bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a Sensitive and Selective Optical Sensor for Measuring Ultra‐Trace Amounts of Fe(II) and Fe(III) Ions in Water
Authors: Al‐Qahtani Salhah D. , Shah Reem , Aljuhani Enas , Al‐Ahmed Zehbah A. , Habeebullah Turki M. , Saad Fawaz , Shahat Ahmed , El‐Metwaly Nashwa M.
Published: February 2022

A smart spectrophotometric method for the analytical determination of iron concentration in whichever oxidation state was developed using a novel optical sensor. The optical sensor was prepared by direct immobilization of novel synthesized chromophore, 5‐(((1,10‐phenanthrolin‐5‐yl)imino)methyl)‐2‐hydroxybenzoic acid (Phimhb) onto mesoporous silica nanospheres (MSNSs). The novel Phimhb chromophore has two sites, one is selective to Fe(II) ions and the other is selective to Fe(III) ions. The ions′ color can be seen with the human eye and monitored using spectrophotometric techniques or a smartphone. The influence of several parameters on the evaluation of iron ions content was studied and optimized. The proposed method was validated in terms of LOD, LOQ, linearity, and precision according to ICH guidelines. The optical Phimhb sensor has wide linear dynamic ranges with low detection limits of 4.94 ppb (1.83×10−7 mol L−1) and 10.4 ppb (3.85×10−7 mol L−1) for Fe(II) and Fe(III), respectively. The response time of this sensor for both ions was 60 s. The Phimhb sensor could be reproduced multiple times and used with a higher capacity each time. The effect of potential interfering ions on the estimation of Fe(II) and Fe(III) was investigated. The outcomes clarified that the prepared Phimhb sensor was very selective to Fe(II) and Fe(III) ions. Therefore, the Phimhb sensor had been successfully used in the determination of Fe(II) and Fe(III) in real water even without any pre‐concentration, it has high specificity.
A Straightforward Strategy for the Preparation of Diverse BODIPY Functionalized with Polyamines and Polyoxyethylenes**
Authors: Uvarov Denis Y. , Gorbatov Sergey A. , Kolokolova Marya K. , Kozlov Mikhail A. , Kolotirkina Natalya G. , Zavarzin Igor V. , Goze Christine , Denat Franck , Volkova Yulia A.
Published: February 2022

Novel derivatives of 4,4‐difluoro‐1,3,5,7,8‐pentamethyl‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) functionalized at the meso‐position with polyamines and polyoxyethylenes were synthesized through single‐step condensation of fluorogenic 8‐CH2Cl‐substituted BODIPY and corresponding amines. The systematic spectroscopic characterization (UV‐Vis, fluorescence) of stable in storage dyes bearing polyoxyethylene substituents was carried out. One compound showed promise for UV‐Vis and “off‐on” fluorescence Cu2+ detection in acetonitrile solutions. The ligand detects Cu2+ ions selectively in the presence of eighteen different alkaline earth metal cations.
Antioxidant Triggered Metallic 1T’ Phase Transformations of Chemically Exfoliated Tungsten Disulfide (WS2) Nanosheets
Authors: Kim Jun Yeob , Chae Soosang , Jang Woosun , Besford Quinn A. , Oh Jin Young , Lee Tae Il
Published: February 2022

Developing facile methods for inducing phase transformation between metallic and semiconducting 2D transition metal dichalcogenide (TMDC) materials is crucial toward leveraging their use in cutting‐edge energy devices. Herein, 2H‐to‐1T’ phase transformations in chemically exfoliated Tungsten Disulfide (WS2) nanosheet films, triggered by antioxidants toward highly conductive 2D TMDC electrode materials, are introduced. It is found that antioxidants cause residual LiOx compounds to reduce to Li metal, subsequently inducing 1T’ phase transformations in layered WS2 nanosheets, resulting in significantly enhanced conductivity across the overall films. Both thermoelectric devices and supercapacitors are fabricated utilizing the highly conductive 1T’ phase WS2 nanosheet films as a working electrode, allowing for outstanding performance due to the increased conductivity of the WS2 nanosheet films. The method constitutes a facile approach toward the use of chemically exfoliated 1T’ TMDC nanosheets for highly efficient energy device applications.
DNA‐Based Concatenated Encoding System for High‐Reliability and High‐Density Data Storage
Authors: Ren Yubin , Zhang Yi , Liu Yawei , Wu Qinglin , Su Juanjuan , Wang Fan , Chen Dong , Fan Chunhai , Liu Kai , Zhang Hongjie
Published: February 2022

Information storage based on DNA molecules provides a promising solution with advantages of low‐energy consumption, high storage efficiency, and long lifespan. However, there are only four natural nucleotides and DNA storage is thus limited by 2 bits per nucleotide. Here, artificial nucleotides into DNA data storage to achieve higher coding efficiency than 2 bits per nucleotide is introduced. To accommodate the characteristics of DNA synthesis and sequencing, two high‐reliability encoding systems suitable for four, six, and eight nucleotides, i.e., the RaptorQ‐Arithmetic‐LZW‐RS (RALR) and RaptorQ‐Arithmetic‐Base64‐RS (RABR) systems, are developed. The two concatenated encoding systems realize the advantages of correcting DNA sequence losses, correcting errors within DNA sequences, reducing homopolymers, and controlling specific nucleotide contents. The average coding efficiencies with error correction and without arithmetic compression by the RALR system using four, six, and eight nucleotides reach 1.27, 1.61, and 1.85 bits per nucleotide, respectively. While the average coding efficiencies by the RABR system are up to 1.50, 2.00, and 2.35 bits per nucleotide, respectively. The coding efficiency, versatility, and tunability of the developed artificial DNA systems might provide significant guidance for high‐reliability and high‐density data storage.
Influence of fiber characteristics on sulfate resistance of ambient‐cured geopolymer concrete
Authors: Kantarcı Fatih
Published: February 2022

