bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomechanical Effects of Chronic Ankle Instability on the Talar Cartilage Matrix: The Value of T1ρ Relaxation Mapping Without and With Mechanical Loading
Authors: Lange Thomas , Sturm Lukas , Jungmann Pia M. , Jung Matthias , Ovsepyan Spartak , Reisert Marco , Schmal Hagen , Wenning Markus
Published: May 2022

Background

T1ρ mapping has been proposed for the detection of early cartilage degeneration associated with chronic ankle instability (CAI). However, there are limited data surrounding the influence of ankle loading on T1ρ relaxation.

Purpose

To evaluate T1ρ relaxation times of talar cartilage, as an indicator of early degenerative changes, associated with CAI and to investigate the influence of acute axial in situ loading on T1ρ values in CAI patients and healthy controls.

Study Type

Prospective.

Subjects

A total of 9 patients (age = 21.8 ± 2.5 years, male/female = 2/7) with chronic ankle instability and 18 healthy control subjects (age = 22.8 ± 3.6 years, male/female = 5/13).

Field Strength

3 T.

Sequence

3D gradient echo fast low‐angle shot (FLASH) sequence augmented with a variable spin‐lock preparation period.

Assessment

Ankle T1ρ mapping was performed without and with axial loading of 500 N. The talar cartilage was segmented in five coronal slices covering the central talocrural joint. Median talar T1ρ values were separately calculated for the medial and lateral facets.

Statistical Tests

Mann–Whitney U and Wilcoxon signed‐rank tests, significance level: P < 0.05.

Results

For the combined cohorts, the statistical analysis yielded significantly lower T1ρ values with loading compared to the no‐load measurement for both the lateral (no load: [51.0 ± 4.0] msec, load: [49.5 ± 5.4] msec) as well as the medial compartment (no load: [50.0 ± 5.4] msec, load: [47.8 ± 6.8] msec). In the unloaded scans, the CAI patients showed significantly increased talar T1ρ values ([53.0 ± 7.4] mse ) compared to the healthy control subjects ([48.8 ± 4.1] msec) in the medial compartment.

Data Conclusion

Increased talar T1ρ relaxation times in CAI patients compared to healthy controls suggest that T1ρ relaxation is a sensitive biomarker for CAI‐induced early‐stage cartilage degeneration. However, the load‐induced T1ρ change did not prove to be a viable marker for the altered biomechanical properties of the hyaline talar cartilage.

Level of Evidence

2

Level of Efficacy

Stage 2.
Deficient precipitation sensitivity to Sahel land surface forcings among CMIP5 models
Authors: Wang Fuyao , Notaro Michael , Yu Yan , Mao Jiafu
Published: May 2022

The overall performance of the simulated seasonal precipitation response to local terrestrial forcings, namely vegetation abundance and soil moisture, in the Sahel among the Coupled Model Intercomparison Project Phase Five (CMIP5) Earth System Models (ESMs) is systematically investigated and compared with its observational counterpart using a multivariate statistical method. The observed seasonal precipitation response is evaluated against a large ensemble of observational, reanalysis, and satellite data sets to provide quantification of uncertainties. The behaviour of models with and without a Dynamic Global Vegetation Model (DGVM) component is also explored, along with the mechanisms responsible for terrestrial feedback on rainfall. In general, the CMIP5 models can reasonably capture the seasonal evolution of Sahel precipitation and soil moisture, albeit with wet biases during the pre‐monsoon period and dry biases during the peak monsoon period. The non‐DGVM ESMs simulate comparable leaf area indices (LAIs) with observations, while DGVM‐enabled ESMs simulate too much year‐round LAI. The variance of precipitation that is attributed to oceanic forcings in CMIP5 is comparable with observations; however, the variance of precipitation that is attributed to terrestrial forcings is smaller in CMIP5 models than observed, especially for non‐DGVM ESMs. CMIP5 models, especially those without DGVMs, undervalue precipitation's observed response strength to soil moisture anomalies. In both observations and CMIP5 models, none of the atmospheric variables show significant responses to direct vegetation forcing, except for the response in transpiration. Although vegetation has minimal direct effect on the atmospheric state, it can affect the atmosphere by modifying soil moisture and transpiration rate indirectly, which helps explain the more realistic simulation of rainfall in DGVM‐enabled ESMs than non‐DGVM ESMs. Coupling of an ESM to a DGVM is critical in generating reasonable land–atmosphere feedback and examining future ecological and climatic changes over the Sahel.
Disrupting marketing realities: A research agenda for investigating the psychological mechanisms of next‐generation experiences with reality‐enhancing technologies
Authors: Hilken Tim , Keeling Debbie I. , Chylinski Mathew , de Ruyter Ko , Golf Papez Maja , Heller Jonas , Mahr Dominik , Alimamy Saifeddin
Published: May 2022

