Occasional paternal inheritance of the germline-restricted chromosome in songbirds.

Songbirds have one special accessory chromosome, the so-called germline-restricted chromosome (GRC), which is only present in germline cells and absent from all somatic tissues. Earlier work on the zebra finch (Taeniopygia guttata castanotis) showed that the GRC is inherited only through the female line-like the mitochondria-and is eliminated from the sperm during spermatogenesis. Here, we show that the GRC has the potential to be paternally inherited. Confocal microscopy using GRC-specific fluorescent in situ hybridization probes indicated that a considerable fraction of sperm heads (1 to 19%) in zebra finch ejaculates still contained the GRC. In line with these cytogenetic data, sequencing of ejaculates revealed that individual males from two families differed strongly and consistently in the number of GRCs in their ejaculates. Examining a captive-bred male hybrid of the two zebra finch subspecies (T. g. guttata and T. g. castanotis) revealed that the mitochondria originated from a castanotis mother, whereas the GRC came from a guttata father. Moreover, analyzing GRC haplotypes across nine castanotis matrilines, estimated to have diverged for up to 250,000 y, showed surprisingly little variability among GRCs. This suggests that a single GRC haplotype has spread relatively recently across all examined matrilines. A few diagnostic GRC mutations that arose since this inferred spreading suggest that the GRC has continued to jump across matriline boundaries. Our findings raise the possibility that certain GRC haplotypes could selfishly spread through the population via occasional paternal transmission, thereby outcompeting other GRC haplotypes that were limited to strict maternal inheritance, even if this was partly detrimental to organismal fitness.

Cu-Catalyzed Amination of Base-Sensitive Aryl Bromides and the Chemoselective N- and O-Arylation of Amino Alcohols.

We report a general and functional-group-tolerant method for the Cu-catalyzed amination of base-sensitive aryl bromides including substrates possessing acidic functional groups and small five-membered heteroarenes. The results presented herein substantially expand the scope of Cu-catalyzed C-N coupling reactions. The combination of L8, an anionic N1,N2-diarylbenzene-1,2-diamine ligand, along with the mild base NaOTMS leads to the formation of a stable yet reactive catalyst that resists deactivation from coordination to heterocycles or charged intermediates. This system enables the use of low catalyst and ligand loadings. Exploiting the differences in nucleophile deprotonation in C-O and C-N coupling reactions catalyzed by Cu·L8 we developed a method to chemoselectively N- and O-arylate a variety of amino alcohol substrates. Employing NaOt-Bu as the base resulted exclusively in C-O coupling when the amino alcohols featured primary alcohols and more hindered amines or aniline groups. Utilizing NaOTMS enabled the ability to override the steric-based selectivity of these reactions completely and exclusively promoted C-N coupling regardless of the structure of the amino alcohol. The ability to invert the observed chemoselectivity is distinct from previously described methods that require protecting group manipulations or rely entirely on steric effects to control reactivity. These results substantially improve the scope of Cu-catalyzed C-N coupling reactions using N1,N2-diarylbenzene-1,2-diamine ligands and introduce a new chemoselective method to arylate amino alcohols.

Micro Germline-Restricted Chromosome in Blue Tits: Evidence for Meiotic Functions.

The germline-restricted chromosome (GRC) is likely present in all songbird species but differs widely in size and gene content. This extra chromosome has been described as either a microchromosome with only limited basic gene content or a macrochromosome with enriched gene functions related to female gonad and embryo development. Here, we assembled, annotated, and characterized the first micro-GRC in the blue tit (Cyanistes caeruleus) using high-fidelity long-read sequencing data. Although some genes on the blue tit GRC show signals of pseudogenization, others potentially have important functions, either currently or in the past. We highlight the GRC gene paralog BMP15, which is among the highest expressed GRC genes both in blue tits and in zebra finches (Taeniopygia guttata) and is known to play a role in oocyte and follicular maturation in other vertebrates. The GRC genes of the blue tit are further enriched for functions related to the synaptonemal complex. We found a similar functional enrichment when analyzing published data on GRC genes from two nightingale species (Luscinia spp.). We hypothesize that these genes play a role in maintaining standard maternal inheritance or in recombining maternal and paternal GRCs during potential episodes of biparental inheritance.

