bluuebunny/crossref_metadata_2025 huggingface dataset:
GEOMAX: beyond linear compression for three-point galaxy clustering statistics
Authors: Gualdi Davide , Gil-Marín Héctor , Manera Marc , Joachimi Benjamin , Lahav Ofer
Published: July 2020

We present the GEOMAX algorithm and its python implementation for a two-step compression of bispectrum measurements. The first step groups bispectra by the geometric properties of their arguments; the second step then maximizes the Fisher information with respect to a chosen set of model parameters in each group. The algorithm only requires the derivatives of the data vector with respect to the parameters and a small number of mock data, producing an effective, non-linear compression. By applying GEOMAX to bispectrum monopole measurements from BOSS DR12 CMASS redshift-space galaxy clustering data, we reduce the 68 per cent credible intervals for the inferred parameters (b1, b2, f, σ8) by 50.4, 56.1, 33.2, and 38.3 per cent with respect to standard MCMC on the full data vector. We run the analysis and comparison between compression methods over 100 galaxy mocks to test the statistical significance of the improvements. On average, GEOMAX performs ∼15 per cent better than geometrical or maximal linear compression alone and is consistent with being lossless. Given its flexibility, the GEOMAX approach has the potential to optimally exploit three-point statistics of various cosmological probes like weak lensing or line-intensity maps from current and future cosmological data sets such as DESI, Euclid, PFS, and SKA.
A non-linear mathematical model for the X-ray variability of the microquasar GRS 1915+105 – III. Low-frequency quasi-periodic oscillations
Authors: Massaro E , Capitanio F , Feroci M , Mineo T
Published: July 2020

The X-ray emission from the microquasar GRS 1915+105 shows, together with a very complex variability on different time-scales, the presence of low-frequency quasi-periodic oscillations (LFQPOs) at frequencies lower than ∼30 Hz. In this paper, we demonstrate that these oscillations can be consistently and naturally obtained as solutions of a system of two ordinary differential equations, which is able to reproduce almost all variability classes of GRS 1915+105. We modified the Hindmarsh–Rose model and obtained a system with two dynamical variables x(t), y(t), where the first one represents the X-ray flux from the source, and an input function J(t), whose mean level J0 and its time evolution is responsible of the variability class. We found that for values of J0 around the boundary between the unstable and the stable interval, where the equilibrium points are of spiral type, one obtains an oscillating behaviour in the model light curve similar to the observed ones with a broad Lorentzian feature in the power density spectrum and, occasionally, with one or two harmonics. Rapid fluctuations of J(t), as those originating from turbulence, stabilize the LFQPOs, resulting in a slowly amplitude modulated pattern. To validate the model, we compared the results with real RXTE data, which resulted remarkably similar to those obtained from the mathematical model. Our results allow us to favour an intrinsic hypothesis on the origin of LFQPOs in accretion discs ultimately related to the same mechanism responsible for the spiking limit cycle.
Analysis of Phobos’ dynamical environment considering effects of ephemerides and physical libration
Authors: Wang Yue , Wu Xiaojie
Published: July 2020

A dynamical model is developed in the body-fixed frame of Phobos, in which the high-precision gravity field and exact physical libration of Phobos, the gravity of Mars with J2, and the gravity perturbations of the Sun, Jupiter, and Earth are considered. The JPL development ephemeris are applied to calculate the positions of celestial bodies. Phobos is considered as a homogeneous polyhedron with 16 037 vertices to characterize its irregular shape and the corresponding gravity field. The physical libration of Phobos is incorporated into its rotational motion by using the results in ‘Report of the IAU WGCCRE’. With the proposed model, equivalent gravity and slope on Phobos surface are calculated and analysed. The liftoff velocity is also computed and presented. Besides, the orbital environment is also investigated. Instantaneous equilibrium points in the Mars–Phobos system are computed and demonstrated, and the acceleration of a particle in the vicinity of Phobos is analysed to find out the main influencing factor in different regions. Quasi-satellite orbits and libration point orbits, which were determined in the circular restricted three-body problem model, are simulated in different dynamical models. The results applying the newly developed high-fidelity dynamical model have shown significant differences with respect to existing models, suggesting that dynamical models with higher accuracy are needed for close-range orbital activities.
Probing the high-z IGM with the hyperfine transition of 3He+
Authors: Khullar Shivan , Ma Qingbo , Busch Philipp , Ciardi Benedetta , Eide Marius B , Kakiichi Koki
Published: July 2020

The hyperfine transition of 3He+ at 3.5 cm has been thought as a probe of the high-z IGM, since it offers a unique insight into the evolution of the helium component of the gas, as well as potentially give an independent constraint on the 21 cm signal from neutral hydrogen. In this paper, we use radiative transfer simulations of reionization driven by sources such as stars, X-ray binaries, accreting black holes and shock heated interstellar medium, and simulations of a high-z quasar to characterize the signal and analyse its prospects of detection. We find that the peak of the signal lies in the range ∼1–50 μK for both environments, but while around the quasar it is always in emission, in the case of cosmic reionization a brief period of absorption is expected. As the evolution of He ii is determined by stars, we find that it is not possible to distinguish reionization histories driven by more energetic sources. On the other hand, while a bright QSO produces a signal in 21 cm that is very similar to the one from a large collection of galaxies, its signature in 3.5 cm is very peculiar and could be a powerful probe to identify the presence of the QSO. We analyse the prospects of the signal’s detectability using SKA1-mid as our reference telescope. We find that the noise power spectrum dominates over the power spectrum of the signal, although a modest signal-to-noise ratio can be obtained when the wavenumber bin width and the survey volume are sufficiently large.
VALES VI: ISM enrichment in star-forming galaxies up to z ∼ 0.2 using 12CO(1–0), 13CO(1–0), and C18O(1–0) line luminosity ratios
Authors: Méndez-Hernández H , Ibar E , Knudsen K K , Cassata P , Aravena M , Michałowski M J , Zhang Zhi-Yu , Lara-López M A , Ivison R J , van der Werf P , Villanueva V , Herrera-Camus R , Hughes T M
Published: July 2020

