bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiomic Analysis of Native T1 Mapping Images Discriminates Between MYH7 and MYBPC3‐Related Hypertrophic Cardiomyopathy
Authors: Wang Jie , Yang Fuyao , Liu Wentao , Sun Jiayu , Han Yuchi , Li Dong , Gkoutos Georgios V. , Zhu Yanjie , Chen Yucheng
Published: June 2020

Background

The phenotype via conventional cardiac MRI analysis of MYH7 (β‐myosin heavy chain)‐ and MYBPC3 (β‐myosin‐binding protein C)‐associated hypertrophic cardiomyopathy (HCM) groups is similar. Few studies exist on the genotypic–phenotypic association as assessed by machine learning in HCM patients.

Purpose

To explore the phenotypic differences based on radiomics analysis of T1 mapping images between MYH7 and MYBPC3‐associated HCM subgroups.

Study Type

Prospective observational study.

Subjects

In all, 102 HCM patients with pathogenic, or likely pathogenic mutation, in MYH7 (n = 68) or MYBPC3 (n = 34) genes.

Field Strength/Sequence

Cardiac MRI was performed at 3.0T with balanced steady‐state free precession (bSSFP), phase‐sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE), and modified Look–Locker inversion recovery (MOLLI) T1 mapping sequences.

Assessment

All patients underwent next‐generation sequencing and Sanger genetic sequencing. Left ventricular native T1 and LGE were analyzed. One hundred and fifty‐seven radiomic features were extracted and modeled using a support vector machine (SVM) combined with principal component analysis (PCA). Each subgroup was randomly split 4:1 (feature selection / test validation).

Statistical Tests

Mann–Whitney U‐tests and Student's t‐tests were performed to assess differences between subgroups. A receiver operating characteristic (ROC) curve was used to assess the model's ability to stratify patients based on radiomic features.

Results

There were no significant differences between MYH7‐ and MYBPC3‐associated HCM subgroups based on traditional native T1 values (global, basal, and middle short‐axis slice native T1; P = 0.760, 0.914, and 0.178, respectively). However, the SVM model combined with PCA achieved an accuracy and area under the curve (AUC) of 92.0% and 0.968 (95% confidence interval [CI]: 0.968–0.971), respectively. For the test validation dataset, the accuracy and AUC were 85.5% and 0.886 (95% CI: 0.881–0.901), respectively.

Data Conclusion

Radiomic analysis of native T1 mapping images may be able to discriminate between MYH7‐ and MYBPC3‐associated HCM patients, exceeding the performance of conventional native T1 values.

Level of Evidence

3

Technical Efficacy Stage

2 J. MAGN. RESON. IMAGING 2020;52:1714–1721.
Evaluating the Relationship Between Dynamic Contrast‐Enhanced MRI (DCE‐MRI) Parameters and Pathological Characteristics in Breast Cancer
Authors: Kang Se Ri , Kim Hye Won , Kim Hun Soo
Published: June 2020

Background

Dynamic contrast‐enhanced MRI (DCE‐MRI) is used to evaluate tumor microvasculature. However, studies demonstrating an association between perfusion parameters derived from DCE‐MRI and histopathologic characteristics are limited to a small set of histopathologic factors, and the results are inconsistent.

Purpose

To evaluate the relationship between DCE‐MRI perfusion parameters and common histopathologic tumor characteristics used to predict angiogenesis and determine prognosis in breast cancer.

Study Type

Retrospective.

Population

In all, 105 breast cancer patients with invasive ductal carcinoma (122 lesions).

Field Strength/Sequence

3.0T, turbo spin‐echo (TSE) T1‐weighted, fat‐suppressed T2‐weighted, TSE T2‐weighted, and dynamic unenhanced and contrast‐enhanced 3D T1 high‐resolution isotropic volume examination.

Assessment

One reviewer obtained perfusion parameters (Ktrans, kep, ve, and vp) of each breast cancer from DCE MRI using the extended Tofts model with a fixed baseline T1 value and a population‐based arterial input function. The relationship between DCE‐MRI perfusion parameters and histopathologic tumor characteristics used to predict angiogenesis and determine prognosis was evaluated.

Statistical Tests

Student's t‐test, Mann–Whitney U‐test, analysis of variance (ANOVA), and Kruskal–Wallis test were used.

Results

Triple‐negative breast cancers exhibited higher Ktrans and kep than luminal cancers (P < 0.05). Estrogen receptor (ER)‐negative tumors showed higher Ktrans than ER‐positive tumors (P < 0.05). Progesterone receptor (PR)‐negative tumors presented higher ve than PR‐positive tumors (P < 0.05). Tumors with higher Ki‐67 showed higher kep than tumors with lower Ki‐67 (P < 0.05). P53‐positive tumors exhibited higher Ktrans and kep than p53‐negative tumors (P < 0.05). Higher histologic grade tumors (grade II/III) presented higher Ktrans, kep, vp (P < 0.05) than grade I tumors. Tumors with LVSI presented higher Ktrans and kep than tumors without LVSI (P < 0.05).

Data Conclusion

Breast cancer presenting higher Ktrans and kep on DCE‐MRI was associated with poor prognostic histopathologic factors. Therefore, pretreatment DCE‐MRI perfusion parameters may be useful imaging biomarkers for the evaluation of tumor prognosis and angiogenesis.

