bluuebunny/crossref_metadata_2025 huggingface dataset:
Maternal and neonatal outcomes in pregnancies conceived after preimplantation genetic testing
Authors: Gulersen Moti , Peyser Alexandra , Ferraro Amanda , Goldman Randi , Mullin Christine , Li Xueying , Krantz David , Bornstein Eran , Rochelson Burton
Published: March 2021

Objective

To determine whether preimplantation genetic testing (PGT) is associated with an increase in adverse maternal or neonatal outcomes in singleton and twin live births conceived via in vitro fertilization (IVF).

Method

Retrospective cohort of live births resulting from IVF within a university health system between January 2014 and August 2019. Adverse maternal outcomes (e.g., hypertensive disorders of pregnancy, abnormal placentation, and preterm birth), and adverse neonatal outcomes were compared in singleton and twin pregnancies conceived after transfer of one or two PGT‐screened euploid embryos versus untested embryos in separate analyses. Multivariate backwards‐stepwise logistic regression was used to adjust for potential confounders.

Results

Of 1160 live births, 539 (46.5%) resulted from PGT‐screened embryos, 1015 (87.5%) were singletons, and 145 (12.5%) were twins. After adjusting for potential confounders, there were no significant differences between the two groups with respect to hypertensive disorders of pregnancy, fetal growth restriction, preterm birth, and adverse neonatal outcomes in both analyses, as well as abnormal placentation for singletons.

Conclusion

Our data suggest that IVF with PGT is not associated with an increased risk of adverse maternal or neonatal outcomes compared to IVF without PGT. Further research utilizing larger cohorts are needed before drawing definitive conclusions.
Opioid use and social disadvantage in patients with chronic musculoskeletal pain
Authors: Cheng Abby L. , Brady Brian K. , Bradley Ethan C. , Calfee Ryan P. , Klesges Lisa M. , Colditz Graham A. , Prather Heidi
Published: March 2021

Background

Historically, marginalized patients were prescribed less opioid medication than affluent, white patients. However, because of persistent differential access to nonopioid pain treatments, this direction of disparity in opioid prescribing may have reversed.

Objective

To compare social disadvantage and health in patients with chronic pain who were managed with versus without chronic opioid therapy. It was hypothesized that patients routinely prescribed opioids would be more likely to live in socially disadvantaged communities and report worse health.

Design

Cross‐sectional analysis of a retrospective cohort defined from medical records from 2000 to 2019.

Setting

Single tertiary safety net medical center.

Patients

Adult patients with chronic musculoskeletal pain who were managed longitudinally by a physiatric group practice from at least 2011 to 2015 (n = 1173), subgrouped by chronic (≥4 years) adherent opioid usage (n = 356) versus no chronic opioid usage (n = 817).

Intervention

Not applicable.

Main Outcome Measures

The primary outcome was the unadjusted between‐group difference in social disadvantage, defined by living in the worst national quartile of the Area Deprivation Index (ADI). An adjusted effect size was also calculated using logistic regression, with age, sex, race, and Patient‐Reported Outcomes Measurement Information System (PROMIS) Pain Interference and Physical Function scores as covariates. Secondary outcomes included adjusted differences in health by chronic opioid use (measured by PROMIS).

Results

Patients managed with chronic opioid therapy were more likely to live in a zip code within the most socially disadvantaged national quartile (34.9%; 95% confidence interval [CI] 29.9–39.9%; vs. 24.9%; 95% CI 21.9–28.0%; P < .001), and social disadvantage was independently associated with chronic opioid use (odds ratio [OR] 1.01 per ADI percentile [1.01–1.02]). Opioid use was also associated with meaningfully worse PROMIS Depression (3.8 points [2.4–5.1]), Anxiety (3.0 [1.4–4.5]), and Pain Interference (2.6 [1.7–3.5]) scores.

Conclusions

Patients prescribed chronic opioid treatment were more likely to live in socially disadvantaged neighborhoods, and chronic opioid use was independently associated with worse behavioral health. Improving access to multidisciplinary, nonopioid treatments for chronic pain may be key to successfully overcoming the opioid crisis.
Exploring, harnessing and conserving marine genetic resources towards a sustainable seaweed aquaculture
Authors: Brakel Janina , Sibonga Rema C. , Dumilag Richard V. , Montalescot Valeria , Campbell Iona , Cottier‐Cook Elizabeth J. , Ward Georgia , Le Masson Virginie , Liu Tao , Msuya Flower E. , Brodie Juliet , Lim Phaik‐Eem , Gachon Claire M. M.
Published: March 2021

Societal Impact Statement

Seaweed cultivation is the fastest‐growing aquaculture sector, with a demonstrable potential to drive development in some of the poorest coastal populations worldwide. However, sustainable exploitation, fair access and equitable benefits from marine genetic resources, such as seaweeds have yet to be fully realised. Patchy fundamental knowledge on the genetic diversity and metabolic potential of algae limits their exploitation; scant practical skills and low investment in breeding restricts germplasm availability and the Nagoya protocol has only partially remediated insufficient governance. Further developments and the addressing of knowledge gaps in relation to biosecurity, breeders’ rights and conservation of genetic resources are needed for progress.