We present Atacama Large Millimeter/sub-millimeter Array (ALMA) observations towards 27 low-redshift (0.02 < z < 0.2) star-forming galaxies taken from the Valparaíso ALMA/APEX Line Emission Survey. We perform stacking analyses of the 12CO(1–0), 13CO(1–0), and C18O(1–0) emission lines to explore the L′ [12CO(1–0)]/L′ [13CO(1–0)] [hereafter L′ (12CO)/L′ (13CO)] and L′ [13CO(1–0)]/L′ [C18O(1–0)] [hereafter L′ (13CO)/L′ (C18O)] line luminosity ratio dependence as a function of different global galaxy parameters related to the star formation activity. The sample has far-IR luminosities of $10^{10.1\!-\!11.9}\,$ L⊙ and stellar masses of 109.8–10.9 M⊙ corresponding to typical star-forming and starburst galaxies at these redshifts. On average, we find an L′ (12CO)/L′ (13CO) line luminosity ratio value of 16.1 ± 2.5. Galaxies with pieces of evidence of possible merging activity tend to show higher L′ (12CO)/L′ (13CO) ratios by a factor of 2, while variations of this order are also found in galaxy samples with higher star formation rates (SFRs) or star formation efficiencies (SFEs). We also find an average L′ (13CO)/L′ (C18O) line luminosity ratio of 2.5 ± 0.6, which is in good agreement with those previously reported for starburst galaxies. We find that galaxy samples with high LIR, SFR, and SFE show low L′ (13CO)/L′ (C18O) line luminosity ratios with high L′ (12CO)/L′ (13CO) line luminosity ratios, suggesting that these trends are produced by selective enrichment of massive stars in young starbursts.
MeerKAT-16 H i observation of the dIrr galaxy WLM
Authors: Ianjamasimanana Roger , Namumba Brenda , Ramaila Athanaseus J T , Saburova Anna S , Józsa Gyula I G , Myburgh Talon , Thorat Kshitij , Carignan Claude , Maina Eric , de Blok W J G , Andati Lexy A L , Hugo Benjamin V , Kleiner Dane , Kamphuis Peter , Serra Paolo , Smirnov Oleg M , Maccagni Filippo M , Makhathini Sphesihle , Molnár Dániel Cs , Perkins Simon , Ramatsoku Mpati , White Sarah V
Published: July 2020

We present observations and models of the kinematics and the distribution of the neutral hydrogen (H i) in the isolated dwarf irregular galaxy, Wolf-Lundmark-Melotte (WLM). We observed WLM with the Green Bank Telescope (GBT) and as part of the MeerKAT Early Science Programme, where 16 dishes were available. The H i disc of WLM extends out to a major axis diameter of 30 arcmin (8.5 kpc), and a minor axis diameter of 20 arcmin (5.6 kpc) as measured by the GBT. We use the MeerKAT data to model WLM using the tirific software suite, allowing us to fit different tilted-ring models and select the one that best matches the observation. Our final best-fitting model is a flat disc with a vertical thickness, a constant inclination and dispersion, and a radially varying surface brightness with harmonic distortions. To simulate bar-like motions, we include second-order harmonic distortions in velocity in the tangential and vertical directions. We present a model with only circular motions included and a model with non-circular motions. The latter describes the data better. Overall, the models reproduce the global distribution and the kinematics of the gas, except for some faint emission at the 2σ level. We model the mass distribution of WLM with pseudo-isothermal (ISO) and Navarro–Frenk–White (NFW) dark matter halo models. The NFW and the ISO models fit the derived rotation curves within the formal errors, but with the ISO model giving better reduced chi-square values. The mass distribution in WLM is dominated by dark matter at all radii.
On the cosmological performance of photometrically classified supernovae with machine learning
Authors: Santos Marcelo Vargas dos , Quartin Miguel , Reis Ribamar R R
Published: July 2020

The efficient classification of different types of supernovae is one of the most important problems for observational cosmology. However, spectroscopic confirmation of most objects in upcoming photometric surveys, such as the the Rubin Observatory Legacy Survey of Space and Time, will be unfeasible. The development of automated classification processes based on photometry has thus become crucial. In this paper, we investigate the performance of machine learning (ML) classification on the final cosmological constraints using simulated light-curves from the Supernova Photometric Classification Challenge, released in 2010. We study the use of different feature sets for the light-curves and many different ML pipelines based on either decision-tree ensembles or automated search processes. To construct the final catalogues we propose a threshold selection method, by employing a bias-variance tradeoff. This is a very robust and efficient way to minimize the mean squared error. With this method, we were able to obtain very strong cosmological constraints, which allowed us to keep $\sim 75{{\ \rm per\ cent}}$ of the total information in the Type Ia supernovae when using the SALT2 feature set, and $\sim 33{{\ \rm per\ cent}}$ for the other cases (based either on the Newling model or on standard wavelet decomposition).
The κ-cookbook: a novel generalizing approach to unify κ-like distributions for plasma particle modelling
Authors: Scherer K , Husidic E , Lazar M , Fichtner H
Published: July 2020