Level of Evidence

3

Technical Efficacy Stage

2
Conscientiousness in Teams Completing Creative Tasks: Does it Predict?
Authors: Taggar Simon
Published: June 2020

The relationship between conscientiousness and creativity remains equivocal. This is surprising because conscientiousness is a good predictor of job performance across most criteria and occupations. In this longitudinal study, I found support for the achievement striving and the dependability aspects of conscientiousness affecting team member creativity in different ways. Specifically, the achievement striving aspect of conscientiousness positively predicts creative self‐efficacy, but the dependability aspect negatively predicts creative self‐efficacy. Conversely, dependability positively predicts teamwork self‐efficacy, while achievement striving is unrelated to teamwork self‐efficacy. Creative self‐efficacy partially mediates between achievement striving and team member creativity. Both creative self‐efficacy and teamwork self‐efficacy mediate between dependability and team member creativity.
The Kilim plot: A tool for visualizing network meta‐analysis results for multiple outcomes
Authors: Seo Michael , Furukawa Toshi A. , Veroniki Areti Angeliki , Pillinger Toby , Tomlinson Anneka , Salanti Georgia , Cipriani Andrea , Efthimiou Orestis
Published: June 2020

Network meta‐analysis (NMA) can be used to compare multiple competing treatments for the same disease. In practice, usually a range of outcomes is of interest. As the number of outcomes increases, summarizing results from multiple NMAs becomes a nontrivial task, especially for larger networks. Moreover, NMAs provide results in terms of relative effect measures that can be difficult to interpret and apply in every‐day clinical practice, such as the odds ratios. In this article, we aim to facilitate the clinical decision‐making process by proposing a new graphical tool, the Kilim plot, for presenting results from NMA on multiple outcomes. Our plot compactly summarizes results on all treatments and all outcomes; it provides information regarding the strength of the statistical evidence of treatment effects, while it illustrates absolute, rather than relative, effects of interventions. Moreover, it can be easily modified to include considerations regarding clinically important effects. To showcase our method, we use data from a network of studies in antidepressants. All analyses are performed in R and we provide the source code needed to produce the Kilim plot, as well as an interactive web application.
Novel Method for Ultrasound‐Derived Fat Fraction Using an Integrated Phantom
Authors: Labyed Yassin , Milkowski Andy
Published: June 2020

Objectives

The purpose of this study was to demonstrate the clinical feasibility of an integrated reference phantom method for quantitative ultrasound by creating an ultrasound‐derived fat fraction (UDFF) tool. This tool was evaluated with respect to its diagnostic performance as a biomarker for assessing histologic hepatic steatosis and its agreement with the magnetic resonance imaging (MRI) proton density fat fraction (PDFF).

Methods

Adults (n = 101) with known or suspected nonalcoholic fatty liver disease consented to participate in this prospective cross‐sectional study. All patients underwent MRI‐PDFF and ultrasound scans, whereas 90 underwent liver biopsy. A linear least‐squares analysis used the attenuation coefficient and backscatter coefficient to create the UDFF model for predicting MRI‐PDFF.

Results

The area under the receiver operating characteristic curve values were 0.94 (95% confidence interval [CI], 0.85–0.98) for histologic steatosis grade 0 (n = 6) versus 1 or higher (n = 84), 0.88 (95% CI, 0.8–0.94) for grade 1 or lower (n = 45) versus 2 or higher (n = 45), and 0.83 (95% CI, 0.73–0.9) for grade 2 or lower (n = 78) versus 3 (n = 12). The Pearson correlation coefficient between UDFF and PDFF was ρ = 0.87 with 95% limits of agreement of ±8.5%. Additionally, the diagnosis of steatosis, defined as MRI‐PDFF higher than 5% and 10%, had area under the receiver operating characteristic curve values of 0.97 (95% CI, 0.93–0.99) and 0.95 (95% CI, 0.9–0.98), respectively. The body mass index was not correlated with either UDFF or PDFF.

Conclusions

An on‐system, integrated UDFF tool provides a simple, noninvasive, accessible, low‐cost, and commercially viable clinical tool for quantifying the hepatic fat fraction with a high degree of agreement with histologic biopsy or the MRI‐PDFF biomarker.
A detailed chemical kinetic model for the supercritical water oxidation of methylamine: The importance of imine formation
Authors: Ashraful A. M. , da Silva Gabriel
Published: June 2020

A detailed chemical kinetic model has been developed for supercritical water oxidation (SCWO) of methylamine, CH3NH2, providing insight into the intermediates and final products formed in this process as well as the dominant reaction pathways. The model was adapted from previous mechanisms, with a revision of the peroxyl radical chemistry to include imine formation, which has recently been identified as the dominant gas‐phase pathway in amine oxidation. The developed model can reproduce previous experimental data on methylamine consumption and major product formation to reasonable accuracy, although with deficiencies in describing the induction time. Our simulations indicate that oxidation of the •CH2NH2 radical to methanimine, CH2NH, is the major channel in methylamine SCWO, with subsequent hydrolysis of CH2NH providing the experimentally observed reaction products ammonia and formaldehyde. Integral‐averaged reaction rates were used to identify major reaction pathways, and a first‐order sensitivity analysis indicated that the concentration of CH3NH2 is most sensitive to OH radical kinetics. Overall, this work clarifies the importance of imine chemistry in the oxidation of nitrogen‐containing compounds and indicates that they are necessary to model these compounds in SCWO processes.
Chalcone hybrids as potential anticancer agents: Current development, mechanism of action, and structure‐activity relationship
Authors: Gao Feng , Huang Gang , Xiao Jiaqi
Published: June 2020