We review how seaweed genetic resources are currently used in aquaculture, in relation to the diversification and rapidly increasing use of marine resources. Using a revealing case‐study, we summarise the potential for positive societal change, underpinned by the cultivation of eucheumatoid carrageenophytes (species of the red algal genera Eucheuma and Kappaphycus), an activity which has been successfully initiated in many tropical countries to support their economic development. We also review the challenges currently faced by this industry and identify potential threats to the seaweed cultivation sector. Accordingly, we suggest new directions to support the continued development of an economically resilient and environmentally sustainable industry based on the utilisation of genetic resources.
Reliability and validity of physical fitness tests in people with mental disorders: A systematic review and meta‐analysis
Authors: de Oliveira Tavares Vagner Deuel , Vancampfort Davy , Hallgren Mats , Heissel Andreas , Chaparro Camilo German Alberto Pérez , Solmi Marco , Tempest Gavin D. , de Oliveira Neto Leônidas , Galvão‐Coelho Nicole Leite , Firth Joseph , Schuch Felipe Barreto
Published: March 2021

Background

Several tests are available to assess the different components of physical fitness, including cardiorespiratory fitness, muscular strength, and flexibility. However, the reliability and validity of physical fitness tests in people with mental disorders has not been meta‐analyzed.

Aims

To examine the reliability, concurrent, and convergent validity of physical fitness tests in people with mental disorders.

Methods

Studies evaluating the reliability, concurrent, and convergent validity of physical fitness tests in people with mental disorders were searched from major databases until January 20, 2020. Random‐effects meta‐analyses were performed pooling (1) reliability: test–retest correlations at two‐time points, (2) convergent validity between submaximal tests and maximal protocols, or (3) concurrent validity between two submaximal tests. Associations are presented usingrvalues and 95% confidence intervals. Methodological quality was assessed using the Quality Appraisal of Reliability Studies and the Critical Appraisal Tool.

Results

A total of 11 studies (N = 504; 34% females) were included. Reliability of the fitness tests, producedrvalues ranging from moderate (balance test‐EUROFIT; [r = 0.75 (0.60–0.85);p = 0.0001]) to very strong (explosive leg power EUROFIT; [r = 0.96 (0.93–0.97);p = 0.0001]). Convergent validity between the 6‐min walk test (6MWT) and submaximal cardiorespiratory tests was moderate (0.57 [0.26–0.77];p = 0.0001). Concurrent validity between the 2‐min walk test and 6MWT (r = 0.86 [0.39–0.97];p = 0.0004) was strong.

Conclusion

The present study demonstrates that physical fitness tests are reliable and valid in people with mental disorders.
Dissipation kinetics and processing behavior of boscalid and pyraclostrobin in greenhouse dill plant (Anethum graveolens L.) and soil
Authors: Jankowska Magdalena , Kaczyński Piotr , Łozowicka Bożena
Published: March 2021

BACKGROUND

Determining the environmental behavior and fate of chemical compounds during technological processing of plants is a task of great significance nowadays. However, the current knowledge is still incomplete for unique herbal matrices belonging to minor crops. The research in this article presents, for the first time, the dissipation kinetics and processing behavior of carboxamide boscalid (BOS) and stobilurin pyraclostrobin (PYR) fungicides during glasshouse dill (Anethum graveolens L.) cultivation.

RESULTS

The half‐lives (t1/2) of BOS and PYR after application at the recommended and double dosage were in the range: 1.62–2.01 days in plant and 2.08–4.85 days in soil, respectively. The processing behavior in dill was estimated after washing, hot air drying and drying in sunlight without/with pretreatment. Processing factors (PFs) were above 1 after drying (PF = 1.24–1.39 hot air; PF = 1.15–1.28 sunlight) and below this value when the washing step was applied (PF = 0.31–0.42 hot air; PF = 0.21–0.34 sunlight), indicating the highest effectiveness of reduction, up to 73% BOS and 79% PYR.

CONCLUSION

BOS/PYR residues at pre‐harvest intervals after both doses were below European Union (EU) maximum residue limits (MRLs). The highest effectiveness was noted for drying carried out with the washing step, which has a great influence on the concentration of residues in the final product. The findings can supplement PF databases not set for minor crops and can be used to establish MRLs and determine human exposures more accurately in risk assessment studies. © 2021 Society of Chemical Industry.
Pulsed DC Sputtering of Highly c‐Axis AlN Film on Top of Si (111) Substrate
Authors: Iqbal Abid , Walker Glenn , Hold Leonie , Fernandes Alanna , Iacopi Alan , Mohd-Yasin Faisal
Published: March 2021

Herein, pulsed DC sputtering of the AlN film on top of the Si (111) substrate is reported on. First, major articles on the reactive sputtering of AlN film on top of Si (111) substrate that were published in the past 30 years are tabulated. Then, a sputtering recipe to produce a consistent and high‐crystal‐quality (as measured by the full width at half maximum [FWHM] of rocking curve) AlN film across varying substrate temperatures (250–450 °C) and sputtering powers (1200–2400 W) is proposed. In addition, the influence of both parameters to in‐plane stress is demonstrated, in agreement with similar trends that have been reported in the literature for AlN films on other substrates. The best sample is produced at a substrate temperature of 350 °C and sputtering power of 1800 W, resulting in FWHM of rocking curve of 1.84°, surface roughness of 1 nm, and in‐plane stress of +300 MPa. The recipe herein is beneficial for integration of AlN thin film in complementary metal–oxide–semiconductor and micro‐electromechanical system processes.
Radar reflectivity data assimilation method based on background‐dependent hydrometeor retrieval: Comparison with direct assimilation for real cases
Authors: Chen Haiqin , Gao Jidong , Wang Yunheng , Chen Yaodeng , Sun Tao , Carlin Jacob , Zheng Yu
Published: March 2021

