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Polaritons are light-matter quasiparticles that govern the optical response of quantum materials at the nanoscale, enabling on-chip communication and local sensing. Here, we report Landau-phonon polaritons (LPPs) in magnetized charge-neutral graphene encapsulated in hexagonal boron nitride (hBN). These quasiparticles emerge from the interaction of Dirac magnetoexciton modes in graphene with the hyperbolic phonon polariton modes in hBN. Using infrared magneto-nanoscopy, we reveal the ability to completely halt the LPP propagation in real space at quantized magnetic fields, defying the conventional optical selection rules. The LPP-based nanoscopy also tells apart two fundamental many-body phenomena: the Fermi velocity renormalization and field-dependent magnetoexciton binding energies. Our results highlight the potential of magnetically tuned Dirac heterostructures for precise nanoscale control and sensing of light-matter interaction.

Polaritons, i.e., hybrid quasi-particles of light and matter resonances, have been extensively investigated due to their potential to enhance light-matter interactions. Although polaritonic applications thrive in the mid-infrared range, their extension to the terahertz (THz) range remains limited. Here, we present paratellurite (α-TeO2) nanowires, a versatile material acting as a platform for different types of phonon polaritons. Utilizing synchrotron infrared nanospectroscopy from 10 to 24 THz, we uncover the polaritonic properties of α-TeO2 nanowires, showcasing their dual functionality as both a Fabry-Pérot cavity and a waveguide for surface phonon polaritons. Furthermore, near-field measurements with a free-electron laser as a THz source reveal a localized optical contrast down to 5.5 THz, an indication of hyperbolic bands. Our findings complement the repertoire of polaritonic materials, with significant implications for advancing THz technologies.

IntroductionThe Swiss allocation system for kidney transplantation has evolved over time to balance medical urgency, immunological compatibility, and waiting time. Since the introduction of the transplantation law in 2007, which imposed organ allocation on a national level, the algorithm has been optimized. Initially based on waiting time, HLA compatibility, and crossmatch performed by cell complement-dependent cytotoxicity techniques, the system moved in 2012 to a score including HLA compatibility, waiting time, anti-HLA antibodies detected by the Luminex® technology, and a virtual crossmatch. In 2015, the score was optimized to balance the impact of preemptive listing and HLA matching of hyperimmunized recipients.MethodsWe reviewed access to transplants and post-transplant outcomes along those changes, defining three periods (v0: 2007–2012, v1: 2012–2015, v2: 2015–2020).ResultsChanges in the Swiss allocation system improved the fairness of access to transplantation, particularly for hyperimmunized patients. However, the system still fails to grant fair access to some blood groups. Furthermore, our data showed that rule modifications did not impact early post-transplant complications, maintaining similar time to first rejection and 1-year graft survival across subgroups.DiscussionSuch an analysis is useful for validating changes made to the allocation system and identifying aspects that need to be implemented in future revisions.

Magnetic fields can have profound effects on the motion of electrons in quantum materials. Two-dimensional electron systems subject to strong magnetic fields are expected to exhibit quantized Hall conductivity, chiral edge currents and distinctive collective modes referred to as magnetoplasmons and magnetoexcitons. Generating these propagating collective modes in charge-neutral samples and imaging them at their native nanometre length scales have thus far been experimentally elusive. Here we visualize propagating magnetoexciton polaritons at their native length scales and report their magnetic-field-tunable dispersion in near-charge-neutral graphene. Imaging these collective modes and their associated nano-electro-optical responses allows us to identify polariton-modulated optical and photo-thermal electric effects at the sample edges, which are the most pronounced near charge neutrality. Our work is enabled by innovations in cryogenic near-field optical microscopy techniques that allow for the nano-imaging of the near-field responses of two-dimensional materials under magnetic fields up to 7 T. This nano-magneto-optics approach allows us to explore and manipulate magnetopolaritons in specimens with low carrier doping via harnessing high magnetic fields.

Background. Since 1998, the Swiss Organ Living-Donor Health Registry (SOL-DHR) has recorded peri- and postoperative complications of living kidney (LK) donors, as reported by all Swiss transplant centers and has collected follow-up data prospectively. Methods. We analyzed the early complications of 2379 consecutive individuals who donated a kidney between January 1998 and June 2022 and assessed their health-related quality of life (HRQoL) 1 y after donation. Results. In total, 447 early complications in 404/2379 LK donors (17.0%) were reported to the SOL-DHR. The frequency of donors with major complications (ie, Dindo-Clavien classification 3/4) was 2.4%. In total, 31 donors needed reoperation, and in 13/31 (42%), donors reoperation was necessary because of bleeding complications. Independent risk factors for major early complications were older donor age (P = 0.005) and type of surgical approach (ie, the laparoscopic retroperitoneal compared with laparoscopic transabdominal surgery; P = 0.01), but not sex. We observed a U-shaped association of body mass index, where very low/high body mass indexes had higher odds of major early complications, without reaching statistical significance. Although HRQoL was affected by kidney donation, 96.5% of donors indicated that they would donate their kidney again. The only independent risk factor for low HRQoL based on mental health scores was worsening EB after living kidney donation (P