The continuous emergency of drug‐resistant cancers and the low specificity of anticancer agents have been the major challenges in the control and treatment of cancer, making an urgent need to develop novel anticancer agents with high efficacy. Chalcones, precursors of flavonoids and isoflavonoids, exhibit structural heterogeneity and can act on various drug targets. Chalcones which demonstrated potential in vitro and in vivo activity against both drug‐susceptible and drug‐resistant cancers, are useful templates for the development of novel anticancer agents. Hybridization of chalcone moiety with other anticancer pharmacophores could provide the hybrids which have the potential to overcome drug resistance and improve the specificity, so it represents a promising strategy to develop novel anticancer agents. This review emphasizes the development, the mechanisms of action as well as structure‐activity relationships of chalcone hybrids with potential therapeutic application for many cancers in recent 10 years.
Double nerve transfer for restoring external rotation of the glenohumeral joint after neonatal brachial plexus injury
Authors: Soldado Francisco
Published: June 2020

Introduction

The probability of spontaneous recovery of shoulder external rotation in neonatal brachial plexus injury (NBPI) is very low after the age of 18 months. We report the outcomes of double nerve transfers to restore active external rotation of the glenohumeral joint in children with NBPI after this age.

Patients and methods

Retrospective analysis of 20 children of mean age of 23.8 months with a mean follow‐up of 14.8 months. Inclusion criteria were: age > 18 months, full passive glenohumeral external rotation in abduction, and absence of severe joint deformity on MRI. The spinal accessory nerve was transferred to the infraspinatus motor branch and the long head of the triceps motor branch to the teres minor motor branch. Anterior shoulder release was associated when passive shoulder external rotation in adduction (pERADD) was <30° (n = 13, Group R vs. Group N‐no release n = 7). Active shoulder elevation and external rotation in abduction (aERABD) of the glenohumeral joint were evaluated pre‐ and postoperatively.

Results

All children except two in Group R, recovered aERABD 4–6 months after surgery. Mean postoperative aERABD was 70 ± 32.4 and 82.9 ± 11.1° and shoulder elevation gain was 24.6 ± 22.2 and 27.1 ± 29.2° for Group R and N, respectively, without statistically significant differences.

Conclusions

Late nerve transfers to external rotator muscles are effective in children with NBPI. This might be explained not only by muscle reinnervation, but also by the interruption of a previous co‐contraction or developmental apraxia.

Level of evidence

Therapeutic IV.
Detection of acidic paper recovery after alkaline nanoparticle treatment by 2D NMR relaxometry
Authors: Poggi G. , Parmentier A. , Nourinaeini S. , De Luca F.
Published: June 2020

Cellulose‐based artefacts are highly prone to degradation, especially in the presence of acidic compounds, which trigger the depolymerization of cellulose chains and lead to a loss in the original mechanical resistance of the material. Calcium hydroxide nanoparticles dispersed in organic solvent have been recently proposed for the deacidification of cellulose‐based artworks. In this work, changes induced on paper by a deacidification treatment, following an acidification bath, were studied by nuclear magnetic resonance (NMR) relaxometry and by the so‐called NMR diffraction of water trapped in the cellulose network. The deacidification treatment modifies intrachain and interchain bonds in hydrolyzed and degraded cellulose, leading to a buffered cellulose network configuration, which is similar to that characterizing the untreated reference sample in terms of relaxation parameters. Overall, calcium hydroxide nanoparticles are demonstrated effective in hindering the degradation of cellulose induced by acids and ageing in strong environmental conditions, even from the standpoint of cellulose network arrangement. It is worth noting, too, that the unilateral NMR device used for the relaxation measurements may represent a powerful tool for the preservation of cellulose‐based artworks because it allows for the monitoring of the conservation status of cellulose in a completely non‐invasive manner.
An efficient and unconditionally stable numerical algorithm for nonlinear structural dynamics
Authors: Xu Junjie , Huang Yuli , Qu Zhe
Published: June 2020

This article proposes an algorithm for express solutions in nonlinear structural dynamics. Our strategy is to adopt a typical time integrator and accept the solution after a constant number of iterations using a constant Jacobian matrix. Its success may not be initially obvious, but we demonstrate that the proposed algorithm not only is fully operational but also inherits the advantages of the host time integrators such as the unconditional stability, the order of accuracy, and the numerical dissipation that helps suppress the spurious higher mode oscillation. The use of a constant Jacobian matrix plays the key role in minimizing the computational expense associated with matrix operations. We first study the optimization of the number of iterations, then present the consistency and stability analysis followed by some examples verifying these features, and conclude by showing the exponential efficiency improvement in a response history analysis of a high‐rise building fully equipped with nonlinearities.
Quantifying seasonal 3D effects for a permanent electrical resistivity tomography monitoring system along the embankment of an irrigation canal
Authors: Hojat Azadeh , Arosio Diego , Ivanov Vladislav Ivov , Loke Meng Heng , Longoni Laura , Papini Monica , Tresoldi Greta , Zanzi Luigi
Published: June 2020