Assimilating radar reflectivity into NWP models is one of the keys to improve the accuracy of convective‐scale numerical weather prediction (NWP). There are generally two major branches of research in radar reflectivity assimilation: directly assimilating radar reflectivity, and indirectly assimilating reflectivity, i.e. assimilating hydrometeors retrieved from radar reflectivity. In this study, the indirect assimilation method based on background‐dependent hydrometeor retrievals is compared with the direct assimilation method using frequent data assimilation cycles for five real data cases. The retrieved hydrometeors in the indirect assimilation method are first verified against the hydrometeor types obtained from a polarimetric hydrometeor classification method. It is illustrated that the background‐dependent hydrometeor retrieval method can obtain reasonable model‐equivalent hydrometeors from radar reflectivity. The analysis increments for hydrometeors with both radar data assimilation methods show similar patterns but their magnitudes are different. Both quantitative and qualitative evaluations of forecasted composite reflectivities and accumulated precipitation indicate that the indirect assimilation method predicts the location and intensity of the simulated convection more accurately than the direct method. Furthermore, the indirect assimilation method is more efficient, which is valuable in real‐time applications by helping deliver forecasts quickly and thus helping forecasters make more timely warning decisions.
Atomic charge distribution functions as a tool to analyze electronic structure of molecular and cluster systems
Authors: Gun'ko Vladimir M.
Published: March 2021

A set of the characteristics calculated using any quantum chemical method can be attributed to local electronic structure, which may change for each atom in complex systems. Related average values can give poor characteristics because different atom fractions with different surroundings may have different electronic characteristics poorly corresponding to the average values. The aim of this work is to show that the distribution functions of atomic charges, as well as chemical shifts and molecular orbital energies, can be considered as a set of simple tools for easy analysis of complex systems within the scope of nonlocal characteristics describing whole systems. The approach efficiency and analysis adequacy depend on appropriateness of molecular and cluster models used. The systems with dozens or hundreds of molecules and solid nanoparticles of almost real sizes (>40 units, >2 nm) or calculated with periodic boundary conditions and expanded cells give more adequate nonlocal characteristics than much smaller systems with several molecules and small clusters (<10 units, <1 nm) can give.
Dwell‐time‐dependent conditions for exponential stability and hybrid L2 × l2‐gain of linear neutral time‐delay systems with impulsive effects
Authors: Chen Jialin , Chen Wu‐Hua , Lu Xiaomei
Published: March 2021

This article considers the problems of achieving exponential stability and finite hybrid L2 × l2‐gain with respect to continuous and discrete disturbances for linear neutral time‐delay systems with impulsive effects. In the framework of descriptor system representation, a piecewise timer‐dependent Lyapunov functional is introduced to analyze the double impacts of state‐delay and impulse‐dwell‐time on stability of the underlying system. This functional depends on the state over an impulse interval and the state over a delay interval. Its construction is based on a delay‐fractioning scheme which ensures all delay subintervals contains at most one impulse instant. The relations among the augmented state variables are explored by using the impulse‐timer functions and the Newton–Leibniz formula. It is proved that the positive definiteness property of the functional at nonimpulse instants is not necessary for ensuring stability. The hybrid L2 × l2‐gain analysis is carried out by jointly using the introduced functional and a discrete‐time Lyapunov function. The obtain criteria for exponential stability and hybrid L2 × l2‐gain are expressed in terms of linear matrix inequalities. Their effectiveness is verified through two numerical examples.
Distributed adaptive cubature information filtering for bounded noise system in wireless sensor networks
Authors: Zhang Jiahao , Gao Shesheng , Xia Juan , Li Guo , Qi Xiaomin , Gao Bingbing
Published: March 2021

This article is concerned with the nonlinear state estimation for the multisenor networked system with uncertain bounded noise. Traditional distributed methods only pay attention to the information fusion of state estimations, but neglect the fusion of noise statistics. The difference of noise statistics among sensor nodes usually affects the precision of state estimation in wireless sensor networks, especially for the distributed state estimation. In this article, in order to improve the accuracy of noise statistic estimations, a distributed noise statistic estimator is derived based on covariance intersection criterion and modified Sage–Husa maximum posterior. Then, distributed adaptive cubature information filtering (DACIF) is founded based on weighted average consensus to obtain accurate state estimation. Two‐step information fusion, including the information fusion of state estimations and noise statistics, is derived to enhance the precision of state estimations. Meanwhile, a novel weighted rule is devised based on the state and measurement innovation vectors to improve the accuracy of distribution information fusion. Next, the estimation errors of DACIF are proved to be bounded in mean square. Simulations and semisimulation experiments are conducted to verify the effectiveness of the proposed algorithm.
Preclinical Assessment of Dual CYP26[A1/B1] Inhibitor, DX308, as an Improved Treatment for Keratinization Disorders
Authors: Veit J.G.S. , Poumay Y. , Mendes D. , Kreitinger J. , Walker L. , Paquet A. , Menigot C. , Zolezzi F. , Paller A.S. , Diaz P.
Published: March 2021

Background

Retinoid-based therapies are commonly used in the treatment of disorders of keratinization and other skin disorders but can result in non-specific effects and adverse reactions. Use of retinoic acid metabolism blocking agents (RAMBAs) such as DX308 may address these shortcomings.