The brittle nature of geopolymer concretes (GPCs) and curing process required in their production are factors that limit their practical applications. It was not detected any study investigating the effect of polypropylene (PP) fiber length and fiber content on sulfate resistance of GPC. The aim of this study is to investigate the effect of PP fibers used in different content and length on sulfate resistance of GPC cured under laboratory conditions. For this purpose, 6 and 12 mm length PP fibers were added to GPC at rate of 0.5, 1.0, and 1.5% by volume of concrete. Samples were cured in laboratory conditions for 28 days, and then exposed to 5% MgSO4 solutions. After the sulfate effect, the changes in physical and mechanical properties of GPC such as compressive strength, tensile strength, weight, ultrasonic pulse velocity (UPV), apparent porosity, and external appearance were investigated. In addition, microstructural analyzes were carried out with scanning electron microscope (SEM). As a result, it was determined that PP fiber additive at rate of 0.5% by volume significantly increased the sulfate resistance by preventing crack growth thanks to bridging function occur between binder phase and interface regions. Since the increased fiber length made it difficult to distribute the fibers homogeneously, 6 mm long PP fibers were more effective in improving the sulfate resistance.
Size effect and strain rate effect on seismic behavior of reinforced concrete beam‐column joints
Authors: Jin Liu , Wan Shunyin , Li Dong , Du Xiuli
Published: February 2022

The mechanical behavior of reinforced concrete (RC) beam‐column joints with different sizes under cyclic loads at varying rates was investigated, aiming at attaining a better understanding of the size effect and strain rate effect on RC beam‐column joints. First, a 2D mesoscale numerical model was established and verified by existing experimental results. Second, numerical tests regarding seismic performances of RC beam‐column joints were carried out. A total of four structural sizes and five strain rates were taken into consideration. The damage patterns, hysteretic curves, skeleton curves, the displacement ductility, the stiffness degradation, and the shear deformation of joints under different working conditions were analyzed. Finally, the size effect and strain rate effect on shear resistance and shear failure mechanism of joints were discussed. In addition, a semitheoretical formula considering structural sizes and strain rates for shear strength calculation was proposed and verified by available experimental data.
A 638‐gene phylogeny supports the recognition of twice as many species in the Malagasy endemic genusCapurodendron(Sapotaceae)
Authors: Boluda Carlos G. , Christe Camille , Naciri Yamama , Gautier Laurent
Published: February 2022

The Malagasy genusCapurodendroncurrently accommodates 26 described species and is the largest genus of the family Sapotaceae in Madagascar. These species are frequently logged because of their valued hardwood, which potentially puts them at risk of extinction. Species‐level identifications are often problematic, and this hinders both an accurate assessment of their conservation status and the development of effective protection measures. We sorted all the material (ca. 860 collections) available in the herbaria with significant collections for Madagascar into 47 putative species based on morphology. On 41 of these, for which we were able to retrieve suitable DNA, we conducted a phylogenetic reconstruction based on molecular sequences of 638 loci from 108Capurodendronspecimens, performing a target capture approach combined with next‐generation sequencing. Maximum likelihood (RAxML), pseudocoalescence (ASTRAL), and coalescence (STACEY) analyses showed thatCapurodendroncomprises two deeply divergent lineages. One, which includes a single species, is here newly described asC. subg.Reflexisepalabased on its distinctive morphology. The second lineage contains all remaining species, which seem to have resulted from a rapid radiation event. The phylogenetic tree provides good support for most of the species hypothesized based on morphology, with the exception of two species‐groups that we have named the Arid Complex and the Eastern Complex. As many as 20 species‐level lineages genetically distinct from any of the currently recognized species were identified, 17 of which were morphologically well‐characterized, representing strong candidates for new species. This would suggest thatCapurodendronis the most species‐rich endemic genus of plants in Madagascar. While 14 of these 20 clades are still under study, we here describe six species new to science:Capurodendron andrafiamenae(provisionally assessed as CR),C. aubrevillei(VU),C. birkinshawii(CR),C. naciriae(EN),C. randrianaivoi(CR), andC. sakarivorum(EN).Capurodendron oblongifoliumcomb. nov. (EN), previously regarded as a variety ofC. perrieri, represents a distinct lineage that is here recognized at the species level. The newly described species are illustrated by line drawings and photographs from the field, and a preliminary threat assessment is provided. We discuss the evolutionary history ofCapurodendronand also explore the question of node age estimates and their methodological limitations.
Recent Development in Metallic Nanoparticles for Breast Cancer Therapy and Diagnosis
Authors: Subhan Md Abdus , Muzibur Rahman Mohammed
Published: February 2022

