bluuebunny/crossref_metadata_2025 huggingface dataset:
High-energy ion (He+, Si++, Ga+, Au++) interactions with PMMA in ion beam lithography
Authors: Zhang Lei , Thomas Joseph P , Guan Xiaoyi , Heinig Nina F , Leung Kam Tong
Published: April 2020

Resist-based ion beam lithography has been studied by exposing different species of ions (He+, Si++, Ga+ and Au++) on 700 and 2000 Å thick poly(methyl methacrylate) (or PMMA) films supported on Si substrates. By comparing the resist sensitivities to different ions and the cross-sectional shapes of the developed features with the simulation outputs from the TRIM (TRansport of Ions in Matter) software, long-chain scissoring in PMMA can be largely attributed to ion-initiated electron cascades (as evaluated by ion energy loss to the electrons) and recoil atom cascades (as evaluated by vacancy distribution in TRIM). The ion-initiated electron cascades contribute more to the resist sensitivity for the lighter ions, while the recoil atom cascades are more important for the heavier ions. A proportional relation between the resist sensitivity and the product of the ion energy loss to electrons and vacancy number is obtained semi-empirically for heavy ions. The He+ ion is the only ion species that can travel through and therefore expose the entire 2000-Å thick PMMA resist film, while the heaviest ion, Au++, provides the highest resist sensitivity. The effective energy and momentum impartment to the resist by the ion, as revealed by recoil atom cascades and vacancy formation, is important to significantly expanding the material types suitable for ion beam lithography.
Efficient photocatalytic inactivation of E. coli by Mn-CdS/ZnCuInSe/CuInS2 quantum dots-sensitized TiO2 nanowires
Authors: Geng Hongchao , Jiang Ning , Li Chenyi , Zhu Xingqi , Qiao Yan , Cai Qingyun
Published: April 2020

A novel visible light-driven photocatalyst (represented as Mn-CdS/ZCISe/CIS/TiO2) for the passivation of E. coli was prepared with TiO2 nanowires as support and using CuInS2 (CIS) and ZnCuInSe (ZCISe) quantum dots (QDs), as well as Mn-doped CdS (Mn-CdS) nanoparticles (NPs) as sensitizers. The use of CIS and ZCISe QDs and Mn-CdS NPs extends the light harvest region to visible light. The photoelectric conversion efficiency was consequently improved, with a photocurrent density of 12.5 mA cm−2, about 60 times that of pure TiO2 nanowires. The germicidal efficiency of the photocatalyst was assessed by passivation of E. coli, 96% bacteria in 50 ml 105 colony forming units (CFU) ml−1 solution were killed within 50 min. Besides the high efficiency, the composite has good stability and satisfactory recycling performance. The antibiotic mechanism was also performed by using photoluminescence and a scavenging agent of different active matter, revealing that the photo-generated holes play a major role in the sterilization process.
Projection micro stereolithography based 3D printing and its applications
Authors: Ge Qi , Li Zhiqin , Wang Zhaolong , Kowsari Kavin , Zhang Wang , He Xiangnan , Zhou Jianlin , Fang Nicholas X
Published: April 2020

Projection micro stereolithography (PμSL) is a high-resolution (up to 0.6 μm) 3D printing technology based on area projection triggered photopolymerization, and capable of fabricating complex 3D architectures covering multiple scales and with multiple materials. This paper reviews the recent development of the PμSL based 3D printing technologies, together with the related applications. It introduces the working principle, the commercialized products, and the recent multiscale, multimaterial printing capability of PμSL as well as some functional photopolymers that are suitable to PμSL. This review paper also summarizes a few typical applications of PμSL including mechanical metamaterials, optical components, 4D printing, bioinspired materials and biomedical applications, and offers perspectives on the directions of the further development of PμSL based 3D printing technology.
What We Talk About When We Talk About Binge Drinking: Towards an Integrated Conceptualization and Evaluation
Authors: Maurage Pierre , Lannoy Séverine , Mange Jessica , Grynberg Delphine , Beaunieux Hélène , Banovic Ingrid , Gierski Fabien , Naassila Mickaël
Published: April 2020

Rationale

Binge drinking (BD), characterized by recurring alternations between intense intoxication episodes and abstinence periods, is the most frequent alcohol consumption pattern in youth and is growing in prevalence among older adults. Many studies have underlined the specific harmful impact of this habit by showing impaired abilities in a wide range of cognitive functions among binge drinkers, as well as modifications of brain structure and function.

Aims

Several controversies and inconsistencies currently hamper the harmonious development of the field and the recognition of BD as a specific alcohol consumption pattern. The main concern is the absence of consensual BD conceptualization, leading to variability in experimental group selection and alcohol consumption evaluation. The present paper aims at overcoming this key issue through a two-step approach.