In the literature different so-called κ-distribution functions are discussed to fit and model the velocity (or energy) distributions of solar wind species, pickup ions, or magnetospheric particles. Here, we introduce a generalized (isotropic) κ-distribution as a ‘cookbook’, which admits as special cases, or ‘recipes’, all the other known versions of κ-models. A detailed analysis of the generalized distribution function is performed, providing general analytical expressions for the velocity moments, Debye length, and entropy, and pointing out a series of general requirements that plasma distribution functions should satisfy. From a contrasting analysis of the recipes found in the literature, we show that all of them lead to almost the same macroscopic parameters with a small standard deviation between them. However, one of these recipes called the regularized κ-distribution provides a functional alternative for macroscopic parametrization without any constraint for the power-law exponent κ.
NGTS clusters survey – II. White-light flares from the youngest stars in Orion
Authors: Jackman James A G , Wheatley Peter J , Acton Jack S , Anderson David R , Belardi Claudia , Burleigh Matthew R , Casewell Sarah L , Eigmüller Philipp , Gill Samuel , Gillen Edward , Goad Michael R , Grange Andrew , Hodgkin Simon T , Jenkins James S , McCormac James , Moyano Maximiliano , Queloz Didier , Raynard Liam , Tilbrook Rosanna H , Watson Christopher A , West Richard G
Published: July 2020

We present the detection of high-energy white-light flares from pre-main-sequence stars associated with the Orion Complex, observed as part of the Next Generation Transit Survey (NGTS). With energies up to 5.2 × 1035 erg these flares are some of the most energetic white-light flare events seen to date. We have used the NGTS observations of flaring and non-flaring stars to measure the average flare occurrence rate for 4 Myr M0–M3 stars. We have also combined our results with those from previous studies to predict average rates for flares above 1 × 1035 erg for early M stars in nearby young associations.
Periodic fast radio bursts from forcedly precessing neutron stars, anomalous torque, and internal magnetic field for FRB 180916.J0158+65 and FRB 121102
Authors: Sob’yanin (Денис Николаевич Собьянин) Denis Nikolaevich
Published: July 2020

A recent discovery of the periodic activity of the repeating fast radio burst source FRB 180916.J0158+65 in the Canadian Hydrogen Intensity Mapping Experiment (CHIME) hints at possible origin of the FRB from a freely precessing neutron star with a magnetar magnetic field of about 1016 G. However, the absence of simultaneously detected high-energy emission in the Swift and AGILE observations imposes stringent constraints on the field magnitude and questions the possibility of such a progenitor. We show that consideration of forced precession of a neutron star does not encounter the difficulty. This kind of precession takes place even if the neutron star is not deformed and is brought about by the anomalous moment of electromagnetic forces induced by stellar rotation and determined by non-corotational currents. Contrary to what is expected for the currents of corotation, the anomalous torque calculated by the direct method appears to be non-zero. If the observed 16.35-d period corresponds to the period of stellar precession, the inferred internal magnetic field appears to be about 6 × 1014 G for rotational period 1 s. For another possibly periodic FRB 121102 with 157-d period, the magnetic field is even lower, 2 × 1014 G, thereby justifying earlier considerations and not ruling out the hypothesis of FRB origin from precessing neutron stars.
The chemical structure and phosphorothioate content of hydrophobically modified siRNAs impact extrahepatic distribution and efficacy
Authors: Biscans Annabelle , Caiazzi Jillian , Davis Sarah , McHugh Nicholas , Sousa Jacquelyn , Khvorova Anastasia
Published: July 2020

Small interfering RNAs (siRNAs) have revolutionized the treatment of liver diseases. However, robust siRNA delivery to other tissues represents a major technological need. Conjugating lipids (e.g. docosanoic acid, DCA) to siRNA supports extrahepatic delivery, but tissue accumulation and gene silencing efficacy are lower than that achieved in liver by clinical-stage compounds. The chemical structure of conjugated siRNA may significantly impact invivo efficacy, particularly in tissues with lower compound accumulation. Here, we report the first systematic evaluation of the impact of siRNA scaffold—i.e. structure, phosphorothioate (PS) content, linker composition—on DCA-conjugated siRNA delivery and efficacy in vivo. We found that structural asymmetry (e.g. 5- or 2-nt overhang) has no impact on accumulation, but is a principal factor for enhancing activity in extrahepatic tissues. Similarly, linker chemistry (cleavable versus stable) altered activity, but not accumulation. In contrast, increasing PS content enhanced accumulation of asymmetric compounds, but negatively impacted efficacy. Our findings suggest that siRNA tissue accumulation does not fully define efficacy, and that the impact of siRNA chemical structure on activity is driven by intracellular re-distribution and endosomal escape. Fine-tuning siRNA chemical structure for optimal extrahepatic efficacy is a critical next step for the progression of therapeutic RNAi applications beyond liver.
Healthcare Professionals’ Beliefs, Attitudes, Knowledge, and Behavior Around Vaping in Pregnancy and Postpartum: A Qualitative Study
Authors: Hunter Abby , Yargawa Judith , Notley Caitlin , Ussher Michael , Bobak Alex , Murray Rachael L , Nath Srabani , Cooper Sue
Published: July 2020

Introduction

Finding effective ways to help pregnant women quit smoking and maintain long-term abstinence is a public health priority. Electronic cigarettes (ie, vaping) could be a suitable cessation tool in pregnancy for those who struggle to quit; however, healthcare professionals (HCP) must be informed about these devices to offer appropriate advice. This study used the Capability, Opportunity, Motivation, and Behavior (COM-B) model and Theoretical Domains Framework (TDF) to explore HCP attitudes towards vaping in pregnancy and postpartum; beliefs about the health risks of vaping; perceived barriers and facilitators of vaping in pregnancy; knowledge of current guidelines and policies; and training needs.

