435 research outputs found
Votemandering: Strategies and Fairness in Political Redistricting
Gerrymandering, the deliberate manipulation of electoral district boundaries
for political advantage, is a persistent issue in U.S. redistricting cycles.
This paper introduces and analyzes a new phenomenon, 'votemandering'- a
strategic blend of gerrymandering and targeted political campaigning, devised
to gain more seats by circumventing fairness measures. It leverages accurate
demographic and socio-political data to influence voter decisions, bolstered by
advancements in technology and data analytics, and executes better-informed
redistricting. Votemandering is established as a Mixed Integer Program (MIP)
that performs fairness-constrained gerrymandering over multiple election
rounds, via unit-specific variables for campaigns. To combat votemandering, we
present a computationally efficient heuristic for creating and testing district
maps that more robustly preserve voter preferences. We analyze the influence of
various redistricting constraints and parameters on votemandering efficacy. We
explore the interconnectedness of gerrymandering, substantial campaign budgets,
and strategic campaigning, illustrating their collective potential to generate
biased electoral maps. A Wisconsin State Senate redistricting case study
substantiates our findings on real data, demonstrating how major parties can
secure additional seats through votemandering. Our findings underscore the
practical implications of these manipulations, stressing the need for informed
policy and regulation to safeguard democratic processes
Change in subunit composition of the iron protein of nitrogenase from Rhodospirillum rubrum during activation and inactivation of iron protein
Orthogonal binding and displacement of different guest types using a coordination cage host with cavity-based and surface-based binding sites
The octanuclear Co(II) cubic coordination cage system H (or HW if it bears external water-solubilising substituents) has two types of binding site for guests. These are (i) the partially-enclosed central cavity where neutral hydrophobic organic species can bind, and (ii) the six 'portals' in the centres of each of the faces of the cubic cage where anions bind via formation of a network of CHâŻX hydrogen bonds between the anion and CH units on the positively-charged cage surface, as demonstrated by a set of crystal structures. The near-orthogonality of these guest binding modes provides the basis for an unusual dual-probe fluorescence displacement assay in which either a cavity-bound fluorophore (4-methyl-7-amino-coumarin, MAC; λem = 440 nm), or a surface-bound anionic fluorophore (fluorescein, FLU; λem = 515 nm), is displaced and has its emission âswitched onâ according to whether the analyte under investigation is cavity-binding, surface binding, or a combination of both. A completely orthogonal system is demonstrated based using a Hw/MAC/FLU combination: addition of the anionic analyte ascorbate displaced solely FLU from the cage surface, increasing the 515 nm (green) emission component, whereas addition of a neutral hydrophobic guest such as cyclooctanone displaced solely MAC from the cage central cavity, increasing the 440 nm (blue) emission component. Addition of chloride results in some release of both components, and an intermediate colour change, as chloride is a rare example of a guest that shows both surface-binding and cavity-binding behaviour. Thus we have a colourimetric response based on differing contributions from blue and green emission components in which the specific colour change signals the binding mode of the analyte. Addition of a fixed red emission component from the complex [Ru(bipy)3]2+ (Ru) provides a baseline colour shift of the overall colour of the luminescence closer to neutral, meaning that different types of guest binding result in different colour changes which are easily distinguishable by eye
ADP-ribosylation of dinitrogenase reductase from Clostridium pasteurianum prevents its inhibition of nitrogenase from Azotobacter vinelandii
Innovation in the Medical Design Industry through the Use of Thematic Framing
The healthcare industry struggles with the creation of radical innovations due to many different stakeholders with competing interests. This research project aimed at the development of a methodology that supports medical designers to create innovations by using deep human insights. As a starting point, we used a four-layer model of insights into human needs and aspirations, ranging from solutions (âwhatâ) and scenarios (âhowâ), to goals and themes (âwhyâ). To transform this model into a design methodology, we iteratively developed and evaluated the methodology together with medical designers in a real world design setting. As a result, we distinguished five stages of a so called âThematic Framingâ process: (1) current frame, (2) needs and aspirations, (3) themes, (4.a) new frames, (4.b) ideas for solutions, and (5) opportunities. The added value of the methodology is that the âwhyâ level is divided in whyâs on the goal level â within the design context â and whyâs at the theme level that will be analysed outside the design context. Moving outside the design context allows for mapping the pattern of the theme to solutions in other contexts; this can create metaphors that can subsequently form a bridge to new frames and solutions