Methods and conclusions

First, a literature review allows proposing an integrated BD conceptualization, distinguishing it from other subclinical alcohol consumption patterns. Six specific characteristics of BD are identified, namely, (1) the presence of physiological symptoms related to BD episodes, (2) the presence of psychological symptoms related to BD episodes, (3) the ratio of BD episodes compared to all alcohol drinking occasions, (4) the frequency of BD episodes, (5) the consumption speed and (6) the alternation between BD episodes and soberness periods. Second, capitalizing on this conceptual clarification, we propose an evaluation protocol jointly measuring these six BD characteristics. Finally, several research perspectives are presented to refine the proposed conceptualization.
‘Yes, Security, there is security. But other than that, nothing.’: An empirical inquiry into the ‘everyday (in)security’ of Syrian and Iraqi urban refugees in Jordan
Authors: Ajil Ahmed , Jendly Manon , Campistol Mas Claudia
Published: April 2020

Scholarship on security has recently seen a shift from traditionally state-centric, elitist and objectivist conceptions of ‘security’ towards human-centred perspectives, which put emphasis on forms of ‘vernacular’ and ‘everyday’ security, and promote bottom-up empirical inquiries to further our understand of what security looks like ‘from below’. There remains, however, a dearth of empirical material exploring ‘everyday security’. In this paper, we are studying the ‘everyday security’ of a particularly securitized group, namely refugees. In-depth semi-structured interviews were conducted between 2016 and 2017 with 23 Syrian and Iraqi urban refugees living in the Jordanian cities of Amman and Mafraq. We analyse how they understand and perceive their own (in)security: we do so by focusing, retrospectively, on the factors and events that led up to their flight from their home country (‘pre-flight period’) on the one hand and those shaping their present life in exile in Jordanian urban areas (‘post-flight period’) on the other. Our findings indicate that, while pre-flight insecurity is mostly defined around existential threats to physical integrity, post-flight insecurity is shaped by a more diffuse form of insecurity, resulting from the legal, economic, social and political limbo they are stuck in.
Methylephedrine-induced heart failure in a habitual user of paediatric cough syrup: a case report
Authors: Suzuki Moeko , Higashi Haruhiko , Ikeda Shuntaro , Yamaguchi Osamu
Published: April 2020

Background

For relief of cold symptoms, methylephedrine is considered to be safer than ephedrine, particularly when used at the predetermined dose. It is often present in various over-the-counter (OTC) drugs for cold, including paediatric cough syrups.

Case summary

A 52-year-old man presented with worsening dyspnoea and anorexia for 2 weeks. He was a night shift worker and had been habitually taking large doses of methylephedrine-containing paediatric cough syrup for 20 years for sleep averting. On admission, his chest X-ray revealed pulmonary congestion and electrocardiogram showed sinus tachycardia with left-axis deviation. Echocardiography revealed diffuse hypokinesis with a reduced ejection fraction (EF) of 25%. The B-type natriuretic peptide level was elevated to 1092 ng/L. Even after treatment with low-dose dobutamine and furosemide in intensive care unit, right-heart catheterization demonstrated a ‘wet and cold’ profile. Coronary angiography revealed normal coronary arteries. Pathological examination by endomyocardial biopsy revealed cardiomyocyte hypertrophy with moderate interstitial and replacement fibrosis. In addition, cardiac magnetic resonance imaging revealed diffuse hypokinesis with mid-wall late gadolinium enhancement, which suggested fibrosis. Discontinuation of the cough syrup and optimal medical treatment with an angiotensin-converting enzyme inhibitor and a β blocker resulted in improvement in the heart failure symptoms to New York Class Association Class II. The EF also improved to 50% at 4 months after discharge.

Discussion

Methylephedrine is considered to have adrenergic effects; it has milder side effects on the cardiovascular system than ephedrine. However, the long-lasting excessive intake of methylephedrine, even through OTC paediatric cough syrups, has the potential to cause heart failure.
Prescription of oral anticoagulants and antiplatelets for stroke prophylaxis in atrial fibrillation: nationwide time series ecological analysis
Authors: Wu Jianhua , Alsaeed Eman S , Barrett James , Hall Marlous , Cowan Campbell , Gale Chris P
Published: April 2020

Aims

To investigate trends in the prescription of oral anticoagulants (OACs) and antiplatelet agents for atrial fibrillation (AF).

Methods and results

Prescription data for 450 518 patients with AF from 3352 General Practices in England, was obtained from the GRASP-AF registry, 2009–2018. Annualized temporal trends for OAC and antiplatelet prescription were reported according to eligibility based on stroke risk (CHADS2 or CHA2DS2-VASc scores ≥1 or >2, respectively). From 2009 to 2018, the prevalence of AF increased from 1.6% [95% confidence interval (CI) 1.5–1.7%] to 2.4% (2.3–2.5%), and for those with AF the proportion prescribed OAC increased from 47.6% to 75.0% (P-trend < 0.001; relative risk 1.57, 95% CI 1.55–1.60) and for antiplatelet decreased from 37.4% to 9.2% (P-trend < 0.001). In early-years (2009–2013), eligible patients aged ≥80 years were less likely to be prescribed OAC than patients aged <80 years [odds ratio (OR) 0.55, 95% CI 0.51–0.59 for CHADS2≥1 in 2009] (all P-trends < 0.001). This ‘OAC prescription gap’ reduced over the study period (OR 0.93, 0.90–0.96 in 2018). Whilst the prescription of direct oral anticoagulant (DOAC) as a proportion of all OAC increased from 0.1% (95% CI 0.0–0.2%) in 2011 to 58.8% (58.4–59.2%) in 2018, it was inversely associated with patient age (P-trend < 0.001) and their risk of stroke.