Methods

Interviews (n = 60) were conducted with midwives (n = 17), health visitors (n = 10), general practitioners (n = 15) and stop smoking specialists (n = 18) across the United Kingdom. Interview transcriptions were analyzed thematically using the framework approach and the COM-B.

Results

Discussing vaping as a tool for quitting smoking in pregnancy was prevented by a lack of capability (limited knowledge of vaping, lack of training in smoking cessation); lack of opportunity (restricted by organizational policies and guidelines, lack of time and financial issues impacting on training), and negative social influences (sensationalist media and stigma associated with vaping in pregnancy); and lack of motivation (fear of future litigation and comebacks should adverse effects from vaping arise).

Conclusions

Factors related to capability, opportunity, and motivation were identified that influence HCPs attitudes and behaviors towards vaping in pregnancy. Gaps in knowledge and training needs were identified, which could inform the development of targeted vaping training.

Implications

Vaping could be suitable in pregnancy for those struggling to quit smoking. However, HCPs must be informed about these devices to offer appropriate advice. These data extend our knowledge of factors influencing HCP attitudes and behaviors towards vaping in pregnancy. Generally, vaping was perceived as safer than cigarettes, but a perceived lack of evidence, health and safety risks, dependency, and regulation issues were concerning. Considering our findings, greater efforts are needed to ensure HCPs are sufficiently informed about vaping and guidelines available. More importance should be placed on training for all HCPs who have contact with pregnant women.
Diagnostic accuracy of interleukin-27 in tuberculous pleurisy: a systematic review and meta-analysis
Authors: Zhang Q , Ma Y , Zhang M , Wang Y , Wu W
Published: July 2020

Objective

This study aimed to conduct a systematic review of the diagnostic value of interleukin-27 (IL-27) for tuberculous pleurisy (TP).

Methods

Literature on IL-27 diagnosis of TP was retrieved and screened from six databases (four English databases and two Chinese databases). The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and summary receiver operating characteristic curve (SROC) were measured to assess accurately the comprehensive evaluation of IL-27 for TP.

Results

Eleven studies with a total of 1454 patients were identified in the analysis. The combined diagnostic value of IL-27 for TP was as follows: sensitivity of 0.95 (95% confidence interval [CI]: 0.93–0.97), specificity of 0.91 (95% CI: 0.89–0.92), positive likelihood ratio of 13.99 (95% CI: 7.01–27.93), negative likelihood ratio of 0.07 (95% CI: 0.05–0.10), diagnostic odds ratio of 275.20 (95% CI: 112.83–671.23) and area under the SROC of 0.9830.

Conclusion

IL-27 has an excellent diagnostic value for TP and could be used as a diagnostic biomarker for TP.
Efficacy and serious adverse events profile of the adjuvanted recombinant zoster vaccine in adults with pre-existing potential immune-mediated diseases: a pooled post hoc analysis on two parallel randomized trials
Authors: Dagnew Alemnew F , Rausch Debora , Hervé Caroline , Zahaf Toufik , Levin Myron J , Schuind Anne ,   for the ZOE-50/70 study group
Published: July 2020

Abstract Objective

In the ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials, the adjuvanted recombinant zoster vaccine (RZV) demonstrated ≥90% efficacy in preventing herpes zoster (HZ) in all age groups ≥50 years. Given the increased HZ risk associated with certain underlying autoimmune diseases or their treatment regimes, we conducted a post hoc analysis of RZV’s efficacy against HZ and safety profile [specifically, the occurrence of serious adverse events (SAEs)] in ZOE-50/70 participants who reported pre-existing potential immune-mediated diseases (pIMDs) at enrolment and were not on immunosuppressive therapies.

Methods

Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomized to receive two doses of RZV or placebo 2 months apart. In this subgroup analysis of participants with at least one pIMD at enrolment, the efficacy was calculated for two-dose recipients who did not develop confirmed HZ before 30 days post-dose 2. SAE occurrence was evaluated for all participants who received at least one dose.

Results

Of the 14 645 RZV and 14 660 placebo recipients from the ZOE-50/70 studies, 983 and 960, respectively, reported at least one pre-existing pIMD at enrolment and were included in these analyses. The most frequent pre-existing conditions were psoriasis, spondyloarthropathy and RA. Efficacy against HZ was 90.5% (95% CI: 73.5, 97.5%) overall with the lowest being 84.4% (95% CI: 30.8, 98.3%) in the 70–79-year-old age group. SAEs and fatal SAEs were similar between RZV and placebo recipients.

Conclusion

In ZOE-50/70 participants with pre-existing pIMDs, RZV was highly efficacious against HZ and SAE incidence was similar between RZV and placebo recipients.

