bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulating Gas Inflow at the Disk–Halo Interface
Authors: Melso Nicole , Bryan Greg L. , Li 李 Miao 邈 
Published: February 2019

Abstract
The interaction between inflowing gas clouds and galactic outflows at the interface where the galactic disk transitions into the circumgalactic medium is an important process in galaxy fueling, yet it remains poorly understood. Using a series of tall-box hydrodynamic Enzo simulations, we have studied the interaction between smooth gas inflow and supernovae-driven outflow at the disk–halo interface with parsec-scale resolution. A realistic wind of outflowing material is generated by supernova explosions in the disk, while inflowing gas is injected at the top boundary of the simulation box with an injection velocity ranging from 10 to 100 km s−1. We find that cooling and hydrodynamic instabilities drive the injected gas to fragment into cold (∼103 K) cloud clumps with typical densities of ∼1 cm−3. These clumps initially accelerate before interacting and partially mixing with the outflow and decelerating to velocities in the 50–100 km s−1 range. When the gas clumps hit the disk, 10%–50% of the injected material is able to accrete depending on the injection velocity. Clumps originating from gas injected with a higher initial velocity approach the disk with greater ram pressure, allowing them to penetrate through the disk in low-density regions. We use (equilibrium) Cloudy photoionization models to generate absorption and emission signatures of gas accretion, finding that our mock H i and Hα observables are prominent and generally consistent with measurements in the Milky Way. We do not predict enhanced emission/absorption for higher ionization states such as O vi.
Spatially Resolved X-Ray Spectroscopy of Kepler’s Supernova Remnant: Distinct Properties of the Circumstellar Medium and the Ejecta
Authors: Sun 孫 Lei 磊 , Chen 陳 Yang 陽 
Published: February 2019

Abstract

Kepler’s supernova remnant (SNR) is believed to result from a Type Ia supernova, but to be interacting with dense circumstellar material (CSM), which makes its progenitor system a mystery. Using the Chandra ACIS-S 741 ks effective exposure data and an advanced adaptive binning algorithm, we analyze the spectra from tessellated regions in Kepler’s SNR. For the first time, we map out the detailed spatial distributions of emission measure (EM), electron temperature, ionization parameter, and metal abundances for both the low- and high-temperature plasma components. The low-temperature plasma diverges into two branches in the temperature versus ionization parameter diagram, which appear to be spatially associated with the warm CSM dusts and the Si- and S-rich ejecta, respectively. We construct the probability distribution functions of abundance ratios of O and Mg to L-shell emitting Fe ([O]/[Fe]L and [Mg]/[Fe]L), and fit them with double Gaussians. Thereby, we distinguish the CSM from the ejecta: the CSM is characterized by

and

, while the ejecta by

and

. We estimate the total hydrogen mass of the shocked CSM as ∼1.4 M
⊙ and the EM-weighted mean [Mg]/[O] = 1.14 ± 0.49, which can be reproduced with an asymptotic giant branch donor star with initial mass of ∼4 M
⊙. The abundance ratios from the shocked ejecta are well compatible with the predicted results from spherical delayed-detonation models for Type Ia supernovae. We also find that the two “ears” of the remnant are dominated by Si- and S-rich ejecta, thus favoring a pre-explosion jets scenario.
Elliptical Galaxy in the Making: The Dual Active Galactic Nuclei and Metal-enriched Halo of Mrk 273
Authors: Liu Weizhe , Veilleux Sylvain , Iwasawa Kazushi , Rupke David S. N. , Teng Stacy , U Vivian , Tombesi Francesco , Sanders David , Max Claire E. , Meléndez Marcio 
Published: February 2019