Adding Patient-Reported Outcomes to the American College of Surgeons National Surgical Quality Improvement Program: Results of the First 33,842 Patients from 65 Hospitals.

OBJECTIVES: To investigate the initial set of patient-reported outcomes (PROs) in the ACS NSQIP and their associations with 30-day surgical outcomes. BACKGROUND: PROs provide important information that can be used to improve routine care and facilitate quality improvement. The ACS conducted a demonstration project to capture PROs into the NSQIP to complement clinical data. METHODS: From 2/2020-3/2023, 65 hospitals collected PROMIS measures assessing global health, pain interference, fatigue, and physical function from patients accrued into the NSQIP. Using multivariable mixed regression, we compared the scores of patients with and without 30-day complications and further analyzed scores exceeding one standard deviation (1-SD) worse than national benchmarks. RESULTS: Overall, 33842 patients completed the PROMIS measures a median 58 days (IQR 47-72) postoperatively. Among patients without complications (n=31210), 33.9% had PRO scores 1-SD worse than national benchmarks. Patients with complications were 1.7-times more likely to report worse PROs (95% CI 1.6-1.8). Patients with complications had lower scores for global physical health (adjusted mean difference [AMD] 2.6, 95% CI 2.2-3.0), lower for global mental health (AMD 1.8, 95% CI 1.4-2.2), higher for pain interference (AMD 2.4, 95% CI 2.0-2.8), higher fatigue (AMD 2.7, 95% CI 2.3-3.1), and lower physical function (AMD 3.2, 95% CI 2.8-3.5). CONCLUSIONS: Postoperative complications negatively affect multiple key dimensions of patients' health-related quality of life. PROs were well below national benchmarks for many patients, even among those without complications. Identifying solutions to improve PROs after surgery thus remains a tremendous quality opportunity.

Tooth Wear Evaluation System 2.0-Evaluation of diagnostic reliability in the assessment of signs and symptoms for tooth wear by non-experts.

BACKGROUND: Tooth wear is a multifactorial condition that manifests through various signs and symptoms. These individual signs and symptoms were described in multiple studies, leading to the inclusion in TWES 2.0 (Tooth Wear Evaluation System 2.0) and the forthcoming DC-TW (Diagnostic Criteria for Tooth Wear). However, a study evaluating their reliability has yet to be conducted. OBJECTIVE: The aim of the study was to examine the reliability in the assessment of 6 signs of pathological tooth wear and 18 clinical signs and symptoms determining aetiology, all of which are included in the TWES 2.0/DC-TW. METHODS: 48 dental students (operators) evaluated patient cases from a patient pool of 14 patients on dental casts and high-resolution intraoral photographs. The agreement between all operators for each sign and symptom was calculated based on ICC (Intraclass Correlation Coefficients). Additionally, the agreement of each operator's evaluation with a predefined sample solution was calculated based on Cohen's kappa. RESULTS: Inter-user agreement ranged from near perfect (0.91) to poor (0.02) for the various pathology signs or aetiology symptoms of tooth wear (mean 0.32). The agreements of the operator's ratings compared to the sample solution resulted in Cohen's kappa from 0.18 to 1 (mean 0.59) for the pathology signs and ranged from 0.02 to 0.51 for the aetiology signs (mean 0.38). CONCLUSIONS: The reliability of the signs and symptoms examined and the ability of individual investigators to correctly identify and assign signs and symptoms varied widely. The current assessment tools for the qualification of tooth wear need further refinement, and examiners need intensive training in tooth wear assessment.

Scientific Machine Learning of 2D Perovskite Nanosheet Formation.

