bluuebunny/crossref_metadata_2025 huggingface dataset:
Xylanase, and the role of digestibility and hindgut fermentation in pigs on energetic differences among high and low energy corn samples1
Authors: Petry Amy L , Masey O’Neill Helen V , Patience John F
Published: August 2019

The experimental objective was to evaluate the digestibility and fermentation differences between high and low energy corn samples and their response to xylanase supplementation. Four corn samples, 2 with higher DE content (HE-1 and HE-2; 3.74 and 3.75 Mcal DE/kg DM, respectively) and 2 with a lower DE content (LE-1 and LE-2; 3.63 and 3.56 Mcal DE/kg DM, respectively) were selected based upon a previous digestibility trial. Sixteen individually housed barrows (PIC 359 × C29; initial BW = 34.8 ± 0.23kg) were surgically fitted with an ileal T-cannula and randomly allotted to treatments in an 8 × 4 Youden square design. Dietary treatments were arranged in a 4 × 2 factorial: HE-1, HE-2, LE-1, and LE-2, with and without xylanase supplementation. Diets were formulated using one of the 4 corn samples, casein, vitamins, minerals, and 0.4% chromic oxide as an indigestible marker. Feed intake was established at approximately 3 times the estimated energy required for maintenance (NRC 2012) based upon the average initial BW of the pigs at the start of each collection period, which consisted of 9 d adaptation, 2 d of fecal, and 3 d of ileal collections. Diets, ileal, and fecal samples were analyzed for DM, GE, and total dietary fiber (TDF), to determine apparent total tract (ATTD), hindgut fermentation (HF), apparent ileal digestibility (AID) coefficients. A diet × enzyme interaction was not observed for any of the measured variables (P > 0.10). The HE-1 and HE-2 diets had greater ATTD of GE, and HE-2 diet had greater ATTD of DM (P < 0.001 and P = 0.007, respectively). Xylanase, independent of diet, improved the ATTD of GE and DM (84.8 vs. 83.6% for GE with and without enzyme, respectively, P = 0.008; and 84.2 and 83.0% with and without enzyme, respectively, P = 0.007). The energetic differences among these corn samples appeared to be driven by fermentability in the hindgut. Supplementing xylanase improves digestibility irrespective of the digestibility energy content of corn.
Hypertrophic muscle growth and metabolic efficiency were impaired by chronic heat stress, improved by zilpaterol supplementation, and not affected by ractopamine supplementation in feedlot lambs1
Authors: Barnes Taylor L , Cadaret Caitlin N , Beede Kristin A , Schmidt Ty B , Petersen Jessica L , Yates Dustin T
Published: August 2019

Feedlot performance is reduced by heat stress and improved by β adrenergic agonists (βAA). However, the physiological mechanisms underlying these outcomes are not well characterized, and anecdotal reports suggest that βAA may confound the effects of heat stress on wellbeing. Thus, we sought to determine how heat stress and βAA affect growth, metabolic efficiency, and health indicators in lambs on a feedlot diet. Wethers (38.6 ± 1.9 kg) were housed under thermoneutral (controls; n = 25) or heat stress (n = 24) conditions for 21 d. In a 2 × 3 factorial, their diets contained no supplement (unsupplemented), ractopamine (β1AA), or zilpaterol (β2AA). Blood was collected on days −3, 3, 9, and 21. On day 22, lambs were harvested and ex vivo skeletal muscle glucose oxidation was determined to gauge metabolic efficiency. Feet and organ tissue damage was assessed by veterinary pathologists. Heat stress reduced (P < 0.05) feed intake by 21%, final bodyweight (BW) by 2.6 kg, and flexor digitorum superficialis (FDS) muscle mass by 5%. β2AA increased (P < 0.05) FDS mass/BW by 9% and average muscle fiber area by 13% compared with unsupplemented lambs. Blood lymphocytes and monocytes were greater (P < 0.05) in heat-stressed lambs, consistent with systemic inflammation. Plasma insulin was 22% greater (P < 0.05) and glucose/insulin was 16% less (P < 0.05) in heat-stressed lambs than controls. Blood plasma urea nitrogen was increased (P < 0.05) by heat stress on day 3 but reduced (P < 0.05) on days 9 and 21. Plasma lipase and lactate dehydrogenase were reduced (P < 0.05) by heat stress. Glucose oxidation was 17% less (P < 0.05) in muscle from heat-stressed lambs compared with controls and 15% greater (P < 0.05) for β2AA-supplemented compared with unsupplemented lambs. Environment and supplement interacted (P < 0.05) for rectal temperature, which was increased (P < 0.05) by heat stress on all days but more so (P < 0.05) in β2AA-supplemented lambs on days 4, 9, and 16. Heat stress increased (P < 0.05) the frequency of hoof wall overgrowth, but βAA did not produce any pathologies. We conclude that reduced performance in heat-stressed lambs was mediated by reduced feed intake, muscle growth, and metabolic efficiency. β2AA increased muscle growth and improved metabolic efficiency by increasing muscle glucose oxidation, but no such effects were observed with ractopamine. Finally, βAA supplementation was not detrimental to health indicators in this study, nor did it worsen the effects of heat stress.
Allometric growth, sexual maturity, and life cycle of Aegla lata (Decapoda, Anomura), a critically endangered species
Authors: Chaves Mariane R , Marçal Ingrid C , Shimizu Roberto M , Bueno Sérgio Ls , Teixeira Gustavo M
Published: August 2019

