P33. Design and evaluation of an Escherichia coli biomarker for indication of pH

Measuring pH is one of the most commonly used techniques in both the laboratory as well as the field due to its importance in a multitude of biochemical processes. Traditional methods of measuring pH may be highly developed in accuracy and precision but often involve disruption of the environment. Biological markers offer an alternative that allows for long-term pH monitoring. This innovative approach allows for vast applications such as in the manufacturing, food processing and research industries. Under moderate acidic conditions, the asr (acid shock RNA) gene is highly inducible and has been demonstrated to be crucial for growth at high acidities. The alx locus in E. coli contains a putative transporter preceded by a pH-induced riboregulator that operates under moderately alkaline conditions. In this study, vivid blue/purple and green/blue chromoproteins, cJBlue and amilCP respectively, were used as visual indicators. DH5α competent E. coli cells were transformed with recombinant plasmids containing either amilCP downstream the asr promoter or cjBlue downstream the alx promoter and 5’UTR, giving rise to the alx-cjBlue and asr-amilCP cell lines. Through this methodology, we were able to create strains of E. coli that expressed either a blue or blue-green chromoprotein under low or high pHs respectively

Promoting Business Schools: A Content Analysis of Business Schools Magazines

Among the efforts made to attract students and supporters, many business schools use brochures or magazines to build and maintain relationships with alumni and other stakeholders, to attract new students, and to improve their overall visibility. These promotional materials have various contents, such as message from the dean, academic programs, student achievements, or faculty and staff news, among others. We perform a content analysis on the extent to which the content is utilized by AACSB-accredited business schools in the United States. The study provides an initial picture of self-promotion of business schools using school magazines. The result will increase our knowledge in the area of higher education marketing and help inform marketing professionals in business schools and colleges or universities in general

A Differentially Private Weighted Empirical Risk Minimization Procedure and its Application to Outcome Weighted Learning

It is commonplace to use data containing personal information to build predictive models in the framework of empirical risk minimization (ERM). While these models can be highly accurate in prediction, results obtained from these models with the use of sensitive data may be susceptible to privacy attacks. Differential privacy (DP) is an appealing framework for addressing such data privacy issues by providing mathematically provable bounds on the privacy loss incurred when releasing information from sensitive data. Previous work has primarily concentrated on applying DP to unweighted ERM. We consider an important generalization to weighted ERM (wERM). In wERM, each individual's contribution to the objective function can be assigned varying weights. In this context, we propose the first differentially private wERM algorithm, backed by a rigorous theoretical proof of its DP guarantees under mild regularity conditions. Extending the existing DP-ERM procedures to wERM paves a path to deriving privacy-preserving learning methods for individualized treatment rules, including the popular outcome weighted learning (OWL). We evaluate the performance of the DP-wERM application to OWL in a simulation study and in a real clinical trial of melatonin for sleep health. All empirical results demonstrate the viability of training OWL models via wERM with DP guarantees while maintaining sufficiently useful model performance. Therefore, we recommend practitioners consider implementing the proposed privacy-preserving OWL procedure in real-world scenarios involving sensitive data.Comment: 24 pages and 2 figures for the main manuscript, 5 pages and 2 figures for the supplementary material

High-energy mid-infrared sub-cycle pulse synthesis from a parametric amplifier

High-energy phase-stable sub-cycle mid-infrared pulses can provide unique opportunities to explore phase-sensitive strong-field light-matter interactions in atoms, molecules and solids. At the mid-infrared wavelength, the Keldysh parameter could be much smaller than unity even at relatively modest laser intensities, enabling the study of the strong-field sub-cycle electron dynamics in solids without damage. Here we report a high-energy sub-cycle pulse synthesiser based on a mid-infrared optical parametric amplifier and its application to high-harmonic generation in solids. The signal and idler combined spectrum spans from 2.5 to 9.0 μm. We coherently synthesise the passively carrier-envelope phase-stable signal and idler pulses to generate 33 μJ, 0.88-cycle, multi-gigawatt pulses centred at ~4.2 μm, which is further energy scalable. The mid-infrared sub-cycle pulse is used for driving high-harmonic generation in thin silicon samples, producing harmonics up to ~19th order with a continuous spectral coverage due to the isolated emission by the sub-cycle driver