In this paper, we discuss the necessity of quantifying and correcting seasonal 3D effects on 2D electrical resistivity tomography (ERT) data measured along the embankments of rivers or artificial canals. A permanent ERT monitoring system has been continuously operating along the levee of an irrigation canal in Mantua province, Italy, since September 2015. To evaluate the importance of 3D effects and their dependence on seasonal variations, we first performed numerical simulations and also laboratory tests on downscaled levees of the study site. The results showed that 2D apparent resistivity pseudosections measured along the levee are significantly affected by 3D effects of the embankment geometry. Moreover, it was observed that 3D effects not only depend on the levee geometry, but they are also affected by seasonal fluctuations in the water level in the canal. This proved the importance of calculating 3D effects for the study site during dry and irrigation periods. Therefore, different synthetic models based on the levee geometry and water level in the canal in each period were constructed in RES2DMOD and RES3DMODx64 to quantify 3D effects for the study site. The ratios of apparent resistivity values calculated in RES3DMODx64 to the values calculated in RES2DMOD showed that 3D effects approach a maximum of 30% when the canal is empty during winter, and they arrive at a maximum of 10% when the canal is filled with water in summer. Using the graphs of the modelled 3D effects as a function of electrode spacing, apparent resistivity pseudosections measured by the permanent ERT system are corrected for 3D effects to obtain reliable resistivity sections after inversion. The final resistivity maps can be then converted into water content images using the empirical and site‐dependent relationship developed from core samples in the study area. Water content maps can be used to evaluate the stability of the levee and to detect possible seepage zones.
Phenotypic diversity of skulls in the Merovingian population (Norroy‐le‐Veneur cemetery, 7th century AD, Moselle, France) in the context of Early Medieval Europe
Authors: Šefčáková Alena , Thurzo Milan , Katina Stanislav , Velemínská Jana , Brůžek Jaroslav , Velemínský Petr
Published: June 2020

Western Europe underwent a major sociocultural and economic transformation from Late Antiquity to the Early Middle Ages. This so‐called Migration Period is characterized by invasions of various western and eastern non‐Romanized peoples, as well as by nomadic Huns. The Frankish state was the only Germanic state to successfully survive this period. Nevertheless, the arrival of unknown populations could have influenced the autochthonous Frankish population. Biological contacts between them are strongly reflected phenotypically in head/skull dimensions. The aim of this craniometric analysis of the Merovingian cemetery at Norroy‐le‐Veneur (NV), present‐day France, is to contribute to an understanding of population changes during the Migration Period. The NV data were compared, using univariate statistical analysis adapted to the state of preservation of the skulls without the use of imputation techniques, with the current database of European burials. Intersexual and interpopulation differences were tested by bootstrap two‐sample t test applied to winsorized measurements, indices and their z scores. Overall, NV is similar in terms of skull shape to the other Merovingian cemeteries. Males have significantly longer ultradolichocephalic skulls than dolichocephalic females and greater biauricular width. NV is significantly different to burials in present‐day Hungary, its individuals having significantly longer skulls, wider faces and wider skulls in the biauricular region. The NV individuals have significantly higher values of biauricular width than people from burials in Austria and Czechia‐Bohemia and lower length‐width index values than individuals from burials in Moravia (skulls are longer).

The different shape of the skulls from Hungarian territory in the Early Middle Ages is due to the arrival of the Huns and Near‐Eastern Sarmat‐Alan populations, characterized by shorter and wider skulls, in the Carpathian Basin. The results suggest that they probably did not interfere too much genotypically in western European regions and did not significantly affect the Germanic Franks.
Glutaredoxin AtGRXS8 represses transcriptional and developmental responses to nitrate in Arabidopsis thaliana roots
Authors: Ehrary Ahmad , Rosas Miguel , Carpinelli Sophia , Davalos Oscar , Cowling Craig , Fernandez Francisco , Escobar Matthew
Published: June 2020

Glutaredoxins (GRXs) are small oxidoreductase enzymes that can reduce disulfide bonds in target proteins. The class III GRX gene family is unique to land plants, and Arabidopsis thaliana has 21 class III GRXs, which remain largely uncharacterized. About 80% of A. thaliana class III GRXs are transcriptionally regulated by nitrate, and several recent studies have suggested roles for these GRXs in nitrogen signaling. Our objective was to functionally characterize two nitrate‐induced GRX genes, AtGRXS5 and AtGRXS8, defining their roles in signaling and development in the A. thaliana root. We demonstrated that AtGRXS5 and AtGRXS8 are primarily expressed in root and shoot vasculature (phloem), and that the corresponding GRX proteins display nucleo‐cytosolic subcellular localization. Ectopic expression of AtGRXS8 in transgenic plants caused major alterations in root system architecture: Normal primary root development, but a near absence of lateral roots. RNA sequencing demonstrated that the roots of AtGRXS8‐overexpressing plants show strongly reduced transcript abundance for many primary nitrate response genes, including the major high‐affinity nitrate transporters. Correspondingly, high‐affinity nitrate uptake and the transport of nitrate from roots to shoots are compromised in AtGRXS8‐overexpressing plants. Finally, we demonstrated that the AtGRXS8 protein can physically interact with the TGA1 and TGA4 transcription factors, which are central regulators of early transcriptional responses to nitrate in A. thaliana roots. Overall, these results suggest that AtGRXS8 acts to quench both transcriptional and developmental aspects of primary nitrate response, potentially by interfering with the activity of the TGA1 and TGA4 transcription factors.
Dose equivalency and efficacy of biosimilar erythropoietin stimulating agents: Data from real clinical practice
Authors: Gaipov Abduzhappar , Issanov Alpamys , Mursalova Zhanar , Tulegenova Nazia , Kakim Zoya , Baizakov Mukhit , Tuganbekova Saltanat , Aljofan Mohamad
Published: June 2020

