bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization and optimization of AlGaN/GaN metal-insulator semiconductor heterostructure field effect transistors using supercritical CO2/H2O technology*
Authors: Liu Meihua , Huang Zhangwei , Chang Kuan-Chang , Lin Xinnan , Li Lei , Jin Yufeng
Published: August 2020

The impact of supercritical CO2/H2O technology on the threshold-voltage instability of AlGaN/GaN metal-insulator semiconductor high-electron-mobility transistors (MIS-HEMTs) is investigated. The MIS-HEMTs were placed in a supercritical fluid system chamber at 150 °C for 3 h. The chamber was injected with CO2 and H2O at pressure of 3000 psi (1 psi ≈ 6.895 kPa). Supercritical H2O fluid has the characteristics of liquid H2O and gaseous H2O at the same time, that is, high penetration and high solubility. In addition, OH− produced by ionization of H2O can fill the nitrogen vacancy near the Si3N4/GaN/AlGaN interface caused by high temperature process. After supercritical CO2/H2O treatment, the threshold voltage shift is reduced from 1 V to 0.3 V. The result shows that the threshold voltage shift of MIS-HEMTs could be suppressed by supercritical CO2/H2O treatment.
Improvement of the low-field-induced magnetocaloric effect in EuTiO3 compounds*
Authors: Zeng Shuang , Jiang Wen-Hao , Yang Hui , Mo Zhao-Jun , Shen Jun , Li Lan
Published: August 2020

The magnetocaloric effect of Mn, Ni, and Mn–Ni-doped EuTiO3 compounds are studied in the near-liquid-helium-temperature range. The Eu(Ti0.9375Mn0.0625)O3, Eu(Ti0.975Ni0.025)O3, and Eu(Ti0.9125Mn0.0625Ni0.025)O3 are prepared by the sol–gel method. The Eu(Ti0.9375Mn0.0625)O3 and Eu(Ti0.9125Mn0.0625Ni0.025)O3 exhibit ferromagnetism with second-order phase transition, and the Eu(Ti0.975Ni0.025)O3 displays antiferromagnetic behavior. Under the magnetic field change of 10 kOe (1 Oe = 79.5775 A⋅m−1), the values of magnetic entropy change are 8.8 J⋅kg−1⋅K−1, 12 J⋅kg−1⋅K−1, and 10.9 J⋅kg−1⋅K−1 for Eu(Ti0.9375Mn0.0625)O3, Eu(Ti0.975Ni0.025)O3, and Eu(Ti0.9125Mn0.0625Ni0.025)O3, respectively. The co-substitution of Mn and Ni can not only improve the magnetic entropy change, but also widen the refrigeration temperature window, which greatly enhances the magnetic refrigeration capacity. Under the magnetic field change of 10 kOe, the refrigerant capacity value of Eu(Ti0.9125Mn0.0625Ni0.025)O3 is 62.6 J⋅kg−1 more than twice that of EuTiO3 (27 J⋅kg−1), indicating that multi-component substitution can lead to better magnetocaloric performance.
Temperature-dependent Gilbert damping in Co2 FeAl thin films with different B2 ordering degrees*
Authors: Dunzhu Gesang , Zhao Yi-Bing , Jin Ying , Zhou Cai , Jiang Chang-Jun
Published: August 2020

The temperature-dependent Gilbert damping in Co2FeAl thin film grown on a Pb(Mg1/3Nb2/3)O3-30%PbTiO3 substrate is investigated by the systematic measurement of physical property measurement system (PPMS) on a series of samples with different substrate temperatures. Varying the substrate temperatures from 350 °C to 500 °C, the B2 ordering degrees of Co2FeAl thin films increase, which can lead the Gilbert damping to decrease, indicated by the field-sweep in-plane PPMS measurements. In addition, the measurement result of PPMS demonstrates that the Gilbert damping decreases first with measurement temperature decreasing down to about 150 K, then increases at a measurement temperature of ∼ 50 K, and decreases again with the measurement temperature decreasing. There are two independent damping manners, namely bulk damping and surface damping, which contribute to the Gilbert damping. Moreover, the observed peak of Gilbert damping at ∼ 50 K can be attributed to the spin re-orientation transition at the Co2FeAl surface, which is similar to the result of the effective magnetization as a function of measurement temperature. The result presents the evidence for further studying the Gilbert damping in Co2FeAl thin film.
The Impact of High-quality Development of China’s Economy and the Change of Industrial Structure on Energy consumption in Transportation
Authors: Wang Xuecheng , Zhang Yi
Published: August 2020

This paper explores the impact of high-quality economic development orientation and changes in China’s industrial structure on sustainable transportation development, including the impact of changes in transportation volume, transportation demand characteristics, and transportation energy consumption. the quantitative model of the relationship between macroeconomic factors like industrial structure changes with transportation demand and energy consumption is constructed. On this basis, traffic energy consumption is predicted under the future economic development scenarios. The research shows that the economic development model and the change of industrial structure are highly correlated with the energy consumption of transportation. The economic high-quality development scenario, following the corresponding change of transportation modes will increase the transportation energy consumption per transportation volumes, and the total amount transportation volumes and its energy consumption will decline.
Simplified Calculation of Energy Efficiency Index for Plate Heat Exchanger
Authors: Lu Hongliang , Ren Bin , Pu Zhe , Si Jun , Ren Facai , Du Yannan
Published: August 2020