Trial registration

ClinicalTrials.gov, https://clinicaltrials.gov, NCT01165177 (ZOE-50), NCT01165229 (ZOE-70).
Prevalence, outcome and management of patients with SLE and secondary antiphospholipid antibody syndrome after aPL seroconversion
Authors: Zen Margherita , Loredo Martinez Marta , Benvenuti Francesco , Gatto Mariele , Saccon Francesca , Larosa Maddalena , Iaccarino Luca , Doria Andrea
Published: July 2020

Objective

The withdrawal of oral anticoagulation (OAC) in patients with SLE and secondary aPL syndrome (SAPS) who become seronegative has not been clearly investigated to date. Our aim was to evaluate the prevalence of aPL seroconversion and the prognosis of SLE patients with SAPS who withdrew OAC after aPL negativization.

Methods

We retrospectively analysed data of all SLE patients (ACR criteria) with SAPS (Sydney criteria) prospectively followed-up in our clinic. aPL seroconversion was defined as negativization of lupus anticoagulant, aCL, and anti-β2glycoprotein-1 antibodies on two or more consecutive measurements, at least 12 weeks apart. OAC discontinuation was defined as the definitive withdrawal of all anticoagulants.

Results

Fifty-five out of 513 (10.7%) SLE patients had vascular SAPS. Sixteen patients (29.1%) became aPL seronegative during follow-up. Immunosuppressive therapy predicted aPL negativization (odds ratio 5.211, 95%CI 1.341, 20.243), whereas APS diagnosis prior to that of SLE (odds ratio 0.078, 95%CI 0.008, 0.799) and triple-positive profile (odds ratio 0.264, 95%CI 0.115, 0.609) were negative predictors of aPL negativization. OAC was discontinued in 13/55 patients (23.6%), after a median follow-up of 45 months (range 1–276) from aPL seroconversion. SLE-related modifiable risk factors for thrombosis were observed in 10/13 patients (77%) at the time of the thrombotic event. No thrombotic recurrences were observed during a mean follow-up time of 44 (19) months from OAC discontinuation.

Conclusions

Our results suggest that OAC can be safely discontinued in SLE patients who became persistently seronegative for aPL, at least when aPL-related thrombotic events occurred in presence of other thrombotic risk factors.
Dopamine Functioning and Child Externalizing Behavior: A Longitudinal Analysis of Polygenic Susceptibility to Parenting
Authors: Fischer Karen , van den Akker Alithe L. , Larsen Helle , Jorgensen Terrence D. , Overbeek Geertjan
Published: July 2020

Objective:

This study investigated how genetic susceptibility may affect children's sensitivity to parenting practices in their development of externalizing behavior. We created a continuous polygenic index composed of 5 dopamine polymorphisms to investigate the moderating role of dopamine-related genes in shaping parent-child gene-by-environment (Gc×E) interactions. Accumulating research supports that differences in children's dopamine neurotransmission make certain children more susceptible to both negative and positive parenting practices, a “for-better and for-worse” effect.

Methods:

Data from a 3-wave longitudinal study (4 months between waves) on 190 at-risk families with children aged 4 to 8 were used to investigate whether a heightened polygenic index score amplified the associations between negative and positive parenting and later children's externalizing behavior. Parenting practices and child externalizing behavior were assessed by parent-reported questionnaires.

Results:

Findings were not in line with the expectation that there was a stronger association between positive and negative parenting and later externalizing behavior for children with higher scores on the polygenic susceptibility index. Rather, children with a lower score on the polygenic susceptibility index showed more later externalizing behavior in response to positive parenting behavior, whereas for children with a higher score on the polygenic index, positive parenting was predictive of relatively lower levels of later child externalizing behavior.

Conclusion:

The results indicate that not only are children with higher but also lower scores on the polygenic index sensitive to parenting, they suggest that different phenotypical characteristics related to reward processing might underlie these genetic susceptibilities to parenting practices.
U-shaped relationship between pre-operative plasma fibrinogen levels and severe peri-operative bleeding in cardiac surgery
Authors: Mion Stefano , Duval Benoît , Besnard Thibaut , Darné Bernadette , Mouton Christine , Jecker Olivier , Labrousse Louis , Remy Alain , Zaouter Cédrick , Ouattara Alexandre
Published: July 2020

BACKGROUND

An inverse linear relationship has been reported between pre-operative fibrinogen levels and postoperative blood loss in cardiac surgery. However, recently high pre-operative fibrinogen levels have also been reported to be associated with increased blood transfusion and re-operation.

OBJECTIVE

We tested the hypothesis that the relationship between pre-operative fibrinogen levels and severe peri-operative bleeding is not linear.

DESIGN

A large-scale (n = 3883) single-centre retrospective study.

SETTING

A tertiary care teaching hospital.

PATIENTS

We analysed data from our institutional database which includes all patients above 18 years who underwent on-pump cardiac surgery through a sternotomy between September 2010 and May 2014.

MAIN OUTCOME MEASURES

Peri-operative severe bleeding adapted from the Universal Definition of Peri-operative Bleeding, class 3 or 4. The relationship between pre-operative fibrinogen levels and peri-operative severe bleeding was analysed by binary logistic regression. A cubic B-spline transformation was used to estimate the relationship between pre-operative fibrinogen level associated with excessive peri-operative bleeding.

RESULTS

Severe peri-operative bleeding was observed in 957 (24.6%) patients. An L-shaped relationship was observed between pre-operative fibrinogen levels and 24-h postoperative blood loss. The relationship between pre-operative fibrinogen levels and severe peri-operative bleeding (i.e. Universal Definition of Peri-operative Bleeding class 3 or 4) was U-shaped: the risk of severe peri-operative bleeding bottomed at 3.3 g l−1 when the upward sloping curve started at 5.8 g l−1 with a steeper increase above 8.2 g l−1.