Reality‐enhancing technologies such as augmented reality and virtual reality are rapidly becoming a part of everyday life. Seizing this moment, we set out a research agenda for studying the psychological mechanisms underpinning consumer experiences with these new technologies, structured around four application areas: (1) delivering innovative offerings, (2) supporting sustainability and consumer well‐being interventions, (3) balancing value cocreation and privacy concerns, and (4) achieving new modes and means of impact. For each area, we identify research directions that can guide the development and use of reality‐enhancing technologies for the realization of next‐generation consumer experiences. We explicitly balance potential advantages and disadvantages, thus encouraging researchers and practitioners to prioritize developing the “purpose” of these technologies, by focusing on the psychological mechanisms that underlie their use, over the technological development of their “pixels.” In this way, we guide the impactful development of reality‐enhancing technologies for applications with significance for consumers and firms.
Novel Dithienopyrrole‐Based Conjugated Copolymers: Importance of Backbone Planarity in Achieving High Electrical Conductivity and Thermoelectric Performance
Authors: Lee Hansol , Li Huan , Kim Young‐Shin , Park Sang Min , Lee Dongki , Lee Sungjoo , Lee Hwa Sung , Kim Yun‐Hi , Kang Boseok
Published: May 2022

The development of conjugated polymers with structures that are suitable for efficient molecular doping and charge transport is a key challenge in the construction of high‐performance conjugated polymer‐based thermoelectric devices. In this study, three novel conjugated polymers based on dithienopyrrole (DTP) are synthesized and their thermoelectric properties are compared. When doped with p‐dopant, a donor–acceptor type copolymer, DPP‐MeDTP, exhibits higher electrical conductivity and thermoelectric power factor compared to the other donor–donor type copolymers. The high electrical conductivity of DPP‐MeDTP compared to the other polymers originates from the high degree of backbone planarity and molecular order, which contributes to its high charge carrier mobility. In addition, the highly crystalline structure of DPP‐MeDTP is well maintained upon doping, while the crystalline order of the other polymers decreases significantly upon doping. The findings of this work not only provide insights into the design of DTP‐based conjugated polymers for thermoelectric use but also demonstrate the significance of a high degree of molecular order and structural robustness upon doping to achieve high thermoelectric performance.
Chemically Recyclable CO2‐Based Solid Polyesters with Facile Property Tunability
Authors: Lou Yongjia , Xu Jialin , Xu Luyan , Chen Zhuo , Lin Bo‐Lin
Published: May 2022

Synthesizing chemically recyclable solid polymeric materials is a significant strategy to potentially achieve carbon neutral production of new polymers and alleviate plastic pollution, especially when the synthesis is based on CO2 and inexpensive co‐feedstocks available in large scales. Additionally, polymeric materials should have high enough molecular weight to exhibit distinguished properties from low molar mass polymers to serve for a broader range of application scenarios. However, up to now, strategies for developing solid‐state CO2‐based chemically recyclable polyesters with both high molecular weight and facile property tunability are still unprecedented. Herein, a brand‐new synthetic route is developed to synthesize chemically recyclable CO2‐based solid polyesters with high molecular weight (Mn up to 587.7 kg mol−1) and narrow dispersity (Đ < 1.2), which should further broaden the potential application scenarios of new CO2‐based polyesters. Additionally, complete monomer recovery from poly(δLH2) material is also achieved. The preserved terminal alkene groups allow facile property tuning of the polyesters via photo‐initiated thiol‐ene click reactions, enabling more potential utilities and further functionalizations.
A novel algorithm for implementing perturbations in computational simulations of chemical dissolution‐front instability problems within fluid‐saturated porous media
Authors: Zhao Chongbin , Hobbs Bruce , Ord Alison
Published: May 2022

This paper deals with how to implement perturbations in the computational simulations of chemical dissolution‐front instability (CDFI) problems in fluid‐saturated porous media. On the basis of theoretical analysis, it is found that the application of a perturbation to the chemical dissolution front is equivalent to the application of an alternative perturbation to the dimensionless pore‐fluid normal velocity (relative to the planar chemical dissolution front) in the chemical dissolution zone, where the chemical dissolution front is located. This avoids the difficulty to find the spatial coordinates of the chemical dissolution front locations in the computational simulations of CDFI problems. Based on this new finding, a novel algorithm for implementing perturbations in the computational simulations of CDFI problems is proposed. The key point of the proposed algorithm is that the perturbed pore‐fluid normal velocity (relative to the planar chemical dissolution front) is used to directly replace the original pore‐fluid normal velocity (relative to the planar chemical dissolution front) in the related mathematical governing equations (MGEs), so that the proposed algorithm works for the porosity‐velocity‐concentration scheme when it is used to solve CDFI problems in fluid‐saturated porous media. In addition, the related theoretical analysis in this study has answered the previous unanswered question why the application of a perturbation to porosity works in the porosity‐pressure‐concentration scheme but does not work in the porosity‐velocity‐concentration scheme for solving the same CDFI problems in fluid‐saturated porous media. Through solving two illustrative examples with two different distributions of initial porosity, in which one is homogeneous and another is heterogeneous in the chemical dissolution system, the validity and usefulness of the proposed algorithm for implementing perturbations in the computational simulations of CDFI problems have been demonstrated.
Influence of copula approaches on reliability analysis of slope stability using random adaptive finite element limit analysis
Authors: Nguyen Thanh Son , Likitlersuang Suched , Tanapalungkorn Weeradetch , Phan Trung Nghia , Keawsawasvong Suraparb
Published: May 2022