We apply a scientific machine learning (ML) framework to aid the prediction and understanding of nanomaterial formation processes via a joint spectral-kinetic model. We apply this framework to study the nucleation and growth of two-dimensional (2D) perovskite nanosheets. Colloidal nanomaterials have size-dependent optical properties and can be observed in situ, all of which make them a good model for understanding the complex processes of nucleation, growth, and phase transformation of 2D perovskites. Our results demonstrate that this model nanomaterial can form through two processes at the nanoscale: either via a layer-by-layer chemical exfoliation process from lead bromide nanocrystals or via direct nucleation from precursors. We utilize a phenomenological kinetic analysis to study the exfoliation process and scientific machine learning to study the direct nucleation and growth and discuss the circumstances under which it is more appropriate to use phenomenological or more complex machine learning models. Data for both analysis techniques are collected through in situ spectroscopy in a stopped flow chamber, incorporating over 500,000 spectra taken under more than 100 different conditions. More broadly, our research shows that the ability to utilize and integrate traditional kinetics and machine learning methods will greatly assist in the understanding of complex chemical systems.

Tuning Phonon Energies in Lanthanide-doped Potassium Lead Halide Nanocrystals for Enhanced Nonlinearity and Upconversion.

Optical applications of lanthanide-doped nanoparticles require materials with low phonon energies to minimize nonradiative relaxation and promote nonlinear processes like upconversion. Heavy halide hosts offer low phonon energies but are challenging to synthesize as nanocrystals. Here, we demonstrate the size-controlled synthesis of low-phonon-energy KPb2 X5 (X=Cl, Br) nanoparticles and the ability to tune nanocrystal phonon energies as low as 128 cm-1 . KPb2 Cl5 nanoparticles are moisture resistant and can be efficiently doped with lighter lanthanides. The low phonon energies of KPb2 X5 nanoparticles promote upconversion luminescence from higher lanthanide excited states and enable highly nonlinear, avalanche-like emission from KPb2 Cl5 : Nd3+ nanoparticles. The realization of nanoparticles with tunable, ultra-low phonon energies facilitates the discovery of nanomaterials with phonon-dependent properties, precisely engineered for applications in nanoscale imaging, sensing, luminescence thermometry and energy conversion.

Visuo-tactile heading perception.

Self-motion through an environment induces various sensory signals, i.e., visual, vestibular, auditory, or tactile. Numerous studies have investigated the role of visual and vestibular stimulation for the perception of self-motion direction (heading). Here, we investigated the rarely considered interaction of visual and tactile stimuli in heading perception. Participants were presented optic flow simulating forward self-motion across a horizontal ground plane (visual), airflow toward the participants' forehead (tactile), or both. In separate blocks of trials, participants indicated perceived heading from unimodal visual or tactile or bimodal sensory signals. In bimodal trials, presented headings were either spatially congruent or incongruent with a maximum offset between visual and tactile heading of 30°. To investigate the reference frame in which visuo-tactile heading is encoded, we varied head and eye orientation during presentation of the stimuli. Visual and tactile stimuli were designed to achieve comparable precision of heading reports between modalities. Nevertheless, in bimodal trials heading perception was dominated by the visual stimulus. A change of head orientation had no significant effect on perceived heading, whereas, surprisingly, a change in eye orientation affected tactile heading perception. Overall, we conclude that tactile flow is more important to heading perception than previously thought.NEW & NOTEWORTHY We investigated heading perception from visual-only (optic flow), tactile-only (tactile flow), or bimodal self-motion stimuli in different conditions varying in head and eye position. Overall, heading perception was body or world centered and non-Bayes optimal and revealed a centripetal bias. Although being visually dominated, tactile flow revealed a significant influence during bimodal heading perception.

Local selection signals in the genome of blue tits emphasize regulatory and neuronal evolution.

