bluuebunny/crossref_metadata_2025 huggingface dataset:
Early career researchers and their authorship and peer review beliefs and practices: An international study
Authors: Jamali Hamid R. , Nicholas David , Watkinson Anthony , Abrizah Abdullah , Rodríguez‐Bravo Blanca , Boukacem‐Zeghmouri Cherifa , Xu Jie , Polezhaeva Tatiana , Herman Eti , Świgon Marzena
Published: December 2019

This article reports on the findings of an international online survey of early career researchers (ECRs) with regard to their authorship and peer review, attitudes, and practices, which sought to discover how the new wave of researchers were utilizing these key aspects of the scholarly communications system. A questionnaire was developed on the back of a 3‐year longitudinal, qualitative study and was distributed through publisher lists, social media networks, university networks, and specialist ECR membership organizations. Identical English, Polish, Russian, Chinese, Spanish, and French versions of the questionnaire were used. Results from 1,600 respondents demonstrated that 82.7% had co‐authored a paper, and most had performed a variety of authorship tasks. Almost half the respondents reported being subject to various authorship policies, although a quarter said they were not aware of any such policies. Almost all Chinese ECRs reported being subject to authorship policies, but only a third of UK ECRs reported the same. Three‐quarters of ECRs had experience in responding to peer review, and half had been peer reviewers. Half the respondents had a good experience of review and viewed it as a valuable way to improve their authorship skills. However, there was some criticism of some shortcoming such as lengthy peer review and superficial or uninformed comments by reviewers. Double‐blind review was the preferred methodology, and there were few suggestions for how to improve the review process.
Meteorological conditions induce strong shifts in mixotrophic and heterotrophic flagellate bacterivory over small spatio‐temporal scales
Authors: Anderson Ruth , Hansen Per Juel
Published: December 2019

Mixotrophic bacterivory by small phytoflagellates (SP) can equal that of heterotrophic flagellates (HF) in marine euphotic waters. Due to their differing nutritional requirements from prey, SP and HF bacterivory are thought to differentially impact nutrient and carbon cycling through microbial food webs. However, little is known on how the relative dominance of SP and HF feeding shifts along environmental gradients, especially over short spatio‐temporal scales. Here, SP and HF bacterivory rates were compared over 5 d at three depths in the upper water column of a dynamic coastal zone, through the use of surrogate prey. SP and HF bacterivory strongly fluctuated over both spatial (< 5 m) and temporal (day to day) scales despite relatively stable abundance, with a respective seven‐ and ten‐fold difference between minimum and maximum bacterivory rates. Irradiance regulated SP community bacterivory, leading to a grouping into high rates under light limitation, mid‐level rates under optimal irradiance levels for growth and low rates at very high irradiance levels. SP bacterivory only dominated over that of HF at irradiance ranges generally considered optimal for photosynthetic growth (∼ 40–300 μmol photons m−2 s−1). SP bacterivory, but not that of HF, was positively correlated to total bacterial abundance, with HF potentially selectively targeting actively growing bacteria. Overall, the present study indicates that meteorological conditions affecting irradiance levels could strongly impact microbial food web dynamics and the cycling of carbon and nutrients through coastal marine systems.
Increasing accuracy of lake nutrient predictions in thousands of lakes by leveraging water clarity data
Authors: Wagner Tyler , Lottig Noah R. , Bartley Meridith L. , Hanks Ephraim M. , Schliep Erin M. , Wikle Nathan B. , King Katelyn B. S. , McCullough Ian , Stachelek Jemma , Cheruvelil Kendra S. , Filstrup Christopher T. , Lapierre Jean Francois , Liu Boyang , Soranno Patricia A. , Tan Pang‐Ning , Wang Qi , Webster Katherine , Zhou Jiayu
Published: December 2019

Aquatic scientists require robust, accurate information about nutrient concentrations and indicators of algal biomass in unsampled lakes in order to understand and predict the effects of global climate and land‐use change. Historically, lake and landscape characteristics have been used as predictor variables in regression models to generate nutrient predictions, but often with significant uncertainty. An alternative approach to improve predictions is to leverage the observed relationship between water clarity and nutrients, which is possible because water clarity is more commonly measured than lake nutrients. We used a joint‐nutrient model that conditioned predictions of total phosphorus, nitrogen, and chlorophyll aon observed water clarity. Our results demonstrated substantial reductions (8–27%; median = 23%) in prediction error when conditioning on water clarity. These models will provide new opportunities for predicting nutrient concentrations of unsampled lakes across broad spatial scales with reduced uncertainty.
A two‐dimensional metric temporal logic
Authors: Baratella Stefano , Masini Andrea
Published: December 2019

We introduce a two‐dimensional metric (interval) temporal logic whose internal and external time flows are dense linear orderings. We provide a suitable semantics and a sequent calculus with axioms for equality and extralogical axioms. Then we prove completeness and a semantic partial cut elimination theorem down to formulas of a certain type.
Admissibility and nonuniform polynomial dichotomies
Authors: Dragičević D.
Published: December 2019