Recently, biosimilar erythropoietin stimulating agents become available in Kazakhstan. Important properties of the biosimilar such as dose equivalency to the original medicine (originator) and the ability to maintain hemoglobin target levels remain insufficiently described in many clinical settings. Thus, the current study aims to determine dose equivalency and hemoglobin target levels in a cohort of dialysis patients who were switched from the originator to biosimilar. Retrospective data of 74 patients from different dialysis centers who received at least 6 months of originator and switched to biosimilar and had at least 6 months follow‐up were analyzed. The clinical data of 32 male and 42 female patients were collected. The mean age was 52.5 ± 13.5 years. There is no significant difference in mean levels of hemoglobin during pre‐switching from originator to biosimilar (6 months prior) and post switching period (9 months after). Additionally, a subgroup analysis of 59 patients who received originator (epoetin beta), 6 months before the switch, showed similar level of hemoglobin (110.7 ± 14 vs 113.2 ± 10 g/L, P = .05) 6 months after the switch to biosimilar (epoetin zeta) at the equivalent dose regimen (69.5 ± 29 vs 68.1 ± 30 IU/kg/wk, P = .55). However, after 9 months of switching, patients using lower doses of biosimilar (69.5 ± 29 vs 63.3 ± 30 IU/kg/wk, P < .01), showed significantly higher levels of hemoglobin (110.7 ± 14 vs 114.7 ± 8 g/L, P = .01) compared to preswitching period. In conclusion, long‐term use of lower doses of biosimilar managed to maintain hemoglobin within the target levels.
Bayesian optimal phase II clinical trial design with time‐to‐event endpoint
Authors: Zhou Heng , Chen Cong , Sun Linda , Yuan Ying
Published: June 2020

We propose a Bayesian optimal phase II (BOP2) design for clinical trials with a time‐to‐event endpoint (eg, progression‐free survival [PFS]) or co‐primary endpoints consisted of a time‐to‐event endpoint and a categorical endpoint (eg, PFS and toxicity). We use an exponential‐inverse gamma model to model the time to event. At each interim, the go/no‐go decision is made by comparing the posterior probabilities of the event of interest with an adaptive probability cutoff. The BOP2 design is flexible in the number of interim looks and applicable to both single‐arm and two‐arm trials. The design maximizes the power for detecting effective treatments, with a well‐controlled type I error, thereby bridging the gap between Bayesian designs and frequentist designs. The BOP2 design is easy to implement. Its stopping boundary can be enumerated and included in study protocol before the onset of the trial for single‐arm studies. Simulation studies show that the BOP2 design has favorable operating characteristics, with higher power and lower risk of incorrectly terminating the trial than some Bayesian phase II designs. The software to implement the BOP2 design will be freely available at www.trialdesign.org.
A physically based raindrop–cloud droplet accretion parametrization for use in bulk microphysics schemes
Authors: Ahmed Tanvir , Jin Han‐Gyul , Baik Jong‐Jin
Published: June 2020

The accretion process in bulk cloud microphysics schemes can be parametrized using the stochastic collection equation (SCE). In this study, the collection efficiency of each raindrop–cloud droplet pair is applied to the SCE to derive a new accretion parametrization that considers a strong variability of accretion rate depending on the cloud droplet and raindrop size distributions. To evaluate the new accretion parametrization (NP), it is implemented into a cloud‐resolving model, replacing the original accretion parametrization (OP) based on the continuous collection equation. In the idealized simulations of deep convective clouds, NP predicts overall larger accretion rates and smaller autoconversion rates than OP. The resultant high accretion/autoconversion rate ratio in NP increases the mean raindrop size. This induces faster sedimentation of raindrops that is associated with the earlier onset of surface precipitation and also weakens the evaporation cooling of raindrops that can affect the thermodynamics and dynamics of clouds. Meanwhile, for a given pair of rainwater and cloud water mass contents, the accretion rates in NP have a broad distribution while those in OP are less variant, suggesting that the dependence of the accretion rates on bulk microphysical properties other than the mass contents also needs to be properly considered in accretion parametrizations. Most of the aforementioned differences between the two accretion parametrizations found in the idealized simulations are also found in the real‐case simulations of a precipitation event over Bangladesh but the differences are smaller, and the spatial distribution of the accumulated precipitation amount is relatively well predicted by NP compared to OP.
A new calibration technique for quantitative gas analyses of fluid inclusions using a quadrupole mass spectrometer
Authors: Pettitt Elizabeth A. , Schaller Morgan F.
Published: June 2020

Rationale

Quantitative gas analysis by quadrupole mass spectrometry is used widely in the study of fluid inclusion volatiles, but the currently available instrument calibration techniques have a number of limitations. We describe a new method to overcome these by employing custom‐machined stainless‐steel calibration volumes that fit into modified bellows valves and can be filled on the high‐vacuum prep line of the instrument. This allows the calibration gas to be introduced in a pulse‐like fashion, replicating a burst of sample gas from a ruptured fluid inclusion.

Methods

The modified bellows valves equipped with calibration volumes are loaded onto the high‐vacuum inlet of a quadrupole mass spectrometer. Cobalt‐based alloy stem tips are then used to seal calibration gases (dry air, in this case) at known pressures into the calibration volumes for analysis.

Results

Two volumes of different dimensions were used to produce a relationship between moles introduced and integrated beam area for m/z 14, 32, 40, and 44. A linear fit along with a 95% confidence band for the relationship of moles introduced and integrated beam area was determined for the purpose of quantitative gas analysis in fluid inclusions containing atmospheric air. The calibration curves for each m/z have R‐squared (COD) values of 0.94 or better. For validation of this calibration technique, measurements were made using outside air as an unknown.

