bluuebunny/crossref_metadata_2025 huggingface dataset:
In Vitro Three‐Dimensional Liver Models for Nanomaterial DNA Damage Assessment
Authors: Llewellyn Samantha V. , Niemeijer Marije , Nymark Penny , Moné Martijn J. , van de Water Bob , Conway Gillian E. , Jenkins Gareth J. S. , Doak Shareen H.
Published: January 2021

Whilst the liver possesses the ability to repair and restore sections of damaged tissue following acute injury, prolonged exposure to engineered nanomaterials (ENM) may induce repetitive injury leading to chronic liver disease. Screening ENM cytotoxicity using 3D liver models has recently been performed, but a significant challenge has been the application of such in vitro models for evaluating ENM associated genotoxicity; a vital component of regulatory human health risk assessment. This review considers the benefits, limitations, and adaptations of specific in vitro approaches to assess DNA damage in the liver, whilst identifying critical advancements required to support a multitude of biochemical endpoints, focusing on nano(geno)toxicology (e.g., secondary genotoxicity, DNA damage, and repair following prolonged or repeated exposures).
Influence of the Z/E Isomerism on the Pathway Complexity of a Squaramide‐Based Macrocycle
Authors: Orvay Francisca , Cerdá Jesús , Rotger Carmen , Ortí Enrique , Aragó Juan , Costa Antonio , Soberats Bartolome
Published: January 2021

The rising interest on pathway complexity in supramolecular polymerization has prompted the finding of novel monomer designs able to stabilize kinetically trapped species and generate supramolecular polymorphs. In the present work, the exploitation of the Z/E (geometrical) isomerism of squaramide (SQ) units to produce various self‐assembled isoforms and complex supramolecular polymerization pathways in methylcyclohexane/CHCl3 mixtures is reported for the first time. This is achieved by using a new bissquaramidic macrocycle (MSq) that self‐assembles into two markedly different thermodynamic aggregates, AggA (discrete cyclic structures) and AggB (fibrillar structures), depending on the solvent composition and concentration. Remarkably, UV–vis, 1H NMR, and FT‐IR experiments together with quantum‐chemical calculations indicate that these two distinct aggregates are formed via two different hydrogen bonding patterns (side‐to‐side in AggA and head‐to‐tail in AggB) due to different conformations in the SQ units (Z,E in AggA and Z,Z in AggB). The ability of MSq to supramolecularly polymerize into two distinct aggregates is utilized to induce the kinetic‐to‐thermodynamic transformation from AggA to AggB, which occurs via an on‐pathway mechanism. It is believed that this system provides new insights for the design of potential supramolecular polymorphic materials by using squaramide units.
Strong and Robust Electrochemical Artificial Muscles by Ionic‐Liquid‐in‐Nanofiber‐Sheathed Carbon Nanotube Yarns
Authors: Ren Ming , Qiao Jian , Wang Yulian , Wu Kunjie , Dong Lizhong , Shen Xiaofan , Zhang Huichao , Yang Wei , Wu Yulong , Yong Zhenzhong , Chen Wei , Zhang Yongyi , Di Jiangtao , Li Qingwen
Published: January 2021

To address the lack of a suitable electrolyte that supports the stable operation of the electrochemical yarn muscles in air, an ionic‐liquid‐in‐nanofibers sheathed carbon nanotube (CNT) yarn muscle is prepared. The nanofibers serve as a separator to avoid the short‐circuiting of the yarns and a reservoir for ionic liquid. The ionic‐liquid‐in‐nanofiber‐sheathed yarn muscles are strong, providing an isometric stress of 10.8 MPa (about 31 times the skeletal muscles). The yarn muscles are highly robust, which can reversibly contract stably at such conditions as being knotted, wide‐range humidity (30 to 90 RH%) and temperature (25 to 70 °C), and long‐term cycling and storage in air. By utilizing the accumulated isometric stress, the yarn muscles achieve a high contraction rate of 36.3% s−1. The yarn muscles are tightly bundled to lift heavy weights and grasp objects. These unique features can make the strong and robust yarn muscles as a desirable actuation component for robotic devices.
Nitride‐Oxide‐Metal Heterostructure with Self‐Assembled Core–Shell Nanopillar Arrays: Effect of Ordering on Magneto‐Optical Properties
Authors: Wang Xuejing , Jian Jie , Wang Haohan , Liu Juncheng , Pachaury Yash , Lu Ping , Rutherford Bethany X. , Gao Xingyao , Xu Xiaoshan , El‐Azab Anter , Zhang Xinghang , Wang Haiyan
Published: January 2021

Magneto‐optical (MO) coupling incorporates photon‐induced change of magnetic polarization that can be adopted in ultrafast switching, optical isolators, mode convertors, and optical data storage components for advanced optical integrated circuits. However, integrating plasmonic, magnetic, and dielectric properties in one single material system poses challenges since one natural material can hardly possess all these functionalities. Here, co‐deposition of a three‐phase heterostructure composed of a durable conductive nitride matrix with embedded core–shell vertically aligned nanopillars, is demonstrated. The unique coupling between ferromagnetic NiO core and atomically sharp plasmonic Au shell enables strong MO activity out‐of‐plane at room temperature. Further, a template growth process is applied, which significantly enhances the ordering of the nanopillar array. The ordered nanostructure offers two schemes of spin polarization which result in stronger antisymmetry of Kerr rotation. The presented complex hybrid metamaterial platform with strong magnetic and optical anisotropies is promising for tunable and modulated all‐optical‐based nanodevices.
Prussian Blue Analogs and Their Derived Nanomaterials for Electrochemical Energy Storage and Electrocatalysis
Authors: Song Xuezhi , Song Shuyan , Wang Dan , Zhang Hongjie
Published: January 2021