For a general one‐sided nonautonomous dynamics defined by a sequence of linear operators, we consider the notion of a polynomial dichotomy with respect to a sequence of norms and we characterize it completely in terms of the admissibility of bounded solutions. As a nontrivial application, we establish the robustness of the notion of a nonuniform polynomial dichotomy.
Synthesis and Post‐Polymerization Functionalization of Halogen‐Substituted Polyphosphinoboranes to Access Alkyne‐Functionalized Derivatives
Authors: Arz Marius I. , Knights Alastair W. , Manners Ian
Published: December 2019

Catalytic dehydropolymerization of halogen‐functionalized phosphine–boranes (4‐X‐C6H4)PH2⋅BH3 (1a: X = Br, 1b: X = I) with [CpFe(CO)2(OTf)] at 100 °C provides convenient access to halogen‐functionalized polyphosphinoboranes [(4‐X‐C6H4)PH–BH2]n (2a: X = Br, 2b: X = I). These polymers are useful precursors for post‐polymerization functionalization, which is demonstrated by Sonogashira coupling under mild conditions to yield the alkynyl‐functionalized polyphosphinoborane [(4‐PhCC‐C6H4)PH–BH2]n (3).
A method for predicting short‐time changes in fine particulate matter (PM2.5) mass concentration based on the global navigation satellite system zenith tropospheric delay
Authors: Guo Min , Zhang Hanwei , Xia Pengfei
Published: December 2019

In this study, a method of haze prediction has been developed based on zenith tropospheric delay (ZTD). The relationship between ZTD and fine particulate matter (PM2.5, the main component of haze) during hazy periods in Beijing from 2015 to 2018 was analysed. The correlation between ZTD and the PM2.5 series was analysed based on data from three hazy periods with relatively stable weather conditions, no heavy rainfall and relatively continuous data, and the correlation coefficient between ZTD and the PM2.5 series was maintained in the range [0.5207, 0.7883]. The analysis showed a strong correlation between them based on data from three hazy periods with relatively stable weather conditions. To enhance the correlation between ZTD and the PM2.5 sequence, the standard orthogonal wavelet Daubechies (db5) method was used in this research. By removing the influence of the high frequency signal using the method, the ZTD and PM2.5 sequences were reconstructed using the fourth‐layer low frequency coefficients, their correlation coefficient was maintained in the range [0.5540, 0.9067] and the percentage range of the correlation coefficient was increased to [2.46, 16.69]. Finally, the reconstructed PM2.5, ZTD, relative humidity, average wind speed and NO2 series through db5 were used to establish a multiple regression model to predict the change in the PM2.5 mass concentration. The experimental results show that the multivariate regression model after wavelet analysis is superior to the traditional multivariate regression method in predicting the short‐term change of PM2.5 through four statistics values (R2, F, P, S2) of the regression model and that it is effective and feasible for predicting short‐term haze.
Mutations in PDLIM5 are rare in dilated cardiomyopathy but are emerging as potential disease modifiers
Authors: Verdonschot Job A. J. , Robinson Emma L. , James Kiely N. , Mohamed Mohamed W. , Claes Godelieve R. F. , Casas Kari , Vanhoutte Els K. , Hazebroek Mark R. , Kringlen Gabriel , Pasierb Michele M. , van den Wijngaard Arthur , Glatz Jan F. C. , Heymans Stephane R. B. , Krapels Ingrid P. C. , Nahas Shareef , Brunner Han G. , Szklarczyk Radek
Published: December 2019

Background

A causal genetic mutation is found in 40% of families with dilated cardiomyopathy (DCM), leaving a large percentage of families genetically unsolved. This prevents adequate counseling and clear recommendations in these families. We aim to identify novel genes or modifiers associated with DCM.

Methods

We performed computational ranking of human genes based on coexpression with a predefined set of genes known to be associated with DCM, which allowed us to prioritize gene candidates for their likelihood of being involved in DCM. Top candidates will be checked for variants in the available whole‐exome sequencing data of 142 DCM patients. RNA was isolated from cardiac biopsies to investigate gene expression.

Results

PDLIM5 was classified as the top candidate. An interesting heterozygous variant (189_190delinsGG) was found in a DCM patient with a known pathogenic truncating TTN‐variant. The PDLIM5 loss‐of‐function (LoF) variant affected all cardiac‐specific isoforms of PDLIM5 and no LoF variants were detected in the same region in a control cohort of 26,000 individuals. RNA expression of PDLIM5 and its direct interactors (MYOT, LDB3, and MYOZ2) was increased in cardiac tissue of this patient, indicating a possible compensatory mechanism. The PDLIM5 variant cosegregated with the TTN‐variant and the phenotype, leading to a high disease penetrance in this family. A second patient was an infant with a homozygous 10 kb‐deletion of exon 2 in PDLIM5 resulting in early‐onset cardiac disease, showing the importance of PDLIM5 in cardiac function.