Metal‐based nanoparticles are very promising for their applications in cancer diagnosis, drug delivery and therapy. Breast cancer is the major reason of death in woman especially in developed countries including EU and USA. Due to the heterogeneity of cancer cells, nanoparticles are effective as therapeutics and diagnostics. Anti‐cancer therapy of breast tumors is challenging because of highly metastatic progression of the disease to brain, bone, lung, and liver. Magnetic nanoparticles are crucial for metastatic breast cancer detection and protection. This review comprehensively discusses the application of nanomaterials as breast cancer therapy, therapeutics, and diagnostics.
Learning to Diagnose with Simulations: Introduction
Authors: Fischer Frank , Chernikova Olga , Opitz Ansgar
Published: February 2022

The introductory chapter provides a brief overview of the existing research strands on simulation-based learning and the notion of diagnostic competences. We believe that the domains of medical and teacher education can learn a lot from each other, especially when it comes to designing learning environments to promote professional development. We therefore emphasize the need for finding similarities across disciplines and instructional design features that can be effectively transferred between domains. This chapter also introduces the three-level coherence framework used throughout the other chapters of this book to enable comparisons between the presented approaches to simulation-based learning. This chapter ends with an overview of the chapters in the book.
Conclusions and Outlook: Toward more Systematic Research on the Use of Simulations in Higher Education
Authors: Opitz Ansgar , Fischer Martin R. , Seidel Tina , Fischer Frank
Published: February 2022

This final chapter starts with an overview of the simulations presented throughout the book. All of the simulations are tools to test and foster diagnostic competences. The simulations differ regarding diagnostic modes, sources of information, domains, and topics. The chapter then revisits the four overarching research questions from the introduction and lies out potential avenues for future research: (1) Diagnostic activities are a promising concept to explore the processes that are central for generating learning outcomes. (2) Optimal means of supporting learners in simulations might include the presentation of information, prompts, reflection phases, and role-taking. (3) Various characteristics of the learners, such as their expertise level, as well as the simulation, such as its authenticity, could mediate the effects of instructional support. (4) If simulations are adaptable, between learners or within the same simulation, they might increase the learning potential even further. The chapter then gives examples for how the projects presented in this book will address these four topics. The outlook ends with a call for interdisciplinary research.
Diagnosing the Instructional Quality of Biology Lessons Based on Staged Videos: Developing DiKoBi, A Video-Based Simulation
Authors: Kramer Maria , Stürmer Julia , Förtsch Christian , Seidel Tina , Ufer Stefan , Fischer Martin R. , Neuhaus Birgit J.
Published: February 2022

Identifying and interpreting challenging instructional situations is important for teacher performance in the classroom, thus also for instructional quality. This project examines classroom situations in which pre-service teachers diagnose effective teaching in terms of instructional quality in the context of biology lessons. The interdisciplinary collaboration combines expertise in research on teachers’ professional competence, video-based teaching, and computer-supported case-based learning in several contexts. The video-based simulation DiKoBi (German acronym for “diagnostic competences of biology teachers in biology classrooms”) was developed to investigate, measure, and foster pre-service teachers’ diagnostic skills concerning the instructional quality of biology lessons. Staged videos embedded in the video-based simulation DiKoBi show six different classroom situations, each focusing on one biology-specific instructional quality feature. Validity of the content and tasks in DiKoBi were examined in interviews using think-aloud protocols and expert-novice comparisons. In future research, intervention studies will be used to analyze the effects of knowledge acquisition and scaffolding during teachers’ diagnosing on their diagnostic skills concerning instructional quality.
Learning to Diagnose Secondary School Students’ Scientific Reasoning Skills in Physics and Biology: Video-Based Simulations for Pre-Service Teachers
Authors: Pickal Amadeus J. , Wecker Christof , Neuhaus Birgit J. , Girwidz Raimund
Published: February 2022

Since the ability to teach and therefore also diagnose not only subject-specific but also cross-domain skills are an important part of every teacher’s day-to-day work, we developed simulations to quantify and furthermore support the competence to diagnose secondary school students’ scientific reasoning skills. For this purpose, the simulations also include the possibility to rehearse interdisciplinary collaborations between physics and biology pre-service teachers. The simulations are video-based, containing short, scripted videos showing two students working on different inquiry tasks, including a physics and a biology experiment. Participants have to observe the students and can individually decide which pre-formulated questions they want to ask the students before, during and after the experiments to gather relevant information. The corresponding simulated answers are subsequently presented via additional videos. The information gained during the simulations is supposed to be used to diagnose the students’ scientific reasoning skills later in the process.
Live and Video Simulations of Medical History-Taking: Theoretical Background, Design, Development, and Validation of a Learning Environment
Authors: Fink Maximilian C. , Reitmeier Victoria , Siebeck Matthias , Fischer Frank , Fischer Martin R.
Published: February 2022

History-taking is an essential diagnostic situation and has long been an important objective of medical education in European countries and beyond. Thus, the research project presented here investigates facilitating diagnostic competences in live and video history-taking simulations. In this chapter, the theoretical background and the design, development, and validation process of the learning environment for this research project are described. In the first section, an overview of history-taking models is provided, the concept of diagnostic competences for history-taking is specified, and a summary of research on simulation-based learning and assessment of history-taking is given. The second section reports on the creation of knowledge tests and the live and video simulations. In the third section, results from a pilot study and an expert workshop are disclosed and findings from a validation study are provided. These findings indicate that the created simulations and knowledge tests measure separate but related aspects of diagnostic competences reliably and validly and may be used for assessment. In the final section, a summary is provided and future questions for research are presented with a focus on the adaptivity of scaffolds and simulation-based learning from atypical cases.
4d $$ \mathcal{N} $$ = 2 supergravity observables from Nekrasov-like partition functions
Authors: Hristov Kiril
Published: February 2022

