Effective Three-Body Interactions in Jaynes-Cummings-Hubbard Systems

A generalisation of the Jaynes-Cummings-Hubbard model for coupled-cavity arrays is introduced, where the embedded two-level system in each cavity is replaced by a $\Xi$-type three-level system. We demonstrate that the resulting effective polariton-polariton interactions at each site are both two-body and three-body. By tuning the ratio of the two transition dipole matrix elements, we show that the strength and sign of the two-body interaction can be controlled whilst maintaining a three-body repulsion. We then proceed to demonstrate how different two-body and three-body interactions alter the mean field superfluid-Mott insulator phase diagram, with the possible emergence of a pair superfluid phase in the two-body attractive regime.Comment: 10 pages, 4 figures, accepted for publication in Scientific Reports; v3 - revised manuscrip

Practical security bounds against the Trojan-horse attack in quantum key distribution

In the quantum version of a Trojan-horse attack, photons are injected into the optical modules of a quantum key distribution system in an attempt to read information direct from the encoding devices. To stop the Trojan photons, the use of passive optical components has been suggested. However, to date, there is no quantitative bound that specifies such components in relation to the security of the system. Here, we turn the Trojan-horse attack into an information leakage problem. This allows us quantify the system security and relate it to the specification of the optical elements. The analysis is supported by the experimental characterization, within the operation regime, of reflectivity and transmission of the optical components most relevant to security.Comment: 18 pages, 11 figures. Some typos correcte

Building belonging in online WIL environments – lessons (re)learnt in the pandemic age: a collaborative enquiry

The theme of belonging in e-pedagogy gained currency in the 2000s when educational providers hastened to join the online teaching and learning boom and studies of building and maintaining a sense of community (SOC) proved central to this endeavour. Motivated by the pandemic-era necessity to convene teaching and learning online as part of a response to super-complexity as a defining feature of tertiary education in the 21st century, work-integrated learning (WIL) practitioners returned to this scholarship to consider, under pressure, modes of building SOC and belonging in online spaces. Underpinned by a broadly constructivist worldview and informed by the Community of Inquiry (CoI) framework, our COVID-age study considers what pedagogical strategies are viewed as affording learners this sense of belonging - or not. Using a collaborative enquiry to pool our perceptions and experiences from three WIL contexts, we ask how work-integrated learning (WIL) practitioners build belonging in online spaces and identify strategies learners perceive as valuable. Drawing on the authors’ small-scale studies of educator and learner experiences of online WIL (eWIL), our collaborative enquiry uses qualitative descriptive analysis to identify key themes in the voices of students. Advancing the scholarship, our study identifies three threads to the fabric of belonging: humanising online WIL; the importance of mentor presence; and fostering professional belonging. The study suggests that strategies impacting these three areas are at the heart of building belonging in online spaces, broadly envisaged as imagined professional communities of practice. Techniques viewed as successful are advanced as possibilities for enhancing pedagogy in online WIL communities

Multiparty Electoral Competition in the Netherlands and Germany: A Model Based on Multinomial Probit

A typical assumption of electoral models of party competition is that parties adopt policy positions so as to maximize expected vote share. Here we use Euro-barometer survey data and European elite-study data from 1979 for the Netherlands and Germany to construct a stochastic model of voter response, based on multinomial probit estimation. For each of these countries, we estimate a pure spatial electoral voting model and a joint spatial model. The latter model also includes individual voter and demographic characteristics. The pure spatial models for the two countries quite accurately described the electoral response as a stochastic function of party positions. We use these models to perform a thought experiment so as to estimate the expected vote maximizing party positions. We go on to propose a model of internal party decision-making based both on pre-election electoral estimation and postelection coalition bargaining. This model suggests why the various parties in the period in question did not adopt vote maximizing positions. We argue that maximizing expected vote will not, in general, be a rational party strategy in multiparty political systems which are based on proportional representation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/116246/1/pc98.pd