Conclusions

Heterozygous PDLIM5 variants are rare and therefore will not have a major contribution in DCM. Although they likely play a role in disease development as this gene plays a major role in contracting cardiomyocytes and homozygous variants lead to early‐onset cardiac disease. Other environmental and/or genetic factors are probably necessary to unveil the cardiac phenotype in PDLIM5 mutation carriers.
Stability and bifurcation analysis of a nutrient‐phytoplankton model with time delay
Authors: Guo Qing , Dai Chuanjun , Yu Hengguo , Liu He , Sun Xiuxiu , Li Jianbing , Zhao Min
Published: December 2019

We proposed a nutrient‐phytoplankton interaction model with a discrete and distributed time delay to provide a better understanding of phytoplankton growth dynamics and nutrient‐phytoplankton oscillations induced by delay. Standard linear analysis indicated that delay can induce instability of a positive equilibrium via Hopf bifurcation. We derived the conditions guaranteeing the existence of Hopf bifurcation and tracked its direction and the stability of the bifurcating periodic solutions. We also obtained the sufficient conditions for the global asymptotic stability of the unique positive steady state. Numerical analysis in the fully nonlinear regime showed that the stability of the positive equilibrium is sensitive to changes in delay values under select conditions. Numerical results were consistent with results predicted by linear analysis.
Maximum likelihood activity and attenuation estimation using both emission and transmission data with application to utilization of Lu‐176 background radiation in TOF PET
Authors: Cheng Li , Ma Tianyu , Zhang Xuezhu , Peng Qiyu , Liu Yaqiang , Qi Jinyi
Published: December 2019

Purpose

We present a new method for joint reconstruction of activity and attenuation images using both emission and transmission data and demonstrate its advantage over the standard maximum likelihood activity and attenuation (MLAA) reconstruction using emission data alone.

Methods

We define a joint likelihood function including both time‐of‐flight (TOF) emission data and transmission data. The latter can be obtained from an external source or from Lu‐176 background radiation. Activity and attenuation images are estimated jointly by maximizing the likelihood function. The proposed method solves the undetermined scale problem in the conventional MLAA. A monotonically convergent algorithm was derived to optimize the objective function. Furthermore, we present a theoretical analysis of the noise propagation in the joint reconstruction. Simulations and phantom experiments were conducted to validate the feasibility of the proposed method.

Results

Quantitatively correct and less noisy images were reconstructed with the proposed method. Artifacts in the attenuation map reconstructed from the standard MLAA were removed by incorporating transmission data. Noise analysis was validated with different transmission sources and transmission count levels. The theoretical prediction indicated that noise of activity map would not change in a large range of transmission count level and a very low transmission count level could result in good estimation.

Conclusions

The results demonstrate the feasibility of obtaining quantitatively correct images in TOF PET by using both emission and (weak) transmission data. The noise analysis also provides guidance for choosing a proper transmission source configuration to reduce noise propagation.
A calcium‐mediated actin redistribution at egg activation in Drosophila
Authors: York‐Andersen Anna H. , Hu Qinan , Wood Benjamin W. , Wolfner Mariana F. , Weil Timothy T.
Published: December 2019

Egg activation is the essential process in which mature oocytes gain the competency to proceed into embryonic development. Many events of egg activation are conserved, including an initial rise of intracellular calcium. In some species, such as echinoderms and mammals, changes in the actin cytoskeleton occur around the time of fertilization and egg activation. However, the interplay between calcium and actin during egg activation remains unclear. Here, we use imaging, genetics, pharmacological treatment, and physical manipulation to elucidate the relationship between calcium and actin in living Drosophila eggs. We show that, before egg activation, actin is smoothly distributed between ridges in the cortex of the dehydrated mature oocytes. At the onset of egg activation, we observe actin spreading out as the egg swells though the intake of fluid. We show that a relaxed actin cytoskeleton is required for the intracellular rise of calcium to initiate and propagate. Once the swelling is complete and the calcium wave is traversing the egg, it leads to a reorganization of actin in a wavelike manner. After the calcium wave, the actin cytoskeleton has an even distribution of foci at the cortex. Together, our data show that calcium resets the actin cytoskeleton at egg activation, a model that we propose to be likely conserved in other species.
Correcting time‐intensity curves in dynamic contrast‐enhanced breast MRI for inhomogeneous excitation fields at 7T
Authors: van Rijssel Michael J. , Pluim Josien P. W. , Chan Hui‐Shan M. , van den Wildenberg Lieke , Schmitz Alexander M. Th. , Luijten Peter R. , Gilhuijs Kenneth G. A. , Klomp Dennis W. J.
Published: December 2019

Purpose

Inhomogeneous excitation at ultrahigh field strengths (7T and above) compromises the reliability of quantified dynamic contrast‐enhanced breast MRI. This can hamper the introduction of ultrahigh field MRI into the clinic. Compensation for this non‐uniformity effect can consist of both hardware improvements and post‐acquisition corrections. This paper investigated the correctable radiofrequency transmit () range post‐acquisition in both simulations and patient data for 7T MRI.

Methods

Simulations were conducted to determine the minimum level at which corrections were still beneficial because of noise amplification. Two correction strategies leading to differences in noise amplification were tested. The effect of the corrections on a 7T patient data set (N = 38) with a wide range of levels was investigated in terms of time‐intensity curve types as well as washin, washout and peak enhancement values.

Results

In simulations assuming a common amount of T1 saturation, the lowest level at which the SNR of the corrected images was at least that of the original precontrast image was 43% of the nominal angle. After correction, time‐intensity curve types changed in 24% of included patients, and the distribution of curve types corresponded better to the distribution found in literature. Additionally, the overlap between the distributions of washin, washout, and peak enhancement values for grade 1 and grade 2 tumors was slightly reduced.

