bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Deep Chandra View of a Candidate Parsec-scale Jet from the Galactic Center Supermassive Black Hole
Authors: Zhu Zhenlin , Li Zhiyuan , Morris Mark R. , Zhang Shuo , Liu Siming 
Published: April 2019

Abstract
We have investigated the linear X-ray filament, G359.944−0.052, previously identified as a likely X-ray counterpart of a parsec-scale jet from the Galactic Center supermassive black hole (SMBH) Sagittarius A* (Sgr A*), using a total of ∼5.6 Ms ultra-deep Chandra observations taken from 1999 September to 2017 July. This unprecedented data set enables us to examine flux and spectral variations that might be related to intrinsic properties of the weakly accreting SMBH. We find no flux or spectral variation in G359.944−0.052 after the G2 periapsis passage around early 2014; however, a moderate flux increase of ∼2σ significance might be associated with the periapsis passage of G1 in early 2001. The filament exhibits an unusually hard spectrum (photon index ≲1) in its portion closest to Sgr A* (i.e., near side) and a significant spectral softening in the more distant portion, which can be interpreted as synchrotron cooling of the relativistic electrons moving along the jet path. In particular, the hard spectrum of the near side suggests a piling up of quasi-monoenergetic electrons caused by rapid radiative cooling. The spectral and temporal properties of G359.944−0.052 strengthen the case for it being the X-ray counterpart of a jet launched by Sgr A*.
Effect of Different Angular Momentum Transport Mechanisms on the Distribution of Water in Protoplanetary Disks
Authors: Kalyaan Anusha , Desch Steven J. 
Published: April 2019

Abstract
The snow line in a protoplanetary disk demarcates regions with H2O ice from regions with H2O vapor. Where a planet forms relative to this location determines how much water and other volatiles it forms with. Giant-planet formation may be triggered at the water–snow line if vapor diffuses outward and is cold-trapped beyond the snow line faster than icy particles can drift inward. In this study, we investigate the distribution of water across the snow line, considering three different radial profiles of the turbulence parameter α(r), corresponding to three different angular momentum transport mechanisms. We consider the radial transport of water vapor and icy particles by diffusion, advection, and drift. We show that even for similar values of α, the gradient of α(r) across the snow line significantly changes the snow line location, the sharpness of the volatile gradient across the snow line, and the final water/rock ratio in planetary bodies. A profile of radially decreasing α, consistent with transport by hydrodynamic instabilities plus magnetic disk winds, appears consistent with the distribution of water in the solar nebula, with monotonically increasing radial water content and a diverse population of asteroids with different water content. We argue that Σ(r) and water abundance

are likely a diagnostic of α(r) and thus of the mechanism for angular momentum transport in inner disks.
Chroniques de ‘carrières’. Des trajectoires créatives sous fortes influences socio-économiques
Authors: Buscatto Marie 
Published: April 2019

Les industries culturelles se caractérisent par une forte prégnance de l’emploi ponctuel, flexible, incertain et à durée limitée. Ces conditions d’emploi et de travail sont le plus souvent justifiées par les employeurs aussi bien par la structuration de l’activité autour de projets non récurrents – un film, un jeu vidéo, une pièce de théâtre, une émission de radio, un disque ou une exposition -, que par la flexibilité que nécessiterait la haute intensité créative de l’activité. Les individus très qualifiés évoluant dans ces industries culturelles – e.g. designers, artistes, producteurs, concepteurs de jeux vidéos, critiques, cinéastes, attachés de presse, traducteurs, ingénieurs du son ou éditeurs - se trouvent ainsi dans des situations professionnelles incertaines et suivent des trajectoires a priori peu définies faute d’insertion dans des structures organisationnelles pérennes. Peut-on, au-delà de la forte incertitude, variabilité et flexibilité des emplois caractérisant ces secteurs d’activité, envisager l’identification de trajectoires idéales typiques relativement stables organisant l’évolution dans le temps de ces travailleurs ? Et la reconstitution systématique de ces carrières dans leur complétude et leur diversité n’enrichirait-elle pas notre compréhension des dynamiques constitutives de ces modes d’emploi et de travail ?Telle est l’approche originale construite dans cet article à travers l’exemple de la chronique jazz en France.
FGFR2 Promotes Expression of PD-L1 in Colorectal Cancer via the JAK/STAT3 Signaling Pathway
Authors: Li Piao , Huang Tingting , Zou Qi , Liu Dian , Wang Yihua , Tan Ximin , Wei Yao , Qiu Hong 
Published: April 2019

