bluuebunny/crossref_metadata_2025 huggingface dataset:
Migration and transformation of cadmium in rice - soil under different nitrogen sources in polymetallic sulfide mining areas
Authors: Zhang Xiaoxia , Zhang Xuexia , Lv Shuji , Shi Lei , Wang Rongping
Published: February 2020

We conducted pot experiments to assess the bioavailability of cadmium (Cd) in contaminated rhizosphere soil and accumulation in rice organs in response to nitrogen (N) supply ((NH4)2SO4, NH4NO3, NH4Cl). The results showed that the concentration of bioavailable Cd in rice rhizosphere soil was (NH4)2SO4 treatment > NH4Cl treatment > NH4NO3 treatment at the same level of N application and growth period; the Cd concentration in rice roots was (NH4)2SO4 treatment > NH4NO3 treatment > NH4Cl treatment; and the Cd concentration in rice straw was NH4NO3 treatment > NH4Cl. The Cd concentration in rice roots, straws, and seeds at the maturity stage was (NH4)2SO4 treatment > NH4Cl treatment. With the same N fertilizer, excessive N promoted Cd accumulation in rice at later growth stages. This suggested that sulfate (SO42−) influenced Cd concentration in rice. NH4Cl application maintained a low Cd level in different rice organs with the same N level. This confirmed that NH4Cl is a safe N source for rice planting in polymetallic sulfide mining areas. The study concludes that appropriate NH4Cl levels for Cd-contaminated paddy soil with high-S-content could obtain rice grains with Cd concentrations below the food safety standards (0.2 or 0.4 mg·kg−1).
Precision wearable accelerometer contact microphones for longitudinal monitoring of mechano-acoustic cardiopulmonary signals
Authors: Gupta Pranav , Moghimi Mohammad J. , Jeong Yaesuk , Gupta Divya , Inan Omer T. , Ayazi Farrokh
Published: February 2020

Mechano-acoustic signals emanating from the heart and lungs contain valuable information about the cardiopulmonary system. Unobtrusive wearable sensors capable of monitoring these signals longitudinally can detect early pathological signatures and titrate care accordingly. Here, we present a wearable, hermetically-sealed high-precision vibration sensor that combines the characteristics of an accelerometer and a contact microphone to acquire wideband mechano-acoustic physiological signals, and enable simultaneous monitoring of multiple health factors associated with the cardiopulmonary system including heart and respiratory rate, heart sounds, lung sounds, and body motion and position of an individual. The encapsulated accelerometer contact microphone (ACM) utilizes nano-gap transducers to achieve extraordinary sensitivity in a wide bandwidth (DC-12 kHz) with high dynamic range. The sensors were used to obtain health factors of six control subjects with varying body mass index, and their feasibility in detection of weak mechano-acoustic signals such as pathological heart sounds and shallow breathing patterns is evaluated on patients with preexisting conditions.
Aqueous pKa prediction for tautomerizable compounds using equilibrium bond lengths
Authors: Caine Beth A. , Bronzato Maddalena , Fraser Torquil , Kidley Nathan , Dardonville Christophe , Popelier Paul L. A.
Published: February 2020

The accurate prediction of aqueous pKavalues for tautomerizable compounds is a formidable task, even for the most established in silico tools. Empirical approaches often fall short due to a lack of pre-existing knowledge of dominant tautomeric forms. In a rigorous first-principles approach, calculations for low-energy tautomers must be performed in protonated and deprotonated forms, often both in gas and solvent phases, thus representing a significant computational task. Here we report an alternative approach, predicting pKavalues for herbicide/therapeutic derivatives of 1,3-cyclohexanedione and 1,3-cyclopentanedione to within just 0.24 units. A model, using a single ab initio bond length from one protonation state, is as accurate as other more complex regression approaches using more input features, and outperforms the program Marvin. Our approach can be used for other tautomerizable species, to predict trends across congeneric series and to correct experimental pKavalues.
Simultaneous sensing and imaging of individual biomolecular complexes enabled by modular DNA–protein coupling
Authors: Avellaneda Mario J. , Koers Eline J. , Minde David P. , Sunderlikova Vanda , Tans Sander J.
Published: February 2020

Many proteins form dynamic complexes with DNA, RNA, and other proteins, which often involves protein conformational changes that are key to function. Yet, methods to probe these critical dynamics are scarce. Here we combine optical tweezers with fluorescence imaging to simultaneously monitor the conformation of individual proteins and their binding to partner proteins. Central is a protein–DNA coupling strategy, which uses exonuclease digestion and partial re-synthesis to generate DNA overhangs of different lengths, and ligation to oligo-labeled proteins. It provides up to 40 times higher coupling yields than existing protocols and enables new fluorescence-tweezers assays, which require particularly long and strong DNA handles. We demonstrate the approach by detecting the emission of a tethered fluorescent protein and of a molecular chaperone (trigger factor) complexed with its client. We conjecture that our strategy will be an important tool to study conformational dynamics within larger biomolecular complexes.
First-principles calculations of oxygen octahedral distortions in LaAlO3/SrTiO3(001) superlattices
Authors: Wang L. , Pan W. , Han D. , Hu W. X. , Sun D. Y.
Published: February 2020

Multiple types of oxygen octahedral distortions are found in LAO/STO(001) superlattices by using density functional theory calculations.
BOKEI: Bayesian optimization using knowledge of correlated torsions and expected improvement for conformer generation
Authors: Chan Lucian , Hutchison Geoffrey R. , Morris Garrett M.
Published: February 2020