Recently, random field copulas have been deployed to characterise the dependent structures of spatially variable soil parameters. This study expands on this concept by implementing finite element limit analysis (FELA) with adaptive meshing alongside the copula approach to perform reliability assessment of a geotechnical problem. A hypothetical slope with drained and undrained soil conditions was used as an example. First, adaptive FELA was carried out on the hypothetical slope. Second, single and multiple dependency soil parameter structures were represented by several selected copulas (Gaussian, Frank and Clayton). Finally, random adaptive FELA was implemented to explore the effects of copula selection on slope stability and reliability analyses. Results show that considerably different slope failure probabilities are produced by different copula approaches, and that failure probabilities reduce for simulating multiple dependency structures. In addition, failure probability exhibits different tendencies between drained and undrained soil conditions as soil parameter cross‐correlations become stronger. Failure probabilities are also different when performing lower and upper bound (UB) random adaptive FELA with each of the selected copulas.
Numerical optimization of multistage packing pressure profile in plastic injection molding and experimental validation
Authors: Kitayama Satoshi , Matsubayashi Akihiro , Takano Masahiro , Yamazaki Yusuke , Kubo Yoshikazu , Aiba Shuji
Published: May 2022

Plastic injection molding (PIM) is a crucial processing technology for producing lightweight products. Process parameters such as melt temperature, packing pressure, and cooling time directly affect not only the product quality but also the productivity, and they are conventionally adjusted by the trial‐and‐error method. A constant packing pressure is conventionally used, but the multistage packing pressure profile recently attracts attention. However, the packing pressure profile is unknown in advance, and it is difficult to determine it through the trial‐and‐error method. In this paper, the multistage packing pressure profile as well as other process parameters so as to minimize the warpage and cycle time are determined by using computational intelligence and design optimization. It is found from the numerical result that 27% warpage and 50% cycle time reduction can be achieved, compared with ones using reference process parameters. In addition, it is clarified that clamping force can be reduced. This indicates that PIM using the optimal multi‐stage packing pressure profile can produce plastic product with small clamping force that makes the tool life long. Finally, the experiment using PIM machine equipped with servo controller (MS100, Sodick) is carried out to examine the effectiveness of the multistage packing pressure profile.
Stereoselective cycloaddition of biologically active thioindoline with the smallest nanocage in gas phase versus solution via density functional theory
Authors: Asnaashariisfahani Manzarbanou , Azizi Bayan , Poor Heravi Mohammad Reza , Habibzadeh Sepideh , Ebadi Abdol Ghaffar , Ahmadi Sheida
Published: May 2022

A fine speculation of enantioselectivity prior to the expensive experimental endeavors is truly one of the ultimate goals of the computational organic chemists. In this survey, we have predicted stereo specificity for hetero Diels–Alder (DA) cycloaddition of (E)‐3‐benzylidene‐indoline‐2‐thione (I) with C20 to give (Ia) as drug delivery in the gas phase and in solution, at density functional theory (DFT)–self‐consistent reaction field (SCRF). The enthalpy difference between liquid (l) and gas (g) phases (∆Hl‐g), as well as activation energy (Eexo≠, Eendo≠) of Ia cycloadduct, appears proportional to the dielectric constant of solvent (ε). In contrast to the above trends, kinetic stability based on ∆EL‐H of Ia, develops in opposite to that of ε. The more stability of Ia is attributed to its H―bonding, and dipole–dipole interaction in water. The energy barrier of exo transition states (TS) is low; hence, cycloaddition is recommended to be of synthetically interest for preparation of asymmetric nano compound. Moreover, the π‐π aromatic stacking among the substituted phenyl ring and C20 (πsubstituted phenyl ring ↔ πC20) has significant effect on destabilization of endo TS. This DA reaction have polar nature according to one‐step mechanism, that comprises an initial hetero‐DA reaction yielding Ia, which experiences a subsequent [3,3] sigmatropic shift to yield the expected formal cycloadduct. This is a consequence of more polar nature of reaction, due to lower nucleophilicity (N), higher electrophilicity (ω), higher maximum electronic charge (ΔNmax), more polarity (μ), and more global electron density transfer (GEDT) of Ia in polar solvents (especially in water) in comparison to gas phase. This polar character is given by the electrophilic character of the C20 dienophile (ω = 5.29 eV) and nucleophilic character of the 1,3‐diene molecule (I) (N = 3.70 eV). Additionally, molecular mechanism of the considered reaction is substantially different from the DA reactions between simple 1,3‐diene and dienophiles.
Exogenous genistein enhances soybean resistance to Xanthomonas axonopodis pv. glycines
Authors: Zhang Yun‐Jiao , Pang Yi‐Bo , Wang Xin‐Yi , Jiang Yong‐Hui , Herrera‐Balandrano Daniela D. , Jin Yan , Wang Su‐Yan , Laborda Pedro
Published: May 2022

BACKGROUND

Xanthomonas axonopodis pv. glycines (Xag) is the causal agent of bacterial pustule disease and results in enormous losses in soybean production. Although isoflavones are known to be involved in soybean resistance against pathogen infection, the effects of exogenous isoflavones on soybean plants remain unexplored.

RESULTS

Irrigation of soybean plants with isoflavone genistein inhibited plant growth for short periods, probably by inhibiting the tyrosine (brassinosteroids) kinase pathway, and increased disease resistance against Xag. The number of lesions was reduced by 59%–63% when applying 50 μg ml−1 genistein. The effects on disease resistance were observed for 15 days after treatment. Genistein also enhanced the disease resistance of soybean against the fungal pathogen Sclerotinia sclerotiorum. Exogenous genistein increased antioxidant capacity, decreased H2O2 level and promoted the accumulation of phenolics in Xag‐infected soybean leaves. Exogenous genistein reduced the amounts of endogenous daidzein, genistein and glycitein and increased the concentration of genistin, which was found to show strong antibacterial activity against the pathogen and to reduce the expression of virulence factor yapH, and flagella formation gene flgK. The expression of several soybean defense genes, such as chalcone isomerase, glutathione S‐transferase and 1‐aminocyclopropane‐1‐carboxylate oxidase 1, was upregulated after genistein treatment.

