bluuebunny/crossref_metadata_2025_split huggingface dataset:
High linear energy transfer carbon-ion irradiation upregulates PD-L1 expression more significantly than X-rays in human osteosarcoma U2OS cells
Authors: Permata Tiara Bunga Mayang , Sato Hiro , Gu Wenchao , Kakoti Sangeeta , Uchihara Yuki , Yoshimatsu Yukihiko , Sato Itaru , Kato Reona , Yamauchi Motohiro , Suzuki Keiji , Oike Takahiro , Tsushima Yoshito , Gondhowiardjo Soehartati , Ohno Tatsuya , Yasuhara Takaaki , Shibata Atsushi 
Published: May 2021

Abstract
Programmed death ligand 1 (PD-L1) expression on the surface of cancer cells affects the efficacy of anti-PD-1/PD-L1 immune checkpoint therapy. However, the mechanism underlying PD-L1 expression in cancer cells is not fully understood, particularly after ionizing radiation (IR). Here, we examined the impact of high linear energy transfer (LET) carbon-ion irradiation on the expression of PD-L1 in human osteosarcoma U2OS cells. We found that the upregulation of PD-L1 expression after high LET carbon-ion irradiation was greater than that induced by X-rays at the same physical and relative biological effectiveness (RBE) dose, and that the upregulation of PD-L1 induced by high LET carbon-ion irradiation was predominantly dependent on ataxia telangiectasia and Rad3-related (ATR) kinase activity. Moreover, we showed that the downstream signaling, e.g. STAT1 phosphorylation and IRF1 expression, was upregulated to a greater extent after high LET carbon-ion irradiation than X-rays, and that IRF1 upregulation was also ATR dependent. Finally, to visualize PD-L1 molecules on the cell surface in 3D, we applied immunofluorescence-based super-resolution imaging. The three-dimensional structured illumination microscopy (3D-SIM) analyses revealed substantial increases in the number of presented PD-L1 molecules on the cell surface after high LET carbon-ion irradiation compared with X-ray irradiation.
Putting collation of text witnesses on a formal basis
Authors: Dähne Janis , Pöckelmann Marcus , Ritter Jörg , Molitor Paul 
Published: May 2021

Abstract
This article presents an approach to the collation problem of text witnesses which is correct for all distance functions and is applicable to the alignment of any types of tokens, be it letters, words, sentences, or paragraphs. In contrast to the existing approaches, which all are heuristics in nature, we specify a formal model in the form of an integer linear program (ILP) that formally describes the optimization problem. For a special case that usually occurs in practice, we then transfer the ILP into an efficient algorithm that optimally solves the alignment problem. In the second part of the article, we apply our approach to the alignment of paragraphs of text witnesses—an alignment problem that has received little attention in the literature so far—and compare the results of our approach, which we have called TSaligner, with those of CollateX.
Uncertain times: the redshift–time relation from cosmology and stars
Authors: Boylan-Kolchin Michael , Weisz Daniel R 
Published: May 2021

ABSTRACT
Planck data provide precise constraints on cosmological parameters when assuming the base ΛCDM model, including a 0.17 per cent measurement of the age of the Universe, $t_0=13.797 \pm 0.023\, {\rm Gyr}$. However, the persistence of the ‘Hubble tension’ calls the base ΛCDM model’s completeness into question and has spurred interest in models such as early dark energy (EDE) that modify the assumed expansion history of the Universe. We investigate the effect of EDE on the redshift–time relation z↔t and find that it differs from the base ΛCDM model by at least ${\approx } 4{{\ \rm per\ cent}}$ at all t and z. As long as EDE remains observationally viable, any inferred t ← z or z ← t quoted to a higher level of precision do not reflect the current status of our understanding of cosmology. This uncertainty has important astrophysical implications: the reionization epoch – 10 &gt; z &gt; 6 – corresponds to disjoint lookback time periods in the base ΛCDM and EDE models, and the EDE value of t0 = 13.25 ± 0.17 Gyr is in tension with published ages of some stars, star clusters, and ultrafaint dwarf galaxies. However, most published stellar ages do not include an uncertainty in accuracy (due to, e.g. uncertain distances and stellar physics) that is estimated to be $\sim 7\!-\!10{{\ \rm per\ cent}}$, potentially reconciling stellar ages with $t_{0,\rm EDE}$. We discuss how the big data era for stars is providing extremely precise ages ($\lt 1{{\ \rm per\ cent}}$) and how improved distances and treatment of stellar physics such as convection could result in ages accurate to $4\!-\!5{{\ \rm per\ cent}}$, comparable to the current accuracy of t↔z. Such precise and accurate stellar ages can provide detailed insight into the high-redshift Universe independent of a cosmological model.
A new look at old friends – I. Imaging classical radio galaxies with uGMRT and MeerKAT
Authors: Fanaroff Bernie , Lal Dharam V , Venturi Tiziana , Smirnov Oleg M , Bondi Marco , Thorat Kshitij , Bester Landman H , Józsa Gyula I G , Kleiner Dane , Loi Francesca , Makhathini Sphesihle , White Sarah V 
Published: May 2021