Abstract

We reinterpret the OSV formula for the on-shell action/entropy function of asymptotically flat BPS black holes as a fixed point formula that is formally equivalent to a recent gluing proposal for asymptotically AdS4 black holes. This prompts a conjecture that the complete perturbative answer for the most general gravitational building block of 4d $$ \mathcal{N} $$
N
= 2 supergravity at a single fixed point takes the form of a Nekrasov-like partition function with equivariant parameters related to the higher-derivative expansion of the prepotential. In turn this leads to a simple localization-like proposal for a set of supersymmetric partition functions in (UV completed) 4d $$ \mathcal{N} $$
N
= 2 supergravity theories. The conjecture is shown to be in agreement with a number of available results for different BPS backgrounds with both Minkowski and AdS asymptotics. In particular, it follows that the OSV formula comes from the unrefined limit of the general expression including only the so-called 𝕎 tower of higher derivatives, while the on-shell action of pure (Euclidean) AdS4 with round S3 boundary comes from the NS limit that includes only the 𝕋 tower. Backgrounds preserving less supersymmetry, such as the under-rotating black holes in flat space, the holographic squashed S3, and the static/rotating twisted and non-twisted Kerr-Newman-like black holes in AdS4 lead to a more general refined version of the corresponding gravitational blocks as dictated by the supersymmetric gluing rules.
Area-filling curves
Authors: Nasso Maria Chiara , Volčič Aljoša
Published: February 2022

In this paper, we study area-filling curves, i.e. continuous and injective mappings defined on [0, 1] whose graph has positive measure. Current literature calls them “Osgood curves”, but their invention is due to H. Lebesgue. Stromberg and Tseng constructed homogeneous area-filling curves and offered an elegant example. We show that an appropriate variant of Knopp’s construction attains the same homogeneity result. In Section 4, we discuss briefly the existence of an “invasive” curve, i.e. a continuous and injective mapping from the half-open interval [0, 1[ to the unit square, whose image has measure 1. In the last section, we discuss several aspects of the Lance-Thomas curve, connecting it with the other construction due to Stromberg and Tseng.
Ovary activation correlates with the reproductive potential of honeybee (Apis mellifera) workers if they are in a foreign colony
Authors: Rojek W. , Kuszewska K.
Published: February 2022

In eusocial Hymenoptera, the laying of male-determined eggs by workers in an unrelated colony can be a powerful strategy for increasing direct fitness benefits. A recent study showed that honeybee rebels, which are workers that develop under queenless conditions and have high reproductive potential, drift to foreign colonies, with a preference for hopelessly queenless colonies, and act as reproductive parasites. In our experiment, by introducing 5-day-old rebels and normal workers into foreign queenright colonies, we discovered that only rebels developed a reproductive phenotype by activating their ovaries. In a similar experiment with 1-day-old workers, neither rebels nor normal workers displayed such a tendency. We suggest that workers’ reproductive potential could thus be a key parameter activating the ovaries in not only drifting workers but also workers acting as reproductive parasites. Our results also support the hypothesis that the colony recognition cue probably has an environmental, rather than a genetic, origin.
Was der (Allgemein- und Viszeral‑)Chirurg über die Thromboseprophylaxe wissen sollte
Authors: Meißler Saskia , Braun-Dullaeus Rüdiger , Hansen Michael , Meyer Frank
Published: February 2022

Ein persistierendes Problem im klinisch-operativen Alltag ist die operationsassoziierte venöse Thrombembolie mit ihren möglichen Komplikationen. Zu den ureigenen und elementaren Aufgaben des Chirurgen, sowohl des Operateurs als auch des klinisch tätigen Mediziners, gehören daher die kompetente und verlässlich realisierte Thrombembolieprophylaxe. Zahlreiche präventive Ansätze wurden entwickelt und im täglichen Management etabliert, ein Restrisiko für eine Thromboseentwicklung bleibt bestehen. Unter diesem Aspekt wurde eine Recherche insbesondere zur wissenschaftlichen Literatur mit Übersichts- und Leitliniencharakter zum Thema Risikostratifizierung, Prophylaxeverfahren allgemein und bei spezifischen Indikationen durchgeführt.
Caccioppoli-type estimates and $$\mathcal {H}$$-matrix approximations to inverses for FEM-BEM couplings
Authors: Faustmann Markus , Melenk Jens Markus , Parvizi Maryam
Published: February 2022

We consider three different methods for the coupling of the finite element method and the boundary element method, the Bielak–MacCamy coupling, the symmetric coupling, and the Johnson–Nédélec coupling. For each coupling, we provide discrete interior regularity estimates. As a consequence, we are able to prove the existence of exponentially convergent $$\mathcal {H}$$
H
-matrix approximants to the inverse matrices corresponding to the lowest order Galerkin discretizations of the couplings.
Cryogenic infrared spectroscopy provides mechanistic insight into the fragmentation of phospholipid silver adducts
Authors: Kirschbaum Carla , Greis Kim , Gewinner Sandy , Schöllkopf Wieland , Meijer Gerard , von Helden Gert , Pagel Kevin
Published: February 2022

