Ground-based photometry of the 21-day Neptune HD106315c

Space-based transit surveys such as K2 and TESS allow the detection of small transiting planets with orbital periods beyond 10 days. Few of these warm Neptunes are currently known around stars bright enough to allow for detailed follow-up observations dedicated to their atmospheric characterization. The 21-day period and 3.95 $R_\oplus$ planet HD106315c has been discovered based on the observation of two of its transits by K2. We have observed HD106315 using the 1.2m Euler telescope equipped with the EulerCam camera on two instances to confirm the transit using broad band photometry and refine the planetary period. Based on two observed transits of HD106315c, we detect its $\sim$1 mmag transit and obtain a precise measurement of the planetary ephemerids, which are critical for planning further follow-up observations. We have used the attained precision together with the predicted yield from the TESS mission to evaluate the potential for ground-based confirmation of Neptune-sized planets found by TESS. We find that 1-meter-class telescopes on the ground equipped with precise photometers could substantially contribute to the follow-up of 162 TESS candidates orbiting stars with magnitudes of $V \leq 14$. Out of these, 74 planets orbit stars with $V \leq 12$ and 12 planets orbit $V \leq 10$, which makes these candidates high-priority objects for atmospheric characterization with high-end instrumentation.Comment: Published in A&A letters, 4 pages, 3 figure

A Machian Model of Dark Energy

Einstein believed that Mach's principle should play a major role in finding a meaningful spacetime geometry, though it was discovered later that his field equations gave some solutions which were not Machian. It is shown, in this essay, that the kinematical $\Lambda$ models, which are invoked to solve the cosmological constant problem, are in fact consistent with Mach's ideas. One particular model in this category is described which results from the microstructure of spacetime and seems to explain the current observations successfully and also has some benefits over the conventional models. This forces one to think whether the Mach's ideas and the cosmological constant are interrelated in some way.Comment: Received an Honorable mention in the Essay Contest-2002 sponsored by the Gravity Research Foundation; A paragraph added on how the model can explain the CMB anisotropy observations; To appear in the Classical and Quantum Gravit

Making a financial time machine:a multitouch application to enable interactive 3-D visualization of distant savings goals

Financial planning and decision making for the general public continues to vex and perplex in equal measure. Whilst the tools presented by a typical desktop computer should make the task easier, the recent financial crisis confirms the increasing difficulty that people have in calculating the benefits of deferring consumption for future gains (i.e. Saving). We present an interactive concept demonstration for Microsoft SurfaceTM that tackles two of the key barriers to saving decision making. Firstly we show an interface that avoid the laborious writing down or inputting of data and instead embodies the cognitive decision of allocation of resources in a physical gesture based interface, where the scale of the investment or expenditure correlates with the scale of the gesture. Second we show how a fast-forward based animation can demonstrate the impact of small increments in savings to a long term savings goal in a strategy game-based, interactive format. The platform uses custom software (XNATM format) as opposed to the more usual WPFTM format found on Surface applications. This enables dynamic 3-D graphical icons to be used to maximize the interactive appeal of the interface. Demonstration and test trial feedback indicates that this platform can be adapted to suit the narrative of individual purchasing decisions to inform educate diverse user groups about the long term consequences of small financial decisions

Comparison of bilateral vs. unilateral-biased strength and power training interventions on measures of physical performance in elite youth soccer players

The aim of the present study was to compare the effects of bilateral and unilateral-biased strength and power training programs on measures of physical performance in male youth soccer players. Twenty-three elite youth players (age: 17.6 1.2 years) were randomly assigned to either a unilateral (n = 11) or a bilateral (n = 12) group, who completed a strength and power intervention, twice per week for 6-weeks. The unilateral group completed rear foot elevated split squats (RFESS), single leg countermovement jumps (SLCMJ), single leg drop jumps (SLDJ) and single leg broad jumps (SLBJ). The bilateral group intervention performed back squats, countermovement jumps (CMJ), drop jumps (DJ) and broad jumps (BJ). A 2 x 2 repeated measures ANOVA showed no between-group differences. However, within-group differences were evident. The bilateral training group showed significant (p < 0.05) improvements in back squat strength (d = 1.27; %Δ = 26.01), RFESS strength (d = 1.64; %Δ = 23.34), BJ (d = 0.76; %Δ = 5.12), 10 m (d = -1.17; %Δ = 4.29) and 30 m (d = -0.88; %Δ = 2.10) performance. The unilateral group showed significant (p < 0.05) improvements in RFESS strength (d = 1.40; %Δ = 33.29), SLCMJ on the left leg (d = 0.76; %Δ = 9.84), SLBJ on the left leg (d = 0.97; %Δ = 6.50), 10 m (d = -1.50; %Δ = 5.20), and 505 on the right leg (d = -0.78; %Δ = 2.80). Standardised mean differences showed that bilateral training favoured improvements in back squat strength and unilateral training favoured improvements in RFESS strength, SLDJ on the right leg and 505 on the right leg. These results show that although both training interventions demonstrated trivial to large improvements in physical performance, the notion of training specificity was evident with unilateral training showing greater improvements in unilateral test measures

Reprint of: The potential role of desalination in managing flood risks from dam overflows: the case of Sydney, Australia