Prussian blue analogs (PBAs), the oldest artificial cyanide‐based coordination polymers, possess open framework structures, large specific surface areas, uniform metal active sites, and tunable composition, showing significant perspective in electrochemical energy storage. These electrochemically active materials have also been converted to various functional metal containing nanomaterials, including carbon encapsulated metals/metal alloys, metal oxides, metal sulfides, metal phosphides, etc. originating from the multi‐element compositions as well as elaborate structure design. In this paper, a comprehensive review will be presented on the recent progresses in the development of PBA frameworks and their derivatives based electrode materials and electrocatalysts for electrochemical energy storage and conversion. In particular, it will focus on the synthesis of representative nanostructures, the structure design, and figure out the correlation between nanomaterials structure and electrochemical performance. Lastly, critical scientific challenges in this research area are also discussed and perspective directions for the future research in this field are provided, in order to provide a brand new vision into the further development of novel active materials for the next‐generation advanced electrochemical devices.
A design science research approach to closing the gap between the research and practice of project scheduling
Authors: Scales Jeff
Published: January 2021

This paper illustrates one researcher's experience of applying design science research (DSR) to the nexus between systems thinking and project scheduling. Project management has become increasingly popular in the decades since its advent but has changed little in that time. This is especially true because of its signature technique, project scheduling. Scheduling research however is vibrant and modern and even includes dynamic concepts such as learning curves in schedule construction. However, justifications for acquiring this level of systems literacy have not yet convinced the practice community. A similar gap is identified in management science, and a literature review yields two potential solutions: dissolving the subjective‐objective divide by adopting Critical Realism and using DSR as a framework for producing artefacts. This paper outlines how these concepts were applied to project scheduling, resulting in a new method for schedule construction that allows an expanded range of concepts to be included.
Effects of Weight‐Compatible Design on Ingot Solidification
Authors: Zhang Yan , Xu Changjun , Liu Ningning , Zhang Yuting , Xue Zhengguo
Published: January 2021

The problem of complex and various ingot moulds has bothered special steel enterprises. Herein, three ingot‐weight‐compatible (IWC) designs are described. The 39 tons mould is adapted to cast at most 45 tons of molten steel. The effect of three IWC designs on shrinkage cavity, porosity and macrosegregation is studied. The simulation is based on a polyphase coupled model for momentum, energy, and mass conservation equations. On the basis of the experimental results and previous literature, the interfacial heat transfer coefficient is established. Through finite difference method (FDM) simulation, the effect of the three IWC designs on the solidification is studied. The predictions of shrinkage porosity and macrosegregation are obtained. With the increase of ingot weight, the shrinkage cavity from the hot top is deeper in the three IWC designs. The Niyama criterion is found to be the condition under G/L0.5 < constant (G and L are the temperature gradient and cooling rate, respectively). With this criterion, the extent of centerline shrinkage porosity is predicted. Subsequently, utilizing the three compatible designs, the simulated results uncover that the centerline shrinkage porosity is serious. In addition, it is significant to note that the macrosegregation shows different characteristics.
Brucellosis: Prevalence with reference to East African community countries – A rapid review
Authors: Djangwani Juvenal , Ooko Abong’ George , Gicuku Njue Lucy , Kaindi Dasel W. M.
Published: January 2021

Brucellosis is a zoonotic disease which is endemic to certain regions of the world including Sub‐Saharan Africa. The aim of this article is to provide a recent and rapid review on brucellosis prevalence in East African Community (EAC) countries. Literature was obtained using Google Scholar search engine and screened for relevancy and fulfilment of criteria to 1, 17, 4, 4, 30 and 29 articles retained for brucellosis prevalence in Burundi, Kenya, Rwanda, South Sudan, Tanzania and Uganda. Recent literature (published in the last decade 2010 to 2019) was considered for prevalence results in this review. In EAC, livestock had an animal‐level prevalence of 0.2% to 43.8%, 0.0% to 20.0% and 0.0% to 13.8% for cattle, goats and sheep respectively. In humans, the prevalence varied mostly between 0.0% and 35.8%. In conclusion, brucellosis is quite prevalent in the region. The reported prevalence calls for plans or more efforts from individual member countries and from EAC, as a region, to control brucellosis.
Floods and the COVID‐19 pandemic—A new double hazard problem
Authors: Simonovic Slobodan P. , Kundzewicz Zbigniew W. , Wright Nigel
Published: January 2021

The coincidence of floods and coronavirus disease 2019 (COVID‐19) is a genuine multihazard problem. Since the beginning of 2020, many regions around the World have been experiencing this double hazard of serious flooding and the pandemic. There have been 70 countries with flood events occurring after detection of the country's first COVID‐19 case and hundreds of thousands of people have been evacuated. The main objective of this article is to assess challenges that arise from complex intersections between the threat multipliers and to provide guidance on how to address them effectively. We consider the limitations of our knowledge including “unknown unknowns.” During emergency evacuation, practicing social distancing can be very difficult. However, people are going to take action to respond to rising waters, even if it means breaking quarantine. This is an emergency manager's nightmare scenario: two potentially serious emergencies happening at once. During this unprecedented year (2020), we are experiencing one of the most challenging flood seasons we have seen in a while. Practical examples of issues and guides for managing floods and COVID‐19 are presented. We feel that a new approach is needed in dealing with multiple hazards. Our main messages are: a resilience approach is needed whether in response to floods or a pandemic; preparation is vital, in addition to defense; the responsible actors must be prepared with actions plans and command structure, while the general population must be involved in the discussions so that they are aware of the risk and the reasons for the actions they must take.