Experimental demonstration of superresolution of partially coherent light sources using parity sorting

Analyses based on quantum metrology have shown that the ability to localize the positions of two incoherent point sources can be significantly enhanced through the use of mode sorting. Here we theoretically and experimentally investigate the effect of partial coherence on the sub-diffraction limit localization of two sources based on parity sorting. With the prior information of a negative and real-valued degree of coherence, higher Fisher information is obtained than that for the incoherent case. Our results pave the way to clarifying the role of coherence in quantum limited metrology

Effect of Layer-Stacking on the Electronic Structure of Graphene Nanoribbons

The evolution of electronic structure of graphene nanoribbons (GNRs) as a function of the number of layers stacked together is investigated using \textit{ab initio} density functional theory (DFT) including interlayer van der Waals interactions. Multilayer armchair GNRs (AGNRs), similar to single-layer AGNRs, exhibit three classes of band gaps depending on their width. In zigzag GNRs (ZGNRs), the geometry relaxation resulting from interlayer interactions plays a crucial role in determining the magnetic polarization and the band structure. The antiferromagnetic (AF) interlayer coupling is more stable compared to the ferromagnetic (FM) interlayer coupling. ZGNRs with the AF in-layer and AF interlayer coupling have a finite band gap while ZGNRs with the FM in-layer and AF interlayer coupling do not have a band gap. The ground state of the bi-layer ZGNR is non-magnetic with a small but finite band gap. The magnetic ordering is less stable in multilayer ZGNRs compared to single-layer ZGNRs. The quasipartcle GW corrections are smaller for bilayer GNRs compared to single-layer GNRs because of the reduced Coulomb effects in bilayer GNRs compared to single-layer GNRs.Comment: 10 pages, 5 figure

Normal Hematopoietic Stem Cell Function in Mice with Enforced Expression of the Hippo Signaling Effector YAP1

The Hippo pathway has recently been implicated in the regulation of organ size and stem cells in multiple tissues. The transcriptional cofactor yes-associated protein 1 (Yap1) is the most downstream effector of Hippo signaling and is functionally repressed by the upstream components of the pathway. Overexpression of YAP1 stimulates proliferation of stem and progenitor cells in many tissues, consistent with inhibition of Hippo signaling. To study the role of Hippo signaling in hematopoietic stem cells (HSCs), we created a transgenic model with inducible YAP1 expression exclusively within the hematopoietic system. Following 3 months induction, examination of blood and bone marrow in the induced mice revealed no changes in the distribution of the hematopoietic lineages compared to control mice. Moreover, the progenitor cell compartment was unaltered as determined by colony forming assays and immunophenotyping. To address whether YAP1 affects the quantity and function of HSCs we performed competitive transplantation experiments. We show that ectopic YAP1 expression does not influence HSC function neither during steady state nor in situations of hematopoietic stress. This is in sharp contrast to effects seen on stem- and progenitor cells in other organs and suggests highly tissue specific functions of the Hippo pathway in regulation of stem cells

