bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protein expression profiles in methicillin-resistant Staphylococcus aureus (MRSA) under effects of subminimal inhibitory concentrations of imipenem
Authors: Wang Jichun , Wang Junrui , Wang Yanyan , Sun Peng , Zou Xiaohui , Ren Luo , Zhang Chunxia , Liu Enmei 
Published: September 2019

ABSTRACT
Imipenem is a beta-lactam antibiotic mainly active against gram-negative bacterial pathogens and also could cause cell wall impairment in methicillin-resistant Staphylococcus aureus(MRSA). However, related antibacterial mechanisms of imipenem on MRSA and mixed infections of MRSA and gram-negative bacteria are relatively poorly revealed. This study was to identify proteins in the MRSA response to subminimal inhibitory concentrations (sub-MICs) of imipenem treatment. Our results showed that 240 and 58 different expression proteins (DEPs) in sub-MICs imipenem-treated S3 (a standard MRSA strain) and S23 (a clinical MRSA strain) strains were identified through the isobaric tag for relative and absolute quantitation method when compared with untreated S3 and S23 strains, respectively, which was further confirmed by multiple reactions monitoring. Our result also demonstrated that expressions of multiple DEPs involved in cellular proliferation, metabolism and virulence were significantly changed in S3 and S23 strains, which was proved by gene ontology annotations and qPCR analysis. Further, transmission electron microscopy and scanning electron microscopy analysis showed cell wall deficiency, cell lysis and abnormal nuclear mitosis on S23 strain. Our study provides important information for understanding the antibacterial mechanisms of imipenem on MRSA and for better usage of imipenem on patients co-infected with MRSA and other multidrug-resistant gram-negative bacteria.
Identification and characterization of FtsH mediating in vivo colonization and stress adaptation in the fish pathogen Edwardsiella piscicida
Authors: Ma Ruiqing , Huang Jianchang , Zhang Yuanxing , Wang Qiyao 
Published: September 2019

ABSTRACT
Edwardsiella piscicida is an important pathogenic enteric bacterium of fish. FtsH is a unique membrane-anchored AAA + protease that regulates protein homeostasis in bacteria. In cooperation with modulators HflK and HflC, FtsH is essential in enteric bacteria and controls the response to environmental stresses. Here, we used in vivo pattern analysis of conditional essentiality (PACE) and identified that ftsH and hflK/C were associated with impaired in vivo colonization in Edw. piscicida and attenuated internalization ability of ZF4 cells. The ftsH mutant displayed increased survival during prolonged treatment of starvation and high osmotic stresses in Edw. piscicida. Further analysis showed that the disruption of ftsH resulted in the overproduction of the established substrate LpxC, which is responsible for the synthesis of LPS (lipopolysaccharide), as well as the substrate YfgM, which is involved in high osmolality tolerance during stationary phase. However, the inconsistency in the abilities of the ftsH and hflK/C mutants to achieve YfgM-based osmotic resistance indicated that there might be multiple, while distinctive, pathways controlled by FtsH and the associated modulator proteins HflK/C. This investigation revealed the unique functions of FtsH and its modulator HflK/C in Edw. piscicida.
Land seismic multiparameter full waveform inversion in elastic VTI media by simultaneously interpreting body waves and surface waves with an optimal transport based objective function
Authors: He Weiguang , Brossier Romain , Métivier Ludovic , Plessix René-Édouard 
Published: September 2019

SUMMARY
Land seismic multiparameter full waveform inversion in anisotropic media is challenging because of high medium contrasts and surface waves. With a data-residual least-squares objective function, the surface wave energy usually masks the body waves and the gradient of the objective function exhibits high values in the very shallow depths preventing from recovering the deeper part of the earth model parameters. The optimal transport objective function, coupled with a Gaussian time-windowing strategy, allows to overcome this issue by more focusing on phase shifts and by balancing the contributions of the different events in the adjoint-source and the gradients. We first illustrate the advantages of the optimal transport function with respect to the least-squares one, with two realistic examples. We then discuss a vertical transverse isotropic (VTI) example starting from a quasi 1-D isotropic initial model. Despite some cycle-skipping issues in the initial model, the inversion based on the windowed optimal transport approach converges. Both the near-surface complexities and the variations at depth are recovered.
Exploiting the emergent nature of mixed methods designs: insights from a mixed methods impact evaluation in Malawi
Authors: De Allegri Manuela , Brenner Stephan , Kambala Christabel , Mazalale Jacob , Muula Adamson S , Chinkhumba Jobiba , Wilhelm Danielle , Lohmann Julia 
Published: September 2019