This article is categorized under:

Engineering Water > Methods
Adaptive sliding mode control of floating offshore wind turbine equipped by permanent magnet synchronous generator
Authors: Zhang Cheng , Plestan Franck
Published: January 2021

High‐order sliding mode control laws with gain adaptation algorithms are applied, in Region III, on a floating offshore wind turbine equipped by permanent magnet synchronous generator (PMSG). These adaptive control methods are especially efficient for systems with uncertainties and external perturbations and are well adapted to wind turbines systems. Such controllers can be implemented with very reduced knowledge of system model (only the relative degree is necessary) and strongly reduce the controller gains tuning effort. Simulations are made on Fatigue, Aerodynamics, Structures and Turbulence (FAST) software and compared with standard gain‐scheduled proportional–integral (PI) controllers.
Optimization of chromium(VI) removal by indigenous microalga (Chlamydomonas sp.)‐based biosorbent using response surface methodology
Authors: Ayele Abate , Suresh Arumuganainar , Benor Solomon , Konwarh Rocktotpal
Published: January 2021

Phycoremediation of heavy metals has garnered considerable recent research interest. In this study, an indigenous microalga (Chlamydomonas sp.)‐based biosorbent was employed for biosorption of Cr(VI) dissolved solids (Cr(VI)‐DS), optimized using response surface methodology (RSM). The effects of microalga concentration, pH, and contact time were studied with 250 mg Cr(VI)‐DS L−1. The biosorption of Cr(VI)‐DS was higher at acidic pH (94.17% at pH 4) than at alkaline conditions (68.53% at pH 10). The interaction of pH and microalga concentration exerted significant (p < 0.05) influence on the biosorption. Under the optimized parameters of 1.5 g microalga L−1, pH 4, and contact time of 30 min, a predicted biosorption of 91.31% and biosorption capacity of 152 mg Cr(VI)‐DS g−1 biomass were documented. FTIR analysis attested the electronegative surface functional groups of the microalgae biomass, bracketed together with its high biosorption potency. The study evinced the potential of the indigenous microalga for remediation of hexavalent chromium.

Practitioner points

Indigenous Ethiopian microalga (Chlamydomonas sp.) exhibited 94% Cr(VI) abatement with biosorption capacity of 152 mg Cr(VI) g−1.

FTIR analysis of the biosorbent divulged the presence of electronegative functional groups (amino, carboxyl, hydroxyl, and carbonyl groups).

Higher biosorption of Cr(VI)‐DS under acidic pH (94.17% at pH 4) than alkaline pH (68.53% at pH 10).

Significant (p < 0.05) interaction effect of pH and biomass concentration on the biosorption, evinced in RSM optimization

91% Cr(VI) removal achieved under optimal conditions of 1.5 g biosorbent L−1, 30 min of contact time, and pH 4.
Dynamic transcriptomic m5C and its regulatory role in RNA processing
Authors: Chen Yu‐Sheng , Yang Wen‐Lan , Zhao Yong‐Liang , Yang Yun‐Gui
Published: January 2021

RNA 5‐methylcytosine (m5C) is a prevalent RNA modification in multiple RNA species, including messenger RNAs (mRNAs), transfer RNAs (tRNAs), ribosomal RNAs (rRNAs), and noncoding RNAs (ncRNAs), and broadly distributed from archaea, prokaryotes to eukaryotes. The multiple detecting techniques of m5C have been developed, such as m5C‐RIP‐seq, miCLIP‐seq, AZA‐IP‐seq, RNA‐BisSeq, TAWO‐seq, and Nanopore sequencing. These high‐throughput techniques, combined with corresponding analysis pipeline, provide a precise m5C landscape contributing to the deciphering of its biological functions. The m5C modification is distributed along with mRNA and enriched around 5′UTR and 3′UTR, and conserved in tRNAs and rRNAs. It is dynamically regulated by its related enzymes, including methyltransferases (NSUN, DNMT, and TRDMT family members), demethylases (TET families and ALKBH1), and binding proteins (ALYREF and YBX1). So far, accumulative studies have revealed that m5C participates in a variety of RNA metabolism, including mRNA export, RNA stability, and translation. Depletion of m5C modification in the organism could cause dysfunction of mitochondria, drawback of stress response, frustration of gametogenesis and embryogenesis, abnormality of neuro and brain development, and has been implicated in cell migration and tumorigenesis. In this review, we provide a comprehensive summary of dynamic regulatory elements of RNA m5C, including methyltransferases (writers), demethylases (erasers), and binding proteins (readers). We also summarized the related detecting technologies and biological functions of the RNA 5‐methylcytosine, and provided future perspectives in m5C research.