Conclusions

A new calibration technique has been developed for measuring femto‐ to pico‐mole quantities of atmospheric air that greatly reduces contamination and introduces calibration gas in a pulse similar to sample gas. This technique has reduced the error in quantifying these small aliquots of air to an uncertainty of ±1.5%.
Does piracy lead to product abandonment or stimulate new product development?: Evidence from mobile platform‐based developer firms
Authors: Miric Milan , Jeppesen Lars Bo
Published: June 2020

Research Summary

With the growth of digital platforms, understanding the role of property rights on those platforms has become increasingly important. Digital piracy, the unauthorized copying and distribution of digital products, is therefore an important strategic issue, both because of lost revenues and because it is thought to decrease innovation. Yet, while the latter effect is often argued, empirical evidence is limited. We study whether piracy affects innovation and whether it leads firms to shift to different types of innovations. By studying a large piracy event in a mobile app marketplace, we find that piracy leads to a decrease in the release of incremental innovations, such as bug fixes, but does not decrease more substantial revisions. Additionally, it is associated with subsequent new product development.

Managerial Abstract

For many platform companies, a critical issue is understanding how piracy and imitation should be regulated, motivated in part by a common narrative that piracy will eliminate innovation on these platforms. The present article suggests that these effects are slightly more nuanced. We find that piracy does lead to a decline in incremental innovations, such as bug fixes or appearance tweaks, but no discernible decline in more major innovations, such as feature updates or entirely new versions. This implies that piracy can shape the type of innovation, potentially leading to products that are less polished and refined but not affecting the overall level of innovation.
Directionally Selective Polyhalide Molecular Glue for Stable Inverted Perovskite Solar Cells
Authors: Piao Chengcheng , Xi Jun , Choi Mansoo
Published: June 2020

The fundamental instability of hybrid perovskite solar cells originates from the considerable halide vacancies. Furthermore, the local roles of halide vacancies between grain boundaries and grain bulk generally conflict, thus inhibiting complete passivation. To overcome this obstacle, a rational polyhalide ligand, di‐(2‐picolyl)amine triiodide, is designed as a molecular “glue” to achieve comprehensive passivation. Unlike a monohalide ligand, this ligand has multiple iodide ions and a quasiplanar tridentate chelation capability, contributing to directional passivation along the grain boundaries and overall passivation throughout the grain bulk. Using this molecular glue passivation, the best inverted solar cell yields an efficiency of 20.02%. Moreover, the relative stability of this cell in ambient air (≈40% humidity, 800 h aging) and under light‐soaking conditions (500 h aging) is profoundly enhanced by 33.33% and 22.26%, respectively. Herein, important insights into the design of passivating molecules to achieve low‐defect perovskites toward the development of multifunctional devices are provided.
Reflection as meta‐action: Lesson study and EFL teacher professional development
Authors: Uştuk Özgehan , De Costa Peter I.
Published: June 2020

This article explores the nature of reflective practice in a professional development process based on lesson study. The authors examine how a lesson study model initiates reflection as a meta‐action scaffolding reflective practice among teachers of English as a foreign language (EFL) at a university in Turkey. Fieldnotes, interviews, and audio diaries were used to collect both introspective and retrospective data. These data sources enabled the researchers to focus on reflective action both as a process and as a product. Using thematic content analysis, the research demonstrates how reflective practice permeates lesson study as teachers reflect on their practice both individually and collaboratively. Moreover, the research also shows how teacher agency can be promoted in reflective practice throughout lesson study. The findings reveal how reflection as meta‐action in lesson study can support transformative teacher agency among EFL teachers.
Precipitation Variability in West Africa in the Context of Global Warming and Adaptation Recommendations
Authors: Quenum Gandome Mayeul L. D. , Klutse Nana A. B. , Alamou Eric A. , Lawin Emmanuel A. , Oguntunde Philip G.
Published: June 2020

It is commonly accepted that the Earth’s climate is changing and will continue to change in the future. Rising temperatures are one of the direct indicators of global climate change. To investigate how the rising global temperature will affect the spatial pattern of rainfall in West Africa, the precipitation and potential evapotranspiration variables from ten Global Climate Models (GCMs) under the RCP8.5 scenario were driven by the Rossby Centre regional atmospheric model (RCA4) from the COordinated Regional Climate Downscaling EXperiment (CORDEX) and analyzed at four specific global warming levels (GWLs) (i.e., 1.5 °C, 2.0 °C, 2.5 °C, and 3.0 °C) above the preindustrial level. This study utilized three indices, the precipitation concentration index (PCI), the precipitation concentration degree (PCD), and the precipitation concentration period (PCP) over West Africa to explore the spatiotemporal variations in the characteristics of precipitation concentrations. Besides, the analysis of the effect of the specified GWLs on the Consecutive Dry Days (CDD), Consecutive Wet Days (CWD), and frequency of the intense rainfall events allowed to a better understanding of the spatial and temporal patterns of extreme precipitation in West Africa. Results reveal that, for the projections simulations and at each GWL, the rainfall onset starts one month earlier in the Gulf of Guinea in response to the control period. To encourage adaptation to the various changes in climate in general, and particularly in respect of rainfall, this study proposes several adaptation methods that can be implemented at the local (country) level, as well as some mitigation and adaptation strategies at the regional (West African) level.
Simulation-Based Assessment Methods
Authors: van der Meer A. A. , Bhandia R. , Palensky P. , Cvetković M. , Widl E. , Nguyen V. H. , Tran Q. T. , Heussen K.
Published: June 2020