Based on GB/T 27698.3-2011 heat exchanger and heat transfer element performance test method Part 3: Plate heat exchanger, a simplified method for the calculation of energy efficiency index is proposed other than just experimental data required by NB/T 47004.1-2017 plate heat exchangers-part 1: plate-and-frame heat exchangers. The new equation of EEI in term of 12 parameters δρ
, λρ
, lh,l
c, dh,d
c, Ch,Cc,ah, bh,ac,bc
incorporates both fitted correlations of experimental result and parameters for fluid physical properties and working conditions. Therefore, the method omits the intermediate processes such as total heat transfer coefficient k and pressure drops for both sides. It also solves the accuracy problem that deviates from the standard working conditions and is difficult to realize practically. The new test of high cost is unnecessary to obtain the energy efficiency index for old plate heat exchangers with part experimental data or correlations.
Bounds on 2-torsion in class groups of number fields and integral points on elliptic curves
Authors: Bhargava M. , Shankar A. , Taniguchi T. , Thorne F. , Tsimerman J. , Zhao Y.
Published: August 2020

We prove the first known nontrivial bounds on the sizes of the 2-torsion subgroups of the class groups of cubic and higher degree number fields

K
K

(the trivial bound being
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coming from the bound on the entire class group). This yields corresponding improvements to: (1) bounds of Brumer and Kramer on the sizes of 2-Selmer groups and ranks of elliptic curves, (2) bounds of Helfgott and Venkatesh on the number of integral points on elliptic curves, (3) bounds on the sizes of 2-Selmer groups and ranks of Jacobians of hyperelliptic curves, and (4) bounds of Baily and Wong on the number of

A
4

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-quartic fields of bounded discriminant.
Polarized human cholangiocytes release distinct populations of apical and basolateral small extracellular vesicles
Authors: Davies Brian A. , Morton Leslie O. , Jefferson John R. , Rozeveld Cody N. , Doskey Luke C. , LaRusso Nicholas F. , Katzmann David J.
Published: August 2020

Human cholangiocytes, epithelial cells that line the bile ducts, were cultured as a model with which to study polarized small extracellular vesicle (sEV) communication. These cells release distinct sEV pools to mediate communication via their apical and basolateral domains. Furthermore, defective ESCRT function may contribute to disease states through altered sEV signaling.
Temporal Changes in Cuticular Hydrocarbons During Worker-Reproductive Transition in the Eastern Subterranean Termite (Blattodea: Rhinotermitidae)
Authors: Sun Qian , Haynes Kenneth F , Zhou Xuguo
Published: August 2020

In social insects, the reproductive division of labor is often regulated through communication using cuticular hydrocarbons (CHCs) that indicate caste identity and reproductive status. In many termites, workers retain reproductive potential and can differentiate into ergatoid reproductives, and this process is mediated by the presence of reproductives in sex- and age-specific patterns. However, little is known about the variation of CHCs profiles during this transition. In this study, we analyzed the CHC profiles of workers in comparison with ergatoids of different age, sex, and mating status in the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Blattodea: Rhinotermitidae), one of the most widely distributed termite species in the world. Both female and male ergatoids were characterized by the presence of tricosane and a group of long-chain and methyl-branched hydrocarbons (chain length ≥ 33), which were found in significantly lower quantities from workers. In addition, CHC profiles differed between newly differentiated (3–4 d) and old (20–25 d) ergatoids, but no difference in CHC signatures was found between females and males based on identified compounds. Heneicosane, a previously reported royal recognition pheromone in R. flavipes, was not detected in ergatoids examined in this study. The results of caste- and age-dependent variations suggest that CHCs may act as releaser pheromones that mediate caste recognition and age-related interactions between reproductives, but analytical results of identified compounds in this study do not support CHCs as sex-specific primer pheromones that regulate nestmate fertility. Royal pheromones in termites may involve complex hydrocarbon blends and non-hydrocarbon substances that await further investigation.
Monetary value of informal caregiving in dementia from a societal perspective
Authors: Pitkala Kaisu H , Laakkonen Marja-Liisa , Kallio Eeva-Liisa , Kautiainen Hannu , Raivio Minna M , Tilvis Reijo S , Strandberg Timo E , Ohman Hannareeta
Published: August 2020

Background

Dementia is a condition which results in a high cost of care, a significant proportion of which is the cost associated with informal care. In previous studies, informal caregiving has been challenging to assess due to difficulties in estimating the true time spent on caregiving work and how to value caregivers’ time. The aim of this study was to compare the costs of dementia among patients living alone and among those living with a caregiver to show the monetary value of informal caregiving from a societal perspective.

Methods

Data from our four dementia trials using the same measures were combined, allowing the inclusion of 604 participants. Participants were followed up for 2 years or until death for their use of health and social services. Use of all services was retrieved from medical/social records. We also included the costs of lost productivity of those caregivers who were not retired.

Results

The total mean cost of services and lost productivity was €22,068/person-year (pyrs). Participants living alone had a mean cost of €45,156/pyrs, whereas those living with a spouse had a mean cost of €16,416/pyrs (mean cost ratio 2.99, 95% confidence interval 2.64–3.39). Participants living alone and having <15 Mini-Mental State Examination points had higher costs than people with dementia in institutional care.

