Evidence for the association of triatomic molecules in ultracold 23Na40K + 40K mixtures.

Ultracold assembly of diatomic molecules has enabled great advances in controlled chemistry, ultracold chemical physics and quantum simulation with molecules1-3. Extending the ultracold association to triatomic molecules will offer many new research opportunities and challenges in these fields. A possible approach is to form triatomic molecules in a mixture of ultracold atoms and diatomic molecules by using a Feshbach resonance between them4,5. Although ultracold atom-diatomic-molecule Feshbach resonances have been observed recently6,7, using these resonances to form triatomic molecules remains challenging. Here we report on evidence of the association of triatomic molecules near the Feshbach resonance between 23Na40K molecules in the rovibrational ground state and 40K atoms. We apply a radio-frequency pulse to drive the free-bound transition in ultracold mixtures of 23Na40K and 40K and monitor the loss of 23Na40K molecules. The association of triatomic molecules manifests itself as an additional loss feature in the radio-frequency spectra, which can be distinguished from the atomic loss feature. The observation that the distance between the association feature and the atomic transition changes with the magnetic field provides strong evidence for the formation of triatomic molecules. The binding energy of the triatomic molecules is estimated from the measurements. Our work contributes to the understanding of the complex ultracold atom-molecule Feshbach resonances and may open up an avenue towards the preparation and control of ultracold triatomic molecules.

A subradiant optical mirror formed by a single structured atomic layer.

Versatile interfaces with strong and tunable light-matter interactions are essential for quantum science1 because they enable mapping of quantum properties between light and matter1. Recent studies2-10 have proposed a method of controlling light-matter interactions using the rich interplay of photon-mediated dipole-dipole interactions in structured subwavelength arrays of quantum emitters. However, a key aspect of this approach-the cooperative enhancement of the light-matter coupling strength and the directional mirror reflection of the incoming light using an array of quantum emitters-has not yet been experimentally demonstrated. Here we report the direct observation of the cooperative subradiant response of a two-dimensional square array of atoms in an optical lattice. We observe a spectral narrowing of the collective atomic response well below the quantum-limited decay of individual atoms into free space. Through spatially resolved spectroscopic measurements, we show that the array acts as an efficient mirror formed by a single monolayer of a few hundred atoms. By tuning the atom density in the array and changing the ordering of the particles, we are able to control the cooperative response of the array and elucidate the effect of the interplay of spatial order and dipolar interactions on the collective properties of the ensemble. Bloch oscillations of the atoms outside the array enable us to dynamically control the reflectivity of the atomic mirror. Our work demonstrates efficient optical metamaterial engineering based on structured ensembles of atoms4,8,9 and paves the way towards controlling many-body physics with light5,6,11 and light-matter interfaces at the single-quantum level7,10.

N-linked glycoproteins and host proteases are involved in swine acute diarrhea syndrome coronavirus entry.

IMPORTANCE: Gaining insight into the cell-entry mechanisms of swine acute diarrhea syndrome coronavirus (SADS-CoV) is critical for investigating potential cross-species infections. Here, we demonstrated that pretreatment of host cells with tunicamycin decreased SADS-CoV attachment efficiency, indicating that N-linked glycosylation of host cells was involved in SADS-CoV entry. Common N-linked sugars Neu5Gc and Neu5Ac did not interact with the SADS-CoV S1 protein, suggesting that these molecules were not involved in SADS-CoV entry. Additionally, various host proteases participated in SADS-CoV entry into diverse cells with different efficiencies. Our findings suggested that SADS-CoV may exploit multiple pathways to enter cells, providing insights into intervention strategies targeting the cell entry of this virus.

Observation of Photoassociation Resonances in Ultracold Atom-Molecule Collisions.

We report on the observation of photoassociation resonances in ultracold collisions between ^{23}Na^{40}K molecules and ^{40}K atoms. We perform photoassociation in a long-wavelength optical dipole trap to form deeply bound triatomic molecules in electronically excited states. The atom-molecule Feshbach resonance is used to enhance the free-bound Franck-Condon overlap. The photoassociation into well-defined quantum states of excited triatomic molecules is identified by observing resonantly enhanced loss features. These loss features depend on the polarization of the photoassociation lasers, allowing us to assign rotational quantum numbers. The observation of ultracold atom-molecule photoassociation resonances paves the way toward preparing ground-state triatomic molecules, provides a new high-resolution spectroscopy technique for polyatomic molecules, and is also important to atom-molecule Feshbach resonances.