A key challenge in conformer sampling is finding low-energy conformations using a small number of energy evaluations. By extracting patterns of correlated torsions, we improve the efficiency of Bayesian Optimization in finding optimal conformations.
The puzzling hyper-fine structure and an accurate equilibrium geometry of succinic anhydride
Authors: Jahn Michaela K. , Obenchain Daniel A. , Nair K. P. Rajappan , Grabow Jens-Uwe , Vogt Natalja , Demaison Jean , Godfrey Peter D. , McNaughton Don
Published: February 2020

The puzzling fine structure in the rotational spectrum of succinic anhydride is explained and a semiexperimental geometry calculated.
Rectifying behavior in twisted bilayer black phosphorus nanojunctions mediated through intrinsic anisotropy
Authors: Shukla Vivekanand , Grigoriev Anton , Ahuja Rajeev
Published: February 2020

We explore the possibility of using van der Waals bonded heterostructures of stacked together 2D bilayer black phosphorus (BP) for nanoscale device applications.
Indium(iii) {2}-metallacryptates assembled from 2,6-dipicolinoyl-bis(N,N-diethylthiourea)
Authors: Pham Chien Thang , Roca Jungfer Maximilian , Abram Ulrich
Published: February 2020

{2}-Metallacryptates are constructed from the self-assembly of 2,6-dipicolinoylbis(N,N-diethylthiourea) ligands and mixtures of indium(iii) chloride and chlorides of monovalent cations.
Magnesium-catalyzed hydroboration of organic carbonates, carbon dioxide and esters
Authors: Cao Xu , Wang Weifan , Lu Kai , Yao Weiwei , Xue Fei , Ma Mengtao
Published: February 2020

A magnesium(i) complex was employed as a highly efficient precatalyst for the hydroboration of carbonates and esters under mild conditions.
Highly modulated supported triazolium-based ionic liquids: direct control of the electronic environment on Cu nanoparticles
Authors: Valdebenito Cristián , Pinto Jose , Nazarkovsky Michael , Chacón Gustavo , Martínez-Ferraté Oriol , Wrighton-Araneda Kerry , Cortés-Arriagada Diego , Camarada María Belén , Alves Fernandes Jesum , Abarca Gabriel
Published: February 2020

A series of new triazolium-based supported ionic liquids (SILPs), decorated with Cu NPs, were successfully prepared and applied to the N-arylation of aryl halides with anilines.
Theory of Mind Abilities and Social Competence in Preschool Children
Authors: Shivalingaiah Shrunga Manchanapura , Ramseena Fathimath , Shareen Nafeesath
Published: February 2020

Background and Objective Theory of mind (ToM) is the ability that can be attributed to mental status beliefs, intents, emotions, proficiency, etc., to oneself and to others, and the understanding that others also have intentions, conceptions, desires, and perspectives that are different from one’s own. Daily social life depends on the ability to evaluate the behavior of other people on the basis of their mental state such as their beliefs, intentions, compassions, and goals. This study was conducted to explore the ToM abilities in preschoolers.

Methods A total of 36 preschoolers participated in the study. Two stories were narrated to the children, the classic Sally-Anne Task and the Smarty’s Task. In both the tasks, the responses of the children were scored as either true belief or false belief.

Results The results of the present study revealed mixed responses among the preschoolers. It was found that 3- to 4-year-old children had more false beliefs for both the tasks when compared with 4- to 5-year-old.

Conclusion This study highlights the importance of ToM abilities in typically growing children and other clinical population. It can be concluded that the ToM abilities were improved in typically developing children. Future studies are required to explore the higher levels of embedding of ToM, and also to incorporate it in the clinical population.
Nonorganic Hearing Loss: A Case Profile
Authors: Sarve Archana Rai , Venu Hima Pakkath , Shaju Mariya
Published: February 2020

Adults and children exhibit nonorganic hearing loss (NOHL). In children, NOHL can be due to several underlying factors. Issues of this kind if not treated on time may become risky for the child’s well-being if the underlying cause of NOHL is psychosocial and emotional. In most of the clinical settings attention is less drawn toward diagnosis and management of the root cause of NOHL. In this present article, we present the audiological profile of a 7-year-old girl with NOHL. The patient came to the department with the compliant of difficulty in hearing. Immittance results showed no abnormalities; however, reliable pure tone results could not be obtained. Subjective tests revealed bilateral hearing loss and objective assessment indicated a normal hearing. On the second visit, audiometric tests were repeated which showed normal hearing. After exclusion of neurological pathology and psychological consultation, the diagnosis of NOHL was stated and the girl was scheduled for regular appointments with a psychologist. In addition, literature on the causative factors related to NOHL has also been discussed in the present article.
Predictors of Neurological Outcome of Arterial Ischemic Stroke in Children
Authors: Aprasidze Tatia , Tatishvili Nana , Shatirishvili Teona , Lomidze Giorgi
Published: February 2020