Conclusion

Although the correctable range varies with the amount of T1 saturation, post‐acquisition correction for inhomogeneous excitation was feasible down to levels of 43% of the nominal angle in vivo.
On the magnetic field dependence of deuterium metabolic imaging
Authors: de Graaf Robin A. , Hendriks Arjan D. , Klomp Dennis W.J. , Kumaragamage Chathura , Welting Dimitri , Arteaga de Castro Catalina S. , Brown Peter B. , McIntyre Scott , Nixon Terence W. , Prompers Jeanine J. , De Feyter Henk M.
Published: December 2019

Deuterium metabolic imaging (DMI) is a novel MR‐based method to spatially map metabolism of deuterated substrates such as [6,6'‐2H2]‐glucose in vivo. Compared with traditional 13C‐MR‐based metabolic studies, the MR sensitivity of DMI is high due to the larger 2H magnetic moment and favorable T1 and T2 relaxation times. Here, the magnetic field dependence of DMI sensitivity and transmit efficiency is studied on phantoms and rat brain postmortem at 4, 9.4 and 11.7 T. The sensitivity and spectral resolution on human brain in vivo are investigated at 4 and 7 T before and after an oral dose of [6,6'‐2H2]‐glucose. For small animal surface coils (Ø 30 mm), the experimentally measured sensitivity and transmit efficiency scale with the magnetic field to a power of +1.75 and −0.30, respectively. These are in excellent agreement with theoretical predictions made from the principle of reciprocity for a coil noise‐dominant regime. For larger human surface coils (Ø 80 mm), the sensitivity scales as a +1.65 power. The spectral resolution increases linearly due to near‐constant linewidths. With optimal multireceiver arrays the acquisition of DMI at a nominal 1 mL spatial resolution is feasible at 7 T.
A general mass lumping scheme for the variants of the extended finite element method
Authors: Asareh Iman , Song Jeong‐Hoon , Mullen Robert L. , Qian Yu
Published: December 2019

A new strategy for the mass matrix lumping of enriched elements for explicit transient analysis is presented. It is shown that to satisfy the kinetic energy conservation, the use of zero or negative masses for enriched degrees of freedom of lumped mass matrix may be necessary. For a completely cracked element, by lumping the mass of each side of the interface into the finite element nodes located at the same side and assigning zero masses to the enriched degrees of freedom, the kinetic energy for rigid body translations is conserved without transferring spurious energy across the interface. The time integration is performed by adopting an explicit‐implicit technique, where the regular and enriched degrees of freedom are treated explicitly and implicitly, respectively. The proposed method can be viewed as a general mass lumping scheme for the variants of the extended finite element methods because it can be used irrespective of the enrichment method. It also preserves the optimal critical time step of an intact finite element by treating the enriched degrees of freedom implicitly. The accuracy and efficiency of the proposed mass matrix are validated with several benchmark examples.
An investigation of a wash‐durable solar energy harvesting textile
Authors: Satharasinghe Achala , Hughes‐Riley Theodore , Dias Tilak
Published: December 2019

This work demonstrates a novel and sustainable energy solution in the form of a photovoltaic fabric that can deliver a reliable energy source for wearable and mobile devices. The solar fabric was woven using electronic yarns created by embedding miniature crystalline silicon solar cells connected with fine copper wires within the fibres of a textile yarn. This approach of integrating solar energy harvesting capability within the heart of the textile fabric allows it to retain the flexibility, three‐dimensional deformability, and moisture and heat transfer characteristics of the fabric. In this investigation, both the design and performance of the solar cell embedded yarns and solar energy harvesting fabrics were explored. These yarns and resultant fabrics were characterised under different light intensities and at different angles of incident light, a critical factor for a wearable device. The solar cell embedded yarns woven into fabrics can undergo domestic laundering and maintained ~90% of their original power output after 15 machine wash cycles. The solar fabric embedded with 200 solar cells demonstrated here (44.5 mm × 45.5 mm active area) was capable of continuously generating ~2.15 mW/cm2 under one sun illumination and was capable of powering a basic mobile phone. The power generation capability and durability of the solar energy harvesting fabric proved its viability to power wearable devices as an integral part of regular clothing.
The use of biologic therapies for the management of pediatric asthma
Authors: Lovinsky‐Desir Stephanie
Published: December 2019

With better understanding of the role of type 2 inflammation in allergic asthma, there has been progress made in the development of new biologic therapies targeting these specific pathways. This review will consider diagnostic criteria for using biologic therapies for pediatric asthma with special emphasis on populations that are likely to benefit the most from particular therapies. With the exception of the anti‐immunoglobulin E, omalizumab, very few studies have been published on the efficacy and safety of biologic therapies in children, particularly anti‐interleukin‐5 (IL5) and anti‐IL4/IL13 therapies. The review will highlight the scarcity of published data in pediatric‐specific populations. In addition, we will consider the cost‐effectiveness as well as potential long‐term consequences of biologic therapies in pediatric asthma.
Experimental and Simulation Study on Glass Transition Temperatures of GAP with Ionic‐Liquid‐Based Energetic Plasticizers
Authors: Jafari Najmeh , Arab Behrouz , Zekri Negar , Fareghi‐Alamdari Reza
Published: December 2019

