SLR-derived terrestrial reference frame using the observations to LAGEOS-1/2, Starlette, Stella, and AJISAI

Currently, the contributions of Starlette, Stella, and AJISAI are not taken into account when defining the International Terrestrial Reference Frame (ITRF), despite the large amount of data collected in a long time-span. Consequently, the SLR-derived parameters and the SLR part of the ITRF are almost exclusively defined by LAGEOS-1 and LAGEOS-2. We investigate the potential of combining the observations to several SLR satellites with different orbital characteristics. Ten years of SLR data are homogeneously processed using the development version 5.3 of the Bernese GNSS Software. Special emphasis is put on orbit parameterization and the impact of LEO data on the estimation of the geocenter coordinates, Earth rotation parameters, Earth gravity field coefficients, and the station coordinates in one common adjustment procedure. We find that the parameters derived from the multi-satellite solutions are of better quality than those obtained in single satellite solutions or solutions based on the two LAGEOS satellites. A spectral analysis of the SLR network scale w.r.t. SLRF2008 shows that artifacts related to orbit perturbations in the LAGEOS-1/2 solutions, i.e., periods related to the draconitic years of the LAGEOS satellites, are greatly reduced in the combined solutions.

New library buildings: the Houston Academy of Medicine--Texas Medical Center Library.

A historical account is given of the Houston Academy of Medicine--Texas Medical Center Library within its Texas Medical Center setting in Houston, Texas. Outlined are planning, financing, and construction of the new library, which consists in part of new building and in part of renovated interiors of an old building originally completed in 1954. A concise picture is given of the new library's interiors, showing its functional success for users and employees alike. An architectural summary is appended showing gross and net footages, source of funds, costs and capacities.

Dominance of the proximal coordinate frame in determining the locations of hippocampal place cell activity during navigation.

The place-specific activity of hippocampal cells provides downstream structures with information regarding an animal's position within an environment and, perhaps, the location of goals within that environment. In rodents, recent research has suggested that distal cues primarily set the orientation of the spatial representation, whereas the boundaries of the behavioral apparatus determine the locations of place activity. The current study was designed to address possible biases in some previous research that may have minimized the likelihood of observing place activity bound to distal cues. Hippocampal single-unit activity was recorded from six freely moving rats as they were trained to perform a tone-initiated place-preference task on an open-field platform. To investigate whether place activity was bound to the room- or platform-based coordinate frame (or both), the platform was translated within the room at an "early" and at a "late" phase of task acquisition (Shift 1 and Shift 2). At both time points, CA1 and CA3 place cells demonstrated room-associated and/or platform-associated activity, or remapped in response to the platform shift. Shift 1 revealed place activity that reflected an interaction between a dominant platform-based (proximal) coordinate frame and a weaker room-based (distal) frame because many CA1 and CA3 place fields shifted to a location intermediate to the two reference frames. Shift 2 resulted in place activity that became more strongly bound to either the platform- or room-based coordinate frame, suggesting the emergence of two independent spatial frames of reference (with many more cells participating in platform-based than in room-based representations).

Still frame from the hour of death: Acute intracerebral hemorrhage on post-mortem computed tomography in a decomposed corpse

We report a case of an acute hypertensive, intracerebral hemorrhage on post-mortem computed tomography (PMCT) in a decomposed corpse. In clinical radiology, the appearance of blood on cross-sectional imaging is used to estimate the age of intracranial hemorrhage. The findings from this case indicate that characteristics of intracerebral blood on PMCT provide a still frame of the hemorrhage, as it was at the time of death. This observation suggests that the appearance of blood on PMCT may be used to estimate the age of an intracerebral hemorrhage but not to estimate the post-mortem interval.

Contribution of Starlette, Stella, and AJISAI to the SLR-derived global reference frame