CONCLUSIONS

The effects of exogenous genistein on soybean plants were examined for the first time, revealing new insights into the roles of isoflavones in soybean defense and demonstrating that irrigation with genistein can be a suitable method to induce disease resistance in soybean plants. © 2022 Society of Chemical Industry.
Population pharmacokinetic model for once‐daily intravenous busulfan in pediatric subjects describing time‐associated clearance
Authors: Lawson Rachael , Staatz Christine E. , Fraser Christopher J. , Ramachandran Shanti , Teague Lochie , Mitchell Richard , O'Brien Tracey , Hennig Stefanie
Published: May 2022

This study aimed to characterize the population pharmacokinetics (PK) of busulfan focusing on how busulfan clearance (CL) changes over time during once‐daily administration and assess different methods for measuring busulfan exposure and the ability to achieve target cumulative exposure under different dosing adjustment scenarios in pediatric stem cell transplantation recipients. Daily serial blood sampling was performed and concentration‐time data were analyzed using a nonlinear mixed‐effects approach. The developed PK model was used to assess achievement of target exposure under six dose‐adjustment scenarios based on simulations performed in RStudio (RxODE package)®. A total of 2491 busulfan plasma concentration–time measurements were collected from 95 patients characterizing 379 dosing days. A two‐compartment model with time‐associated CL best described the data with a typical CL of 14.5 L/h for an adult male with 62 kg normal fat mass (NFM; equivalent to 70 kg total body weight), typical volume of distribution central compartment (V1) of 40.6 L/59 kg NFM (equivalent to 70 kg total body weight), and typical volume of distribution peripheral compartment of 3.57 L/62 kg NFM. Model interindividual variability in CL and V1 was 14.7% and 34.9%, respectively, and interoccasional variability in CL was 6.6%. Patient size described by NFM, a maturation component, and time since start of treatment significantly influenced CL. Simulations demonstrated that using model‐based exposure estimates with each dose, and either a proportional dose‐adjustment calculation or model‐based calculated individual CL estimates to support dose adjustments, increased proportion of subjects attaining cumulative exposure within 5% of target compared with using noncompartmental analysis (100% vs. 0%). A time‐associated reduction in CL during once‐daily busulfan treatment was described.
An unusual tracheal foreign body residing for 15 years: A case report and review of literature
Authors: Sapkota Ranjan , Sharma Aakriti , Bastola Priska
Published: May 2022

Airway foreign bodies are common in children, and usually present as emergencies. However, they may sometimes present late, due to a number of reasons. Chronic lodgement of foreign bodies in trachea is rarer than that in bronchial tree. Flexible and rigid bronchoscopies have revolutionized the management of foreign bodies at large. Here, we report a successful bronchoscopic management of an unusual foreign body residing in the trachea of a patient for 15 years.
Hierarchical robust control for variable‐pitch wind turbine with actuator faults
Authors: Ameli Sina , Anubi Olugbenga Moses
Published: May 2022

In this brief, we develop a fault tolerant control (FTC) using a hierarchical‐robust methodology with guaranteed stability for a wind turbine (WT), which is subject to an exogenous input and an actuator fault. The high‐level control is designed to robustly compensate for the nonlinearities, uncertainty, and disturbance in the system. The low‐level control is designed to robustly automatically allocate control authority among redundant actuators mitigating an actuator fault. At the low‐level, the robust control problem is transformed into an equivalent optimal control problem. Finally, the developed FTC is validated using a comprehensive simulation study on a 5 MW variable‐pitch WT model given in the Fatigue, Aerodynamics, Structures, and Turbulence (FAST) simulator provided by the U.S. National Renewable Energy Laboratory (NREL). The results show that the developed FTC retains robust performance in the presence of wind disturbance and a time‐varying actuator fault.
A New Inert Gas Delivery Design for Improved Shielding of Ladle Shroud–Collector Nozzle (LS–CN) Assembly: Modeling, Design, and Industrial‐Scale Validations
Authors: Mukherjee Suvam , Mazumdar Dipak
Published: May 2022

Argon injection in ladle shrouds is customarily practiced during the teeming of liquid steel from ladle to tundish to minimize air ingression and thereby restrict atmospheric oxidation of steel melt. Despite such practices, nitrogen pickup results in the tundish, implying inadequate shielding of ladle shroud–collector nozzle (LS–CN) joint. Accordingly, the efficacy of different argon injection designs in shrouds is evaluated in the present study, and thereby, a novel argon injection arrangement, embodying a twin, tangential gas discharge system, developed as a curative step to ensure maximum inertization of the LS–CN assembly. Numerical prediction of argon flow and distribution around the LS–CN assembly is accompanied by a homogeneous, non‐isothermal, two‐component turbulent flow model embodied in ANSYS Fluent. These, supported adequately by water modeling results, indicated that inertization of LS–CN assembly is considerably improved with the proposed design at argon flowrates typically practiced in industries (10 Nlit min−1). To substantiate laboratory findings, a plant‐scale investigation is carried out, wherein shrouds with a new gas delivery design are fabricated and deployed in continuous bloom casting operation in a special steel plant. Industrial trials confirm the superiority of the new design over existing ones and demonstrate a 50% reduction in nitrogen pickup, during teeming, under identical operating conditions.
Using ALLIGATORs to Capture Circadian Bioluminescence
Authors: Zeng Aiwei , O’Neill John S.
Published: May 2022

