Choosing friends carefully: allies for critical computing

In this paper, we argue firstly that researchers in critical computing should address the specific information and communication technology (ICT) needs and activities of those agencies concerned with emancipatory issues. Secondly, we argue that a critical perspective, explicitly foregrounding empowerment and emancipatory concerns, forms a basis for emphasising the practice of individuals, groups and organsations , rather than purely focusing on organisational form in social action. We discuss this context of social action, identifying some relevant ICT-related challenges. We identify three themes that highlight factors that differentiate ICT support for social action groups from the setting of conventional business and service organisations: Free / Libre Open- Source Software, techniques and technologies for engagement through storytelling, and learning and evaluation in social action.</p

Teaching Proficiency Through Reading and Storytelling (Tprs) as a Technique to Foster Students\u27 Speaking Skill

Teaching Proficiency through Reading and Storytelling (TPRS) is quite essential to improve EFL learners\u27 speaking ability. It can be done successfully by means of the basic concept of TPRS known as comprehensible input in second language acquisition (SLA). This paper presents a study on learners\u27 speaking ability through TPRS making use of three important steps; Showing, Telling, and Reading. This is a quantitative study using quasi-experimental as the two intact groups are used; experimental and control group. The data are obtained from pre-test, post-test and questionnaires viewed from both students\u27 and teachers\u27 perspective. The data from pre-test and post-test are analyzed by using independent sample t-test. The experimental and control are ascertained to be homogenous in term of English performance from the pre-test analysis. The post-test are carried out from both groups after the treatment and the the result of the test are compared in order to prove if the null hypothesis is rejected indicating that there is significant difference performance between the two groups. The result of the study is expected to be beneficial for English teachers, EFL learners, and further researchers

Serendipitous Science from the K2 Mission

The K2 mission is a repurposed use of the Kepler spacecraft to perform high-precision photometry of selected fields in the ecliptic. We have developed an aperture photometry pipeline for K2 data which performs dynamic automated aperture mask selection, background estimation and subtraction, and positional decorrelation to minimize the effects of spacecraft pointing jitter. We also identify secondary targets in the K2 "postage stamps" and produce light curves for those targets as well. Pipeline results will be made available to the community. Here we describe our pipeline and the photometric precision we are capable of achieving with K2, and illustrate its utility with asteroseismic results from the serendipitous secondary targets.Comment: 6 pages, 9 figures To appear in IAU Focus Meeting 17, "Advances in Stellar Physics from Asteroseismology", ed. Piero Benvenut

Are all hosts created equal? Partitioning host species contributions to parasite persistence in multihost communities

Many parasites circulate endemically within communities of multiple host species. To understand disease persistence within these communities, it is essential to know the contribution each host species makes to parasite transmission and maintenance. However, quantifying those contributions is challenging. We present a conceptual framework for classifying multihost sharing, based on key thresholds for parasite persistence. We then develop a generalized technique to quantify each species’ contribution to parasite persistence, allowing natural systems to be located within the framework. We illustrate this approach using data on gastrointestinal parasites circulating within rodent communities and show that, although many parasites infect several host species, parasite persistence is often driven by just one host species. In some cases, however, parasites require multiple host species for maintenance. Our approach provides a quantitative method for differentiating these cases using minimal reliance on system-specific parameters, enabling informed decisions about parasite management within poorly understood multihost communities

Reevaluating evaluative conditioning: A nonassociative explanation of conditioning effects in the visual evaluative conditioning paradigm

In 2 studies, the authors investigated whether evaluative conditioning (EC) is an associative phenomenon. Experiment 1 compared a standard EC paradigm with nonpaired and no-treatment control conditions. EC effects were obtained only when the conditioned stimulus (CS) and unconditioned stimulus (UCS) were rated as perceptually similar. However, similar EC effects were obtained in both control groups. An earlier failure to obtain EC effects was reanalyzed in Experiment 2. Conditioning-like effects were found when comparing a CS with the most perceptually similar UCSs used in the procedure but not when analyzing a CS rating with respect to the UCS with which it was paired during conditioning. The implications are that EC effects found in many studies are not due to associative learning and that the special characteristics of EC (conditioning without awareness and resistance to extinction) are probably nonassociative artifacts of the EC paradigm

