bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling the epidemic dynamics and control of COVID‐19 outbreak in China
Authors: Zhao Shilei , Chen Hua
Published: March 2020

Background

The coronavirus disease 2019 (COVID‐19) is rapidly spreading in China and more than 30 countries over last two months. COVID‐19 has multiple characteristics distinct from other infectious diseases, including high infectivity during incubation, time delay between real dynamics and daily observed number of confirmed cases, and the intervention effects of implemented quarantine and control measures.

Methods

We develop a Susceptible, Un‐quanrantined infected, Quarantined infected, Confirmed infected (SUQC) model to characterize the dynamics of COVID‐19 and explicitly parameterize the intervention effects of control measures, which is more suitable for analysis than other existing epidemic models.

Results

The SUQC model is applied to the daily released data of the confirmed infections to analyze the outbreak of COVID‐19 in Wuhan, Hubei (excluding Wuhan), China (excluding Hubei) and four first‐tier cities of China. We found that, before January 30, 2020, all these regions except Beijing had a reproductive number R > 1, and after January 30, all regions had a reproductive number R < 1, indicating that the quarantine and control measures are effective in preventing the spread of COVID‐19. The confirmation rate of Wuhan estimated by our model is 0.0643, substantially lower than that of Hubei excluding Wuhan (0.1914), and that of China excluding Hubei (0.2189), but it jumps to 0.3229 after February 12 when clinical evidence was adopted in new diagnosis guidelines. The number of un‐quarantined infected cases in Wuhan on February 12, 2020 is estimated to be 3,509 and declines to 334 on February 21, 2020. After fitting the model with data as of February 21, 2020, we predict that the end time of COVID‐19 in Wuhan and Hubei is around late March, around mid March for China excluding Hubei, and before early March 2020 for the four tier‐one cities. A total of 80,511 individuals are estimated to be infected in China, among which 49,510 are from Wuhan, 17,679 from Hubei (excluding Wuhan), and the rest 13,322 from other regions of China (excluding Hubei). Note that the estimates are from a deterministic ODE model and should be interpreted with some uncertainty.

Conclusions

We suggest that rigorous quarantine and control measures should be kept before early March in Beijing, Shanghai, Guangzhou and Shenzhen, and before late March in Hubei. The model can also be useful to predict the trend of epidemic and provide quantitative guide for other countries at high risk of outbreak, such as South Korea, Japan, Italy and Iran.
Trace and Rare Earth Element Distribution and Mobility During Diagenetic Alteration of Volcanic Ash to Bentonite in Eastern Iranian Bentonite Deposits
Authors: Namayandeh Alireza , Modabberi Soroush , López-Galindo Alberto
Published: March 2020

The chemical composition of the source magma along with the physiochemical conditions of the depositional environment are the main controlling factors in determining the behavior and mobility of trace elements and rare earth elements (REEs) during the transformation of volcanic ash to bentonite. The purpose of the present study was to determine the distribution pattern and mobility of trace elements and REEs in several bentonite deposits formed by diagenetic alteration of volcanic ash in shallow alkaline water in eastern Iran. Using geochemical and statistical data, the degree of weathering in the parent rocks and the distribution and mobility of trace elements and REEs during the alteration process at seven deposits (Chah-Taleb, Chah-Keshmir, Chah-Golestan, Chah-Pirouz, Gholeh-Gelia, Kharman-Sar, and Khal-Kooh) were studied. None of the parent rocks showed an advanced degree of depositional reworking and, therefore, their chemical composition is representative of the volcanic ash from which the bentonites were formed. In the chondrite-normalized REE patterns of both parent rocks and bentonites, the light rare earth elements (LREEs) were found to be enriched relative to the heavy rare earth elements (HREEs). The variation in δEu and δCe values suggested a high-temperature (<200°C), suboxic, aquatic environment in which the conversion of volcanic ash to bentonite occurred. In the bivariate correlation analysis, Si showed a strong inverse relationship with Al and LREEs, while large ion lithophile elements (LILEs), high field strength elements (HFSEs), HREEs, and LREEs displayed a positive correlation between the elements of their respective groups. The R2 values in the binary diagram of potential immobile elements against Al suggest a qualitative classification in which Ti, Gd, Ga, Pr, Tb, Nd, Sm, Ce, and Nb are considered immobile, and U, Dy, In, Sc, Hf, Zr, La, and Eu are considered to have had poor mobility during formation of the Eastern Iranian bentonite deposits.
Plasma RANTES level is correlated with cardio‐cerebral atherosclerosis burden in patients with ischemic cerebrovascular disease
Authors: Kong Qi , Ma Xin , Lyu Jun‐Xuan , Wang Chen , Du Xiang‐Ying , Guan Yun‐Qian
Published: March 2020

Background

Regulated upon activation, normal T‐cell expressed, and secreted (RANTES) is a chemokine actively involved in the initiation and progression of atherosclerosis (AS), which is the major cause of ischemic cerebrovascular disease (ICVD). This study aimed to determine the associations between circulating RANTES level and overall AS conditions of cardiac and cerebral vessel beds in patients with ICVD.