Luciferases are a popular tool in circadian biology research as longitudinal reporters of gene expression. Here, we describe a short updated protocol for the use of an Automated Longitudinal Luciferase Imaging Gas and Temperature-Optimized Recorder (ALLIGATOR) to record cellular bioluminescence over many days. The ALLIGATOR has superior capacity and flexibility compared with traditional luminometers that employ photomultiplier tubes (PMTs), with high-throughput capability and spatial resolution. It can be readily adapted to a wide variety of applications, such as different sample types and plate sizes, under a wide range of physiologically relevant conditions.
Entanglement phase structure of a holographic BCFT in a black hole background
Authors: Geng Hao , Karch Andreas , Perez-Pardavila Carlos , Raju Suvrat , Randall Lisa , Riojas Marcos , Shashi Sanjit
Published: May 2022

Abstract

We compute holographic entanglement entropy for subregions of a BCFT thermal state living on a nongravitating black hole background. The system we consider is doubly holographic and dual to an eternal black string with an embedded Karch-Randall brane that is parameterized by its angle. Entanglement islands are conventionally expected to emerge at late times to preserve unitarity at finite temperature, but recent calculations at zero temperature have shown such islands do not exist when the brane lies below a critical angle. When working at finite temperature in the context of a black string, we find that islands exist even when the brane lies below the critical angle. We note that although these islands exist when they are needed to preserve unitarity, they are restricted to a finite connected region on the brane which we call the atoll. Depending on two parameters — the size of the subregion and the brane angle — the entanglement entropy either remains constant in time or follows a Page curve. We discuss this rich phase structure in the context of bulk reconstruction.
Gravitational causality and the self-stress of photons
Authors: Bellazzini Brando , Isabella Giulia , Lewandowski Matthew , Sgarlata Francesco
Published: May 2022

Abstract

We study causality in gravitational systems beyond the classical limit. Using on-shell methods, we consider the 1-loop corrections from charged particles to the photon energy-momentum tensor — the self-stress — that controls the quantum interaction between two on-shell photons and one off-shell graviton. The self-stress determines in turn the phase shift and time delay in the scattering of photons against a spectator particle of any spin in the eikonal regime. We show that the sign of the β-function associated to the running gauge coupling is related to the sign of time delay at small impact parameter. Our results show that, at first post-Minkowskian order, asymptotic causality, where the time delay experienced by any particle must be positive, is respected quantum mechanically. Contrasted with asymptotic causality, we explore a local notion of causality, where the time delay is longer than the one of gravitons, which is seemingly violated by quantum effects.
Two-loop tensor integral coefficients in OpenLoops
Authors: Pozzorini Stefano , Schär Natalie , Zoller Max F.
Published: May 2022

Abstract

We present a new and fully general algorithm for the automated construction of the integrands of two-loop scattering amplitudes. This is achieved through a generalisation of the open-loops method to two loops. The core of the algorithm consists of a numerical recursion, where the various building blocks of two-loop diagrams are connected to each other through process-independent operations that depend only on the Feynman rules of the model at hand. This recursion is implemented in terms of tensor coefficients that encode the polynomial dependence of loop numerators on the two independent loop momenta. The resulting coefficients are ready to be combined with corresponding tensor integrals to form scattering probability densities at two loops. To optimise CPU efficiency we have compared several algorithmic options identifying one that outperforms naive solutions by two orders of magnitude. This new algorithm is implemented in the OpenLoops framework in a fully automated way for two-loop QED and QCD corrections to any Standard Model process. The technical performance is discussed in detail for several 2 → 2 and 2 → 3 processes with up to order 105 two-loop diagrams. We find that the CPU cost scales linearly with the number of two-loop diagrams and is comparable to the cost of corresponding real-virtual ingredients in a NNLO calculation. This new algorithm constitutes a key building block for the construction of an automated generator of scattering amplitudes at two loops.
Haftung für chronische Arbeitszeitverstöße in der Medizin – wann drohen Bußgelder und Freiheitsstrafen?
Authors: Struck J. P. , Neugebauer F. , Stahl L. , König J. , Braun M. , Westphal J.
Published: May 2022

