scholarly journals Impact of tides on the transit-timing fits to the TRAPPIST-1 system

2020 ◽  
Vol 635 ◽  
pp. A117 ◽  
Author(s):  
E. Bolmont ◽  
B.-O. Demory ◽  
S. Blanco-Cuaresma ◽  
E. Agol ◽  
S. L. Grimm ◽  
...  

Transit timing variations (TTVs) can be a very efficient way of constraining masses and eccentricities of multi-planet systems. Recent measurements of the TTVs of TRAPPIST-1 have led to an estimate of the masses of the planets, enabling an estimate of their densities and their water content. A recent TTV analysis using data obtained in the past two years yields a 34 and 13% increase in mass for TRAPPIST-1b and c, respectively. In most studies to date, a Newtonian N-body model is used to fit the masses of the planets, while sometimes general relativity is accounted for. Using the Posidonius N-body code, in this paper we show that in the case of the TRAPPIST-1 system, non-Newtonian effects might also be relevant to correctly model the dynamics of the system and the resulting TTVs. In particular, using standard values of the tidal Love number k2 (accounting for the tidal deformation) and the fluid Love number k2f (accounting for the rotational flattening) leads to differences in the TTVs of TRAPPIST-1b and c that are similar to the differences caused by general relativity. We also show that relaxing the values of tidal Love number k2 and the fluid Love number k2f can lead to TTVs which differ by as much as a few 10 s on a 3−4-yr timescale, which is a potentially observable level. The high values of the Love numbers needed to reach observable levels for the TTVs could be achieved for planets with a liquid ocean, which if detected might then be interpreted as a sign that TRAPPIST-1b and TRAPPIST-1c could have a liquid magma ocean. For TRAPPIST-1 and similar systems the models to fit the TTVs should potentially account for general relativity, for the tidal deformation of the planets, for the rotational deformation of the planets, and to a lesser extent for the rotational deformation of the star, which would add up to 7 × 2 + 1 = 15 additional free parameters in the case of TRAPPIST-1.

2021 ◽  
pp. 1420326X2110036
Author(s):  
Qian Xu ◽  
Chan Lu ◽  
Rachael Gakii Murithi ◽  
Lanqin Cao

A cohort case–control study was conducted in XiangYa Hospital, Changsha, China, which involved 305 patients and 399 healthy women, from June 2010 to December 2018, to evaluate the association between Chinese women’s short- and long-term exposure to industrial air pollutant, SO2 and gynaecological cancer (GC). We obtained personal and family information from the XiangYa Hospital electronic computer medical records. Using data obtained from the air quality monitoring stations in Changsha, we estimated each woman’s exposure to the industrial air pollutant, sulphur dioxide (SO2), for different time windows, including the past 1, 5, 10 and 15 years before diagnosis of the disease. A multiple logistic regression model was used to assess the association between GC and SO2 exposure. GC was significantly associated with long-term SO2 exposure, with adjusted odds ratio (95% confidence interval) = 1.56 (1.10–2.21) and 1.81 (1.07–3.06) for a per interquartile range increase in the past 10 and 15 years, respectively. Sensitivity analysis showed that different groups reacted in different ways to long-term SO2 exposure. We concluded that long-term exposure to high concentration of industrial pollutant, SO2 is associated with the development of GC. This finding has implications for the prevention and reduction of GC.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
S Brolin Låftman ◽  
Y Bjereld ◽  
B Modin ◽  
P Löfstedt

