PT symmetry-protected exceptional cones and analogue Hawking radiation

We show that the exceptional surfaces of linear three-dimensional non-Hermitian parity-time-symmetric two-band models attain the form of topologically stable tilted exceptional cones. By relating the exceptional cones to energy cones of two-dimensional Hermitian parity-time-symmetric two-band models, we find a connection between the exceptional cone and the light cone of an observer in the vicinity of a Schwarzschild black hole. When the cone overtilts, light-like particle-antiparticle pairs are created resembling Hawking radiation. We also investigate dissipative features of the non-Hermitian Hamiltonian related to the latter and comment on potential realizations in laboratory setups

Genomic relatedness and diversity of Swedish native cattle breeds

International audienceAbstractBackgroundNative cattle breeds are important genetic resources given their adaptation to the local environment in which they are bred. However, the widespread use of commercial cattle breeds has resulted in a marked reduction in population size of several native cattle breeds worldwide. Therefore, conservation management of native cattle breeds requires urgent attention to avoid their extinction. To this end, we genotyped nine Swedish native cattle breeds with genome-wide 150 K single nucleotide polymorphisms (SNPs) to investigate the level of genetic diversity and relatedness between these breeds.ResultsWe used various SNP-based approaches on this dataset to connect the demographic history with the genetic diversity and population structure of these Swedish cattle breeds. Our results suggest that the Väne and Ringamåla breeds originating from southern Sweden have experienced population isolation and have a low genetic diversity, whereas the Fjäll breed has a large founder population and a relatively high genetic diversity. Based on the shared ancestry and the constructed phylogenetic trees, we identified two major clusters in Swedish native cattle. In the first cluster, which includes Swedish mountain cattle breeds, there was little differentiation among the Fjäll, Fjällnära, Swedish Polled, and Bohus Polled breeds. The second cluster consists of breeds from southern Sweden: Väne, Ringamåla and Swedish Red. Interestingly, we also identified sub-structuring in the Fjällnära breed, which indicates different breeding practices on the farms that maintain this breed.ConclusionsThis study represents the first comprehensive genome-wide analysis of the genetic relatedness and diversity in Swedish native cattle breeds. Our results show that different demographic patterns such as genetic isolation and cross-breeding have shaped the genomic diversity of Swedish native cattle breeds and that the Swedish mountain breeds have retained their authentic distinct gene pool without significant contribution from any of the other European cattle breeds that were included in this study

Human CEACAM1 is targeted by a Streptococcus pyogenes adhesin implicated in puerperal sepsis pathogenesis

Life-threatening bacterial infections in women after childbirth, known as puerperal sepsis, resulted in classical epidemics and remain a global health problem. While outbreaks of puerperal sepsis have been ascribed to Streptococcus pyogenes, little is known about disease mechanisms. Here, we show that the bacterial R28 protein, which is epidemiologically associated with outbreaks of puerperal sepsis, specifically targets the human receptor CEACAM1. This interaction triggers events that would favor development of puerperal sepsis, including adhesion to cervical cells, suppression of epithelial wound repair and subversion of innate immune responses. High-resolution structural analysis showed that an R28 domain with IgI3-like fold binds to the N-terminal domain of CEACAM1. Together, these findings demonstrate that a single adhesin-receptor interaction can drive the pathogenesis of bacterial sepsis and provide molecular insights into the pathogenesis of one of the most important infectious diseases in medical history

Disconnection from nature : Expanding our understanding of human-nature relations

The human relationship with nature is a topic that has been explored throughout human history. More recently, the idea of connection to nature has merged as an important transdisciplinary field of study. Despite increased scholarly attention to connection to nature, the notion of disconnection from nature remains undertheorized and understudied.In this perspective article, we argue for a more comprehensive understanding of disconnection from nature to strengthen theories of human-nature relationships that goes beyond individual relationships and considers social and collective factors of disconnection, including institutional, socio-cultural and power dimensions.Drawing on case insights, we present the 'wheel of disconnection' to illustrate how disconnections from nature manifest across individual or societal meaning-making processes, thereby problematizing existing research that seeks to create dualisms between human positive and negative impacts on the environment in isolation from cultural or political contexts.We do not seek to discount research or important practical efforts to foster an individual's connection to nature by elevating disconnection. Instead, we hope that creating greater awareness and understanding of disconnection will be able to guide opportunities going forward for strengthening a connection to nature along a continuum from the individual to the social. Read the free Plain Language Summary for this article on the Journal blog.Peer reviewe

Health-care costs of losartan and candesartan in the primary treatment of hypertension

A recent study of two widely used angiotensin receptor blockers reported a reduced risk of cardiovascular events (−14.4%) when using candesartan compared with losartan in the primary treatment of hypertension. In addition to clinical benefits, costs associated with treatment strategies must be considered when allocating scarce health-care resources. The aim of this study was to assess resource use and costs of losartan and candesartan in hypertensive patients. Resource use (drugs, outpatient contacts, hospitalizations and laboratory tests) associated with losartan and candesartan treatment was estimated in 14 100 patients in a real-life clinical setting. We electronically extracted patient data from primary care records and mandatory Swedish national registers for death and hospitalization. Patients treated with losartan had more outpatient contacts (+15.6%), laboratory tests (+13.8%) and hospitalizations (+13.8%) compared with the candesartan group. During a maximum observation time of 9 years, the mean total costs per patient were 10 369 Swedish kronor (95% confidence interval: 3109–17 629) higher in the losartan group. In conclusion, prescribing candesartan for the primary treatment of hypertension results in lower long-term health-care costs compared with losartan

