Assessment of alternative strategies for sludge disposal into deep ocean basins off Southern California

The general framework of engineering alternatives for regional ocean sludge disposal is well described in a report by Raksit, and will not be repeated here. The various ocean disposal alternatives are less costly than all land-disposal and incineration/pyrolysis systems studied. Even though ocean sludge disposal is currently contrary to both state and federal regulations, it is hoped that this study will advance our scientific and engineering knowledge of the behavior and effects of sludge discharge in deep water, in case the regulatory policy is reexamined in the future. With this report we hope we have demonstrated the potential and difficulties of some new modeling techniques for predicting the effects of sludge discharge in the ocean. In the future. we believe it will be possible to formulate policy of ocean sludge discharges with much better case-by-case predictions of impacts for comparison with other alternatives (such as land disposal). not only for the Los Angeles/Orange County areas, but for all coastal urban areas

Understanding how children are coping with climate change anxiety by exploring coping strategies and supportive interventions.

Climate change presents a significant threat to both the planet and human prosperity which impacts our physical health and mental well-being. There is an imminent requirement for significant global action. This means (a) our children have been born into unprecedented times and (b) as future adults, they will find themselves facing the major consequences of climate change. These can negatively affect their mental health and well-being. This paper reports the effect of climate anxiety on this population group through an exploration of coping strategies and supportive interventions. Empowering children to engage in climate action has been identified as a coping strategy. Whilst equipping them with knowledge and resources on climate change and providing safe spaces and experiences in nature are identified as supportive interventions. However, further empirical research evidence is needed to determine the next steps to address the extent of the impact of climate anxiety and prepare our children for the future

Repeated bouts of aerobic exercise lead to reductions in skeletal muscle free radical generation and nuclear factor ΚB activation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65978/1/jphysiol.2008.155382.pd

Dehydration and ionic conductance quantization in nanopores

There has been tremendous experimental progress in the last decade in identifying the structure and function of biological pores (ion channels) and fabricating synthetic pores. Despite this progress, many questions still remain about the mechanisms and universal features of ionic transport in these systems. In this paper, we examine the use of nanopores to probe ion transport and to construct functional nanoscale devices. Specifically, we focus on the newly predicted phenomenon of quantized ionic conductance in nanopores as a function of the effective pore radius - a prediction that yields a particularly transparent way to probe the contribution of dehydration to ionic transport. We study the role of ionic species in the formation of hydration layers inside and outside of pores. We find that the ion type plays only a minor role in the radial positions of the predicted steps in the ion conductance. However, ions with higher valency form stronger hydration shells, and thus, provide even more pronounced, and therefore, more easily detected, drops in the ionic current. Measuring this phenomenon directly, or from the resulting noise, with synthetic nanopores would provide evidence of the deviation from macroscopic (continuum) dielectric behavior due to microscopic features at the nanoscale and may shed light on the behavior of ions in more complex biological channels.Comment: 13 pages, 10 figure

Towards a theory of conceptual design for software

Concepts are the building blocks of software systems. They are not just subjective mental constructs, but are objective features of a system's design: increments of functionality that were consciously introduced by a designer to serve particular purposes. This essay argues for viewing the design of software in terms of concepts, with their invention (or adoption) and refinement as the central activity of software design. A family of products can be characterized by arranging concepts in a dependence graph from which coherent concept subsets can be extracted. Just as bugs can be found in the code of a function prior to testing by reviewing the programmer's argument for its correctness, so flaws can be found in a software design by reviewing an argument by the designer. This argument consists of providing, for each concept, a single compelling purpose, and demonstrating how the concept fulfills the purpose with an archetypal scenario called an 'operational principle'. Some simple conditions (primarily in the relationship between concepts and their purposes) can then be applied to reveal flaws in the conceptual design.SUTD-MIT International Design Centre (IDC

The Resolved Structure and Dynamics of an Isolated Dwarf Galaxy: A VLT and Keck Spectroscopic Survey of WLM