Tandem mass spectrometry is arguably the most important analytical tool for structure elucidation of lipids and other metabolites. By fragmenting intact lipid ions, valuable structural information such as the lipid class and fatty acyl composition are readily obtainable. The information content of a fragment spectrum can often be increased by the addition of metal cations. In particular, the use of silver ions is deeply rooted in the history of lipidomics due to their propensity to coordinate both electron-rich heteroatoms and C = C bonds in aliphatic chains. Not surprisingly, coordination of silver ions was found to enable the distinction of sn-isomers in glycerolipids by inducing reproducible intensity differences in the fragment spectra, which could, however, not be rationalized. Here, we investigate the fragmentation behaviors of silver-adducted sn- and double bond glycerophospholipid isomers by probing fragment structures using cryogenic gas-phase infrared (IR) spectroscopy. Our results confirm that neutral headgroup loss from silver-adducted glycerophospholipids leads to dioxolane-type fragments generated by intramolecular cyclization. By combining high-resolution IR spectroscopy and computational modelling of silver-adducted fragments, we offer qualitative explanations for different fragmentation behaviors of glycerophospholipid isomers. Overall, the results demonstrate that gas-phase IR spectroscopy of fragment ions can significantly contribute to our understanding of lipid dissociation mechanisms and the influence of coordinating cations.

Graphical abstract
Anatomic Repair of Congenitally Corrected Transposition: Reappraisal of Eligibility Criteria
Authors: Weixler Viktoria H. M. , Kramer Peter , Murin Peter , Romanchenko Olga , Cho Mi-Young , Ovroutski Stanislav , Hübler Michael , Berger Felix , Photiadis Joachim
Published: February 2022

Several criteria to identify suitable candidates for anatomic repair in congenitally corrected transposition (cc-TGA) have been proposed. The purpose of this study was to critically re-evaluate adequacy of these recommendations in our patient cohort. All cc-TGA patients undergoing anatomic repair between 2010 and 2019 were reviewed. Evaluated eligibility criteria for repair included age ≤ 15 years, LV mass index ≥ 45–50 g/m2, LV mass/volume ratio > 0.9–1.5 and systolic LV to right ventricle pressure ratio > 70–90% among others. Repair failure was defined as postoperative early mortality or LV dysfunction requiring mechanical circulatory support. Twenty-five patients were included (median [interquartile range] age at surgery 1.8 years [0.7;6.6]; median postoperative follow-up 3.2 years [0.7;6.3]). Median preoperative LV ejection fraction was 60% [56;64], indexed LV mass 48.5 g/m2 [43.7;58.1] and LV mass/volume ratio 1.5 [1.1;1.6], respectively. A total of 12 patients (48%) did not meet at least one of the previously recommended criteria, however, all but two patients (92%) experienced favorable early outcome. Of 7 patients (28%) with indexed LV mass < 45 g/m2, 6 were successfully operated. There were two early repair failures (8%) with LV dysfunction: one patient died and one required mechanical circulatory support but recovered well. Surgery was performed successfully in patients with LV mass and volume Z-scores as low as − 2 and − 2.5, respectively. Anatomic correction for cc-TGA can be performed with excellent early outcome and is feasible even in patients with LV mass below previously recommended cut-offs. The use of LV mass and volume Z-scores might help to refine eligibility criteria.
Acute calcific periarthritis—a commonly misdiagnosed pathology
Authors: Dimmick Simon , Hayter Catherine , Linklater James
Published: February 2022

Acute calcific periarthritis (ACP) is a self-limiting, monoarticular, peri-articular process of dystrophic mineral deposition and adjacent inflammation. Patients present with a sudden onset of pain, localised swelling, erythema, tenderness and restricted range of motion. Symptoms reduce in severity within 4–7 days and self resolve in 3–4 weeks. ACP is commonly misdiagnosed, in particular, as infective or inflammatory pathologies such as septic arthritis and gout. This condition has specific imaging findings which allows differentiation from other disorders when combined with the clinical presentation. Prompt diagnosis results in appropriate management and reduces the likelihood of unnecessary diagnostic and therapeutic procedures.
Social immunity in the honey bee: do immune-challenged workers enter enforced or self-imposed exile?
Authors: Conroy Tarli E. , Holman Luke
Published: February 2022

Animals living in large colonies are especially vulnerable to infectious pathogens and may therefore have evolved additional defences. Eusocial insects supplement their physiological immune systems with ‘social immunity’, a set of adaptations that impedes the entrance, establishment, and spread of pathogens in the colony. We here find that honey bee workers (Apis mellifera) that had been experimentally immune-challenged with bacterial lipopolysaccharide (LPS) often exited the hive and subsequently died; some individuals were dragged out by other workers, while others appeared to leave voluntarily. In a second experiment, we found that healthy workers treated with surface chemicals from LPS-treated bees were evicted from the hive more often than controls, indicating that immune-challenged bees produce chemical cues or signals that elicit their eviction. Thirdly, we observed pairs of bees under lab conditions, and found that pairs spent more time apart when one member of the pair had received LPS, relative to controls. Our findings suggest that immune-challenged bees altruistically banish themselves, and that workers evict sick individuals which they identify using olfactory cues, putatively because of (kin) selection to limit the spread of pathogens within colonies.