Conclusions

Detailed data of service use and characteristics of people with dementia showed that from a societal perspective, living alone is a very strong determinant of service use in dementia. Informal caregivers do invaluable work for society.
Impact of reflex fosfomycin susceptibility testing on the utilization of carbapenems for definitive extended-spectrum β-lactamase Escherichia coli urinary tract infection treatment
Authors: Deemer Kevin , Grey Jonathan , Fronczek Christopher , Marr Kerry
Published: August 2020

Purpose

A protocol was started within a large health system to automatically test all confirmed extended-spectrum beta-lactamase (ESBL)–producing Escherichia coli urine isolates for susceptibility to fosfomycin, an antibiotic not routinely included in such testing in most institutions. This study assessed the effectiveness of the protocol at reducing carbapenem use for the definitive treatment of ESBL E. coli urinary tract infection (UTI) through several endpoints.

Methods

Eighty and 99 patients were compared pre- and postintervention, respectively. The primary outcome was the proportion of patients who received definitive carbapenem therapy. Key secondary outcomes included median total carbapenem days of therapy (DOT), discharge on intravenous UTI antibiotics, and median total antibiotic DOT.

Results

Preprotocol vs postprotocol definitive carbapenem use was seen in 59 of 80 patients (73.8%) and 71 of 99 patients (71.7%) (95% confidence interval [CI] for difference, -11.1% to 15.1%; P = 0.76). The rates of step-down to oral agents pre- and postintervention were 15 of 59 (25.4%) and 35 of 71 (49.3%) (P = 0.004). Median carbapenem DOT in those receiving carbapenems decreased from 8 to 4 days (95% CI, -5 to -1 days; P = 0.001). Median total DOT decreased from 10 to 8 days (95% CI, -3 to -1 days; P = 0.002).

Conclusion

Implementation of a laboratory policy to automatically test ESBL positive E. coli for fosfomycin susceptibility did not reduce the percentage of patients receiving at least 1 dose of carbapenem treatment. It did result in a larger percentage reduction in step-down use of intravenous antibiotics for UTI prior to discharge, reduction in carbapenem DOT, and reduction in total antibiotic DOT.
CaNDis: a web server for investigation of causal relationships between diseases, drugs and drug targets
Authors: Škrlj Blaž , Eržen Nika , Lavrač Nada , Kunej Tanja , Konc Janez
Published: August 2020

Motivation

Causal biological interaction networks represent cellular regulatory pathways. Their fusion with other biological data enables insights into disease mechanisms and novel opportunities for drug discovery.

Results

We developed Causal Network of Diseases (CaNDis), a web server for the exploration of a human causal interaction network, which we expanded with data on diseases and FDA-approved drugs, on the basis of which we constructed a disease–disease network in which the links represent the similarity between diseases. We show how CaNDis can be used to identify candidate genes with known and novel roles in disease co-occurrence and drug–drug interactions.

Availabilityand implementation

CaNDis is freely available to academic users at http://candis.ijs.si and http://candis.insilab.org.

Supplementary information

Supplementary data are available at Bioinformatics online.
Improving Instructional Fitness Requires Change
Authors: Herrera Jose , Haskew-Layton Renée E , Narayanan Madhavan , Porras-Alfaro Andrea , Jumpponen Ari , Chung Y Anny , Rudgers Jennifer A
Published: August 2020

Transmission of information has benefitted from a breathtaking level of innovation and change over the past 20 years; however, instructional methods within colleges and universities have been slow to change. In the article, we present a novel framework to structure conversations that encourage innovation, change, and improvement in our system of higher education, in general, and our system of biology education, specifically. In particular, we propose that a conceptual model based on evolutionary landscapes in which fitness is replaced by educational effectiveness would encourage educational improvement by helping to visualize the multidimensional nature of education and learning, acknowledge the complexity and dynamism of the educational landscape, encourage collaboration, and stimulate experimental thinking about how new approaches and methodology could take various fields associated with learning, to more universal fitness optima. The framework also would encourage development and implementation of new techniques and persistence through less efficient or effective valleys of death.
S-DolLion-MSVNN: A Hybrid Model for Developing the Super-Resolution Image From the Multispectral Satellite Image
Authors: Gavade Anil B , Rajpurohit Vijay S
Published: August 2020

Super-resolution offers a new image with high resolution from the low-resolution (LR) image that is highly employed for the numerous remote sensing applications. Most of the existing techniques for formation of the super-resolution image exhibit the loss of quality and deviation from the original multi-spectral LR image. Thus, this paper aims at proposing an efficient super-resolution method using the hybrid model. The hybrid model is developed using the support vector regression model and multi-support vector neural network (MSVNN), and the weights of the MSVNN is tuned optimally using the proposed algorithm. The proposed DolLion algorithm is the integration of the dolphin echolocation algorithm and lion optimization algorithm that exhibits better convergence and offers a global optimal solution. The experimentation is performed using the datasets taken from the multi-spectral scene images. The optimal and effective formation of the super-resolution image using the proposed hybrid model outperforms the existing methods, and the analysis using the second-derivative-like measure of enhancement (SDME) ensures that the proposed method is better and yields a maximum SDME of 67.6755 dB.
Metoprolol exerts a non-class effect against ischaemia–reperfusion injury by abrogating exacerbated inflammation
Authors: Clemente-Moragón Agustín , Gómez Mónica , Villena-Gutiérrez Rocío , Lalama Doménica V , García-Prieto Jaime , Martínez Fernando , Sánchez-Cabo Fátima , Fuster Valentín , Oliver Eduardo , Ibáñez Borja
Published: August 2020

Aims

Clinical guidelines recommend early intravenous β-blockers during ongoing myocardial infarction; however, it is unknown whether all β-blockers exert a similar cardioprotective effect. We experimentally compared three clinically approved intravenous β-blockers.