The contribution of Starlette, Stella, and AJI-SAI is currently neglected when defining the International Terrestrial Reference Frame, despite a long time series of precise SLR observations and a huge amount of available data. The inferior accuracy of the orbits of low orbiting geodetic satellites is the main reason for this neglect. The Analysis Centers of the International Laser Ranging Service (ILRS ACs) do, however, consider including low orbiting geodetic satellites for deriving the standard ILRS products based on LAGEOS and Etalon satellites, instead of the sparsely observed, and thus, virtually negligible Etalons. We process ten years of SLR observations to Starlette, Stella, AJISAI, and LAGEOS and we assess the impact of these Low Earth Orbiting (LEO) SLR satellites on the SLR-derived parameters. We study different orbit parameterizations, in particular different arc lengths and the impact of pseudo-stochastic pulses and dynamical orbit parameters on the quality of the solutions. We found that the repeatability of the East and North components of station coordinates, the quality of polar coordinates, and the scale estimates of the reference are improved when combining LAGEOS with low orbiting SLR satellites. In the multi-SLR solutions, the scale and the Z component of geocenter coordinates are less affected by deficiencies in solar radiation pressure modeling than in the LAGEOS-1/2 solutions, due to substantially reduced correlations between the Z geocenter coordinate and empirical orbit parameters. Eventually, we found that the standard values of Center-of-mass corrections (CoM) for geodetic LEO satellites are not valid for the currently operating SLR systems. The variations of station-dependent differential range biases reach 52 and 25 mm for AJISAI and Starlette/Stella, respectively, which is why estimating station dependent range biases or using station-dependent CoM, instead of one value for all SLR stations, is strongly recommended.This clearly indicates that the ILRS effort to produce CoM corrections for each satellite, which are site-specific and depend on the system characteristics at the time of tracking,is very important and needs to be implemented in the SLR data analysis.

A physical approach on flood risk vulnerability of buildings

The design of efficient hydrological risk mitigation strategies and their subsequent implementation relies on a careful vulnerability analysis of the elements exposed. Recently, extensive research efforts were undertaken to develop and refine empirical relationships linking the structural vulnerability of buildings to the impact forces of the hazard processes. These empirical vulnerability functions allow estimating the expected direct losses as a result of the hazard scenario based on spatially explicit representation of the process patterns and the elements at risk classified into defined typological categories. However, due to the underlying empiricism of such vulnerability functions, the physics of the damage-generating mechanisms for a well-defined element at risk with its peculiar geometry and structural characteristics remain unveiled, and, as such, the applicability of the empirical approach for planning hazard-proof residential buildings is limited. Therefore, we propose a conceptual assessment scheme to close this gap. This assessment scheme encompasses distinct analytical steps: modelling (a) the process intensity, (b) the impact on the element at risk exposed and (c) the physical response of the building envelope. Furthermore, these results provide the input data for the subsequent damage evaluation and economic damage valuation. This dynamic assessment supports all relevant planning activities with respect to a minimisation of losses, and can be implemented in the operational risk assessment procedure.

How parties frame social citizenship and the inclusion of immigrants in Germany, Switzerland and the United Kingdom

Recent research on the transformation of West European party systems emphasises that cultural issues such as immigration have gained in importance besides the traditional socio-economic cleavage. While this literature shows that parties address not only cultural but also economic is-sues, it has paid less attention on whether parties combine cultural and economic issues. In this paper we focus on immigrants’ social rights by analysing if and how mainstream parties combine immigration and redistributive issues. Drawing on Faist (1995), we distinguish three different perspectives how political actors, here mainstream parties, might react to the welfare chauvinist claims that aim to restrict immigrants’ social rights. Our analysis relies on party manifestos in Germany, Switzerland and the United Kingdom between 1999 and 2011. The results of the anal-ysis indicate that variation is found among party families, in particular among the left. Even though the purpose of the paper is not to ‘prove’ that the populist challenge explains how the mainstream left-wing parties behave, the results allow nonetheless for interpreting mainstream parties’ strategic combination of welfare and immigration issues as a response to anti-immigration and anti-integration issues raised by populist challengers.

Investigating policy processes: The Governance Analytical Frame-work (GAF)

Societies develop ways of making decisions regarding collective problems, thereby creating norms, rules, and institutions; this is what governance is about. In policy research, governance has become an important focus of attention; but debates show a lack of clarity at the conceptual level and a confusion between the use of the concept for prescriptive and analytical purposes. The present article is based on the hypothesis that using a clarified, non-normative governance perspective in policy research can contribute to an improved understanding of political processes, including formal and unrecognised ones, those embedded in larger and smaller social systems, as well as both vertical and horizontal political arrangements. The paper is the result of a collaborative engagement with the concept of governance within several networks, leading to the development of the Governance Analytical Framework (GAF). The GAF is a practical methodology for investigating governance processes, based on five analytical tools: problems, actors, social norms, processes, and nodal points. Besides describing the conceptual sources and analytical purpose of these five tools, the paper presents examples of how the GAF can be operationalised.

Analytical frame for public policy implementation

"I don't think we truly understand how to implement. What does it mean to truly implement? Not the command center type that our culture is very good at, but a thorough planned systematic approach" (HP, 9.28.2011). This important question is asked by a clinician who works in a health care setting and who has experienced the implementation of a public policy. This case study applied the lessons learned from three generations of public policy research to a health care setting. As a result of the study an analytical frame was created as a guide to assess an organization's readiness for the implementation of a public policy.^