Infrared nano-spectroscopy based on scattering-type scanning near-field optical microscopy (s-SNOM) is commonly employed to probe the vibrational fingerprints of materials at the nanometer length scale. However, due to the elongated and axisymmetric tip shank, s-SNOM is less sensitive to the in-plane sample anisotropy in general. In this article, we report an easy-to-implement method to probe the in-plane dielectric responses of materials with the assistance of a metallic disk micro-antenna. As a proof-of-concept demonstration, we investigate here the in-plane phonon responses of two prototypical samples, i.e. in (100) sapphire and x-cut lithium niobate (LiNbO3). In particular, the sapphire in-plane vibrations between 350 cm-1 to 800 cm-1 that correspond to LO phonon modes along the crystal b- and c-axis are determined with a spatial resolution of

BackgroundLiving donor (LD) kidney transplantation in the setting of ABO blood group incompatibility (ABOi) has been previously reported to be associated with increased risk for antibody-mediated rejection (ABMR). It is however unclear if the presence of pre-transplant donor specific antibodies (DSA) works as an additive risk factor in the setting of ABOi and if DSA positive ABOi transplants have a significantly worse long-term outcome as compared with ABO compatible (ABOc) DSA positive transplants.MethodsWe investigated the effect of pre-transplant DSA in the ABOi and ABOc setting on the risk of antibody-mediated rejection (ABMR) and graft loss in a cohort of 952 LD kidney transplants.ResultsWe found a higher incidence of ABMR in ABOi transplants as compared to ABOc transplants but this did not significantly affect graft survival or overall survival which was similar in both groups. The presence of pre-transplant DSA was associated with a significantly increased risk of ABMR and graft loss both in the ABOi and ABOc setting. We could not detect an additional risk of DSA in the ABOi setting and outcomes were comparable between DSA positive ABOi and ABOc recipients. Furthermore, a combination of DSA directed at both Class I and Class II, as well as DSA with a high mean fluorescence intensity (MFI) showed the strongest relation to ABMR development and graft loss.ConclusionThe presence of pre-transplant DSA was associated with a significantly worse long-term outcome in both ABOi and ABOc LD kidney transplants and our results suggests that the risk associated with pre-transplant DSA is perhaps not augmented in the ABOi setting. Our study is the first to investigate the long-term effects of DSA in the ABOi setting and argues that pre-transplant DSA risk could potentially be evaluated similarly regardless of ABO compatibility status.

BackgroundEnterobacterales are often responsible for urinary tract infection (UTI) in kidney transplant recipients. Among these, Escherichia coli or Klebsiella species producing extended-spectrum beta-lactamase (ESBL) are emerging. However, there are only scarce data on frequency and impact of ESBL-UTI on transplant outcomes.MethodsWe investigated frequency and impact of first-year UTI events with ESBL Escherichia coli and/or Klebsiella species in a prospective multicenter cohort consisting of 1,482 kidney transplants performed between 2012 and 2017, focusing only on 389 kidney transplants having at least one UTI with Escherichia coli and/or Klebsiella species. The cohort had a median follow-up of four years.ResultsIn total, 139/825 (17%) first-year UTI events in 69/389 (18%) transplant recipients were caused by ESBL-producing strains. Both UTI phenotypes and proportion among all UTI events over time were not different compared with UTI caused by non-ESBL-producing strains. However, hospitalizations in UTI with ESBL-producing strains were more often observed (39% versus 26%, p = 0.04). Transplant recipients with first-year UTI events with an ESBL-producing strain had more frequently recurrent UTI (33% versus 18%, p = 0.02) but there was no significant difference in one-year kidney function as well as longer-term graft and patient survival between patients with and without ESBL-UTI.ConclusionFirst-year UTI events with ESBL-producing Escherichia coli and/or Klebsiella species are associated with a higher need for hospitalization but do neither impact allograft function nor allograft and patient survival.

Hyperbolic phonon polaritons have recently attracted considerable attention in nanophotonics mostly due to their intrinsic strong electromagnetic field confinement, ultraslow polariton group velocities, and long lifetimes. Here we introduce tin oxide (SnO2) nanobelts as a photonic platform for the transport of surface and volume phonon polaritons in the mid- to far-infrared frequency range. This report brings a comprehensive description of the polaritonic properties of SnO2 as a nanometer-sized dielectric and also as an engineered material in the form of a waveguide. By combining accelerator-based IR-THz sources (synchrotron and free-electron laser) with s-SNOM, we employed nanoscale far-infrared hyper-spectral-imaging to uncover a Fabry-Perot cavity mechanism in SnO2 nanobelts via direct detection of phonon-polariton standing waves. Our experimental findings are accurately supported by notable convergence between theory and numerical simulations. Thus, the SnO2 is confirmed as a natural hyperbolic material with unique photonic properties essential for future applications involving subdiffractional light traffic and detection in the far-infrared range.