Stroke is an important cause of mortality and morbidity in children. The aim of the study was to evaluate long-term neurological outcome in children with arterial ischemic stroke (AIS) and explore predictive factors that affect poor outcome. Fifty-six patients aged between 1 month and 17 years who were treated at M. Iashvili Children's Central Hospital, Tbilisi, Georgia, with an onset of stroke from 2007 to 2017 were included. To explore predictive factors of outcome, the following data were collected: demographic characteristics, risk factors, he presenting signs, radiological features, and presence of stroke recurrence. Neurological status at discharge and long-term neurological outcome at least 1 year after stroke was evaluated according to Pediatric Stroke Outcome Measure subscale. The reported outcome after childhood stroke was variable with long-term neurological deficits in one-third of patients (30.4%). The neurological outcome was worse in males, in patients with multiple stroke episodes, and in those with infarctions involving a combination of cortical and subcortical areas. Pediatric AIS carries the risk of long-term morbidity, and neuroimaging has a predictive influence on outcome.
Do all screw dislocations cause leakage in GaN-based devices?
Authors: Wang Jin , You Haifan , Guo Hui , Xue Junjun , Yang Guofeng , Chen Dunjun , Liu Bin , Lu Hai , Zhang Rong , Zheng Youdou
Published: February 2020

Screw dislocations are generally considered to be one of the main causes of GaN-based device leakage, but so far, nearly no reports have focused on the effects of open-core screw dislocations on device leakage currents experimentally. In this paper, we use a conductive atomic force microscope to characterize the electronic properties of threading dislocations (TDs) in the GaN layer. The full-core screw dislocations and mixed dislocations are found to provide conductive paths for device leakage currents. In terms of the contribution to device leakage currents, the edge and open-core screw dislocations have smaller effects than the full-core screw dislocations and mixed dislocations. We use isotropic linear elasticity theory and density functional theory calculations to model the core atomic structures of TDs and calculate the corresponding electronic structures. The results show that screw dislocations with full-core structures are found to introduce both deep and shallow energy states within the energy gap dispersedly, while the open-core screw dislocations and the most edge dislocations introduce only shallow energy states. The calculated electronic structures of each type of dislocation are systematically compared and correlated with experimental observations. Our findings demonstrate that full-core screw dislocations and mixed dislocations in the GaN layer have a far more detrimental impact on device leakage than edge and open-core screw dislocations.
Dynamic space-charge-controlled field emission model of current conduction in metal–insulator–semiconductor capacitors
Authors: Hiraiwa Atsushi , Horikawa Kiyotaka , Kawarada Hiroshi
Published: February 2020

A dynamic space-charge-controlled field emission (SCC-FE) model that considers temporal insulator charge variations caused by voltage stress is developed for analyzing the current conduction in insulators in the entire voltage range of measurement, yielding good agreement between experiments and simulations. The usage of prestressed samples in this analysis is essential for accurately estimating the electron affinities of insulators, yielding 1.65 and 1.93 eV as the estimates for Al2O3 films formed on GaN by atomic-layer deposition (ALD) at 200 and 450 °C, respectively, and 1.65 and 1.83 eV for those on SiO2/Si, respectively. Through the bias instability analysis using the method developed here, the voltage-stress tolerance of both Si and GaN metal–insulator–semiconductor (MIS) capacitors with ALD Al2O3 films was found to be enhanced by the high-temperature (450 °C) ALD. The analysis also revealed the fact that the voltage-stress-induced flatband voltage shift of GaN capacitors with the high-temperature Al2O3 films is mainly caused by the Al2O3 charges near the substrate, hence providing a clue to even better bias stability of the GaN capacitors. With possible applications to other wide-bandgap semiconductor (WBGS) capacitors, the dynamic SCC-FE analysis developed here will play an essential role in analyzing not only gate insulator characteristics but also many reliability issues of various WBGS MIS field-effect transistors.
Polymer-bonded anisotropic SrFe12O19 filaments for fused filament fabrication
Authors: Huber Christian , Cano Santiago , Teliban Iulian , Schuschnigg Stephan , Groenefeld Martin , Suess Dieter
Published: February 2020

In this publication, we describe the extrusion process and the properties of polymer-bonded anisotropic SrFe12O19 filaments for fused filament fabrication (FFF). Highly filled polyamide 12 filaments with a filling fraction from 40 vol. % to 55 vol. % are mixed and extruded into filaments with a diameter of 1.75 mm. Such filaments are processable with a conventional FFF 3D printer. No modifications of the 3D printer are necessary. Detailed mechanical and magnetic investigations of printed samples are performed and discussed. In the presence of an external alignment field, the Sr ferrite particles inside the PA12 matrix can be aligned along an external magnetic field. The remanence can be increased by 40% by printing anisotropic structures. For the 55 vol. % filled filament, a remanence of 212.8 mT and a coercivity of 307.4 mT are measured. The capabilities of printing magnetic anisotropic structures in a complex external field are presented with a Halbach-array arrangement. With the aim of an inverse field model, based on a finite element method, the orientation of the particles and the quality of the print can be estimated by a nondestructive method.
Exploring spatially varying relationships between forest fire and environmental factors at different quantile levels
Authors: Cao Qianqian , Zhang Lianjun , Su Zhangwen , Wang Guangyu , Guo Futao
Published: February 2020