CONCLUSION

We reported a U-shaped relationship between severe peri-operative bleeding and pre-operative fibrinogen levels. While a low-level of fibrinogen appears to be associated with a high risk of bleeding, a high level does not necessarily protect the patient against such a risk and could even be a risk factor for peri-operative bleeding.
Novel antibody–drug conjugates: current and future roles in gynecologic oncology
Authors: Tymon-Rosario Joan , Zeybek Burak , Santin Alessandro D.
Published: July 2020

Purpose of review

Antibody–drug conjugates (ADCs) represent a new class of drugs that combine a surface receptor-targeting antibody linked to a cytotoxic molecule. This review summarizes the current literature demonstrating their tremendous promise as therapeutic agents in the treatment of aggressive gynecologic malignancies.

Recent findings

Several antigens have proven to be differentially overexpressed in a variety of gynecologic tumors when compared with normal surrounding tissue and serve as novel targets for ADC therapy. In the last few years HER2/neu, folic acid-alpha (FRα) and Trop-2 overexpression have been exploited as excellent targets by novel ADCs such as Trastuzumab emtansine (T-DM1), SYD985, IMGN853 (Mirvetuximab soravtansine) and Sacituzumab govitecan (SG, IMMU-132) in multiple tumors including ovarian, endometrial and cervical cancers. Although the selectivity of ADCs with noncleavable linkers (i.e. T-DM1) has shown negligible effect on surrounding antigen negative cells, those ADCs with cleavable linkers (i.e. SYD985, IMGN853 and SG) may kill both antigen-positive target cells and surrounding antigen-negative cells via the bystander effect.

Preclinical data strongly supports these ADCs and ongoing clinical trials will shed further light into the potential of making these drugs part of current standard practice and providing our patients with a higher level of personalized cancer care.
Successful Treatment of Pandrug-resistant Klebsiella pneumoniae Infection With Ceftazidime-avibactam in a Preterm Infant
Authors: Coskun Yesim , Atici Serkan
Published: July 2020

Pandrug-resistant (PDR) bacterial infections in intensive care units are emerging as a severe problem. Therefore, new antibiotic options are urgently needed for the treatment of PDR infections in pediatric age groups, especially neonates. Herein, we report a 25 days old preterm neonate successfully treated with ceftazidime-avibactam due to a urinary tract infection caused by PDR Klebsiella pneumoniae. We aimed to describe our experiences about the safety and efficacy of ceftazidime-avibactam treatment.
Duration of Respiratory and Gastrointestinal Viral Shedding in Children With SARS-CoV-2: A Systematic Review and Synthesis of Data
Authors: Xu Cecilia L. H. , Raval Manjri , Schnall Jesse A. , Kwong Jason C. , Holmes Natasha E.
Published: July 2020

Background:

Children with coronavirus disease 2019 (COVID-19) are more likely to have mild or no symptoms compared with adults and may represent important vectors for transmitting the virus. Little is known about the duration of respiratory and gastrointestinal viral shedding in children with COVID-19.

Objective:

To determine the average shedding times of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via the respiratory and gastrointestinal tracts in children.

Methods:

We performed a systematic search of Ovid MEDLINE, Embase and Cochrane CENTRAL databases for studies reporting real-time reverse transcriptase polymerase chain reaction (rt-PCR) results in children with COVID-19, then extracted and synthesized data on duration of viral shedding from symptom onset in respiratory and gastrointestinal samples.

Results:

Based on data compiled from 69 pediatric cases, the duration of viral shedding through the respiratory tract is up to 24 days from symptom onset with a mean of 11.1 ± 5.8 days. Of the children who underwent testing with stool PCR, rectal swab or anal swab, 86% returned a positive result. The mean duration of viral shedding via the gastrointestinal tract was 23.6 ± 8.8 days from symptom onset. In 89% of cases, viral shedding via the gastrointestinal tract persisted after nasopharyngeal or throat swabs became negative, for as long as 4 weeks.

Conclusions:

To our knowledge, this is the first attempt to systematically review the duration of respiratory and gastrointestinal viral shedding of SARS-CoV-2 in pediatric patients. These findings may have important implications for infection control strategies during the COVID-19 pandemic.
Persistent Barriers to the Use of Long-Acting Injectable Antipsychotics for the Treatment of Schizophrenia
Authors: Lindenmayer Jean-Pierre , Glick Ira D. , Talreja Hiteshkumar , Underriner Michael
Published: July 2020

Purpose/Background

One of the major challenges in the treatment of schizophrenia is nonadherence, defined as the failure to take medications as prescribed. Nonadherence is a strong predictor of symptom relapse, hospital readmission, and poorer long-term outcome. Although long-acting injectable antipsychotics (LAIs) have been found to be superior to their oral analogs at reducing relapse in large-scale meta-analyses, their prevalence seldom exceeds 30% even in populations with a history of nonadherence. We review multiple barriers to the use of LAI utilization and suggest strategies to address them.

Methods/Procedures

We searched for the following terms: long-acting injectable/depot antipsychotics, schizophrenia, barriers, and attitude/perception in both the PubMed search index and Google scholar from 1995 to 2018. A total of 329 studies were selected, of which data from 13 were reviewed for this article. Only peer-reviewed studies, randomized controlled trials, systematic reviews, and meta-analyses that describe barriers to using LAIs were included.