Aegla lata Bond-Buckup & Buckup, 1994 is a critically endangered species, extinct in its type-locality. Its currently known geographical distribution is restricted to small streams of the lower Tibagi River Basin (Paraná state, southern Brazil), where it is vulnerable to the environmental degradation that takes place in these watersheds. Scientific knowledge on the species is limited to the original description and a few occurrence records. No information about its biology is available. Aiming to fill this gap, we investigated the relative growth, sexual maturity, sexual dimorphism, and the reproductive and recruitment periods of A. lata. Monthly sampling occurred from May 2014 through June 2015 in the Bule stream in the southern limit of Mata dos Godoy State Park, Londrina, Paraná state, Brazil (23°27ʹ20.86″S, 51°16ʹ32.44″W). The analysis of allometric growth was used to differentiate juveniles and adults. According to the development stage of the chelae, two sequential groups of adult males were recognized (morphotypes I and II). The estimated average cephalothorax length (CL) at the onset of morphometric maturity of males and females are similar, suggesting puberty molt takes place at nearly the same size in both sexes. Males and females are heterochelous, with a clear predominance of the left chela as the most developed of the pair. Both chelae are larger in adult males than in adult females of similar CL. The reproductive period is markedly seasonal, extending from the austral autumn to winter (May to August), as well as those recorded in other species of Aegla from similar latitudes. A single annual recruitment pulse was detected from October 2014 to February 2015.
Surgical-related risk factors associated with anastomotic leakage after resection for rectal cancer: a meta-analysis
Authors: Wang Xiao-Tong , Li Lei , Kong Fan-Biao , Zhong Xiao-Gang , Mai Wei
Published: August 2019

Objectives

Anastomotic leakage (AL) after anterior resection always leads to longer hospital stays, decreased quality of life and even increased mortality. Despite extensive research, no consensus on the world well-concerned surgical-related risk factors exists. We therefore conducted a meta-analysis of the available published literature to identify the effects of surgical-related risk factors for AL after anterior resection for rectal cancer, hoping to provide more information and improved guidance for clinical workers managing patients with rectal cancer who are at a high risk for AL.

Methods

In this study, the relevant articles were systematically searched from EMBASE, MEDLINE, PubMed, WangFang (Database of Chinese Ministry of Science & Technology), Chinese National Knowledge Infrastructure Database and China Biological Medicine Database. The pooled odds ratio (OR) with 95% confidence interval (95% CI) were calculated. Meta-analysis was performed using of RevMan 5.3 software.

Results

A total of 26 studies met the inclusion criteria and comprised 34238 cases. Analysis of these 26 studies showed that no defunctioning stoma was highly correlated with AL (pooled OR = 1.28, 95%CI: 1.05–1.57, P = 0.01, random effect), and intraoperative blood transfusion was significantly associated with AL (pooled OR = 1.64, 95%CI: 1.34–2.02, P = 0.02, random effect). However, the AL was not associated with type of anastomosis, type of surgery, technique of anastomosis, level of inferior mesenteric artery ligation, operation time and splenic flexure mobilization.

Conclusions

Depend on this meta-analysis, no defunctioning stoma and intraoperative blood transfusion are the major surgical-related risk factors for AL after resection for rectal cancer. Because of the inherent limitations of the research, future prospective randomized controlled trials will need to confirm this conclusion.
Prediagnostic Plasma Bile Acid Levels and Colon Cancer Risk: A Prospective Study
Authors: Kühn Tilman , Stepien Magdalena , López-Nogueroles Marina , Damms-Machado Antje , Sookthai Disorn , Johnson Theron , Roca Marta , Hüsing Anika , Maldonado Sandra González , Cross Amanda J , Murphy Neil , Freisling Heinz , Rinaldi Sabina , Scalbert Augustin , Fedirko Veronika , Severi Gianluca , Boutron-Ruault Marie-Christine , Mancini Francesca Romana , Sowah Solomon A , Boeing Heiner , Jakszyn Paula , Sánchez Maria J , Merino Susana , Colorado-Yohar Sandra , Barricarte Aurelio , Khaw Kay Tee , Schmidt Julie A , Perez-Cornago Aurora , Trichopoulou Antonia , Karakatsani Anna , Thriskos Paschalis , Palli Domenico , Agnoli Claudia , Tumino Rosario , Sacerdote Carlotta , Panico Salvatore , Bueno-de-Mesquita Bas , van Gils Carla H , Heath Alicia K , Gunter Marc J , Riboli Elio , Lahoz Agustín , Jenab Mazda , Kaaks Rudolf
Published: August 2019

Background

Bile acids have been proposed to promote colon carcinogenesis. However, there are limited prospective data on circulating bile acid levels and colon cancer risk in humans.

Methods

Associations between prediagnostic plasma levels of 17 primary, secondary, and tertiary bile acid metabolites (conjugated and unconjugated) and colon cancer risk were evaluated in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Bile acid levels were quantified by tandem mass spectrometry in samples from 569 incident colon cancer cases and 569 matched controls. Multivariable logistic regression analyses were used to estimate odds ratios (ORs) for colon cancer risk across quartiles of bile acid concentrations.

