Decays of Z Boson into Pseudoscalar Meson Pair of Different Flavours

We analyse the process Z-zero to M1 M2, where M1 and M2 are pseudoscalar mesons with quark contents of q1 q-bar and q-bar q2 respectively. At the quark level, the process-zero to q1 q2-bar, where q1 and q2 are quarks of different flavours, receives contribution only from the Z-penguin. In order to fold the quark-level process to the hadronic process, we make the fundamental assumption that the vertex of type M q q-bar can be approximated by an effective constant gamma 5 coupling. With this assumption, estimates are obtained for the cross-sections for the following processes: Z-zero to K-minus pi-plus, Z-zero to B-minus K-plus.Comment: Presented at 4th International Meeting on Frontiers of Physics (IMFP2013), Awana Resort, Malaysia, 27-30 August 201

A comparative study on the jet loop reactor and continuos stirred tank reactor in the selective hydrogenation of palm olein (I.V.64)

Jet Loop Reactor (JLR) was developed to improve the overall performance of hydrogenation processes. Nevertheless, the application of JLR in the palm oil and oleochemical industries in Malaysia is still very much sparse. A substantial amount of investment and the lack of study conducted in Malaysia on the application of JLR have retarded the retrofitment and/or replacement of the conventional CSTR with this technology. In the wake of this, a comparative study was conducted to investigate the performance of JLR in the selective hydrogenation of palm olein with an IV of 64 in comparison to the hydrogenation in the conventional CSTR system. A pilot scale JLR with a capacity of 250 liter was used in the study. The circulation of the sample in the loop was achieved via a single speed pump. The experimental result was compared with result from the CSTR experiment. A down-scaled laboratory CSTR apparatus was used in the study for this purpose. A software package, developed via Microsoft Excel 2000 and Visual Basic Application (VBA) softwares, was used to simulate the behavior of the hydrogenation process in both, JLR and CSTR, under similar capacity. The outcome of the study showed that with the limitation of single speed pump, the JLR could not matched the superiority of CSTR in the selective hydrogenation process for it required slow reaction to produce high trans fatty acids hydrogenated product. On the positive note, the developed software package is a useful tool which allows an easy method to study the behavior of the hydrogenation process of JLR and CSTR. The prediction of the CSTR process was acceptable, but the prediction of JLR process was less accurate, revealing a maximum of 30% error. It can be concluded that the present analytical method used in the simulation of JLR required improvement on the modeling of the process, or to opt for the numerical solution, to produce a much better prediction. A retrofit method was also suggested in the study, for the possibility of fitting in the JLR facility in the existing CSTR system with minimal modification, for the system to have dual function of slow and fast reactions

The Drawn-Out Battle Against Stigma: Mental Health in Modern American Comics and Graphic Novels

The discussion of mental health issues in the media significantly shapes public perceptions, most notably in negative portrayals that contribute to the stereotyping of mental health patients. Perhaps surprisingly, comics and graphic novels are forms of media that have potential to mitigate such stigma, despite earlier criticism of mental health stereotypes propagated in some comics. This is reflected in a recent trend of comics treating mental health issues in more sympathetic ways. This paper discusses three American comics from the last decade, examining depictions of post-traumatic stress disorder in Garry Trudeau\u27s comic strip, Doonesbury, around 2005-2006, schizophrenia in Nate Powell\u27s graphic novel, Swallow Me Whole (2008), and depression in a short Captain America comic (2011). An analysis of these examples reveals that comics in the United States have a unique and promising place in mental health education. Comics can reach an at-risk target audience, convey their messages in a visual and non-textual way, use narrative to present important issues in an accessible manner, use humor to enable the discussion of taboo topics, and, in some cases, use popular characters to raise the profile of a certain issue. They also have the potential to serve directly as therapy for mental health patients, a trend currently more visible in the United Kingdom and Canada. The comics and graphic novels discussed show, perhaps a larger trend of the media moving away from stereotyping and towards a greater visibility and understanding of mental health issues

Exact calculations of vertex sˉγb\bar{s}\gamma b and sˉZb\bar{s} Z b in the unitary gauge