The effect of driving factors on forest fire occurrence at various risk levels beyond average fire risk is of great interest to forest fire managers in practice. Using forest fire occurrence data collected in Fujian province, China, global quantile regression (QR) and geographically weighted quantile regression (GWQR) were applied to investigate the spatially varying relationships between forest fire and environmental factors at different quantiles (e.g. 0.50, 0.75, 0.90 and 0.99) of fire occurrence. These results indicated that: (1) at each quantile, the regression coefficients of both global QR and GWQR were negative for elevation, slope and Normalised Difference Vegetation Index, and positive for settlement density, national road density and grass cover; (2) low number of pixels with high fire occurrence in space might dramatically affect the analysis and modelling of the relationship between fire occurrence and a specific environmental factor; (3) according to GWQR, the relationships between forest fire and environmental factors significantly varied across the study area at different quantiles of fire occurrence; and (4) the GWQR models performed better in model fitting and prediction than the QR models at all quantiles. Therefore, the GWQR models could help decision makers to better plan for forest fire management and prevention strategies.
Applying the Hierarchy of Hazard Control to Regulation of Sound Levels in Entertainment Venues
Authors: Beach Elizabeth Francis , Cowan Robert , Mulder Johannes , O’Brien Ian
Published: February 2020

Excessive sound levels at events where amplified music is a central element pose a risk to hearing. Whereas noise exposure in the workplace has been recognized as a hazard for over a century, the potential harm resulting from recreational sound exposure has only become apparent in recent years. In occupational settings where sound levels are high, employers are required to implement risk-mitigation strategies to reduce sound exposure and protect employees in accordance with the hierarchy of controls. In principle, this same risk management approach can be applied to entertainment venues. In this paper we discuss how the measures stipulated in various policies and regulations aimed at protecting the hearing of audience members at entertainment venues fit within the hierarchy of controls. We compare the relative likely effectiveness of each of the measures and outline how the particular characteristics of entertainment venues impact on the practical application of these measures.
Evaluation of the progeny produced by interspecific hybridization between Camelina sativa and C. microcarpa
Authors: Tepfer Mark , Hurel Aurélie , Tellier Frédérique , Jenczewski Eric
Published: February 2020

Background and aims

Camelina (Camelina sativa, Brassicaceae) has attracted interest in recent years as a novel oilseed crop, and an increasing number of studies have sought to enhance camelina’s yield potential or to modify the composition of its oil. The ability of camelina to cross-hybridize with its wild relative, C. microcarpa, is of interest as a potential source of genetic variability for the crop.

Methods

Manual crosses were performed between the crop C. sativa and its wild relative C. microcarpa; F1 and F2 progenies were obtained. Cytology was used to study meiosis in the parents and F1s and to evaluate pollen viability. Flow cytometry was used to estimate nuclear DNA amounts and fatty acid methyl ester analysis was used to evaluate the lipid composition of F3 seeds.

Key Results

The F1 plants obtained by interspecific crossing presented severe abnormalities at meiosis and low pollen viability, and produced very few F2 seeds. The F2s presented diverse phenotypes and in some cases severe developmental abnormalities. Many F2s were aneuploid. The F2s produced highly variable numbers of F3 seeds, and certain F3 seeds presented atypical lipid profiles.

Conclusions

Considering the meiotic abnormalities observed and the probability of aneuploidy in the F2 plants, the C. microcarpa accessions used in this study would be difficult to use as sources of genetic variability for the crop.
Morphology, locomotor performance and habitat use in southern African agamids
Authors: Tan W C , Vanhooydonck B , Measey J , Herrel A
Published: February 2020

Understanding the relationships between form and function can help us to understand the evolution of phenotypic diversity in different ecological contexts. Locomotor traits are ecologically relevant as they reflect the ability of an organism to escape from predators, to catch prey or to defend territories. As such, locomotion provides a good model to investigate how environmental constraints may influence an organism’s performance. Here, we investigate the ecomorphological relationships between limb morphology, locomotor performance (sprint speed and endurance) and habitat use in six southern African agamid species. The investigated agamid species showed differences in hind limb and toe lengths. Both of these traits were further correlated with endurance capacity. This association was supported by stepwise multiple regression analyses. However, we demonstrate trade-offs in locomotor performance traits, suggesting that specialization towards speed comes at the detriment of endurance capacity. Overall, the single arboreal species studied had longer hind limbs, a higher exertion capacity and a higher mean speed. However, for a given hind limb length, the arboreal species was slower than the other habitat specialists. This study provides insights into the evolutionary mechanisms that have driven the morphological and functional evolution in southern African agamid lizards.
Targeted biologic therapy for asthma
Authors: Hynes Gareth , Pavord Ian D
Published: February 2020

Background

Asthma is a common and potentially serious condition affecting 300 million people worldwide. For many years, we have relied on a one-size-fits-all approach to its management, using corticosteroids and bronchodilators for all symptomatic patients. However, with more recent advances, it has become clear that asthma is a heterogeneous condition with multiple different underlying pathways. Understanding the different subtypes will be a key to giving us the ability to intervene in a targeted way to personalize care for patients with asthma.

Sources of data

Key published literature, guidelines and trials from clinicaltrials.gov.

Areas of agreement

The most widely studied of these subtypes is T2 high eosinophilic asthma, for which there are an increasing number of biologic therapies available. T2 high asthma is associated with the cytokines interleukin (IL)-4, IL-5 and IL-13, for each of which biologics have been developed.

Areas of controversy

It is currently unclear which of the available biologics provides superior efficacy. It is also unclear how to select which biologic for which patient.

Growing points

Head-to-head trials of the available T2 biologics will be important to determine superiority, and a suggested order for trialling biologics. Going further than this, we would like to see further analyses of available biologics to allow us to predict responders from non-responders in advance of administering therapy.