Objectives

Characterize the therapeutic potential of recently discovered, CYP26-selective RAMBA, DX308.

Materials and Methods

Preliminary in vitro assessment of potential off-target activity, metabolic and toxicologic profiling. Studies to assess safety and efficacy of topical treatment in correcting abnormal skin morphology in rhino mice. Extensive gene expression profiling by RNA sequencing and qPCR in 3D epidermis grown with keratinocytes (KCs) from keratinization disorders and healthy controls, to investigate modulation of retinoid biopathways.

Results

In vitro, DX308 does not interact with off-target nuclear receptors or CYP450s, is not genotoxic, and is stable in skin, despite vigorous hepatic metabolism. In vivo, topical DX308 induces comedolysis and epidermal thickening without apparent adverse effects. Gene expression profiling shows potent modulation of retinoid-responsive genes by DX308 in both healthy and keratinization disorder KCs. Pathway analysis suggests DX308 may inhibit inflammatory and immune responses in KCs.

Conclusions

These preliminary studies suggest that DX308 is an efficacious topical therapeutic with a favourable metabolic and safety profiles. DX308 may present an improved therapeutic alternative for the treatment of keratinization disorders and other retinoid-responsive skin ailments.
Prevalence and changes in depressive symptoms among postgraduate students: A systematic review and meta‐analysis from 1980 to 2020
Authors: Guo Liping , Fan Huiyong , Xu Zheng , Li Jieyun , Chen Taolin , Zhang Ziyao , Yang Kehu
Published: March 2021

Education actively helps us develop our well‐being and health, but postgraduate students are at high risk of depression. The prevalence of depression symptoms varies from 6.2% to 84.7% among them, and its changes throughout the years remains unclear. The present study aimed to estimate the real prevalence of depression symptoms among postgraduate students and the changes from 1980 to 2020. Thirty‐seven primary studies with 41 independent reports were included in the meta‐analysis (none reports were in high‐quality, three were medium‐to‐high quality, 20 were low‐to‐medium quality, and 18 were low‐quality), involving 27,717 postgraduate students. The pooled prevalence of overall, mild, moderate, and severe depression symptoms was 34% (95% CI: 28–40, I2 = 98.6%), 27% (95% CI: 22–32, I2 = 85.8%), 13% (95% CI: 8–21, I2 = 97.3%), and 8% (95% CI: 6–11, I2 = 81.0%), respectively. Overall, the prevalence of depression symptoms remained relatively constant through the years following 1980 (overall: β = −0.12, 95% CI: [−0.39, 0.15], p = 0.39; mild: β = 0.24, 95% CI: [−0.02, 0.51], p = 0.07; moderate: β = −0.24, 95% CI: [−0.75, 0.26], p = 0.34; severe: β = 0.13, 95% CI: [−0.25, 0.51], p = 0.50). Doctoral students experienced more depressive symptoms than did master's students (43% vs. 27%; Q = 2.23, df = 1, p = 0.13), and studies utilising non‐random sampling methods reported a higher prevalence of mild depression and lower moderate depression symptoms than those that used random sampling (overall: 34% vs. 29%; Q = 0.45, df = 1, p = 0.50; mild: 29% vs. 21%; Q = 1.69, df = 1, p = 0.19; moderate: 16% vs. 25%; Q = 1.79, df = 1, p = 0.18; severe: 8% vs. 9%; Q = 0.13, df = 1, p = 0.72) despite these differences was not statistically significant. The prevalence of depression symptoms was moderated by the measurements and the quality of primary studies. More than one‐third of postgraduates reported depression symptoms, which indicates the susceptibility to mental health risk among postgraduates. School administrators, teachers, and students should take joint actions to prevent mental disorders of postgraduates from increasing in severity.
The Functional Chameleon of Materials Chemistry—Combining Carbon Structures into All‐Carbon Hybrid Nanomaterials with Intrinsic Porosity to Overcome the “Functionality‐Conductivity‐Dilemma” in Electrochemical Energy Storage and Electrocatalysis
Authors: Ilic Ivan K. , Oschatz Martin
Published: March 2021

Nanoporous carbon materials can cover a remarkably wide range of physicochemical properties. They are widely applied in electrochemical energy storage and electrocatalysis. As a matter of fact, all these applications combine a chemical process at the electrode–electrolyte interface with the transport (and possibly the transfer) of electrons. This leads to multiple requirements which can hardly be fulfilled by one and the same material. This “functionality‐conductivity‐dilemma” can be minimized when multiple carbon‐based compounds are combined into porous all‐carbon hybrid nanomaterials. This article is giving a broad and general perspective on this approach from the viewpoint of materials chemists. The problem and existing solutions are first summarized. This is followed by an overview of the most important design principles for such porous materials, a chapter discussing recent examples from different fields where the formation of comparable structures has already been successfully applied, and an outlook over the future development of this field that is foreseen.
Progress in p‐type Tunnel Oxide‐Passivated Contact Solar Cells with Screen‐Printed Contacts
Authors: Mack Sebastian , Herrmann David , Lenes Martijn , Renes Marten , Wolf Andreas
Published: March 2021