Abstract
The application of mixed methods in Health Policy and Systems Research (HPSR) has expanded remarkably. Nevertheless, a recent review has highlighted how many mixed methods studies do not conceptualize the quantitative and the qualitative component as part of a single research effort, failing to make use of integrated approaches to data collection and analysis. More specifically, current mixed methods studies rarely rely on emergent designs as a specific feature of this methodological approach. In our work, we postulate that explicitly acknowledging the emergent nature of mixed methods research by building on a continuous exchange between quantitative and qualitative strains of data collection and analysis leads to a richer and more informative application in the field of HPSR. We illustrate our point by reflecting on our own experience conducting the mixed methods impact evaluation of a complex health system intervention in Malawi, the Results Based Financing for Maternal and Newborn Health Initiative. We describe how in the light of a contradiction between the initial set of quantitative and qualitative findings, we modified our design multiple times to include additional sources of quantitative and qualitative data and analytical approaches. To find an answer to the initial riddle, we made use of household survey data, routine health facility data, and multiple rounds of interviews with both healthcare workers and service users. We highlight what contextual factors made it possible for us to maintain the high level of methodological flexibility that ultimately allowed us to solve the riddle. This process of constant reiteration between quantitative and qualitative data allowed us to provide policymakers with a more credible and comprehensive picture of what dynamics the intervention had triggered and with what effects, in a way that we would have never been able to do had we kept faithful to our original mixed methods design.
Concrete Examples of Abstract Others: Testing Exemplar Availability as an Additional Explanation for Third-Person Perceptions
Authors: Schmierbach Mike , Boyle Michael P 
Published: September 2019

Abstract
Explanations for the third-person phenomenon generally hinge on either self-favoring biases or cognitive mechanisms. While controlling for common perceptual factors, we demonstrate an additional cognitive component: exemplar availability, using a 2-study design. The first considers the third-person perception in the context of media-generated stereotypes. The second considers 3 distinct types of advertisements meant to evoke varied third- and first-person perceptions. Results of both studies showed that the ability to think of examples serves as the most consistent predictor, even after accounting for the influence of perceived exposure and similarity.
Cefepime/sulbactam as an enhanced antimicrobial combination therapy for the treatment of MDR Gram-negative infections
Authors: Wareham David W , Momin M H F Abdul , Phee Lynette M , Hornsey Michael , Standing Joseph F 
Published: September 2019

Abstract

Background
β-Lactam (BL)/β-lactamase inhibitor (BLI) combinations are widely used for the treatment of Gram-negative infections. Cefepime has not been widely studied in combination with BLIs. Sulbactam, with dual BL/BLI activity, has been partnered with very few BLs. We investigated the potential of cefepime/sulbactam as an unorthodox BL/BLI combination against MDR Gram-negative bacteria.

Methods
In vitro activity of cefepime/sulbactam (1:1, 1:2 and 2:1) was assessed against 157 strains. Monte Carlo simulation was used to predict the PTA with a number of simulated cefepime combination regimens, modelled across putative cefepime/sulbactam breakpoints (≤16/≤0.25 mg/L).

Results
Cefepime/sulbactam was more active (MIC50/MIC90 8/8–64/128 mg/L) compared with either drug alone (MIC50/MIC90 128 to >256 mg/L). Activity was enhanced when sulbactam was added at 1:1 or 1:2 (P < 0.05). Reduction in MIC was most notable against Acinetobacter baumannii and Enterobacterales (MIC 8/8–32/64 mg/L). Pharmacokinetic/pharmacodynamic modelling highlighted that up to 48% of all isolates and 73% of carbapenem-resistant A. baumannii with a cefepime/sulbactam MIC of ≤16/≤8 mg/L may be treatable with a high-dose, fixed-ratio (1:1 or 1:2) combination of cefepime/sulbactam.