Areas timely for developing research

Non-eosinophilic T2 low asthma is an area that is under-researched and for which there are few treatments available. It is likely that there are different subtypes in this category of asthma and unravelling what these are will be crucial to developing effective treatments.
Embolization of aortic valve leaflet during valve-in-valve transcatheter aortic valve implantation: a case report
Authors: Kinthala Sudhakar , Saththasivam Poovendran , Ankam Abistanand , Sattur Sudhakar
Published: February 2020

Background 

Aortic stenosis (AS) is one of the most common valvular disorders worldwide. An increasing number of transcatheter aortic valve implantation (TAVI) procedures are being performed yearly for managing AS. This, along with the occurrence of common complications, makes timely diagnosis essential to manage rare complications and improve patient outcomes.

Case summary 

We present a case of a 77-year-old Caucasian male with severe AS with a dysfunctional bioprosthetic valve following previous surgical valve replacement. During valve-in-valve TAVI, we noted bioprosthetic valve leaflet avulsion and embolization causing a major vascular occlusion that resulted in vascular insufficiency of the left lower extremity. This condition was managed successfully via immediate diagnosis using transoesophageal echocardiogram, angiogram, and vascular surgical intervention for retrieving the embolized valve to re-establish circulation.

Discussion 

To our knowledge, this is the first case of aortic valve leaflet embolization during TAVI resulting in significant vascular insufficiency. Vascular complications are common during TAVI. However, not all vascular complications are the same. Our case highlights an embolic vascular complication from an avulsed prosthetic material during a challenging valve-in-valve TAVI procedure.
Predictors of mortality and endoscopic intervention in patients with upper gastrointestinal bleeding in the intensive care unit
Authors: Rao Vijaya L , Gupta Nina , Swei Eric , Wagner Thomas , Aronsohn Andrew , Reddy K Gautham , Sengupta Neil
Published: February 2020

Background

The outcomes of patients undergoing esophagogastroduodenoscopy (EGD) in the intensive care unit (ICU) for upper gastrointestinal bleeding (UGIB) are not well described. Our aims were to determine predictors of 30-day mortality and endoscopic intervention, and assess the utility of existing clinical-prediction tools for UGIB in this population.

Methods

Patients hospitalized in an ICU between 2008 and 2015 who underwent EGD were identified using a validated, machine-learning algorithm. Logistic regression was used to determine factors associated with 30-day mortality and endoscopic intervention. Area under receiver-operating characteristics (AUROC) analysis was used to evaluate established UGIB scoring systems in predicting mortality and endoscopic intervention in patients who presented to the hospital with UGIB.

Results

A total of 606 patients underwent EGD for UGIB while admitted to an ICU. The median age of the cohort was 62 years and 55.9% were male. Multivariate analysis revealed that predictors associated with 30-day mortality included American Society of Anesthesiologists (ASA) class (odds ratio [OR] 4.1, 95% confidence interval [CI] 2.2–7.9), Charlson score (OR 1.2, 95% CI 1.0–1.3), and duration from hospital admission to EGD (OR 1.04, 95% CI 1.01–1.07). Rockall, Glasgow-Blatchford, and AIMS65 scores were poorly predictive of endoscopic intervention (AUROC: 0.521, 0.514, and 0.540, respectively) and in-hospital mortality (AUROC: 0.510, 0.568, and 0.506, respectively).

Conclusions

Predictors associated with 30-day mortality include ASA classification, Charlson score, and duration in the hospital prior to EGD. Existing risk tools are poorly predictive of clinical outcomes, which highlights the need for a more accurate risk-stratification tool to predict the benefit of intervention within the ICU population.
Differential Gene Expression between Fungal Mating Types Is Associated with Sequence Degeneration
Authors: Ma Wen-Juan , Carpentier Fantin , Giraud Tatiana , Hood Michael E
Published: February 2020

Degenerative mutations in non-recombining regions, such as in sex chromosomes, may lead to differential expression between alleles if mutations occur stochastically in one or the other allele. Reduced allelic expression due to degeneration has indeed been suggested to occur in various sex-chromosome systems. However, whether an association occurs between specific signatures of degeneration and differential expression between alleles has not been extensively tested, and sexual antagonism can also cause differential expression on sex chromosomes. The anther-smut fungus Microbotryum lychnidis-dioicae is ideal for testing associations between specific degenerative signatures and differential expression because 1) there are multiple evolutionary strata on the mating-type chromosomes, reflecting successive recombination suppression linked to mating-type loci; 2) separate haploid cultures of opposite mating types help identify differential expression between alleles; and 3) there is no sexual antagonism as a confounding factor accounting for differential expression. We found that differentially expressed genes were enriched in the four oldest evolutionary strata compared with other genomic compartments, and that, within compartments, several signatures of sequence degeneration were greater for differentially expressed than non-differentially expressed genes. Two particular degenerative signatures were significantly associated with lower expression levels within differentially expressed allele pairs: upstream insertion of transposable elements and mutations truncating the protein length. Other degenerative mutations associated with differential expression included nonsynonymous substitutions and altered intron or GC content. The association between differential expression and allele degeneration is relevant for a broad range of taxa where mating compatibility or sex is determined by genes located in large regions where recombination is suppressed.
Tricuspid valve replacement: an appraisal of 45 years of experience
Authors: Veen Kevin M , Quanjel Thijs J M , Mokhles Mostafa M , Bogers Ad J J C , Takkenberg Johanna J M
Published: February 2020

OBJECTIVES

This study provides an overview of the change over a 45-year time period in the characteristics and outcome of patients with tricuspid valve disease undergoing surgical tricuspid valve replacement (TVR).