Vor dem Hintergrund der Tarifvertragsänderungen, für die kommunalen Kliniken in der Fassung vom 1. Januar 2021, für die Universitätskliniken in der Fassung vom 7. März 2020, beschäftigt sich der vorliegende Artikel mit den rechtlichen Konsequenzen chronischer Verstöße gegen das Arbeitszeitgesetz in der Medizin, insbesondere aber in chirurgischen Fächern wie der Urologie. Er beinhaltet eine Übersicht über geltendes Recht und Sanktionierungen von Verstößen und beleuchtet Zuständigkeiten sowie Ausnahmeregelungen. Es gilt, die Verteilung der Zuständigkeiten hinsichtlich der Arbeitszeiten im betroffenen Betrieb zu klären, um Geldstrafen und im schlimmsten Falle Freiheitsstrafen zu vermeiden. Zudem sollte klar sein, wer im konkreten Fall von beharrlichen Arbeitszeitverstößen haftet. Bei der Umstellung von Dienstmodellen gilt es zu berücksichtigen, dass es dadurch zu einer erheblichen Verschlechterung der ärztlichen Weiterbildungsmöglichkeiten bzw. Ausbildung kommen kann, so dass auf Dauer die Vereinbarkeit von arbeitszeitgerechter Weiterbildung nur mit ausreichender personeller Ausstattung der Kliniken zu stemmen scheint. Dies steht z. T. diametral zu ökonomischen Interessen im Gesundheitswesen und stellt damit ein schier unlösbares Dilemma dar. Hier bedarf es aus der Sicht des Arbeitskreises in naher Zukunft struktureller Änderungen im Fallpauschalen (DRG) basierten, stationären Sektor.
A principle-based approach to AI: the case for European Union and Italy
Authors: Corea Francesco , Fossa Fabio , Loreggia Andrea , Quintarelli Stefano , Sapienza Salvatore
Published: May 2022

As Artificial Intelligence (AI) becomes more and more pervasive in our everyday life, new questions arise about its ethical and social impacts. Such issues concern all stakeholders involved in or committed to the design, implementation, deployment, and use of the technology. The present document addresses these preoccupations by introducing and discussing a set of practical obligations and recommendations for the development of applications and systems based on AI techniques. With this work we hope to contribute to spreading awareness on the many social challenges posed by AI and encouraging the establishment of good practices throughout the relevant social areas. As points of novelty, the paper elaborates on an integrated view that combines both human rights and ethical concepts to reap the benefits of the two approaches. Moreover, it proposes innovative recommendations, such as those on redress and governance, which add further insight to the debate. Finally, it incorporates a specific focus on the Italian Constitution, thus offering an example of how core legislations of Member States might contribute to further specify and enrich the EU normative framework on AI.
Continuity of envelopes of unbounded plurisubharmonic functions
Authors: Nilsson Mårten
Published: May 2022

On bounded B-regular domains, we study envelopes of plurisubharmonic functions bounded from above by a function $$\phi $$
ϕ
which is continuous in the extended reals on the closure of the domain. For $$\phi $$
ϕ
satisfying certain additional criteria limiting its behavior at the singularities, we establish a set where the Perron–Bremermann envelope $$P \phi $$

P
ϕ

is guaranteed to be continuous. This result is a generalization of a classic result in pluripotential theory due to J. B. Walsh. As an application, we show that the complex Monge–Ampère equation $$\begin{aligned} (dd^cu)^n = \mu \end{aligned}$$

(
d

d
c

u
)

n

=
μ

being uniquely solvable for continuous boundary data implies that it is also uniquely solvable for a class of boundary values continuous in the extended reals and unbounded from above.
Applying pharmacokinetic/pharmacodynamic measurements for linezolid in critically ill patients: optimizing efficacy and reducing resistance occurrence
Authors: El-Gaml Rasha M. , El-Khodary Noha M. , Abozahra Rania R. , El-Tayar Ayman A. , El-Masry Soha M.
Published: May 2022

Purpose

Linezolid (LZD) levels are frequently insufficient in intensive care unit (ICU) patients receiving standard dose, which is predictive of a poor prognosis. Alternative dosing regimens are suggested to address these insufficient levels, which are substantial factors contributing to the emergence of multidrug-resistant bacteria, resulting in increased morbidity and mortality among people who are critically ill.

Methods

Forty-eight patients admitted to the intensive care unit were enrolled in an open-label, prospective, randomized study and assigned to one of three LZD administration modes: intermittent groupI (GpI) (600 mg/12 h), continuous infusion groupII (GpII) (1200 mg/24 h) or continuous infusion with loading dose groupIII (GpIII) (on Day 1, 300 mg intravenously plus 900 mg continuous infusion, followed by 1200 mg/24 h on Day 2). We evaluated serum levels of LZD using a validated ultra-performance liquid chromatography (UPLC) technique.

Results

Time spent with a drug concentration more than 85% over the minimum inhibitory concentration (T > MIC) was substantially more common in GpII and III than in GpI (P < 0.01). AUC/MIC values greater than 80 were obtained more frequently with continuous infusion GpIII and GpII than with intermittent infusion GpI, at 62.5%, 37.5% and 25%, respectively (P < 0.01). In GpI, the mortality rate was significantly higher than in the other groups.

Conclusion

In critically ill patients, continuous infusion with a loading dose (GpIII) is obviously superior to continuous infusion without a loading dose (GpII) or intermittent infusion (GpI) for infection therapy. Additionally, it might limit fluctuations in plasma concentrations, which may help overcome LZD resistance.
Thermo-hygro-mechanically coupled modelling of wood including two-phase moisture diffusion for transient simulation of wooden structures at mechanical and climatic loads
Authors: Stöcklein Josef , Kaliske Michael
Published: May 2022