This article is categorized under:

RNA Processing > RNA Editing and Modification
Application of an immobilized ionic liquid for the preparation of hydroxylamine via hydrolysis of cyclohexanone oxime
Authors: Wang Shuangyu , Liu Jiaqi , Cheng Peng , Li Zhihui , Zhang Dongsheng , Yang Qiusheng , Zhao Xinqiang , Wang Yanji
Published: January 2021

Preparation of hydroxylamine via hydrolysis of cyclohexanone oxime was studied over porous SiO2 supported acid ionic liquid catalyst. The catalyst [SPIPTES]CF3SO3@SiO2 was prepared through sol‐gel method and characterized by elemental analysis, IR and TG, etc. Various parameters such as reaction temperature and time, catalyst amount were investigated systematically. The optimized reaction conditions investigated were catalyst:cyclohexanone oxime (mass ratio) 4 : 1, conducted at 60 °C for 1 h. Since the present hydrolysis reaction is controlled by thermodynamics, the conversion of cyclohexanone oxime could not be very high. However, reasonable result was achieved under the optimized reaction conditions. Cyclohexanone oxime conversion was 38.41 % and NH2OH yield was 37.65 %. Additionally, combining experiments with density functional theory calculations, a possible catalyst structure and reaction pathway involved protonated cyclohexanone oxime mechanism was proposed for the present hydrolysis in this study.
Mixed boundary value problems for Rayleigh wave in a half‐plane with cubic anisotropy
Authors: Şahin Onur
Published: January 2021

The paper deals with mixed boundary value problems in an elastic half‐plane with cubic symmetry. The formulation of the problem depends on an asymptotic model derived for anisotropic materials. It is demonstrated that defining the displacements in terms of a pair of plane harmonic functions reduces the problem to a classical isotropic form, which can be formulated within the framework of the asymptotic hyperbolic–elliptic model developed for isotropic materials. As an example, a semi‐infinite rigid stamp moving at a constant speed along the surface is considered.
Liouville quantum gravity — holography, JT and matrices
Authors: Mertens Thomas G. , Turiaci Gustavo J.
Published: January 2021

Abstract

We study two-dimensional Liouville gravity and minimal string theory on spaces with fixed length boundaries. We find explicit formulas describing the gravitational dressing of bulk and boundary correlators in the disk. Their structure has a striking resemblance with observables in 2d BF (plus a boundary term), associated to a quantum deformation of SL(2, ℝ), a connection we develop in some detail. For the case of the (2, p) minimal string theory, we compare and match the results from the continuum approach with a matrix model calculation, and verify that in the large p limit the correlators match with Jackiw-Teitelboim gravity. We consider multi-boundary amplitudes that we write in terms of gluing bulk one-point functions using a quantum deformation of the Weil-Petersson volumes and gluing measures. Generating functions for genus zero Weil-Petersson volumes are derived, taking the large p limit. Finally, we present preliminary evidence that the bulk theory can be interpreted as a 2d dilaton gravity model with a sinh Φ dilaton potential.
Exploding operators for Majorana neutrino masses and beyond
Authors: Gargalionis John , Volkas Raymond R.
Published: January 2021

Abstract

Building UV completions of lepton-number-violating effective operators has proved to be a useful way of studying and classifying models of Majorana neutrino mass. In this paper we describe and implement an algorithm that systematises this model-building procedure. We use the algorithm to generate computational representations of all of the tree-level completions of the operators up to and including mass-dimension 11. Almost all of these correspond to models of radiative neutrino mass. Our work includes operators involving derivatives, updated estimates for the bounds on the new-physics scale associated with each operator, an analysis of various features of the models, and a look at some examples. We find that a number of operators do not admit any completions not also generating lower-dimensional operators or larger contributions to the neutrino mass, ruling them out as playing a dominant role in the neutrino-mass generation. Additionally, we show that there are at most five models containing three or fewer exotic multiplets that predict new physics that must lie below 100 TeV. Accompanying this work we also make available a searchable database containing all of our results and the code used to find the completions. We emphasise that our methods extend beyond the study of neutrino-mass models, and may be useful for generating completions of high-dimensional operators in other effective field theories. Example code: ref. [37].
Quiver origami: discrete gauging and folding
Authors: Bourget Antoine , Hanany Amihay , Miketa Dominik
Published: January 2021

Abstract

We study two types of discrete operations on Coulomb branches of 3d$$ \mathcal{N} $$
N
= 4 quiver gauge theories using both abelianisation and the monopole formula. We generalise previous work on discrete quotients of Coulomb branches and introduce novel wreathed quiver theories. We further study quiver folding which produces Coulomb branches of non-simply laced quivers. Our methods explicitly describe Coulomb branches in terms of generators and relations including mass deformations.
An emerging potential of metabolomics in multiple sclerosis: a comprehensive overview
Authors: Zahoor Insha , Rui Bin , Khan Junaid , Datta Indrani , Giri Shailendra
Published: January 2021

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the nervous system that primarily affects young adults. Although the exact etiology of the disease remains obscure, it is clear that alterations in the metabolome contribute to this process. As such, defining a reliable and disease-specific metabolome has tremendous potential as a diagnostic and therapeutic strategy for MS. Here, we provide an overview of studies aimed at identifying the role of metabolomics in MS. These offer new insights into disease pathophysiology and the contributions of metabolic pathways to this process, identify unique markers indicative of treatment responses, and demonstrate the therapeutic effects of drug-like metabolites in cellular and animal models of MS. By and large, the commonly perturbed pathways in MS and its preclinical model include lipid metabolism involving alpha-linoleic acid pathway, nucleotide metabolism, amino acid metabolism, tricarboxylic acid cycle,d-ornithine andd-arginine pathways with collective role in signaling and energy supply. The metabolomics studies suggest that metabolic profiling of MS patient samples may uncover biomarkers that will advance our understanding of disease pathogenesis and progression, reduce delays and mistakes in diagnosis, monitor the course of disease, and detect better drug targets, all of which will improve early therapeutic interventions and improve evaluation of response to these treatments.
Machine-learning algorithm that can improve the diagnostic accuracy of septic arthritis of the knee
Authors: Choi Eun-Seok , Sim Jae Ang , Na Young Gon , Seon Jong- Keun , Shin Hyun Dae
Published: January 2021

