Current perspectives on the role of TRAMP in nuclear RNA surveillance and quality control

The TRAMP complex assists the nuclear exosome to degrade a broad range of ribonucleic acid (RNA) substrates by increasing both exoribonucleolytic activity and substrate specificity. However, how the interactions between the TRAMP subunits and the components of the nuclear exosome regulate their functions in RNA degradation and substrate specificity remain unclear. This review aims to provide a summary of the recent findings on the role of the TRAMP complex in nuclear RNA degradation. The new insights from recent structural biological studies are discussed.published_or_final_versio

Coupling and Coordination in Gene Expression Processes with Pre-mRNA Splicing

A processing is a tightly regulated and highly complex pathway which includes transcription, splicing, editing, transportation, translation and degradation. It has been well-documented that splicing of RNA polymerase II medicated nascent transcripts occurs co-transcriptionally and is functionally coupled to other RNA processing. Recently, increasing experimental evidence indicated that pre-mRNA splicing influences RNA degradation and vice versa. In this review, we summarized the recent findings demonstrating the coupling of these two processes. In addition, we highlighted the importance of splicing in the production of intronic miRNA and circular RNAs, and hence the discovery of the novel mechanisms in the regulation of gene expression.published_or_final_versio

Information sharing promotes prosocial behaviour

More often than not, bad decisions are bad regardless of where and when they are made. Information sharing might thus be utilized to mitigate them. Here we show that sharing information about strategy choice between players residing on two different networks reinforces the evolution of cooperation. In evolutionary games, the strategy reflects the action of each individual that warrants the highest utility in a competitive setting. We therefore assume that identical strategies on the two networks reinforce themselves by lessening their propensity to change. Besides network reciprocity working in favour of cooperation on each individual network, we observe the spontaneous emergence of correlated behaviour between the two networks, which further deters defection. If information is shared not just between individuals but also between groups, the positive effect is even stronger, and this despite the fact that information sharing is implemented without any assumptions with regard to content

Stress and its associated factors among medical students in a public medical faculty, Malaysia

Background: Stress is common among university students. Levels of stress vary between the students of different courses in the university and many factors are associated with it. As compared to other professional courses, medical students are more prone to get depressed because medical education is known to be stressful and very demanding. Materials and Methods: This is a cross-sectional study using a pretested, self-administered questionnaire involving all medical students in academic session 2013/2014. The questionnaire consists of 3 parts; socio-demographic information, family factors and personal factors; Depression, Anxiety and Stress Score 21 questionnaire (DASS 21) and Duke University Religion Index (DUREL). DUREL measures religiosity in 3 scales namely; organized religious activity (ORA), non-organized religious activity (NORA) and intrinsic religiosity (IR). The questionnaire was distributed to all medical students available in FMHS during the data collection period. Data collected were analyzed using IBM SPSS version 21. Result: Of 409 medical students, 329 (80.4%) responded. Most (50.5%) were aged 22 years and above, majority (62.3%) were female students. Respondents were mainly Malay (54.4%) and Muslims (56.8%). Stress prevalence in medical students were 19.8%. Stress prevalence was higher among students aged ≤ 21 years (22.1%), male (20.2%), Indian (24.0%) and Hindus (31.6%),among students with father of primary education level (21.4%), mother of tertiary education level (25%) and low income family (21.4%). Prevalence of stress among students in pre-clinical year (21.4%) and clinical year students (17.9%), p>0.05. Stress among students who did not undergo matriculation course and those who attended were 21.7% and 18.8%, respectively. Proportion of stress students who entered medical school not on their own choice and on their own choice were 24.3% and 18.5%, respectively, p>0.05. Medical students with poor ORA and NORA showed higher proportion of stress (20.2%, 20.6% respectively) however, students with good IR had higher proportion of stress compared to those with poor IR (20.0%, 19.5%, p>0.05). Conclusion: Stress is prevalent among almost one-fifth of medical students, especially those in their pre-clinical years of studies. Students’ involvement in religious activities could be beneficial to prevent stress. Further research is needed to assess the effect of medical training on stress and the effect of religiosity on stress coping

Quasispecies distribution of Eigen model

We study sharp peak landscapes (SPL) of Eigen model from a new perspective about how the quasispecies distribute in the sequence space. To analyze the distribution more carefully, we bring forth two tools. One tool is the variance of Hamming distance of the sequences at a given generation. It not only offers us a different avenue for accurately locating the error threshold and illustrates how the configuration of the distribution varies with copying fidelity $q$ in the sequence space, but also divides the copying fidelity into three distinct regimes. The other tool is the similarity network of a certain Hamming distance $d_{0}$, by which we can get a visual and in-depth result about how the sequences distribute. We find that there are several local optima around the center (global optimum) in the distribution of the sequences reproduced near the threshold. Furthermore, it is interesting that the distribution of clustering coefficient $C(k)$ follows lognormal distribution and the curve of clustering coefficient $C$ of the network versus $d_{0}$ appears as linear behavior near the threshold.Comment: 13 pages, 6 figure

Multiphase flow numerical simulation of ladle bottom powder injection

Numerical simulations were performed on bottom injection of calcium oxide particles through double nozzle porous bricks into a 300 t hot metal ladle. The distribution characteristics of the calcium oxide particles in the ladle were predicted and analyzed. The modeling results show that, when the bottom blown porous bricks are located symmetrically off-centre by 1 / 2 ladle bottom radius and the injection speed of the calcium oxide particles is 7 m / s, an optimum distribution of the calcium oxide particles in the hot metal bath in the ladle can be achieved. This will provide a reference for evaluating the feasibility of applying bottom injection of the calcium oxide powder into hot metal ladles for desulfurization in the actual production process