Electroweak Corrections to Double Higgs Production at the LHC.

We present the results for the complete next-to-leading order electroweak corrections to pp→HH at the Large Hadron Collider, focusing on the dominant gluon-gluon fusion process. While the corrections at the total cross-section level are approximately -4%, those near the energy of HH production threshold exceed +15%, and corrections at the high-energy region are around -10%, leading to a shape distortion for the differential distributions. Our findings substantially diminish the theoretical uncertainties associated with this pivotal process, providing valuable input for understanding the shape of the Higgs boson potential upon comparison with experimental measurements.

The potential of Rhein's aromatic amines for Parkinson's disease prevention and treatment: α-Synuclein aggregation inhibition and disaggregation of preformed fibers.

The aggregation of α-Syn is a pivotal mechanism in Parkinson's disease (PD). Effectively maintaining α-Syn proteostasis involves both inhibiting its aggregation and promoting disaggregation. In this study, we developed a series of aromatic amide derivatives based on Rhein. Two of these compounds, 4,5-dihydroxy-N-(3-hydroxyphenyl)-9,10-dioxo-9,10-dihydroanthracene-2-carboxamide (a5) and 4,5-dihydroxy-N-(2-hydroxy-4-chlorophenyl)-9,10-dioxo-9,10-dihydroanthracene-2-carboxamide (a8), exhibited good binding affinities to α-Syn residues, demonstrating promising inhibitory activity against α-Syn aggregation in vitro, with low IC50 values (1.35 and 1.08 µM, respectivly). These inhibitors acted throughout the entire aggregation process by stabilizing α-Syn's conformation and preventing the formation of ß-sheet aggregates. They also effectively disassembled preformed α-Syn oligomers and fibrils. Preliminary mechanistic insights indicated that they bound to the specific domain within fibrils, inducing fibril instability, collapse, and the formation of smaller aggregates and monomeric α-Syn units. This research underscores the therapeutic potential of Rhein's aromatic amides in targeting α-Syn aggregation for PD treatment and suggests broader applications in managing and preventing neurodegenerative diseases.

Reduced microbial stability in the active layer is associated with carbon loss under alpine permafrost degradation.

Permafrost degradation may induce soil carbon (C) loss, critical for global C cycling, and be mediated by microbes. Despite larger C stored within the active layer of permafrost regions, which are more affected by warming, and the critical roles of Qinghai-Tibet Plateau in C cycling, most previous studies focused on the permafrost layer and in high-latitude areas. We demonstrate in situ that permafrost degradation alters the diversity and potentially decreases the stability of active layer microbial communities. These changes are associated with soil C loss and potentially a positive C feedback. This study provides insights into microbial-mediated mechanisms responsible for C loss within the active layer in degraded permafrost, aiding in the modeling of C emission under future scenarios.

Two new anti-inflammatory trachylobane diterpenoids from Euphorbia atoto.

Two new rare trachylobane euphoratones A-B (1-2), together with five known diterpenoids (compounds 3-7), were isolated from the aerial parts of Euphorbia atoto. Their structures were unambiguously elucidated through HRESIMS, 1D and 2D NMR spectral analysis. Compounds 1, 3, 4 and 7 showed weak anti-inflammatory activities (IC50 77.49 ± 6.34, 41.61 ± 14.49, 16.00 ± 1.71 and 33.41 ± 4.52 µM, respectively), compared to the positive control quercetin (IC50 15.23 ± 0.65 µM).

Comparison of genomic prediction methods for early growth traits of Inner Mongolia cashmere goats based on multi trait models.