A model to predict the thermo-hygro-mechanical behaviour of wood is introduced. The description of the transport processes of moisture and heat are combined with a model for the mechanical response. Moisture transport is represented by a two-phase multi-Fickian approach, considering bound water and water vapour. For the mechanical response, a moisture- and temperature-dependent, orthotropic, elastic material formulation is used. The theoretical basis of the model and the numerical implementation of the monolithic solution into a Finite Element framework are discussed as well as its verification and validation. With this model at hand, arbitrary wooden structures can be simulated in a transient manner subjected to climatic and mechanical loads. In the contribution, the approach is applied to the analysis of a panel painting by L. Cranach the Elder.
50 Jahre universitärer Informatik-Studiengang an der TU Dresden aus der Sicht von Zeitzeugen in einem Zeitstrahl
Authors: Demuth Birgit , Rohde Frank , Aßmann Uwe
Published: May 2022

Im Jahr 2019 haben deutsche Universitäten das Jubiläum einer 50-jährigen Informatikausbildung gefeiert. Die TU Dresden blickt dabei seit 1969 als erste Universität auf Erfahrungen in beiden deutschen Staaten zurück. Während die historische Entwicklung in der Informatikausbildung für die BRD gut dokumentiert ist, besteht in der Dokumentation durch dasInformatik Spektrumfür die DDR eine Lücke. Die Informatikausbildung in der DDR befand sich seit ihren Anfängen auf Augenhöhe mit den Entwicklungen in der BRD. Im vorliegenden Artikel wird die historische Entwicklung des Informatik-Studienganges an der TU Dresden unter Berücksichtigung der Entstehungs- und Entwicklungsphase in der DDR und der Wendezeit bis zur heutigen Fakultät Informatik dargestellt. Aus Anlass des 50-Jahre-Jubiläums im Jahr 2019 wurde die historische Entwicklung in einem webbasierten Zeitstrahl dokumentiert und mit Interviews von Zeitzeugen ergänzt. Dabei lag der Schwerpunkt auf der Lehre einschließlich der Einheit von Lehre und Forschung.
Using deep learning to safely exclude lesions with only ultrafast breast MRI to shorten acquisition and reading time
Authors: Jing Xueping , Wielema Mirjam , Cornelissen Ludo J. , van Gent Margo , Iwema Willie M. , Zheng Sunyi , Sijens Paul E. , Oudkerk Matthijs , Dorrius Monique D. , van Ooijen Peter M.A.
Published: May 2022

Objectives

To investigate the feasibility of automatically identifying normal scans in ultrafast breast MRI with artificial intelligence (AI) to increase efficiency and reduce workload.

Methods

In this retrospective analysis, 837 breast MRI examinations performed on 438 women from April 2016 to October 2019 were included. The left and right breasts in each examination were labelled normal (without suspicious lesions) or abnormal (with suspicious lesions) based on final interpretation. Maximum intensity projection (MIP) images of each breast were then used to train a deep learning model. A high sensitivity threshold was calculated based on the detection trade - off (DET) curve on the validation set. The performance of the model was evaluated by receiver operating characteristic analysis of the independent test set. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) with the high sensitivity threshold were calculated.

Results

The independent test set consisted of 178 examinations of 149 patients (mean age, 44 years ± 14 [standard deviation]). The trained model achieved an AUC of 0.81 (95% CI: 0.75–0.88) on the independent test set. Applying a threshold of 0.25 yielded a sensitivity of 98% (95% CI: 90%; 100%), an NPV of 98% (95% CI: 89%; 100%), a workload reduction of 15.7%, and a scan time reduction of 16.6%.

Conclusion

This deep learning model has a high potential to help identify normal scans in ultrafast breast MRI and thereby reduce radiologists’ workload and scan time.

Key Points

• Deep learning in TWIST may eliminate the necessity of additional sequences for identifying normal breasts during MRI screening.

• Workload and scanning time reductions of 15.7% and 16.6%, respectively, could be achieved with the cost of 1 (1 of 55) false negative prediction.
Determining voluntary activation in synergistic muscles: a novel mechanomyographic approach
Authors: Cè Emiliano , Coratella Giuseppe , Doria Christian , Borrelli Marta , Rampichini Susanna , Limonta Eloisa , Longo Stefano , Esposito Fabio
Published: May 2022

Purpose

Drawing on correlations between the mechanomyographic (MMG) and the force signal, we devised a novel approach based on MMG signal analysis to detect voluntary activation (VA) of the synergistic superficial heads of the quadriceps muscle. We hypothesized that, after a fatiguing exercise, the changes in the evoked MMG signal of each quadriceps head would correlate with the changes in the level of VA in the whole quadriceps.

Methods

Twenty-five men underwent a unilateral single-leg quadriceps exercise to failure. Before and after exercise, VA was assessed by interpolated-twitch-technique via nerve stimulation during and after maximum voluntary contraction (MVC). The force and MMG signal were recorded from vastus lateralis, vastus medialis, and rectus femoris. The MMG peak-to-peak was calculated and the voluntary activation index (VAMMG), defined as the superimposed/potentiated MMG peak-to-peak ratio, was determined from the MMG signal for each head.

Results

VAMMG presented a very high intraclass correlation coefficient (0.981–0.998) and sensitivity (MDC95%: 0.42–6.97%). MVC and VA were decreased after exercise in both the exercising [MVC:−17(5)%, ES −0.92; VA: −7(3)%, ES −1.90] and the contralateral limb [MVC: −9(4)%, ES −0.48; VA: −4(1)%, ES −1.51]. VAMMG was decreased in both the exercising [~ −9(6)%, ES −1.77] and contralateral limb [~ −3(2)%, ES −0.57], with a greater decrease in VAMMG noted only in the vastus medialis of the exercising limb. Moderate-to-very high correlations were found between VAMMG and VA (R-range: 0.503–0.886) before and after exercise.