Herein, an update on the work on high‐efficiency p‐type solar cells with p‐type‐passivating rear contacts formed by low‐pressure chemical vapor deposition and screen‐printed contacts is given. It is shown that thin polysilicon layers enable a high level of surface passivation but do show increased contact resistivity and especially contact recombination. Commercially available pastes and dependence of contact resistivity and contact recombination on polylayer thickness and firing set temperature are investigated. For 240 nm‐thick poly‐Si layers, the values down to 4 mΩ cm2 and 60 fA cm−2 are observed. For the presented process sequence, improved hydrogenation as one possibility to increase the passivation quality of the passivating contact structure is identified. Implementing all findings into a final solar cell, a maximum total area conversion efficiency of 21.2% is reported.
Beyond the First Quadrant: Origin of the High Frequency Intensity‐Modulated Photocurrent/Photovoltage Spectroscopy Response of Perovskite Solar Cells
Authors: Pockett Adam , Spence Michael , Thomas Suzanne K. , Raptis Dimitrios , Watson Trystan , Carnie Matthew J.
Published: March 2021

The complete interpretation of small perturbation frequency‐domain measurements on perovskite solar cells has proven to be challenging. This is particularly true in the case of intensity‐modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS) measurements in which the high frequency response is obscured by instrument limitations. Herein, a new experimental methodology capable of accurately resolving the high frequency response—often observable in the second and third quadrants of the complex plane—of a range of perovskite devices is demonstrated. By combining single‐frequency IMPS/IMVS measurements, it is able to construct the time dependence of the IMPS/IMVS response of these devices during their initial response to illumination. This reveals significant negative photocurrent/photovoltage signals at high frequency while devices reach steady state, which is in keeping with observations made from comparable time‐domain transient measurements. These techniques allow the underlying interfacial recombination and ion migration processes to be assessed, which are not always evident using steady‐state measurements. The ability to study and mitigate these processes is vital in optimizing the real‐world operation of devices.
An Analysis of the Systemic Structure of the U.S. Constitution Providing New Insight into the Fragmentation and Conflict Facing U.S. Society and Providing Guidance Towards More Effective Governance
Authors: Wallis Steven E.
Published: March 2021

To a great extent, the effectiveness of a government may be traced to its constituting documents which serve as a guide or map for how it is supposed to function. From a systems perspective, we may expect a more systemic Constitution to inform the operation of a government that is more systemic and so more effective. This paper uses Integrative Propositional Analysis (IPA) to conduct a preliminary evaluation of the systemic structure of the US Constitution. The analysis finds that the US Constitution has a vanishingly low level of structure. This previously unrecognized lack of structure provides a new explanation for why the nation is increasingly misgoverned (and/or more difficult to govern) and why divisions are deepening between partisan groups, leading to argument and conflict. A path forward is suggested to develop a more systemic Constitution and more effective governance; one supporting a more just, prosperous, and sustainable society.
Causes of Corner Cracks in Hypoperitectic Microalloyed Steel Billets
Authors: Xing Lidong , Zhang Zefeng , Bao Yanping , Chen Botao , Zheng Fanzheng , Wang Min
Published: March 2021

Due to the development of continuous casting technology, the incidence of cracks in the continuous casting process has been significantly reduced. However, a few small cracks still appear during the continuous casting of special steel. For instance, cracks often appear at the corner of the billet during the production of hypoperitectic microalloyed steel. Most research on the causes of corner cracks in hypoperitectic microalloyed steel has focused on investigating the hot ductility of steel and not considered the shrinkage characteristics during solidification. Herein, the hot ductility behavior show that cracks are not related to the hot brittleness of steel. The effects of alloy composition on the phase evolution and shrinkage of steel during solidification are focused. Uneven solidification leads to excessive shrinkage of the corners in the billet, and an air gap is generated between the billet and the mold. The return of temperature in the corner of the billet results in the coarseness of the corner grain. Abnormal solidification also results in the severe deformation of the billet, leading to severe wear with the mold, causing Cu to infiltrate into the billet, and further increasing the crack sensitivity of the steel.
The Potential of the Internal Friction Technique to Evaluate the Role of Vacancies and Dislocations in the Hydrogen Embrittlement of Steels
Authors: Vandewalle Liese , Konstantinović Milan J. , Depover Tom , Verbeken Kim
Published: March 2021

Hydrogen embrittlement of steels is known to have considerable impact in many engineering sectors. To be able to mitigate the hydrogen embrittlement problem, a profound comprehension of the interaction of hydrogen with the steel microstructure is required. Especially the interaction of hydrogen with dislocations and vacancies is very relevant as these defects are known to play an important role in hydrogen embrittlement. At present, thermal desorption spectroscopy is mostly used to study hydrogen–defect interactions. However, information obtained solely by this technique is insufficient to obtain a full understanding of the interaction of hydrogen with these defects in the steel microstructure. Herein, the use of internal friction, as a complementary technique to thermal desorption spectroscopy, to reveal the interaction of hydrogen with dislocations and vacancies, is reviewed based on the present understanding in the literature. Furthermore, the opportunities to use internal friction to characterize the interaction between hydrogen and these defects and to give more insight into the hydrogen embrittlement mechanism are discussed. It is demonstrated that internal friction has not yet been used to its full potential for this purpose, although it entails the opportunity to develop fundamental insights into the hydrogen embrittlement phenomenon.
Laboratory Study on the Sintering Behavior of Zircon‐Based Ladle Filler Sands
Authors: Deng Zhiyin , Yang Boran , Zhu Miaoyong
Published: March 2021