Abstract
Although multidisciplinary treatment is widely applied in colorectal cancer (CRC), the prognosis of patients with advanced CRC remains poor. Immunotherapy blocking of programmed cell death ligand 1 (PD-L1) is a promising approach. Binding of the transmembrane protein PD-L1 expressed by tumor cells or tumor microenvironment cells to its receptor programmed cell death 1 (PD-1) induces immunosuppressive signals and reduces the proliferation of T cells, which is an important mechanism of tumor immune escape and a key issue in immunotherapy. However, the regulation of PD-L1 expression is poorly understood in CRC. Fibroblast growth factor (FGF) receptor (FGFR) 2 causes the tyrosine kinase domains to initiate a cascade of intracellular signals by binding to FGFs and dimerization (pairing of receptors), which is involved in tumorigenesis and progression. In this study, we showed that PD-L1 and FGFR2 were frequently overexpressed in CRC, and FGFR2 expression was significantly associated with lymph node metastasis, clinical stage, and poor survival. In the current study, PD-L1 expression was positively correlated with FGFR2 expression in CRC. Tumor-derived–activated FGFR2 induced PD-L1 expression via the JAK/STAT3 signaling pathway in human CRC cells (SW480 and NCI-H716), which induced the apoptosis of Jurkat T cells. FGFR2 also promoted the expression of PD-L1 in a xenograft mouse model of CRC. The results of our study reveal a novel mechanism of PD-L1 expression in CRC, thus providing a theoretical basis for reversing the immune tolerance of FGFR2 overexpression in CRC.
Risk management in a bulk coal export logistic chain: A stakeholder perspective
Authors: Botha André , Badenhorst-Weiss J. A. 
Published: April 2019

Background: In South Africa, the export of coal is a large contributor to the gross domestic product. Statistics indicate that the export of coal is stagnant or declining, which indicates a risk for coal as a foreign exchange earner. A study into the risks facing the bulk coal export logistics chain is therefore of great importance. Any risk to this logistics chain will directly affect its efficiency and contribution to foreign exchange. The nature of a logistics supply chain is such that risks to one stakeholder (partner or node) affect not only that stakeholder’s own operations but also those of the other partners and the whole supply chain’s efficiency and sustainability.Objectives: The objective of the study was to identify and explore the risks and risk management practices in the bulk coal export logistics chain from a stakeholder theory perspective.Methods: A qualitative research design was used, and in-depth, structured interviews were conducted with different stakeholders in the chain. A total of eight interviews were conducted, audio-recorded, transcribed and analysed by means of a thematic analysis.Results: Many risks were identified in the bulk coal export logistics chain, and of these risks, it was found that the most important ones were infrastructure, the macro-economy and people-related risks. The findings revealed evidence of underlying tensions between different stakeholders with regard to investment to mitigate infrastructure risks. The findings suggest that there is a lack of communication and an aligned vision among the stakeholders in the logistics chain and that they strategise for their risks separately.Conclusion: Close cooperation on a high level between the stakeholders in the logistics chain is needed to strategise for risk mitigation in an integrated, holistic manner.
Identification of soil-cooling rains in southern France from soil temperature and soil moisture observations
Authors: Zhang Sibo , Meurey Catherine , Calvet Jean-Christophe 
Published: April 2019