Molecular dynamics (MD) simulations and experiments were carried out to study the glass transition temperature of glycidyl azide polymer (GAP) which is widely used in propellants as an energetic binder. A modification method was applied to improve the mechanical properties of GAP at low temperatures, through the addition of energetic ionic liquid plasticizers to the polymer matrix. The design and simulate under the COMPASS force field, with the ensembles of constant particle number, pressure, temperature (NPT) done. The variation of density and free volume of polymers was observed with decreasing the temperature, and the glass transition temperatures (Tg) were estimated based on the variation of density and free volume vs. temperature. Simulation and experimental results revealed that the addition of energetic ionic liquid plasticizer to the polymer matrix reduced Tg. Also, by changing the anion of ionic liquid, the size of the molecule and the number of atoms, the value of Tg was changed. The variations were 235 K (GAP), 233 K (GAP/IL‐N3), 230 K (GAP/IL‐NO3) and 214 K (GAP/IL–DCA).
Non‐Shock Ignition Probability of Octahydro‐1,3,5,7‐Tetranitro‐Tetrazocine‐Based Polymer Bonded Explosives Based on Microcrack Stochastic Distribution
Authors: Liu Rui , Chen Pengwan , Zhang Xiaotian , Zhu Shunpeng
Published: December 2019

We investigate stochastic microcracks of a heterogeneous microstructure as the primary mechanism determining the non‐shock ignition probability of octahydro‐1,3,5,7‐tetranitro‐1,2,3,5‐tetrazocine‐based polymer‐bonded explosives. To quantify the ignition probability, we modify the viscoelastic cracking constitutive model by considering randomly distributed microcracks and combine this model with the hot‐spot model and the Monte Carlo method. This method is validated by using a standard Steven test simulation, and we quantify how the microcrack stochasticity affects the ignition probability. The high‐temperature region clearly changes compared with the case of single microcrack size. The discrepancy in the mechanical response of each element due to the heterogeneous microcracks causes a shear deformation, which increases the temperature. The difference between a uniform distribution and a normal distribution in microcrack size is also discussed. For a given impact velocity, the ignition probability for the normal microcrack size distribution exceeds that for the uniform microcrack size distribution. Although the two distributions have the same mean and variance, the real range in microcrack size corresponding to the normal distribution exceeds that for the uniform distribution. The results show that the sample radius does not significantly affect the ignition probability, whereas the opposite is true for the sample thickness. The ignition‐probability curve is obtained in these cases. For sample dimensions of φ70 mm×13 mm, φ98 mm×13 mm, φ140 mm×13 mm, and φ98 mm×26 mm, the impact velocity thresholds corresponding to ignition probabilities in the range 0 %–99 % are 41.0–43.7, 41.0–44.3, 40.0–44.6, and 62.0–67.2 m/s, respectively, which is consistent with experimental results.
Measurement of adherence to home‐based exercises among community‐dwelling stroke survivors in India
Authors: Mahmood Amreen , Solomon John Michael , English Coralie , Bhaskaran Unnikrishnan , Menon Girish , Manikandan Natarajan
Published: December 2019

Objectives

To develop an adherence questionnaire specific to stroke and measure the level of adherence to home‐based exercises among community‐dwelling stroke survivors.

Methods

We developed and validated the “Stroke‐Specific Measure of Adherence to Home‐based Exercises” (SS‐MAHE). We measured the exercise adherence among 92 community‐dwelling stroke survivors in a cross‐sectional study.

Results

The SS‐MAHE has two sections covering (a) the dosage of prescribed exercises and (b) dosage of actual exercises done by the participants. It was found to be reliable with ICC score of 0.81 (95% CI, 0.44, 0.94, p = .001.) Adherence was measured by comparing prescribed exercises to the actual exercises performed at home. We rated participants as “adherent” if they were following more than 70% of the prescribed exercise dosage. In our sample of 92 stroke survivors, only 28% of participants were adherent to prescribed home‐based exercises.

Conclusion

SS‐MAHE is a practical and reliable tool to measure adherence to home‐based exercises after a stroke. Exercise adherence among stroke survivors is less than ideal. There is a need for strategies to specifically target exercise adherence in stroke survivors.
Proposal of an Embedded Nanogap Biosensor by a Graphene Nanoribbon Field‐Effect Transistor for Biological Samples Detection
Authors: Anvarifard Mohammad K. , Ramezani Zeinab , Amiri Iraj Sadegh
Published: December 2019

Herein, it is examined how a graphene nanoribbon field‐effect transistor (GNRFET) can be a useful nanoscale device, along with how to use an embedded nanogap inside a top gate oxide to form a biosensor. A streptavidin–biotin binding system with the dielectric constant of 2.1 is considered as a biological test sample for detection. Introducing the biological sample to the nanogap without a buffer solution modifies the electrostatic modulation in the graphene sheet, resulting in a change in the drain current. The order of change in the drain current is considered a criterion to measure the sensitivity of the proposed biosensor. A detailed investigation and discussion of the biasing conditions during the detection process reveal the optimal bias for the proposed biosensor to achieve a greater sensitivity, all while maintaining a desirable electrical performance.
The role of secondary cyclones and cyclone families for the North Atlantic storm track and clustering over western Europe
Authors: Priestley Matthew D. K. , Dacre Helen F. , Shaffrey Len C. , Schemm Sebastian , Pinto Joaquim G.
Published: December 2019