Two Intermediate-mass Transiting Brown Dwarfs from the TESS Mission

We report the discovery of two intermediate-mass transiting brown dwarfs (BDs), TOI-569b and TOI-1406b, from NASA's Transiting Exoplanet Survey Satellite mission. TOI-569b has an orbital period of P = 6.55604 +- 0.00016 days, a mass of M b = 64.1 +- 1.9 ${M}_{{\rm{J}}}$, and a radius of R b = 0.75 +- 0.02 ${R}_{{\rm{J}}}$. Its host star, TOI-569, has a mass of M sstarf = 1.21 +- 0.05 $\,{M}_{\odot }$, a radius of R sstarf = 1.47 +- 0.03 $\,{R}_{\odot }$, $[\mathrm{Fe}/{\rm{H}}]=+0.29\pm 0.09$ dex, and an effective temperature of T eff = 5768 +- 110 K. TOI-1406b has an orbital period of P = 10.57415 +- 0.00063 days, a mass of M b = 46.0 +- 2.7 ${M}_{{\rm{J}}}$, and a radius of R b = 0.86 +- 0.03 ${R}_{{\rm{J}}}$. The host star for this BD has a mass of M sstarf = 1.18 +- 0.09 $\,{M}_{\odot }$, a radius of R sstarf = 1.35 +- 0.03 $\,{R}_{\odot }$, $[\mathrm{Fe}/{\rm{H}}]=-0.08\pm 0.09$ dex, and an effective temperature of T eff = 6290 +- 100 K. Both BDs are in circular orbits around their host stars and are older than 3 Gyr based on stellar isochrone models of the stars. TOI-569 is one of two slightly evolved stars known to host a transiting BD (the other being KOI-415). TOI-1406b is one of three known transiting BDs to occupy the mass range of 40-50 ${M}_{{\rm{J}}}$ and one of two to have a circular orbit at a period near 10 days (with the first being KOI-205b). Both BDs have reliable ages from stellar isochrones, in addition to their well-constrained masses and radii, making them particularly valuable as tests for substellar isochrones in the BD mass-radius diagram.Funding for this work was provided by the National Science Foundation Graduate Research Fellowship Program Fellowship (GRFP). This work makes use of observations from the LCOGT network. A.J.M. acknowledges support from the Knut & Alice Wallenberg Foundation (project grant 2014.0017) and the Walter Gyllenberg Foundation of the Royal Physiographical Society in Lund. C.M.P. and M.F. gratefully acknowledge the support of the Swedish National Space Agency (DNR 163/16). A.J. and R.B. acknowledge support by the Ministry for the Economy, Development, and Tourism’s Programa Iniciativa Científica Milenio through grant IC 120009, awarded to the Millennium Institute of Astrophysics (MAS). A.J. acknowledges additional support from FONDECYT project 1171208

Differential information in large games with strategic complementarities

We study equilibrium in large games of strategic complementarities (GSC) with differential information. We define an appropriate notion of distributional Bayesian Nash equilibrium and prove its existence. Furthermore, we characterize order-theoretic properties of the equilibrium set, provide monotone comparative statics for ordered perturbations of the space of games, and provide explicit algorithms for computing extremal equilibria. We complement the paper with new results on the existence of Bayesian Nash equilibrium in the sense of Balder and Rustichini (J Econ Theory 62(2):385–393, 1994) or Kim and Yannelis (J Econ Theory 77(2):330–353, 1997) for large GSC and provide an analogous characterization of the equilibrium set as in the case of distributional Bayesian Nash equilibrium. Finally, we apply our results to riot games, beauty contests, and common value auctions. In all cases, standard existence and comparative statics tools in the theory of supermodular games for finite numbers of agents do not apply in general, and new constructions are required

Architectures for Multinode Superconducting Quantum Computers

Many proposals to scale quantum technology rely on modular or distributed designs where individual quantum processors, called nodes, are linked together to form one large multinode quantum computer (MNQC). One scalable method to construct an MNQC is using superconducting quantum systems with optical interconnects. However, a limiting factor of these machines will be internode gates, which may be two to three orders of magnitude noisier and slower than local operations. Surmounting the limitations of internode gates will require a range of techniques, including improvements in entanglement generation, the use of entanglement distillation, and optimized software and compilers, and it remains unclear how improvements to these components interact to affect overall system performance, what performance from each is required, or even how to quantify the performance of each. In this paper, we employ a `co-design' inspired approach to quantify overall MNQC performance in terms of hardware models of internode links, entanglement distillation, and local architecture. In the case of superconducting MNQCs with microwave-to-optical links, we uncover a tradeoff between entanglement generation and distillation that threatens to degrade performance. We show how to navigate this tradeoff, lay out how compilers should optimize between local and internode gates, and discuss when noisy quantum links have an advantage over purely classical links. Using these results, we introduce a roadmap for the realization of early MNQCs which illustrates potential improvements to the hardware and software of MNQCs and outlines criteria for evaluating the landscape, from progress in entanglement generation and quantum memory to dedicated algorithms such as distributed quantum phase estimation. While we focus on superconducting devices with optical interconnects, our approach is general across MNQC implementations.Comment: 23 pages, white pape