Methods

Patients with ICVD admitted to the department of neurology of Xuanwu Hospital from April 1, 2019 to June 30, 2019 were prospectively enrolled in the study. Plasma RANTES level was measured by enzyme‐linked immunosorbent assay to represent the circulating RANTES level. The integrated AS burden of the cervicocephalic and coronary arteries was examined using computed tomography angiography and reflected by “cardio‐cerebral AS burden (CCAB)” as a continuous variable. Then, the relationship of plasma RANTES level and CCAB in patients with ICVD was analyzed by correlation analyses and general linear models.

Results

A total of 40 patients with ICVD were included in the study. There was a significant positive correlation between CCAB and plasma RANTES level in ICVD (r = 0.786, P < 0.001), independent of age, sex, acute or chronic phase of ICVD, and mono or dual antiplatelet therapy (adjusted B for ln RANTES, 12.063; 95% confidence interval, 7.572–16.533). The association of plasma RANTES level with AS conditions (burden, severity, and extent) in single cardiac or cerebral vessel bed was similar to that with CCAB, but the correlation coefficient for CCAB was higher (increment ranged from 0.126 to 0.397).

Conclusions

Plasma RANTES level was an independent indicator for the integrated AS burden of the cervicocephalic and coronary arteries in ICVD. Comprehensive evaluation of AS conditions using the novel continuous index CCAB might be important in revealing the systematic relationship between circulating RANTES and AS in patients with ICVD.
Association Between Lifelong Premature Ejaculation and Polymorphism of Tryptophan Hydroxylase 2 Gene in the Han Population
Authors: Fu Xu , Zhang Xiansheng , Jiang Tao , Huang Yuanyuan , Cheng Peng , Tang Dongdong , Gao Jingjing , Du JunHua
Published: March 2020

Introduction

Premature ejaculation (PE) is widely regarded as one of the most common sexual dysfunctions in men. The neurobiogenesis of PE is complex and involves the serotoninergic (5-HT) system.

Aim

In this study, we investigated whether polymorphisms in the tryptophan hydroxylase 2 (TPH2) gene were associated with lifelong PE (LPE).

Methods

A total of 121 men diagnosed with LPE were recruited from our outpatient clinics and 94 healthy controls from the health examination center. Intravaginal ejaculation latency time (IELT) was measured using a stopwatch. The PE diagnostic tool (PEDT) data were collected at the same time. All subjects with LPE and healthy controls were genotyped for polymorphisms in the TPH2 gene. Allele and genotype frequencies of single-nucleotide polymorphisms (SNPs) were compared between the patients and controls.

Main Outcome Measure

The main outcome measures are IELT and PEDT to diagnose LPE. The association of LPE with TPH2 gene polymorphisms in these areas was investigated.

Results

The IELT, PEDT scores, and education levels in the LPE group were significantly different from those in the control group. Statistically significant differences were found in the SNPs of SNV019 and rs4290270. The frequencies of the G allele and G/A genotype of SNV019 were significantly higher in the patients with LPE than in the controls (P = .045 and .037, respectively). The A allele and A/A genotype of rs4290270 were more frequent in the patients with LPE than in the controls (P = .037 and .049, respectively). In the dominant model of inheritance, the SNV019 polymorphism in the patients with LPE was significantly different from that in the controls (odds ratio [95% confidence interval] = 2.936 [1.066–8.084], P = .037). In men with LPE, there was no statistically significant association between genotype and median IELT.

Conclusion

The SNPs SNV019 and rs4290270 of the TPH2 gene seemed to be associated with LPE in the Han population. Men with the A allele of SNV019 or the T allele of rs4290270 may be less likely to suffer from LPE.
“Current concepts of mechanical ventilation in neonates” – Part 1
Authors: Chakkarapani Aravanan Anbu , Adappa Roshan , Mohammad Ali Sanoj Karayil , Gupta Samir , Soni Naharmal B. , Chicoine Louis , Hummler Helmut D.
Published: March 2020

Mechanical ventilation is potentially live saving in neonatal patients with respiratory failure. The main purpose of mechanical ventilation is to ensure adequate gas exchange, including delivery of adequate oxygenation and enough ventilation for excretion of CO2. The possibility to measure and deliver small flows and tidal volumes have allowed to develop very sophisticated modes of assisted mechanical ventilation for the most immature neonates, such as volume targeted ventilation, which is used more and more by many clinicians. Use of mechanical ventilation requires a basic understanding of respiratory physiology and pathophysiology of the disease leading to respiratory failure. Understanding pulmonary mechanics, elastic and resistive forces (compliance and resistance), and its influence on the inspiratory and expiratory time constant, and the mechanisms of gas exchange are necessary to choose the best mode of ventilation and adequate ventilator settings to minimize lung injury. Considering the pathophysiology of the disease allows a physiology-based approach and application of these concepts in daily practice for decision making regarding the use of modes and settings of mechanical ventilation, with the ultimate aim of providing adequate gas exchange and minimising lung injury.
Une histoire politique des chiffres de la prison: Conception, production et usages de laStatistique pénitentiaire(1852-1939)
Authors: Génard Elsa , Simioni Melchior
Published: March 2020