Conclusion

VAMMG may be implemented to assess VA and provide further information when multiple synergistic muscle heads are involved in fatiguing exercises.
Experimentally manipulated food availability affects offspring quality but not quantity in zebra finch meso-populations
Authors: Gerritsma Yoran H. , Driessen Merijn M. G. , Tangili Marianthi , de Boer Sietse F. , Verhulst Simon
Published: May 2022

Food availability modulates survival, reproduction and thereby population size. In addition to direct effects, food availability has indirect effects through density of conspecifics and predators. We tested the prediction that food availability in isolation affects reproductive success by experimentally manipulating food availability continuously for 3 years in zebra finches (Taeniopygia guttata) housed in outdoor aviaries. To this end, we applied a technique that mimics natural variation in food availability: increasing the effort required per food reward without affecting diet. Lower food availability resulted in a slight delay of start of laying and fewer clutches per season, but did not affect clutch size or number of offspring reared per annum. However, increasing foraging costs substantially reduced offspring growth. Thus, food availability in isolation did not impact the quantity of offspring reared, at the expense of offspring quality. Growth declined strongly with brood size, and we interpret the lack of response with respect to offspring number as an adaptation to environments with low predictability, at the time of egg laying, of food availability during the period of peak food demand, typically weeks later. Manipulated natal brood size of the parents did not affect reproductive success. Individuals that were more successful reproducers were more likely to survive to the next breeding season, as frequently found in natural populations. We conclude that the causal mechanisms underlying associations between food availability and reproductive success in natural conditions may be more complex than usually assumed. Experiments in semi-natural meso-populations can contribute to further unravelling these mechanisms.
Using machine learning to predict individual patient toxicities from cancer treatments
Authors: Cole Katherine Marie , Clemons Mark , McGee Sharon , Alzahrani Mashari , Larocque Gail , MacDonald Fiona , Liu Michelle , Pond Gregory R. , Mosquera Lucy , Vandermeer Lisa , Hutton Brian , Piper Ardelle , Fernandes Ricardo , Emam Khaled El
Published: May 2022

Purpose

Machine learning (ML) is a powerful tool for interrogating datasets and learning relationships between multiple variables. We utilized a ML model to identify those early breast cancer (EBC) patients at highest risk of developing severe vasomotor symptoms (VMS).

Methods

A gradient boosted decision model utilizing cross-sectional survey data from 360 EBC patients was created. Seventeen patient- and treatment-specific variables were considered in the model. The outcome variable was based on the Hot Flush Night Sweats (HFNS) Problem Rating Score, and individual scores were dichotomized around the median to indicate individuals with high and low problem scores. Model accuracy was assessed using the area under the receiver operating curve, and conditional partial dependence plots were constructed to illustrate relationships between variables and the outcome of interest.

Results

The model area under the ROC curve was 0.731 (SD 0.074). The most important variables in the model were as follows: the number of hot flashes per week, age, the prescription, or use of drug interventions to manage VMS, whether patients were asked about VMS in routine follow-up visits, and the presence or absence of changes to breast cancer treatments due to VMS. A threshold of 17 hot flashes per week was identified as being more predictive of severe VMS. Patients between the ages of 49 and 63 were more likely to report severe symptoms.

Conclusion

Machine learning is a unique tool for predicting severe VMS. The use of ML to assess other treatment-related toxicities and their management requires further study.
Patient-caregiver communication concordance in cancer—refinement of the Cancer Communication Assessment Tool in an Australian sample
Authors: Michael Natasha , Gorelik Alex , Georgousopoulou Ekavi , Sulistio Merlina , Tee Patrick , Hauser Katherine , Kissane David
Published: May 2022

Purpose

The objective of this study was to expand the international psychometric validation of the Cancer Communication Assessment Tool for Patients and Families (CCAT-PF) within a sample of Australian cancer patients.

Methods

Survey data from 181 cancer patient-caregiver dyads ≥ 18 years of age with solid or haematological cancers were analysed (85.4% response rate). Spearman’s rho was used to examine the correlation between CCAT-P and CCAT-F scores and weighted kappa the agreement between them. Exploratory factor analysis using scree plot and Kaiser-Guttman criteria was conducted to evaluate the scale structure. Cronbach’s α and Pearson correlation coefficients were used to measure internal consistency and concurrent validity respectively.

Results

Mean scores were the following: CCAT-P 46.2 (9.8), CCAT-F 45.7 (9.4), and CCAT-PF 24.1 (8.0). We confirmed the poor concordance between patient and caregiver reporting of items in the CCAT-PF, with all but two items having weighted kappa values < 0.20 and Spearman’s rho < 0.19. We derived a three-factor solution, disclosure, limitation of treatment, and treatment decision making, with reliability ranging from Cronbach’s α = 0.43–0.53. The CCAT-P and CCAT-F showed strong correlations with preparation for decision-making (CCAT-P: r = 0.0.92; CCATF: r = 0.0.93) but were weakly associated with patient/caregiver distress related with having difficult conversations on future care planning.

Conclusion

Preliminary validation of the CCAT-PF in the Australian setting has shown some similar psychometric properties to previously published studies, further supporting its potential utility as a tool to assess patient-caregiver dyadic communication.

Trial registration

ACTRN12620001035910 12/10/2020 retrospectively registered.