Results

Positive associations were observed between colon cancer risk and plasma levels of seven conjugated bile acid metabolites: the primary bile acids glycocholic acid (ORquartile 4 vs quartile 1= 2.22, 95% confidence interval [CI] = 1.52 to 3.26), taurocholic acid (OR = 1.78, 95% CI = 1.23 to 2.58), glycochenodeoxycholic acid (OR = 1.68, 95% CI = 1.13 to 2.48), taurochenodeoxycholic acid (OR = 1.62, 95% CI = 1.11 to 2.36), and glycohyocholic acid (OR = 1.65, 95% CI = 1.13 to 2.40), and the secondary bile acids glycodeoxycholic acid (OR = 1.68, 95% CI = 1.12 to 2.54) and taurodeoxycholic acid (OR = 1.54, 95% CI = 1.02 to 2.31). By contrast, unconjugated bile acids and tertiary bile acids were not associated with risk.

Conclusions

This prospective study showed that prediagnostic levels of certain conjugated primary and secondary bile acids were positively associated with risk of colon cancer. Our findings support experimental data to suggest that a high bile acid load is colon cancer promotive.
Brevity is the Soul of Twitter: The Constraint Affordance and Political Discussion
Authors: Jaidka Kokil , Zhou Alvin , Lelkes Yphtach
Published: August 2019

Many hoped that social networking sites would allow for the open exchange of information and a revival of the public sphere. Unfortunately, conversations on social media are often toxic and not conducive to healthy political discussions. Twitter, the most widely used social network for political discussions, doubled the limit of characters in a tweet in November 2017, which provided an opportunity to study the effect of technological affordances on political discussions using a discontinuous time series design. Using supervised and unsupervised natural language processing methods, we analyzed 358,242 tweet replies to U.S. politicians from January 2017 to March 2018. We show that doubling the permissible length of a tweet led to less uncivil, more polite, and more constructive discussions online. However, the declining trend in the empathy and respectfulness of these tweets raises concerns about the implications of the changing norms for the quality of political deliberation.
The Macrosecuritization of Antimicrobial Resistance in China
Authors: Thomas Nicholas , Lo Catherine Yuk-ping
Published: August 2019

The global spread of antimicrobial resistance (AMR) is an existential threat to humanity, one that has generated a macrosecuritizing response by states and international organizations. Since the turn of the century, China has been a source of numerous infectious disease outbreaks. It is also the origin of the MCR-1 gene, which confers resistance to colistin, a “last-line” antibiotic deployed against multidrug-resistant infections. With the largest population in the world, coupled with its status as a major supplier of agricultural produce, evaluating Chinese responses to AMR is critical to understanding the efficacy of the global response. Drawing on knowledge of both Chinese politics and health security, this article analyzes how Chinese actors have responded to the threat in the public and animal health sectors as well as the domestic and international implications of these responses. Based on interviews with key Chinese and international officials, scientists, and public health specialists, as well as farmers and consumers, we argue that the securitization of AMR in China is currently more concerned with domestic policy and resource competition than with addressing the existential health threat. Without a greater alignment of AMR strategies within China, macrosecuritizing efforts to address the threat globally cannot succeed.
Asthma Management Responsibility, Control, and Quality of Life Among Emerging Adolescents
Authors: Netz Mallory , Fedele David A , Sweenie Rachel , Baker Dawn , Light Michael , McQuaid Elizabeth L
Published: August 2019

Objective

To examine how asthma control is related to the association between the division of responsibility for asthma management and asthma-related quality of life among early adolescents.

Methods

Forty-nine youth aged 10–15 years (Mage = 12.25, 57.1% female) with a physician-verified asthma diagnosis completed the Standardized Pediatric Asthma Quality of Life Questionnaire (PAQLQ) and Asthma Control Test (ACT). Youth and their caregivers also completed the Asthma Responsibility Questionnaire (ARQ). Higher ACT scores indicate better asthma control.

Results

There was a significant difference in ARQ scores between youth and caregivers (p < .001, d = .94). Youth reported sharing equal responsibility for asthma management with caregivers, while caregivers reported having more responsibility relative to youth. Greater youth-reported ARQ (p = .004) and greater ACT scores (p < .001) were associated with higher PAQLQ scores. ACT scores moderated the effect of youth-reported ARQ on PAQLQ scores (p = .043). For youth with lower ACT scores, higher youth-reported responsibility was associated with higher PAQLQ scores; while for youth with higher ACT scores, PAQLQ scores were high regardless of perceived responsibility. The interaction between caregiver ARQ scores and ACT scores was not significant.

Conclusion

This study suggests youth and caregivers report discrepant ARQ for asthma management tasks. Responsibility and level of asthma control are important factors for PAQLQ, with results indicating that fostering responsibility is an important factor, even among youth with poorly controlled asthma. Findings suggest that healthcare providers should assess family responsibility and help caregivers support adolescents in developing asthma management skills.
Gatekeeping and our moral fabric: Has social capital deterioration vanquished professional oversight?
Authors: Bierman Leonard , Brymer Rhett A , Dust Scott B , Hwang Hyunseok
Published: August 2019

Social capital deterioration in the USA, and indeed throughout the world, has had considerable impact on professional service firms (PSFs). Governmental entities at various levels have enacted new laws and regulations (e.g. the Sarbanes Oxley and Dodd-Frank Acts in the USA) to help ameliorate this situation, but to relatively little avail. Traditional gatekeeping functions of PSFs seem to be deteriorating. Is there hope for the future? This article addresses that issue in the context of work by drawing on the insight and research of Robert Putnam and John Coffee and encouraging advancement of multiple agency theory and governance for today’s world.
Added value of loop-mediated isothermal amplification technology (LAMP) in real life for the diagnosis of malaria in travellers
Authors: Burdino Elisa , Calleri Guido , Ghisetti Valeria
Published: August 2019

Malaria diagnosis in non-endemic countries is questioned by lack of experience and low levels of parasite densities. Loop-mediated isothermal amplification (LAMP) is aimed at simplifying these challenges. In a prospective evaluation over a 2-year period, LAMP significantly simplified malaria identification in 478 febrile travellers and can be considered the primary diagnostic test in this setting.
Severe dengue in travellers: pathogenesis, risk and clinical management
Authors: Halstead Scott , Wilder-Smith Annelies
Published: August 2019

Rationale for review

Dengue is a frequent cause of febrile illness among travellers and has overtaken malaria as the leading cause of febrile illness for those traveling to Southeast Asia. The purpose is to review the risk of dengue and severe dengue in travellers with a particular focus on the pathogenesis and clinical management of severe dengue.

