundwater quality due to drastic human interventions is rising at an alarming rate particularly in lower- and middle-income countries. Yet, limited research effort has been devoted to monitoring and ascertaining groundwater quality. The present study develops a comprehensive irrigation water quality index (IWQI) for rating water quality of shallow and deep aquifers in North Kurdufan province, Sudan. The new approach is developed to overcome the deficiencies of the existing irrigation indices and coming up with a unified decision for classifying water quality for irrigation purposes. Because of these indices like permeability index (PI), sodium absorption ratio (SAR), etc., depending on specific elements, entirely subjective, as well as the great variations in their results, particularly when classifying water quality. Thus, IWQI is created based on eight indices that are generally used to evaluate irrigation water quality, plus three physicochemical parameters have been proven an impact on water quality. The analytic hierarchy process (AHP) is applied to minimize the subjectivity at assign parameter weights under multiple criteria decision analysis tools (MCDA). The spatial distribution of IWQI agrees with the spatial distribution of the most parameters. The results of our approach reveal that the majority of samples are suitable for irrigation uses for both aquifers except few wells in the confined aquifer. Also, noted that there are very variations in the irrigation indices results for classifying water quality. The comparison result showed that the new index robust, fair calculations and has best classifying of water quality.
Dynamic Information Design: A Simple Problem on Optimal Sequential Information Disclosure
Authors: Farhadi Farzaneh , Teneketzis Demosthenis
Published: June 2021

We study a dynamic information design problem in a finite-horizon setting consisting of two strategic and long-term optimizing agents, namely a principal (he) and a detector (she). The principal observes the evolution of a Markov chain that has two states, one “good” and one “bad” absorbing state, and has to decide how to sequentially disclose information to the detector. The detector’s only information consists of the messages she receives from the principal. The detector’s objective is to detect as accurately as possible the time of the jump from the good to the bad state. The principal’s objective is to delay the detector as much as possible from detecting the jump to the bad state. For this setting, we determine the optimal strategies of the principal and the detector. The detector’s optimal strategy is described by time-varying thresholds on her posterior belief of the good state. We prove that it is optimal for the principal to give no information to the detector before a time threshold, run a mixed strategy to confuse the detector at the threshold time, and reveal the true state afterward. We present an algorithm that determines both the optimal time threshold and the optimal mixed strategy that could be employed by the principal. We show, through numerical experiments, that this optimal sequential mechanism outperforms any other information disclosure strategy presented in the literature. We also show that our results can be extended to the infinite-horizon problem, to the problem where the matrix of transition probabilities of the Markov chain is time-varying, and to the case where the Markov chain has more than two states and one of the states is absorbing.
A note on isoperimetric inequalities of Gromov hyperbolic manifolds and graphs
Authors: Martínez-Pérez Álvaro , Rodríguez José M.
Published: June 2021

We study in this paper the relationship of isoperimetric inequality and hyperbolicity for graphs and Riemannian manifolds. We obtain a characterization of graphs and Riemannian manifolds (with bounded local geometry) satisfying the (Cheeger) isoperimetric inequality, in terms of their Gromov boundary, improving similar results from a previous work. In particular, we prove that having a pole is a necessary condition to have isoperimetric inequality and, therefore, it can be removed as hypothesis.