Conclusion

Between 2009 and 2018, in England, the use of OAC for stroke prophylaxis in AF increased, with DOAC accounting for over half of OAC uptake in 2018. Despite a reduction in the OAC-prescription gap, a new paradox exists relating to DOAC prescription for the elderly and those at higher risk of stroke.
A model for the atmospheric shock wave produced by a strong volcanic explosion
Authors: Dragoni Michele , Santoro Dalila
Published: April 2020

Atmospheric shock waves are a common phenomenon in explosive volcanic eruptions. We consider the motion of a spherical shock wave generated by a point source in the strong shock approximation. The shock front corresponds to discontinuities in the gas velocity, density, pressure and temperature, which are calculated as functions of the energy of the explosion. The problem is solved analytically for the distributions of velocity, density, pressure and temperature in the atmosphere as functions of the distance from the source. The motion of the shock wave being supersonic, the solution is valid for a few seconds after the explosion, corresponding to a distance of few kilometres. The acoustic effect of the shock wave, expressed by the peak sound pressure level, is calculated and may reach hundreds of decibels. The pressure waveform that could be recorded in the vicinity of the volcano is calculated and compared with typical waveforms in weak shock conditions. The change in the refractive index of air due to density inhomogeneity is calculated and the conditions under which a condensation cloud is formed behind the shock front are investigated.
Pmp22 super-enhancer deletion causes tomacula formation and conduction block in peripheral nerves
Authors: Pantera Harrison , Hu Bo , Moiseev Daniel , Dunham Chris , Rashid Jibraan , Moran John J , Krentz Kathleen , Rubinstein C Dustin , Won Seongsik , Li Jun , Svaren John
Published: April 2020

Copy number variation of the peripheral nerve myelin gene Peripheral Myelin Protein 22 (PMP22) causes multiple forms of inherited peripheral neuropathy. The duplication of a 1.4 Mb segment surrounding this gene in chromosome 17p12 (c17p12) causes the most common form of Charcot-Marie-Tooth disease type 1A, whereas the reciprocal deletion of this gene causes a separate neuropathy termed hereditary neuropathy with liability to pressure palsies (HNPP). PMP22 is robustly induced in Schwann cells in early postnatal development, and several transcription factors and their cognate regulatory elements have been implicated in coordinating the gene’s proper expression. We previously found that a distal super-enhancer domain was important for Pmp22 expression in vitro, with particular impact on a Schwann cell-specific alternative promoter. Here, we investigate the consequences of deleting this super-enhancer in vivo. We find that loss of the super-enhancer in mice reduces Pmp22 expression throughout development and into adulthood, with greater impact on the Schwann cell-specific promoter. Additionally, these mice display tomacula formed by excessive myelin folding, a pathological hallmark of HNPP, as have been previously observed in heterozygous Pmp22 mice as well as sural biopsies from patients with HNPP. Our findings demonstrate a mechanism by which smaller copy number variations, not including the Pmp22 gene, are sufficient to reduce gene expression and phenocopy a peripheral neuropathy caused by the HNPP-associated deletion encompassing PMP22.
Can Unified Medical Language System–based semantic representation improve automated identification of patient safety incident reports by type and severity?
Authors: Wang Ying , Coiera Enrico , Magrabi Farah
Published: April 2020

Objective

The study sought to evaluate the feasibility of using Unified Medical Language System (UMLS) semantic features for automated identification of reports about patient safety incidents by type and severity.

Materials and Methods

Binary support vector machine (SVM) classifier ensembles were trained and validated using balanced datasets of critical incident report texts (n_type = 2860, n_severity = 1160) collected from a state-wide reporting system. Generalizability was evaluated on different and independent hospital-level reporting system. Concepts were extracted from report narratives using the UMLS Metathesaurus, and their relevance and frequency were used as semantic features. Performance was evaluated by F-score, Hamming loss, and exact match score and was compared with SVM ensembles using bag-of-words (BOW) features on 3 testing datasets (type/severity: n_benchmark = 286/116, n_original = 444/4837, n_independent =6000/5950).

Results

SVMs using semantic features met or outperformed those based on BOW features to identify 10 different incident types (F-score [semantics/BOW]: benchmark = 82.6%/69.4%; original = 77.9%/68.8%; independent = 78.0%/67.4%) and extreme-risk events (F-score [semantics/BOW]: benchmark = 87.3%/87.3%; original = 25.5%/19.8%; independent = 49.6%/52.7%). For incident type, the exact match score for semantic classifiers was consistently higher than BOW across all test datasets (exact match [semantics/BOW]: benchmark = 48.9%/39.9%; original = 57.9%/44.4%; independent = 59.5%/34.9%).

Discussion

BOW representations are not ideal for the automated identification of incident reports because they do not account for text semantics. UMLS semantic representations are likely to better capture information in report narratives, and thus may explain their superior performance.

Conclusions

UMLS-based semantic classifiers were effective in identifying incidents by type and extreme-risk events, providing better generalizability than classifiers using BOW.
Identification of Unique 4-Methylmethcathinone (4-MMC) Degradation Markers in Putrefied Matrices†
Authors: Trujillo Uruena Melissa , York Rebekah , Philp Morgan , Kuzhiumparambil Unnikrishnan , Wei Zhiwen , Yun Keming , Fu Shanlin
Published: April 2020

Drug degradation as a consequence of putrefactive bacterial activity is a well-known factor that affects the identification and quantitation of certain substances of forensic interest. Current knowledge on putrefaction-mediated degradation of drugs is, however, significantly lacking. This study aimed to investigate the degradation of 4-methylmethcathinone (4-MMC or mephedrone) and to detect its degradation products in putrefied biological matrices containing 4-MMC. The bacteria species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris were grown in brain-heart infusion broth, spiked with 4-MMC and incubated at 37°C for 24 h. Postmortem human blood and fresh porcine liver macerate were also left to putrefy in sample tubes at room temperature for 1 week. Structural elucidation was based on modern spectroscopic analyses including the use of high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. All four putrefactive bacteria were capable of degrading 4-MMC extensively under the experimental conditions explored. Of particular interest was the discovery of a novel degradation product common to all four bacterial species, which was assigned as 2-hydroxy-1-(4-methylphenyl)propan-1-one (HMP) based on the spectroscopic data. This degradation product was detectable in both postmortem human blood and porcine liver samples. The stability of the identified degradation products, especially HMP, should be further investigated to assess their validity of serving as marker analytes for monitoring 4-MMC in postmortem toxicology.
The Ability of the Invasive Asian Longhorned Tick Haemaphysalis longicornis (Acari: Ixodidae) to Acquire and Transmit Rickettsia rickettsii (Rickettsiales: Rickettsiaceae), the Agent of Rocky Mountain Spotted Fever, Under Laboratory Conditions
Authors: Stanley Hannah M , Ford Shelby L , Snellgrove Alyssa N , Hartzer Kris , Smith Emily B , Krapiunaya Inna , Levin Michael L
Published: April 2020