Risk, pathogenesis and clinical management

The risk of travel-acquired dengue depends on destination, season and duration of travel and activities during travel. Seroconversion rates reported in travellers, therefore, vary between <1% and >20%. The most common life-threatening clinical response to dengue infection is the dengue vascular permeability syndrome, epidemiologically linked to secondary infection, but can also occur in primary infection. Tertiary and quaternary infections are usually associated with mild or no disease. Antibody-dependent enhancement, viral factors, age, host factors and clinical experience of the managing physician modulate the risk of progressing to severe dengue. The relative risk of severe dengue in secondary versus primary infection ranges from 2 to 7. The absolute risk of severe dengue in children in highly endemic areas is ~0.1% per year for primary infections and 0.4% for secondary infections. About 2–4% of secondary infections lead to severe dengue. Severe dengue and death are both relatively rare in general travellers but more frequently in those visiting friends and relatives. Clinical management of severe dengue depends on judicious use of fluid rehydration.

Conclusions

Although dengue is a frequent cause of travel illness, severe dengue and deaths are rare. Nevertheless, dengue infections can interrupt travel and lead to evacuation and major out-of-pocket costs. Dengue is more frequent than many other travel-related vaccine preventable diseases, such as hepatitis A, hepatitis B, rabies, Japanese encephalitis and yellow fever, indicating a need for a dengue vaccine for travellers.
John Berryman’s Last Prayers
Authors: McGowan Philip
Published: August 2019

This article examines John Berryman’s last two poetry collections, Love & Fame (1970) and Delusions, etc. (1972) as the poetic articulations of Berryman’s intense scholarly engagement with philosophical and theological discourse. In eschewing confessional readings of his work, the article rehabilitates the term ‘confession’ as Berryman understood it: not as part of recurrent and reductive analyses of the Middle Generation but, rather, as a doctrinal node within Berryman’s theological conceptions of selfhood in relation to God and the role of prayer. In addition, this article connects Berryman's late work to theological frameworks beyond Christianity, principally to the work of S�ren Kierkegaard as well as to aspects of Jewish faith, both of which were enduring interests for Berryman.
Violence and the Romance of Community: Darkness and Enlightenment in Patrick Friesen’s The Shunning
Authors: Kennel Maxwell
Published: August 2019

This article examines one literary expression of the ambiguities of violence in community life through a reading of Patrick Friesen’s The Shunning. By looking to the ways in which the social bonds of community identity are achieved, maintained, and challenged within the ostensibly nonviolent community of Old Colony Russian Mennonites that Friesen’s work portrays, this study focuses on how confluences of community, power, and violence are represented in literary form. Using tools provided by Miranda Joseph’s Against the Romance of Community and Michel Foucault’s critique of Enlightenment blackmail, the following study brings aspects of Mennonite transgressive literature into conversation with critical theory and interprets the portrayal of community discipline in The Shunning within the broader context of the contested relationships between the Enlightenment, modernity, and postmodernity.
Ontology-based analysis of the large collection of historical Hebrew manuscripts
Authors: Zhitomirsky-Geffet Maayan , Prebor Gila , Miller Isaac
Published: August 2019

In this paper, we present a new semi-automatic methodology for construction of event-based ontology from the library catalogue of the largest collection in the world of metadata records of historical Hebrew manuscripts. Based on the constructed ontology, we developed and implemented a new framework for catalogue data enrichment, correction, and its systematic quantitative analysis. Finally, we demonstrate the results of the proposed large-scale analysis of three most prominent event types in the corpus, as well as a few cross-event relations and trends.
Adversative versus concessive while-clauses in native and learner English texts: A corpus-based systemic functional description
Authors: Zhang Yan
Published: August 2019

Despite the commonly reported underuse of linking adverbials of contrast and concession (such as yet, nevertheless) by English as a Foreign Language (EFL) learners in writing, relatively little is known about the use of structural conjunctions in this regard. The present work uses a corpus approach to investigate the use of while, a polysemous conjunction of contrast and concession, in the writing of Chinese EFL learners as compared with their British native-speaker counterparts. The analysis of while-clauses is informed by clause-complexing and textual descriptions of clause in Systemic Functional Linguistics (Halliday and Matthiessen, 2013). Preference for initial concessive while-clauses by native-speaker students was found, in sharp contrast to the dominant use of final adversative while-clauses by Chinese EFL learners. Analysis of the native-speaker data revealed that initial concessive while-clause is characterized by equivalence or relatedness of topical themes of while-clause and its main clause, confirming the discourse-organizing function of thematic hypotactic clauses. In addition, the pattern of non-human subjects and low-value modal operators (e.g. While this … may …) associated dominantly and exclusively with initial concessive while-clauses in the native corpus serves further evidence of distinctive features of concessive while-clauses. This study adds to a growing body of literature on the SFL approach to second language writing and is among the first to combine corpus-based methodologies and SFL theoretical framework to analyze logico-semantic relations. The study concludes with some pedagogical implications for teaching adversative and concessive while-clauses to EFL learners.
Sample statistics as convincing evidence: a tax fraud case†
Authors: Lillestøl Jostein
Published: August 2019