Purpose

Prompt diagnosis and treatment of septic arthritis of the knee is crucial. Nevertheless, the quality of evidence for the diagnosis of septic arthritis is low. In this study, the authors developed a machine learning-based diagnostic algorithm for septic arthritis of the native knee using clinical data in an emergency department and validated its diagnostic accuracy.

Methods

Patients (n = 326) who underwent synovial fluid analysis at the emergency department for suspected septic arthritis of the knee were enrolled. Septic arthritis was diagnosed in 164 of the patients (50.3%) using modified Newman criteria. Clinical characteristics of septic and inflammatory arthritis were compared. Area under the receiver-operating characteristic (ROC) curve (AUC) statistics was applied to evaluate the efficacy of each variable for the diagnosis of septic arthritis. The dataset was divided into independent training and test sets (comprising 80% and 20%, respectively, of the data). Supervised machine-learning techniques (random forest and eXtreme Gradient Boosting: XGBoost) were applied to develop a diagnostic model using the training dataset. The test dataset was subsequently used to validate the developed model. The ROC curves of the machine-learning model and each variable were compared.

Results

Synovial white blood cell (WBC) count was significantly higher in septic arthritis than in inflammatory arthritis in the multivariate analysis (P = 0.001). In the ROC comparison analysis, synovial WBC count yielded a significantly higher AUC than all other single variables (P = 0.002). The diagnostic model using the XGBoost algorithm yielded a higher AUC (0.831, 95% confidence interval 0.751–0.923) than synovial WBC count (0.740, 95% confidence interval 0.684–0.791; P = 0.033). The developed algorithm was deployed as a free access web-based application (www.septicknee.com).

Conclusion

The diagnosis of septic arthritis of the knee might be improved using a machine learning-based prediction model.

Level of evidence

Diagnostic study Level III (Case–control study).
Hydrolytic secretome engineering in Yarrowia lipolytica for consolidated bioprocessing on polysaccharide resources: review on starch, cellulose, xylan, and inulin
Authors: Celińska Ewelina , Nicaud Jean-Marc , Białas Wojciech
Published: January 2021

Consolidated bioprocessing (CBP) featuring concomitant hydrolysis of renewable substrates and microbial conversion into value-added biomolecules is considered to bring substantial benefits to the overall process efficiency. The biggest challenge in developing an economically feasible CBP process is identification of bifunctional biocatalyst merging the ability to utilize the substrate and convert it to value-added product with high efficiency. Yarrowia lipolytica is known for its exceptional performance in hydrophobic substrates assimilation and storage. On the other hand, its capacity to grow on plant-derived biomass is strongly limited. Still, its high potential to simultaneously overproduce several secretory proteins makes Y. lipolytica a platform of choice for expanding its substrate range to complex polysaccharides by engineering its hydrolytic secretome. This review provides an overview of different genetic engineering strategies advancing development of Y. lipolytica strains able to grow on the following four complex polysaccharides: starch, cellulose, xylan, and inulin. Much attention has been paid to genome mining studies uncovering native potential of this species to assimilate untypical sugars, as in many cases it turns out that dormant pathways are present in Y. lipolytica’s genome. In addition, the magnitude of the economic gain by CBP processing is here discussed and supported with adequate calculations based on simulated process models.

Key points

• The mini-review updates the knowledge on polysaccharide-utilizing Yarrowia lipolytica.

• Insight into molecular bases founding new biochemical qualities is provided.

• Model industrial processes were simulated and the associated costs were calculated.
Total knee arthroplasty improves the quality-adjusted life years in patients who exceeded their estimated life expectancy
Authors: Palazzuolo Michele , Antoniadis Alexander , Mahlouly Jaad , Wegrzyn Julien
Published: January 2021

Purpose

Total knee arthroplasty (TKA) is the treatment of choice for end-stage osteoarthritis though its risk-benefit ratio in elderly patients remains debated. This study aimed to evaluate the functional outcome, rates of complication and mortality, and quality-adjusted life years (QALY) in patients who exceeded their estimated life expectancy.

Methods

Ninety-seven TKA implanted in 86 patients who exceeded their estimated life expectancy at the time of TKA were prospectively included in our institutional joint registry and retrospectively analyzed. At latest follow-up, the functional outcome with the Knee Society Score (KSS), rates of complication and mortality, and QALY with utility value of EuroQol-5D score were evaluated.

Results

At a mean follow-up of three ± one years, the pre- to post-operative KSS improved significantly (p < 0.01). The rates of surgical and major medical complications related to TKA were 3% and 10%, respectively. The re-operation rate with readmission was 3% while no TKA was revised. The 30-day and one year mortality was 1% and 3%, respectively. The pre- to one year post-operative QALY improved significantly (p < 0.01). The cumulative QALY five years after TKA was four years. Assuming that these patients did not undergo TKA, their cumulative QALY at five years would have been only two years.