Findings/Results

Several barriers to using LAIs were identified. These are organized into 3 overarching categories: those related to the clinician; those related to the patient; and systems barriers. Clinician factors include the perception of LAIs as coercive, fears of not being able to control the dose, as well as current practice patterns and guidelines. Patient factors include perception of the injection as painful or intrusive, general lack of knowledge, and a sense of coerciveness. For each identified barrier, we propose potential solutions.

Implications/Conclusions

We identified multiple barriers to using LAIs in patients with schizophrenia. Specific strategies are suggested for overcoming each of these barriers.
Elevated Venous to Arterial Carbon Dioxide Gap and Anion Gap Are Associated with Poor Outcome in Cardiogenic Shock Requiring Extracorporeal Membrane Oxygenation Support
Authors: McDonald Charles I. , Brodie Daniel , Schmidt Matthieu , Hay Karen , Shekar Kiran
Published: July 2020

Optimal management of cardiogenic shock requiring extracorporeal membrane oxygenation (ECMO) is still an evolving area in which assessment and optimization of the microcirculation may be critically important. We hypothesized that the venous arterial carbon dioxide gap (P(v-a)CO2 gap); the ratio of this gap to arterio-venous oxygen content (P(v-a)CO2/C(a-v)O2 ratio) and the anion gap would be early indicators of microcirculatory status and useful parameters for outcome prediction during ECMO support. We retrospectively reviewed 31 cardiogenic shock patients requiring veno-arterial ECMO, calculating P(v-a)CO2 gap and P(v-a)CO2/C(a-v)O2 ratios in the first 36 hours and the final 24 hours of ECMO support. Sixteen patients (52%) survived and 15 (48%) died. After 24 hours of ECMO support, the P(v-a)CO2 gap (4.9 ± 1.5 vs. 6.8 ± 1.9 mm Hg; p = 0.004) and anion gap (5.2 ± 1.8 vs. 8.7 ± 2.7 mmol/L; p < 0.001) were significantly higher in non-survivors. In the final 24 hours of ECMO support, the P(v-a)CO2 gap (3.5 ± 1.6 vs. 10.5 ± 3.2 mm Hg; p < 0.001), P(v-a)CO2/C(a-v)O2 ratio (1.1 ± 0.5 vs. 2.7 ± 1.0; p < 0.001), anion gap (5.1 ± 3.0 vs. 9.3 ± 5.9 mmol/L; p = 0.02), and lactate (median 1.0 [interquartile range {IQR}: 0.7–1.5] vs. 2.8 [IQR: 1.7–7.7] mmol/L; p = <0.001) were all significantly lower in survivors. Increasing P(v-a)CO2 gap and increasing anion gap were significantly associated with increased risk of mortality. Optimum cut-points for prediction of mortality were 6 mm Hg for P(v-a)CO2 gap in combination with an anion gap above 6 mmol/L in the first 24 hours of ECMO in patients with cardiogenic shock requiring ECMO.
Metabolic and cardiovascular outcomes of bariatric surgery
Authors: Iqbal Zohaib , Adam Safwaan , Ho Jan H. , Syed Akheel A. , Ammori Basil J. , Malik Rayaz A. , Soran Handrean
Published: July 2020

Purpose of review

Bariatric surgery is an effective therapy for morbid obesity that also improves weight-related metabolic parameters and reduces morbidity and mortality. The purpose of this review is to consolidate our current understanding of metabolic, macrovascular and microvascular benefits of bariatric surgery and to provide an update.

Recent findings

Early resolution of insulin resistance and type 2 diabetes mellitus (T2DM) varies by type of bariatric surgery and appears to be mediated by changes in secretion of gut hormones, metabolism of bile acids, expression of glucose transporters and the gut microbiome. Dyslipidaemia, atherosclerosis, microvascular complications of obesity and diabetes, systemic and tissue-level inflammation show evidence of regression and hypertension improves significantly after bariatric surgery.

Bariatric surgery leads to improvements in obesity-related metabolic comorbidities such as dyslipidaemia, HDL functionality, hypertension, T2DM, insulin resistance and inflammation. It slows the atherosclerotic process and reduces cardiovascular and all-cause mortality. Recent data have demonstrated regression of the microvascular complications of obesity and diabetes including the regeneration of small nerve fibres. The magnitude of change in short-term metabolic effects depends on the surgical procedure whilst longer term effects are related to the amount of sustained excess weight loss.
Plexiform Myofibroblastoma
Authors: Papke David J. , Al-Ibraheemi Alyaa , Fletcher Christopher D.M.
Published: July 2020