METHODS

The characteristics and outcomes of all consecutive TVRs from November 1972 to November 2017 at Erasmus MC were collected retrospectively. A logistic regression analysis was conducted to identify the significant predictors of 30-day mortality. Multivariable Cox regression analysis was used to identify the potential risk factors of patient outcome and the effect of time on these factors.

RESULTS

Ninety-eight patients with tricuspid valve dysfunction underwent 114 consecutive TVRs at a mean age of 50.1 ± 17.2 years (68.5% female). Aetiology changed over time from predominantly functional regurgitation (42.9% in 1972-1985) to predominantly carcinoid heart disease (47.7% in 2001-2017). Early mortality declined significantly from 35% in 1972–1985 to 6.7% in 2001–2017 (P < 0.001). Over time, the hazard ratio of late mortality decreased for higher New York Heart Association class, lower preoperative haemoglobin, and high central venous pressure and increased for the presence of preoperative leg oedema, higher creatinine and alkaline phosphatase. The late survival was 43.8% ± 5.89% at 10 years and was comparable among eras (P = 0.44). The cumulative incidence of reoperation at 10 years was 14.1% (2.3–26.0) in biological valves and 4.9% (0.1–10.3) in mechanical valves (P = 0.25).

CONCLUSIONS

Patient characteristics, potential risk factors and patient outcome changed considerably over time in patients undergoing TVR. Notably, there was a shift in aetiology, completely altering the patient population and their characteristics.
On the stability of waves in classically neutral flows
Authors: Huber Colin , Hoitt Meaghan , Barlow Nathaniel S , Hill Nicole , Keithley Kimberlee , Weinstein Steven J
Published: February 2020

This paper reports a breakdown in linear stability theory under conditions of neutral stability that is deduced by an examination of exponential modes of the form $h\approx{{e}^{i(kx-\omega t)}}$, where $h$ is a response to a disturbance, $k$ is a real wavenumber and $\omega (k)$ is a wavelength-dependent complex frequency. In a previous paper, King et al. (2016, Stability of algebraically unstable dispersive flows. Phys. Rev. Fluids, 1, 073604) demonstrates that when Im$[\omega (k)]=0$ for all $k$, it is possible for a system response to grow or damp algebraically as $h\approx{{t}^{s}}$ where $s$ is a fractional power. The growth is deduced through an asymptotic analysis of the Fourier integral that inherently invokes the superposition of an infinite number of modes. In this paper, the more typical case associated with the transition from stability to instability is examined in which Im$[\omega (k)]=0$ for a single mode (i.e. for one value of $k$) at neutral stability. Two partial differential equation systems are examined, one that has been constructed to elucidate key features of the stability threshold, and a second that models the well-studied problem of rectilinear Newtonian flow down an inclined plane. In both cases, algebraic growth/decay is deduced at the neutral stability boundary, and the propagation features of the responses are examined.
Prevalence of third-generation cephalosporin-resistant Enterobacterales colonization on hospital admission and ESBL genotype-specific risk factors: a cross-sectional study in six German university hospitals
Authors: Rohde Anna M , Zweigner Janine , Wiese-Posselt Miriam , Schwab Frank , Behnke Michael , Kola Axel , Schröder Wiebke , Peter Silke , Tacconelli Evelina , Wille Thorsten , Feihl Susanne , Querbach Christiane , Gebhardt Friedemann , Gölz Hannah , Schneider Christian , Mischnik Alexander , Vehreschild Maria J G T , Seifert Harald , Kern Winfried V , Gastmeier Petra , Hamprecht Axel
Published: February 2020

Objectives

To assess the admission prevalence of third-generation cephalosporin-resistant Enterobacterales (3GCREB) and to assess whether risk factors vary by β-lactamase genotype.

Methods

Adult patients were recruited within 72 h of admission to general wards of six university hospitals in 2014 and 2015. Rectal swabs were screened for 3GCREB and isolates were analysed phenotypically and genotypically. Patients were questioned on potential risk factors. Multivariable analyses were performed to identify risk factors for 3GCREB colonization and for specific β-lactamases.

Results

Of 8753 patients screened, 828 were 3GCREB positive (9.5%). Eight hundred and thirteen isolates were available for genotyping. CTX-M-15 was the most common ESBL (38.0%), followed by CTX-M-1 (22.5%), CTX-M-14 (8.7%), CTX-M-27 (7.5%) and SHV-ESBL (4.4%). AmpC was found in 11.9%. Interestingly, 18 Escherichia coli isolates were AmpC positive, 12 of which (67%) contained AmpC on a gene of plasmid origin [CMY (n = 10), DHA (n = 2)]. Risk factors for 3GCREB colonization varied by genotype. Recent antibiotic exposure and prior colonization by antibiotic-resistant bacteria were risk factors for all β-lactamases except CTX-M-14 and CTX-M-27. Travel outside Europe was a risk factor for CTX-M-15 and CTX-M-27 [adjusted OR (aOR) 3.49, 95% CI 2.88–4.24 and aOR 2.73, 95% CI 1.68–4.43]. A previous stay in a long-term care facility was associated with CTX-M-14 (aOR 3.01, 95% CI 1.98–4.59). A preceding hospital stay in Germany increased the risk of CTX-M-15 (aOR 1.27, 95% CI 1.14–1.41), while a prior hospital stay in other European countries increased the risk of SHV-ESBL colonization (aOR 3.85, 95% CI 1.67–8.92).