Using a comparative approach is a widespread method in educational research. Previous cross-cultural comparison studies on teachers' attitudes towards inclusive education show a strong lack of focus on preschool teachers' attitudes towards inclusion. Thus, this study examined 65 Chinese and 59 German preschool teachers' attitudes towards inclusion by applying the Multidimensional Attitudes towards Preschool Inclusive Education Scale (MATPIES). A comparative analysis showed Chinese and German teachers' overall attitudes towards inclusive education as positive, with German teachers' attitudes being more positive. While teachers in both countries showed the highest behavioural attitude dimension scores, Chinese teachers' affective attitude dimension scored the lowest. Guided by the 'cultural-historical framework', we discussed how individualistic and collectivistic values influence teachers' overall attitudes in the two countries, especially their different scores in affective dimension of attitude. Implications for future research examining preschool teachers' attitudes in China and Germany as well as in the international context are discussed, with an emphasis on exploring how various factors both within and beyond teacher attributes to generate a more comprehensive understanding of the critical issue of teachers' attitude. Meanwhile, further indications for conducting international comparison studies on teachers' attitudes are also presented, including some methodological considerations for such studies.

Background Chronic health conditions, secondary conditions, and decreasing functional ability related to aging and/or changes in underlying impairment may influence participation for persons aging with long-term physical disability (AwD). Objective To examine sample integrity and baseline findings through exploration of associations of sociodemographic, health, and disability factors with social participation for persons AwD. Methods This is a longitudinal cohort study following persons AwD over three years, reporting baseline cohort study data. A convenience sample of 474 persons AwD aged 45–65 reporting physical disability of ≥5 years’ duration was recruited through community organizations and social media. The cohort was majority female (66.7%) and single (62.0%), and over one-third (38.6%) was non-White. Pain, fatigue, depression, ability to participate in, and satisfaction with, social roles and activities were measured with the Patient Reported Outcomes Measurement Information System. Results were manually compared against AwD study samples identified through a focused literature review and national census data. Results Participants aged 55–60 and 61–65 had significantly lower rates of employment and marriage and higher rates of living alone than participants aged 45–54. Participants reported higher rates of fatigue, pain, and depression and lower ability to participate in, and satisfaction with, participation in, social roles and activities than the general population. Ability to participate and satisfaction with participation were highest among Black/African American participants. Conclusions Participants reported higher rates of common AwD symptoms and lower ability to participate and satisfaction with participation than the general population, consistent with prior studies of AwD samples. This cohort reflects the AwD population and can be considered an AwD sample, comparable to those found in existing literature. The focus of future analyses will be to gain a greater understanding of chronic health conditions, incidence of falls, engagement in everyday life activities, and the impact of the environment.

While fictional orality (spoken language in fictional texts) has received some attention in the context of quantitative register studies at the interface of linguistics and literature, only a few attempts have been made so far to apply the quantitative methods of register studies to interior monologues (and other forms of inner speech or thought representation). This article presents a case study of the three main characters of James Joyce’s Ulysses whose thoughts are presented extensively in the novel, i.e., Leopold and Molly Bloom and Stephen Dedalus. Making use of quantitative, corpus-based methods, the thoughts of these characters are compared to fictional direct speech and (literary and non-literary) reference texts. We show that the interior monologues of Ulysses span a range of non-narrative registers with varying degrees of informational density and involvement. The thoughts of one character, Leopold Bloom, differ substantially from that character’s speech. The relative heterogeneity across characters is taken as an indication that interior monologue is used as a means of perspective taking and implicit characterization.

Background Chronic health conditions, secondary conditions, and decreasing functional ability related to aging and/or changes in underlying impairment may influence participation for persons aging with long-term physical disability (AwD). Objective To examine sample integrity and baseline findings through exploration of associations of sociodemographic, health, and disability factors with social participation for persons AwD. Methods This is a longitudinal cohort study following persons AwD over three years, reporting baseline cohort study data. A convenience sample of 474 persons AwD aged 45–65 reporting physical disability of ≥5 years’ duration was recruited through community organizations and social media. The cohort was majority female (66.7%) and single (62.0%), and over one-third (38.6%) was non-White. Pain, fatigue, depression, ability to participate in, and satisfaction with, social roles and activities were measured with the Patient Reported Outcomes Measurement Information System. Results were manually compared against AwD study samples identified through a focused literature review and national census data. Results Participants aged 55–60 and 61–65 had significantly lower rates of employment and marriage and higher rates of living alone than participants aged 45–54. Participants reported higher rates of fatigue, pain, and depression and lower ability to participate in, and satisfaction with, participation in, social roles and activities than the general population. Ability to participate and satisfaction with participation were highest among Black/African American participants. Conclusions Participants reported higher rates of common AwD symptoms and lower ability to participate and satisfaction with participation than the general population, consistent with prior studies of AwD samples. This cohort reflects the AwD population and can be considered an AwD sample, comparable to those found in existing literature. The focus of future analyses will be to gain a greater understanding of chronic health conditions, incidence of falls, engagement in everyday life activities, and the impact of the environment.