The invasive Asian longhorned tick, Haemaphysalis longicornis Neumann, was first detected in the United States in 2017. It has since been found in 12 states, and there is concern that the tick’s parthenogenetic ability and wide variety of host species may allow for broader dissemination. Of the tick-borne diseases endemic to the United States, Rocky Mountain spotted fever (RMSF), a rapidly progressive and potentially fatal disease caused by Rickettsia rickettsii, is the most severe. There is considerable geographical overlap between spotted fever rickettsioses cases, which include RMSF, and the currently known distribution of H. longicornis, providing the potential for this tick to encounter this pathogen. We have evaluated the ability of H. longicornis to acquire and transmit R. rickettsii under laboratory conditions. Haemaphysalis longicornis as larvae and nymphs acquired the pathogen while feeding on infected guinea pigs. The infection persisted through every life stage, all of which were able to transmit R. rickettsii to naïve hosts. The pathogen was also transmitted at a low frequency between generations of H. longicornis through the ova. While H. longicornis was demonstrated to be a competent vector for R. rickettsii under laboratory conditions, the probability of its involvement in the maintenance and transmission of this pathogen in nature, as well as its potential impact on human health, requires further study.
Media Prescriptions: Exploring the Therapeutic Effects of Entertainment Media on Stress Relief, Illness Symptoms, and Goal Attainment
Authors: Prestin Abby , Nabi Robin
Published: April 2020

Rooted in theories of positive emotions, this research asks the question: Can media be prescribed to help mitigate the negative effects of stress on well-being? Over the course of 5 days, participants were assigned 5-minute YouTube videos pilot tested to evoke hope, amusement, or calmness. Compared to a no-message control, each media group reported reduced stress during the intervention. All groups also reported reduced stress and fewer illness symptoms a few days after the intervention’s conclusion. Although all media conditions calmed stress experiences, only the videos designed to evoke hope via underdog narratives generated increases in approach motivation and goal attainment, explained primarily by felt hope (vs. self-efficacy). This research demonstrates that positive emotions induced by media exposure can generate both psychological and physical benefits, and that discrete emotions can exert unique patterns of influence. Implications for the application of media prescriptions are considered.
Challenging diagnosis of chronic cerebral fungal infection: Value of (1→3)-ß-D-glucan and mannan antigen testing in cerebrospinal fluid and of cerebral ventricle puncture
Authors: Hobson Claire A , Desoubeaux Guillaume , Carvalho-Schneider Claudia , Destrieux Christophe , Cottier Jean-Philippe , Garot Denis , Le Brun Cécile , Maakaroun Zoha , Lemaignen Adrien , Bailly Éric , Bernard Louis
Published: April 2020

Primary fungal infection of the central nervous system (CNS) is rare but often associated with severe prognosis. Diagnosis is complicated since cerebrospinal fluid (CSF) samples obtained from lumbar puncture usually remain sterile. Testing for fungal antigens in CSF could be a complementary diagnostic tool. We conducted such measurements in CSF from patients with CNS fungal infection and now discuss the usefulness of ventricular puncture. Mannan and (1→3)ß-D-glucan (BDG) testing were retrospectively performed in CSF samples from three patients with proven chronic CNS fungal infection (excluding Cryptococcus), and subsequently compared to 16 controls. Results from lumbar punctures and those from cerebral ventricles were confronted. BDG detection was positive in all the CSF samples (from lumbar and/or ventricular puncture) from the three confirmed cases. In case of Candida infection, mannan antigen measurement was positive in 75% of the CSF samples. In the control group, all antigen detections were negative (n = 15), except for one false positive. Faced with suspected chronic CNS fungal infection, measurement of BDG levels appears to be a complementary diagnostic tool to circumvent the limitations of mycological cultures from lumbar punctures. In the event of negative results, more invasive procedures should be considered, such as ventricular puncture.
Chemodynamics of barred galaxies in cosmological simulations: On the Milky Way’s quiescent merger history and in-situ bulge
Authors: Fragkoudi F , Grand R J J , Pakmor R , Blázquez-Calero G , Gargiulo I , Gomez F , Marinacci F , Monachesi A , Ness M K , Perez I , Tissera P , White S D M
Published: April 2020