This work deals with the analysis of data used by tax officials to support their claim of tax fraud at a pizzeria. The possibilities of embezzlement under study are overreporting of takeaway sales and underreporting of cash payments. Standard methods based on normal assumptions and models based on Gamma assumptions are contrasted. Criteria for the choice of method in practice are discussed, among them, how easy the method is to understand, justify and communicate to the parties. Some dilemmas present itself: the choice of statistical method, its role in building the evidence, the choice of risk factor, the application of legal principles like ‘clear and convincing evidence’ and ‘beyond reasonable doubt’. The insights gained may be useful for both tax officials and expert witnesses, as well as defenders of the taxpayer. A detailed exposition is given, both from the frequentist and Bayesian position, in order to prepare for the various statistical arguments that may be used by the parties. The presented Gamma approach may be applied to any business dealing with ratios of aggregated sales.
Removing Harmful Options: The Law and Ethics of International Commercial Surrogacy
Authors: Hodson Nathan , Townley Lynne , Earp Brian D
Published: August 2019

Focusing on the UK as a case study, this article argues that having the choice to enter into an international commercial surrogacy arrangement can be harmful, but that neither legalisation nor punitive restriction offers an adequate way to reduce this risk. Whether or not having certain options can harm individuals is central to current debates about the sale of organs. We assess and apply the arguments from that debate to international commercial surrogacy, showing that simply having the option to enter into a commercial surrogacy arrangement can harm potential vendors individually and collectively, particularly given its sexed dimension. We reject the argument that legalizing commercial surrogacy in the UK could reduce international exploitation. We also find that a punitive approach towards intended parents utilizing commercial rather than altruistic services is inappropriate. Drawing on challenges in the regulation of forced marriage and female genital cutting, we propose that international collaboration towards control of commercial surrogacy is a better strategy for preserving the delicate balancing of surrogate mothers’ protection and children’s welfare in UK law.
New β Cep pulsators discovered with K2 space photometry
Authors: Burssens S , Bowman D M , Aerts C , Pedersen M G , Moravveji E , Buysschaert B
Published: August 2019

We present the discovery of three new β Cep pulsators, three new pulsators with frequency groupings, and frequency patterns in a B3Ib star, all of which show pulsations with frequencies as high as about 17 d−1, with K2 space mission photometry. Based on a Fourier analysis and iterative pre-whitening, we present a classification and evaluate the potential for asteroseismic modelling. We include the lists of pulsation frequencies for three new β Cep pulsators, CD-28 12286, CD-27 10876, LS 3978, and additional pulsation mode frequencies for the known β Cep pulsator HD 164741. In addition, we characterize the regular frequency spacing found in the new pulsator HD 169173, and discuss its origin. We place the newly discovered variables in a colour–magnitude diagram using parallaxes from GaiaDR2 (second data release), showcasing their approximate location in the massive star domain. The identified frequency lists of these multiperiodic pulsators are a good starting point for future forward seismic modelling, after identification of at least one pulsation frequency from high-resolution time-series spectroscopy and/or multicolour photometry.
Dark Energy Survey Year 1 results: constraints on intrinsic alignments and their colour dependence from galaxy clustering and weak lensing
Authors: Samuroff S , Blazek J , Troxel M A , MacCrann N , Krause E , Leonard C D , Prat J , Gruen D , Dodelson S , Eifler T F , Gatti M , Hartley W G , Hoyle B , Larsen P , Zuntz J , Abbott T M C , Allam S , Annis J , Bernstein G M , Bertin E , Bridle S L , Brooks D , Carnero Rosell A , Carrasco Kind M , Carretero J , Castander F J , Cunha C E , da Costa L N , Davis C , De Vicente J , DePoy D L , Desai S , Diehl H T , Dietrich J P , Doel P , Flaugher B , Fosalba P , Frieman J , García-Bellido J , Gaztanaga E , Gerdes D W , Gruendl R A , Gschwend J , Gutierrez G , Hollowood D L , Honscheid K , James D J , Kuehn K , Kuropatkin N , Lima M , Maia M A G , March M , Marshall J L , Martini P , Melchior P , Menanteau F , Miller C J , Miquel R , Ogando R L C , Plazas A A , Sanchez E , Scarpine V , Schindler R , Schubnell M , Serrano S , Sevilla-Noarbe I , Sheldon E , Smith M , Sobreira F , Suchyta E , Tarle G , Thomas D , Vikram V ,   (DES Collaboration)
Published: August 2019