Abstract. In this study, the frequency and intensity of soil-cooling rains is assessed
using in situ observations of atmospheric and soil profile variables in
southern France. Rainfall, soil temperature, and topsoil volumetric soil
moisture (VSM) observations, measured every 12 min at 21 stations of the
SMOSMANIA (Soil Moisture Observing System – Meteorological Automatic Network
Integrated Application) network, are analyzed over a time period of 9 years,
from 2008 to 2016. The spatial and temporal statistical distribution of the
observed rainfall events presenting a marked soil-cooling effect is
investigated. It is observed that the soil temperature at a depth of 5 cm
can decrease by as much as 6.5 ∘C in only 12 min during a
soil-cooling rain. We define marked soil-cooling rains as rainfall events
triggering a drop in soil temperature at a depth of 5 cm larger than
1.5 ∘C in 12 min. Under Mediterranean and
Mediterranean–mountain climates, it is shown that such events occur up to nearly
3 times a year, and about once a year on average. This frequency decreases to
about once every 3.5 years under semi-oceanic climate. Under oceanic climate,
such pronounced soil-cooling rains are not observed over the considered
period of time. Rainwater temperature is estimated for 13 cases of marked
soil-cooling rains using observed changes within 12 min in soil temperature
at a depth of 5 cm, together with soil thermal properties and changes in
VSM. On average, the estimated rainwater temperature is generally lower than
the observed ambient air temperature, wet-bulb temperature, and topsoil
temperature at a depth of 5 cm, with mean differences of −5.1, −3.8, and
−11.1 ∘C, respectively. The most pronounced differences are
attributed to hailstorms or to hailstones melting before getting to the soil
surface. Ignoring this cooling effect can introduce biases in land surface
energy budget simulations.
Inputs and processes affecting the distribution of particulate iron in the North Atlantic along the GEOVIDE (GEOTRACES GA01) section
Authors: Gourain Arthur , Planquette Hélène , Cheize Marie , Lemaitre Nolwenn , Menzel Barraqueta Jan-Lukas , Shelley Rachel , Lherminier Pascale , Sarthou Géraldine 
Published: April 2019

Abstract. The aim of the GEOVIDE cruise (May–June 2014, R/V Pourquoi Pas?)
was to provide a better understanding of trace metal biogeochemical cycles in
the North Atlantic Ocean. As marine particles play a key role in the global
biogeochemical cycle of trace elements in the ocean, we discuss the
distribution of particulate iron (PFe), in relation to the distribution of
particulate aluminium (PAl), manganese (PMn), and phosphorus (PP). Overall,
32 full vertical profiles were collected for trace metal analyses,
representing more than 500 samples. This resolution provides a solid basis
for assessing concentration distributions, elemental ratios, size
fractionation, and adsorptive scavenging processes in key areas of the
thermohaline overturning circulation. Total particulate iron concentrations
ranged from as low as 9 pmol L−1 in surface waters of the Labrador Sea
to 304 nmol L−1 near the Iberian margin, while median PFe
concentrations of 1.15 nmol L−1 were measured over the sub-euphotic
ocean interior. Within the Iberian Abyssal Plain, the ratio of PFe to PAl was identical to
the continental crust molar ratio (0.21 mol mol−1), indicating the
important influence of crustal particles in the water column. Overall, the
lithogenic component explained more than 87% of PFe variance along the
section. Within the Irminger and Labrador basins, the formation of biogenic
particles led to an increase in the PFe∕PAl ratio (up to
0.64 mol mol−1) compared to the continental crust ratio. Continental
margins induce high concentrations of particulate trace elements within the
surrounding water masses (up to 10 nmol L−1 of PFe). For example,
horizontal advection of PFe was visible more than 250 km away from the
Iberian margin. Additionally, several benthic nepheloid layers were observed
more than 200 m above the seafloor along the transect, especially in the
Icelandic, Irminger, and Labrador basins, suspending particles with high PFe
content of up to 89 nmol L−1.
Modos de empleo del Détournement. Estrategias e intervenciones para una crítica dialéctica de situaciones
Authors: Percia Violeta 
Published: April 2019

En la bisagra del Mayo Francés, tal como aparece en los textos letristas de Guy Debord y Gil Wolman, en los oce números de la revista Internationale Situationniste, y a la luz del tratamiento más sistemático que le dio Debord en La sociedad del Espectáculo (1967), este trabajo propone una revisión de la noción de détournement – strategia fundamental de la resistencia comunicacional situacionista, camino posible para una crítica dialéctica de situaciones y para una reescritura crítica de las ideas.
A biblioteca do futuro: um olhar no passado
Authors: Jesus Deise Lourenço de , Cunha Murilo Bastos da 
Published: April 2019