ABSTRACT
We have undertaken a systematic study of FR I and FR II radio galaxies with the upgraded Giant Metrewave Radio Telescope (uGMRT) and MeerKAT. The main goal is to explore whether the unprecedented few μJy sensitivity reached in the range 550–1712 MHz at the resolution of ∼4–7 arcsec reveals new features in the radio emission which might need us to revise our current classification scheme for classical radio galaxies. In this paper, we present the results for the first set of four radio galaxies, i.e. 4C 12.02, 4C 12.03, CGCG 044–046, and CGCG 021–063. The sources have been selected from the 4C sample with well-defined criteria and have been imaged with the uGMRT in the range 550–850 MHz (band 4) and with the MeerKAT in the range 856–1712 MHz (L-band). Full resolution images are presented for all sources in the sample, together with MeerKAT in-band spectral images. Additionally, the uGMRT–MeerKAT spectral image and MeerKAT L-band polarization structure are provided for CGCG 044–046. Our images contain a wealth of morphological details, such as filamentary structure in the emission from the lobes, radio emission beyond the hotspots in three sources, and misalignments. We briefly discuss the overall properties of CGCG 044–046 in the light of the local environment as well, and show possible restarted activity in 4C 12.03 which needs to be confirmed. We conclude that at least for the sources presented here, the classical FR I/FR II morphological classification still holds with the current improved imaging capabilities, but the richness in details also suggests caution in the systematic morphological classification carried out with automatic procedures in surveys with poorer sensitivity and angular resolution.
An analysis of the time-frequency structure of several bursts from FRB 121102 detected with MeerKAT
Authors: Platts E , Caleb M , Stappers B W , Main R A , Weltman A , Shock J P , Kramer M , Bezuidenhout M C , Jankowski F , Morello V , Possenti A , Rajwade K M , Rhodes L , Wu J 
Published: May 2021