Secondary cyclones are those that form in association with a pre‐existing primary cyclone, typically along a trailing cold front. In previously studied cases they have been shown to cause extreme damage across Europe, particularly when multiple cyclones track over the same location in rapid succession (known as cyclone clustering). To determine the dynamical relationship between primary and secondary cyclones over the North Atlantic, a frontal identification algorithm is partnered with a cyclone identification method to objectively identify secondary cyclones in 35 extended winter periods using reanalysis data. Cyclones are grouped into “cyclone families” consisting of a single primary cyclone and one or more secondary cyclones. This paper aims to quantify the differences between secondary and primary cyclones over the North Atlantic, and how cyclone families contribute to episodes of cyclone clustering across western Europe. Secondary cyclones are shown to occur most frequently in the central and eastern North Atlantic, whereas primary cyclones are commonly found over the western North Atlantic. Cyclone families have their strongest presence over the North Atlantic Ocean and contribute more than 50% of cyclones over the main North Atlantic storm track. A final category, solo cyclones, which are not associated with cyclogenesis on any connected fronts, are most commonly identified over continental regions as well as the Mediterranean Sea. Primary cyclones are associated with the development of an environment that is favourable for secondary cyclone growth. Enhanced Rossby wave breaking following primary cyclone development leads to an increase in the upper‐level jet speed and a decrease in low‐level stability. Secondary cyclogenesis commonly occurs in this region of anomalously low stability, close to the European continent. During periods of cyclone clustering, secondary cyclones are responsible for approximately 50% of the total number of cyclones. The increase in jet speed and decrease in static stability initiated by the primary cyclones acts to concentrate the genesis region of secondary cyclones and direct the cyclones that form along a similar track. While there is an increase in the secondary cyclogenesis rate near western Europe during periods of European clustering, the basin‐wide secondary cyclogenesis rate decreases during these periods. Thus the large‐scale environment redistributes secondary cyclones during periods of clustering rather than increasing the total number of secondary cyclones.
On the turbulence structure of deep katabatic flows on a gentle mesoscale slope
Authors: Stiperski Ivana , Holtslag Albert A. M. , Lehner Manuela , Hoch Sebastian W. , Whiteman C. David
Published: December 2019

A comprehensive analysis of the turbulence structure of relatively deep midlatitude katabatic flows (with jet maxima between 20 and 50 m) developing over a gentle (1°) mesoscale slope with a long fetch upstream of the Meteor Crater in Arizona is presented. The turbulence structure of flow below the katabatic jet maximum shows many similarities with the turbulence structure of shallower katabatic flows, with decreasing turbulence fluxes with height and almost constant turbulent Prandtl number. Still stark differences occur above the jet maximum where turbulence is suppressed by strong stability, is anisotropic and there is a large sub‐mesoscale contribution to the flux. Detecting the stable boundary‐layer top depends on the method used (flux‐ vs. anisotropy‐profiles) but both methods are highly correlated. The top of the stable boundary layer, however, mostly deviates from the jet maximum height or the top of the near‐surface inversion. The flat‐terrain formulations for the boundary‐layer height correlate well with the detected top of the stable boundary layer if the near‐surface and not the background stratification is used in their formulations; however, they mostly largely overestimate this boundary‐layer height. The difference from flat‐terrain boundary layers is also shown through the dependence of size of the dominant eddy with height. In katabatic flows the eddy size is semi‐constant with height throughout the stable boundary‐layer depth, whereas in flat terrain, eddy size varies significantly with height. Flux‐gradient and flux‐variance relationships show that turbulence data from different stable boundary‐layer scaling regimes collapse on top of each other showing that the dominant dependence is not on the scaling regime but on the local stability.
Foehn–cold pool interactions in the Inn Valley during PIANO IOP2
Authors: Haid M. , Gohm A. , Umek L. , Ward H. C. , Muschinski T. , Lehner L. , Rotach M. W.
Published: December 2019

A case‐study is presented of a south foehn emanating from the Wipp Valley, Austria, which encountered a cold‐air pool (CAP) in the Inn Valley near the city of Innsbruck. The analysis is based on data collected during the second Intensive Observation Period of the Penetration and Interruption of Alpine Foehn (PIANO) field experiment. Foehn was initiated on 3 November 2017 by an eastward moving trough and terminated in the afternoon of 5 November 2017 by a cold front passage. On two occasions, reversed foehn flow deflected at the mountain ridge north of Innsbruck penetrated to the bottom of the Inn Valley. The first breakthrough occurred in the afternoon of 4 November 2017. It was transient and locally limited to the northwest of the city. The second (final) breakthrough occurred in the morning of 5 November 2017 and was recorded by all surface stations in the vicinity of Innsbruck. It started with a foehn air intrusion to the northeast of Innsbruck and continued with the westward propagation of the foehn–CAP boundary along the valley. Subsequently observed northerly winds above the city were caused by an atmospheric rotor. A few hours later and prior to the cold front passage, the CAP pushed back and lifted the foehn air from the ground. During both nights, shear flow instabilities formed at the foehn–CAP interface, which resulted in turbulent heating of the CAP and cooling of the foehn. However, this turbulent heating/cooling was partly compensated by other mechanisms. Especially in the presence of strong spatial CAP heterogeneity during the second night, heating in the CAP was most likely overcompensated by negative horizontal temperature advection.
Mendelian randomization using semiparametric linear transformation models
Authors: Huang Yen‐Tsung
Published: December 2019