Abstract
A systematic analysis of the X-ray emission from the nearby ultraluminous infrared galaxy Mrk 273 was carried out by combining new 200 ks Chandra data with archived 44 ks data. The active galactic nucleus (AGN) associated with the southwest nucleus is confirmed by the new data, and a secondary hard X-ray (4–8 keV) point source is detected, coincident with the northeast nucleus at a projected distance of 0.75 kpc from the southwest nucleus. The hard X-ray spectrum of the northeast nucleus is consistent with a heavily absorbed AGN, making Mrk 273 another example of a dual AGN in a nearby galaxy merger. Significant 1–3 keV emission is found along the ionization cones and outflowing gas detected in a previous study. The data also map the giant X-ray nebula south of the host galaxy with unprecedented detail. This nebula extends on a scale of ∼40 kpc × 40 kpc and is not closely related to the well-known tidal tail seen in the optical. The X-ray emission of the nebula is best described by a single-temperature gas model, with a temperature of ∼7 million K and a supersolar α/Fe ratio. Further analysis suggests that the southern nebula has most likely been heated and enriched by multiple galactic outflows generated by the AGN and/or circumnuclear starburst in the past, on a timescale of ≲0.1 Gyr, similar to the merger event itself.
Laboratory Photochemistry of Covalently Bonded Fluorene Clusters: Observation of an Interesting PAH Bowl-forming Mechanism
Authors: Zhang Weiwei , Si Yubing , Zhen Junfeng , Chen Tao , Linnartz Harold , Tielens Alexander G. G. M. 
Published: February 2019

Abstract
The fullerene C60, one of the largest molecules identified in the interstellar medium (ISM), has been proposed to form top-down through the photochemical processing of large (more than 60 C atoms) polycyclic aromatic hydrocarbon (PAH) molecules. In this article, we focus on the opposite process, investigating the possibility that fullerenes form from small PAHs, in which bowl-forming plays a central role. We combine laboratory experiments and quantum chemical calculations to study the formation of larger PAHs from charged fluorene clusters. The experiments show that with visible laser irradiation, the fluorene dimer cation—[C13H9−C13H9]+—and the fluorene trimer cation—[C13H9−C13H8−C13H9]+—undergo photodehydrogenation and photoisomerization, resulting in bowl-structured aromatic cluster ions, C26H12
+ and C39H20
+, respectively. To study the details of this chemical process, we employ quantum chemistry that allows us to determine the structures of the newly formed cluster ions, to calculate the dissociation energies for hydrogen loss, and to derive the underlying reaction pathways. These results demonstrate that smaller PAH clusters (with less than 60 C atoms) can convert to larger bowled geometries that might act as building blocks for fullerenes, because the bowl-forming mechanism greatly facilitates the conversion from dehydrogenated PAHs to cages. Moreover, the bowl-forming induces a permanent dipole moment that—in principle—allows one to search for such species using radio astronomy.
Elevated Expression of Macrophage Migration Inhibitory Factor Promotes Inflammatory Bone Resorption Induced in a Mouse Model of Periradicular Periodontitis
Authors: Howait Mohammed , Albassam Abdullah , Yamada Chiaki , Sasaki Hajime , Bahammam Laila , Azuma Mariane Maffei , Cintra Luciano Tavares Angelo , Satoskar Abhay R. , Yamada Satoru , White Robert , Kawai Toshihisa , Movila Alexandru 
Published: February 2019

Abstract
Locally produced osteoclastogenic factor RANKL plays a critical role in the development of bone resorption in periradicular periodontitis. However, because RANKL is also required for healthy bone remodeling, it is plausible that a costimulatory molecule that upregulates RANKL production in inflammatory periradicular periodontitis may be involved in the pathogenic bone loss processes. We hypothesized that macrophage migration inhibitory factor (MIF) would play a role in upregulating the RANKL-mediated osteoclastogenesis in the periradicular lesion. In response to pulp exposure, the bone loss and level of MIF mRNA increased in the periradicular periodontitis, which peaked at 14 d, in conjunction with the upregulated expressions of mRNAs for RANKL, proinflammatory cytokines (TNF-α, IL-6, and IL-1β), chemokines (MCP-1 and SDF-1), and MIF’s cognate receptors CXCR4 and CD74. Furthermore, expressions of those mRNAs were found significantly higher in wild-type mice compared with that of MIF−/− mice. In contrast, bacterial LPS elicited the production of MIF from ligament fibroblasts in vitro, which, in turn, enhanced their productions of RANKL and TNF-α. rMIF significantly upregulated the number of TRAP+ osteoclasts in vitro. Finally, periapical bone loss induced in wild-type mice were significantly diminished in MIF−/− mice. Altogether, the current study demonstrated that MIF appeared to function as a key costimulatory molecule to upregulate RANKL-mediated osteoclastogenesis, leading to the pathogenically augmented bone resorption in periradicular lesions. These data also suggest that the approach to neutralize MIF activity may lead to the development of a therapeutic regimen for the prevention of pathogenic bone loss in periradicular periodontitis.
Programming Effects of Pubertal Lipopolysaccharide Treatment in Male and Female CD-1 Mice
Authors: Sharma Rupali , van Mil Spencer , Melanson Brett , Thomas Bronwen J. , Rooke Jasmine , Mallet Jean-François , Matar Chantal , Schwarz Jaclyn M. , Ismail Nafissa 
Published: February 2019

