The decays of B mesons to the K_S^0 ηγ final state constitute flavor-changing neutral current b → s γ transitions, which are forbidden at tree level in the Standard Model and occur via higher-order loop diagrams. Such decays are sensitive to physics beyond the Standard Model due to the potential contribution of new particles in the loops. This report presents a preliminary study of charge-parity violation in B → K_S^0 ηγ decays, performed using Monte Carlo simulations to estimate the expected signal sensitivity for the dataset expected by Belle II in the future.

We investigate the in-medium masses and magnetic moments of decuplet baryons (Δ,Σ^*,Ξ^*,Ω^-) in isospin asymmetric magnetized strange matter at finite temperature within a unified chiral effective framework. Medium modifications of baryons are implemented using the chiral SU(3) quark mean-field (CQMF) model, where constituent quarks interact via scalar (σ, ζ, δ) and vector (ω, ρ, ϕ) meson fields considering the Dirac sea effects. The external magnetic field is incorporated through Landau quantization of charged particles together with anomalous magnetic moments (AMM) of baryons. The resulting in-medium mass of constituent quarks and decuplet baryons obtained from the CQMF model are subsequently employed as input to the chiral constituent quark model (χCQM) to evaluate magnetic moments of baryons. Contributions from valence quarks, sea quark spin polarizations, and orbital angular momentum of the quark sea are taken into account. Our results provide a systematic understanding of how dense, hot, and magnetized environments influence the magnetic properties of decuplet baryons.

We investigate the in-medium properties of pion in the light-front quark model, using the in-medium quark masses computed by chiral SU(3) quark mean field model. We calculate the decay constant and distribution amplitude of the pion in an asymmetric nuclear medium. Utilizing these findings, we derive the transition form factor (TFF) for the process γ ^*γ→π _0 in asymmetric nuclear medium. We compare our free space and in-medium TFF results with the available experimental result, which is found to be in qualitative agreement. This work contributes valuable insights into the behavior of pion within nuclear environments.

We investigate the magnetic moments of octet baryons in isospin asymmetric strange hadronic matter under strong external magnetic fields within a unified theoretical framework by combining the chiral SU(3) quark mean field (CQMF) model with the chiral constituent quark (χCQM) model. At finite temperature, the inclusion of Dirac sea (DS) effect leads to magnetic catalysis attributing to the enhancement of scalar condensates with increasing magnetic field strength. As a consequence, the effective masses of the octet baryons exhibit a monotonic increase as a function of magnetic field. The results highlight the crucial role of vacuum polarization effects in determining the electromagnetic properties of baryons in strongly magnetized matter having relevance in heavy-ion collision and compact stars.

In this work, we investigate the valence quark parton distribution functions (PDFs) of the pion within the light-cone quark model. The initial quark PDFs are calculated by solving the quark-quark correlation function for the pseudoscalar mesons. The initial quark PDFs have been evolved to higher energy scales through the Dokshitzer,Gribov,Lipatov,Altarelli,Parisi (DGLAP) evolution equations. We also find that our calculated evolved PDFs match experimental and available theoretical extraction data. For the first time, we have also predicted the F_2 structure function at next-to-leading (NLO) order accuracy. The calculated F_2 structure function has been compared with the available ZEUS and H1 experimental data at DESY-HERA over a wide range of energy scales. Additionally, we display the forward pion production cross-section for the Drell-Yan process caused by pions using the pion PDFs that were calculated and the target nucleon PDFs from the LHAPDF nucleus datasets. The evolved F_2 structure function of the pion have been studied at the upcoming electron-ion collider energy kinematics. Overall, it was observed that the quark PDFs of pions computed using the light-cone quark model consistent with the experimental results.

Understanding the novel QCD phenomenon under high external magnetic fields of hot and dense medium help us to develop a better understanding of the underlying quark dynamics of baryons. Using a hybrid approach based on the effective field theory that treats quarks as the fundamental degrees of freedom and calculating the individual contribution of valence, sea and orbital angular moment of sea quark, the magnetic moment of a given baryon of the decuplet family is calculated. The incorporation of Landau quantization in the vector and scalar densities of baryons help us to obtain the impact of external magnetic field on the properties of baryons within the chiral SU(3) quark mean field model (CQMF). In the present study, effective masses of the baryons are calculated using CQMF while the framework of chiral constituent quark model (χCQM), extended to SU(4) sector, is used to obtain the effective magnetic moments of decuplet baryons under the influence of magnetic field.

In this study, we have calculated the effective magnetic moments of decuplet baryons as a function of external magnetic field for different values of the baryonic densities focusing on ^- baryon in particular. The impact of the magnetic field has been realised through the chiral SU(3) quark mean field model which considers quarks as the fundamental degrees of freedom. We have studied the impact of varying the magnetic fields on the quark masses and hence the masses of the decuplet baryons and have used these masses as an input to calculate individual contributions coming from valence quarks, quark sea and orbital angular momentum of the quark sea towards the total magnetic moment of the decuplet baryons. These individual contributions have been calculated using chiral constituent quark model. Studying the magnetic moment of baryons provides crucial insights into their internal quark structure and interactions thus helping to refine models of strong force dynamics.