We explore the chemodynamical properties of a sample of barred galaxies in the Auriga magnetohydrodynamical cosmological zoom-in simulations, which form boxy/peanut (b/p) bulges, and compare these to the Milky Way (MW). We show that the Auriga galaxies which best reproduce the chemodynamical properties of stellar populations in the MW bulge have quiescent merger histories since redshift z ∼ 3.5: their last major merger occurs at $t_{\rm lookback}\gt 12\, \rm Gyr$, while subsequent mergers have a stellar mass ratio of ≤1:20, suggesting an upper limit of a few per cent for the mass ratio of the recently proposed Gaia Sausage/Enceladus merger. These Auriga MW-analogues have a negligible fraction of ex-situ stars in the b/p region ($\lt 1{{\ \rm per\ cent}}$), with flattened, thick disc-like metal-poor stellar populations. The average fraction of ex-situ stars in the central regions of all Auriga galaxies with b/p’s is 3 per cent – significantly lower than in those which do not host a b/p or a bar. While the central regions of these barred galaxies contain the oldest populations, they also have stars younger than 5 Gyr (>30 per cent) and exhibit X-shaped age and abundance distributions. Examining the discs in our sample, we find that in some cases a star-forming ring forms around the bar, which alters the metallicity of the inner regions of the galaxy. Further out in the disc, bar-induced resonances lead to metal-rich ridges in the Vϕ − r plane – the longest of which is due to the Outer Lindblad Resonance. Our results suggest the Milky Way has an uncommonly quiet merger history, which leads to an essentially in-situ bulge, and highlight the significant effects the bar can have on the surrounding disc.
TW Hya: an old protoplanetary disc revived by its planet
Authors: Nayakshin Sergei , Tsukagoshi Takashi , Hall Cassandra , Vazan Allona , Helled Ravit , Humphries Jack , Meru Farzana , Neunteufel Patrick , Panic Olja
Published: April 2020

Dark rings with bright rims are the indirect signposts of planets embedded in protoplanetary discs. In a recent first, an azimuthally elongated AU-scale blob, possibly a planet, was resolved with ALMA in TW Hya. The blob is at the edge of a cliff-like rollover in the dust disc rather than inside a dark ring. Here we build time-dependent models of TW Hya disc. We find that the classical paradigm cannot account for the morphology of the disc and the blob. We propose that ALMA-discovered blob hides a Neptune mass planet losing gas and dust. We show that radial drift of mm-sized dust particles naturally explains why the blob is located on the edge of the dust disc. Dust particles leaving the planet perform a characteristic U-turn relative to it, producing an azimuthally elongated blob-like emission feature. This scenario also explains why a 10 Myr old disc is so bright in dust continuum. Two scenarios for the dust-losing planet are presented. In the first, a dusty pre-runaway gas envelope of a ∼40 M⊕ Core Accretion planet is disrupted, e.g., as a result of a catastrophic encounter. In the second, a massive dusty pre-collapse gas giant planet formed by Gravitational Instability is disrupted by the energy released in its massive core. Future modelling may discriminate between these scenarios and allow us to study planet formation in an entirely new way – by analysing the flows of dust and gas recently belonging to planets, informing us about the structure of pre-disruption planetary envelopes.
Dust condensation in evolving discs and the composition of planetary building blocks
Authors: Li Min , Huang Shichun , Petaev Michail I , Zhu Zhaohuan , Steffen Jason H
Published: April 2020

Partial condensation of dust from the Solar nebula is likely responsible for the diverse chemical compositions of chondrites and rocky planets/planetesimals in the inner Solar system. We present a forward physical–chemical model of a protoplanetary disc to predict the chemical compositions of planetary building blocks that may form from such a disc. Our model includes the physical evolution of the disc and the condensation, partial advection, and decoupling of the dust within it. The chemical composition of the condensate changes with time and radius. We compare the results of two dust condensation models: one where an element condenses when the mid-plane temperature in the disc is lower than the 50 per cent condensation temperature ($\rm T_{50}$) of that element and the other where the condensation of the dust is calculated by a Gibbs free energy minimization technique assuming chemical equilibrium at local disc temperature and pressure. The results of two models are generally consistent with some systematic differences of ∼10 per cent depending upon the radial distance and an element’s condensation temperature. Both models predict compositions similar to CM, CO, and CV chondrites provided that the decoupling time-scale of the dust is of the order of the evolution time-scale of the disc or longer. If the decoupling time-scale is too short, the composition deviates significantly from the measured values. These models may contribute to our understanding of the chemical compositions of chondrites, and ultimately the terrestrial planets in the Solar system, and may constrain the potential chemical compositions of rocky exoplanets.
The richness-to-mass relation of CAMIRA galaxy clusters from weak-lensing magnification in the Subaru Hyper Suprime-Cam survey
Authors: Chiu I-Non , Umetsu Keiichi , Murata Ryoma , Medezinski Elinor , Oguri Masamune
Published: April 2020

We present a statistical weak-lensing magnification analysis on an optically selected sample of 3029 CAMIRA (Cluster finding Algorithm based on Multiband Identification of Red-sequence gAlaxies) galaxy clusters with richness N > 15 at redshift 0.2 ≤ z < 1.1 in the Subaru Hyper Suprime-Cam survey. We use two distinct populations of colour-selected, flux-limited background galaxies, namely the low-z and high-z samples at mean redshifts of ≈1.1 and ≈1.4, respectively, from which to measure the weak-lensing magnification signal by accounting for cluster contamination as well as masking effects. Our magnification bias measurements are found to be uncontaminated according to validation tests against the ‘null-test’ samples for which the net magnification bias is expected to vanish. The magnification bias for the full CAMIRA sample is detected at a significance level of 9.51σ, which is dominated by the high-z background. We forward-model the observed magnification data to constrain the normalization of the richness-to-mass (N–M) relation for the CAMIRA sample with informative priors on other parameters. The resulting scaling relation is N∝ (M500)0.92 ± 0.13(1 + z)−0.48 ± 0.69, with a characteristic richness of N = 17.72 ± 2.60 and intrinsic lognormal scatter of 0.15 ± 0.07 at M500 = 1014 h−1 M⊙. With the derived N–M relation, we provide magnification-calibrated mass estimates of individual CAMIRA clusters, with the typical uncertainty of ≈39 and ≈32  per cent at richness of ≈20 and ≈40, respectively. We further compare our magnification-inferred N–M relation with those from the shear-based results in the literature, finding good agreement.
A three-dimensional view of Gomez’s hamburger
Authors: Teague Richard , Jankovic Marija R , Haworth Thomas J , Qi Chunhua , Ilee John D
Published: April 2020