Inner Mongolia cashmere goat is an excellent livestock breed formed through long-term natural selection and artificial breeding, and is currently a world-class dual-purpose breed producing cashmere and meat. Multi trait animal model is considered to significantly improve the accuracy of genetic evaluation in livestock and poultry, enabling indirect selection between traits. In this study, the pedigree, genotype, environment, and phenotypic records of early growth traits of Inner Mongolia cashmere goats were used to build multi trait animal model., Then three methods including ABLUP, GBLUP, and ssGBLUP wereused to estimate the genetic parameters and genomic breeding values of early growth traits (birth weight, weaning weight, average daily weight gain before weaning, and yearling weight). The accuracy and reliability of genomic estimated breeding value are further evaluated using the five fold cross validation method. The results showed that the heritability of birth weight estimated by three methods was 0.13-0.15, the heritability of weaning weight was 0.13-0.20, heritability of daily weight gain before weaning was 0.11-0.14, and the heritability of yearling weight was 0.09-0.14, all of which belonged to moderate to low heritability. There is a strong positive genetic correlation between weaning weight and daily weight gain before weaning, daily weight gain before weaning and yearling weight, with correlation coefficients of 0.77-0.79 and 0.56-0.67, respectively. The same pattern was found in phenotype correlation among traits. The accuracy of the estimated breeding values by ABLUP, GBLUP, and ssGBLUP methods for birth weight is 0.5047, 0.6694, and 0.7156, respectively; the weaning weight is 0.6207, 0.6456, and 0.7254, respectively; the daily weight gain before weaning was 0.6110, 0.6855, and 0.7357 respectively; and the yearling weight was 0.6209, 0.7155, and 0.7756, respectively. In summary, the early growth traits of Inner Mongolia cashmere goats belong to moderate to low heritability, and the speed of genetic improvement is relatively slow. The genetic improvement of other growth traits can be achieved through the selection of weaning weight. The ssGBLUP method has the highest accuracy and reliability in estimating genomic breeding value of early growth traits in Inner Mongolia cashmere goats, and is significantly higher than that from ABLUP method, indicating that it is the best method for genomic breeding of early growth weight in Inner Mongolia cashmere goats.

[Mechanism of Kuntai Capsules in treatment of polycystic ovary syndrome rat models based on AGE-RAGE signal pathway].

This study aims to investigate the impact of Kuntai Capsules(KTC) on polycystic ovarian syndrome(PCOS) rat models and explore the underlying mechanism. Fifty female SD rats were randomly divided into five groups(10 rats in each group), including control group, model group, low-, medium-, and high-dose KTC group. Except for the control group, the other groups were injected with dehydroepiandrosterone(DHEA) combined with a high-fat diet(HFD) to induce the PCOS rat model for 28 days. 0.315, 0.63, and 1.26 g·kg~(-1)·d~(-1) KTC was dissolved in the same amount of normal saline and given to low-, medium-, and high-dose KTC groups by gavage. Both control group and model group were given the same amount of normal saline for 15 days. After administration, fasting blood glucose(FBG) was measured by a glucose meter. Fasting insulin(FINS), luteinizing hormone(LH), testosterone(T), and follicle-stimulating hormone(FSH) were detected by enzyme-linked immunosorbent assay(ELISA), and LH/FSH ratio and insulin resistance index(HOMA-IR) were calculated. The pathological morphology of ovarian tissue was observed by hematoxylin-eosin(HE) staining. The expression levels of collagen α type Ⅲ 1 chain(COL3A1), apoptotic factors Bax, and Bcl-2 were detected using Western blot and immunofluorescence. The mRNA expressions of COL3A1, Bax, and Bcl-2 in ovarian tissue were performed by real-time PCR(RT-PCR). The results show that compared with the control group, the body weight, serum levels of FBG, FINS, LH, T, LH/FSH, and HOMA-IR are higher in model group(P<0.05 or P<0.01), and the level of FSH is lower(P<0.05). In model group, a large number of white blood cells are found in the vaginal exfoliated cells, mainly in the interictal phase. There are more cystic prominences on the surface of the ovary. The thickness of the granular cell layer is reduced, and oocytes are absent. COL3A1 and Bax protein expression levels are increased(P<0.01), while Bcl-2 protein expression levels are decreased(P<0.05) in the ovarian tissue COL3A1 and Bax mRNA expression levels are increased in ovarian tissue(P<0.05). Compared with the model group, the body weight, FBG, FINS, LH, T, LH/FSH, and HOMA-IR in low-, medium-, and high-dose KTC groups are decreased(P<0.05 or P<0.01), while the levels of FSH in medium-, and high-dose KTC groups are increased(P<0.05 or P<0.01). Low-, medium-, and high-dose KTC groups gradually show a stable interictal phase. The surface of the ovary is smooth. Oocytes and mature follicles can be seen in ovarian tissue, and the thickness of the granular cell layer is increased. The expression level of COL3A1 protein decreases in low-and medium-dose KTC groups(P<0.05 or P<0.01), and that of Bax protein decreases in low-dose KTC group(P<0.05 or P<0.01), and the expression level of Bcl-2 protein increases in low-dose KTC group(P<0.01). The expression levels of COL3A1 and Bax mRNA decreased in the low-dose KTC group(P<0.05), while the expression levels of Bcl-2 mRNA increased(P<0.05). In summary, KTC can inhibit ovarian granulosa cell apoptosis and reduce follicular atresia by regulating the AGE-RAGE signaling pathway. It can promote insulin secretion, reduce blood sugar and body weight, restore serum hormone levels, improve symptoms of PCOS, alleviate morphological damage of the ovary, and restore ovarian function, which is of great value in the treatment of PCOS.