Introdução: Em 1929, McDevitt já relatava que grandes mudanças ocorreriam nas bibliotecas e os problemas que elas enfrentariam estariam mais relacionados aos recursos financeiros do que a tecnologia propriamente. Isto acabou não sendo o grande obstáculo das bibliotecas e são as mudanças e os avanços da tecnologia que colocam em risco a sobrevivência da biblioteca tradicional. Objetivo: O trabalho propõe apresentar ideias de autores da Biblioteconomia e da Ciência da Informação sobre a biblioteca do futuro e as mudanças tecnológicas e sociais que estas sofreriam nos anos seguintes. Metodologia: Revisão de literatura que cobre o período de 1945 a 2003. Resultados: A pesquisa revela que a literatura central em torno das bibliotecas remete à transição do físico para o digital, e todo o processo que as bibliotecas deveriam passar em termos financeiros, de pessoal e de tecnologias, além de possíveis barreiras e limitações para essa transição. Conclusões: Conclui-se que mesmo com todo o potencial previsto para o desenvolvimento da biblioteca digital, o movimento de transição não aconteceu tão rápido nem na mesma proporção que os autores imaginaram e que a transição ainda não está completa.
Um estudo das contribuições de Schopenhauer para a Ciência da Informação: o mundo como vontade e representação
Authors: Sousa Janailton Lopes , Sá Ramalho Rogério Aparecido 
Published: April 2019

Introdução: Arthur Schopenhauer foi um filósofo alemão do século XIX autor do livro intitulado 'O Mundo como Vontade e Representação', publicado originalmente em 1819, onde aborda a complexa relação entre representação e o modo como o homem interpreta a realidade. Objetivo: Analisar as contribuições de Arthur Schopenhauer, identificadas na obra 'O Mundo como Vontade e Representação', verificando aproximações com corpus teórico da Ciência da Informação, principalmente em relação aos trabalhos desenvolvidos por Wittgenstein (1968) e Dahlberg (1978), referentes ao estudo da Linguagem e Teoria do Conceito. Metodologia: A pesquisa enquadra-se como teórica, de caráter analítico e utilizou como procedimentos metodológicos atividades de revisão, análise e interpretação da literatura selecionada. Resultados: A partir do estudo realizado foi possível inferir que os trabalhos desenvolvidos por Wittgenstein (1968) e Dahlberg (1978) no âmbito da área de Ciência da Informação foram influenciados pela concepção de representação apresentada na obra de Schopenhauer, considerando que as representações fundamentam o entendimento humano sobre o funcionamento da realidade como se conhece, desenvolvidas como formas para codificar a natureza, e as relações entre os seres, em uma linguagem assimilável à razão. Conclusões: Schopenhauer oferece uma concepção de representação que pode ser incorporada no campo da Ciência da Informação, pois entende que os conceitos são elementos chave da representação, abarcando a relação sujeito e objeto, o conhecimento seria o resultado dessa relação e uma forma de representação do mundo.
Competência em informação no âmbito da comunidade LGBTQ: um levantamento das publicações científicas nacionais e internacionais
Authors: Ottonicar Selma Leticia Capinzaiki , Brito Jean Fernandes , Silva Rafaela Carolina , Barbosa Everaldo Henrique dos Santos , Moraes Cassia Regina Bassan de 
Published: April 2019

Introdução: A comunidade LGBTQ tem enfrentado dificuldades na sociedade contemporânea devido ao preconceito de alguns indivíduos. Atualmente, as leis de diversos países, bem como as políticas públicas têm sido direcionadas a esses grupos, para incluí-los em sociedade. O foco é garantir o direito aos seres humanos e o respeito às minorias, objetivando melhorar a qualidade de vida dessas pessoas. Perante tais reflexões, o problema de pesquisa buscou refletir as maneiras pelas quais a competência em informação pode contribuir para que a sociedade desenvolva o respeito à comunidade LGBT. Objetivos: O artigo objetiva demonstrar os modos pelos quais a literatura da Ciência da Informação tem tratado a temática, a fim de incluir a comunidade LGBT em suas pesquisas. Não obstante, objetiva-se demonstrar como a competência em informação pode contribuir para que a comunidade LGBTQ seja respeitada em sociedade. Metodologia: A metodologia envolve uma revisão sistemática da literatura na área da Ciência da Informação sobre a competência em informação e o movimento LGBT, a fim de identificar como o tema vem sendo tratado pela área. Resultados: Os temas são trabalhados de maneira tímida pela área, tanto em nível nacional quanto internacional. Além disso, desenvolveu-se um modelo de respeito ao LGBTQ por meio desta competência, a fim de ser aplicado em diversos contextos de modo a reduzir o preconceito com estas pessoas. Conclusões: Existe a necessidade de pesquisas aprofundados sobre a temática. O uso da informação eficaz contribui para a compreensão do contexto dos LGBTQ e o respeito ao seu modo de vida.
Do the regular annual extreme water level changes affect the seasonal appearance of Anabaena in Poyang Lake?
Authors: Qian Kuimei , Dokulil Martin , Chen Yuwei 
Published: April 2019