Abstract
Puberty is a critical period of development marked by sexual, immune, and neural maturation. Exposure to stress during this period can lead to enduring changes in brain functioning and in behavior; however, the underlying mechanisms and the programming effects of stress during puberty remain unknown. Therefore, the objective of this study was to investigate the programming effects of pubertal immune challenge in response to a homotypic stressor later in life in CD-1 mice. Age and sex differences in the peripheral and central cytokine levels, along with sickness behavior and telemetry data, were analyzed following the secondary treatment. The results showed that pretreatment with LPS attenuated the immune response to a second homotypic challenge. Males pretreated with LPS during puberty and in early adulthood displayed an attenuated hypothermic response following the second LPS treatment compared with saline-pretreated controls, which is consistent with the attenuated peripheral IL-6 and IFN-γ concentrations. Females pretreated with LPS during puberty displayed lower IL-1β, TNF-α, and IL-6 mRNA expression in the prefrontal cortex following the secondary immune challenge compared with saline controls. The results of this study show that exposure to LPS during puberty programs the peripheral and central immune responses, resulting in an attenuated immune response following a subsequent homotypic stressor. Thus, exposure to an immune challenge during puberty affects immune function later in life, which could permanently affect brain function and have implications on mental health.
New Insights into Lymphocyte Differentiation and Aging from Telomere Length and Telomerase Activity Measurements
Authors: Fali Tinhinane , Papagno Laura , Bayard Charles , Mouloud Yanis , Boddaert Jacques , Sauce Delphine , Appay Victor 
Published: February 2019

Abstract
αβ CD8+, γδ, and NK lymphocytes are fundamental effector cells against viruses and tumors. These cells can be divided into multiple subsets according to their phenotype. Based on progressive telomere attrition from naive to late effector memory cells, human CD8+ T cell subsets have been positioned along a pathway of differentiation, which is also considered as a process of lymphocyte aging or senescence. A similar categorization has not been clearly established for γδ and NK cell populations. Moreover, the distinction between the aging of these populations due to cellular differentiation or due to the chronological age of the donor has not been formally considered. In this study, we performed systematic measurements of telomere length and telomerase activity in human αβ CD8+, γδ, and NK lymphocytes based on subset division and across age to address these points and better understand the dichotomy between differentiation and temporal aging. This approach enables us to position phenotypically distinct γδ or NK subsets along a putative pathway of differentiation, such as for CD8+ T cells. Moreover, our data show that both cellular differentiation and donor aging have profound but independent effects on telomere length and telomerase activity of lymphocyte subpopulations, implying distinct mechanisms and consequences on the immune system.
Evidence for a major missing source in the global chloromethane budget from stable carbon isotopes
Authors: Bahlmann Enno , Keppler Frank , Wittmer Julian , Greule Markus , Schöler Heinz Friedrich , Seifert Richard , Zetzsch Cornelius 
Published: February 2019

Abstract. Chloromethane
(CH3Cl) is the most important natural input of reactive chlorine to
the stratosphere, contributing about 16 % to stratospheric ozone
depletion. Due to the phase-out of anthropogenic emissions of
chlorofluorocarbons, CH3Cl will largely control future levels of
stratospheric chlorine. The tropical rainforest is commonly assumed to be the strongest single
CH3Cl source, contributing over half of the global annual emissions
of about 4000 to 5000 Gg (1 Gg = 109 g). This source shows a
characteristic carbon isotope fingerprint, making isotopic investigations a
promising tool for improving its atmospheric budget. Applying carbon isotopes
to better constrain the atmospheric budget of CH3Cl requires sound
information on the kinetic isotope effects for the main sink processes: the
reaction with OH and Cl in the troposphere. We conducted photochemical
CH3Cl degradation experiments in a 3500 dm3 smog chamber to
determine the carbon isotope effect (ε=k13C/k12C-1) for the reaction of CH3Cl with OH
and Cl. For the reaction of CH3Cl with OH, we determined an
ε value of (-11.2±0.8) ‰ (n=3) and for the
reaction with Cl we found an ε value of (-10.2±0.5) ‰ (n=1), which is 5 to 6 times smaller than previously
reported. Our smaller isotope effects are strongly supported by the lack of
any significant seasonal covariation in previously reported tropospheric
δ13C(CH3Cl) values with the OH-driven seasonal cycle in
tropospheric mixing ratios. Applying these new values for the carbon isotope effect to the global
CH3Cl budget using a simple two hemispheric box model, we derive a
tropical rainforest CH3Cl source of (670±200) Gg a−1,
which is considerably smaller than previous estimates. A revision of
previous bottom-up estimates, using above-ground biomass instead of
rainforest area, strongly supports this lower estimate. Finally, our results
suggest a large unknown CH3Cl source of (1530±200) Gg a−1.
Impact of assimilating sea ice concentration, sea ice thickness and snow depth in a coupled ocean–sea ice modelling system
Authors: Fritzner Sindre , Graversen Rune , Christensen Kai H. , Rostosky Philip , Wang Keguang 
Published: February 2019