Regioselective ortho C-H insertion of N-nitrosoanilines with naphthoquinone carbenes.

A Rh(III)-catalyzed ortho C-H migratory insertion of N-nitrosoanilines with naphthoquinone carbenes has been developed. The products were obtained in good yields under mild reaction conditions. Diverse elaborations of the products were explored. This method is valuable for the synthesis of biarylamines and their derivatives.

4-Arylidene curcumin derivatives in vitro inhibit α-Synuclein aggregation and disaggregate the preformed fibril.

This study focuses on the misfolding and aggregation of α-Syn as a central mechanism linking various pathological processes in PD. Maintaining α-Syn proteostasis through suitable inhibitors emerges as an effective approach to prevent PD. A more efficient strategy for PD treatment involves disintegrating neurotoxic oligomers and fibrils into normal functional α-Syn using inhibitors. To this end, a series of 4-arylidene curcumin derivatives were synthesized with a sheet-like conjugated skeleton and higher binding energies with α-Syn residues. Among these derivatives, three candidate compounds exhibited promising α-Syn aggregation inhibitory activities in vitro, with IC50 values as low as 0.61 µM. The inhibitory action extended throughout the entire aggregation process, stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation. Furthermore, the candidate compounds demonstrated effective disintegration capabilities against preformed α-Syn oligomers and fibrils. Initial mechanistic investigations indicated that the inhibitors may bind to a specific domain within the fibril, inducing fibril instability and subsequent collapse. This process resulted in the formation of a complex system of aggregates with smaller sizes and monomers. Overall, these findings provide valuable insights into the potential of 4-arylidene curcumin derivatives as therapeutic agents for targeting α-Syn aggregation in PD treatment.

Group V Chitin Deacetylases Influence the Structure and Composition of the Midgut of Beet Armyworm, Spodoptera exigua.

Chitin deacetylase (CDA) can accelerate the conversion of chitin to chitosan, influencing the mechanical properties and permeability of the cuticle structures and the peritrophic membrane (PM) in insects. Putative Group V CDAs SeCDA6/7/8/9 (SeCDAs) were identified and characterized from beet armyworm Spodoptera exigua larvae. The cDNAs of SeCDAs contained open reading frames of 1164 bp, 1137 bp, 1158 bp and 1152 bp, respectively. The deduced protein sequences showed that SeCDAs are synthesized as preproteins of 387, 378, 385 and 383 amino acid residues, respectively. It was revealed via spatiotemporal expression analysis that SeCDAs were more abundant in the anterior region of the midgut. The SeCDAs were down-regulated after treatment with 20-hydroxyecdysone (20E). After treatment with a juvenile hormone analog (JHA), the expression of SeCDA6 and SeCDA8 was down-regulated; in contrast, the expression of SeCDA7 and SeCDA9 was up-regulated. After silencing SeCDAV (the conserved sequences of Group V CDAs) via RNA interference (RNAi), the layer of intestinal wall cells in the midgut became more compact and more evenly distributed. The vesicles in the midgut were small and more fragmented or disappeared after SeCDAs were silenced. Additionally, the PM structure was scarce, and the chitin microfilament structure was loose and chaotic. It was indicated in all of the above results that Group V CDAs are essential for the growth and structuring of the intestinal wall cell layer in the midgut of S. exigua. Additionally, the midgut tissue and the PM structure and composition were affected by Group V CDAs.

Analysis of genetic diversity and genetic structure of Qinchuan cattle conservation population using whole-genome resequencing.