ABSTRACT
We present a detailed study of the complex time-frequency structure of a sample of previously reported bursts of FRB 121102 detected with the MeerKAT telescope in September 2019. The wide contiguous bandwidth of these observations have revealed a complex bifurcating structure in some bursts at 1250 MHz. When de-dispersed to their structure-optimized dispersion measures (DMs), two of the bursts show a clear deviation from the cold plasma dispersion relationship below 1250 MHz. We find a differential DM of ${\sim }1{-}2~{\rm pc \, cm^{-3}}$ between the lower and higher frequency regions of each burst. We investigate the possibility of plasma lensing by Gaussian lenses of ∼10 au in the host galaxy, and demonstrate that they can qualitatively produce some of the observed burst morphologies. Other possible causes for the observed frequency dependence, such as Faraday delay, are also discussed. Unresolved sub-components in the bursts, however, may have led to an incorrect DM determination. We hence advise exercising caution when considering bursts in isolation. We analyse the presence of two apparent burst pairs. One of these pairs is a potential example of upward frequency drift. The possibility that burst pairs are echoes is also discussed. The average structure-optimized DM is found to be $563.5\pm 0.2 (\text{sys}) \pm 0.8 (\text{stat})\, {\rm pc \, cm^{-3}}$ – consistent with the values reported in 2018. We use two independent methods to determine the structure-optimized DM of the bursts: the DM_phase algorithm and autocorrelation functions. The latter – originally developed for pulsar analysis – is applied to fast radio bursts for the first time in this paper.
Discovery of a young low-mass brown dwarf transiting a fast-rotating F-type star by the Galactic Plane eXoplanet (GPX) survey
Authors: Benni P , Burdanov A Y , Krushinsky V V , Bonfanti A , Hébrard G , Almenara J M , Dalal S , Demangeon O D S , Tsantaki M , Pepper J , Stassun K G , Vanderburg A , Belinski A , Kashaev F , Barkaoui K , Kim T , Kang W , Antonyuk K , Dyachenko V V , Rastegaev D A , Beskakotov A , Mitrofanova A A , Pozuelos F J , Kuznetsov E D , Popov A , Kiefer F , Wilson P A , Ricker G , Vanderspek R , Latham D W , Seager S , Jenkins J M , Sokov E , Sokova I , Marchini A , Papini R , Salvaggio F , Banfi M , Baştürk Ö , Torun Ş , Yalçınkaya S , Ivanov K , Valyavin G , Jehin E , Gillon M , Pakštienė E , Hentunen V-P , Shadick S , Bretton M , Wünsche A , Garlitz J , Jongen Y , Molina D , Girardin E , Grau Horta F , Naves R , Benkhaldoun Z , Joner M D , Spencer M , Bieryla A , Stevens D J , Jensen E L N , Collins K A , Charbonneau D , Quintana E V , Mullally S E , Henze C E 
Published: May 2021

ABSTRACT
We announce the discovery of GPX-1 b, a transiting brown dwarf with a mass of 19.7 ± 1.6 MJup and a radius of 1.47 ± 0.10 RJup, the first substellar object discovered by the Galactic Plane eXoplanet (GPX) survey. The brown dwarf transits a moderately bright (V = 12.3 mag) fast-rotating F-type star with a projected rotational velocity $v\sin {\, i_*}=40\pm 10$ km s−1. We use the isochrone placement algorithm to characterize the host star, which has effective temperature 7000 ± 200 K, mass 1.68 ± 0.10 $\mathrm{\it M}_\odot$, radius 1.56 ± 0.10 $\mathrm{\it R}_\odot$, and approximate age $0.27_{-0.15}^{+0.09}$ Gyr. GPX-1 b has an orbital period of ∼1.75 d and a transit depth of 0.90 ± 0.03  per cent. We describe the GPX transit detection observations, subsequent photometric and speckle-interferometric follow-up observations, and SOPHIE spectroscopic measurements, which allowed us to establish the presence of a substellar object around the host star. GPX-1 was observed at 30-min integrations by TESS in Sector 18, but the data are affected by blending with a 3.4 mag brighter star 42 arcsec away. GPX-1 b is one of about two dozen transiting brown dwarfs known to date, with a mass close to the theoretical brown dwarf/gas giant planet mass transition boundary. Since GPX-1 is a moderately bright and fast-rotating star, it can be followed-up by the means of the Doppler tomography.
An H α/X-ray orphan cloud as a signpost of intracluster medium clumping
Authors: Ge Chong , Luo Rongxin , Sun Ming , Yagi Masafumi , Jáchym Pavel , Boselli Alessandro , Fossati Matteo , Nulsen Paul E J , Sarazin Craig , Edge Tim , Gavazzi Giuseppe , Gaspari Massimo , Koda Jin , Komiyama Yutaka , Yoshida Michitoshi 
Published: May 2021