Methods and results

Mice undergoing 45 min/24 h ischaemia–reperfusion (I/R) received vehicle, metoprolol, atenolol, or propranolol at min 35. The effect on neutrophil infiltration was tested in three models of exacerbated inflammation. Neutrophil migration was evaluated in vitro and in vivo by intravital microscopy. The effect of β-blockers on the conformation of the β1 adrenergic receptor was studied in silico. Of the tested β-blockers, only metoprolol ameliorated I/R injury [infarct size (IS) = 18.0% ± 0.03% for metoprolol vs. 35.9% ± 0.03% for vehicle; P < 0.01]. Atenolol and propranolol had no effect on IS. In the three exacerbated inflammation models, neutrophil infiltration was significantly attenuated only in the presence of metoprolol (60%, 50%, and 70% reductions vs. vehicle in myocardial I/R injury, thioglycolate-induced peritonitis, and lipopolysaccharide-induced acute lung injury, respectively). Migration studies confirmed the particular ability of metoprolol to disrupt neutrophil dynamics. In silico analysis indicated different intracellular β1 adrenergic receptor conformational changes when bound to metoprolol than to the other two β-blockers.

Conclusions

Metoprolol exerts a disruptive action on neutrophil dynamics during exacerbated inflammation, resulting in an infarct-limiting effect not observed with atenolol or propranolol. The differential effect of β-blockers may be related to distinct conformational changes in the β1 adrenergic receptor upon metoprolol binding. If these data are confirmed in a clinical trial, metoprolol should become the intravenous β-blocker of choice for patients with ongoing infarction.
Soil P reduces mycorrhizal colonization while favors fungal pathogens: observational and experimental evidence in Bipinnula (Orchidaceae)
Authors: Mujica María Isabel , Pérez María Fernanda , Jakalski Marcin , Martos Florent , Selosse Marc André
Published: August 2020

Little is known about the soil factors influencing root-associated fungal communities in Orchidaceae. Limited evidence suggests that soil nutrients may modulate the association with orchid mycorrhizal fungi (OMF), but their influence on non-mycorrhizal fungi remains unexplored. To study how nutrient availability affects mycorrhizal and non-mycorrhizal fungi associated with the orchid Bipinnula fimbriata, we conducted a metagenomic investigation within a large population with variable soil conditions. Additionally, we tested the effect of phosphorus (P) addition on fungal communities and mycorrhizal colonization. Soil P negatively correlated with the abundance of OMF, but not with the abundance of non-mycorrhizal fungi. After fertilization, increments in soil P negatively affected mycorrhizal colonization; however, they had no effect on OMF richness or composition. The abundance and richness of pathotrophs were negatively related to mycorrhizal colonization and then, after fertilization, the decrease in mycorrhizal colonization correlated with an increase in pathogen richness. Our results suggest that OMF are affected by soil conditions differently from non-mycorrhizal fungi. Bipinnula fimbriata responds to fertilization by altering mycorrhizal colonization rather than by switching OMF partners in the short term, and the influence of nutrients on OMF is coupled with indirect effects on the whole fungal community and potentially on plant's health.
A comparison of the inhibitory activities of Lactobacillus and Bifidobacterium against Penicillium expansum and an analysis of potential antifungal metabolites
Authors: Qiao Nanzhen , Yu Leilei , Zhang Chengcheng , Wei Chaozhi , Zhao Jianxin , Zhang Hao , Tian Fengwei , Zhai Qixiao , Chen Wei
Published: August 2020

The infection of fruits by Penicillium expansum (P. expansum) do not only cause economic loss but also potentially endanger human health, especially because few biocontrol agents against this fungus have been well studied yet. In this work, to verity the antifungal activity against P. expansum of 22 Bifidobacterium and 44 Lactobacillus, dual-culture overlay assay, microtiter plate well assay and agar spot assay were successively performed. One of the strain, Bifidobacterium adolescentis (B. adolescentis) CCFM1108 exhibited the most potent inhibition ability among all tested strains. Additionally, we showed that multiple antifungal compounds produced by tested strain synergistically inhibit the growth of P. expansum, including lactic acid, acetic acid, 3-phenyllactic acid and p-hydroxyphenyllactic acid. Those active compounds mentioned were detected in the cell-free supernatant and characterized by metabolomics analysis using GC-MS. Correspondingly, B. adolescentis CCFM1108 supernatant disrupted plasma membrane integrity of the P. expansum mycelial and drastically reduced patulin production in P. expansum. The inhibitive effects of B. adolescentis CCFM1108 were also confirmed with three other P. expansum strains. The active inhibitory properties of Bifidobacterium strains, especially B. adolescentis CCFM1108, indicate that B. adolescentis can be potentially used as a novel bioagent to prevent or delay fungal spoilage on fruit.
Fault imaging at Mt Pollino (Italy) from relative location of microearthquakes
Authors: Napolitano Ferdinando , Galluzzo Danilo , Gervasi Anna , Scarpa Roberto , La Rocca Mario
Published: August 2020