Understanding the genomic landscape of adaptation is central to understanding microevolution in wild populations. Genomic targets of selection and the underlying genomic mechanisms of adaptation can be elucidated by genome-wide scans for past selective sweeps or by scans for direct fitness associations. We sequenced and assembled 150 haplotypes of 75 blue tits (Cyanistes caeruleus) of a single Central European population by a linked-read technology. We used these genome data in combination with coalescent simulations (i) to estimate an historical effective population size of ~250,000, which recently declined to ~10,000, and (ii) to identify genome-wide distributed selective sweeps of beneficial variants probably originating from standing genetic variation (soft sweeps). The genes linked to these soft sweeps, but also those linked to hard sweeps based on new beneficial mutants, showed a significant enrichment for functions associated with gene expression and transcription regulation. This emphasizes the importance of regulatory evolution in the population's adaptive history. Soft sweeps were further enriched for genes related to axon and synapse development, indicating the significance of neuronal connectivity changes in the brain potentially linked to behavioural adaptations. A previous scan of heterozygosity-fitness correlations revealed a consistent negative effect on arrival date at the breeding site for a single microsatellite in the MDGA2 gene. Here, we used the haplotype structure around this microsatellite to explain the effect as a local and direct outbreeding effect of a gene involved in synapse development.

Tooth Wear Evaluation System (TWES) 2.0-Reliability of diagnosis with and without computer-assisted evaluation.

BACKGROUND: Tooth wear is a multifactorial process, leading to the loss of dental hard tissues. Therefore, it is important to detect the level of tooth wear at an early stage, so monitoring can be initiated. The Tooth Wear Evaluation System (TWES) enables such a multistage diagnosis of tooth wear. The further developed TWES 2.0 contains a complete taxonomy of tooth wear, but its reliability has not yet been validated. OBJECTIVES: The aim of the study was to examine in a randomised controlled trial (RCT) whether diagnoses made based on the TWES 2.0 are reproducible and whether this reproducibility is also achieved with computer-assisted diagnostics. METHODS: 44 dental students received extensive training in TWES 2.0 assessment and taxonomy. The students each evaluated at least 10 (of the present 14) anonymised patient cases using gypsum models and high-resolution intra-oral photographs according to TWES 2.0. One half initially evaluated on paper; the other half used dedicated software (CMDfact / CMDbrux). After half of the patient cases (5), the evaluation methods were switched (AB/BA crossover design). The diagnoses were then evaluated for agreement with the predefined sample solution. RESULTS: Evaluation of agreement with the sample solution according to Cohen's kappa indicated a value of 0.46 for manual (traditional) evaluation; and 0.44 for computer-assisted evaluation. Evaluation of agreement between examiners was 0.38 for manual and 0.48 for computer-assisted evaluation (Fleiss' kappa). CONCLUSION: The results of this study proved that the taxonomy of the TWES 2.0 has acceptable reliability and can thus be used by dentists. Accordingly, the system can be learned quickly even by untrained practitioners. Comparable results are achieved with computer-assisted evaluation.

Perisaccadic encoding of temporal information in macaque area V4.

The accurate processing of temporal information is of critical importance in everyday life. Yet, psychophysical studies in humans have shown that the perception of time is distorted around saccadic eye movements. The neural correlates of this misperception are still poorly understood. Behavioral and neural evidence suggest that it is tightly linked to other known perisaccadic modulations of visual perception. To further our understanding of how temporal processing is affected by saccades, we studied the representations of brief visual time intervals during fixation and saccades in area V4 of two awake macaques. We presented random sequences of vertical bar stimuli and extracted neural responses to double-pulse stimulation at varying interstimulus intervals. Our results show that temporal information about very brief intervals of as brief as 20 ms is reliably represented in the multiunit activity in area V4. Response latencies were not systematically modulated by the saccade. However, a general increase in perisaccadic activity altered the ratio of response amplitudes within stimulus pairs compared with fixation. In line with previous studies showing that the perception of brief time intervals is partly based on response levels, this may be seen as a possible correlate of the perisaccadic misperception of time.NEW & NOTEWORTHY We investigated for the first time how temporal information on very brief timescales is represented in area V4 around the time of saccadic eye movements. Overall, the responses showed an unexpectedly precise representation of time intervals. Our finding of a perisaccadic modulation of relative response amplitudes introduces a new possible correlate of saccade-related perceptual distortions of time.