Unravelling the three-dimensional physical structure, the temperature and density distribution, of protoplanetary discs is an essential step if we are to confront simulations of embedded planets or dynamical instabilities. In this paper, we focus on submillimeter array observations of the edge-on source, Gomez’s Hamburger, believed to host an overdensity hypothesized to be a product of gravitational instability in the disc, GoHam b. We demonstrate that, by leveraging the well-characterized rotation of a Keplerian disc to deproject observations of molecular lines in position-position-velocity space into disc-centric coordinates, we are able to map out the emission distribution in the $(r,\, z)$ plane and ($x,\, |y|,\, z)$ space. We show that 12CO traces an elevated layer of $z\, /\, r \sim 0.3$, while 13CO traces deeper in the disc at $z\, /\, r \lesssim 0.2$. We identify an azimuthal asymmetry in the deprojected 13CO emission coincident with GoHam b at a polar angle of ≈30○. At the spatial resolution of ∼1.5 arcsec, GoHam b is spatially unresolved, with an upper limit to its radius of <190 au.
The duty cycle of radio galaxies revealed by LOFAR: remnant and restarted radio source populations in the Lockman Hole
Authors: Shabala Stanislav S , Jurlin Nika , Morganti Raffaella , Brienza Marisa , Hardcastle Martin J , Godfrey Leith E H , Krause Martin G H , Turner Ross J
Published: April 2020

Feedback from radio jets associated with active galactic nuclei (AGNs) plays a profound role in the evolution of galaxies. Kinetic power of these radio jets appears to show temporal variation, but the mechanism(s) responsible for this process are not yet clear. Recently, the LOw Frequency ARray (LOFAR) has uncovered large populations of active, remnant, and restarted radio jet populations. By focusing on LOFAR data in the Lockman Hole, in this work we use the Radio AGNs in Semi-Analytic Environments (RAiSE) dynamical model to present the first self-consistent modelling analysis of active, remnant, and restarted radio source populations. Consistent with other recent work, our models predict that remnant radio lobes fade quickly. Any high (>10 per cent) observed fraction of remnant and restarted sources therefore requires a dominant population of short-lived jets. We speculate that this could plausibly be provided by feedback-regulated accretion.
Revealing new features of the millimetre emission of the circumbinary envelope of Mira Ceti
Authors: Hoai D T , Tuan-Anh P , Nhung P T , Darriulat P , Diep P N , Phuong N T , Thai T T
Published: April 2020

We study the morpho-kinematics of the circumbinary envelope of Mira Ceti between ∼100 and ∼350 au from the stars using ALMA observations of the SiO (ν = 0, J= 5−4) and CO (ν = 0, J = 3−2) emissions with the aim of presenting an accurate and reliable picture of what cannot be ignored when modelling the dynamics at stake. A critical study of the uncertainties attached to imaging is presented. The line emissions are shown to be composed of a few separated fragments. They are described in detail and plausible interpretations of their genesis are discussed. Evidence for a focusing effect of the Mira A wind by Mira B over the past century is presented; it accounts for only a small fraction of the overall observed emission but its accumulation over several orbital periods may have produced an enhancement of CO emission in the orbital plane of Mira B. We identify a south-western outflow and give arguments for the anti-correlation observed between CO and SiO emissions being the result of a recent mass ejection accompanied by a shock wave. We discuss the failure of simple scenarios that have been proposed earlier to explain some of the observed features and comment on the apparent lack of continuity between the present observations and those obtained in the close environment of the stars. Evidence is obtained for the presence of large Doppler velocity components near the line of sight aiming to the star, possibly revealing the presence of important turbulence at ∼5–10 au away from Mira A.
Identifying the lens galaxy B 1152+199 as a ghostly damped Lyman α system by the cosmic origins spectrograph
Authors: Dai Xinyu , Bhatiani Saloni , Chen Bin
Published: April 2020

Strong quasar-galaxy lensing provides a powerful tool to probe the interstellar medium (ISM) of the lens galaxy using radiation from the background quasar. Using the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope, we study the cold ISM properties of the lens galaxy in B 1152+199 at a redshift of z = 0.4377. Since existing optical extinction and X-ray absorption measurements of the lens have revealed a large amount of cold ISM, we expected to detect a damped Ly α absorption (DLA) system in the near ultraviolet spectrum; however, our upper limit on the H i column density is several orders of magnitude below the expectation. We also marginally detect O i and C ii absorption lines associated with the lens galaxy in the COS spectrum. Thus, the lens galaxy is identified as a ghostly DLA system, and further investigations of these ghostly DLA systems would be important to characterize the biases of using DLAs to probe the matter density of the universe. Although preliminary, the most likely explanation of the non-detection of the DLA is because of the Ly α emission of the lens galaxy that fills in the absorption trough, with a Ly α luminosity of $4\times 10^{42}\, \hbox{erg~s$^{-1}$}$.
Multiwavelength observations of PSR J2032+4127 during the 2017 periastron passage
Authors: Chernyakova M , Malyshev D , Blay P , van Soelen B , Tsygankov S
Published: April 2020