Fluctuation-enhanced electric conductivity in electrolyte solutions

In this letter we analyze the effects of an externally applied electric field on thermal fluctuations for a fluid containing charged species. We show in particular that the fluctuating Poisson-Nernst-Planck equations for charged multispecies diffusion coupled with the fluctuating fluid momentum equation, result in enhanced charge transport. Although this transport is advective in nature, it can macroscopically be represented as electrodiffusion with renormalized electric conductivity. We calculate the renormalized electric conductivity by deriving and integrating the structure factor coefficients of the fluctuating quantities and show that the renormalized electric conductivity and diffusion coefficients are consistent although they originate from different noise terms. In addition, the fluctuating hydrodynamics approach recovers the electrophoretic and relaxation corrections obtained by Debye-Huckel-Onsager theory, and provides a quantitative theory that predicts a non-zero cross-diffusion Maxwell-Stefan coefficient that agrees well with experimental measurements. Finally, we show that strong applied electric fields result in anisotropically enhanced velocity fluctuations and reduced fluctuations of salt concentrations.Comment: 12 pages, 1 figur

Low Mach Number Fluctuating Hydrodynamics for Electrolytes

We formulate and study computationally the low Mach number fluctuating hydrodynamic equations for electrolyte solutions. We are interested in studying transport in mixtures of charged species at the mesoscale, down to scales below the Debye length, where thermal fluctuations have a significant impact on the dynamics. Continuing our previous work on fluctuating hydrodynamics of multicomponent mixtures of incompressible isothermal miscible liquids (A. Donev, et al., Physics of Fluids, 27, 3, 2015), we now include the effect of charged species using a quasielectrostatic approximation. Localized charges create an electric field, which in turn provides additional forcing in the mass and momentum equations. Our low Mach number formulation eliminates sound waves from the fully compressible formulation and leads to a more computationally efficient quasi-incompressible formulation. We demonstrate our ability to model saltwater (NaCl) solutions in both equilibrium and nonequilibrium settings. We show that our algorithm is second-order in the deterministic setting, and for length scales much greater than the Debye length gives results consistent with an electroneutral/ambipolar approximation. In the stochastic setting, our model captures the predicted dynamics of equilibrium and nonequilibrium fluctuations. We also identify and model an instability that appears when diffusive mixing occurs in the presence of an applied electric field.Comment: 37 pages, 5 figure

Topological Optimization of the Evaluation of Finite Element Matrices

We present a topological framework for finding low-flop algorithms for evaluating element stiffness matrices associated with multilinear forms for finite element methods posed over straight-sided affine domains. This framework relies on phrasing the computation on each element as the contraction of each collection of reference element tensors with an element-specific geometric tensor. We then present a new concept of complexity-reducing relations that serve as distance relations between these reference element tensors. This notion sets up a graph-theoretic context in which we may find an optimized algorithm by computing a minimum spanning tree. We present experimental results for some common multilinear forms showing significant reductions in operation count and also discuss some efficient algorithms for building the graph we use for the optimization

The Withdrawal TIME of the Antibiotic of Zinc Bacitracin Towards Its Residue in Broiler

Genetic development of broiler is growing rapidly. Nowadays, broiler is slaughtered at the ages of 29 days rather than 35 days. Rapid growth is usually coupled by an immune deficiencies of broiler, therefore such feed additives as antibiotics is necessary to promote growth and improve endurance of the broiler. The purpose of this research was to investigate the amount of residue of Zinc bacitracin antibiotics in the thigh meat, breast meat, liver, and kidney of the broilers; and to determine the withdrawal time between the discontinuation of the antibiotic of the Zinc bacitracin and the slaughter of the broiler to eliminate or to reduce that residue so that the product of the broiler was safe for human consumption. The research was conducted at Sekolah Tinggi Penyuluhan Pertanian (STPP) Gowa. The broilers used in this study was strain Cobb SR 707, aged 29 days (unsexed), and were obtained from the local broiler farm. The ration containing the antibiotics of the Zinc bacitracin was terminated at day 0, 3, 6, and 9 before slaughtering. The bacteria used to test the dilution sensitivity was Staphylococcus aureus (105-108 colony mL-1). The transmittance reading of the sample solution from the Spectrophotometer was inputted into standard curve generated by from pure antibiotics to determine the antibiotics residue in the samples. The results were then compared with the value of SNI Number: 01-6366-2000 of year 2000. The data were analyzed descriptively and with a non linier regression analysis. The results revealed that the level of the Zinc bacitracin residue decreased following the duration of the cessation of the Zinc bacitracin antibiotic treatment. The antibiotic residue in the sample was smaller than that set in the standards (SNI, 2000) so that the broiler products were safe for human consumption