ABSTRACT
Recent studies have highlighted the potential significance of intracluster medium (ICM) clumping and its important implications for cluster cosmology and baryon physics. Many of the ICM clumps can originate from infalling galaxies, as stripped interstellar medium (ISM) mixing into the hot ICM. However, a direct connection between ICM clumping and stripped ISM has not been unambiguously established before. Here, we present the discovery of the first and still the only known isolated cloud (or orphan cloud [OC]) detected in both X-rays and H α in the nearby cluster A1367. With an effective radius of 30 kpc, this cloud has an average X-ray temperature of 1.6 keV, a bolometric X-ray luminosity of ∼3.1 × 1041 erg s−1, and a hot gas mass of ∼1010 M⊙. From the Multi-Unit Spectroscopic Explorer (MUSE) data, the OC shows an interesting velocity gradient nearly along the east-west direction with a low level of velocity dispersion of ∼80 km s−1, which may suggest a low level of the ICM turbulence. The emission line diagnostics suggest little star formation in the main H α cloud and a low-ionization (nuclear) emission-line regions like spectrum, but the excitation mechanisms remain unclear. This example shows that stripped ISM, even long after the initial removal from the galaxy, can still induce ICM inhomogeneities. We suggest that the magnetic field can stabilize the OC by suppressing hydrodynamic instabilities and thermal conduction. This example also suggests that at least some ICM clumps are multiphase in nature and implies that the ICM clumps can also be traced in H α. Thus, future deep and wide-field H α surveys can be used to probe the ICM clumping and turbulence.
A search for pulsar companions around low-mass white dwarfs
Authors: Athanasiadis Tilemachos M , Berezina Marina , Antoniadis John , Champion David J , Cruces Marilyn , Spitler Laura , Kramer Michael 
Published: May 2021

ABSTRACT
We report on a search for pulsars at the positions of eight low-mass white dwarfs and one higher mass white dwarf with the 100-m Effelsberg Radio Telescope. These systems have orbital parameters suggesting that their unseen companions are either massive white dwarfs or neutron stars (NSs). Our observations were performed at 1.36 GHz, reaching sensitivities of 0.1–0.2 mJy. We searched our data accounting for the possible acceleration and jerk of the pulsar signals due to orbital motion, but found no significant pulsar signals. Considering our result jointly with 20 non-detections of similar systems with the Greenbank Radio Telescope, we infer fNS ≤ 0.10, for the fraction of NSs orbiting these white dwarfs. We discuss the sensitivity of this result to the underlying assumptions and conclude with a brief discussion on the prospects of targeted surveys for discovering millisecond pulsars.
Kinetics of heterochiral strand displacement from PNA–DNA heteroduplexes
Authors: Kundu Nandini , Young Brian E , Sczepanski Jonathan T 
Published: May 2021

AbstractDynamic DNA nanodevices represent powerful tools for the interrogation and manipulation of biological systems. Yet, implementation remains challenging due to nuclease degradation and other cellular factors. Use of l-DNA, the nuclease resistant enantiomer of native d-DNA, provides a promising solution. On this basis, we recently developed a strand displacement methodology, referred to as ‘heterochiral’ strand displacement, that enables robust l-DNA nanodevices to be sequence-specifically interfaced with endogenous d-nucleic acids. However, the underlying reaction – strand displacement from PNA–DNA heteroduplexes – remains poorly characterized, limiting design capabilities. Herein, we characterize the kinetics of strand displacement from PNA–DNA heteroduplexes and show that reaction rates can be predictably tuned based on several common design parameters, including toehold length and mismatches. Moreover, we investigate the impact of nucleic acid stereochemistry on reaction kinetics and thermodynamics, revealing important insights into the biophysical mechanisms of heterochiral strand displacement. Importantly, we show that strand displacement from PNA–DNA heteroduplexes is compatible with RNA inputs, the most common nucleic acid target for intracellular applications. Overall, this work greatly improves the understanding of heterochiral strand displacement reactions and will be useful in the rational design and optimization of l-DNA nanodevices that operate at the interface with biology.
G-quadruplex binders as cytostatic modulators of innate immune genes in cancer cells
Authors: Miglietta Giulia , Russo Marco , Duardo Renée C , Capranico Giovanni 
Published: May 2021