We present spectroscopic data for 180 red giant branch stars in the isolated dwarf irregular galaxy WLM. Observations of the Calcium II triplet lines in spectra of RGB stars covering the entire galaxy were obtained with FORS2 at the VLT and DEIMOS on Keck II allowing us to derive velocities, metallicities, and ages for the stars. With accompanying photometric and radio data we have measured the structural parameters of the stellar and gaseous populations over the full galaxy. The stellar populations show an intrinsically thick configuration with $0.39 \leq q_{0} \leq 0.57$. The stellar rotation in WLM is measured to be $17 \pm 1$ km s$^{-1}$, however the ratio of rotation to pressure support for the stars is $V/\sigma \sim 1$, in contrast to the gas whose ratio is seven times larger. This, along with the structural data and alignment of the kinematic and photometric axes, suggests we are viewing WLM as a highly inclined oblate spheroid. Stellar rotation curves, corrected for asymmetric drift, are used to compute a dynamical mass of $4.3\pm 0.3\times10^{8}$M$_{\odot}$ at the half light radius ($r_{h} = 1656 \pm 49$ pc). The stellar velocity dispersion increases with stellar age in a manner consistent with giant molecular cloud and substructure interactions producing the heating in WLM. Coupled with WLM's isolation, this suggests that the extended vertical structure of its stellar and gaseous components and increase in stellar velocity dispersion with age are due to internal feedback, rather than tidally driven evolution. These represent some of the first observational results from an isolated Local Group dwarf galaxy which can offer important constraints on how strongly internal feedback and secular processes modulate SF and dynamical evolution in low mass isolated objects.Comment: 14 Pages, 17 figures, 3 tables. Accepted for publication in Ap

The Millimeter Astronomy Legacy Team 90 GHz (MALT90) Pilot Survey

We describe a pilot survey conducted with the Mopra 22-m radio telescope in preparation for the Millimeter Astronomy Legacy Team Survey at 90 GHz (MALT90). We identified 182 candidate dense molecular clumps using six different selection criteria and mapped each source simultaneously in 16 different lines near 90 GHz. We present a summary of the data and describe how the results of the pilot survey shaped the design of the larger MALT90 survey. We motivate our selection of target sources for the main survey based on the pilot detection rates and demonstrate the value of mapping in multiple lines simultaneously at high spectral resolution.Comment: Accepted to ApJS. 23 pages and 16 figures. Full resolution version with an appendix showing all the data (12.1 MB) is available at http://malt90.bu.edu/publications/Foster_2011_Malt90Pilot.pd

Habitat structure shapes temperate reef assemblages across regional environmental gradients

Intertidal artificial habitats are proliferating, but are generally simpler in structure and host lower biodiversity than natural rocky reefs. Eco-engineering aims to enhance the biodiversity of coastal infrastructure, often through physical structural modifications that mimic topographic properties of natural shores. Relationships between biotic assemblages and structural properties of natural and artificial reefs have been extensively studied at sampling scales of up to 1 m2. But evidence that quantified local structural variation has an appreciable influence on biotic assemblages, at a shore-wide scale across regional environmental gradients, is lacking. Here we addressed this knowledge gap with an observational study at 32 natural and artificial intertidal reef sites in Wales, UK. We used multivariate community analysis and permutation tests to examine associations between local physical structure, regional environmental variables and sessile biotic assemblages. A potential influence of local habitat structure on assemblage composition was evident across regional-scale environmental gradients. Compared to natural sites, artificial reefs had lower taxonomic richness, distinct and more variable assemblage composition, and different physical structure. After removing the effect of habitat (natural or artificial), canonical correspondence analysis showed that environmental variables (wave exposure, sea surface temperature and salinity variation), along with two metrics of physical structure (standard deviation in log-transformed detrended roughness and skewness of surface verticality, both at 0.5 m scale), explained 40 % of the variation in assemblage composition among sites. The two structural metrics independently explained 14.5 % of the variation. Associations identified between individual taxa and environmental variables indicated that sites with a higher proportion of horizontal surfaces hosted more canopy macroalgae, which in turn support other algae and invertebrates. Our findings provide evidence to inform scaling-up of structural eco-engineering interventions from experimental contexts to enhance the biodiversity of coastal infrastructure across regional extents

Regularization of the Coulomb scattering problem

Exact solutions of the Schr\"odinger equation for the Coulomb potential are used in the scope of both stationary and time-dependent scattering theories in order to find the parameters which define regularization of the Rutherford cross-section when the scattering angle tends to zero but the distance r from the center remains fixed. Angular distribution of the particles scattered in the Coulomb field is investigated on the rather large but finite distance r from the center. It is shown that the standard asymptotic representation of the wave functions is not available in the case when small scattering angles are considered. Unitary property of the scattering matrix is analyzed and the "optical" theorem for this case is discussed. The total and transport cross-sections for scattering of the particle by the Coulomb center proved to be finite values and are calculated in the analytical form. It is shown that the considered effects can be essential for the observed characteristics of the transport processes in semiconductors which are defined by the electron and hole scattering in the fields of the charged impurity centers.Comment: 20 pages, 6 figure