PSR J2032+4127 is only the second known gamma-ray binary where it is confirmed that a young radio pulsar is in orbit around a Be-star. The interaction of the pulsar wind with the mass outflow from the companion leads to broad-band emission from radio up to TeV energies. In this paper we present results of optical monitoring of the 2017 periastron passage with the Nordic Optical Telescope. These observations are complemented by X-ray (Swift/XRT, NuSTAR) and GeV (Fermi/LAT) monitoring. Joint analysis of the evolution of the parameters of the H α line and the broad-band (X-ray to TeV) spectral shape allows us to propose a model linking the observed emission to the interaction of the pulsar and Be-star winds under the assumption of the inclined disc geometry. Our model allows the observed flux and spectral evolution of the system to be explained in a self-consistent way.
The excitation temperature of the CH 3335-MHz line
Authors: Dailey Erin M , Smith Allison J , Magnani Loris , Andersson B-G , Reach William T
Published: April 2020

Molecular hydrogen is the main constituent of dense molecular clouds, but is expected to also be a dominant constituent in many environments where CO can no longer be seen, the so-called ‘CO-dark molecular gas’. Based on comparisons of ultraviolet spectroscopy of H2 and optical line observations (4300 Å), CH is a prime candidate to trace H2. Since the optical line (and the UV lines at 3143, 3890, and 3878 Å) require bright background sources (and the CH N = 2←1 ground state rotation line at 149 µm requires space-based, or stratospheric, observations), the hyperfine structure transition at 3335 MHz is a potentially important tool for probing the CO-dark molecular gas. However, the excitation of this transition is complicated, and has often been found to be inverted, making column density determinations uncertain. To clarify the potential use of the 3.3-GHz line as a proxy for H2, we have observed the CH 3335-MHz line with the Arecibo 305-m radio telescope along 16 lines of sight towards stars with existing measurements of the 4300-Å line. By comparing the CH column densities from optical and UV absorption lines to the CH radio emission line, we can derive the excitation temperature (Tex) of the 3335-MHz transition. We obtain a wide range of excitation temperatures for nine lines of sight, including some with |Tex| < 5 K. The common assumption that Tex for the 3335-MHz line is always much larger than the background temperature (Tbg) is not always warranted and can lead to significant errors in the value of N(CH).
Study of flux-rope characteristics at sub-astronomical-unit distances using the Helios 1 and 2 spacecraft
Authors: Raghav Anil , Gaikwad Sandesh , Wang Yuming , Shaikh Zubair I , Mishra Wageesh , Zao Ake
Published: April 2020

Magnetic flux ropes observed as magnetic clouds near 1 au have been extensively studied in the literature and their distinct features are derived using numerous models. These studies summarize the general characteristics of flux ropes at 1 au without providing an understanding of the continuous evolution of the flux ropes from near the Sun to 1 au. In the present study, we investigate 26 flux ropes observed by the Helios 1 and 2 spacecraft (from 0.3 to 1 au) using the velocity-modified Gold–Hoyle model. The correlation and regression analyses suggest that the expansion speed, poloidal speed, total magnetic helicity and twist per au of the flux rope are independent of heliospheric distance. The study implies that the aforementioned features are more strongly influenced by their internal properties compared with external conditions in the ambient medium. Moreover, the poloidal magnetic flux and magnetic energy of the studied flux ropes exhibit power-law dependence on heliospheric distance. A better understanding of the underlying physics and corroboration of these results is expected from the Parker Solar Probe measurements in the near future.
HIR4: cosmology from a simulated neutral hydrogen full sky using Horizon Run 4
Authors: Asorey Jacobo , Parkinson David , Shi Feng , Song Yong-Seon , Ahn Kyungjin , Kim Juhan , Yao Jian , Zhang Le , Zuo Shifan
Published: April 2020

The distribution of cosmological neutral hydrogen will provide a new window into the large-scale structure of the Universe with the next generation of radio telescopes and surveys. The observation of this material, through 21 cm line emission, will be confused by foreground emission in the same frequencies. Even after these foregrounds are removed, the reconstructed map may not exactly match the original cosmological signal, which will introduce systematic errors and offset into the measured correlations. In this paper, we simulate future surveys of neutral hydrogen using the Horizon Run 4 (HR4) cosmological N-body simulation. We generate H i intensity maps from the HR4 halo catalogue, and combine with foreground radio emission maps from the Global Sky Model, to create accurate simulations over the entire sky. We simulate the H i sky for the frequency range 700–800 MHz, matching the sensitivity of the Tianlai pathfinder. We test the accuracy of the fastICA, PCA, and log-polynomial fitting foreground removal methods to recover the input cosmological angular power spectrum and measure the parameters. We show the effect of survey noise levels and beam sizes on the recovered the cosmological constraints. We find that while the reconstruction removes power from the cosmological 21 cm distribution on large scales, we can correct for this and recover the input parameters in the noise-free case. However, the effect of noise and beam size of the Tianlai pathfinder prevents accurate recovery of the cosmological parameters when using only intensity mapping information.
Prefoldins contribute to maintaining the levels of the spliceosome LSM2–8 complex through Hsp90 in Arabidopsis
Authors: Esteve-Bruna David , Carrasco-López Cristian , Blanco-Touriñán Noel , Iserte Javier , Calleja-Cabrera Julián , Perea-Resa Carlos , Úrbez Cristina , Carrasco Pedro , Yanovsky Marcelo J , Blázquez Miguel A , Salinas Julio , Alabadí David
Published: April 2020