Relative location of microearthquakes that occurred at Mt Pollino (Italy) from 2011 to 2013 have been analyzed with the aim of a detailed imaging of the geometry of active faults. We identified 27 clusters composed of a number of earthquakes from 9 to 33, with local magnitude in the range 0.6–2.7. The relative location shows that the distribution of hypocentres in each cluster is characterized by extension from few tens of meters to at most 350 m. For each cluster the hypocentre distribution was fitted by a plane to infer the fault orientation, and results were compared with the fault plane solutions corresponding to the focal mechanism of earthquakes of the same cluster. The comparison shows a good agreement in most of the cases. The relative location analysis, generally applied to earthquakes with similar waveform, has been improved to permit also the relative location of earthquakes characterized by not similar signals. To achieve this purpose a modified procedure that overcome the condition of very similar waveforms has been applied to estimate the time delay between first pulses of the master events. The relative location of master events of all clusters shows a precise imaging of the relative position of all analysed sources and allows also to follow with high accuracy the evolution in time of the seismic swarm within the selected periods. The hypocentre position of master events and the nearly parallel fitting planes of any clusters suggest that most of the analyzed earthquakes were produced by different patches of the same fault. The final results depict a main fault plane characterized by NW–SE strike, dip of about 35–45° and depth between 4.5 and 6.5 km b.s.l. Focal mechanisms, used also to evaluate the local stress field, are mostly of normal type with few strike slip solutions for the shallowest events. This result is in good agreement with the local tectonic stress regime that is characterized by predominant NE–SW transtension, as inferred from structural, seismological and geophysical data.
Good-Faith Rule against Abusing Process by Multiplying Action
Authors: Solis Menalco J
Published: August 2020

Investor-State tribunals are equipped with lis pendens, res judicata, abuse of process, and adverse cost orders to ensure that parties are not twice vexed for the same issue or to minimize the harm from multiplying action. When abuse of process is applied to a parallel or successive arbitration, it is considered whether the later action could have been joined, consolidated or coordinated with an earlier one and whether there is a reasonable basis for bringing a separate action. The good faith question surrounds the accused’s intent or purpose, which can be measured subjectively if there is an intent to harm or objectively in the absence of reasonable basis. Raising the question of abuse thus involves asking whether the accused acted in good faith. But where lis pendens and res judicata do not apply, there is a colorable basis for the claim and sensible grounds for advancing with separate proceedings, the claimant is within right to bring further action. The good faith element of abuse reaches the middle ground between the claimant’s interest in accessing the arbitral forum and the respondent’s interest in being free from vexation.
Distribution of Modular Symbols in ℍ3
Authors: Constantinescu Petru
Published: August 2020

We introduce a new technique for the study of the distribution of modular symbols, which we apply to the congruence subgroups of Bianchi groups. We prove that if $K$ is a quadratic imaginary number field of class number one and $\mathcal{O}_K$ is its ring of integers, then for certain congruence subgroups of $\textrm{PSL}_2(\mathcal{O}_K)$, the periods of a cusp form of weight two obey asymptotically a normal distribution. These results are specialisations from the more general setting of quotient surfaces of cofinite Kleinian groups where our methods apply. We avoid the method of moments. Our new insight is to use the behaviour of the smallest eigenvalue of the Laplacian for spaces twisted by modular symbols. Our approach also recovers the first and second moments of the distribution.
Detection of mobile genetic elements associated with antibiotic resistance in Salmonella enterica using a newly developed web tool: MobileElementFinder
Authors: Johansson Markus H K , Bortolaia Valeria , Tansirichaiya Supathep , Aarestrup Frank M , Roberts Adam P , Petersen Thomas N
Published: August 2020

Objectives

Antimicrobial resistance (AMR) in clinically relevant bacteria is a growing threat to public health globally. In these bacteria, antimicrobial resistance genes are often associated with mobile genetic elements (MGEs), which promote their mobility, enabling them to rapidly spread throughout a bacterial community.

Methods

The tool MobileElementFinder was developed to enable rapid detection of MGEs and their genetic context in assembled sequence data. MGEs are detected based on sequence similarity to a database of 4452 known elements augmented with annotation of resistance genes, virulence factors and detection of plasmids.

Results

MobileElementFinder was applied to analyse the mobilome of 1725 sequenced Salmonella enterica isolates of animal origin from Denmark, Germany and the USA. We found that the MGEs were seemingly conserved according to multilocus ST and not restricted to either the host or the country of origin. Moreover, we identified putative translocatable units for specific aminoglycoside, sulphonamide and tetracycline genes. Several putative composite transposons were predicted that could mobilize, among others, AMR, metal resistance and phosphodiesterase genes associated with macrophage survivability. This is, to our knowledge, the first time the phosphodiesterase-like pdeL has been found to be potentially mobilized into S. enterica.

Conclusions

MobileElementFinder is a powerful tool to study the epidemiology of MGEs in a large number of genome sequences and to determine the potential for genomic plasticity of bacteria. This web service provides a convenient method of detecting MGEs in assembled sequence data. MobileElementFinder can be accessed at https://cge.cbs.dtu.dk/services/MobileElementFinder/.
Replacing dietary antibiotics with 0.20% l-glutamine and synbiotics following weaning and transport in pigs
Authors: McConn Betty R , Duttlinger Alan W , Kpodo Kouassi R , Eicher Susan D , Richert Brian T , Johnson Jay S
Published: August 2020