Significance statement

Just as in humans, animals living in large groups must contend with infectious diseases. Social insects such as honey bees have evolved a range of behavioural and organisational defences against disease, collectively termed ‘social immunity’. Here, we describe experiments in which we introduced immune-stimulated bee workers into hives to study social immunity. We find that bees that were wounded or immune-challenged were more likely to leave the hive—resulting in their death—compared to healthy controls. Some of the bees leaving the hive were ejected by other workers, while some left the hive seemingly by choice: we thus find evidence for both ‘banishment’ of immune-challenged bees and self-imposed exile. Furthermore, using experiments transferring chemical signals between healthy and immune stimulated bees, we establish that the latter are identified for banishment by the chemicals present on their body surface.
Third trimester intrauterine fetal death: proposal for the assessment of the chronology of umbilical cord and placental thrombosis
Authors: Bonasoni Maria Paola , Muciaccia Barbara , Pelligra Caterina B. , Goldoni Matteo , Cecchi Rossana
Published: February 2022

The timing of umbilical cord and placental thrombosis in the third trimester intrauterine fetal death (TT-IUFD) may be fundamental for medico-legal purposes, when it undergoes medical litigation due to the absence of risk factors. Authors apply to human TT-IUFD cases a protocol, which includes histochemistry and immunohistochemistry (IHC) for the assessment of thrombi’s chronology. A total of 35 thrombi of umbilical cord and/or placenta were assessed: 2 in umbilical artery, 6 in umbilical vein, 15 in insertion, 10 in chorionic vessels, 1 in fetal renal vein, 1 in fetal brachiocephalic vein. Thrombi’s features were evaluated with hematoxylin–eosin, Picro-Mallory, Von Kossa, Perls, and immunohistochemistry for CD15, CD68, CD31, CD61, and Smooth Muscle Actin. The estimation of the age of the thrombi was established by applying neutrophils/macrophages ratio taking into consideration, according to literature, the presence of hemosiderophagi, calcium deposition, and angiogenesis. To estimate an approximate age of fresh thrombi (< 1 day), a non-linear regression model was tested. Results were compared to maternal risk factors, fetal time of death estimated at autopsy, mechanism, and cause of death. Our study confirms that the maternal risk factors for fetal intrauterine death and the pathologies of the cord, followed by those of the placental parenchyma, are the conditions that are most frequently associated with the presence of thrombi. Results obtained with histological stainings document that the neutrophile/macrophage ratio is a useful tool for determining placental thrombi’s age. Age estimation of thrombi on the first day is very challenging; therefore, the study presented suggests the N/M ratio as a parameter to be used, together with others, i.e., hemosiderophagi, calcium deposition, and angiogenesis, for thrombi’s age determination, and hypothesizes that its usefulness regards particularly the first days when all other parameters are negative.
Lean mass sparing in resistance-trained athletes during caloric restriction: the role of resistance training volume
Authors: Roth C. , Schoenfeld B. J. , Behringer M.
Published: February 2022

Many sports employ caloric restriction (CR) to reduce athletes’ body mass. During these phases, resistance training (RT) volume is often reduced to accommodate recovery demands. Since RT volume is a well-known anabolic stimulus, this review investigates whether a higher training volume helps to spare lean mass during CR. A total of 15 studies met inclusion criteria. The extracted data allowed calculation of total tonnage lifted (repetitions × sets × intensity load) or weekly sets per muscle group for only 4 of the 15 studies, with RT volume being highly dependent on the examined muscle group as well as weekly training frequency per muscle group. Studies involving high RT volume programs (≥ 10 weekly sets per muscle group) revealed low-to-no (mostly female) lean mass loss. Additionally, studies increasing RT volume during CR over time appeared to demonstrate no-to-low lean mass loss when compared to studies reducing RT volume. Since data regarding RT variables applied were incomplete in most of the included studies, evidence is insufficient to conclude that a higher RT volume is better suited to spare lean mass during CR, although data seem to favor higher volumes in female athletes during CR. Moreover, the data appear to suggest that increasing RT volume during CR over time might be more effective in ameliorating CR-induced atrophy in both male and female resistance-trained athletes when compared to studies reducing RT volume. The effects of CR on lean mass sparing seem to be mediated by training experience, pre-diet volume, and energy deficit, with, on average, women tending to spare more lean mass than men. Potential explanatory mechanisms for enhanced lean mass sparing include a preserved endocrine milieu as well as heightened anabolic signaling.
Vertical traction device prevents abdominal wall retraction and facilitates early primary fascial closure of septic and non-septic open abdomen
Authors: Fung Stephen , Ashmawy Hany , Krieglstein Christian , Halama Thomas , Schilawa Dustin , Fuckert Oliver , Hees Anita , Kröpil Feride , Rehders Alexander , Lehwald-Tywuschik Nadja C. , Knoefel Wolfram Trudo
Published: February 2022

Purpose

One of the major challenges in the management of patients with septic and non-septic open abdomen (OA) is to control abdominal wall retraction. The aim of this study was to evaluate the impact of a novel vertical traction device (VTD) on primary fascial closure (PFC) and prevention of fascial retraction.

Methods

Twenty patients treated with OA were included in this retrospective multicenter study. All patients were initially stabilized with laparostomy and the abdomen temporarily sealed either with a Bogotá bag or a negative pressure wound therapy system (NPWT).