Conclusion

TKA is an effective procedure for the treatment of end-stage osteoarthritis in patients who exceeded their estimated life expectancy. TKA provided significant improvement in function and quality of life without adversely affecting overall morbidity and mortality. Therefore, TKA should not be contra-indicated in elderly patients based on their advanced age alone.
Decline in body condition in the Antarctic minke whale (Balaenoptera bonaerensis) in the Southern Ocean during the 1990s
Authors: Cunen Céline , Walløe Lars , Konishi Kenji , Hjort Nils Lid
Published: January 2021

Changes in the body condition of Antarctic minke whales (Balaenoptera bonaerensis) have been investigated in a number of studies, but remain contested. Here we provide a new analysis of body condition measurements, with particularly careful attention to the statistical model building and to model selection issues. We analyse body condition data for a large number (4704) of minke whales caught between 1987 and 2005. The data consist of five different variables related to body condition (fat weight, blubber thickness and girth) and a number of temporal, spatial and biological covariates. The body condition variables are analysed using linear mixed-effects models, for which we provide sound biological motivation. Further, we conduct model selection with the focused information criterion (FIC), reflecting the fact that we have a clearly specified research question, which leads us to a clear focus parameter of particular interest. We find that there has been a substantial decline in body condition over the study period (the net declines are estimated to 10% for fat weight, 7% for blubber thickness and 3% for the girth). Interestingly, there seems to be some differences in body condition trends between males and females and in different regions of the Antarctic. The decline in body condition could indicate major changes in the Antarctic ecosystem, in particular, increased competition from some larger krill-eating whale species.
Medical knowledge and clinical productivity: independently correlated metrics during radiology residency
Authors: Alkhalaf Zahraa S. A. , Yakar Derya , de Groot Jan Cees , Dierckx Rudi A. J. O. , Kwee Thomas C.
Published: January 2021

Objective

To determine the association between medical knowledge relevant to radiology practice (as measured by the Dutch radiology progress test [DRPT]) and clinical productivity during radiology residency.

Methods

This study analyzed the results of 6 DRPTs and time period–matched clinical production points of radiology residents affiliated to a tertiary care academic medical center between 2013 and 2016. The Spearman correlation analysis was performed to determine the association between DRPT percentile scores and average daily clinical production points. Linear regression analyses were performed to determine the association of DRPT percentile scores with average daily clinical production points, adjusted for age and gender of the radiology resident, and postgraduate year.

Results

Eighty-four DRPTs with time period–matched clinical production points were included. These 84 DRPTs were made by 29 radiology residents (18 males and 11 females) with a median age of 31 years (range: 26–38 years). The Spearman correlation coefficient between DRPT percentile scores and average daily clinical production points was 0.550 (95% confidence interval: 0.381–0.694) (p < 0.001), indicating a significant moderate positive association. On multivariate analysis, average daily clinical production points (β coefficient of 0.035, p = 0.003), female gender of the radiology resident (β coefficient of 12.690, p = 0.001), and postgraduate year (β coefficient of 10.179, p < 0.001) were significantly associated with DRPT percentile scores. These three independent variables achieved an adjusted R2 of 0.527.

Conclusion

Clinical productivity is independently associated with medical knowledge relevant to radiology practice during radiology residency. These findings indicate that clinical productivity of a resident could be a potentially relevant metric in a radiology training program.

Key Points

• There is a significant moderate correlation between medical knowledge relevant to radiology practice and clinical productivity during radiology residency.

• Medical knowledge relevant to radiology practice remains independently associated with clinical productivity during radiology residency after adjustment for postgraduate year and gender.

• Clinical productivity of a resident may be regarded as a potentially relevant metric in a radiology training program.
Nonlinear Network Dynamics with Consensus–Dissensus Bifurcation
Authors: Devriendt Karel , Lambiotte Renaud
Published: January 2021

We study a nonlinear dynamical system on networks inspired by the pitchfork bifurcation normal form. The system has several interesting interpretations: as an interconnection of several pitchfork systems, a gradient dynamical system and the dominating behaviour of a general class of nonlinear dynamical systems. The equilibrium behaviour of the system exhibits a global bifurcation with respect to the system parameter, with a transition from a single constant stationary state to a large range of possible stationary states. Our main result classifies the stability of (a subset of) these stationary states in terms of theeffective resistancesof the underlying graph; this classification clearly discerns the influence of the specific topology in which the local pitchfork systems are interconnected. We further describe exact solutions for graphs with external equitable partitions and characterize the basins of attraction on tree graphs. Our technical analysis is supplemented by a study of the system on a number of prototypical networks: tree graphs, complete graphs and barbell graphs. We describe a number of qualitative properties of the dynamics on these networks, with promising modelling consequences.
Kombination von simulationsbasiertem Lernen und Online-Learning in der Augenheilkunde
Authors: Deuchler Svenja , Sebode Christina , Ackermann Hanns , Schmack Ingo , Singh Pankaj , Kohnen Thomas , Koch Frank
Published: January 2021

Hintergrund

Die Ophthalmoskopie ist Bestandteil des medizinischen Curriculums, jedoch das Vermitteln der Inhalte oft unbefriedigend, da ein systematisches Lernen von Pathologien und deren Behandlungen dadurch erschwert ist, dass oftmals das passende Patientengut nicht zur Verfügung steht und dadurch gesunde Studenten einander untersuchen müssen. Aus diesem Grund haben wir eine Online-Plattform entwickelt, die in Kombination mit simulationsgestütztem Training sowohl das eigenständige als auch das angeleitete Lernen von Untersuchungsmethoden und Pathologien ermöglicht.