Dietary antibiotic use has been limited in swine production due to concerns regarding antibiotic resistance. However, this may negatively impact the health, productivity, and welfare of pigs. Therefore, the study objective was to determine if combining dietary synbiotics and 0.20% l-glutamine would improve pig growth performance and intestinal health following weaning and transport when compared with traditionally used dietary antibiotics. Because previous research indicates that l-glutamine improves swine growth performance and synbiotics reduce enterogenic bacteria, it was hypothesized that supplementing diets with 0.20% l-glutamine (GLN) and synbiotics (SYN; 3 strains of Lactobacillus [1.2 × 10^9 cfu/g of strain/pig/d] + β-glucan [0.01 g/pig/d] + fructooligosaccharide [0.01 g/pig/d]) would have an additive effect and improve pig performance and intestinal health over that of dietary antibiotics. Mixed-sex pigs (N = 226; 5.86 ± 0.11 kg body weight [BW]) were weaned (19.4 ± 0.2 d of age) and transported for 12 h in central Indiana. Pigs were blocked by BW and allotted to one of two dietary treatments (5 to 6 pigs per pen): antibiotics (positive control [PC]; chlortetracycline [441 ppm] + tiamulin [38.5 ppm]), no antibiotics (negative control [NC]), GLN, SYN, or the NC diet with both the GLN and SYN additives (GLN + SYN) fed for 14 d. From day 14 post-weaning to the end of the grow-finish period, all pigs were provided common antibiotic-free diets. Data were analyzed using PROC GLIMMIX and PROC MIXED in SAS 9.4. Overall, haptoglobin was greater (P = 0.03; 216%) in NC pigs compared with PC pigs. On day 13, GLN and PC pigs tended to have reduced (P = 0.07; 75.2% and 67.3%, respectively) haptoglobin compared with NC pigs. On day 34, the jejunal goblet cell count per villi and per millimeter tended to be greater (P < 0.08; 71.4% and 62.9%, respectively) in SYN pigs compared with all other dietary treatments. Overall, jejunal mucosa tumor necrosis factor-alpha (TNFα) gene expression tended to be greater (P = 0.09; 40.0%) in NC pigs compared with PC pigs on day 34. On day 34, jejunal mucosa TNFα gene expression tended to be greater (P = 0.09; 33.3%, 41.2%, and 60.0%, respectively) in GLN pigs compared with SYN, GLN + SYN, and PC pigs. Although it was determined that some metrics of pig health were improved by the addition of GLN and SYN (i.e., haptoglobin and goblet cell count), overall, there were very few differences detected between dietary treatments and this may be related to the stress load incurred by the pigs.
Semantic Mapping of An Ottoman Fetva Compilation: EBUSSUUD Efendi’s Jurisprudence through a Computational Lens
Authors: Ergene Boğaç , Kaygun Atabey
Published: August 2020

Fetva collections are important sources for Islamic legal history. However, few scholars have considered a particular collection of fetvas or the fetvas of an individual jurist as specific areas of legal and historical exploration. Instead, most researchers use fetvas selectively and instrumentally, that is in (at best) small groups, and in their explorations of various other topics. This article proposes computational methodologies that could characterize the contents of a 6,000-fetva corpus by an important Ottoman jurist, Şeyhülislam Ebussuud Efendi (d. 1574), to reveal its substantive composition and range. The article conceptualizes a previously uncharted textual space in a way similar to how a map depicts a geographical one. By doing so, it also provides insights into Ebussuud’s jurisprudential legacy and the major socio-legal concerns and anxieties in the Ottoman Empire during the sixteenth century.
Flight Burst Duration as an Indicator of Flight Ability and Physical Fitness in Two Species of Tephritid Fruit Flies
Authors: Manoukis Nicholas C , Carvalho Lori A F N
Published: August 2020

We introduce a method to quantify flight ability and physical fitness of individual fruit flies which we term ‘Flight Burst Duration’ (FBD). This consisted of tethering individual insects by the dorsal thorax using a vacuum and measuring the length of time the insect beats its wings while suspended off a surface. Consecutive measurements with Bactrocera dorsalis Hendel (Dipera: Tephritidae) and Zeugodacus cucurbitae Coquillett (Diptera: Tephritidae) in the same day and across days indicated that a single measurement was sufficient, and that FBD was consistent and repeatable. Insects under stress from starvation displayed shorter FBD over time, and we suggest that the measure also relates to the physical condition or survival fitness of the individual. Though somewhat laborious and time-consuming, we propose that FBD can be useful for research studies requiring individual-level phenome data and for obtaining estimates quality and dispersive movement for insects.
Molecular Differentiation of Four Species of Oropsylla (Siphonaptera: Ceratophyllidae) Using PCR-Based Single Strand Conformation Polymorphism Analyses and DNA Sequencing
Authors: Thoroughgood Jessica T , Armstrong James S , White Brandon , Anstead Clare A , Galloway Terry D , Lindsay L Robbin , Shury Todd K , Lane Jeffery E , Chilton Neil B
Published: August 2020