© 2016 Elsevier Ltd Shifting climate patterns are causing extreme drought and flooding across the globe. This combined with the world's burgeoning population and insatiable thirst for water requires water service providers to think differently about the limited resources they manage. In Australia, the severe drought at the beginning of the century caused dams to fall to record levels. In response, many state governments invested heavily in rain-independent supplies such as desalination to augment and diversify traditional sources. However, extreme rainfall soon followed the drought, filled reservoirs and caused flooding in many locations leaving billions of dollars worth of damage and new water infrastructure standing idle. This is the case in Sydney, where the new desalination plant is still not used and the potential for major flooding has raised concerns over the safety of the large population downstream of the dam. This paper explores the growing need to understand the relationship between drought, flooding and infrastructure optimisation. The paper focuses on Sydney to illustrate the application of a system dynamics model. The new model explores options for raising the dam wall, offering airspace to assist flood protection, in contrast to options to lower the dam full supply level and utilise idle desalination capacity to fill the water security gap created. The illustrative results, using publicly available data, find that by lowering the dam water levels and operating desalination, significant flood protection can be achieved at a similar cost to raising the dam wall. The paper demonstrates the importance of optimising existing and new water resources for multiple purposes and how system dynamics modelling can assist water service providers in these complex investigations

Effect of Radiant Barrier Technology on Summer Attic Heat Load in South Texas

The objective of the study was to experimentally evaluate the performance of radiant barriers in single-family occupied housing units in South Texas. Ceiling heat fluxes, attic air temperatures, indoor air temperatures, ambient air temperatures. roof temperatures, and solar radiation were measured. Results of the radiant barrier experiment using two side-by-side 600 ft2 units are presented. Attic fiberglass insulation of nominal R-11 was installed in the two apartments when the units were last remodeled in 1974. The test houses responded similarly to weather variations, that is, attic temperature and heat flux profiles were similar in magnitude prior to the retrofit. Residents of the housing units were asked to set the thermostats at 76°F. Data were analyzed for periods of time which had the greatest attic temperatures (11 a.m. - 11 p.m.) and for which the indoor temperature differences were less than 1 percent. The results showed that radiant barriers reduced ceiling heat loads (on daily basis) by an average of 60 percent

Особливості зачину актів купівлі-продажу (на матеріалі Пирятинських міських книг)

У статті розглянуто особливості структурних компонентів початкового протоколу актів купівлі-продажу в українській мові кінця ХVІІ – другої третини ХVІІІ ст. На численних прикладах проілюстровано специфічні ознаки власне пирятинських актів, а також виявлено спільні риси, характерні для тогочасного діловодства взагалі

KMOS LENsing Survey (KLENS) : morpho-kinematic analysis of star-forming galaxies at z∼2z \sim 2

We present results from the KMOS lensing survey-KLENS which is exploiting gravitational lensing to study the kinematics of 24 star forming galaxies at $1.4<z<3.5$ with a median mass of $\rm log(M_\star/M_\odot)=9.6$ and median star formation rate (SFR) of $\rm 7.5\,M_\odot\,yr^{-1}$. We find that 25% of these low-mass/low-SFR galaxies are rotation dominated, while the majority of our sample shows no velocity gradient. When combining our data with other surveys, we find that the fraction of rotation dominated galaxies increases with the stellar mass, and decreases for galaxies with a positive offset from the main sequence. We also investigate the evolution of the intrinsic velocity dispersion, $\sigma_0$, as a function of the redshift, $z$, and stellar mass, $\rm M_\star$, assuming galaxies in quasi-equilibrium (Toomre Q parameter equal to 1). From the $z-\sigma_0$ relation, we find that the redshift evolution of the velocity dispersion is mostly expected for massive galaxies ($\rm log(M_\star/M_\odot)>10$). We derive a $\rm M_\star-\sigma_0$ relation, using the Tully-Fisher relation, which highlights that a different evolution of the velocity dispersion is expected depending on the stellar mass, with lower velocity dispersions for lower masses, and an increase for higher masses, stronger at higher redshift. The observed velocity dispersions from this work and from comparison samples spanning $0<z<3.5$ appear to follow this relation, except at higher redshift ($z>2$), where we observe higher velocity dispersions for low masses ($\rm log(M_\star/M_\odot)\sim 9.6$) and lower velocity dispersions for high masses ($\rm log(M_\star/M_\odot)\sim 10.9$) than expected. This discrepancy could, for instance, suggest that galaxies at high-$z$ do not satisfy the stability criterion, or that the adopted parametrisation of the specific star formation rate and molecular properties fail at high redshift.Comment: Accepted for publication in A&A, 21 pages, 10 figure

Hydrodynamic and magnetohydrodynamic computations inside a rotating sphere

Numerical solutions of the incompressible magnetohydrodynamic (MHD) equations are reported for the interior of a rotating, perfectly-conducting, rigid spherical shell that is insulator-coated on the inside. A previously-reported spectral method is used which relies on a Galerkin expansion in Chandrasekhar-Kendall vector eigenfunctions of the curl. The new ingredient in this set of computations is the rigid rotation of the sphere. After a few purely hydrodynamic examples are sampled (spin down, Ekman pumping, inertial waves), attention is focused on selective decay and the MHD dynamo problem. In dynamo runs, prescribed mechanical forcing excites a persistent velocity field, usually turbulent at modest Reynolds numbers, which in turn amplifies a small seed magnetic field that is introduced. A wide variety of dynamo activity is observed, all at unit magnetic Prandtl number. The code lacks the resolution to probe high Reynolds numbers, but nevertheless interesting dynamo regimes turn out to be plentiful in those parts of parameter space in which the code is accurate. The key control parameters seem to be mechanical and magnetic Reynolds numbers, the Rossby and Ekman numbers (which in our computations are varied mostly by varying the rate of rotation of the sphere) and the amount of mechanical helicity injected. Magnetic energy levels and magnetic dipole behavior are exhibited which fluctuate strongly on a time scale of a few eddy turnover times. These seem to stabilize as the rotation rate is increased until the limit of the code resolution is reached.Comment: 26 pages, 17 figures, submitted to New Journal of Physic