To understand the sintering behavior of zircon‐based filler sands, laboratory experiments are conducted, and the effect of steel grades containing different contents of Mn and Al is studied. The results show that zircon filler sands have a sufficient sintering performance without the influence of steel. The reaction between the mullite grains and the decomposed zircon grains results in the formation of a liquid phase, making the sand grains bond. Liquid steel (even liquid pure iron) evidently impacts the sintering of zircon filler sands. Similar to chromite filler sands, the effect of Mn in liquid steel on the sintering of zircon filler sands is also remarkable, whereas the effect of Al (up to 250 ppm) is not so profound due to the existence of the mullite grains. In most cases of conventional Al‐killed steel grades (Al ≤ 300 ppm), zircon‐based filler sands show a sufficient sintering effect, whereas they are not suitable for high‐Mn and high‐Al steel grades due to the serious sintering result.
A New Conversion Method to Evaluate the Hazard Potential of Collaborative Robots in Free Collisions
Authors: Herbster Sebastian , Behrens Roland , Elkmann Norbert
Published: March 2021

With the increasing importance of collaborative robots in industrial manufacturing, their economic efficiency is becoming more and more important. Today, one approach to prevent collaborative robots from injuring humans is to assure that the robot cannot exceed biomechanical limits in the event of an accidental collision or clamping. The ability of the robot to avoid collision forces beyond the limits must be validated with a biofidelic measurement device that mimics the biomechanical behavior of the human. For reliable use, the measurement devices must be attached to a rigid frame. Consequently, the test setup is solely able to simulate the contact dynamics and biomechanical consequences of a clamping contact in which the human body part cannot move. Free collisions that allow the human to move freely reduce the collision forces, but can only be evaluated with such a measurement device. This technical limitation leads to slower robots and thus a loss of productivity. The study presents a method that increases the efficiency of safe collaborative robots by adding a new validation procedure. The presented method incorporates a model-based conversion of measurements that enables safety experts to validate robots in free collisions. Data from experimental tests with a collaborative robot and a biofidelic measurement device show a good fit of the model-based prediction and thus confirm our approach. This new approach has great potential to increase the productivity of collaborative robots, since our method will allow them to move at faster but still safe speeds.
Islands in linear dilaton black holes
Authors: Karananas Georgios K. , Kehagias Alex , Taskas John
Published: March 2021

Abstract

We derive a novel four-dimensional black hole with planar horizon that asymptotes to the linear dilaton background. The usual growth of its entanglement entropy before Page’s time is established. After that, emergent islands modify to a large extent the entropy, which becomes finite and is saturated by its Bekenstein-Hawking value in accordance with the finiteness of the von Neumann entropy of eternal black holes. We demonstrate that viewed from the string frame, our solution is the two-dimensional Witten black hole with two additional free bosons. We generalize our findings by considering a general class of linear dilaton black hole solutions at a generic point along theσ-model renormalization group (RG) equations. For those, we observe that the entanglement entropy is “running” i.e. it is changing along the RG flow with respect to the two-dimensional worldsheet length scale. At any fixed moment before Page’s time the aforementioned entropy increases towards the infrared (IR) domain, whereas the presence of islands leads the running entropy to decrease towards the IR at later times. Finally, we present a four-dimensional charged black hole that asymptotes to the linear dilaton background as well. We compute the associated entanglement entropy for the extremal case and we find that an island is needed in order for it to follow the Page curve.
Effect of Periodic Arrays of Defects on Lattice Energy Minimizers
Authors: Bétermin Laurent
Published: March 2021

We consider interaction energies $$E_f[L]$$

E
f

[
L
]

between a point $$O\in {\mathbb {R}}^d$$

O
∈

R

d

, $$d\ge 2$$

d
≥
2

, and a lattice L containing O, where the interaction potential f is assumed to be radially symmetric and decaying sufficiently fast at infinity. We investigate the conservation of optimality results for $$E_f$$

E
f

when integer sublattices kL are removed (periodic arrays of vacancies) or substituted (periodic arrays of substitutional defects). We consider separately the non-shifted ($$O\in k L$$

O
∈
k
L

) and shifted ($$O\not \in k L$$

O
∉
k
L

) cases and we derive several general conditions ensuring the (non-)optimality of a universal optimizer among lattices for the new energy including defects. Furthermore, in the case of inverse power laws and Lennard-Jones-type potentials, we give necessary and sufficient conditions on non-shifted periodic vacancies or substitutional defects for the conservation of minimality results at fixed density. Different examples of applications are presented, including optimality results for the Kagome lattice and energy comparisons of certain ionic-like structures.
Gender differences in wage expectations: the role of biased beliefs
Authors: Briel Stephanie , Osikominu Aderonke , Pfeifer Gregor , Reutter Mirjam , Satlukal Sascha
Published: March 2021

We analyze gender differences in expected starting salaries along the wage expectations distribution of prospective university students in Germany, using elicited beliefs about both own salaries and salaries for average other students in the same field. Unconditional and conditional quantile regressions show 5–15% lower wage expectations for females. At all percentiles considered, the gender gap is more pronounced in the distribution of expected own salary than in the distribution of wages expected for average other students. Decomposition results show that biased beliefs about the own earnings potential relative to others and about average salaries play a major role in explaining the gender gap in wage expectations for oneself.
A new perspective on calmodulin-regulated calcium and ROS homeostasis upon carbon black nanoparticle exposure
Authors: Verma Nisha , Pink Mario , Schmitz-Spanke Simone
Published: March 2021