Résumés

Produite par l’administration pénitentiaire de façon continue entre 1852 et 1939, laStatistique pénitentiaireest une source fournissant de nombreuses informations sur la situation des prisons. En retraçant l’ensemble de la chaîne d’existence des chiffres de la prison, de leur conception à leur utilisation, cette étude entend mettre en lumière le contraste entre l’importance des moyens que la production de ce document suppose, la diversité des informations qu’il recèle et la faiblesse de ses usages. Pensé initialement comme un outil pour la réforme des prisons, il se présente comme une statistique des établissements pénitentiaires, produite à tous les échelons de l’administration. Alors que les prisons et le crime sont au cœur des débats publics à la fin duxixe siècle, son utilisation en dehors de l’administration apparaît toutefois marginale. Cette discrétion dans les arènes de discussion sur ce sujet révèle un effacement de la statistique des prisons au profit de la statistique judiciaire, plus prestigieuse et plus à même d’alimenter les débats politiques sur la récidive. En 1911, pourtant, un projet de fusion des statistiques judiciaire et pénitentiaire peut apparaître comme une occasion de redonner aux chiffres de la prison une utilité dans la connaissance du crime. Mais l’échec de cette fusion confirme le peu d’intérêt que cette source suscite et s’accompagne d’un appauvrissement conséquent de ses tableaux, avec la suppression des informations sur les individus incarcérés à partir de 1911. Cet article entend ainsi poser la question de l’utilité d’une source qui est apparue peu utile, afin de réinterroger les rapports entre statistique, prison et État.
Hurricane Shutter-Related Injuries Treated in Emergency Departments
Authors: Forrester Mathias B.
Published: March 2020

Objectives:

Injuries may occur when putting up and taking down hurricane (storm) shutters. This study described hurricane shutter-related injuries managed at emergency departments (EDs).

Methods:

Hurricane shutter-related injuries were identified through the National Electronic Injury Surveillance System (NEISS), a database of consumer product-related injuries collected from the EDs of approximately 100 United States hospitals.

Results:

There were 329 hurricane shutter-related injuries during 2001-2017. Thirty-six injuries were reported during October 2005 (Hurricane Wilma), 30 during August 2008 (Tropical Storm Fay), and 103 during September 2017 (Hurricane Irma). Patients were 20 years or older in 90.6% of the cases; 76.3% of the patients were male. The most frequently reported injuries were laceration (48.9%), sprain or strain (15.2%), and fracture (9.4%). Lower extremities (34.0%) were the most commonly affected body part followed by upper extremities (29.5%) and head or neck (17.0%). The patient was treated or examined at the ED and released in 86.6% of the cases.

Conclusions:

Over half of the hurricane shutter-related injuries appeared to occur in association with hurricanes and tropical storms. The most frequently reported injuries were laceration followed by sprain or strain and fracture. The majority of patients were treated or examined at the ED and released.
The effect of β-carotene on the mortality of male smokers is modified by smoking and by vitamins C and E: evidence against a uniform effect of nutrient
Authors: Hemilä Harri
Published: March 2020

A previous analysis of the Alpha-Tocopherol Beta-Carotene (ATBC) Study on male smokers found that β-carotene supplementation increased the risk of pneumonia 4-fold in those who started smoking at the age of ≥21 years and smoked ≥21 cigarettes/d (a subgroup of 7 % of the study population). The present study hypothesised that β-carotene increases mortality in the same subgroup. The ATBC Study (1985–1993) recruited 29 133 Finnish male smokers (≥5 cigarettes/d) aged 50–69 years. Cox regression models were constructed to estimate the effect of β-carotene supplementation in subgroups. β-Carotene increased mortality (risk ratio 1·56; 95 % CI 1·06, 2·3) in those who started to smoke at ≥21 years and smoked ≥21 cigarettes/d. Within this subgroup, there was strong evidence of further heterogeneity. The effect of β-carotene supplementation was further modified by dietary vitamin C intake, fruit and vegetable intake (P= 0·0004), and by vitamin E supplementation (P= 0·011). Thus, harm from β-carotene was not uniform within the study population. Interactions between β-carotene and vitamins C and E were seen only within a subgroup of 7 % of the ATBC participants, and therefore should not be extrapolated to the general population. Heterogeneity of the β-carotene effect on mortality challenges the validity of previous meta-analyses that have pooled many diverse antioxidants for one single estimate of effect using the assumption that a single estimate equally applies to all antioxidants and all people. Trial registration: ClinicalTrials.gov NCT00342992.
#weareone: blood donation, terrorism and dreams of inclusion in Kenya
Authors: Harrington John
Published: March 2020

This article examines responses to the terrorist attack on the Westgate Shopping Centre in Nairobi in September 2013 in order to investigate the role played by blood donation, as an expression of national dreams, in the political imaginary of contemporary Kenya. It considers the symbolic effectiveness of calls for blood donation made by political figures in the aftermath of the attacks. Such calls drew on a tradition of donation drives begun in the early years of independence, which emphasized the modernizing imperative of the new state and the importance of unity, hard work and self-sacrifice in building the nation. However, the reaction to Westgate, including calls for blood donation, also needs to be understood with reference to the response of American and other leaders to equivalent terrorist attacks in more recent years. These elite dreams found resonance among ordinary citizens and blood donation recruiters. But they were also subjected to trenchant critiques that sought to expose the reality of the transfusion system, as well as the inequality and injustice that mark the general healthcare system and Kenyan society as a whole. These shortcomings were also highlighted by mobilization drives organized by Kenya's Somali and Asian communities both before and during the Westgate crisis. The latter are presented by their organizers as a means of overcoming historic exclusion and discrimination.
Mood sensitivity to estradiol predicts depressive symptoms in the menopause transition
Authors: Gordon Jennifer L. , Sander Bethany , Eisenlohr-Moul Tory A. , Sykes Tottenham Laurie
Published: March 2020

Background

The risk for depression markedly rises during the 5–6 years leading up to the cessation of menstruation, known as the menopause transition. Exposure to extreme estradiol levels may help explain this increase but few studies have examined individual sensitivity to estradiol in predicting perimenopausal depression.