We perform a joint analysis of intrinsic alignments and cosmology using tomographic weak lensing, galaxy clustering, and galaxy–galaxy lensing measurements from Year 1 (Y1) of the Dark Energy Survey. We define early- and late-type subsamples, which are found to pass a series of systematics tests, including for spurious photometric redshift error and point spread function correlations. We analyse these split data alongside the fiducial mixed Y1 sample using a range of intrinsic alignment models. In a fiducial non-linear alignment model analysis, assuming a flat Λ cold dark matter cosmology, we find a significant difference in intrinsic alignment amplitude, with early-type galaxies favouring $A_\mathrm{IA} = 2.38^{+0.32}_{-0.31}$ and late-type galaxies consistent with no intrinsic alignments at $0.05^{+0.10}_{-0.09}$. The analysis is repeated using a number of extended model spaces, including a physically motivated model that includes both tidal torquing and tidal alignment mechanisms. In multiprobe likelihood chains in which cosmology, intrinsic alignments in both galaxy samples and all other relevant systematics are varied simultaneously, we find the tidal alignment and tidal torquing parts of the intrinsic alignment signal have amplitudes $A_1 = 2.66 ^{+0.67}_{-0.66}$, $A_2=-2.94^{+1.94}_{-1.83}$, respectively, for early-type galaxies and $A_1 = 0.62 ^{+0.41}_{-0.41}$, $A_2 = -2.26^{+1.30}_{-1.16}$ for late-type galaxies. In the full (mixed) Y1 sample the best constraints are $A_1 = 0.70 ^{+0.41}_{-0.38}$, $A_2 = -1.36 ^{+1.08}_{-1.41}$. For all galaxy splits and IA models considered, we report cosmological parameter constraints consistent with the results of the main DES Y1 cosmic shear and multiprobe cosmology papers.
Galaxy structure with strong gravitational lensing: decomposing the internal mass distribution of massive elliptical galaxies
Authors: Nightingale James W , Massey Richard J , Harvey David R , Cooper Andrew P , Etherington Amy , Tam Sut-Ieng , Hayes Richard G
Published: August 2019

We investigate how strong gravitational lensing can test contemporary models of massive elliptical (ME) galaxy formation, by combining a traditional decomposition of their visible stellar distribution with a lensing analysis of their mass distribution. As a proof of concept, we study a sample of three ME lenses, observing that all are composed of two distinct baryonic structures, a ‘red’ central bulge surrounded by an extended envelope of stellar material. Whilst these two components look photometrically similar, their distinct lensing effects permit a clean decomposition of their mass structure. This allows us to infer two key pieces of information about each lens galaxy: (i) the stellar mass distribution (without invoking stellar populations models) and (ii) the inner dark matter halo mass. We argue that these two measurements are crucial to testing models of ME formation, as the stellar mass profile provides a diagnostic of baryonic accretion and feedback whilst the dark matter mass places each galaxy in the context of LCDM large scale structure formation. We also detect large rotational offsets between the two stellar components and a lopsidedness in their outer mass distributions, which hold further information on the evolution of each ME. Finally, we discuss how this approach can be extended to galaxies of all Hubble types and what implication our results have for studies of strong gravitational lensing.
A new sample of X-ray selected Swift/SDSS faint blazars and blazar candidates
Authors: Turriziani Sara , Fraga B , Giommi P
Published: August 2019

Our present knowledge of the properties of blazars mostly comes from small samples of bright objects, especially regarding studies on their cosmological evolution. Statistically well defined and completely identified samples of faint blazars are very difficult to obtain. We present a new X-ray selected sample of 62 blazars and blazar candidates reaching deep X-ray fluxes. We relied on the availability of large catalogs of astronomical objects combined with on-line services offering simple access to finding charts and magnitude estimates. We built the sample cross-matching X-ray sources in the Swift Serendipitous Survey in deep XRT GRB Fields catalog with data from deep radio and optical surveys. Our sample can probe populations of sources 10 times weaker in the X-ray flux with respect previous studies, thus allowing for a more detailed comparison between data and simulated counts. We use the sample to calculate the radio and X-ray LogN-LogS of blazars down to fluxes at least one order of magnitude fainter than previous studies. We show that, considering that our sample may be somewhat contaminated by sources other than blazars, we are in agreement with previous observational and theoretical estimations.
Constraining primordial non-Gaussianity using two galaxy surveys and CMB lensing
Authors: Ballardini Mario , Matthewson William L , Maartens Roy
Published: August 2019

Next-generation galaxy surveys will be able to measure perturbations on scales beyond the equality scale. On these ultra-large scales, primordial non-Gaussianity leaves signatures that can shed light on the mechanism by which perturbations in the early Universe are generated. We perform a forecast analysis for constraining local type non-Gaussianity and its two-parameter extension with a simple scale-dependence. We combine different clustering measurements from future galaxy surveys – a 21cm intensity mapping survey and two photometric galaxy surveys – via the multitracer approach. Furthermore we then include cosmic microwave background (CMB) lensing from a CMB Stage 4 experiment in the multitracer, which can improve the constraints on bias parameters. We forecast σ(fNL) ≃ 0.9 (1.4) by combining SKA1, a Euclid-like (LSST-like) survey, and CMB Stage 4 lensing. With CMB lensing, the precision on fNL improves by up to a factor of 2, showing that a joint analysis is important. In the case with running of fNL, our results show that the combination of upcoming cosmological surveys could achieve σ(nNL) ≃ 0.12 (0.22) on the running index.
The beamed jet and quasar core of the distant blazar 4C 71.07
Authors: Raiteri C M , Villata M , Carnerero M I , Acosta-Pulido J A , Mirzaqulov D O , Larionov V M , Romano P , Vercellone S , Agudo I , Arkharov A A , Bach U , Bachev R , Baitieri S , Borman G A , Boschin W , Bozhilov V , Butuzova M S , Calcidese P , Carosati D , Casadio C , Chen W-P , Damljanovic G , Di Paola A , Doroshenko V T , Efimova N V , Ehgamberdiev Sh A , Giroletti M , Gómez J L , Grishina T S , Ibryamov S , Jermak H , Jorstad S G , Kimeridze G N , Klimanov S A , Kopatskaya E N , Kurtanidze O M , Kurtanidze S O , Lähteenmäki A , Larionova E G , Marscher A P , Mihov B , Minev M , Molina S N , Moody J W , Morozova D A , Nazarov S V , Nikiforova A A , Nikolashvili M G , Ovcharov E , Peneva S , Righini S , Rizzi N , Sadun A C , Samal M R , Savchenko S S , Semkov E , Sigua L A , Slavcheva-Mihova L , Steele I A , Strigachev A , Tornikoski M , Troitskaya Yu V , Troitsky I S , Vince O
Published: August 2019