In the conservation of livestock and poultry resources, population genetic diversity and genetic structure of the conservation population are important factors affecting the effectiveness of conservation. In this study, whole-genome resequencing technology was used to detect genomic variation in 100 Qinchuan cattle (30 bulls and 70 cows). By analyzing population genetic diversity, runs of homozygosity (ROH) distribution features, kinship relationships, and family structure, the conservation effectiveness of Qinchuan cattle was comprehensively evaluated. The results showed that a total of 20,968,017 high-quality SNPs were detected in 100 Qinchuan cattle, the average minimum allele frequency was 0.191±0.124, the average polymorphic information content was 0.279±0.131, and the average observed heterozygosity was 0.275±0.131, the average expected heterozygosity is 0.279±0.131, indicating that the genetic diversity of the Qinchuan cattle conservation population is relatively rich. The average identity by state (IBS) distance of the Qinchuan conservation population was 0.243±0.020, with a value of 0.242±0.021 for the bulls. The results of the kinship G-matrix were consistent with the results of the IBS distance matrix, both showing that some individuals in the conservation population had close kinship. A total of 8258 genomic ROH were detected in 100 Qinchuan cattle, with a total length of 9.64 GB. The average length of ROH fragments was 1.167±1.203 Mb, 69.35% of the ROH were short ROH with a length of 0.5~1 Mb, and the average total length of ROH per individual was 96.40 Mb. The average inbreeding coefficient based on ROH was 0.039±0.039, with a value of 0.044±0.035 for the bulls, indicating that some bulls had a certain degree of inbreeding accumulation. The results of the phylogenetic tree combined with kinship analysis showed that the individuals in the Qinchuan cattle conservation population could be divided into eight families, including seven families with bulls and one family without bulls. This study demonstrated that the genetic diversity of the Qinchuan conservation population is relatively rich, with no significant inbreeding accumulation, but there is a risk of inbreeding among some individuals. Therefore, it is necessary to strengthen selection and mating to ensure the sustainable development of Qinchuan cattle resources.

Impact of 9-Minute Withdrawal Time on the Adenoma Detection Rate: A Multicenter Randomized Controlled Trial.

BACKGROUND & AIMS: Although current quality indicators of colonoscopy recommend 6 minutes as the minimum standard for withdrawal time (WT), the impact of a WT longer than 6 minutes on neoplasia detection is unclear. METHODS: A multicenter randomized controlled trial involving 1027 patients was conducted from January 2018 to July 2019. Participants were randomly divided into a 9-minute (n = 514) and 6-minute (n = 513) WT group, and a timer was used to adjust the withdrawal speed. The primary outcome was the adenoma detection rate (ADR). RESULTS: Intention-to-treat analysis showed a significantly higher ADR in the 9-minute versus 6-minute WT group (36.6% vs. 27.1%, P = .001). Prolonging WT from 6 to 9 minutes significantly increased ADR of the proximal colon (21.4% vs. 11.9%, P < .001) as well as of the less experienced colonoscopists (36.8% vs. 23.5%, P = .001). Improvements were also observed in the polyp detection rate (58.0% vs. 47.8%, P < .001), and mean number of polyps and adenomas detected per colonoscopy (1.1 vs. 0.9, P = .002; 0.5 vs. 0.4, P = .008, respectively). The higher ADRs in 9-minute WT were also confirmed by the per-protocol (PP) analysis and subgroup analyses, with an increased rate of sessile serrated lesion detection in the 9-minute WT by PP analysis (4.0% vs. 1.3%, P = .04). Multivariate logistic regression demonstrated that the 9-minute WT was independently associated with increased ADR (P = .005). CONCLUSIONS: Prolonging WT from 6 to 9 minutes significantly improved ADR, especially in the proximal colon and for less experienced colonoscopists. A 9-minute WT benchmark should be considered as one of the quality indicators of colonoscopy. ClinicalTrials.gov (identifier, NCT03399045).

Resonant Control of Elastic Collisions between

We have demonstrated the resonant control of the elastic scattering cross sections in the vicinity of Feshbach resonances between ^{23}Na^{40}K molecules and ^{40}K atoms by studying the thermalization between them. The elastic scattering cross sections vary by more than 2 orders of magnitude close to the resonance, and can be well described by an asymmetric Fano profile. The parameters that characterize the magnetically tunable s-wave scattering length are determined from the elastic scattering cross sections. The observation of resonantly controlled elastic scattering cross sections opens up the possibility to study strongly interacting atom-molecule mixtures and improve our understanding of the complex atom-molecule Feshbach resonances.