Method

The current study recruited 101 perimenopausal women. During Phase 1, we quantified each woman's sensitivity to changes in estradiol using 12 weekly measures of estrone-3-glucuronide (E1G), a urinary metabolite of estradiol, and concurrent depressive symptoms. The weekly cortisol awakening response was measured to examine the hypothalamic-pituitary-adrenal (HPA) axis in mediating mood sensitivity to estradiol. In Phase 2, depressive symptoms and major depression diagnoses were assessed monthly for 9 months. The relationship between Phase 1 E1G sensitivity and Phase 2 depressive symptoms and major depressive episodes was examined. Several baseline characteristics were examined as potential moderators of this relationship.

Results

The within-person correlation between weekly E1G and mood varied greatly from woman to woman, both in strength and direction. Phase 1 E1G mood sensitivity predicted the occurrence of clinically significant depressive symptoms in Phase 2 among certain subsets of women: those without a prior history of depression, reporting a low number of baseline stressful life events, and reporting fewer months since their last menstrual period. HPA axis sensitivity to estradiol fluctuation did not predict Phase 2 outcomes.

Conclusion

Mood sensitivity to estradiol predicts risk for perimenopausal depression, particularly among women who are otherwise at low risk and among those who are early in the transition.
Holistic resource-rational analysis
Authors: Haas Julia , Klein Colin
Published: March 2020

We argue that Lieder and Griffiths’ method for analyzing rational process models cannot capture an important constraint on resource allocation, which is competition between different processes for shared resources (Klein 2018, Biology and Philosophy33:36). We suggest that holistic interactions between processes on at least three different timescales – episodic, developmental, and evolutionary – must be taken into account by a complete resource-bounded explanation.
Heuristics and the naturalistic fallacy
Authors: Kalbach Christopher J.
Published: March 2020

Lieder and Griffith's account of resource-rationality relies heavily on a notion of teleology. In this commentary, I criticize their teleocentric view as being incompatible with evolutionary theory, in which they aim to ground their analysis. As such, to save their view, I argue that they must jettison the notion of teleology, and their teleologically laden conclusions.
Resource-rationality as a normative standard of human rationality
Authors: Colombo Matteo
Published: March 2020

Lieder and Griffiths introduce resource-rational analysis as a methodological device for the empirical study of the mind. But they also suggest resource-rationality serves as a normative standard to reassess the limits and scope of human rationality. Although the methodological status of resource-rational analysis is convincing, its normative status is not.
Resource-rationality beyond individual minds: the case of interactive language use
Authors: Dingemanse Mark
Published: March 2020

Resource-rational approaches offer much promise for understanding human cognition, especially if they can reach beyond the confines of individual minds. Language allows people to transcend individual resource limitations by augmenting computation and enabling distributed cognition. Interactive language use, an environment where social rational agents routinely deal with resource constraints together, offers a natural laboratory to test resource-rationality in the wild.
Uncovering cognitive constraints is the bottleneck in resource-rational analysis
Authors: Dimov Cvetomir
Published: March 2020

A major constraint in resource-rational analysis is cognitive resources. Yet, uncovering the nature of individual components of the human mind has progressed slowly, because even the simplest behavior is a function of most (if not all) of the mind. Accelerating our understanding of the mind's structure requires more efforts in developing cognitive architectures.
Can resources save rationality? “Anti-Bayesian” updating in cognition and perception
Authors: Mandelbaum Eric , Won Isabel , Gross Steven , Firestone Chaz
Published: March 2020

Resource rationality may explain suboptimal patterns of reasoning; but what of “anti-Bayesian” effects where the mind updates in a direction opposite the one it should? We present two phenomena – belief polarization and the size-weight illusion – that are not obviously explained by performance- or resource-based constraints, nor by the authors’ brief discussion of reference repulsion. Can resource rationality accommodate them?
Providing informal care next to paid work: explaining care-giving gratification, burden and stress among older workers
Authors: Grünwald Olga , Damman Marleen , Henkens Kène
Published: March 2020

With an increasing retirement age, more older adults are combining employment with informal care-giving responsibilities. However, little is known about how older workers experience care-giving activities next to their paid jobs. This study aims to fill this gap by examining how the work situation (i.e. working hours, occupational status and perceived access to human resources practices) is associated with feelings of gratification, burden and stress in care-giving. Using data from the NIDI Pension Panel Survey, we study care-giving experiences – in other words, the extent to which care-giving activities are gratifying, burdensome or stressful – of 1,651 Dutch older workers (age 60–65) who provide care at least once per week. Multivariate analyses reveal that the work situation plays an explanatory role next to socio-demographic factors and indicators of the care-giving situation. Working care-givers who feel they have access to phased retirement and organisational health support experience care-giving as relatively less burdensome and stressful. Moreover, those with access to phased retirement experience relatively higher levels of gratification in care-giving. Our findings suggest that the availability of organisational support relates to lower levels of care-giving burden and stress, and to some extent to higher levels of gratification. Organisations thus play an important role in facilitating the combination of work and care-giving obligations in a context of longer working lives.
Commentary: Responsibility-Sensitive Healthcare Funding: Three Responses to Clavien and Hurst’s Critique
Authors: DOUGLAS THOMAS
Published: March 2020