The object 4C 71.07 is a high-redshift blazar whose spectral energy distribution shows a prominent big blue bump and a strong Compton dominance. We present the results of a 2-yr multiwavelength campaign led by the Whole Earth Blazar Telescope (WEBT) to study both the quasar core and the beamed jet of this source. The WEBT data are complemented by ultraviolet and X-ray data from Swift, and by γ-ray data by Fermi. The big blue bump is modelled by using optical and near-infrared mean spectra obtained during the campaign, together with optical and ultraviolet quasar templates. We give prescriptions to correct the source photometry in the various bands for the thermal contribution, in order to derive the non-thermal jet flux. The role of the intergalactic medium absorption is analysed in both the ultraviolet and X-ray bands. We provide opacity values to deabsorb ultraviolet data, and derive a best-guess value for the hydrogen column density of $N_{\rm H}^{\rm best}=6.3 \times 10^{20} \rm \, cm^{-2}$ through the analysis of X-ray spectra. We estimate the disc and jet bolometric luminosities, accretion rate, and black hole mass. Light curves do not show persistent correlations among flux changes at different frequencies. We study the polarimetric behaviour and find no correlation between polarization degree and flux, even when correcting for the dilution effect of the big blue bump. Similarly, wide rotations of the electric vector polarization angle do not seem to be connected with the source activity.
On the role of supermassive black holes in quenching star formation in local central galaxies
Authors: Arora Nikhil , Fossati Matteo , Fontanot Fabio , Hirschmann Michaela , Wilman David J
Published: August 2019

We analyse the role of AGN feedback in quenching star formation for massive, central galaxies in the local Universe. In particular, we compare the prediction of two semi-analytic models (l-galaxies  and sage) featuring different schemes for AGN feedback, with the SDSS DR7 taking advantage of a novel technique for identifying central galaxies in an observational data set. This enables us to study the correlation between the model passive fractions, which is predicted to be suppressed by feedback from an AGN, and the observed passive fractions in an observationally motivated parameter space. While the passive fractions for observed central galaxies show a good correlation with stellar mass and bulge mass, passive fractions in l-galaxies  correlate with the halo and black hole mass. For sage, the passive fraction correlate with the bulge mass as well. Among the two models, sage has a smaller scatter in the black hole–bulge mass $({M_{\rm BH}-M_{\rm Bulge}})$ relation and a slope that agrees better with the most recent observations at z ∼ 0. Despite the more realistic prescription of radio-mode feedback in sage, there are still tensions left with the observed passive fractions and the distribution of quenched galaxies. These tensions may be due to the treatment of galaxies living in non-resolved substructures and the resulting higher merger rates that could bring cold gas which is available for star formation.
Low-frequency X-ray timing with Gaussian processes and reverberation in the radio-loud AGN 3C 120
Authors: Wilkins D R
Published: August 2019

A framework is developed to perform Fourier-domain timing analysis on X-ray light curves with gaps, employing Gaussian processes to model the probability distribution underlying the observed time series from which continuous samples can be drawn. A technique is developed to measure X-ray reverberation from the inner regions of accretion discs around black holes in the low-frequency components of the variability, on time-scales longer than can be probed employing standard Fourier techniques. This enables X-ray reverberation experiments to be performed using data from satellites in low-Earth orbit such as NICER, NuSTAR, and the proposed X-ray timing mission STROBE-X, and enables long time-scale reverberation around higher mass active galactic nuclei (AGNs) to be measured by combining observations. Gaussian processes are applied to observations of the broad line radio galaxy 3C 120 spanning two orbits with XMM–Newton to measure the relative time lags of successive X-ray energy bands. The lag–energy spectrum between 5 × 10−6 and 3 × 10−5 Hz, estimated using Gaussian processes, reveals X-ray reverberation from the inner accretion disc for the first time in this radio-loud AGN. Time lags in the relativistically broadened iron K line are significantly detected. The core of the line lags behind the continuum by (3800 ± 1500) s, suggesting a scale height of the corona of (13 ± 8) rg above the disc. The ability to compare the structure of coronae in radio-loud AGNs to their radio-quiet counterparts will yield important insight into the mechanisms by which black holes are able to launch jets.
The ultra-diffuse dwarf galaxies NGC 1052-DF2 and 1052-DF4 are in conflict with standard cosmology
Authors: Haslbauer Moritz , Banik Indranil , Kroupa Pavel , Grishunin Konstantin
Published: August 2019