Action-dependent processing of self-motion in parietal cortex of macaque monkeys.

Successful interaction with the environment requires the dissociation of self-induced from externally induced sensory stimulation. Temporal proximity of action and effect is hereby often used as an indicator of whether an observed event should be interpreted as a result of own actions or not. We tested how the delay between an action (press of a touch bar) and an effect (onset of simulated self-motion) influences the processing of visually simulated self-motion in the ventral intraparietal area (VIP) of macaque monkeys. We found that a delay between the action and the start of the self-motion stimulus led to a rise of activity above the baseline activity before motion onset in a subpopulation of 21% of the investigated neurons. In the responses to the stimulus, we found a significantly lower sustained activity when the press of a touch bar and the motion onset were contiguous compared to the condition when the motion onset was delayed. We speculate that this weak inhibitory effect might be part of a mechanism that sharpens the tuning of VIP neurons during self-induced motion and thus has the potential to increase the precision of heading information that is required to adjust the orientation of self-motion in everyday navigational tasks.NEW & NOTEWORTHY Neurons in macaque ventral intraparietal area (VIP) are responding to sensory stimulation related to self-motion, e.g. visual optic flow. Here, we found that self-motion induced activation depends on the sense of agency, i.e., it differed when optic flow was perceived as self- or externally induced. This demonstrates that area VIP is well suited for study of the interplay between active behavior and sensory processing during self-motion.

Visual perturbation of balance suggests impaired motor control but intact visuomotor processing in Parkinson's disease.

Postural instability marks one of the most disabling features of Parkinson's disease (PD), but it only reveals itself after affected brain areas have already been significantly damaged. Thus there is a need to detect deviations in balance and postural control before visible symptoms occur. In this study, we visually perturbed balance in the anterior-posterior direction using sinusoidal oscillations of a moving room in virtual reality at different frequencies. We tested three groups: individuals with PD under dopaminergic medication, an age-matched control group, and a group of young healthy adults. We tracked their center of pressure and their full-body motion, from which we also extracted the center of mass. We investigated sway amplitudes and applied newly introduced phase-locking analyses to investigate responses across participants' bodies. Patients exhibited significantly higher sway amplitudes as compared with the control subjects. However, their sway was phase locked to the visual motion like that of age-matched and young healthy adults. Furthermore, all groups successfully compensated for the visual perturbation by phase locking their sway to the stimulus. As frequency of the perturbation increased, distribution of phase locking (PL) across the body revealed a shift of the highest PL values from the upper body toward the hip region for young healthy adults, which could not be observed in patients and elderly healthy adults. Our findings suggest an impaired motor control, but intact visuomotor processing in early stages of PD, while less flexibility to adapt postural strategy to different perturbations revealed to be an effect of age rather than disease.NEW & NOTEWORTHY A better understanding of visuomotor control in Parkinson's disease (PD) potentially serves as a tool for earlier diagnosis, which is crucial for improving patient's quality of life. In our study, we assess body sway responses to visual perturbations of the balance control system in patients with early-to-mid stage PD, using motion tracking along with recently established phase-locking techniques. Our findings suggest patients at this stage have an impaired muscular stability but intact visuomotor control.

Elucidating the Weakly Reversible Cs-Pb-Br Perovskite Nanocrystal Reaction Network with High-Throughput Maps and Transformations.

