Constraining an Expanding Locally Anisotropic metric from the Pioneer anomaly

It is discussed the possibility of a fine-tuneable contribution to the two way Doppler acceleration either towards, either outwards the Sun for heliocentric distances above 20 AU by considering a background described by an Expanding Locally Anisotropic (ELA) metric. This metric encodes both the standard local Schwarzschild gravitational effects and the cosmological Universe expansion effects allowing simultaneously to fine-tune other gravitational effects at intermediate scales, which may be tentatively interpreted as a covariant parameterization of either cold dark matter either gravitational interaction corrections. Are derived bounds for the ELA metric functional parameter by considering the bounds on the deviation from standard General Relativity imposed by the current updated limits for the Pioneer anomaly, taking in consideration both the natural outgassing and on-board radiation pressure, resulting in an average Doppler acceleration outwards the Sun of a_p = +0.4^{+2.1}_{-2.0} x 10^{-10} (m/s^2). It is also computed the mass-energy density for the ELA metric within the bounds obtained and are discussed the respective contributions to the cosmological mass-energy density which, for compatibility with the Lambda-CDM model, are included in Omega_{CDM}.Comment: 22 pages; 6 figures; based on arXiv:1102.2061 with updated estimative for Pioneer anomal

Creating cultural change in education: A proposal for a continuum for evaluating the effectiveness of sustainable schools implementation strategies in Australia

Networks are increasingly recognised as advantageous when creating and embedding cultural change within organisations. This paper explores andproblematises ideas around networks for education for sustainability (EfS), Australian Sustainable Schools Initiative (AuSSI), a national, whole-school approach to EfS. In three Australian states - New South Wales, Victoria and Queensland – AuSSI has been implemented in different ways. In examining the use of products, facilitators and networks to embed initiatives such as AuSSI in Australian schools, we propose a “continuum of cultural change strategies” as a framework for thinking about each of these approaches to creating organisational and cultural change for sustainability. We anticipate that such a framework may assist where choices need to be made in relation to the kinds of capacity building processes that might best achieve “deep and wide” change within schools hoping to engender significant cultural change

Streaming velocities as a dynamical estimator of Omega

It is well known that estimating the pairwise velocity of galaxies, v_{12}, from the redshift space galaxy correlation function is difficult because this method is highly sensitive to the assumed model of the pairwise velocity dispersion. Here we propose an alternative method to estimate v_{12} directly from peculiar velocity samples, which contain redshift-independent distances as well as galaxy redshifts. In contrast to other dynamical measures which determine beta = sigma_8 x Omega^{0.6}, our method can provide an estimate of (sigma_8)^2 x Omega^{0.6} for a range of sigma_8 (here Omega is the cosmological mass density parameter while sigma_8 is the standard normalization parameter for the spectrum of matter density fluctuations). We demonstrate how to measure this quantity from realistic catalogues.Comment: 8 pages of text, 4 figures Subject headings: Cosmology: theory - observation - peculiar velocities: large scale flows Last name of one of the authors was misspelled. It is now corrected. Otherwise the manuscript is identical to its original versio

An Expanding Locally Anisotropic (ELA) Metric Describing Matter in an Expanding Universe

It is suggested an expanding locally anisotropic metric (ELA) ansatz describing matter in a flat expanding universe which interpolates between the Schwarzschild (SC) metric near point-like central bodies of mass 'M' and the Robertson-Walker (RW) metric for large radial coordinate: 'ds^2=Z(cdt)2 - 1/Z (dr1-(Hr1/c) Z^(alpha/2+1/2)(cdt))^2-r1^2 dOmega', where 'Z=1-U' with 'U=2GM/(c^2r1)', 'G' is the Newton constant, 'c' is the speed of light, 'H=H(t)=\dot(a)/a' is the time-dependent Hubble rate, 'dOmega=dtheta^2+sin^2(theta) dvarphi^2' is the solid angle element, 'a' is the universe scale factor and we are employing the coordinates 'r1=ar', being 'r' the radial coordinate for which the RW metric is diagonal. For constant exponent 'alpha=alpha0=0' it is retrieved the isotropic McVittie (McV) metric and for 'alpha=alpha0=1' it is retrieved the locally anisotropic Cosmological-Schwarzschild (SCS) metric, both already discussed in the literature. However it is shown that only for constant exponent 'alpha=alpha0> 1' exists an event horizon at the SC radius 'r1=2GM/c^2' and only for 'alpha=alpha0>= 3' space-time is singularity free for this value of the radius. These bounds exclude the previous existing metrics, for which the SC radius is a naked extended singularity. In addition it is shown that for 'alpha=alpha0>5' space-time is approximately Ricci flat in a neighborhood of the event horizon such that the SC metric is a good approximation in this neighborhood. It is further shown that to strictly maintain the SC mass pole at the origin 'r1=0' without the presence of more severe singularities it is required a radial coordinate dependent correction to the exponent 'alpha(r1)=alpha0+alpha1 '2GM/(c^2 r1)' with a negative coefficient 'alpha1<0'. The energy-momentum density, pressures and equation of state are discussed.Comment: 6 pages; 2 figures; covers some of the derivations in arXiv:0907.0847 with corrected terminology and a new discussion of the event horizon