It is often difficult to distinguish morphologically between closely related species of fleas (Siphonaptera). Morphological identification of fleas often requires microscopic examination of internal structures in specimens cleared using caustic solutions. This process degrades DNA and/or inhibits DNA extraction from specimens, which limits molecular-based studies on individual fleas and their microbiomes. Our objective was to distinguish between Oropsylla rupestris (Jordan), Oropsylla tuberculata (Baker), Oropsylla bruneri (Baker), and Oropsylla labis (Jordan & Rothschild) (Ceratophyllidae) using PCR-based single strand conformation polymorphism (SSCP) analyses and DNA sequencing. A 446 bp region of the nuclear 28S ribosomal RNA (rRNA) gene was used as the genetic marker. The results obtained for 36 reference specimens (i.e., fleas that were morphologically identified to species) revealed no intraspecific variation in DNA sequence, whereas the DNA sequences of the four species of Oropsylla differed from one another at two to six nucleotide positions. Each flea species also had a unique SSCP banding pattern. SSCP analyses were then used to identify another 84 fleas that had not been identified morphologically. DNA sequencing data confirmed the species identity of fleas subjected to SSCP. This demonstrates that PCR-SSCP combined with DNA sequencing of the 28S rRNA gene is a very effective approach for the delineation of four closely related species of flea.
Pressure balance in the multiphase ISM of cosmologically simulated disc galaxies
Authors: Gurvich Alexander B , Faucher-Giguère Claude-André , Richings Alexander J , Hopkins Philip F , Grudić Michael Y , Hafen Zachary , Wellons Sarah , Stern Jonathan , Quataert Eliot , Chan T K , Orr Matthew E , Kereš Dušan , Wetzel Andrew , Hayward Christopher C , Loebman Sarah R , Murray Norman
Published: August 2020

Pressure balance plays a central role in models of the interstellar medium (ISM), but whether and how pressure balance is realized in a realistic multiphase ISM is not yet well understood. We address this question by using a set of FIRE-2 cosmological zoom-in simulations of Milky Way-mass disc galaxies, in which a multiphase ISM is self-consistently shaped by gravity, cooling, and stellar feedback. We analyse how gravity determines the vertical pressure profile as well as how the total ISM pressure is partitioned between different phases and components (thermal, dispersion/turbulence, and bulk flows). We show that, on average and consistent with previous more idealized simulations, the total ISM pressure balances the weight of the overlying gas. Deviations from vertical pressure balance increase with increasing galactocentric radius and with decreasing averaging scale. The different phases are in rough total pressure equilibrium with one another, but with large deviations from thermal pressure equilibrium owing to kinetic support in the cold and warm phases, which dominate the total pressure near the mid-plane. Bulk flows (e.g. inflows and fountains) are important at a few disc scale heights, while thermal pressure from hot gas dominates at larger heights. Overall, the total mid-plane pressure is well-predicted by the weight of the disc gas and we show that it also scales linearly with the star formation rate surface density (ΣSFR). These results support the notion that the Kennicutt–Schmidt relation arises because ΣSFR and the gas surface density (Σg) are connected via the ISM mid-plane pressure.
Assessing the performance of LTE and NLTE synthetic stellar spectra in a machine learning framework
Authors: Bialek Spencer , Fabbro Sébastien , Venn Kim A , Kumar Nripesh , O’Briain Teaghan , Yi Kwang Moo
Published: August 2020

In the current era of stellar spectroscopic surveys, synthetic spectral libraries are the basis for the derivation of stellar parameters and chemical abundances. In this paper, we compare the stellar parameters determined using five popular synthetic spectral grids (INTRIGOSS, FERRE, AMBRE, PHOENIX, and MPIA/1DNLTE) with our convolutional neural network (CNN, StarNet). The stellar parameters are determined for six physical properties (effective temperature, surface gravity, metallicity, [α/Fe], radial velocity, and rotational velocity) given the spectral resolution, signal-to-noise ratio, and wavelength range of optical FLAMES-UVES spectra from the Gaia-ESO Survey. Both CNN modelling and epistemic uncertainties are incorporated through training an ensemble of networks. StarNet training was also adapted to mitigate differences between the synthetic grids and observed spectra by augmenting with realistic observational signatures (i.e. resolution matching, wavelength sampling, Gaussian noise, zeroing flux values, rotational and radial velocities, continuum removal, and masking telluric regions). Using the FLAMES-UVES spectra for FGK-type dwarfs and giants as a test set, we quantify the accuracy and precision of the stellar label predictions from StarNet. We find excellent results over a wide range of parameters when StarNet is trained on the MPIA/1DNLTE synthetic grid, and acceptable results over smaller parameter ranges when trained on the 1DLTE grids. These tests also show that our CNN pipeline is highly adaptable to multiple simulation grids.
Enhanced optical activity 12 d before X-ray activity, and a 4 d X-ray delay during outburst rise, in a low-mass X-ray binary
Authors: Goodwin A J , Russell D M , Galloway D K , Baglio M C , Parikh A S , Buckley D A H , Homan J , Bramich D M , in’t Zand J J M , Heinke C O , Kotze E J , de Martino D , Papitto A , Lewis F , Wijnands R
Published: August 2020

X-ray transients, such as accreting neutron stars, periodically undergo outbursts, thought to be caused by a thermal-viscous instability in the accretion disc. Usually outbursts of accreting neutron stars are identified when the accretion disc has undergone an instability, and the persistent X-ray flux has risen to a threshold detectable by all sky monitors on X-ray space observatories. Here, we present the earliest known combined optical, UV, and X-ray monitoring observations of the outburst onset of an accreting neutron star low-mass X-ray binary (LMXB) system. We observed a significant, continuing increase in the optical i′-band magnitude starting on July 25, 12 d before the first X-ray detection with Swift/XRT and NICER (August 6), during the onset of the 2019 outburst of SAX J1808.4−3658. We also observed a 4 d optical to X-ray rise delay, and a 2 d UV to X-ray delay, at the onset of the outburst. We present the multiwavelength observations that were obtained, discussing the theory of outbursts in X-ray transients, including the disc instability model, and the implications of the delay. This work is an important confirmation of the delay in optical to X-ray emission during the onset of outbursts in LMXBs, which has only previously been measured with less sensitive all sky monitors. We find observational evidence that the outburst is triggered by ionization of hydrogen in the disc.
Kinematics of RR Lyrae stars in the Galactic bulge with OGLE-IV and Gaia DR2
Authors: Du Hangci , Mao Shude , Athanassoula E , Shen Juntai , Pietrukowicz Pawel
Published: August 2020