Abstract Background Students who are subjected to sexual harassment at school report lower psychological well-being than those who are not exposed. Yet, it is possible that the occurrence of sexual harassment in the school class is stressful also for those who are not directly targeted, with potential negative effects on well-being for all students. The aim was to examine whether sexual harassment at the student- and at the class-level was associated with students' psychological complaints. Methods Data from the Swedish Health Behaviour in School-aged Children (HBSC) of 2017/18 was used, with information from students aged 11, 13 and 15 years (n = 3,720 distributed across 209 classes). Psychological complaints were constructed as a summative index of four items capturing how often the student had felt low, felt irritable or bad tempered, felt nervous, or had difficulties to fall asleep, during the past six months (Cronbach's alpha=0.78). Sexual harassment at the student-level was measured by one item concerning bullying at school: “Other students have exposed me to sexual jokes”. Students who reported that this had happened at least “2 or 3 times a month” were classified as exposed to sexual harassment at school. Sexual harassment at the class-level was defined as the school class proportion of students exposed to sexual harassment, reported in per cent. Two-level linear regression analysis was applied. Results Students who had been exposed to sexual harassment had higher levels of psychological complaints (b = 2.74, p < 0.001). The proportion of students in the school class who had been exposed to sexual harassment was also associated with higher levels of psychological complaints, even when adjusting for sexual harassment at the student-level, gender and grade (b = 0.03, p = 0.015). Conclusions Sexual harassment is harmful for those who are exposed, but may also affect other students negatively. Thus, a school climate free from sexual harassment will profit all students. Key messages Using data collected among students aged 11, 13 and 15 years, this study showed that sexual harassment at the student- and class-level was associated with higher levels of psychological complaints. Sexual harassment is harmful for those who are exposed, but may also affect other students negatively. Thus, a school climate free from sexual harassment will profit all students.


2011 ◽  
Vol 243-249 ◽  
pp. 6292-6295 ◽  
Author(s):  
Rong Yau Huang ◽  
Li Hsu Yeh ◽  
Hao Hsien Chen ◽  
Jyh Dong Lin ◽  
Ping Fu Chen ◽  
...  

This study examines construction waste generation and management in Taiwan. We verify the factors probable affecting the output of construction wastes by using data for the output of declared construction wastes produced from demolition projects in Taiwan in the last year, expert interviews, and research achievements in the past, and find “ on-site separation” is the factor with effects on the output of construction wastes via cross-correlation by algorithms such as K-Means and Decision Tree C5.0. It can be seen that the output (0.092(t/M3) with on-site separation or 0.329(t/M3) without on-site separation is highly correlated with the composition ratio of construction wastes and referred to as a valid conclusion.


2021 ◽  
pp. 002204262110004
Author(s):  
Alejandro Azofeifa ◽  
Rosalie L. Pacula ◽  
Margaret E. Mattson

Given the rapidly changing U.S. cannabis legislation landscape, the aim of this article is to describe individuals who self-reported growing cannabis in the past year by selected characteristics and geographical location. Using data from 2010 to 2014 National Survey on Drug Use and Health, we conducted bivariate chi-square tests and ran a multivariable logistic regression model to examine the indicators associated with growing cannabis. Approximately, 484,000 individuals aged 12+ self-reported growing cannabis in the past year (1.6% of marijuana users). Predictors of growing cannabis included being male and self-reported reporting using cannabis for a greater number of days. Data showed differences in the proportion of cannabis growers by the state of residence. Obtaining a baseline estimate of cannabis growing practices prior to recreational cannabis markets emerging (2014) is important because such practices may undermine efforts to discourage diversion to youth. Tracking these acquisition patterns will better inform content for public health messaging and prevention education, particularly those targeting youth.


