Triggered fragmentation in gravitationally unstable discs: forming fragments at small radii

We carry out three dimensional radiation hydrodynamical simulations of gravitationally unstable discs using to explore the movement of mass in a disc following its fragmentation. Compared to a more quiescent state before it fragments, the radial velocity of the gas increases by up to a factor of ~2-3 after fragmentation. While the mass movement occurs both inwards and outwards, the inwards motion can cause the inner spirals to be sufficiently dense that they may become unstable and potentially fragment. Consequently, the dynamical behaviour of fragmented discs may cause subsequent fragmentation at smaller radii after an initial fragment has formed in the outer disc.Comment: Submitted to the conference proceedings of: Instabilities and Structures in Proto-Planetary Disks. 5 pages; 4 figure

Exploring the Complexities of Suicide Bereavement Research

Statistics indicate a projected increase in the number of suicides by those in receipt of mental health services in England. Research has also shown that the impact of suicide on individuals who have lost someone to suicide have an increased risk of poor physical and mental health, including a higher risk of suicidality. However, research within suicide bereavement is limited due to the lack of methodologically robust studies involving those bereaved through suicide. This paper will offer an overview of current debates in the suicide bereavement literature and discuss a forthcoming qualitative study that will examine the impact of suicide by those in receipt of mental health services on their families. The current research will utilise a constructivist grounded theory approach. Analysis of the data will include a process of coding and comparison, leading to theory generation. This study aims to contribute to knowledge of the impact of suicide on family members (where the deceased was in receipt of mental health services) and how to provide effective post-intervention support for these particular families

The Impact of school meals on school participation: Evidence from rural India

This paper assesses the effect of transition from monthly distribution of free food grains to the daily provision of free cooked meals to school children on enrollments and attendance in a rural area of India. School panel data allow a difference-in-differences estimation strategy to address possible endogeneity of program placement. The results suggest that program transition had a significant impact on improving the daily participation rates of children in lower grades. The average monthly attendance rate of girls in grade 1 was more than 12 percentage points higher while there was a positive but insignificant effect on grade 1 boys' attendance rate. The impact on enrollment levels was insignificant.school meals, attendance, enrollment

Cosmological reconstruction and energy bounds in f(R,RαβRαβ,ϕ)f(R,R_{\alpha \beta}R^{\alpha\beta},\phi) gravity

We discuss the cosmological reconstruction of $f(R,R_{\alpha\beta}R^{\alpha\beta},\phi)$ (where $R$, $R_{\alpha\beta}R^{\alpha\beta}$ and $\phi$ represents the Ricci scalar, Ricci invariant and scalar field) corresponding to power law and de Sitter evolution in the framework of FRW universe model. We derive the energy conditions for this modified theory which seem to be more general and can be reduced to some known forms of these conditions in general relativity, $f(R)$ and $f(R,\phi)$ theories. We have presented the general constraints in terms of recent values of snap, jerk, deceleration and Hubble parameters. The energy bounds are analyzed for reconstructed as well as known models in this theory. Finally, the free parameters are analyzed comprehensively.Comment: 27 pages, 3 figure

Impact of Prenatal Checkups of Mothers and Immunization of Children on the Health Status of Children (0-3 years) - A Study in Rural areas of Aligarh District, Uttar Pradesh.

Background and objectives: A survey based study on rural areas of Aligarh District was conducted to assess the prenatal checkups pregnant women and its effects on health status of children between the age of (0-3 years), and immunization received by children and its effects on their health status. Methods: Five hundred children from five villages of rural areas of Aligarh District were randomly selected. For the purpose of the study, a self prepared structured interview schedule was used. To get the qualitative information of the study anthropometric measures include height weight were used for assessing growth pattern of the child. The stepwise analysis of two variables height for age and weight for age was done on the basis of Water low’s and Gomez’ classification. To examine the relationship between Health Status of the child and selected variable that affects Health Status of children, Chi-square test was employed. Results: Based on Gomez’ classification out of 88% mothers who did not go for prenatal ups majority 80% of children were underweight, and 80% of children who did not receive immunization majority 60% were underweight. Based on Waterlow’s classification majority 68% of children were stunted whose mother did not go for prenatal checkups and 50% of their children were stunted who did not receive immunization. Conclusion: Majority of children were stunted whose mother did not go for prenatal checkup and the children who did not receive immunization

Optimal Weighting for Exam Composition

A problem faced by many instructors is that of designing exams that accurately assess the abilities of the students. Typically these exams are prepared several days in advance, and generic question scores are used based on rough approximation of the question difficulty and length. For example, for a recent class taught by the author, there were 30 multiple choice questions worth 3 points, 15 true/false with explanation questions worth 4 points, and 5 analytical exercises worth 10 points. We describe a novel framework where algorithms from machine learning are used to modify the exam question weights in order to optimize the exam scores, using the overall class grade as a proxy for a student's true ability. We show that significant error reduction can be obtained by our approach over standard weighting schemes, and we make several new observations regarding the properties of the "good" and "bad" exam questions that can have impact on the design of improved future evaluation methods

Non-convergence of the critical cooling timescale for fragmentation of self-gravitating discs

We carry out a resolution study on the fragmentation boundary of self-gravitating discs. We perform three-dimensional Smoothed Particle Hydrodynamics simulations of discs to determine whether the critical value of the cooling timescale in units of the orbital timescale, beta_{crit}, converges with increasing resolution. Using particle numbers ranging from 31,250 to 16 million (the highest resolution simulations to date) we do not find convergence. Instead, fragmentation occurs for longer cooling timescales as the resolution is increased. These results suggest that at the very least, the critical value of the cooling timescale is longer than previously thought. However, the absence of convergence also raises the question of whether or not a critical value exists. In light of these results, we caution against using cooling timescale or gravitational stress arguments to deduce whether gravitational instability may or may not have been the formation mechanism for observed planetary systems.Comment: Accepted for publication by MNRAS Letters. 6 pages, 3 figure

An adaptive quasi harmonic broadcasting scheme with optimal bandwidth requirement

The aim of Harmonic Broadcasting protocol is to reduce the bandwidth usage in video-on-demand service where a video is divided into some equal sized segments and every segment is repeatedly transmitted over a number of channels that follows harmonic series for channel bandwidth assignment. As the bandwidth of channels differs from each other and users can join at any time to these multicast channels, they may experience a synchronization problem between download and playback. To deal with this issue, some schemes have been proposed, however, at the cost of additional or wastage of bandwidth or sudden extreme bandwidth requirement. In this paper we present an adaptive quasi harmonic broadcasting scheme (AQHB) which delivers all data segment on time that is the download and playback synchronization problem is eliminated while keeping the bandwidth consumption as same as traditional harmonic broadcasting scheme without cost of any additional or wastage of bandwidth. It also ensures the video server not to increase the channel bandwidth suddenly that is, also eliminates the sudden buffer requirement at the client side. We present several analytical results to exhibit the efficiency of our proposed broadcasting scheme over the existing ones.Comment: IEEE International Conference on Informatics, Electronics & Vision (ICIEV), 2013, 6pages, 8 figure