Toxicological studies propose that exposure to carbon black nanoparticles induces organ injuries and inflammatory responses. Besides, current understanding of the molecular mechanisms implies that carbon black nanoparticles (CBNP) exposure induces the production of reactive oxygen species (ROS) causing inflammation, mitochondrial dysfunction or disturbance in calcium homeostasis. However, the precise mechanisms whereby CBNP exert these effects in the lung are still not fully understood. To gain insight into the possible mechanism of CBNP exerted toxicity, human alveolar epithelial cells (A549) were exposed to different concentrations of CBNP and for different timepoints. The reaction of the cells was monitored by the systematic use of cell-based measurements of calcium and ROS, in the presence and absence of calcium (Ca2+) pump inhibitors/chelators and antioxidants. Followed by an in-depth PCR analysis of 84 oxidative stress-related genes. The measurements revealed, as compared to the control, that exposure to CBNP nanoparticles leads to the generation of high ROS levels, as well as a disturbance in calcium homeostasis, which remained primarily unchanged even after 24 h of exposure. Nevertheless, in presence of antioxidants N-acetylcysteine (NAC) and Trolox, ROS formation was considerably reduced without affecting the intracellular calcium concentration. On the other hand, Ca2+ pump inhibitors/chelators, BAPTA (1,2-bis(o-amino phenoxy)ethane-N, N, N′, N′-tetraacetic acid) and verapamil not only decreased the Ca2+ overload, but also further decreased the ROS formation, indicating its role in CBNP-induced oxidative stress. Further, a PCR array analysis of A549 cells in presence and absence of the calmodulin (CaM) antagonist W7, indicated toward nine altered oxidative stress-related genes which further confirmed our cytotoxicity results. Obtained data suggested that CBNP exposure elevates calcium ion concentration, which further contributes to oxidative stress, via the calcium-binding protein CaM. Its inhibition with W7 leads to downregulation in gene expression of nine oxidative stress-related genes, which otherwise, as compared to control, show increased gene expression. The results of the study thus confirm that exposure of lung epithelial cells to CBNP leads to oxidative stress; however, the oxidative stress itself is a result of a disturbance in both calcium and ROS homeostasis, and should be considered while searching for a new strategy for prevention of CBNP-induced lung toxicity.
Essentials in saline pharmacology for nasal or respiratory hygiene in times of COVID-19
Authors: Huijghebaert Suzy , Hoste Levi , Vanham Guido
Published: March 2021

Purpose

Nasal irrigation or nebulizing aerosol of isotonic or hypertonic saline is a traditional method for respiratory or nasal care. A recent small study in outpatients with COVID-19 without acute respiratory distress syndrome suggests substantial symptom resolution. We therefore analyzed pharmacological/pharmacodynamic effects of isotonic or hypertonic saline, relevant to SARS-CoV-2 infection and respiratory care.

Methods

Mixed search method.

Results

Due to its wetting properties, saline achieves an improved spreading of alveolar lining fluid and has been shown to reduce bio-aerosols and viral load. Saline provides moisture to respiratory epithelia and gels mucus, promotes ciliary beating, and improves mucociliary clearance. Coronaviruses and SARS-CoV-2 damage ciliated epithelium in the nose and airways. Saline inhibits SARS-CoV-2 replication in Vero cells; possible interactions involve the viral ACE2-entry mechanism (chloride-dependent ACE2 configuration), furin and 3CLpro (inhibition by NaCl), and the sodium channel ENaC. Saline shifts myeloperoxidase activity in epithelial or phagocytic cells to produce hypochlorous acid. Clinically, nasal or respiratory airway care with saline reduces symptoms of seasonal coronaviruses and other common cold viruses. Its use as aerosol reduces hospitalization rates for bronchiolitis in children. Preliminary data suggest symptom reduction in symptomatic COVID-19 patients if saline is initiated within 48 h of symptom onset.

Conclusions

Saline interacts at various levels relevant to nasal or respiratory hygiene (nasal irrigation, gargling or aerosol). If used from the onset of common cold symptoms, it may represent a useful add-on to first-line interventions for COVID-19. Formal evaluation in mild COVID-19 is desirable as to establish efficacy and optimal treatment regimens.
Convolutional neural networks for PET functional volume fully automatic segmentation: development and validation in a multi-center setting
Authors: Iantsen Andrei , Ferreira Marta , Lucia Francois , Jaouen Vincent , Reinhold Caroline , Bonaffini Pietro , Alfieri Joanne , Rovira Ramon , Masson Ingrid , Robin Philippe , Mervoyer Augustin , Rousseau Caroline , Kridelka Frédéric , Decuypere Marjolein , Lovinfosse Pierre , Pradier Olivier , Hustinx Roland , Schick Ulrike , Visvikis Dimitris , Hatt Mathieu
Published: March 2021

Purpose

In this work, we addressed fully automatic determination of tumor functional uptake from positron emission tomography (PET) images without relying on other image modalities or additional prior constraints, in the context of multicenter images with heterogeneous characteristics.

Methods

In cervical cancer, an additional challenge is the location of the tumor uptake near or even stuck to the bladder. PET datasets of 232 patients from five institutions were exploited. To avoid unreliable manual delineations, the ground truth was generated with a semi-automated approach: a volume containing the tumor and excluding the bladder was first manually determined, then a well-validated, semi-automated approach relying on the Fuzzy locally Adaptive Bayesian (FLAB) algorithm was applied to generate the ground truth. Our model built on the U-Net architecture incorporates residual blocks with concurrent spatial squeeze and excitation modules, as well as learnable non-linear downsampling and upsampling blocks. Experiments relied on cross-validation (four institutions for training and validation, and the fifth for testing).