Abstract. The accuracy of the initial state is very important for the
quality of a forecast, and data assimilation is crucial for obtaining the
best-possible initial state. For many years, sea-ice concentration was the
only parameter used for assimilation into numerical sea-ice models. Sea-ice
concentration can easily be observed by satellites, and satellite
observations provide a full Arctic coverage. During the last decade, an
increasing number of sea-ice related variables have become available, which
include sea-ice thickness and snow depth, which are both important parameters
in the numerical sea-ice models. In the present study, a coupled
ocean–sea-ice model is used to assess the assimilation impact of sea-ice
thickness and snow depth on the model. The model system with the assimilation
of these parameters is verified by comparison with a system assimilating only
ice concentration and a system having no assimilation. The observations
assimilated are sea ice concentration from the Ocean and Sea Ice Satellite
Application Facility, thin sea ice from the European Space Agency's
(ESA) Soil Moisture and Ocean Salinity mission, thick sea ice from
ESA's CryoSat-2 satellite, and a new snow-depth product derived from the
National Space Agency's Advanced Microwave Scanning Radiometer
(AMSR-E/AMSR-2) satellites. The model results are verified by comparing
assimilated observations and independent observations of ice concentration
from AMSR-E/AMSR-2, and ice thickness and snow depth from the IceBridge
campaign. It is found that the assimilation of ice thickness strongly
improves ice concentration, ice thickness and snow depth, while the snow
observations have a smaller but still positive short-term effect on snow
depth and sea-ice concentration. In our study, the seasonal forecast showed
that assimilating snow depth led to a less accurate long-term estimation of
sea-ice extent compared to the other assimilation systems. The other three
gave similar results. The improvements due to assimilation were found to last
for at least 3–4 months, but possibly even longer.
A ESTÉTICA DA AUSÊNCIA NA ESCULTURA CINÉTICA DE HEINER GOEBBELS
Authors: Andrade Eduardo Dos Santos 
Published: February 2019

Ao prescindir do drama, da narrativa, dos atores e dos músicos para a execução de sua peça-concerto intitulada Stifters Dinge,o maestro e artista multimídia alemão Heiner Goebbels expande os limites que tradicionalmente cercam a ideia de teatralidade. Essa expansão, entretanto, não é nova e nem tampouco incomum no universo da arte contemporânea, caracterizado por intercontaminações e hibridismos. Na ausência de performers humanos, Stifters Dingeparece ser ao mesmo tempo uma instalação, um concerto e um teatro, porém, tudo o que há são coisas sendo elas mesmas: coisas. A partir desta obra de Goebbels, junto ao seu conceito de “Estética da Ausência”, este artigo propõe uma breve reflexão acerca da teatralidade das coisas, buscando entender como os elementos espaço-visuais da cena, na sua natureza inanimada, podem ser identificados como agente performativos, carregados de uma dimensão humana implícita sem apresentar necessariamente um caráter antropomórfico.
Peran intensitas komunikasi, kepercayaan, dan dukungan sosial terhadap kebahagiaan perkawinan pada istri tentara saat menjalani Long Distance Marriage (LDM) di Batalyon Infanteri 407/Padmakusuma Kabupaten Tegal
Authors: Muhardeni Riza 
Published: February 2019