The equivalence of numbers: The social value of avoiding health decline: An experimental web-based study

BACKGROUND: Health economic analysis aimed at informing policy makers and supporting resource allocation decisions has to evaluate not only improvements in health but also avoided decline. Little is known however, whether the "direction" in which changes in health are experienced is important for the public in prioritizing among patients. This experimental study investigates the social value people place on avoiding (further) health decline when directly compared to curative treatments in resource allocation decisions. METHODS: 127 individuals completed an interactive survey that was published in the World Wide Web. They were confronted with a standard gamble (SG) and three person trade-off tasks, either comparing improvements in health (PTO-Up), avoided decline (PTO-Down), or both, contrasting health changes of equal magnitude differing in the direction in which they are experienced (PTO-WAD). Finally, a direct priority ranking of various interventions was obtained. RESULTS: Participants strongly prioritized improving patients' health rather than avoiding decline. The mean substitution rate between health improvements and avoided decline (WAD) ranged between 0.47 and 0.64 dependent on the intervention. Weighting PTO values according to the direction in which changes in health are experienced improved their accuracy in predicting a direct prioritization ranking. Health state utilities obtained by the standard gamble method seem not to reflect social values in resource allocation contexts. CONCLUSION: Results suggest that the utility of being cured of a given health state might not be a good approximation for the societal value of avoiding this health state, especially in cases of competition between preventive and curative interventions

Functional Dissection of Streptococcus pyogenes M5 Protein: the Hypervariable Region is Essential for Virulence

The surface-localized M protein of Streptococcus pyogenes is a major virulence factor that inhibits phagocytosis, as determined ex vivo. Because little is known about the role of M protein in vivo we analyzed the contribution of different M protein regions to virulence, using the fibrinogen (Fg)-binding M5 protein and a mouse model of acute invasive infection. This model was suitable, because M5 is required for mouse virulence and binds mouse and human Fg equally well, as shown here. Mixed infection experiments with wild type bacteria demonstrated that mutants lacking the N-terminal hypervariable region (HVR) or the Fg-binding B-repeat region were strongly attenuated, while a mutant lacking the conserved C-repeats was only slightly attenuated. Because the HVR of M5 is not required for phagocytosis resistance, our data imply that this HVR plays a major but unknown role during acute infection. The B-repeat region is required for phagocytosis resistance and specifically binds Fg, suggesting that it promotes virulence by binding Fg. However, B-repeat mutants were attenuated even in Fg-deficient mice, implying that the B-repeats may have a second function, in addition to Fg-binding. These data demonstrate that two distinct M5 regions, including the HVR, are essential to virulence during the early stages of an infection. In particular, our data provide the first in vivo evidence that the HVR of an M protein plays a major role in virulence, focusing interest on the molecular role of this region

Transformative research for sustainability: characteristics, tensions, and moving forward

Technical summary The question of how science can become a lever in achieving the Sustainable Development Goals permeates most recent sustainability research. Wide-ranging literature calling for a transformative approach has emerged in recent years. This 'transformative turn' is fueled by publications from fields such as sustainability science, social-ecological research, conservation science, sustainability transitions, or sustainability governance studies. However, there is a lack of a shared understanding specifically of what is meant for research to be transformative in this developing discourse around doing science differently to tackle sustainability problems. We aim to advance transformative research for sustainability. We define transformative research and outline six of its characteristics: (1) interventional nature and a theory of change focus; (2) collaborative modes of knowledge production, experimentation and learning; (3) systems thinking literacy and contextualization; (4) reflexivity, normative and inner dimensions; (5) local agency, decolonization, and reshaping power; (6) new quality criteria and rethinking impact. We highlight three tensions between transformative research and traditional paradigms of academic research: (1) process- and output-orientation; (2) accountability toward society and toward science; (3) methodologies rooted in scientific traditions and post-normal methodologies. We conclude with future directions on how academia could reconcile these tensions to support and promote transformative research. Non-technical summary Dominant ways of doing research are not enough to achieve the UN Sustainable Development Goals. The typical response of science to dealing with the current local and global sustainability crises is to produce and accumulate more knowledge. Transformative research seeks to couple knowledge production with co-creating change. This paper defines the transformative way of doing research to pro-actively support society's fight against pressing societal and environmental problems. We present six characteristics of transformative research. We reflect on the challenges related to implementing these characteristics in scientific practice and on how academia can play its part

Human CEACAM1 is targeted by a Streptococcus pyogenes adhesin implicated in puerperal sepsis pathogenesis

Life-threatening bacterial infections in women after childbirth, known as puerperal sepsis, resulted in classical epidemics and remain a global health problem. While outbreaks of puerperal sepsis have been ascribed to Streptococcus pyogenes, little is known about disease mechanisms. Here, we show that the bacterial R28 protein, which is epidemiologically associated with outbreaks of puerperal sepsis, specifically targets the human receptor CEACAM1. This interaction triggers events that would favor the development of puerperal sepsis, including adhesion to cervical cells, suppression of epithelial wound repair and subversion of innate immune responses. High-resolution structural analysis showed that an R28 domain with IgI3-like fold binds to the N-terminal domain of CEACAM1. Together, these findings demonstrate that a single adhesin-receptor interaction can drive the pathogenesis of bacterial sepsis and provide molecular insights into the pathogenesis of one of the most important infectious diseases in medical history