Advances in automation and data analytics can aid exploration of the complex chemistry of nanoparticles. Lead halide perovskite colloidal nanocrystals provide an interesting proving ground: there are reports of many different phases and transformations, which has made it hard to form a coherent conceptual framework for their controlled formation through traditional methods. In this work, we systematically explore the portion of Cs-Pb-Br synthesis space in which many optically distinguishable species are formed using high-throughput robotic synthesis to understand their formation reactions. We deploy an automated method that allows us to determine the relative amount of absorbance that can be attributed to each species in order to create maps of the synthetic space. These in turn facilitate improved understanding of the interplay between kinetic and thermodynamic factors that underlie which combination of species are likely to be prevalent under a given set of conditions. Based on these maps, we test potential transformation routes between perovskite nanocrystals of different shapes and phases. We find that shape is determined kinetically, but many reactions between different phases show equilibrium behavior. We demonstrate a dynamic equilibrium between complexes, monolayers, and nanocrystals of lead bromide, with substantial impact on the reaction outcomes. This allows us to construct a chemical reaction network that qualitatively explains our results as well as previous reports and can serve as a guide for those seeking to prepare a particular composition and shape.

Negative effects of individual heterozygosity on reproductive success in a wild bird population.

The evolutionary consequences of individual genetic diversity are frequently studied by assessing heterozygosity-fitness correlations (HFCs). The prevalence of positive and negative HFCs and the predominance of general versus local effects in wild populations are far from understood, partly because comprehensive studies testing for both inbreeding and outbreeding depression are lacking. We studied a genetically diverse population of blue tits in southern Germany using a genome-wide set of 87 microsatellites to investigate the relationship between proxies of reproductive success and measures of multilocus and single-locus individual heterozygosity (MLH and SLH). We used complimentary measures of MLH and partitioned markers into functional categories according to their position in the blue tit genome. HFCs based on MLH were consistently negative for functional loci, whereas correlations were rather inconsistent for loci found in nonfunctional areas of the genome. Clutch size was the only reproductive variable showing a general effect. We found evidence for local effects for three measures of reproductive success: arrival date at the breeding site, the probability of breeding at the study site and male reproductive success. For these, we observed consistent, and relatively strong, negative effects at one functional locus. Remarkably, this marker had a similar effect in another blue tit population from Austria (~400 km to the east). We suggest that a genetic local effect on timing of arrival might be responsible for most negative HFCs detected, with carry-over effects on other reproductive traits. This effect could reflect individual differences in the distance between overwintering areas and breeding sites.

Genes acting in synapses and neuron projections are early targets of selection during urban colonization.

When a species colonizes an urban habitat, differences in the environment can create novel selection pressures. Successful colonization will further lead to demographic perturbations and genetic drift, which can interfere with selection. Here, we test for consistent urban selection signals in multiple populations of the burrowing owl (Athene cunicularia), a species that colonized South American cities just a few decades ago. We sequenced 213 owls from three urban-rural population pairs and performed a genome-wide comparison of urban against rural birds. We further studied genome-wide associations with flight initiation distance, a measure of harm avoidance in which urban and rural birds are known to differ. Based on four samples taken over nine years from one of the urban populations, we investigated temporal allele frequency changes. The genomic data were also used to identify urban-specific signatures of selective sweeps. Single genomic sites did not reach genome-wide significance for any association. However, a gene-set analysis on the strongest signals from these four selection scans suggests a significant enrichment of genes with known functions related to synapses and neuron projections. We identified 98 genes predominantly expressed in the brain, of which many may play a role in the modulation of brain connectivity and consequently in cognitive function and motivational behaviour during urbanization. Furthermore, polymorphisms in the promoter region of the synaptic SERT gene - one of the two candidates known to correlate with urban colonization in birds - associated with the habitat in which individuals lived (urban vs. rural).

Inter-trial phase coherence of visually evoked postural responses in virtual reality.