Impact of GE Crop Adoption on Quality-Adjusted Herbicide Use in U.S. Corn Production

This paper presents findings on the use of HT corn and quality-adjusted herbicide use for 12 key corn producing states using a panel data set for 1986-2008. Our preliminary findings indicate an insignificant impact of HT corn on herbicide use, conditioning or accounting for HT corn with other important drivers of corn herbicide use: HT soy, corn output price, glyphoste price, nonherbicide glyponsate price, and percentage of continuous corn and low-till corn. However, we find a positive and significant impact of HT corn on herbicide use in selected states, using regional interaction terms. We use econometric techniques to avoid spurious regression results. Other preliminary runs indicated that the results hold when running the US and regional interactions on 1986-2006 and 1986-2007 data.HT-corn, herbicides, weed resistance, glyphosate, corn, Environmental Economics and Policy, Farm Management, Production Economics,

A comparison of broad-spectrum and narrow-spectrum dry cow therapy used alone and in combination with a teat sealant

The dry period is a critical time in the lactation cycle, offering the optimum time for cure of existing intramammary infection (IMI), while also encompassing the periods of highest susceptibility to new intramammary infection. Until recent years, intramammary infection in the dry period has been controlled with the use of antibiotic dry cow therapy. The aim of this study was to investigate 3 different dry cow therapy regimens, in low-somatic cell count (SCC; bulk milk SCC < 250,000 cells/mL) herds in southwest England. A total of 489 cows was recruited to the study and randomly allocated to receive either the broad-spectrum antibiotic cefquinome, a combination treatment comprising the narrow-spectrum antibiotic cloxacillin and an internal teat sealant, or the narrow-spectrum antibiotic cloxacillin alone. All quarters were sampled for bacteriology at drying off and again in the week immediately postcalving; 2 quarters were also sampled 2 wk before the estimated calving date to allow an assessment of infection dynamics during the dry period. Quarters were subsequently monitored for clinical mastitis for the first 100 d of lactation. Conventional multilevel (random effects) models were constructed to assess the efficacy of products in preventing IMI. Survival analysis was used to examine factors that influenced the risk of clinical mastitis using conventional Cox proportional hazards models. No differences were identified between the treatment groups in terms of cure of IMI caused by the major pathogens. Quarters in both the combination and cefquinome-treated groups were more likely to be free of a major pathogen or enterobacterial pathogen postcalving. With respect to clinical mastitis, the cefquinome-treated group was less likely to develop clinical mastitis than was the cloxacillin treated group

Pedagogies of belonging in an anxious world: A collaborative autoethnography of four practitioners

The concept of belonging has found prominence in higher education learning environments, as the COVID-19 pandemic continues to have an unprecedented impact on educational provision. In times of disruption, alienation and isolation, the most basic of our psychological and physiological needs have come to be almost universally recognised as critical factors that must be considered and examined. Experiencing belonging is integral to human existence, and knowing where, with whom, and how we belong, is a salient driver for learning and self-actualisation. We recognise there are a number of ways to frame and approach the idea of belonging in the educational experience. We also recognise that there are multiple understandings of what belonging means and therefore how it is enacted within the curricula and the “classroom” in its varying forms - physical, online, digital, work-based. This Editorial takes a critical perspective to our own intellectual standpoint in relation to pedagogies of belonging. As co-editors, we have outlined our respective conceptions and experiences of belonging as a collaborative autoethnography, capturing our individual views of pedagogies of belonging in a collaborative context. Our collaboration has allowed us to situate ourselves both theoretically and practically, as well as ontologically, and advance our understanding of practices that promote student belonging in all its possible forms within the higher education experience. We suggest that the possibilities for belonging offered by interdisciplinary and transdisciplinary approaches are ripe for inquiry, and the place of non-traditional, Indigenous, iterative and emergent methodologies to examine belonging requires further exploration