The spectrum of benign superficial fibroblastic/myofibroblastic tumors continues to expand and includes entities such as plexiform fibrohistiocytic tumor, dermatomyofibroma and fibroblastic connective tissue nevus. Here, we describe a seemingly distinctive group of lesions which we have labeled “plexiform myofibroblastoma” (PM). PM is a rare superficial mesenchymal tumor of fibroblastic/myofibroblastic lineage that predominantly occurs in children and young adults. Thirty-six cases from the consultation archives of one of the authors have been studied to characterize the clinicopathologic characteristics of PM. 19 patients (53%) were female and 17 were male, with age at presentation ranging from congenital (2 cases) to 50 years of age (median: 9.5 y). Three patients had multiple lesions. Males tended to develop tumors during childhood (median: 2 y; range: congenital—37 y), while in females the age distribution was relatively uniform from childhood through adulthood (median age: 25 y; range: 4 mo to 50 y). Most tumors occurred in truncal locations (25/40), including the back (11), anterolateral chest wall (4), axilla (4), abdominal wall (4), perineum (1) and suprapubic region (1). Other tumor sites were the neck (10/40), occiput (2), lower extremity (2) and breast (1). The average greatest dimension was 2.7±1.7 cm (range: 0.6 to 8 cm). Three male patients, 2 of whom were brothers, presented between 6 months and 1 year of age with multiple lesions variably involving the back, occiput and axillae; these lesions spontaneously regressed after being present for about 2 years, with no evidence of recurrence at a mean follow-up of 11.4±3.2 years. Histologically, PM was composed of plexiform fascicles of fibroblastic/myofibroblastic spindle cells that ramify through the subcutis and reticular dermis. The bland neoplastic cells had indistinct cell borders, palely eosinophilic cytoplasm and ovoid or tapered nuclei. There was no histiocytoid component in any case, and no cases contained osteoclast-like giant cells. Twelve of thirty-four (35%) reviewed cases showed at least focal keloidal hyalinization, 6/34 (18%) contained somewhat fasciitis-like areas and 6/34 (18%) contained focal myxoid stroma. Immunohistochemical studies were positive for SMA (27/32 cases), desmin (9/21) and CD34 (13/24) and negative for β-catenin (0/14) and S-100 (0/22). EMA was weakly positive in 2/15 cases. An FGFR2 M535L tyrosine kinase domain variant of unknown significance was detected in 1/7 sequenced cases, and no somatic alterations, copy number alterations or gene fusions were detected in the other 6. Clinical follow-up data were available for 16/36 patients (44%; median duration: 5.5 y). Although most excisions had positive margins (11/16), only 1 patient developed a local recurrence 4 years after initial excision. No tumors metastasized. PM is a benign tumor with characteristic histology, epidemiology and anatomic site distribution. Because PM rarely recurs, a watchful waiting approach would be reasonable for lesions excised with positive margins.
Arcanobacterium bovis sp. nov., isolated from the milk of a cow with mastitis
Authors: Sammra Osama , Foster Geoffrey , Hassan Abdulwahed Ahmed , Alssahen Mazen , Lämmler Christoph , Glaeser Stefanie P. , Kämpfer Peter , Busse Hans-Jürgen , Borowiak Maria , Malorny Burkhard , Ritchie Catriona M. , Prenger-Berninghoff Ellen , Abdulmawjood Amir
Published: July 2020

A polyphasic taxonomic study was performed on an unidentified

Arcanobacterium

-like Gram-stain-positive bacterium designated strain C605018/01/1T isolated from a milk sample collected from the udder of a cow at post mortem. Comparative 16S rRNA gene sequencing showed that the bacterium belonged to the genus

Arcanobacterium

and was most closely related to the type strain of

Arcanobacterium pluranimalium

(99.76 %); sequence similarities to all other

Arcanobacterium

species were below 97 %. The wet-lab DNA–DNA hybridization values among strain C605018/01/1T and

A. pluranimalium

DSM 13483ᵀ were low, 16.9 % (reciprocal, 49.8 %). Pertaining to the whole genome sequence with a total length of 2.02 Mb and 1654 protein counts, the novel strain C605018/01/01T displayed a G+C content of 51.6 % mol%. The presence of the major menaquinone MK-9(H4) supported the affiliation of this strain to the genus

Arcanobacterium

. The polar lipid profile consisted of the major components diphosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol-mannoside and unidentified glycolipid and aminophospholipids. Based on these results it is proposed that strain C605018/01/1T should be classified as representing a novel species, Arcanbacterium bovis sp. nov. The type strain C605018/01/1T (CCUG 45425T=DSM 107286T=BCCM/LMG 30783T)
Absence of classical and atypical (H- and L-) BSE infectivity in the blood of bovines in the clinical end stage of disease as confirmed by intraspecies blood transfusion
Authors: Balkema-Buschmann Anne , Ziegler Ute , Priemer Grit , Tauscher Kerstin , Köster Frauke , Ackermann Ivett , Fatola Olanrewaju I. , Balkema Daniel , Schinköthe Jan , Hammerschmidt Bärbel , Fast Christine , Ulrich Reiner , Groschup Martin H.
Published: July 2020

While the presence of bovine spongiform encephalopathy (BSE) infectivity in the blood of clinically affected sheep has been proven by intraspecies blood-transfusion experiments, this question has remained open in the case of BSE-affected cattle. Although the absence of infectivity can be anticipated from the restriction of the agent to neuronal tissues in this species, evidence for this was still lacking. This particularly concerns the production and use of medicinal products and other applications containing bovine blood or preparations thereof. We therefore performed a blood-transfusion experiment from cattle in the clinical end stage of disease after experimental challenge with either classical (C-BSE) or atypical (H- and l-) BSE into calves at 4–6 months of age. The animals were kept in a free-ranging group for 10 years. Starting from 24 months post-transfusion, a thorough clinical examination was performed every 6 weeks in order to detect early symptoms of a BSE infection. Throughout the experiment, the clinical picture of all animals gave no indication of a BSE infection. Upon necropsy, the brainstem samples were analysed by BSE rapid test as well as by the highly sensitive Protein Misfolding Cyclic Amplification (PMCA), all with negative results. These results add resilient data to confirm the absence of BSE infectivity in the donor blood collected from C-, H- and l-BSE-affected cattle even in the final clinical phase of the disease. This finding has important implications for the risk assessment of bovine blood and blood products in the production of medicinal products and other preparations.