Vision plays a central role in maintaining balance. When humans perceive their body as moving, they trigger counter movements. This results in body sway, which has typically been investigated by measuring the body's center of pressure (COP). Here, we aimed to induce visually evoked postural responses (VEPR) by simulating self-motion in virtual reality (VR) using a sinusoidally oscillating "moving room" paradigm. Ten healthy subjects participated in the experiment. Stimulation consisted of a 3D-cloud of random dots, presented through a VR headset, which oscillated sinusoidally in the anterior-posterior direction at different frequencies. We used a force platform to measure subjects' COP over time and quantified the resulting trajectory by wavelet analyses including inter-trial phase coherence (ITPC). Subjects exhibited significant coupling of their COP to the respective stimulus. Even when spectral analysis of postural sway showed only small responses in the expected frequency bands (power), ITPC revealed an almost constant strength of coupling to the stimulus within but also across subjects and presented frequencies. Remarkably, ITPC even revealed a strong phase coupling to stimulation at 1.5 Hz, which exceeds the frequency range that has generally been attributed to the coupling of human postural sway to an oscillatory visual scenery. These findings suggest phase-locking to be an essential feature of visuomotor control.

Definition and severity grading of postoperative lymphatic leakage following inguinal lymph node dissection.

PURPOSE: Lymphatic complications occur frequently after radical inguinal lymph node dissection (RILND). The incidence of lymphatic leakage varies considerably among different studies due to the lack of a consistent definition. The aim of the present study is to propose a standardized definition and grading of different types of lymphatic leakage after groin dissection. METHODS: A bicentric retrospective analysis of 82 patients who had undergone RILND was conducted. A classification of postoperative lymphatic leakage was developed on the basis of the daily drainage output, any necessary postoperative interventions and reoperations, and any delay in adjuvant treatment. RESULTS: In the majority of cases, RILND was performed in patients with inguinal metastases of malignant melanoma (n = 71). Reinterventions were necessary in 15% of the patients and reoperations in 32%. A new classification of postoperative lymphatic leakage was developed. According to this definition, grade A lymphatic leakage (continued secretion of lymphatic fluid from the surgical drains without further complications) occurred in 13% of the patients, grade B lymphatic leakage (persistent drainage for more than 10 postoperative days or the occurrence of a seroma after the initial removal of the drain that requires an intervention) in 28%, and grade C lymphatic leakage (causing a reoperation or a subsequent conflict with medical measures) in 33%. The drainage volume on the second postoperative day was a suitable predictor for a complicated lymphatic leakage (grades B and C) with a cutoff of 110 ml. CONCLUSION: The proposed definition is clinically relevant, is easy to employ, and may serve as the definition of a standardized endpoint for the assessment of lymphatic morbidity after RILND in future studies.

The Making and Breaking of Lead-Free Double Perovskite Nanocrystals of Cesium Silver-Bismuth Halide Compositions.

Replacing lead in halide perovskites is of great interest due to concerns about stability and toxicity. Recently, lead free double perovskites in which the unit cell is doubled and two divalent lead cations are substituted by a combination of mono- and trivalent cations have been synthesized as bulk single crystals and as thin films. Here, we study stability and optical properties of all-inorganic cesium silver(I) bismuth(III) chloride and bromide nanocrystals with the double perovskite crystal structure. The cube-shaped nanocrystals are monodisperse in size with typical side lengths of 8 to 15 nm. The absorption spectrum of the nanocrystals presents a sharp peak, which we assign to a direct bismuth s-p transition and not to a quantum confined excitonic transition. Using this spectroscopic handle combined with high-resolution transmission electron microscopy (TEM) based elemental analysis, we conduct stoichiometric studies at the single nanocrystal level as well as decomposition assays in solution and observe that Ag+ diffusion and coalescence is one of the pathways by which this material degrades. Drying the nanocrystals leads to self-assembly into ordered nanocrystal solids, and these exhibit less degradation than nanocrystals in solution. Our results demonstrate that Cs2AgBiX6 (X = Cl, Br) nanocrystals are a useful model system to study structure-function relationships in the search for stable nontoxic halide perovskites.