Background
Poyang Lake is an ecosystem experiencing annual variations in water level of up to 14 m. Water level changes were 8.03 and 11.22 m, respectively, in the years 2013 and 2014. The biomass and heterocyst frequency of Anabaena increased in the summers of recent years.

Methods
A weekly to bi-weekly monitoring from June to November 2013 and 2014 was set up to explain the variations of Anabaena appearance in different phases of the water level.

Results
Anabaena was present in the lake throughout the year. The average relative biomass of Anabaena in the present study was over 40%, being most abundant in summer. The average heterocyst frequency was 0.23% in 2013 and 0.76% in 2014. Correlation analysis indicated a positive trend of Anabaena biomass with water temperature and water level and a negative one with total nitrogen (TN), which is the reason for the increase of heterocyst frequency in 2013 and 2014. Heterocyst frequency of Anabaena was positively correlated with water temperature, water level and PO4-P, and negatively with dissolved inorganic nitrogen (DIN/DIP), NO3-N and TN. Moreover, water temperature and DIN/DIP were significantly correlated with water level, indicating that water level changes have a direct effect on Anabaena and heterocyst formation in Poyang Lake.

Conclusions
The results of this study support the hypothesis that increasing biomass and heterocyst formation of Anabaena can be primarily caused by seasonal changes of the water level in Poyang Lake.
The Effect of Nigella sativa and Piper guineense Aqueous Extracts on the in Vivo Expression Profile of Lipid and Sex Hormones
Authors: Franca Okoye Ngozi , Rume Uvbiekpahor 
Published: April 2019

Aim: The study investigated the effect of aqueous extract of Piper guineense and Nigella sativa on Testosterone, Estrogen and Follicle stimulating hormone levels in male and female rats induced by diets supplemented with high dose of sucrose and margarine for four (4) week.
Materials and Methods: Thirty male and female Wistar rats of average weight (100 g) were used for the study. The rats were arranged into five groups with six rats in each of the groups. The rats had access to their normal feed but sucrose and margarine were used to induce hyperglycemia and hyperlipidemia respectively on the rats with the exception of the rats in the positive control group. The rats in the negative control were induced using the sucrose and margarine but were not treated using the aqueous extracts. The rats in the Piper guineense group were treated with 2 ml of Piper guineense aqueous leaf extract, while the rats in the Nigella sativa group were treated with 2 ml of Nigella sativa aqueous extract. The rats in the Nigella sativa and Piper guineense group were treated with 2 ml of the combined aqueous extract.
Results: The results showed that the extracts had an increasing effect which was time dependent on the hormones. The highest increase was obtained on the third week of feeding when compared to the control. The testosterone levels (mlU/ml) showed for the, positive control (2.28 ± 0.08), uziza leaf (6.45 ± 0.01), black seed (2.85 ± 0.01), black seed &uziza (8.47 ± 0.08)(p<0.05). The increase for estrogen levels (mlU/ml) showed for the positive control (99 ± 0.82), uziza leaf (98 ± 1.63), black seed (100 ± 1.63), black seed & uziza (113 ± 0.82). Furthermore, the extracts also had an increasing effect on the follicle stimulating hormone levels with the highest increase obtained on the third week (p>0.05). The FSH levels (mlU/ml)) showed for the positive control (0.23 ± 0.01), uziza leaf 0.25 ± 0.01), black seed (0.54 ± 0.02), black seed & uziza (0.58 ± 0.01)(p<0.05).
Histopathological findings also suggest that treatment with the aqueous extracts of P.guineense and N .sativa after inducement salvaged the testes and ovaries when compared to the induced group after the second week of administration. Although the combined mixture N.sativa and P.guineense extract was more effective.
Conclusion: The results of the study indicate that the aqueous extract of a combined mixture of Nigella sativa and Piper guineense might be an effective plant in indigenous medicine, which may be used to combat infertility caused by hormonal imbalance.