Recently van Dokkum et al. reported that the galaxy NGC 1052-DF2 (DF2) lacks dark matter if located at 20 Mpc from Earth. In contrast, DF2 is a dark-matter-dominated dwarf galaxy with a normal globular cluster population if it has a much shorter distance near 10 Mpc. However, DF2 then has a high peculiar velocity wrt. the cosmic microwave background of 886 $\rm {km\, s^{-1}}$, which differs from that of the Local Group (LG) velocity vector by 1298 $\rm {km\, s^{-1}}$ with an angle of $117 \, ^{\circ }$. Taking into account the dynamical M/L ratio, the stellar mass, half-light radius, peculiar velocity, motion relative to the LG, and the luminosities of the globular clusters, we show that the probability of finding DF2-like galaxies in the lambda cold dark matter (ΛCDM) TNG100-1 simulation is at most 1.0 × 10−4 at 11.5 Mpc and is 4.8 × 10−7 at 20.0 Mpc. At 11.5 Mpc, the peculiar velocity is in significant tension in the TNG100-1, TNG300-1, and Millennium simulations, but naturally in a Milgromian cosmology. At 20.0 Mpc, the unusual globular cluster population would challenge any cosmological model. Estimating that precise measurements of the internal velocity dispersion, stellar mass, and distance exist for 100 galaxies, DF2 is in 2.6σ (11.5 Mpc) and 4.1σ (20.0 Mpc) tension with standard cosmology. Adopting the former distance for DF2 and assuming that NGC 1052-DF4 is at 20.0 Mpc, the existence of both is in tension at ≥4.8σ with the ΛCDM model. If both galaxies are at 20.0 Mpc the ΛCDM cosmology has to be rejected by ≥5.8σ.
A multispectral analysis of the northeastern shell of IC 443
Authors: Alarie Alexandre , Drissen Laurent
Published: August 2019

We have carried out optical observations of the northeastern part of the supernova remnant IC 443 using the Canada–France–Hawaii Telescope imaging spectrograph SITELLE. The observations consist of three multispectral cubes covering an 11′ × 11′ area allowing the investigation of both the spatial and spectral variation of nine emission lines:  [O ii] λλ3726 + 3729,  [O iii] λλ4959, 5007,  H β,  H α,  [N ii] λλ6548, 6583, and  [S ii] λλ6716, 6731. Extinction measurement from the  H α/ H β shows significant variation across the observed region with E(B − V) = 0.8–1.1. Electron density measurements using  [S ii] lines indicate densities ranging from 100 up to 2500  cm−3. Models computed with the shock modelling code mappings are presented and compared with the observations. A combination of complete shock model and truncated ones is required in order to explain the observed spectrum. The shock velocities found in IC 443 are between 20 and 150  km s−1, with 75  km s−1 being the most prominent velocity. The pre-shock number density varies from 20 to 60  cm−3. A single set of abundances close to solar values combined with varying shock parameters (shock velocity, pre-shock density, and shock age) is sufficient to explain the great variation of line intensities observed in IC 443. Despite the relatively modest spectral resolution of the data (R ∼ 1500 at  H α), we clearly separate the red and blue velocity components of the expanding nebula, which show significant morphological differences.
Oxygen abundance and the N/C versus N/O relation for AFG supergiants and bright giants
Authors: Lyubimkov L S , Korotin S A , Lambert D L
Published: August 2019

Non-LTE analysis (where LTE is local thermodynamic equilibrium) of the oxygen abundances for 51 Galactic A-, F- and G-type supergiants and bright giants is performed. In contrast with carbon and nitrogen, oxygen does not show any significant systematic anomalies in its abundances log ε(O). There is no marked difference from the initial oxygen abundance, within the errors, for the log ε(O) determination across the Teff interval from 4500–8500 K and the $\log \, g$ interval from 1.2–2.9 dex. This result agrees well with theoretical predictions for stellar models with rotation. With our new data for oxygen and our earlier non-LTE determinations of the N and C abundances for stars from the same sample, we constructed the [N/C] versus [N/O] relation for 17 stars. This relation is known to be a sensitive indicator of stellar evolution. A pronounced correlation between [N/C] versus [N/O] is found; the observed [N/C] increase from 0 to 1.6 dex is accompanied by a [N/O] increase from 0 to 0.9 dex. When comparing the observed [N/C] versus [N/O] relation with the theoretical one, we show that this relation reflects a strong dependence of the evolutionary changes in CNO abundances on the initial rotation velocities of stars. Given that the initial rotational velocities of these stars are expected to satisfy V0 < 150 km s−1, it is found that they are mostly post-first-dredge-up (post-FDU) objects. It is important that such initial velocities V0 are typical for about 80 per cent of the stars in question (i.e. stars with masses 4–19 M$\odot$). A constancy of the total C+N+O abundance during stellar evolution is confirmed. The mean value of log ε(C+N + O) = 8.97 ± 0.08 found for AFG supergiants and bright giants seems to be very close to the initial values of 8.92 (the Sun) or 8.94 (unevolved B-type main-sequence stars).
Variable jet Lorentz factors can explain soft self-absorbed radio spectra of accreting black holes
Authors: Zdziarski Andrzej A
Published: August 2019

We study the effect of variable jet bulk Lorentz factors, i.e. either jet acceleration or deceleration, on partially synchrotron self-absorbed radio spectra from cores of radio-loud active galactic nuclei and black hole binaries in the hard state. In about a half of quasars and radio galaxies, their core radio spectra are observed to be soft, i.e. have the spectral index of α < 0. If they are emitted by jets with constant Lorentz factors, that softness implies deposition of large amounts of energy at large distances from the centre. We show here that such soft spectra can be explained without that energetic requirement by emission of jets with the Doppler factor increasing with the distance. This can happen for either jet acceleration or deceleration, depending on the jet viewing angle. We find our model can explain the quiescent radio to X-ray spectra of the BL Lac objects Mrk 421 and Mrk 501.