Results

The mean duration of OA and fascia-to-fascia distance (FTF) prior to the VTD application were 3 days and 15 cm, respectively. At relook laparotomy 48 h after VTD implementation, the mean FTF distance significantly decreased to 10 cm (p = 0.0081). In all cases, PFC was achieved after a mean period of 7 days. Twelve patients received the VTD in combination with a NPWT, whereas in eight patients, the device was combined with an alternative temporary abdominal closure system (TAC). Although not statistically significant, the FTF distance remarkably decreased in both groups at relook laparotomy 48 h following the device implementation. The mean periods of PFC for patients with septic and non-septic OA were comparable (7.5 vs. 7 days). During follow-up, two patients developed an incisional hernia.

Conclusion

Vertical traction device prevents fascial retraction and facilitates early PFC in OA. In combination with NPWT, rapid fascial closure of large abdominal defects can be achieved.
Effective hyperelastic material parameters from microstructures constructed using the planar Boolean model
Authors: Brändel Matthias , Brands Dominik , Maike Simon , Rheinbach Oliver , Schröder Jörg , Schwarz Alexander , Stoyan Dietrich
Published: February 2022

We construct two-dimensional, two-phase random heterogeneous microstructures by stochastic simulation using the planar Boolean model, which is a random collection of overlapping grains. The structures obtained are discretized using finite elements. A heterogeneous Neo-Hooke law is assumed for the phases of the microstructure, and tension tests are simulated for ensembles of microstructure samples. We determine effective material parameters, i.e., the effective Lamé moduli $$\lambda ^*$$

λ
∗

and $$\mu ^*$$

μ
∗

, on the macroscale by fitting a macroscopic material model to the microscopic stress data, using stress averaging over many microstructure samples. The effective parameters $$\lambda ^*$$

λ
∗

and $$\mu ^*$$

μ
∗

are considered as functions of the microscale material parameters and the geometric parameters of the Boolean model including the grain shape. We also consider the size of the Representative Volume Element (RVE) given a precision and an ensemble size. We use structured and unstructured meshes and also provide a comparison with the FE$$^2$$

2

method.
A reinforcement learning-based approach for imputing missing data
Authors: Awan Saqib Ejaz , Bennamoun Mohammed , Sohel Ferdous , Sanfilippo Frank , Dwivedi Girish
Published: February 2022

Missing data is a major problem in real-world datasets, which hinders the performance of data analytics. Conventional data imputation schemes such as univariate single imputation replace missing values in each column with the same approximated value. These univariate single imputation techniques underestimate the variance of the imputed values. On the other hand, multivariate imputation explores the relationships between different columns of data, to impute the missing values. Reinforcement Learning (RL) is a machine learning paradigm where the agent learns by taking actions and receiving rewards in response, to achieve its goal. In this work, we propose an RL-based approach to impute missing data by learning a policy to impute data through an action-reward-based experience. Our approach imputes missing values in a column by working only on the same column (similar to univariate single imputation) but imputes the missing values in the column with different values thus keeping the variance in the imputed values. We report superior performance of our approach, compared with other imputation techniques, on a number of datasets.
Evaluation of fog application placement algorithms: a survey
Authors: Smolka Sven , Mann Zoltán Ádám
Published: February 2022

Recently, the concept of cloud computing has been extended towards the network edge. Devices near the network edge, called fog nodes, offer computing capabilities with low latency to nearby end devices. In the resulting fog computing paradigm (also called edge computing), application components can be deployed to a distributed infrastructure, comprising both cloud data centers and fog nodes. The decision which infrastructure nodes should host which application components has a large impact on important system parameters like performance and energy consumption. Several algorithms have been proposed to find a good placement of applications on a fog infrastructure. In most cases, the proposed algorithms were evaluated experimentally by the respective authors. In the absence of a theoretical analysis, a thorough and systematic empirical evaluation is of key importance for being able to make sound conclusions about the suitability of the algorithms. The aim of this paper is to survey how application placement algorithms for fog computing are evaluated in the literature. In particular, we identify good and bad practices that should be utilized respectively avoided when evaluating such algorithms.
The association between molar incisor hypomineralization and oral health-related quality of life: a cross-sectional study
Authors: Elhennawy K. , Rajjoub O. , Reissmann D. R. , Doueiri M.-S. , Hamad R. , Sierwald I. , Wiedemann V. , Bekes K. , Jost-Brinkmann P.-G.
Published: February 2022

Objectives

We aimed to assess the association between molar incisor hypomineralization (MIH) and the oral health-related quality of life (OHRQoL) in a group of 7- to 14-year-old children in Berlin, Germany.

Materials and methods

The cross-sectional study consisted of a consecutive sample of 317 children, aged 7–14 years (49% girls, 51% boys; mean age, 8.71). Data were collected between June 2018 and December 2019. MIH was diagnosed using the criteria of the European Academy of Paediatric Dentistry. OHRQoL was assessed using the German 19-item version of the Child Oral Health Impact Profile (COHIP-G19). Differences in COHIP-19 summary scores between controls without MIH and MIH patients and with regards to MIH severity were tested for statistical significance using t test and analysis of variance (ANOVA), respectively.

Results

Data were obtained for 217 untreated MIH patients and 100 controls. OHRQoL of MIH patients was significantly more impaired than of controls indicated by COHIP-19 mean scores (60.9 ± 10.7 vs. 67.9 ± 7.8; p < 0.001). Patients with severe MIH (59.6 ± 11.0) reported significantly worse OHRQoL than patients with mild MIH (63.6 ± 9.1; p = 0.013).