Conclusions

The detection of different ESBL types is associated with specific risk factor sets that might represent distinct sources of colonization and ESBL-specific dissemination routes.
Incidence and Prognostic Value of Acute Coagulopathy After Extensive Severe Burns
Authors: Geng Kang , Liu Yonglin , Yang Yuting , Ding Xiaobin , Tian Xinli , Liu Hongjun , Yan Hong
Published: February 2020

Acute burn-induced coagulopathy (ABIC) occurs after severe burns. However, the incidence, prognostic value, and clinical significance of ABIC after an extensive severe burn remain inconclusive due to wide variances in burn severity and coagulation profile evaluation timings in previous studies. This retrospective study explored the incidence and clinical and prognostic significance of early phase ABIC in 129 adult patients with extensive burns (>50% total body surface area [TBSA]) admitted to the burn centers of two hospitals within 10 hours postburn injury during 2009–2017. Demographics (age and sex) and clinical data (burn severity, vital signs, prehospital fluid replacement volume, hemodynamic parameters, coagulation profile, blood gas, and blood biochemical indicators) were collected upon admission. The incidence of ABIC in patients with severe burns and its relationship with their survival and clinical significance were analyzed. The average postburn interval was 5.7 ± 2.7 hours, and the incidence of ABIC was 31% (40/129). A logistic regression analysis identified ABIC as an independent predictor of 4-week severe mortality due to severe burn. The incidence of ABIC was significantly associated with the total burn area, lactic acid levels upon admission, and postburn admission interval, but not with the prehospital fluid replacement volume. In conclusion, approximately 30% of patients with severe burns developed ABIC within 10 hours postburn, and this condition strongly predicts 4-week mortality. Although burn severity and tissue ischemia/hypoxia are main risk factors for ABIC, the pathogenesis is not fully understood and should be explored in future studies.
The Transit and Light Curve Modeller
Authors: Csizmadia Sz
Published: February 2020

Transit and Light Curve Modeller (TLCM), a computer code with the purpose of analysing photometric time series of transits simultaneously with the out-of-transit light variations and radial velocity curves of transiting/eclipsing binary systems, is presented here. Joint light-curve and radial velocity fits are possible with it. The code is based on the combination of a genetic algorithm and simulated annealing. Binning, beaming, reflection, and ellipsoidal effects are included. Both objects may have their own luminosities and therefore one can use TLCM to analyse the eclipses of both exoplanet and well-detached binary systems. A simplified Rossiter–McLaughlin effect is included in the radial velocity fit, and drifts and offsets of different instruments can also be fitted. The impact of poorly known limb darkening on the Rossiter–McLaughlin effect is shortly studied. TLCM is able to manage red-noise effects via wavelet analysis. It is also possible to add parabolic or user-defined baselines and features to the code. I also predict that light variations due to beaming in some systems exhibiting radial velocity drift should be observed by, e.g. PLATO. The fit of the beaming effect is improved by invoking a physical description of the ellipsoidal effects, which has an impact on the modelling of the relativistic beaming; I also point out the difficulties that are stemming from the fact that beaming and first-order reflection effects have the same form of time dependence. Recipe is given, which describes how to analyse grazing transit events. The code is freely available.
Constraining the Einstein equivalence principle with multi-wavelength observations of polarized blazars
Authors: Yi Shuang-Xi , Zou Yuan-Chuan , Yang Xuan , Liao Bin , Wei Shao-Wen
Published: February 2020

In this paper, we present a novel method to test the Einstein equivalence principle (EEP) using (simultaneous) multi-wavelength radio observations of polarized blazars. We analyse simultaneous multi-wavelength polarization observations of 3C 279 at 22, 43, and 86 GHz obtained by two antennas of the Korean VLBI Network. We obtained 15 groups of polarization data, and applied the Metropolis–Hastings Markov chain (MHMC) to simulate the parameters when considering the EEP effect and the simplest form of Faraday rotation (single external Faraday screen). The final results show the constraint of the parametrized post-Newtonian (PPN) parameter γ discrepancy as Δγp = (1.91 ± 0.34) × 10−20. However, the single external Faraday screen is an oversimplification for blazars because there are numerous observations showing complex Faraday rotation behaviour for blazars due to internal/external Faraday dispersion, beam depolarization, etc. The Δγp results of this paper can only be considered as upper limits. Only if all other effects are revealed and considered should the result be taken as a direct measurement of the violation of the EEP.
The VIRUS-P Exploration of Nearby Galaxies (VENGA): the stellar populations and assembly of NGC 2903’s bulge, bar, and outer disc
Authors: Carrillo Andreia , Jogee Shardha , Drory Niv , Kaplan Kyle F , Blanc Guillermo , Weinzirl Tim , Song Mimi , Luo Rongxin
Published: February 2020