Christine Clavien and Samia Hurst1 (henceforth C-H) make at least three valuable contributions to the literature on responsibility and healthcare. They offer an admirably clear and workable set of criteria for determining a patient's degree of responsibility for her health condition; they deploy those criteria to cast doubt on the view that patients with lifestyle-related conditions are typically significantly responsible for their conditions; and they outline several practical difficulties that would be raised by any attempt to introduce responsibility-sensitive healthcare funding. I am sympathetic to the general thrust of their argument, share—at least tentatively—their policy conclusions, and was persuaded by much of the detail of their argument. However, I do have three critical comments.
Lessons Learned in Developing and Testing a Methotrexate Case Study for Pharmacy Education
Authors: KARWAKI TANYA E. , HAZLET THOMAS K. , WILSON NORTON JENNIFER L.
Published: March 2020

This article describes the development, implementation, and evaluation of a complex methotrexate ethics case used in teaching a Pharmacy Law and Ethics course. Qualitative analysis of student reflective writings provided useful insight into the students’ experience and comfort level with the final ethics case in the course. These data demonstrate a greater student appreciation of different perspectives, the potential for conflict in communicating about such cases, and the importance of patient autonomy. Faculty lessons learned are also described, facilitating adoption of this methotrexate ethics case by other healthcare profession educators.
Moral Compass in the Care of Patients Who Choose Aid in Dying
Authors: BENNAHUM DAVID A.
Published: March 2020

How can an individual’s Moral Compass address the question of whether or not to help a patient to shorten and end his or her life? Moral Compass has been defined as that set of values and experiences that guides each individual’s decisions and conduct in relation to others and to society. Can a robot be programmed to have a moral compass? If we were only considering rules of conduct, then perhaps yes, that would be possible. We could establish a series of rules and sanctions that a computer assisted robot could rigorously apply for any violation. The state and many religions already do that, and many individuals are quite comfortable with rigorous, unbendable rules. Most rules, however, have exceptions, so perhaps the robots of the future can be designed to be flexible, that is, human.
BOUNDEDNESS OF MAXIMAL FUNCTIONS ON NONDOUBLING PARABOLIC MANIFOLDS WITH ENDS
Authors: DOAN HONG CHUONG
Published: March 2020

Let $M$ be a nondoubling parabolic manifold with ends. First, this paper investigates the boundedness of the maximal function associated with the heat semigroup ${\mathcal{M}}_{\unicode[STIX]{x1D6E5}}f(x):=\sup _{t>0}|e^{-t\unicode[STIX]{x1D6E5}}f(x)|$ where $\unicode[STIX]{x1D6E5}$ is the Laplace–Beltrami operator acting on $M$. Then, by combining the subordination formula with the previous result, we obtain the weak type $(1,1)$ and $L^{p}$ boundedness of the maximal function ${\mathcal{M}}_{\sqrt{L}}^{k}f(x):=\sup _{t>0}|(t\sqrt{L})^{k}e^{-t\sqrt{L}}f(x)|$ on $L^{p}(M)$ for $1<p\leq \infty$ where $k$ is a nonnegative integer and $L$ is a nonnegative self-adjoint operator satisfying a suitable heat kernel upper bound. An interesting thing about the results is the lack of both doubling condition of $M$ and the smoothness of the operators’ kernels.
Modeling and analysis of medium-resolution integrated-light spectra of globular clusters in dwarf galaxies
Authors: Sharina Margarita E. , Shimansky Vladislav V.
Published: March 2020

The study of ages, helium mass fraction (Y) and chemical composition of globular clusters in dwarf galaxies is important for understanding the physical conditions at the main evolutionary stages of the host galaxies and for constraining the build-up histories of large galaxies. We present the analysis of integrated-light spectra of 8 extragalactic and 20 Galactic globular clusters (GCs) using our population synthesis method. We calculate synthetic spectra of GCs according to the defined stellar mass functions using model atmospheres and stellar parameters ([Fe/H], Teff, and logg) set by theoretical isochrones. The main advantage of our method is the ability to determine not only chemical composition but also the age and mean Y in a cluster by modelling and analysis of Balmer absorption lines. The knowledge of Y and anomalies of light elements in star clusters is one of the key points for understanding the phenomenon of multiple stellar populations.
STRucture and Evolution of the GAlaxy (STREGA): The case of Pal 3
Authors: Moretti M. I. , Musella I. , Marconi M. , Ripepi V. , Molinaro R.
Published: March 2020

In the context of the STRucture and Evolution of the GAlaxy survey, we describe the preliminary results obtained for the fields around the globular cluster Pal 3 (about 2.75 square degrees), by exploiting the obtained g, r, i time series photometry. The final aim is to use variable stars as tools to verify and study the presence of streams around Pal 3. We found 20 candidate variable stars of which 7 RR Lyrae stars possibly belonging to Pal 3, also at large distance from the center. The distribution of the candidate RR Lyrae seems to confirm a preferential distribution in the north-east direction, confirming previous results in literature.
‘Status update’ for the AGB scenario for the formation of multiple populations
Authors: D’Antona Francesca
Published: March 2020