Conclusions

MIH has a significant negative impact on the children’s OHRQoL. Patients with severe MIH experience a greater negative impact on OHRQoL than those diagnosed with mild MIH.

Clinical significance

MIH is one of the major dental problems of our time; pediatric dentists should be aware of its impact on the OHRQoL of the patient.
Approximating the discrete time-cost tradeoff problem with bounded depth
Authors: Daboul Siad , Held Stephan , Vygen Jens
Published: February 2022

We revisit the deadline version of the discrete time-cost tradeoff problem for the special case of bounded depth. Such instances occur for example in VLSI design. The depth of an instance is the number of jobs in a longest chain and is denoted by d. We prove new upper and lower bounds on the approximability. First we observe that the problem can be regarded as a special case of finding a minimum-weight vertex cover in a d-partite hypergraph. Next, we study the natural LP relaxation, which can be solved in polynomial time for fixed d and—for time-cost tradeoff instances—up to an arbitrarily small error in general. Improving on prior work of Lovász and of Aharoni, Holzman and Krivelevich, we describe a deterministic algorithm with approximation ratio slightly less than $$\frac{d}{2}$$

d
2

for minimum-weight vertex cover in d-partite hypergraphs for fixed d and given d-partition. This is tight and yields also a $$\frac{d}{2}$$

d
2

-approximation algorithm for general time-cost tradeoff instances, even if d is not fixed. We also study the inapproximability and show that no better approximation ratio than $$\frac{d+2}{4}$$

d
+
2

4

is possible, assuming the Unique Games Conjecture and $$\text {P}\ne \text {NP}$$

P
≠
NP

. This strengthens a result of Svensson [21], who showed that under the same assumptions no constant-factor approximation algorithm exists for general time-cost tradeoff instances (of unbounded depth). Previously, only APX-hardness was known for bounded depth.
What Are the Physical Demands of Sexual Intercourse? A Systematic Review of the Literature
Authors: Oliva-Lozano José M. , Alacid Fernando , López-Miñarro Pedro A. , Muyor José M.
Published: February 2022

The aim of this study was to systematically review the literature investigating the physical demands of sexual intercourse and to synthesize the evidence related to this research topic. Original studies published on PubMed, Scopus, and Web of Science up until April 2020 were examined. The Effective Public Health Practice Project scale was used to assess the methodological quality of each study. Eighteen studies analyzed physical demands during sexual intercourse through the physiological demands (n = 14) and kinematics (n = 4) of sexual intercourse. Sexual intercourse can elicit an energy expenditure of ~ 100 kcal (or ~ 6 metabolic equivalent units, METs) during the activity, mean heart rates between ~ 90 and ~ 130 beats per minute (bpm), and peak heart rates up to ~ 170 bpm. However, these physical demands may vary depending on health status, intercourse position, activity duration, intercourse phase, and sex differences. The movement pattern was cyclic in all positions and the greatest demands in lumbar spine flexion were found in the missionary positions for women. Missionary and side-lying positions elicited the greatest lumbar flexion movement in men. Regarding the movement of the hip joint during sexual intercourse, flexion, abduction, and external rotation mainly characterized the woman’s movement while external rotation did so in the man. In conclusion, sexual intercourse may elicit moderate intensity physical demands, but these demands vary depending on contextual variables. In addition, not only studies combining physiological and kinematic analyses are necessary but also more high-quality studies need to be published in order to have a better understanding of the physical demands of sexual intercourse.
Molecular mechanisms and differences in lynch syndrome developing into colorectal cancer and endometrial cancer based on gene expression, methylation, and mutation analysis
Authors: Li Hongfeng , Sun Liwei , Zhuang Yan , Tian Caijuan , Yan Fang , Zhang Zhenzhen , Hu Yuanjing , Liu Pengfei
Published: February 2022

Purpose

The aim of this study was to screen biomarkers specific to Lynch syndrome (LS) with colorectal cancer (CRC) or endometrial cancer (EC) to explore the mechanisms by which LS develops into CRC and EC and their differences.

Methods

Differentially expressed or differentially methylated genes and differential mutations were identified in 10 LS, 50 CRC, and 50 EC patients from TCGA, and genes overlapping between LS and CRC or EC (named SGs-LCs and SGs-LEs, respectively) were identified. Afterward, we annotated the enriched GO terms and pathways and constructed a protein–protein interaction (PPI) network. Finally, samples from 10 clinical cases with MSI-H/MSS CRC and EC were collected to verify the mutations and their correlations with five LS pathogenic genes in the SGs-LCs and SGs-LEs.

Results

A total of 494 SGs-LCs and 104 SGs-LEs were identified and enriched in 106 and 14 GO terms, respectively. There were great differences in the gene count and enriched terms between SGs-LCs and SGs-LEs. In the PPI network,SST,GCG,SNAP25, andNPYhad the highest degree of connection among the SGs-LCs, andKIF20AandNUF2had the highest degree of connection among the SGs-LE. In the SGs-LCs and SGs-LEs, the genes whose expression levels affected the survival of LS, CRC or EC patients were quite different.

Conclusions

COL11A1was found to be mutated in MSS CRC patients, similar to the mutations ofMSH6.SST,GCG,SNAP25, andNPYmay be biomarkers for the development of LS into CRC, andKIF20AandNUF2may be markers of LS developing into EC.