We analyse the kinematics and spatial distribution of 15 599 fundamental-mode RR Lyrae (RRL) stars in the Milky Way bulge by combining OGLE-IV photometric data and Gaia DR2 proper motions. We show that the longitudinal proper motions and the line-of-sight velocities can give similar results for the rotation in the Galactic central regions. The angular velocity of bulge RRLs is found to be around 35 km s−1 kpc−1, significantly smaller than that for the majority of bulge stars (50–60 km s−1 kpc−1); bulge RRLs have larger velocity dispersion (120–140 km s−1) than younger stars. The dependence of the kinematics of the bulge RRLs on their metallicities is shown by their rotation curves and spatial distributions. Metal-poor RRLs ([Fe/H]<−1) show a smaller bar angle than metal-rich ones. We also find clues suggesting that RRLs in the bulge are not dominated by halo stars. These results might explain some previous conflicting results over bulge RRLs and help understand the chemodynamical evolution of the Galactic bulge.
Revisiting the spectral and timing properties of 4U 1909+07 with NuSTAR and Astrosat
Authors: Jaisawal Gaurava K , Naik Sachindra , Ho Wynn C G , Kumari Neeraj , Epili Prahlad , Vasilopoulos Georgios
Published: August 2020

We present the results obtained from the analysis of high-mass X-ray binary pulsar 4U 1909+07 using NuSTAR and Astrosat observations in July 2015 and 2017, respectively. X-ray pulsations at ≈604 s are clearly detected in our study. Based on the long-term spin-frequency evolution, the source is found to spun-up in the last 17 yr. We observed a strongly energy-dependent pulse profile that evolved from a complex broad structure in soft X-rays into a profile with a narrow emission peak followed by a plateau in energy ranges above 20 keV. This behaviour ensured a positive correlation between the energy and pulse fraction. The pulse profile morphology and its energy evolution are almost similar during both the observations, suggesting a persistent emission geometry of the pulsar over time. The broad-band energy spectrum of the pulsar is approximated by an absorbed high-energy exponential cut-off power-law model with iron emission lines. In contrast to the previous report, we found no statistical evidence for the presence of cyclotron absorption features in the X-ray spectra. We performed phase-resolved spectroscopy using data from the NuSTAR observation. Our results showed a clear signature of absorbing material at certain pulse phases of the pulsar. These findings are discussed in terms of stellar wind distribution and its effect on the beam geometry of this wind-fed accreting neutron star. We also reviewed the subsonic quasi-spherical accretion theory and its implication on the magnetic field of 4U 1909+07 depending on the global spin-up rate.
Tidally induced warps of spiral galaxies in IllustrisTNG
Authors: Semczuk Marcin , Łokas Ewa L , D’Onghia Elena , Athanassoula E , Debattista Victor P , Hernquist Lars
Published: August 2020

Warps are common features in both stellar and gaseous discs of nearby spiral galaxies with the latter usually easier to detect. Several theories have been proposed in the literature to explain their formation and prevalence, including tidal interactions with external galaxies. Observational correlations also suggest the importance of tides for warp formation. Here, we use the TNG100 run from the magnetohydrodynamical cosmological simulation suite IllustrisTNG to investigate the connection between interactions and the formation of gas warps. We find that in the sample of well-resolved gas-rich spiral galaxies (1010 ≲ M*/M⊙ ≲ 1011 at z = 0) from the simulation TNG100-1, about 16 per cent possess the characteristic S-shaped warp. Around one-third of these objects have their warps induced by interactions with other galaxies. Half of these interactions end with the perturber absorbed by the host by z = 0. We find that warps induced by interactions survive on average for <1 Gyr, similarly to the remaining S-shaped warps. The angle between the orbital angular momentum of the perturber and the angular momentum of the host’s disc that most likely leads to warp formation is around 45°. While our main goal is to investigate tidally induced warps, we find that during interactions in addition to tides, new gas that is accreted from infalling satellites also can contribute to warp formation.
Impact of the reflection model on the estimate of the properties of accreting black holes
Authors: Tripathi Ashutosh , Liu Honghui , Bambi Cosimo
Published: August 2020

Relativistic reflection features in the X-ray spectra of black hole binaries and active galactic nuclei originate from illumination of the inner part of the accretion disc by a hot corona. In the presence of high quality data and with the correct astrophysical model, X-ray reflection spectroscopy can be quite a powerful tool to probe the strong gravity region, study the morphology of the accreting matter, measure black hole spins, and even test Einstein’s theory of general relativity in the strong field regime. There are a few relativistic reflection models available today and developed by different groups. All these models present some differences and have a number of simplifications introducing systematic uncertainties. The question is whether different models provide different measurements of the properties of black holes and how to arrive at a common model for the whole X-ray astronomy community. In this paper, we start exploring this issue by analysing a Suzaku observation of the stellar-mass black hole in GRS 1915+105 and simultaneous XMM–Newton and NuSTAR observations of the supermassive black hole in MCG-6-30-15. The relativistic reflection component of these sources is fitted with relconv × reflionx, relconv × xillver, and relxill. We discuss the differences and the impact on the study of accreting black holes.