This chapter provides a brief overview of modelling and simulation approaches for smart grid systems. A special focus is put onto the coupling of simulation environments; i.e., the co-simulation of power systems and its components. Furthermore, selected implementations of standardized interfaces for domain simulators covering the domains of power systems and ICT are presented.
Summary and Outlook
Authors: Strasser T. I. , de Jong E. C. W. , Sosnina M.
Published: June 2020

This chapters briefly summarizes the main achievements and contributions of the ERIGrid project related to validation and testing methods and concepts for Cyber-Physical Energy System (CPES) systems. Also, an outlook about necessary future research and development work by addressing smart energy systems needs are outlined.
Loop equation and exact soft anomalous dimension in $$ \mathcal{N} $$ = 4 super Yang-Mills
Authors: Giombi Simone , Komatsu Shota
Published: June 2020

Abstract

BPS Wilson loops in supersymmetric gauge theories have been the subjects of active research since they are often amenable to exact computation. So far most of the studies have focused on loops that do not intersect. In this paper, we derive exact results for intersecting 1/8 BPS Wilson loops in

$$ \mathcal{N} $$

N

= 4 supersymmetric Yang-Mills theory, using a combination of supersymmetric localization and the loop equation in 2d gauge theory. The result is given by a novel matrix-model-like representation which couples multiple contour integrals and a Gaussian matrix model. We evaluate the integral at large N , and make contact with the string worldsheet description at strong coupling. As an application of our results, we compute exactly a small-angle limit (and more generally near-BPS limits) of the cross anomalous dimension which governs the UV divergence of intersecting Wilson lines. The same quantity describes the soft anomalous dimension of scattering amplitudes of W -bosons in the Coulomb branch.
dS spaces and brane worlds in exotic string theories
Authors: Blumenhagen Ralph , Brinkmann Max , Makridou Andriana , Schlechter Lorenz , Traube Matthias
Published: June 2020

Abstract

We investigate string-phenomenological questions of Hull’s exotic superstring theories with Euclidean strings/branes and multiple times. These are known to be plagued by pathologies like the occurrence of ghosts. On the other hand, these theories exhibit de Sitter solutions. Our special focus lies on the question of the coexistence of such de Sitter solutions and ghost-free brane worlds. To this end, the world-sheet CFT description of Euclidean fundamental strings is generalized to include also the open string/D-brane sector. Demanding that in the “observable” gauge theory sector the gauge fields themselves are non-ghosts, a generalization of the dS swampland conjecture is found.
Domains Without Dense Steklov Nodal Sets
Authors: Bruno Oscar P. , Galkowski Jeffrey
Published: June 2020

This article concerns the asymptotic geometric character of the nodal set of the eigenfunctions of the Steklov eigenvalue problem $$\begin{aligned} -\Delta \phi _{\sigma _j}=0,\quad \hbox { on }\,\,\Omega ,\quad \partial _\nu \phi _{\sigma _j}=\sigma _j \phi _{\sigma _j}\quad \hbox { on }\,\,\partial \Omega \end{aligned}$$-Δϕσj=0,onΩ,∂νϕσj=σjϕσjon∂Ωin two-dimensional domains $$\Omega $$Ω. In particular, this paper presents a dense family $$\mathcal {A}$$A of simply-connected two-dimensional domains with analytic boundaries such that, for each $$\Omega \in \mathcal {A}$$Ω∈A, the nodal set of the eigenfunction $$\phi _{\sigma _j}$$ϕσj “is not dense at scale $$\sigma _j^{-1}$$σj-1”. This result addresses a question put forth under “Open Problem 10” in Girouard and Polterovich (J Spectr Theory 7(2):321–359, 2017). In fact, the results in the present paper establish that, for domains $$\Omega \in \mathcal {A}$$Ω∈A, the nodal sets of the eigenfunctions $$\phi _{\sigma _j}$$ϕσj associated with the eigenvalue $$\sigma _j$$σj have starkly different character than anticipated: they are not dense at any shrinking scale. More precisely, for each $$\Omega \in \mathcal {A}$$Ω∈A there is a value $$r_1>0$$r1>0 such that for each j there is $$x_j\in \Omega $$xj∈Ω such that $$\phi _{\sigma _j}$$ϕσj does not vanish on the ball of radius $$r_1$$r1 around $$x_j$$xj.
Towards control of cellulose biosynthesis by Komagataeibacter using systems-level and strain engineering strategies: current progress and perspectives
Authors: Ryngajłło Małgorzata , Jędrzejczak-Krzepkowska Marzena , Kubiak Katarzyna , Ludwicka Karolina , Bielecki Stanisław
Published: June 2020

The strains of the Komagataeibacter genus have been shown to be the most efficient bacterial nanocellulose producers. Although exploited for many decades, the studies of these species focused mainly on the optimisation of cellulose synthesis process through modification of culturing conditions in the industrially relevant settings. Molecular physiology of Komagataeibacter was poorly understood and only a few studies explored genetic engineering as a strategy for strain improvement. Only since recently the systemic information of the Komagataeibacter species has been accumulating in the form of omics datasets representing sequenced genomes, transcriptomes, proteomes and metabolomes. Genetic analyses of the mutants generated in the untargeted strain modification studies have drawn attention to other important proteins, beyond those of the core catalytic machinery of the cellulose synthase complex. Recently, modern molecular and synthetic biology tools have been developed which showed the potential for improving targeted strain engineering. Taking the advantage of the gathered knowledge should allow for better understanding of the genotype–phenotype relationship which is necessary for robust modelling of metabolism as well as selection and testing of new molecular engineering targets. In this review, we discuss the current progress in the area of Komagataeibacter systems biology and its impact on the research aimed at scaled-up cellulose synthesis as well as BNC functionalisation.