Measuring Omega with Galaxy Streaming Velocities

The mean pairwise velocity of galaxies has traditionally been estimated from the redshift space galaxy correlation function. This method is notorious for being highly sensitive to the assumed model of the pairwise velocity dispersion. Here we propose an alternative method to estimate the streaming velocity directly from peculiar velocity samples, which contain redshift-independent distances as well as galaxy redshifts. This method can provide an estimate of $\Omega^{0.6}\sigma_8^2$ for a range of $\sigma_8$ where $\Omega$ is the cosmological density parameter, while $\sigma_8$ is the standard normalization for the power spectrum of density fluctuations. We demonstrate how to measure this quantity from realistic catalogues and identify the main sources of bias and errorsComment: Proceedings of New Worlds in Astroparticle Physics, 6 pages, 2 figure

Evidence for a low-density Universe from the relative velocities of galaxies

The motions of galaxies can be used to constrain the cosmological density parameter Omega and the clustering amplitude of matter on large scales. The mean relative velocity of galaxy pairs, estimated from the Mark III survey, indicates that Omega = 0.35 +0.35/-0.25. If the clustering of galaxies is unbiased on large scales, Omega = 0.35 +/- 0.15, so that an unbiased Einstein-de Sitter model (Omega = 1) is inconsistent with the data.Comment: 12 pages, 2 figures, to appear in the Jan.7 issue of ``Science''; In the original version, the title appeared twice. This problem has now been corrected. No other changes were mad

Improved Student Outcomes in Biological Psychology Courses Through Scaffolded Reading and Writing Assignments.

The American Psychological Association expects graduating psychology majors to be able to read and summarize complex ideas accurately, and to communicate effectively as writers. However, undergraduates often have little explicit instruction and practice in reading and summarizing academic articles, or in psychology-specific writing practices. Consequently, students’ skills as academic readers and writers often fail to meet expectations. In our large public university, writing problems were prevalent in our biological psychology classes. When asked to read and summarize primary sources, students reported that the articles were very difficult to understand, papers commonly included plagiarism, and many students withdrew from the classes. To counteract this, the instructor––first author (JG-F) consulted with an English for Academic Purposes specialist (CD-F) and we created a scaffolded series of homework assignments to help students learn how to read and summarize primary source articles. Students received guided instruction about where to find information in an article and how to take notes using their own words. To help manage the instructor’s time, she spent class time going over common errors and modeling ways to paraphrase and avoid plagiarism. A mastery approach to the homework assignments was fostered by grading several assignments on a complete/incomplete basis. Students who received the intervention had higher writing assignment grades, were more likely to persist in the classes, and were less likely to fail than those who did not receive the intervention. Most students felt that the intervention improved their ability to read and to use primary sources in their writing assignments, and thought that these skills would be transferrable to other courses

Interaction of young stellar object jets with their accretion disk

I reexamine recent observations of velocity profiles across jets blown by young stellar objects, and argue that the observations do not support the interpretation of jets rotating around their symmetry axes. Instead, I propose that the interaction of the jets with a twisted-tilted (wrapped) accretion disk can form the observed asymmetry in the jets' line of sight velocity profiles. The proposed scenario is based on two plausible assumptions. (1) There is an inclination between the jet and the outer parts of the disk; the jet is perpendicular to the inner part of the disk; Namely, there is a twisted-tilted (wrapped) disk. (2) The disk-jet interaction slows down the jet as the jet entrains mass from the disk, with larger decelaration of jet segments closer to the tilted disk. The proposed scenario can account for the basic properties of the observed velocity profiles, while having the advantage that there is no need to refer to any magnetic jet launching model, and there is no need to invoke jet rotation with a huge amount of angular momentum.Comment: Astronomy and Astrophysics, in press (contains an appendix which is not in A&A

Machine learning in nutritional follow-up research

Healthcare is one of the world’s fastest growing industries, having large volumes of data collected on a daily basis. It is generally perceived as being ‘information rich’ yet ‘knowledge poor’. Hidden relationships and valuable knowledge can be discovered in the collected data from the application of data mining techniques. These techniques are being increasingly implemented in healthcare organizations in order to respond to the needs of doctors in their daily decision-making activities. To help the decision-makers to take the best decision it is fundamental to develop a solution able to predict events before their occurrence. The aim of this project was to predict if a patient would need to be followed by a nutrition specialist, by combining a nutritional dataset with data mining classification techniques, using WEKA machine learning tools. The achieved results showed to be very promising, presenting accuracy around 91%, specificity around 97% and precision about 95%.This work has been supported by Compete: POCI-01-0145-FEDER-007043 and FCT within the Project Scope UID/CEC/00319/2013

A state-wide systems approach to embedding the learning and teaching of sustainability in teacher education

[Extract] Education systems have a key role to play in preparing future citizens to engage in sustainable living practices and help create a more sustainable world. Many schools throughout Australia have begun to develop whole-school approaches to sustainability education that are supported by national and state policies and curriculum frameworks. Pre-service teacher education, however, lags behind in the effort to build the capacity of new teachers to initiate and implement such approaches (Steele, 2010). Evidence suggests this is because there is limited or no core environmental or sustainability knowledge or pedagogy in pre- and in-service courses and programs available to teachers in a thorough and systematic fashion