Mendelian randomization (MR) uses genetic information as an instrumental variable (IV) to estimate the causal effect of an exposure of interest on an outcome in the presence of unknown confounding. We are interested in the causal effect of cigarette smoking on lung cancer survival, which is subject to confounding by underlying pulmonary functions. Despite the well‐developed IV analyses for the continuous and binary outcomes, the scarcity of methodology for the survival outcome limits its utility for the time‐to‐event data collected in many observational studies. We propose an IV analysis method in the survival context, estimating causal effects on a transformed survival time and survival probabilities using semiparametric linear transformation models. We study the conditions under which hazard ratio and the effect on survival probability can be approximated. For statistical inference, we construct estimating equations to circumvent the difficulty in deriving joint likelihood of the exposure and the outcome, due to the unknown confounding. Asymptotic properties of the proposed estimators are established without parametric assumptions about confounders. We study the finite sample performance in extensive simulation studies. The MR analysis of a lung cancer study suggests a harmful prognostic effect of smoking pack‐years that would have been missed by the crude association.
Synthesis of an Ion‐Imprinted Degreasing Cotton for the Selective Removal of Cu2+ from Aqueous Solutions
Authors: Wang Pei , Tang Xu , Hu Lingquan , Yin Yankun , Chen Shaohua , Wang Hua , Wu Jing
Published: December 2019

A novel ion‐imprinted degreasing cotton (IIC) was synthesized using a surface imprinting technique for the efficient selective adsorption of Cu2+ from aqueous solutions. The morphological structure of the samples was characterized by Scanning Electron Microscopy (SEM), and the chemical modification steps were characterized by Fourier Transform Infrared Spectroscopy (FTIR). The maximum adsorption capacity of the IIC and non‐imprinted degreasing cotton (NIC) for Cu2+ was 41.49 mg/g and 19.17 mg/g, respectively, at the optimum pH value of 6. The kinetics studies demonstrated that the adsorption follows a pseudo‐second‐order kinetic model. The dsorption isotherm analysis indicated that the Langmuir adsorption isotherm fits well with the adsorption equilibrium data. Also, the competitive studies show that the IIC has a good selectivity for Cu2+. In addition, the assessment of the reusability of a the IIC was tested for five successive cycles revealed no significant decrease of the adsorption capacity.
Leveraging Research on Informal Learning to Inform Policy on Promoting Early STEM
Authors: Hurst Michelle A. , Polinsky Naomi , Haden Catherine A. , Levine Susan C. , Uttal David H.
Published: December 2019

In recent decades, educators and policymakers in the United States have increased their focus on Science, Technology, Engineering, and Mathematics (STEM) learning opportunities both in school and in informal learning environments outside of school. Informal STEM learning can take place in varied settings and involves a variety of STEM domains (e.g., engaging in engineering practices in a construction exhibit at a museum; talking about math during book reading at home). Here we provide a selective review of the literature on informal STEM learning to illustrate how these educational experiences are crucial for efforts to increase early STEM learning even before children reach school age. Leveraging cognitive and learning science research to inform policy, we make three recommendations to advance the impact of informal STEM learning: 1) integrate cognitive and learning science–based learning practices into informal learning contexts, 2) increase accessibility and diversity of informal STEM experiences, and 3) create explicit connections and coherence between formal and informal STEM learning opportunities in early childhood education.
How The Social Interactions in Communities affect the Fear of Crime
Authors: Pulido Cristian , Prieto Jeisson , Gómez Francisco
Published: December 2019

Fear of crime (FoC) refers to the subjective risk assessment of being a crime victim and the magnitude of its consequences. FoC emerges as a social construct, which is highly dependent on various psychological, cultural, and social factors. Mathematical models for the emergence and diffusion of information related to FoC relies on sequential and random interactions among persons. However, these interactions seem to be simultaneous and conditioned to members of particular social groups. Recent evidence suggests that in other spreading phenomena, the topology of the underlying network that supports individual communication may influence the community member's opinions. This paper studies how the FoC changes with preferential interaction between persons defined by a network with community structure. These particular networks are typical of many unequal societies. The results indicate that even if these supporting structures allow efficient communication, in the case of FoC propagation, this particular structure may promote an isolation effect of the FoC for the different communities. This isolation effect is higher for communities with low susceptibility to crime. Therefore, groups with low susceptibility to crime have higher feelings of security than groups with high susceptibility to crime when considering interactions in communities.
Countable Sofic Shifts with a Periodic Direction
Authors: Törmä Ilkka
Published: December 2019

As a variant of the equal entropy cover problem, we ask whether all multidimensional sofic shifts with countably many configurations have SFT covers with countably many configurations. We answer this question in the negative by presenting explicit counterexamples. We formulate necessary conditions for a vertically periodic shift space to have a countable SFT cover, and prove that they are sufficient in a natural (but quite restricted) subclass of shift spaces.
Quantitative PET imaging of PD-L1 expression in xenograft and syngeneic tumour models using a site-specifically labelled PD-L1 antibody
Authors: Christensen Camilla , Kristensen Lotte K. , Alfsen Maria Z. , Nielsen Carsten H. , Kjaer Andreas
Published: December 2019

Purpose

Despite remarkable clinical responses and prolonged survival across several cancers, not all patients benefit from PD-1/PD-L1 immune checkpoint blockade. Accordingly, assessment of tumour PD-L1 expression by immunohistochemistry (IHC) is increasingly applied to guide patient selection, therapeutic monitoring, and improve overall response rates. However, tissue-based methods are invasive and prone to sampling error. We therefore developed a PET radiotracer to specifically detect PD-L1 expression in a non-invasive manner, which could be of diagnostic and predictive value.