Abstract
G-quadruplexes (G4s) are non-canonical nucleic acid structures involved in fundamental biological processes. As G4s are promising anticancer targets, in past decades the search for effective anticancer G4 binders aimed at the discovery of more cytotoxic ligands interfering with specific G4 structures at oncogenes or telomeres. Here, we have instead observed a significant activation of innate immune genes by two unrelated ligands at non-cytotoxic concentrations. The studied G4 binders (pyridostatin and PhenDC3) can induce an increase of micronuclei triggering the activation of the cytoplasmic STING (stimulator of interferon response cGAMP interactor 1) signaling pathway in human and murine cancer cells. Ligand activity can then lead to type I interferon production and innate immune gene activation. Moreover, specific gene expression patterns mediated by a G4 binder in cancer cells correlate with immunological hot features and better survival in human TCGA (The Cancer Genome Atlas) breast tumors. The findings open to the development of cytostatic G4 binders as effective immunomodulators for combination immunotherapies in unresponsive tumors.
High-performance polarization-sensitive photodetectors on two-dimensional β-InSe
Authors: Guo Zhinan , Cao Rui , Wang Huide , Zhang Xi , Meng Fanxu , Chen Xue , Gao Siyan , Sang David K , Nguyen Thi Huong , Duong Anh Tuan , Zhao Jinlai , Zeng Yu-Jia , Cho Sunglae , Zhao Bing , Tan Ping-Heng , Zhang Han , Fan Dianyuan 
Published: May 2021

Abstract
Two-dimensional (2D) indium selenide (InSe) has been widely studied for application in transistors and photodetectors, which benefit from its excellent optoelectronic properties. Among the three specific polytypes (γ-, ϵ- and β-phase) of InSe, only the crystal lattice of InSe in β-phase (β-InSe) belongs to a non-symmetry point group of $D_{6h}^4$, which indicates stronger anisotropic transport behavior and potential in the polarized photodetection of β-InSe-based optoelectronic devices. Therefore, we prepare the stable p-type 2D-layered β-InSe via temperature gradient method. The anisotropic Raman, transport and photoresponse properties of β-InSe have been experimentally and theoretically proven, showing that the β-InSe-based device has a ratio of 3.76 for the maximum to minimum dark current at two orthogonal orientations and a high photocurrent anisotropic ratio of 0.70 at 1 V bias voltage, respectively. The appealing anisotropic properties demonstrated in this work clearly identify β-InSe as a competitive candidate for filter-free polarization-sensitive photodetectors.
Longer-Term Impact of the Flavored Tobacco Restriction in Two Massachusetts Communities: A Mixed-Methods Study
Authors: Kingsley Melody , Setodji Claude M , Pane Joseph D , Shadel William G , Song Glory , Robertson Jennifer , Kephart Lindsay , Zepeda Samantha , Henley Patricia , Ursprung W W Sanouri 
Published: May 2021

Abstract

Introduction
In response to high rates of youth tobacco use, many states and localities are considering regulations on flavored tobacco products. The purpose of this study was to assess whether flavored tobacco restrictions (FTRs) in Massachusetts curb youth tobacco use over time and whether a dose–response effect of length of policy implementation on tobacco-related outcomes exists.

Aims and Methods
Using a quasiexperimental design, two municipalities with a FTR (adopting municipalities) were matched to a comparison municipality without a FTR. Surveys were administered before (December 2015) and after (January and February 2018) policy implementation to high school students in these municipalities (more than 2000 surveys completed at both timepoints). At follow-up, adopting municipalities had a policy in place for 1 and 2 years, respectively. In 2019, focus groups were conducted with high school students in each municipality.

Results
Increases seen in current tobacco use from baseline to follow-up were significantly smaller in adopting municipalities compared to the comparison (−9.4% [−14.2%, −4.6%] and −6.3% [−10.8%, −1.8%], respectively). However, policy impact was greater in one adopting municipality despite shorter length of implementation. Focus groups indicated reasons for differential impact, including proximity to localities without FTRs.

Conclusions
Restrictions implemented in adopting municipalities had positive impacts on youth tobacco awareness and use 1–2 years postimplementation. Policy impact varies depending on remaining points of access to flavored tobacco, as such policy effectiveness may increase as more localities restrict these products.

Implications
In response to high rates of youth flavored tobacco use (including flavored vape products), federal, state, and localities have passed FTRs that reduce availability of flavored tobacco in youth-accessible stores. Previous research has found that FTRs may curb youth tobacco use in the short-term; however, the long-term effectiveness remains unknown.
This is the first study to show FTRs can curb youth tobacco use and reduce youth awareness of tobacco prices and brands even 2 years after policy passage. Municipality-specific factors, including proximity to localities without FTRs, may attenuate policy impact, highlighting the importance of widespread policy adoption.