One guest or two? A crystallographic and solution study of guest binding in a cubic coordination cage
A crystallographic investigation of a series of host/guest complexes in which smallâmolecule organic guests occupy the central cavity of an approximately cubic M 8 L 12 coordination cage has revealed some unexpected behaviour. Whilst some guests form 1:1 HâąG complexes as we have seen before, an extensive family of bicyclic guests â including some substituted coumarins and various saturated analogues â form 1:2 HâąG 2 complexes in the solid state, despite the fact that solution titrations are consistent with 1:1 complex formation, and the combined volume of the pair of guests significantly exceeds the Rebek 55±9% packing for optimal guest binding, with packing coefficients of up to 87%. Reâexamination of solution titration data for guest binding in two cases showed that, although conventional fluorescence titrations are consistent with 1:1 binding model, alternative forms of analysis â Job plot and an NMR titration â at higher concentrations do provide evidence for 1:2 HâąG 2 complex formation. The observation of guests binding in pairs in some cases opens up new possibilities for altered reactivity of bound guests, and also highlights the recentlyâarticulated difficulties associated with determining stoichiometry of supramolecular complexes in solution
Design for Behaviour Change as a Driver for Sustainable Innovation: Challenges and Opportunities for Implementation in the Private and Public Sectors
Over the last decade, design for behaviour change has become increasingly recognised as a strategy for enabling social change. Despite this, we are far from understanding its implementation, especially through the private and public sectors. This study has surveyed private and public sector stakeholders with regard to their current knowledge of, and approach to, design for behaviour change. The aim was to identify the challenges for professional stakeholders in understanding, accessing and implementing design for behaviour change. Underpinned by a literature review of design for behaviour change theories and approaches, an online survey and two focus groups with private and public sector stakeholders were conducted with particular focus on small and medium size enterprises (SMEs). The results identified that there is a significant disconnect between available theoretical knowledge of design for behaviour change and its practical implementation. Reasons for this include a lack of awareness and common language, of evidence based examples, and of evaluation methods and inter-sector collaborations. In response, a set of recommendations has been developed to propose ways forward for the wider understanding and application of design for behaviour change
The use of a physiologically based pharmacokinetic model to evaluate deconvolution measurements of systemic absorption
BACKGROUND: An unknown input function can be determined by deconvolution using the systemic bolus input function (r) determined using an experimental input of duration ranging from a few seconds to many minutes. The quantitative relation between the duration of the input and the accuracy of r is unknown. Although a large number of deconvolution procedures have been described, these routines are not available in a convenient software package. METHODS: Four deconvolution methods are implemented in a new, user-friendly software program (PKQuest, ). Three of these methods are characterized by input parameters that are adjusted by the user to provide the "best" fit. A new approach is used to determine these parameters, based on the assumption that the input can be approximated by a gamma distribution. Deconvolution methodologies are evaluated using data generated from a physiologically based pharmacokinetic model (PBPK). RESULTS AND CONCLUSIONS: The 11-compartment PBPK model is accurately described by either a 2 or 3-exponential function, depending on whether or not there is significant tissue binding. For an accurate estimate of r the first venous sample should be at or before the end of the constant infusion and a long (10 minute) constant infusion is preferable to a bolus injection. For noisy data, a gamma distribution deconvolution provides the best result if the input has the form of a gamma distribution. For other input functions, good results are obtained using deconvolution methods based on modeling the input with either a B-spline or uniform dense set of time points
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