Conclusions
Cefepime/sulbactam (1:1 or 1:2) displays enhanced in vitro activity versus MDR Gram-negative pathogens. It could be a potential alternative to existing BL/BLI combinations for isolates with a cefepime/sulbactam MIC of 16/8 mg/L either as a definitive treatment or as a carbapenem-sparing option.
Antimicrobial anaphylaxis: the changing face of severe antimicrobial allergy
Authors: Hall Victoria , Wong Micah , Munsif Maitri , Stevenson Brittany R , Elliott Katie , Lucas Michaela , Baird Ashleigh J , Athan Eugene , Young Melissa , Pickles Robert , Cheng Allen C , Stewardson Andrew J , Aung Ar K , Trubiano Jason A 
Published: September 2019

Abstract

Objectives
The epidemiology, clinical characteristics and outcomes of antimicrobial-associated anaphylaxis remain ill-defined. We sought to examine antimicrobial anaphylaxis with regard to: (i) the frequency of implicated antimicrobials; (ii) attributable mortality; and (iii) referral for definitive allergy assessment.

Methods
This was conducted through a national retrospective multicentre cohort study at five Australian tertiary hospitals (January 2010 to December 2015). Cases of antimicrobial anaphylaxis were identified from ICD-10 coding and adverse drug reaction committee databases.

Results
There were 293 participants meeting the case definition of antimicrobial anaphylaxis and 310 antimicrobial anaphylaxis episodes. Of 336 implicated antimicrobials, aminopenicillins (62/336, 18.5%) and aminocephalosporins (57/336, 17%) were implicated most frequently. ICU admission occurred in 43/310 (13.9%) episodes; however, attributable mortality was low (3/310, 1%). The rate of anaphylaxis to IV antibiotics was 3.5 (95% CI = 2.9–4.3) per 100 000 DDDs and the rate of hospital-acquired anaphylaxis was 1.9 (95% CI = 2.1–3.3) per 100 000 occupied bed-days. We observed overall low rates of hospital discharge documentation (222/310, 71.6%) and follow-up by specialist allergy services (73/310, 23.5%), which may compromise medication safety and antimicrobial prescribing in future.

Conclusions
This study demonstrated that a high proportion of severe immediate hypersensitivity reactions presenting or acquired in Australian hospitals are secondary to aminopenicillins and aminocephalosporins. Overall rates of hospital-acquired anaphylaxis, predominantly secondary to cephalosporins, are low, and also associated with low inpatient mortality.
Tests of acoustic scale shifts in halo-based mock galaxy catalogues
Authors: Duan Yutong , Eisenstein Daniel 
Published: September 2019

ABSTRACT
We utilize mock catalogues from high-accuracy cosmological N-body simulations to quantify shifts in the recovery of the acoustic scale that could potentially result from galaxy clustering bias. The relationship between galaxies and dark matter haloes presents a complicated source of systematic errors in modern redshift surveys, particularly when aiming to make cosmological measurements to sub-per cent precision. Apart from a scalar, linear bias parameter accounting for the density contrast ratio between matter tracers and the true matter distribution, other types of galaxy bias, such as assembly and velocity biases, may also significantly alter clustering signals from small to large scales. We create mocks based on generalized halo occupation populations of 36 periodic boxes from the abacus cosmosrelease, and test various biased models along with an unbiased base case in a total volume of $48 \, h^{-3} \, {\rm Gpc}^{3}$. Two reconstruction methods are applied to galaxy samples and the apparent acoustic scale is derived by fitting the two-point correlation function multipoles. With respect to the baseline, we find a 0.3 per cent shift in the line-of-sight acoustic scale for one variation in the satellite galaxy population, and we find a 0.7 per cent shift for an extreme level of velocity bias of the central galaxies. All other bias models are consistent with zero shift at the 0.2 per cent level after reconstruction. We note that the bias models explored are relatively large variations, producing sizeable and likely distinguishable changes in small-scale clustering, the modelling of which would further calibrate the baryon acoustic oscillations standard ruler.
Dynamical interactions in the planetary system GJ4276
Authors: Horrobin Fergus , Rein Hanno 
Published: September 2019