Although originally identified as the components of the complex aiding the cytosolic chaperonin CCT in the folding of actins and tubulins in the cytosol, prefoldins (PFDs) are emerging as novel regulators influencing gene expression in the nucleus. Work conducted mainly in yeast and animals showed that PFDs act as transcriptional regulators and participate in the nuclear proteostasis. To investigate new functions of PFDs, we performed a co-expression analysis in Arabidopsis thaliana. Results revealed co-expression between PFD and the Sm-like (LSM) genes, which encode the LSM2–8 spliceosome core complex, in this model organism. Here, we show that PFDs interact with and are required to maintain adequate levels of the LSM2–8 complex. Our data indicate that levels of the LSM8 protein, which defines and confers the functional specificity of the complex, are reduced in pfd mutants and in response to the Hsp90 inhibitor geldanamycin. We provide biochemical evidence showing that LSM8 is a client of Hsp90 and that PFD4 mediates the interaction between both proteins. Consistent with our results and with the role of the LSM2–8 complex in splicing through the stabilization of the U6 snRNA, pfd mutants showed reduced levels of this snRNA and altered pre-mRNA splicing patterns.
Combined Unilateral Subthalamic Nucleus and Contralateral Globus Pallidus Interna Deep Brain Stimulation for Treatment of Parkinson Disease: A Pilot Study of Symptom-Tailored Stimulation
Authors: Zhang Chencheng , Wang Linbin , Hu Wei , Wang Tao , Zhao Yijie , Pan Yixin , Almeida Leonardo , Ramirez-Zamora Adolfo , Sun Bomin , Li Dianyou
Published: April 2020

BACKGROUND

Subthalamic nucleus (STN) and globus pallidus interna (GPi) are the most effective targets in deep brain stimulation (DBS) treatment for Parkinson disease (PD). However, the individualized selection of targets remains a clinical challenge.

OBJECTIVE

To combine unilateral STN and contralateral GPi stimulation (STN DBS in one brain hemisphere and GPi DBS in the other) to maximize the clinical advantages of each target while inducing fewer adverse side effects in selected patients with PD because each target has its own clinical effects and risk profiles.

METHODS

We reviewed the clinical outcomes of 8 patients with idiopathic PD treated with combined unilateral STN and contralateral GPi DBS. Clinical outcome assessments, focusing on motor and nonmotor symptoms, were performed at baseline and 6-mo and 12-mo follow-up. We performed the assessments under the following conditions: medication on and off (bilateral stimulation on and off and unilateral STN stimulation on).

RESULTS

Patients showed a significant improvement in motor symptoms, as assessed by the Unified Parkinson Disease Rating Scale III (UPDRS-III) and Timed Up-and-Go Test (TUG), in the off-medication/on-stimulation state at 6-mo and 12-mo follow-up. Also, patients reported a better quality of life, and their intake of levodopa was reduced at 12-mo follow-up. In the on-medication condition, bilateral stimulation was associated with an improvement in axial symptoms, with a 64% improvement in measures of gait and falls at 12-mo follow-up. No irreversible adverse side effects were observed.

CONCLUSION

Our findings suggest that combined unilateral STN and contralateral GPi DBS could offer an effective and well-tolerated DBS treatment for certain PD patients.
Hydroxychloroquine and short-course radiotherapy in elderly patients with newly diagnosed high-grade glioma: a randomized phase II trial
Authors: Brazil Lucy , Swampillai Angela L , Mak Ka Man , Edwards Darren , Mesiri Pavlina , Clifton-Hadley Laura , Shaffer Richard , Lewis Joanne , Watts Colin , Jeffries Sarah , Gkogkou Pinelopi , Chalmers Anthony J , Fersht Naomi L , Hackshaw Allan , Short Susan C
Published: April 2020

Background

Effective treatment for patients at least 70 years with newly diagnosed glioblastoma remains challenging and alternatives to conventional cytotoxics are appealing. Autophagy inhibition has shown promising efficacy and safety in small studies of glioblastoma and other cancers.

Methods

We conducted a randomized phase II trial to compare radiotherapy with or without hydroxychloroquine (2:1 allocation). Patients aged at least 70 years with newly diagnosed high-grade glioma deemed suitable for short-course radiotherapy with an ECOG performance status of 0–1 were included. Radiotherapy treatment consisted of 30 Gy, delivered as 6 fractions given over 2 weeks (5 Gy per fraction). Hydroxychloroquine was given as 200 mg orally b.d. from 7 days prior to radiotherapy until disease progression. The primary endpoint was 1-year overall survival (OS). Secondary endpoints included progression-free survival (PFS), quality of life, and toxicity.

Results

Fifty-four patients with a median age of 75 were randomized between May 2013 and October 2016. The trial was stopped early in 2016. One-year OS was 20.3% (95% confidence interval [CI] 8.2–36.0) hydroxychloroquine group, and 41.2% (95% CI 18.6–62.6) radiotherapy alone, with a median survival of 7.9 and 11.5 months, respectively. The corresponding 6-month PFS was 35.3% (95% CI 19.3–51.7) and 29.4% (95% CI 10.7–51.1). The outcome in the control arm was better than expected and the excess of deaths in the hydroxychloroquine group appeared unrelated to cancer. There were more grade 3–5 events in the hydroxychloroquine group (60.0%) versus radiotherapy alone (38.9%) without any clear common causation.

Conclusions

Hydroxychloroquine with short-course radiotherapy did not improve survival compared to radiotherapy alone in elderly patients with glioblastoma.