Stationary and regenerative multivariate point processes

Imperial Users onl

Photolytic Hazes in the Atmosphere of 51 Eri b

We use a 1D model to address photochemistry and possible haze formation in the irradiated warm Jupiter, 51 Eridani b. The intended focus was to be carbon, but sulfur photochemistry turns out to be important. The case for organic photochemical hazes is intriguing but falls short of being compelling. If organic hazes form, they are likeliest to do so if vertical mixing in 51 Eri b is weaker than in Jupiter, and they would be found below the altitudes where methane and water are photolyzed. The more novel result is that photochemistry turns H$_2$S into elemental sulfur, here treated as S$_8$. In the cooler models, S$_8$ is predicted to condense in optically thick clouds of solid sulfur particles, whilst in the warmer models S$_8$ remains a vapor along with several other sulfur allotropes that are both visually striking and potentially observable. For 51 Eri b, the division between models with and without condensed sulfur is at an effective temperature of 700 K, which is within error its actual effective temperature; the local temperature where sulfur condenses is between 280 and 320 K. The sulfur photochemistry we have discussed is quite general and ought to be found in a wide variety of worlds over a broad temperature range, both colder and hotter than the 650-750 K range studied here, and we show that products of sulfur photochemistry will be nearly as abundant on planets where the UV irradiation is orders of magnitude weaker than it is on 51 Eri b.Comment: 24 pages including 11 figures and a tabl

A bibliometric analysis of Chinese literature on competency skills of Library Professionals in Mainland China

Taking China National Knowledge Infrastructure (CNKI) as the source of literature, this study made a bibliometric analysis on the trend of quantity of published literature, keywords of published literature, authors of published literature, institutions of published literature and publications of published literature above five aspects on the professional competency skills of library professionals in Mainland China from 2009 to 2019, and explained the development trend of the relevant research from a scientific point of view to provide a reference for the future construction of professional competency skills required for library professionals in Mainland China

Aboriginal Parental Involvement/Engagement for Student Success

An increasing body of knowledge links parental involvement with student success but few studies address Aboriginal parental involvement in urban settings. While some critics argue traditional Aboriginal knowledge is best delivered at home, Aboriginal children who share parents’ stories in the classroom benefit other children who draw connections to these stories. Moreover, Aboriginal learners need to function in mainstream Western society and in public school settings in which educators often have a difficult time engaging Aboriginal parents. Consequently, this research sought to explore the perceptions and sense of engagement of parents/caregivers in the Aboriginal Student Program (ASP) in a publicly funded secondary school in Ontario. The study was an extension of the researcher’s existing work and focused specifically on a sample of parents/caregivers taking part in an Aboriginal feast at an Ontario secondary school. Nine individuals accepted an invitation to participate in a Talking Circle and shared perceptions of their children’s educational experiences. Data were collected and coded, and findings indicated that parental involvement in children’s educational journeys contributed significantly to a sense of parental engagement in the school and in Aboriginal programs. Results also suggest that Eurocentric pedagogy can be modified in mainstream secondary schools to directly involve Aboriginal parents/caregivers. Although many participants’ stories revealed they experienced racism during their own schooling, study findings demonstrate that the parents/caregivers want to be involved in their children’s education nonetheless. This thesis discusses the data that were grounded in the participants’ voices that in turn led to several key recommendations

Nitrogen and Oxygen Photochemistry following SL9

The collision of Shoemaker Levy 9 (SL9) with Jupiter caused many new molecular species to be deposited in the Jovian stratosphere. We use a photochemical model to follow the evolution of the impact derived species. Our results regarding the nitrogen and oxygen compounds are presented here. NH3 photolysis initiates the nitrogen photochemistry. Much of the nitrogen ends up in N2, nitrogen-sulfur compounds, and HCN, but NH3 and nitriles such as C2H3CN may also exist in observable quantities for a year or so after the impacts. Oxygen species survive for a long time in the Jovian stratosphere. The only major oxygen containing compounds that exhibit dramatic changes in the lower stratosphere in the first year following the impacts are SO, SO2, and OCS - H2O, CO2, and CO are comparatively stable. We discuss the important photochemical processes operating on the nitrogen and oxygen species in the Jovian stratosphere, make prediction concerning the temporal variation of the major species, and identify molecules that might act as good tracers for atmospheric dynamics

At the intersection of sleep deficiency and opioid use: mechanisms and therapeutic opportunities

Due to the ongoing opioid epidemic, innovative scientific perspectives and approaches are urgently needed to reduce the unprecedented personal and societal burdens of nonmedical and recreational opioid use. One promising opportunity is to focus on the relationship between sleep deficiency and opioid use. In this review, we examine empirical evidence: (1) at the interface of sleep deficiency and opioid use, including hypothesized bidirectional associations between sleep efficiency and opioid abstinence; (2) as to whether normalization of sleep deficiency might directly or indirectly improve opioid abstinence (and vice versa); and (3) regarding mechanisms that could link improvements in sleep to opioid abstinence. Based on available data, we identify candidate sleep-restorative therapeutic approaches that should be examined in rigorous clinical trials

Mathematical Modeling of Host - Pest Interactions in Stage-Structured Populations: A Case of False Codling Moth [Thaumatotibia leucotreta]

False codling moth (FCM) (Thaumatotibia lucotreta) is a significant pest due to its potential economic impact on many susceptible fruits in most temperate regions of the world. Efforts to control the codling moth in the past mostly relied on the use of broad spectrum insecticide sprays, which has resulted in the development of insecticide resistance, and the disruption of the control of secondary pests. Understanding the dynamic of this pest is of great in importance in order to effectively employ the most effective control strategies. In this study, a mathematical model of host-false codling moth interactions is developed and qualitatively analysed using stability theory of system of differential equations. The basic offspring number with respect to FCM free equilibrium is obtain using next generation matrix. The condition for local and global asymptotic stability of FCM free and coexistence equilibria are established. The model is analysed numerically and graphically represented to justify the analytical results