ABSTRACT
GJ4276 is an M4.0 dwarf star with an inferred Neptune mass planet from radial velocity (RV) observations. We re-analyse the RV data for this system and focus on the possibility of a second, super-Earth mass, planet. We compute the time-scale for fast resonant librations in the eccentricity to be $\sim \!2000 \, \mathrm{d}$. Given that the observations were taken over $700\, \mathrm{d}$, we expect to see the effect of these librations in the observations. We perform a fully dynamical fit to test this hypothesis. Similar to previous results, we determine that the data could be fit by two planets in a 2:1 mean motion resonance. However, we also find solutions near the 5:4 mean motion resonance that are not present when planet–planet interactions are ignored. Using the mean exponential growth of nearby orbits indicator, we analyse the stability of the system and find that our solutions lie in a stable region of parameter space. We also find that though out-of-resonance solutions are possible, the system favours a configuration that is in a first-order mean motion resonance. The existence of mean motion resonances has important implications in many planet formation theories. Although we do not attempt to distinguish between the one- and two-planet models in this work, in either case, the predicted orbital parameters are interesting enough to merit further study. Future observations should be able to distinguish between the different scenarios within the next 5 yr.
Optical transient from an explosion close to the stellar surface
Authors: Yalinewich Almog , Matzner Christopher D 
Published: September 2019

ABSTRACT
We study the hydrodynamic evolution of an explosion close to the stellar surface, and give predictions for the radiation from such an event. We show that such an event will give rise to a multiwavelength transient. We apply this model to describe a precursor burst to the peculiar supernova iPTF14hls, which occurred in 1954, 60 yr before the supernova. We propose that the new generation of optical surveys might detect similar transients, and that they can be used to identify supernova progenitors well before the explosion.
Multifilter time-series observations of three short period ATLAS variable stars
Authors: Koen Chris 
Published: September 2019

ABSTRACT
The ‘Asteroid Terrestrial-impact Last Alert System’ discovered hundreds of thousands of new candidate variable stars. Follow-up observations of three of these are reported in this paper. The targets were selected on the basis of having high probability of being periodic (false alarm probability for period detection smaller than 10−5), short periods (P < 0.2 d), and being relatively bright (g′ < 17). The targets were also chosen to be either very blue (g′ − i′ < −0.4, r′ − z′ < −0.4) or very red (g′ − i′ > 2.2, r′ − z′ > 1.5) as periodic variables with these colours are relatively rare. Two of the stars are hot subdwarfs, both of which are likely reflection effect binaries. In both cases simple models suggest that the companions may have masses very close to or below 0.1 $\, \mathrm{M}_\odot$. The third star is also a binary, which appears to consist of two M dwarfs in a near contact configuration. At 0.12 d its period is one of the shortest known for M-type binaries.
An interpretable machine-learning framework for dark matter halo formation
Authors: Lucie-Smith Luisa , Peiris Hiranya V , Pontzen Andrew 
Published: September 2019

ABSTRACT
We present a generalization of our recently proposed machine-learning framework, aiming to provide new physical insights into dark matter halo formation. We investigate the impact of the initial density and tidal shear fields on the formation of haloes over the mass range 11.4 ≤ log (M/M⊙) ≤ 13.4. The algorithm is trained on an N-body simulation to infer the final mass of the halo to which each dark matter particle will later belong. We then quantify the difference in the predictive accuracy between machine-learning models using a metric based on the Kullback–Leibler divergence. We first train the algorithm with information about the density contrast in the particles’ local environment. The addition of tidal shear information does not yield an improved halo collapse model over one based on density information alone; the difference in their predictive performance is consistent with the statistical uncertainty of the density-only based model. This result is confirmed as we verify the ability of the initial conditions-to-halo mass mapping learnt from one simulation to generalize to independent simulations. Our work illustrates the broader potential of developing interpretable machine-learning frameworks to gain physical understanding of non-linear large-scale structure formation.
Controlling systematics in ground-based CMB surveys with partial boresight rotation
Authors: Thomas Daniel B , McCallum Nialh , Brown Michael L 
Published: September 2019