2004 ◽  
Vol 18 (4) ◽  
pp. 255-257
Author(s):  
Robert Hilsden

Longobardi and colleagues examined the effect of inflammatory bowel disease (IBD) on employment, using data from 10,891 respondents aged 20 to 64 years from the 1998 cycle of the Canadian National Population Health Survey (NPHS) (1). This sample included 187 (1.7%) subjects who self-reported IBD or a similar bowel disorder. A significantly greater proportion of IBD than non-IBD respondents reported that they were not in the labour force (28.9% versus 18.5%). Even after adjusting for other factors (age group, level of pain, etc), subjects with IBD had a 2.9% higher nonparticipation rate (21.4%). For example, among people not hospitalized within the past year and with no limitation of activities due to pain, IBD subjects were 1.2 times more likely to be unemployed than those without IBD. Subjects who reported high levels of pain had a very high probability of being out of the labour force. Based on Canadian annual compensation data for all employed persons in Canada, and age- and sex-specific prevalence, and incidence rates for IBD, the authors estimated that there are 119,980 IBD patients between the ages of 20 and 64 years in Canada and that this group includes 3479 people who are not in the labour force. This translates into lost wages of $104.2 million, or $868 per IBD patient


Author(s):  
Ram Brustein ◽  
Yotam Sherf

The response of a gravitating object to an external tidal field is encoded in its Love numbers, which identically vanish for classical black holes (BHs). Here we show, using standard time-independent quantum perturbation theory, that for a quantum BH, generically, the Love numbers are nonvanishing and negative. We calculate the quadrupolar electric quantum Love number of slowly rotating BHs and show that it depends most strongly on the first excited level of the quantum BH. Finally, we discuss the detectability of the quadrupolar quantum Love number in future precision gravitational-wave observations and show that, under favourable circumstances, its magnitude is large enough to imprint an observable signature on the gravitational waves emitted during the inspiral. Phase of two moderately spinning BHs.


2018 ◽  
Vol 45 (8) ◽  
pp. 1174-1191 ◽  
Author(s):  
H. Daniel Butler ◽  
Starr Solomon ◽  
Ryan Spohn

A number of studies have identified “what works” in regard to the successful implementation of correctional programming over the past several decades. Few studies, however, have examined the complexities associated with programming in restrictive housing. Using data from a Midwestern department of corrections, we examined whether the provision of programming in restrictive housing achieved desired outcomes (e.g., reductions in inmate misconduct). The findings revealed the amount of time served in restrictive housing and confinement in different types of restrictive housing may influence estimations of a treatment effect. As a growing number of states seek to reform the use of restrictive housing, the proper implementation of cognitive-behavioral programming may increase institutional security and safety.


2002 ◽  
Vol 11 (2) ◽  
pp. 27-53 ◽  
Author(s):  
Henrietta O'Connor ◽  
John Goodwin

Irish migrant workers still make a significant contribution to the UK labour force, but this contribution is confined to particular occupation and industry groups. This paper begins with a brief review of the literature on Irish workers employment and an argument is developed that the work of Irish-born people in Britain is still both racialised and gendered. Then, using data from the UK Quarterly Labour Force Survey (QLFS), the work experiences of over one thousand Irish-born people in the UK are explored. The findings suggest that Irish-born men and women still work in the stereotyped occupations of the past. For example, most women work in public administration and health while twenty six per cent of men work in construction. The majority of Irish-born men work in manual skilled or unskilled jobs. The paper concludes that there has been no real qualitative change in the way that Irish-born workers experience employment in the UK.


2018 ◽  
Vol 7 (2.6) ◽  
pp. 50 ◽  
Author(s):  
Pamela Chaudhury ◽  
Hrudaya Kumar Tripathy

Smartphone addiction is increasingly affecting the masses and is negatively impacting the younger generation. Several researches have been done to study the impact of internet and smartphone addiction. However no work has been done to predetermine academic performance from smartphone addiction using data mining techniques. A total of 222 University students participated in the questionnaire. The survey questionnaire consisted of demographic information, internet access pattern and smartphone addiction pattern. Data was analysed using machine learning techniques using classification models. The results further encouraged us to find the correlation between smartphone addiction and academic performance. Pearson’ correlation was used to establish that smartphone usage had a negative impact on academic performance. Additionally other attributes like internet connectivity and active involvement in outdoor sports activities were investigated. Experimental results confirmed a negative correlation of these attributes with academic performance. The findings were of immense use and could be used to reduce the internet addiction amongst the student community and also enhance their academic performance


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