In this paper, we present the exact calculations for the vertex $\bar{s}\gamma b$ and $\bar{s} Z b$ in the unitary gauge. We found that (a) the divergent- and $\mu$-dependent terms are left in the effective vertex function $\Gamma^\gamma_\mu(p,k)$ for $b \to s \gamma$ transition even after we sum up the contributions from four related Feynman diagrams; (b) for an on-shell photon, such terms do not contribute et al; (c) for off-shell photon, these terms will be canceled when the contributions from both vertex $\bar{s}\gamma b$ and $\bar{s} Z b$ are taken into account simultaneously, and therefore the finite and gauge independent function $Z_0(x_t)=C_0(x_t)+ D_0(x_t)/4$, which governs the semi-leptonic decay $b \to s l^- l^+$, is derived in the unitary gauge.Comment: 13 pages, 2 figures, Revte

Abelian networks IV. Dynamics of nonhalting networks

An abelian network is a collection of communicating automata whose state transitions and message passing each satisfy a local commutativity condition. This paper is a continuation of the abelian networks series of Bond and Levine (2016), for which we extend the theory of abelian networks that halt on all inputs to networks that can run forever. A nonhalting abelian network can be realized as a discrete dynamical system in many different ways, depending on the update order. We show that certain features of the dynamics, such as minimal period length, have intrinsic definitions that do not require specifying an update order. We give an intrinsic definition of the \emph{torsion group} of a finite irreducible (halting or nonhalting) abelian network, and show that it coincides with the critical group of Bond and Levine (2016) if the network is halting. We show that the torsion group acts freely on the set of invertible recurrent components of the trajectory digraph, and identify when this action is transitive. This perspective leads to new results even in the classical case of sinkless rotor networks (deterministic analogues of random walks). In Holroyd et. al (2008) it was shown that the recurrent configurations of a sinkless rotor network with just one chip are precisely the unicycles (spanning subgraphs with a unique oriented cycle, with the chip on the cycle). We generalize this result to abelian mobile agent networks with any number of chips. We give formulas for generating series such as $$\sum_{n \geq 1} r_n z^n = \det (\frac{1}{1-z}D - A )$$ where $r_n$ is the number of recurrent chip-and-rotor configurations with $n$ chips; $D$ is the diagonal matrix of outdegrees, and $A$ is the adjacency matrix. A consequence is that the sequence $(r_n)_{n \geq 1}$ completely determines the spectrum of the simple random walk on the network.Comment: 95 pages, 21 figure

What goes on when tertiary students are engaged in an online academic writing course?

The learning process is a complex one with many intertwining variables. The learners’ characteristics could be a defining factor and so is prior learning experiences and knowledge, which are the manifests of metacognitive, socio-affective and cognitive systems. A learning task engagement calls for an exertion of personal control and the fulfillment of efficiency expectations. In learning, the learner activates a number of processes such as those that concern attentional, retrieval, metacognitive and rehearsal strategies. McCombs (1988) sums up these complexities in his multimodal model of learning with certain underlying assumptions. Among them is that learning success can be manipulated. In promoting learning, the teacher can promote strategy learning such as self-directed learning. Learners if trained can select and be their own judge as to the efficacy of strategy use for the learning task. Lessard-Closton (1997) identified several basic characteristics to describe language learning strategies: they are learner-generated, they enhance language learning and competence, they may be visible or unseen and they involve the processing of information and the use of memory

A Hybrid Approach to Case Teaching

We structure case based teaching using a combination of computer-support echnology and in-class activities. We create and design an on-line learning tool, Case Study On-line (CSOL) that enables instructor to structure the delivery of teaching resources and set up assignment tasks in the system. The tool enables tasks to be set in a way that they can be completed sequentially, and learning resources can be accessed only when required by students. Upon submission of their assignments, students can promptly receive instructor’s explanations to the tasks. Follow up activities take place in class, with the objective to promote active learning. The tool was adopted over two semesters in an undergraduate economics course and surveys were conducted among the students to evaluate the effectiveness of the tool. The results of the survey were very positive, providing support to our belief that a system of well-designed case teaching delivery tool, together with classroom activities, is able to increase the level of students’ engagement and interest. The paper helps to address some concerns about teaching methods in undergraduate economics courses.Technologies-based Instruction, In-class Activities, Scaffolding, Active-based Learning