The Asymptotic Giant Branch (AGB) scenario for the formation of multiple populations has been quantitatively studied in the course of the last twenty years, examining the aspects both of nucleosynthesis and of the dynamics of formation of new stars in a cooling flow at the center of the first generation cluster, and of the following N–body evolution. The large complexity of these studies finds many validations in the properties of multiple populations. Here I shortly summarize recent accomplishments in the study of the evolution of massive AGBs and super–AGBs including the explanation of anomalous high lithium abundances in ‘extreme’ second generation stars in ω Cen and NGC 2808.
Investigation of the nearby open clusters with Gaia DR2 data
Authors: Seleznev Anton F. , Danilov Vladimir M. , Carraro Giovanni
Published: March 2020

Gaia DR2 catalog provides a unique possibility to study the three-dimensional structure and the three-dimensional velocity field of the nearby open clusters. We can either select stars with a maximum membership probability and the most accurate values for the proper motions, parallaxes, and the radial velocities, or study these clusters statistically using overwhelmingly large areas of sky of tens by tens degrees. The second approach allows us to reveal the extensive outer parts of the clusters - a corona and the tidal tails and to study the luminosity and mass functions of these clusters. We present the first results of the investigation of several nearby open clusters, including Pleiades, Alpha Persei, Ruprecht 147.
Structure of the open cluster Collinder 463 revealed by Gaia astrometry
Authors: Semionov Dmitrij
Published: March 2020

In this work we present our new estimates of the fundamental parameters of the open cluster Collinder 463, based on Gaia astrometric and PanSTARRS photometric data. In addition to updating previously available parameter values we highlight the existence of an extended stellar “halo” which is closely related to the presently known star cluster.
A new diagnostic for multiple populations: NGC 6388 as a test case
Authors: Bragaglia Angela , Carretta Eugenio
Published: March 2020

Recently, the sample size of stars with detailed, homogeneous abundances in the massive bulge Globular cluster NGC 6388 expanded to 185 giants. We use this wealth of data to present first results on its multiple stellar populations. In particular, i) we introduce a new diagnostic plot to survey the occurrence of very high temperature for H-burning in the first-generation polluters, and ii) we pinpoint a restricted temperature range reached by polluters at work in NGC 6388.
MOCCA-SURVEY Database I: Dissolution of tidally filling star clusters harboring black hole subsystem
Authors: Giersz Mirek , Askar Abbas , Wang Long , Hypki Arkadiusz , Leveque Agostino , Spurzem Rainer
Published: March 2020

We investigate the dissolution process of star clusters embedded in an external tidal field and harboring a subsystem of stellar-mass black hole. For this purpose we analyzed the MOCCA models of real star clusters contained in the Mocca Survey Database I. We showed that the presence of a stellar-mass black hole subsystem in tidally filling star cluster can lead to abrupt cluster dissolution connected with the loss of cluster dynamical equilibrium. Such cluster dissolution can be regarded as a third type of cluster dissolution mechanism. We additionally argue that such a mechanism should also work for tidally under-filling clusters with a top-heavy initial mass function.
Mass loss of different stellar populations in globular clusters
Authors: Tailo Marco
Published: March 2020

Once the age and metallicity are fixed, the colour distribution of horizontal branch stars in a globular cluster depends on few parameters: the helium abundance of the population and the mass lost during the pre-HB stages. These parameters are usually derived from the HB itself, hence they are degenerate. Breaking this degeneracy and understanding their role is a tricky and challenging problem that no study has solved yet. Combining the information obtained from the chromosome maps and the analysis of multi-band photometry with state of the art stellar evolution models, we can obtain a solid estimate of Y for the various stellar populations in a GC. We will then have, for the first time, the possibility to break the parameters’ degeneracy on the HB, understand the role of the mass loss, and lay the foundation to build another piece of the multiple populations mosaic.
N-body chaos, phase-space transport and relaxation in numerical simulations
Authors: Di Cintio Pierfrancesco , Casetti Lapo
Published: March 2020

Using direct N-body simulations of self-gravitating systems we study the dependence of dynamical chaos on the system size N. We find that the N-body chaos quantified in terms of the largest Lyapunov exponent Λmax decreases with N. The values of its inverse (the so-called Lyapunov time tλ) are found to be smaller than the two-body collisional relaxation time but larger than the typical violent relaxation time, thus suggesting the existence of another collective time scale connected to many-body chaos.
The Chandrasekhar Spitzer controversy and the (ir)relevance of distant interactions
Authors: van Albada Tjeerd S. , Szomoru Arpad
Published: March 2020

We have done N-body simulations with N up to 106, with the aim to determine whether fluctuations in the force field of a globular cluster are caused by nearby or distant encounters. We find that distant encounters are insignificant, in agreement with Chandrasekhar’s expectations, contrary to general opinion.
Modeling Pulsars in dense star clusters
Authors: Ye Claire S. , Kremer Kyle , Chatterjee Sourav , Rodriguez Carl L. , Rasio Frederic A.
Published: March 2020