Realizing Distance-Selective Interactions in a Rydberg-Dressed Atom Array.

Measurement-based quantum computing relies on the rapid creation of large-scale entanglement in a register of stable qubits. Atomic arrays are well suited to store quantum information, and entanglement can be created using highly-excited Rydberg states. Typically, isolating pairs during gate operation is difficult because Rydberg interactions feature long tails at large distances. Here, we engineer distance-selective interactions that are strongly peaked in distance through off-resonant laser coupling of molecular potentials between Rydberg atom pairs. Employing quantum gas microscopy, we verify the dressed interactions by observing correlated phase evolution using many-body Ramsey interferometry. We identify atom loss and coupling to continuum modes as a limitation of our present scheme and outline paths to mitigate these effects, paving the way towards the creation of large-scale entanglement.

Rh(III)-Catalyzed ortho C-H functionalization of aromatic amides with bis(phenylsulfonyl)diazomethane and α-diazosulfones.

A Rh(III)-catalyzed migratory insertion of bis(phenylsulfonyl) carbene and α-sulfonyl carbenes into ortho C-H bonds of aryl amides has been developed. The products were obtained with moderate to excellent yields under mild reaction conditions. A reaction mechanism was proposed based on the control experiments and previous studies. Diverse desulfonylation transformations of the products were achieved.

Prognostic value of a nomogram based on peripheral blood immune parameters in unresectable hepatocellular carcinoma after intensity-modulated radiotherapy.

BACKGROUND: For patients with unresectable hepatocellular carcinoma (uHCC), intensity-modulated radiotherapy (IMRT) has become one of the options for clinical local treatment. Immune parameters, including platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR) and systemic immune inflammatory (SII), predict survival in various cancers. This study aimed to determine whether peripheral immune parameters can predict survival in patients with uHCC undergoing IMRT and establish a clinically useful prognostic nomogram for survival prediction. METHODS: The clinical data of 309 HCC patients were retrospectively analyzed and randomly divided into training (n = 216) and validation (n = 93) cohorts. PLR, NLR and SII were collected before and after IMRT. Univariate and multivariate Cox analyses were performed to identify independent prognostic factors affecting survival, which were used to generate a nomogram. RESULTS: The median survival was 16.3 months, and significant increases in PLR, NLR, and SII were observed after IMRT (P < 0.001). High levels of immune parameters were associated with poor prognosis (P < 0.001); enlarged spleen, Barcelona clinic liver cancer stage (B and C), post-SII, and delta-NLR were independent risk factors for survival and were included in the nomogram, which accurately predicted 3- and 5-year survival. The nomogram was well verified in the validation cohort. CONCLUSIONS: High levels of immune parameters are associated with poor prognosis in uHCC patients receiving IMRT. Our nomogram accurately predicts the survival of patients with uHCC receiving IMRT.

Laryngoscopic findings of age-related vocal fold atrophy are reliable but not specific.

OBJECTIVES: We aimed to evaluate the reliability of laryngoscopic features of vocal fold atrophy as assessed by novice otolaryngology trainees and expert laryngologists. DESIGN: Two expert fellowship-trained laryngologists and three non-expert otolaryngology resident trainees were recruited to view 50 anonymised laryngo-stroboscopic examinations of patients presenting with dysphonia and non-voice, laryngeal complaints. Reviewers were asked to stratify the patient's age, provide an opinion about the presence of age-related vocal fold atrophy and specify which laryngoscopy features were present to make the diagnosis. SETTING: Tertiary care laryngology practice. PARTICIPANTS: Two fellowship-trained laryngologists and three trainee otolaryngologists. MAIN OUTCOME MEASURES: Accuracy of age categorisation was determined and Kappa analysis was performed to assess inter-rater agreement. RESULTS: The mean age of patients was 54.9 years old with near equal male to female distribution. The overall accuracy of age category determination by raters was only 30.8%. Kappa analysis demonstrated fair agreement regarding the presence of vocal fold atrophy in non-expert reviewers, and moderate agreement amongst expert reviewers. Features of glottic gap, muscular atrophy of vocal folds and prominent vocal processes were all identified with high agreement (>80.0%). CONCLUSION: Our study illustrates that while raters can agree on the presence of age-related vocal fold atrophy, the findings may be non-specific and do not necessarily correlate with age.