Ziel der Arbeit

Ziel der vorliegenden Arbeit war, ein Format für die Verbesserung der Lehre der direkten und indirekten Ophthalmoskopie im Studierendenunterricht zu evaluieren. Dabei wurden praktische Übungen an Virtual-Reality-basierten Simulatoren mit neu entwickelten und an den Lehrkatalog angepassten theoretischen Inhalten in der Online-Plattform EyesiNet verschränkt.

Material und Methoden

Die Studierenden bearbeiteten am ersten sowie am letzten Praktikumstag zufällig ausgewählte Fälle, die ihnen von den Eyesi Direct- und Eyesi Indirect-Simulatoren präsentiert wurden. Zwischen diesen beiden Einheiten konnten sie sich auf freiwilliger Basis mit den theoretischen Grundlagen typischer ophthalmologischer Krankheitsbilder im EyesiNet beschäftigen.

Ergebnisse

Eyesi Direct: Die Bewertung des Simulators ergab am ersten Praktikumstag für beide Gruppen keinen signifikant unterschiedlichen Wissensstand (p = 0,29). In der Gruppe OHNE Training (n = 54) ergab sich am letzten Praktikumstag mit p = 0,02 eine signifikante Verbesserung dieser Bewertung, jedoch mit einer geringen Effektgröße von 0,1. In der Gruppe MIT Training (n = 32) konnte mit p = 0,0004 eine hoch signifikante Verbesserung mit einer Effektgröße von 0,3 nach Rosenthal festgestellt werden. Eyesi Indirect: Die simulatorgestützte Bewertung ergab am ersten Praktikumstag keinen signifikanten Unterschied im Wissensstand der beiden Gruppen (p = 0,1). Nach dem Training schnitten zwar beide Gruppen etwas besser ab, jedoch ohne signifikanten Unterschied (OHNE Training p = 0,41/MIT Training p = 0,17).

Diskussion

Die Online-Plattform EyesiNet unterstützt beim Erlernen der wichtigsten Erkrankungsbilder. Lerninhalte werden reproduzierbar und auf für alle Lernenden standardisierte Weise zur Verfügung gestellt. Die Fertigkeiten der direkten Ophthalmoskopie sind hierbei deutlich schneller als die der indirekten Ophthalmoskopie zu erlernen.
Umsetzung eines digitalen Semesters Augenheilkunde während der COVID-19-Pandemie
Authors: Müller Andreas , Wagner Felix M. , Matlach Juliane , Zimmermann Marion , Troeber Heike , Ponto Katharina A. , Brill Anita , Schmidt Franziska , Pfeiffer Norbert , Schuster Alexander K. , Prokosch-Willing Verena
Published: January 2021

Hintergrund

Die erste Welle der COVID-19-Pandemie stellte Lehrende und Studierende vor große Herausforderungen, da die studentische Lehre trotz Einschränkung des Präsenzunterrichts stattzufinden hatte. Für Präsenzunterricht und Veranstaltungen mit Patientenkontakt mussten kurzfristig zwischen Mitte März und Beginn des Semesters im April Alternativen gestaltet werden.

Ziel der Arbeit

Beschreibung von Konzept und Umsetzung der studentischen Lehre an der Augenklinik der Universitätsmedizin Mainz in kompletter digitaler Form im Sommersemester 2020.

Konzeptvorstellung

Vorlesung, Untersuchungskurs und Praktikum der Augenheilkunde finden an der Universitätsmedizin Mainz im 5. und 6. Semester im Studiengang Humanmedizin statt. Grundlage der Neukonzeption war der bisherige Kursaufbau. Das umgesetzte Konzept umfasste Vorlesungen als Videopodcasts, Untersuchungsvideos, Online-Untersuchungskonferenzen, leitsymptomorientierte interaktive Patientenfälle, Operationsvideos, Anamnesevideos von Patienten und die Gestaltung eines „Live-Patientenzimmers“, in dem Patientenfälle inklusive Live-Übertragung des Spaltlampenbefundes und der Fundoskopie präsentiert wurden. Die Evaluation durch Studierende zeigte eine sehr gute Annahme des Konzeptes.

Diskussion

Es gelang innerhalb eines Zeitrahmens von 4 Wochen eine vollständige Überarbeitung und Digitalisierung des Kurses Augenheilkunde. Der größte Anteil der Neugestaltung beinhaltete die mediale Produktion von Untersuchungsvideos, interaktiven Patientenfällen und Videopodcasts der Vorlesungen. Diese digitalen Lehrkonzepte können auch in den nächsten Semestern nach Wiederaufnahme des Präsenzunterrichts genutzt werden und die Präsenzlehre in der Augenheilkunde unterstützen.
Benefit finding in long-term prostate cancer survivors
Authors: Lassmann Irène , Dinkel Andreas , Marten-Mittag Birgitt , Jahnen Matthias , Schulwitz Helga , Gschwend Jürgen E. , Herkommer Kathleen
Published: January 2021

Purpose

Benefit finding (BF) represents possible positive changes that people may experience after cancer diagnosis and treatment and has proven to be valuable to the psychological outcome. Knowledge of such beneficial consequences of prostate cancer (PCa) is limited in long-term survivors (> 5 years). Thus, the present study investigated the occurrence of benefit finding (BF) and its determinants in a large sample of (very-) long-term PCa survivors.