Key points• The accumulated omics datasets advanced the systemic understanding of Komagataeibacter physiology at the molecular level.• Untargeted and targeted strain modification approaches have been applied to improve nanocellulose yield and properties.• The development of modern molecular and synthetic biology tools presents a potential for enhancing targeted strain engineering.• The accumulating omic information should improve modelling of Komagataeibacter’s metabolism as well as selection and testing of new molecular engineering targets.
Decomposition of arrow type positive semidefinite matrices with application to topology optimization
Authors: Kočvara Michal
Published: June 2020

Decomposition of large matrix inequalities for matrices with chordal sparsity graph has been recently used by Kojima et al. (Math Program 129(1):33–68, 2011) to reduce problem size of large scale semidefinite optimization (SDO) problems and thus increase efficiency of standard SDO software. A by-product of such a decomposition is the introduction of new dense small-size matrix variables. We will show that for arrow type matrices satisfying suitable assumptions, the additional matrix variables have rank one and can thus be replaced by vector variables of the same dimensions. This leads to significant improvement in efficiency of standard SDO software. We will apply this idea to the problem of topology optimization formulated as a large scale linear semidefinite optimization problem. Numerical examples will demonstrate tremendous speed-up in the solution of the decomposed problems, as compared to the original large scale problem. In our numerical example the decomposed problems exhibit linear growth in complexity, compared to the more than cubic growth in the original problem formulation. We will also give a connection of our approach to the standard theory of domain decomposition and show that the additional vector variables are outcomes of the corresponding discrete Steklov–Poincaré operators.
The (Broad-Sense) Genetic Correlations Among Four Measures of Inattention and Hyperactivity in 12 Year Olds
Authors: Dolan Conor V. , de Zeeuw Eveline L. , Zayats Tetyana , van Beijsterveldt C. E. M. , Boomsma Dorret I.
Published: June 2020

We estimated the genetic covariance matrix among four inattention (INATT) and four hyperactivity (HYP) measures in the classical twin design. Data on INATT and HYP symptom counts were obtained in mono- and dizygotic twin pairs (N = 1593) with an average age of 12.2 years (sd = .51). We analyzed maternal ratings of INATT and HYP based on the Conners’ Parent Rating Scale (CPRS), the Strengths and Weaknesses of ADHD-symptoms and Normal-behavior (SWAN), and teacher ratings based on the Conners' Teacher rating scale (CTRS) and the ASEBA Teacher Rating Form (TRF). Broad-sense heritabilities, corrected for the main effects of sex and for random teacher rater effects, were large (ranging from .658 to .912). The results reveal pervasive and strong broad-sense genetic effects on INATT and HYP phenotypes with the phenotypic covariance among the phenotypes largely due to correlated genetic effects. Specifically between 79.9 and 99.9% of the phenotypic covariance among the HYP measures, and between 81.0 and 93.5% of the INATT measures are attributable to broad-sense genetic effects. Overall, the present results, pertaining to the broad-sense heritabilities and shared genetic effects, support the current genome-wide association meta-analytic approach to identifying pleiotropic genetic variants.
Atypical Sensory Processing Profiles and Their Associations With Motor Problems In Preschoolers With Developmental Coordination Disorder
Authors: Mikami Misaki , Hirota Tomoya , Takahashi Michio , Adachi Masaki , Saito Manabu , Koeda Shuhei , Yoshida Kazutaka , Sakamoto Yui , Kato Sumi , Nakamura Kazuhiko , Yamada Junko
Published: June 2020

The aims of this study were to identify sensory processing profiles specific to preschoolers with DCD in a community sample and examine the association of sensory processing problems with motor coordination difficulties in these children. Sixty-three 5-year-old children with DCD and without other neurodevelopmental disorders and 106 age-matched typically developing children participated in this study. Sensory processing problems were assessed using the Sensory Profile. Our results demonstrated problems in wide sensory processing patterns (low registration, sensitivity and avoiding) and areas (auditory, vestibular, touch and oral) in children with DCD compared with typically developing children. Additionally, the association of problems in sensory processing patterns (sensitivity and avoiding) and areas (touch and auditory) with motor coordination difficulties were identified in children with DCD alone. Our findings indicate that sensory processing abnormalities may contribute to the pathophysiology of DCD, suggesting the importance of assessing sensory processing functions in children with DCD.
Photosynthesis, carbon acquisition and primary productivity of phytoplankton: a review dedicated to Colin Reynolds
Authors: Dokulil Martin T. , Qian Kuimei
Published: June 2020

The review intends to give an overview on developments, success, results of photosynthetic research and on primary productivity of algae both freshwater and marine with emphasis on more recent discoveries. Methods and techniques are briefly outlined focusing on latest improvements. Light harvesting and carbon acquisition are evaluated as a basis of regional and global primary productivity and algal growth. Thereafter, long-time series, remote sensing and river production are exemplified and linked to the potential effects of climate change. Lastly, the synthesis seeks to put the life achievements of Colin S. Reynolds into context of the subject review.