ABSTRACT Calcium (Ca2+) is an important second messenger for activating stress response signaling and cell adaptation in eukaryotic cells yet intracellular Ca2+-dynamics in fungi are poorly understood due to lack of effective real-time Ca2+ reporters. We engineered the GCaMP6f construct for use in the fungal pathogen, Candida albicans, and used live-cell imaging to observe both dynamic Ca2+ spiking and slower changes in non-spiking Ca2+-GCaMP signals elicited by stress or gene deletion. Short-term exposure to membrane, osmotic or oxidative stress generated immediate stress-specific responses and repeated exposure revealed differential recovery signatures. Osmotic stress caused yeast cell shrinkage and no adaptation response, where Ca2+-GCaMP spiking was inhibited by 1 M NaCl but not by 0.666 M CaCl2. Treatment with sodium dodecylsulfate (SDS) caused a spike-burst, raised the non-spiking Ca2+-GCaMP signals, and caused significant cell death, but surviving cells adapted over subsequent exposures. Treatment with 5 mM H2O2 abolished spiking and caused transient non-GCaMP-related autofluorescence, but cells adapted such that spiking returned and autofluorescence diminished on repeated exposure. Adaptation to H2O2 was dependent on Cap1, extracellular Ca2+, and calcineurin but not on its downstream target, Crz1. Ca2+-dynamics were not affected by H2O2 in the hog1Δ or yvc1Δ mutants, suggesting a pre-adapted, resistant state, possibly due to changes in membrane permeability. Live-cell imaging of Ca2+-GCaMP responses in individual cells has, therefore, revealed the dynamics of Ca2+-influx, signaling and homeostasis, and their role in the temporal stress response signatures of C. albicans. IMPORTANCE Intracellular calcium signaling plays an important role in the resistance and adaptation to stresses encountered by fungal pathogens within the host. This study reports the optimization of the GCaMP fluorescent calcium reporter for live-cell imaging of dynamic calcium responses in single cells of the pathogen, Candida albicans, for the first time. Exposure to membrane, osmotic or oxidative stress generated both specific changes in single cell intracellular calcium spiking and longer calcium transients across the population. Repeated treatments showed that calcium dynamics become unaffected by some stresses but not others, consistent with known cell adaptation mechanisms. By expressing GCaMP in mutant strains and tracking the viability of individual cells over time, the relative contributions of key signaling pathways to calcium flux, stress adaptation, and cell death were demonstrated. This reporter, therefore, permits the study of calcium dynamics, homeostasis, and signaling in C. albicans at a previously unattainable level of detail.

Multiferroic BiFeO3 (BFO) shows several phonon modes at infrared (IR) to THz energies, which are expected to carry information on any sample property coupled to crystal lattice vibrations. While macroscopic IR studies of BFO are often limited by single-crystal size, scattering-type scanning near-field optical microscopy (s-SNOM) allows for IR thin film spectroscopy of nanoscopic probing volumes with negligible direct substrate contribution to the optical signal. In fact, polaritons such as phonon polaritons of BFO introduce a resonant tip-sample coupling in s-SNOM, leading to both stronger signals and enhanced sensitivity to local material properties. Here, we explore the near-field response of BFO thin films at three consecutive resonances (centered around 5 THz, 13 THz, and 16 THz), by combining s-SNOM with a free-electron laser. We study the dependence of these near-field resonances on both the wavelength and tip-sample distance. Enabled by the broad spectral range of the measurement, we probe phonon modes connected to the predominant motion of either the bismuth or oxygen ions. Therefore, we propose s-SNOM at multiple near-field resonances as a versatile and very sensitive tool for the simultaneous investigation of various sample properties.

BACKGROUND: Addressing the current demographic development, the efficacy and safety of kidney transplantations from very senior donors needs to be carefully evaluated. The aim of this study was to analyse patient and graft outcomes of kidney allograft recipients stratified by donor age. METHODS: We retrospectively investigated n = 491 patients from a prospective, observational renal transplant cohort. Patients with kidneys from very old donors (n = 75, aged >70 years), elderly donors (n = 158, between 60–70 years), and regular donors (n = 258, aged