Methods

Anti-PD-L1 (clone 6E11, Genentech) was site-specifically conjugated with DIBO-DFO and radiolabelled with 89Zr (89Zr-DFO-6E11). 89Zr-DFO-6E11 was optimized in vivo by longitudinal PET imaging and dose escalation with excess unlabelled 6E11 in HCC827 tumour-bearing mice. Specificity of 89Zr-DFO-6E11 was evaluated in NSCLC xenografts and syngeneic tumour models with different levels of PD-L1 expression. In vivo imaging data was supported by ex vivo biodistribution, flow cytometry, and IHC. To evaluate the predictive value of 89Zr-DFO-6E11 PET imaging, CT26 tumour-bearing mice were subjected to external radiation therapy (XRT) in combination with PD-L1 blockade.

Results

89Zr-DFO-6E11 was successfully labelled with a high radiochemical purity. The HCC827 tumours and lymphoid tissue were identified by 89Zr-DFO-6E11 PET imaging, and co-injection with 6E11 increased the relative tumour uptake and decreased the splenic uptake. 89Zr-DFO-6E11 detected the differences in PD-L1 expression among tumour models as evaluated by ex vivo methods. 89Zr-DFO-6E11 quantified the increase in PD-L1 expression in tumours and spleens of irradiated mice. XRT and anti-PD-L1 therapy effectively inhibited tumour growth in CT26 tumour-bearing mice (p < 0.01), and the maximum 89Zr-DFO-6E11 tumour-to-muscle ratio correlated with response to therapy (p = 0.0252).

Conclusion

PET imaging with 89Zr-DFO-6E11 is an attractive approach for specific, non-invasive, whole-body visualization of PD-L1 expression. PD-L1 expression can be modulated by radiotherapy regimens and 89Zr-DFO-6E11 PET is able to monitor these changes and predict the response to therapy in an immunocompetent tumour model.
Does the Porter formula hold its promise? A weight estimation formula for macrosomic fetuses put to the test
Authors: Weiss Christoph , Enengl Sabine , Enzelsberger Simon Hermann , Mayer Richard Bernhard , Oppelt Peter
Published: December 2019

Purpose

Estimating fetal weight using ultrasound measurements is an essential task in obstetrics departments. Most of the commonly used weight estimation formulas underestimate fetal weight when the actual birthweight exceeds 4000 g. Porter et al. published a specially designed formula in an attempt to improve detection rates for such macrosomic infants. In this study, we question the usefulness of the Porter formula in clinical practice and draw attention to some critical issues concerning the derivation of specialized formulas of this type.

Methods

A retrospective cohort study was carried out, including 4654 singleton pregnancies with a birthweight ≥ 3500 g, with ultrasound examinations performed within 14 days before delivery. Fetal weight estimations derived using the Porter and Hadlock formulas were compared.

Results

Of the macrosomic infants, 27.08% were identified by the Hadlock formula, with a false-positive rate of 4.60%. All macrosomic fetuses were detected using the Porter formula, with a false-positive rate of 100%; 99.96% of all weight estimations using the Porter formula fell within a range of 4300 g ± 10%. The Porter formula only provides macrosomic estimates.

Conclusions

The Porter formula does not succeed in distinguishing macrosomic from normal-weight fetuses. High-risk fetuses with a birthweight ≥ 4500 g in particular are not detected more precisely than with the Hadlock formula. For these reasons, we believe that the Porter formula should not be used in clinical practice. Newly derived weight estimation formulas for macrosomic fetuses must not be based solely on a macrosomic data set.
Fault tolerant control for nonlinear systems using sliding mode and adaptive neural network estimator
Authors: Qi Haiying , Shi Yiran , Li Shoutao , Tian Yantao , Yu Ding-Li , Gomm J. B.
Published: December 2019

This paper proposes a new fault tolerant control scheme for a class of nonlinear systems including robotic systems and aeronautical systems. In this method, a sliding mode control is applied to maintain system stability under the post-fault dynamics. A neural network is used as on-line estimator to reconstruct the change rate of the fault and compensate for the impact of the fault on the system performance. The control law and the neural network learning algorithms are derived using the Lyapunov method, so that the neural estimator is guaranteed to converge to the fault change rate, while the entire closed-loop system stability and tracking control is guaranteed. Compared with the existing methods, the proposed method achieved fault tolerant control for time-varying fault, rather than just constant fault. This greatly expands the industrial applications of the developed method to enhance system reliability. The main contribution and novelty of the developed method is that the system stability is guaranteed and the fault estimation is also guaranteed for convergence when the system subject to a time-varying fault. A simulation example is used to demonstrate the design procedure and the effectiveness of the method. The simulation results demonstrated that the post-fault is stable and the performance is maintained.