Penelitian ini bertujuan untuk mengetahui peran intensitas komunikasi, kepercayaan dan dukungan sosial terhadap kebahagiaan perkawinan pada istri tentara saat menjalani long distance marriage. Data dikumpulkan dengan menggunakan kuesioner berisi skala kebahagiaan perkawinan, skala intensitas perkawinan, skala kepercayaan perkawinan serta skala dukungan sosial. Jumlah subjek dalam penelitian ini 80 orang istri tentara yang ditinggal tugas oleh suaminya dan menetap di asrama Batalyon. Teknik analisis data yang digunakan dalam penelitian ini adalah analisis regresi linier berganda. Berdasarkan hasil analisis regresi berganda diperoleh kesimpulan: (1) terdapat peran intensitas komunikasi, kepercayaan dan dukungan sosial terhadap kebahagiaan perkawinaan pada istri tentara saat menjalani long distance marriage, diperoleh R2= .68, F (3, 76)= 54,56, p<0,001; (2) ada peran intensitas komunikasi perkawinan terhadap kebahagiaan perkawinan pada istri tentara saat menjalani long distance marriage (b= .45, p<.001) (3) ada peran kepercayaan perkawinan terhadap kebahagiaan perkawinan pada istri tentara saat menjalani long distance marriage, diperoleh (b= .59, p<.001); (4) tidak ada peran dukungan sosial terhadap kebahagiaan perkawinan pada istri tentara saat menjalani long distance marriage (b= 0,18, p=.054).
Assessment of prostate cancer prognostic Gleason grade group using zonal‐specific features extracted from biparametric MRI using a KNN classifier
Authors: Jensen Carina , Carl Jesper , Boesen Lars , Langkilde Niels Christian , Østergaard Lasse Riis 
Published: February 2019

AbstractPurposeTo automatically assess the aggressiveness of prostate cancer (PCa) lesions using zonal‐specific image features extracted from diffusion weighted imaging (DWI) and T2W MRI.MethodsRegion of interest was extracted from DWI (peripheral zone) and T2W MRI (transitional zone and anterior fibromuscular stroma) around the center of 112 PCa lesions from 99 patients. Image histogram and texture features, 38 in total, were used together with a k‐nearest neighbor classifier to classify lesions into their respective prognostic Grade Group (GG) (proposed by the International Society of Urological Pathology 2014 consensus conference). A semi‐exhaustive feature search was performed (1–6 features in each feature set) and validated using threefold stratified cross validation in a one‐versus‐rest classification setup.ResultsClassifying PCa lesions into GGs resulted in AUC of 0.87, 0.88, 0.96, 0.98, and 0.91 for GG1, GG2, GG1 + 2, GG3, and GG4 + 5 for the peripheral zone, respectively. The results for transitional zone and anterior fibromuscular stroma were AUC of 0.85, 0.89, 0.83, 0.94, and 0.86 for GG1, GG2, GG1 + 2, GG3, and GG4 + 5, respectively.CONCLUSIONThis study showed promising results with reasonable AUC values for classification of all GG indicating that zonal‐specific imaging features from DWI and T2W MRI can be used to differentiate between PCa lesions of various aggressiveness.
Photogenerated Charge Transport in Organic Electronic Materials: Experiments Confirmed by Simulations
Authors: Melianas Armantas , Kemerink Martijn 
Published: February 2019

AbstractThe performance of organic optoelectronic devices, such as organic photovoltaic (OPV) cells, is to a large extent dictated by their ability to transport the photogenerated charge, with relevant processes spanning a wide temporal (fs–µs) and spatial (1–100 nm) range. However, time‐resolved techniques can access only a limited temporal window, and often contradict steady‐state measurements. Here, commonly employed steady‐state and time‐resolved techniques are unified over an exceptionally wide temporal range (fs–µs) in a consistent physical picture. Experimental evidence confirmed by numerical simulations shows that, although various techniques probe different time scales, they are mutually consistent as they probe the same physical mechanisms governing charge motion in disordered media—carrier hopping and thermalization in a disorder‐broadened density of states (DOS). The generality of this framework is highlighted by time‐resolved experimental data obtained on polymer:fullerene, polymer:polymer, and small‐molecule blends with varying morphology, including recent experiments revealing that low donor content OPV devices operate by long‐range hole tunneling between non‐nearest‐neighbor molecules. The importance of nonequilibrium processes in organic electronic materials is reviewed, with a particular focus on experimental data and understanding charge transport physics in terms of material DOS.