Methods

BF was assessed in 4252 PCa survivors from the German database “Familial Prostate Cancer” using the German version of the Benefit Finding Scale (BFS). Associations between BF and sociodemographic, clinical, and psychosocial (e.g., depressive and anxiety symptoms and perceived severity of the disease experience) variables were analyzed using hierarchical multiple linear regression analysis.

Results

Mean age at survey was 77.4 years (SD = 6.2) after a mean follow-up of 14.8 years (SD = 3.8). Mean BFS score was 3.14 (SD = 1.0); the prevalence of moderate-to-high BF (score ≥ 3) was 59.7%. Younger age at diagnosis, lower educational level, and higher perceived severity of the disease experience were predictive of BF. Objective disease severity or family history of PCa was not uniquely associated with BF.

Conclusions

BF occurs in older, (very-) long-term PCa survivors. Our findings suggest that the self-asserted severity of the disease experience in a patient’s biography is linked to BF in the survivorship course above all tangible sociodemographic and clinical factors.

Implications for cancer survivors

PCa survivors may express BF regardless of clinical disease severity. Treating urologists should consider inquiring BF to enrich a patient’s cancer narrative.
Regulation of SMC traction forces in human aortic thoracic aneurysms
Authors: Petit Claudie , Karkhaneh Yousefi Ali-Akbar , Ben Moussa Olfa , Michel Jean-Baptiste , Guignandon Alain , Avril Stéphane
Published: January 2021

Smooth muscle cells (SMCs) usually express a contractile phenotype in the healthy aorta. However, aortic SMCs have the ability to undergo profound changes in phenotype in response to changes in their extracellular environment, as occurs in ascending thoracic aortic aneurysms (ATAA). Accordingly, there is a pressing need to quantify the mechanobiological effects of these changes at single cell level. To address this need, we applied Traction Force Microscopy (TFM) on 759 cells coming from three primary healthy (AoPrim) human SMC lineages and three primary aneurysmal (AnevPrim) human SMC lineages, from age and gender matched donors. We measured the basal traction forces applied by each of these cells onto compliant hydrogels of different stiffness (4, 8, 12, 25 kPa). Although the range of force generation by SMCs suggested some heterogeneity, we observed that: 1. the traction forces were significantly larger on substrates of larger stiffness; 2. traction forces in AnevPrim were significantly higher than in AoPrim cells. We modelled computationally the dynamic force generation process in SMCs using the motor-clutch model and found that it accounts well for the stiffness-dependent traction forces. The existence of larger traction forces in the AnevPrim SMCs were related to the larger size of cells in these lineages. We conclude that phenotype changes occurring in ATAA, which were previously known to reduce the expression of elongated and contractile SMCs (rendering SMCs less responsive to vasoactive agents), tend also to induce stronger SMCs. Future work aims at understanding the causes of this alteration process in aortic aneurysms.
Direct determination of cellulosic glucan content in starch-containing samples
Authors: Sluiter Justin B. , Michel Katie P. , Addison Bennett , Zeng Yining , Michener William , Paterson Alexander L. , Perras Frédéric A. , Wolfrum Edward J.
Published: January 2021

A simple and highly selective analytical procedure is presented for the determination of cellulosic glucan content in samples that contain both cellulose and starch. This method eliminates the unacceptably large compounding errors of current two-measurement methods. If both starch and cellulose are present before analytical hydrolysis, both will be hydrolyzed to glucose causing bias and inaccuracy in the method. To prevent this interference, the removal of starch prior to cellulosic quantification is crucial. The method presented here is a concise in-series procedure with minimal measurements, eliminating large compounding errors. Sample preparation consists of a starch extraction employing enzymatic hydrolysis followed by a simple filtration and wash. The samples are then subjected to a two-stage acid hydrolysis. The concentration of glucose is determined by ion exchange high-performance liquid chromatography with a Pb2+column and a refractive index detector. The cellulosic glucan content is calculated based on the initial dry weight of the starting material. Data for the native biomass materials studied show excellent reproducibility, with coefficients of variance of 3.0% or less associated with the method. This selectivity for cellulosic glucan by the procedure was validated with several analytical techniques such as liquid chromatography coupled with mass spectrometry (LC–MS), Raman spectroscopy, and nuclear magnetic resonance.
Expansive learning in a change laboratory intervention for teachers
Authors: Augustsson Dennis
Published: January 2021

The theory of Expansive learning and the change laboratory (CL) methodology has been developed and applied in many studies on workplace learning and educational change. There are fewer studies made on small-scale interventions, exploring the longitudinal development of expansive learning in an educational change effort. This article examines a CL intervention performed in an upper secondary school in Sweden, with a small group of teachers engaged in a participatory design project. By identifying and analysing the relationship of the seven learning actions posited by the theory of expansive learning, the aim was to contribute to the discussion of the CL methodology and the empirical usability of the theory. The results showed that the seven expansive learning actions functioned as analytical tools to map the teachers learning and development, but the analysis also showed many deviations, disruptions and occurrence of practical actions of design in the process. This challenge the notions of cyclicity and ascension in the theory of expansive learning. Cyclicity might be desirable but not necessary for expansive learning which questions the need to first grasp the problem at a conceptual level before generating concrete solutions. The Findings in this study suggests the opposite; that the entanglement and parallel movement between the abstract and the concrete was a driving force for the teachers expansive learning and the design of new curricular units.