We study the stellar populations and assembly of the nearby spiral galaxy NGC 2903’s bulge, bar, and outer disc using the VIRUS-P Exploration of Nearby Galaxies IFS survey. We observe NGC 2903 with a spatial resolution of 185 pc using the Mitchell Spectrograph’s 4.25 arcsec fibres at the 2.7 Harlan J. Smith telescope. Bulge–bar–disc decomposition on the Two Micron All-Sky Survey (2MASS) Ks-band image of NGC 2903 shows that it has ∼6 per cent, 6 per cent, and 88 per cent, of its stellar mass in the bulge, bar, and outer disc, respectively, and its bulge has a low Sérsic index of ∼0.27, suggestive of a discy bulge. We perform stellar population synthesis and find that the outer disc has 46 per cent of its mass in stars >5 Gyr, 48 per cent in stars between 1 and 5 Gyr, and <10 per cent in younger stars. Its stellar bar has 65 per cent of its mass in ages 1–5 Gyr and has metallicities similar to the outer disc, suggestive of the evolutionary picture where the bar forms from disc material. Its bulge is mainly composed of old high-metallicity stars though it also has a small fraction of young stars. We find enhanced metallicity in the spiral arms and central region, tracing areas of high star formation as seen in the Hα map. These results are consistent with the idea that galaxies of low bulge-to-total mass ratio and low bulge Sérsic index like NGC 2903 has not had a recent major merger event, but has instead grown mostly through minor mergers and secular processes.
Phase-space structure of cold dark matter haloes inside splashback: multistream flows and self-similar solution
Authors: Sugiura Hiromu , Nishimichi Takahiro , Rasera Yann , Taruya Atsushi
Published: February 2020

Using the motion of accreting particles on to haloes in cosmological N-body simulations, we study the radial phase-space structures of cold dark matter (CDM) haloes. In CDM cosmology, formation of virialized haloes generically produces radial caustics, followed by multistream flows of accreted dark matter inside the haloes. In particular, the radius of the outermost caustic called the splashback radius exhibits a sharp drop in the slope of the density profile. Here, we focus on the multistream structure of CDM haloes inside the splashback radius. To analyse this, we use and extend the SPARTA algorithm developed by Diemer. By tracking the particle trajectories accreting on to the haloes, we count their number of apocentre passages, which is then used to reveal the multistream flows of the dark matter particles. The resultant multistream structure in radial phase space is compared with the prediction of the self-similar solution by Fillmore & Goldreich for each halo. We find that $\sim \!30{{\ \rm per\ cent}}$ of the simulated haloes satisfy our criteria to be regarded as being well fitted to the self-similar solution. The fitting parameters in the self-similar solution characterize physical properties of the haloes, including the mass accretion rate and the size of the outermost caustic (i.e. the splashback radius). We discuss in detail the correlation of these fitting parameters and other measures directly extracted from the N-body simulation.
Accelerated orbital decay of supermassive black hole binaries in merging nuclear star clusters
Authors: Ogiya Go , Hahn Oliver , Mingarelli Chiara M F , Volonteri Marta
Published: February 2020

The coalescence of supermassive black holes (SMBHs) should generate the strongest sources of gravitational waves (GWs) in the Universe. However, the dynamics of their coalescence is the subject of much debate. In this study, we use a suite of N-body simulations to follow the merger of two nuclear star clusters (NSCs), each hosting an SMBH in their centre. We find that the presence of distinct star clusters around each SMBH has important consequences for the dynamical evolution of the SMBH binary: (i) The separation between the SMBHs decreases by a few orders of magnitude in the first few Myrs by the combined effects of dynamical friction and a drag force caused by tidally stripped stars. In fact, this is a significant speedup for equal mass ratio binaries, and becomes extreme for unequal mass ratios, e.g. 1:10 or 1:100, which traditional dynamical friction alone would not permit to bind. (ii) The subsequent binary hardening is driven by the gravitational slingshots between the SMBH binary and stars, and also depends on the mass ratio between the SMBHs. Thus, with this additional drag force, we find that all SMBHs in our suite coalesce within a Hubble time. Given that about 50 per cent of Milky Way-sized galaxies host NSCs, our results are encouraging for upcoming GW observations with the Laser Interferometer Space Antenna – LISA – which will detect SMBH coalescence in the 104–107 M⊙ mass range.
Evolutionary Analysis of the Bacillus subtilis Genome Reveals New Genes Involved in Sporulation
Authors: Shi Lei , Derouiche Abderahmane , Pandit Santosh , Rahimi Shadi , Kalantari Aida , Futo Momir , Ravikumar Vaishnavi , Jers Carsten , Mokkapati Venkata R S S , Vlahoviček Kristian , Mijakovic Ivan
Published: February 2020

Bacilli can form dormant, highly resistant, and metabolically inactive spores to cope with extreme environmental challenges. In this study, we examined the evolutionary age of Bacillus subtilis sporulation genes using the approach known as genomic phylostratigraphy. We found that B. subtilis sporulation genes cluster in several groups that emerged at distant evolutionary time-points, suggesting that the sporulation process underwent several stages of expansion. Next, we asked whether such evolutionary stratification of the genome could be used to predict involvement in sporulation of presently uncharacterized genes (y-genes). We individually inactivated a representative sample of uncharacterized genes that arose during the same evolutionary periods as the known sporulation genes and tested the resulting strains for sporulation phenotypes. Sporulation was significantly affected in 16 out of 37 (43%) tested strains. In addition to expanding the knowledge base on B. subtilis sporulation, our findings suggest that evolutionary age could be used to help with genome mining.