ABSTRACT
Future CMB experiments will require exquisite control of systematics in order to constrain the B-mode polarization power spectrum. One class of systematics that requires careful study is instrumental systematics. The potential impact of such systematics is most readily understood by considering analysis pipelines based on pair differencing. In this case, any differential gain, pointing or beam ellipticity between the two detectors in a pair can result in intensity leakage into the B-mode spectrum, which needs to be controlled to a high precision due to the much greater magnitude of the total intensity signal as compared to the B-mode signal. One well-known way to suppress such systematics is through careful design of the scan-strategy, in particular making use of any capability to rotate the instrument about its pointing (boresight) direction. Here, we show that the combination of specific choices of such partial boresight rotation angles with redundancies present in the scan strategy is a powerful approach for suppressing systematic effects. This mitigation can be performed in analysis in advance of map-making and, in contrast to other approaches (e.g. deprojection or filtering), results in no signal loss. We demonstrate our approach explicitly with time ordered data simulations relevant to next-generation ground-based CMB experiments, using deep and wide scan strategies appropriate for experiments based in Chile. These simulations show a reduction of multiple orders of magnitude in the spurious B-mode signal arising from differential gain and differential pointing systematics.
Search for RR Lyrae stars in DES ultrafaint systems: Grus I, Kim 2, Phoenix II, and Grus II
Authors: Martínez-Vázquez C E , Vivas A K , Gurevich M , Walker A R , McCarthy M , Pace A B , Stringer K M , Santiago B , Hounsell R , Macri L , Li T S , Bechtol K , Riley A H , Kim A G , Simon J D , Drlica-Wagner A , Nadler E O , Marshall J L , Annis J , Avila S , Bertin E , Brooks D , Buckley-Geer E , Burke D L , Carnero Rosell A , Carrasco Kind M , da Costa L N , De Vicente J , Desai S , Diehl H T , Doel P , Everett S , Frieman J , García-Bellido J , Gaztanaga E , Gruen D , Gruendl R A , Gschwend J , Gutierrez G , Hollowood D L , Honscheid K , James D J , Kuehn K , Kuropatkin N , Maia M A G , Menanteau F , Miller C J , Miquel R , Paz-Chinchón F , Plazas A A , Sanchez E , Scarpine V , Serrano S , Sevilla-Noarbe I , Smith M , Soares-Santos M , Sobreira F , Swanson M E C , Tarle G , Vikram V ,   (DES Collaboration)
Published: September 2019

ABSTRACT
This work presents the first search for RR Lyrae stars (RRLs) in four of the ultrafaint systems imaged by the Dark Energy Survey using SOAR/Goodman and Blanco/DECam imagers. We have detected two RRLs in the field of Grus I, none in Kim 2, one in Phoenix II, and four in Grus II. With the detection of these stars, we accurately determine the distance moduli for these ultrafaint dwarf satellite galaxies; μ0 = 20.51 ± 0.10 mag (D⊙ = 127 ± 6 kpc) for Grus I and μ0 = 20.01 ± 0.10 mag (D⊙ = 100 ± 5 kpc) for Phoenix II. These measurements are larger than previous estimations by Koposov et al. and Bechtol et al., implying larger physical sizes; 5 per cent for Grus I and 33 per cent for Phoenix II. For Grus II, of the four RRLs detected, one is consistent with being a member of the galactic halo (D⊙ = 24 ± 1 kpc, μ0 = 16.86 ± 0.10 mag), another is at D⊙ = 55 ± 2 kpc (μ0 = 18.71 ± 0.10 mag), which we associate with Grus II, and the two remaining at D⊙ = 43 ± 2 kpc (μ0 = 18.17 ± 0.10 mag). Moreover, the appearance of a subtle red horizontal branch in the colour–magnitude diagram of Grus II at the same brightness level of the latter two RRLs, which are at the same distance and in the same region, suggests that a more metal-rich system may be located in front of Grus II. The most plausible scenario is the association of these stars with the Chenab/Orphan Stream. Finally, we performed a comprehensive and updated analysis of the number of RRLs in dwarf galaxies. This allows us to predict that the method of finding new ultrafaint dwarf galaxies using two or more clumped RRLs will work only for systems brighter than MV ∼ −6 mag.
A nitrogen-enhanced metal-poor star discovered in the globular cluster ESO280−SC06
Authors: Simpson Jeffrey D , Martell Sarah L 
Published: September 2019

ABSTRACT
We report the discovery of the only very nitrogen-enhanced metal-poor star known in a Galactic globular cluster. This star, in the very metal-poor cluster ESO280−SC06 , has $[\textrm{N}/\textrm{Fe}]\, \gt +2.5$, while the other stars in the cluster show no obvious enhancement in nitrogen. Around 80 NEMP stars are known in the field, and their abundance patterns are believed to reflect mass transfer from a binary companion in the asymptotic giant branch phase. The dense environment of globular clusters is detrimental to the long term survival of binary systems, resulting in a low observed binary fraction among red giants and the near absence of NEMP stars. We also identify the first known horizontal branch members of ESO280−SC06 , which allow for a much better constraint on its distance. We calculate an updated orbit for the cluster based on our revised distance of 20.6 ± 0.5 kpc, and find no significant change to its orbital properties.