Results

The model achieved good Dice similarity coefficient (DSC) with little variability across institutions (0.80 ± 0.03), with higher recall (0.90 ± 0.05) than precision (0.75 ± 0.05) and improved results over the standard U-Net (DSC 0.77 ± 0.05, recall 0.87 ± 0.02, precision 0.74 ± 0.08). Both vastly outperformed a fixed threshold at 40% of SUVmax (DSC 0.33 ± 0.15, recall 0.52 ± 0.17, precision 0.30 ± 0.16). In all cases, the model could determine the tumor uptake without including the bladder. Neither shape priors nor anatomical information was required to achieve efficient training.

Conclusion

The proposed method could facilitate the deployment of a fully automated radiomics pipeline in such a challenging multicenter context.
Hypermetabolic lymphadenopathy following administration of BNT162b2 mRNA Covid-19 vaccine: incidence assessed by [18F]FDG PET-CT and relevance to study interpretation
Authors: Cohen Dan , Krauthammer Shir Hazut , Wolf Ido , Even-Sapir Einat
Published: March 2021

Purpose

Nationwide mass vaccination against Covid-19 started in Israel in late 2020. Soon we identified on [18F]FDG PET-CT studies vaccine-associated hypermetabolic lymphadenopathy (VAHL) in axillary or supraclavicular lymph nodes (ASLN) ipsilateral to the vaccination site. Sometimes, differentiation between the malignant and benign nature of the hypermetabolic lymphadenopathy (HLN) could not be made, and equivocal HLN (EqHL) was reported. The purpose of the study was to determine the overall incidence of VAHL after BNT162b2 vaccination and also its relevance to PET-CT interpretation in oncologic patients.

Methods

A total of 951 consecutive patients that underwent [18F]FDG PET-CT studies in our department were interviewed regarding the sites and dates of the vaccine doses. A total of 728 vaccinated patients (All-Vac group) were included: 346 received the first dose only (Vac-1 group) and 382 received the booster dose as well (Vac-2 group). Studies were categorized as no HLN, malignant-HLN (MHL), VAHL, or EqHL. In studies with VAHL, location, [18F]FDG-intensity uptake and nodes size were recorded.

Results

The incidences of HLN were 45.6%, 36.4%, and 53.9% in All-Vac, Vac-1, and Vac-2 groups, respectively. VAHL was reported in 80.1% of vaccinated patients with HLN. Lower incidences of VAHL were found during the first 5 days or in the third week after the first vaccine and beyond 20 days after the booster dose. In 49 of 332 (14.8%) vaccinated patients, we could not determine whether HLN was MHL or VAHL. Breast cancer and lymphoma were the leading diseases with EqHL.

Conclusion

VAHL is frequently observed after BNT162b2 administration, more commonly and with higher intensity following the booster dose. To minimize false and equivocal reports in oncological patients, timing of [18F]FDG PET-CT should be based on the time intervals found to have a lower incidence of VAHL, and choice of vaccine injection site should be advised, mainly in patients where ASLN are a relevant site of tumor involvement.
The Relationship Between Co‐morbidity, Screen‐Detection and Outcome in Patients Undergoing Resection for Colorectal Cancer
Authors: Johnstone Mark S. , McMillan Donald C. , Horgan Paul G. , Mansouri David
Published: March 2021

Background

Bowel cancer screening increases early stage disease detection and reduces cancer‐specific mortality. We assessed the relationship between co‐morbidity, screen‐detection and survival in colorectal cancer.

Methods

A retrospective, observational cohort study compared screen‐detected (SD) and non‐screen‐detected (NSD) patients undergoing potentially curative resection (April 2009–March 2011). Co‐morbidity was quantified using ASA, Lee and Charlson Indices. Systemic inflammatory response was measured using the neutrophil lymphocyte ratio (NLR). Covariables were compared using crosstabulation and the χ2 test for linear trend. Survival was analysed using Cox Regression.

Results

Of 770 patients, 331 had SD‐ and 439 NSD‐disease. A lower proportion of SD patients had a high ASA (≥3) compared to NSD (27.2% vs 37.3%; p = 0.007). There was no significant difference in the proportion of patients with a high (≥2) Lee Index (16.3% SD vs 21.9% NSD; p = 0.054) or high (≥3) Charlson Index (22.7% SD vs 26.9% NSD; p = 0.181). On univariate analysis, NSD (HR 2.182 (1.594–2.989;p < 0.001)), emergency presentation (HR 3.390 (2.401–4.788; p < 0.001)), advanced UICC‐TNM (III or IV) (p < 0.001), high ASA (≥3) (HR 1.857 (1.362–2.532; p < 0.001)), high Charlson Index (≥3) (HR 1.800 (1.333–2.432; p < 0.001)) and high (≥3) NLR (HR 1.825 (1.363–2.442; p < 0.001)) were associated with poorer overall survival (OS). NSD predicted poorer cancer‐specific survival (CSS) (HR 2.763 (1.776–4.298; p < 0.001)). On multivariate analysis, NSD retained significance as an independent predictor of poorer OS (HR 1.796 (1.224–2.635; p = 0.003)) and CSS (HR 1.924 (1.193–3.102; p = 0.007)).

Conclusions

Patients with SD cancers have significantly lower ASA scores. After adjusting for ASA, co‐morbidity and a broad range of covariables, SD patients retain significantly better OS and CSS.