Over a hundred millisecond radio pulsars (MSPs) have been observed in globular clusters (GCs), motivating theoretical studies of the formation and evolution of these sources through stellar evolution coupled to stellar dynamics. Here we study MSPs in GCs using realistic N-body simulations with our Cluster Monte Carlo code. We show that neutron stars (NSs) formed in electron-capture supernovae can be spun up through mass transfer to form MSPs. Both NS formation and spin-up through accretion are greatly enhanced through dynamical interaction processes. We find that our models for average GCs at the present day with masses ≍ 2 × 105M⊙ can produce up to 10 – 20 MSPs, while a very massive GC model with mass ≍ 106M⊙ can produce close to 100. We show that the number of MSPs is anti-correlated with the total number of stellar-mass black holes (BHs) retained in the host cluster. As a result, the number of MSPs in a GC could be used to place constraints on its BH population. Some intrinsic properties of MSP systems in our models (such as the magnetic fields and spin periods) are in good overall agreement with observations.
Chemical abundances of four red supergiants star clusters (RSGCs) in Scutum-Crux arm
Authors: Chun Sang-Hyun
Published: March 2020

We investigate the spectral properties of red supergiant stars in the four RSGCs (RSGC2, RSGC3, RSGC4, RSGC5, and Alicante 10) in the Scutum-Crux arm of the Milky Way. The high-resolution (R: 45,000) near-infrared (H and K bands) spectra for 41 red supergiants were obtained using IGRINS at Gemini South telescope. The calibration of effective temperatures and gravities are derived based on the EWTi and EWCO using supergiants in IGIRNS library. The resulted temperatures and gravities are consistent with previous results. Model spectra were synthesized using derived stellar parameters from which we estimate metallicities and chemical abundances like α-elements. In our preliminary result, we find that overall four RSGCs indeed have sub-solar metallicities as already known in previous studies. The metallicity properties of RSGCs are far off the nominal metallicity trend in this region, and this suggests recent low-metallicity gas fueling into the inner disk and bulge.
The evolution of intracluster medium in stellar clusters
Authors: Chantereau W.
Published: March 2020

Stars in globular clusters lose mass through slow stellar winds that are retained by the stellar cluster and should contribute to build up a non-negligible intracluster medium over time. However, all the observations so far found only a negligible amount of gas in GCs. We propose here to test different mechanisms such as ram-pressure stripping by the motion of the GC in the Galactic halo medium and the inclusion of ionising sources to explain the lack of gas in GCs. We use full 3D hydrodynamical simulations taking into account stellar winds, ionising radiation, radiative heating and radiative pressure. We find that the combined effect of ram-pressure and ionisation are able to explain the negligible amount of gas observed in the core of intermediate-mass and massive GCs.
Possible connection between P Cygni and neighboring open clusters
Authors: Beradze Sopia , Kochiashvili Nino
Published: March 2020

According to earlier investigations by Turner and co-authors, P Cygni could be a member of a hypothetical, sparsely populated open cluster. The star lies near the east boundary of this hypothetical cluster. There is another known open cluster, IC 4996, in the vicinity of P Cygni. The same authors believe that the above mentioned two clusters are connected to each other and they could represent a double cluster. As P Cygni is a hypergiant and consequently has very strong and variable stellar wind, so a cluster membership can enable us to determine the age, distance, and reddening of the star relatively precisely. We used new data of different catalogues, for example, PPMXL and Gaia and tried to resolve the problem.
SOWAT: High-resolution imaging with only partial AO correction
Authors: Bosco Felix , Pott Jörg-Uwe , Schödel Rainer
Published: March 2020

Observations of dense stellar systems such as globular clusters (GCs) are limited in resolution by the optical aberrations induced by atmospheric turbulence (atmospheric seeing). At the example of holographic speckle imaging, we now study, to which degree image reconstruction algorithms are able to remove residual aberrations from a partial adaptive optics (AO) correction, such as delivered from ground-layer AO (GLAO) systems. Simultaneously, we study, how such algorithms benefit from being applied to pre-corrected instead of natural point-spread functions (PSFs). We find that using partial AO corrections already lowers the demands on the holography reference star by ∼3 mag, what makes more fields accessible for this technique, and also that the discrete integration times may be chosen about 2–3× longer, since the effective wavefront evolution is slowed down by removing the perturbation power.
Merging black holes of any size and hierarchy
Authors: Fragione Giacomo
Published: March 2020

With the hundreds of merging binary black holes (BHs) expected to be detected by LIGO, LISA, and other upcoming instruments, the modelling of astrophysical channels that lead to the formation of compact BH binaries has become of crucial importance. BHs of any size can form bound systems in every astrophysical environment, from the field to galactic nuclei. If a binary is too wide, it needs a catalysis process to harden and merge, as in the case a third objects orbiting the BH binary on a distant orbit. In this case, Kozai-Lidov cycles can pump up the binary eccentricity, thus driving it to a merger thanks to efficient energy dissipation at the pericenter. Some remarkable scenarios where the Kozai-Lidov mechanism operates are in triple and quadruple systems of stellar BHs, and in intermediate-mass BH-stellar BH binaries in orbit around a central supermassive BH in galactic nuclei.
Globular cluster system of NGC 3613, a massive elliptical galaxy in a poor environment
Authors: De Bórtoli Bruno J. , Bassino Lilia P. , Caso Juan P. , Ennis Ana I.
Published: March 2020

