Non Standard Tau Pair Production in Two Photon Collisions at LEP II and Beyond

We study the sensitivity of LEP II and NLC, via two photon collisions, to the effects of anomalous $\tau \overline{\tau} \gamma$ couplings. We also discuss some CP-odd observables that can be useful to disentangle the contributions from the anomalous couplings. (5 figures included via epsf appended at the end as uuencoded compressed tar postscript file).Comment: 11 pages, UG-FT-37/94 (names of the figures in the TeX file changed to match the ones in the uuencoded postscript file

Poachers and gamekeepers : processes of class-based organizational closure and usurpation in Sri Lanka’s emerging private sector

In a qualitative study based on 25 interviews, we examine highly skilled workers’ accounts of class-based closure in emerging occupational sectors in Sri Lanka. Our findings reveal holes in the entrance criteria firms demanded to secure their elite status. Highlighting how individuals who were excluded at junior levels negotiate entry at mid/senior levels we show how ‘poachers turn into gamekeepers’ illuminating the dialectical relationship between exclusion and inclusionary usurpation. We contextualise organisational closure, highlighting the influence of wider societal effects on the process

Respectable femininity and career agency: exploring paradoxical imperatives

This paper places respectable femininity at the very centre of career enactment. In the accounts of 24 Sri Lankan women, notions of being a ‘respectable’ woman recurred as respondents described how important it was to adhere to the powerful behavioural norms for women in their organizations and society. However while such respectability was vital for women's career progression, it ultimately restricted their agency and conflicted with other requirements for advancement. Based on our empirical findings, we propose that being a respectable woman was experienced as paradox, where at times it was seen as impossible to be both a good woman and a successful careerist. We highlight the implications of our findings for women's careers in South Asia and more widely

Structure and permeability of ion-channels by integrated AFM and waveguide TIRF microscopy.

Membrane ion channels regulate key cellular functions and their activity is dependent on their 3D structure. Atomic force microscopy (AFM) images 3D structure of membrane channels placed on a solid substrate. Solid substrate prevents molecular transport through ion channels thus hindering any direct structure-function relationship analysis. Here we designed a ~70 nm nanopore to suspend a membrane, allowing fluidic access to both sides. We used these nanopores with AFM and total internal reflection fluorescence microscopy (TIRFM) for high resolution imaging and molecular transport measurement. Significantly, membranes over the nanopore were stable for repeated AFM imaging. We studied structure-activity relationship of gap junction hemichannels reconstituted in lipid bilayers. Individual hemichannels in the membrane overlying the nanopore were resolved and transport of hemichannel-permeant LY dye was visualized when the hemichannel was opened by lowering calcium in the medium. This integrated technique will allow direct structure-permeability relationship of many ion channels and receptors

Respectable femininity and career agency: exploring paradoxical imperatives

This paper places respectable femininity at the very centre of career enactment. In the accounts of 24 Sri Lankan women, notions of being a ‘respectable’ woman recurred as respondents described how important it was to adhere to the powerful behavioural norms for women in their organizations and society. However while such respectability was vital for women's career progression, it ultimately restricted their agency and conflicted with other requirements for advancement. Based on our empirical findings, we propose that being a respectable woman was experienced as paradox, where at times it was seen as impossible to be both a good woman and a successful careerist. We highlight the implications of our findings for women's careers in South Asia and more widely

Urban Air Mobility Market Study

The Booz Allen Team explored market size and potential barriers to Urban Air Mobility (UAM) by focusing on three potential markets – Airport Shuttle, Air Taxi, and Air Ambulance. We found that the Airport Shuttle and Air Taxi markets are viable, with a significant total available market value in the U.S. of $500 billion, for a fully unconstrained scenario. In this unconstrained best-case scenario, passengers would have the ability to access and fly a UAM at any time, from any location to any destination, without being hindered by constraints such as weather, infrastructure, or traffic volume. Significant legal and regulatory, weather, certification, public perception, and infrastructure constraints exist, which reduce the market potential for these applications to only about 0.5$2.5 billion, in the near term. However, we determined that these constraints can be addressed through ongoing intra-governmental partnerships, government and industry collaboration, strong industry commitment, and existing legal and regulatory enablers. We found that the Air Ambulance market is not a viable market if served by electric vertical takeoff and landing (eVTOL) vehicles due to technology constraints but may potentially be viable if a hybrid VTOL aircraft are utilized

Adaptive Annealed Importance Sampling with Constant Rate Progress

Annealed Importance Sampling (AIS) synthesizes weighted samples from an intractable distribution given its unnormalized density function. This algorithm relies on a sequence of interpolating distributions bridging the target to an initial tractable distribution such as the well-known geometric mean path of unnormalized distributions which is assumed to be suboptimal in general. In this paper, we prove that the geometric annealing corresponds to the distribution path that minimizes the KL divergence between the current particle distribution and the desired target when the feasible change in the particle distribution is constrained. Following this observation, we derive the constant rate discretization schedule for this annealing sequence, which adjusts the schedule to the difficulty of moving samples between the initial and the target distributions. We further extend our results to $f$-divergences and present the respective dynamics of annealing sequences based on which we propose the Constant Rate AIS (CR-AIS) algorithm and its efficient implementation for $\alpha$-divergences. We empirically show that CR-AIS performs well on multiple benchmark distributions while avoiding the computationally expensive tuning loop in existing Adaptive AIS

Identification of a WNT5A-Responsive Degradation Domain in the Kinesin Superfamily Protein KIF26B.

Noncanonical WNT pathways function independently of the β-catenin transcriptional co-activator to regulate diverse morphogenetic and pathogenic processes. Recent studies showed that noncanonical WNTs, such as WNT5A, can signal the degradation of several downstream effectors, thereby modulating these effectors' cellular activities. The protein domain(s) that mediates the WNT5A-dependent degradation response, however, has not been identified. By coupling protein mutagenesis experiments with a flow cytometry-based degradation reporter assay, we have defined a protein domain in the kinesin superfamily protein KIF26B that is essential for WNT5A-dependent degradation. We found that a human disease-causing KIF26B mutation located at a conserved amino acid within this domain compromises the ability of WNT5A to induce KIF26B degradation. Using pharmacological perturbation, we further uncovered a role of glycogen synthase kinase 3 (GSK3) in WNT5A regulation of KIF26B degradation. Lastly, based on the identification of the WNT5A-responsive domain, we developed a new reporter system that allows for efficient profiling of WNT5A-KIF26B signaling activity in both somatic and stem cells. In conclusion, our study identifies a new protein domain that mediates WNT5A-dependent degradation of KIF26B and provides a new tool for functional characterization of noncanonical WNT5A signaling in cells

Quantum memories based on engineered dissipation

Storing quantum information for long times without disruptions is a major requirement for most quantum information technologies. A very appealing approach is to use self-correcting Hamiltonians, i.e. tailoring local interactions among the qubits such that when the system is weakly coupled to a cold bath the thermalization process takes a long time. Here we propose an alternative but more powerful approach in which the coupling to a bath is engineered, so that dissipation protects the encoded qubit against more general kinds of errors. We show that the method can be implemented locally in four dimensional lattice geometries by means of a toric code, and propose a simple 2D set-up for proof of principle experiments.Comment: 6 +8 pages, 4 figures, Includes minor corrections updated references and aknowledgement