We present an analysis of the globular cluster system (GCS) of the galaxy NGC 3613, an intrinsically bright elliptical galaxy (MV = −21.5) in a low density environment (it is the central galaxy of a group of a dozen galaxies). Based on Gemini/GMOS photometry of NGC 3613 we obtained the following properties for this GCS. A ‘blue tilt’ is detected in the colour-magnitude diagram. The colour distribution is bimodal, presenting the two classical globular cluster (GC) sub-populations. The spatial and azimuthal projected distributions show that red sub-population correlates with the stellar component of the host galaxy.
UVIT observations of UV-Bright stars in four Galactic Globular Clusters
Authors: Kumar Ranjan , Pradhan Ananta C. , Parthasarathy M. , Ojha Devendra K. , Mohapatra Abhisek , Murthy Jayant
Published: March 2020

We have performed photometric analysis of four Galactic globular clusters (GGCs): NGC 4147, NGC 4590, NGC 5053 and NGC 7492 using far-UV and near-UV filters of the Ultraviolet Imaging Telescope (UVIT) on-board AstroSat. With the help of color-magnitude diagrams (CMDs), we have identified ~150 blue horizontal branch stars (BHBs), and ~40 blue straggler stars (BSS) in the four GGCs. We study the temperature and radial distribution of BHBs and BSS for the four GGCs.
The collision between the Milky Way and Andromeda and the fate of their Supermassive Black Holes
Authors: Schiavi Riccardo , Capuzzo-Dolcetta Roberto , Arca Sedda Manuel , Spera Mario
Published: March 2020

Our Galaxy and the nearby Andromeda Galaxy (M31) form a bound system, even though the relative velocity vector of M31 is currently not well constrained. Their orbital motion is highly dependent on the initial conditions, but all the reliable scenarios imply a first close approach in the next 3–5 Gyrs. In our study, we simulate this interaction via direct N-body integration, using the HiGPUs code. Our aim is to investigate the dependence of the time of the merger on the physical and dynamical properties of the system. Finally, we study the dynamical evolution of the two Supermassive Black Holes placed in the two galactic centers, with the future aim to achieve a proper resolution to follow their motion until they form a tight binary system.
Kinematics of multiple stellar populations in Globular Clusters with Gaia
Authors: Cordoni G. , Milone A. P. , Mastrobuono-Battisti A. , Marino A. F. , Lagioia E. P. , Tailo M.
Published: March 2020

The internal dynamics of multiple stellar populations in Globular Clusters (GCs) provides unique constraints on the physical processes responsible for their formation. Specifically, the present-day kinematics of cluster stars, such as rotation and velocity dispersion, seems to be related to the initial configuration of the system. In recent work (Milone et al. 2018), we analyzed for the first time the kinematics of the different stellar populations in NGC 0104 (47 Tucanae) over a large field of view, exploiting the Gaia Data Release 2 proper motions combined with multi-band ground-based photometry. In this paper, based on the work by Cordoni et al. (2019), we extend this analysis to six GCs, namely NGC 0288, NGC 5904 (M 5), NGC 6121 (M 4), NGC 6752, NGC 6838 (M 71) and further explore NGC 0104. Among the analyzed clusters only NGC 0104 and NGC 5904 show significant rotation on the plane of the sky. Interestingly, multiple stellar populations in NGC 5904 exhibit different rotation curves.
Helium variations in Galactic and extragalactic Globular Clusters
Authors: Lagioia Edoardo P. , Milone Antonino P. , Marino Anna F. , Dotter Aaron , Cordoni Giacomo , Tailo Marco
Published: March 2020

The recent measurements of internal variations of helium in Galactic and extragalactic Globular Clusters (GCs) set binding constraints to the models of formation of Multiple Populations (MPs) in GCs, and gave rise, at the same time, to crucial questions related with the influence of the environment on MP formation as well as with the role played by GCs in the early galactic formation. We present the most recent estimates of helium enrichment in the main populations of a large sample of Galactic and extragalactic GCs.
The Coupled Brains of Captivated Audiences
Authors: Schmälzle Ralf , Grall Clare
Published: March 2020

Abstract. Suspense not only creates a strong psychological tension within individuals, but it does so reliably across viewers who become collectively engaged with the story. Despite its prevalence in media psychology, limited work has examined suspense from a media neuroscience perspective, and thus the biological underpinnings of suspense remain unknown. Here we examine continuous brain responses of 494 viewers watching a suspenseful movie. To create a time-resolved measure of the degree to which a movie aligns audience-wide brain responses, we computed dynamic inter-subject correlations of functional magnetic resonance imaging (fMRI) time series among all viewers using sliding-window analysis. In parallel, we captured in-the-moment reports of suspense in an independent sample via continuous response measurement (CRM). We found that dynamic inter-subject correlations over the course of the movie tracked well with the reported suspense in the CRM sample, particularly in regions associated with emotional salience and higher cognitive processes. These results are compatible with theoretical views on motivated attention and psychological tension. The finding that fMRI-based audience response measurement relates to audience reports of suspense creates new opportunities for research on the mechanisms of suspense and other entertainment phenomena and has applied potential for measuring audience responses in a nonreactive and objective fashion.