In the present work, we have studied the space-like baryon Sachs form factors in the isospin asymmetric nuclear medium using the vector meson dominance (VMD) model. The in-medium effects are incorporated through the medium-modified masses of vector mesons which are calculated using the QCD sum rule approach taking density dependent scalar quark and gluon condensates as inputs from chiral SU(3) quark mean field (CQMF) model. The effective magnetic moments of the baryons are also calculated in the CQMF model. In the framework of VMD model, the photon couples to the nucleons through intermediary vector mesons with the same quantum number as that of a photon. This coupling leads to the relation of isoscalar and isovector Dirac and Pauli form factors which are then used to calculate the Sachs electric and magnetic form factors, which provide physically measurable quantities that represent the electric and magnetic distributions of the baryons. The present work aims to study the effects of asymmetric nuclear matter at finite temperature on the Sachs form factors of baryons in the space-like region. The electric and magnetic charge radii have also been calculated for the baryons in free space and dense asymmetric nuclear matter. The results obtained have been compared with other available phenomenological models, lattice simulations, and experimental data.

In this study we have investigated the magnetic moments of octet baryons (proton) by examining the direct impact of external magnetic fields on their constituent quarks. Strong external magnetic fields can influence chiral symmetry breaking or its restoration, leading to changes in effective quark masses. We have calculated the effective masses of constituent quarks and the octet baryons in the nuclear matter within the chiral SU(3) quark mean field model and have used these as the input in SU(4) constituent chiral quark model to compute the effective magnetic moments of octet baryons. Unlike the approaches that treat the baryons as single entity, the current approach treats quarks as the degrees of freedom hence, we have calculated and incorporated the individual contributions coming from valence quarks, quark sea and orbital angular momentum of quark sea towards the total magnetic moment of baryons in the varying values of external magnetic fields.

In the present work, we investigated the impact of the finite density of the nuclear medium on the properties of kaons and antikaons. We employed the combined approach of chiral SU(3) quark mean field (CQMF) model and light-cone quark model (LCQM). In the LCQM, weak decay constant and the distribution amplitudes (DAs) of valence quarks are expressed in terms of constituent quark masses. We evaluated the in-medium masses of constituent quarks in the dense nuclear matter using the CQMF model and used those as input in LCQM to investigate the medium-modified properties of K = (K^+, K^0) and K̅ = ( K^-, K̅^0 ) mesons. The impact of finite isospin asymmetry and temperature is also explored.

We investigate the impact of an external magnetic field on the in-medium properties of pseudoscalar (D^0,D^+,D_s) and vector (D^0*,D^+*,D_s^*) mesons in isospin asymmetric nuclear matter at finite temperature using a hybrid theoretical framework combining the chiral SU(3) quark mean-field (CQMF) model and the light-front quark model (LFQM). The medium-modified constituent quark masses, obtained from the CQMF model by including the magnetized Dirac sea contribution and anomalous magnetic moments of nucleons, are used as input to the LFQM calculations of meson masses, weak decay constants, and leading-twist distribution amplitudes. We further incorporate the Landau quantization of the charged mesons restricted to the lowest Landau level, while magnetic field induced pseudoscalar-vector mixing is taken into account for each D-D^* doublet. We find that the external magnetic field enhances the effective masses and decay constants of both pseudoscalar and vector D mesons by magnetic catalysis, while increasing baryon density generally induces an attractive mass shift and suppresses the decay constant and distribution amplitudes. The Landau level contribution further enhances the effective masses of the charged mesons, whereas the pseudoscalar-vector mixing produces a level repulsion, shifting the vector meson masses upward and the pseudoscalar meson masses downward. The interplay between magnetic field and density effects gives rise to a nontrivial medium behavior of heavy-light meson properties, with isospin asymmetry further inducing a small but systematic mass splitting across all the meson states considered. These results provide useful insights into heavy-flavor dynamics in strongly interacting matter and are relevant to ongoing and future studies at FAIR, NICA, and J-PARC.

This study investigates the medium modifications of the magnetic moments and transition properties of low-lying spin-parity J^P = 1/2^- and3/2^- resonances, suchas (1405) with1/2^- and (1520) with3/2^-, inhotanddensehadronicmatterusingthechiralSU(3) quarkmeanfieldmodel. Inthismodel, quarksconfinedinsidethebaryonsaremodifiedthroughtheexchangeofscalarfieldsσ , ζ , andδ andvectorfieldsω , ρ , andϕ which results in shift in quark masses and interaction energies. By analyzing these field-induced modifications, the model enables us to calculate the effective masses and magnetic moments of the quarks and to estimate the impact on the magnetic moments and transition properties of resonances in high density environments.

In the present work we calculate the transition magnetic moments for the radiative decays of Δ baryon to proton (Δ→ p) in isospin asymmetric nuclear medium at finite temperature using chiral SU(3) quark mean field model. Within the framework of chiral SU(3) mean field model, the properties of baryons in asymmetric medium are modified through the exchange of scalar fields (σ, ζ, δ) and vector fields (ω, ρ). The isospin asymmetry of medium is taken into account via scalar-isovector field δ and vector iso-vector field ρ. We calculate the in-medium masses of quarks, proton and Δ baryon in asymmetric matter within the chiral SU(3) quark mean field model and use these as input in the chiral constituent quark (χCQM) model to calculate the in-medium transition magnetic moments for (Δ→ p) transition for different values of isospin asymmetry of hot and dense medium. For calculating the magnetic moments of baryons, contributions of valence quarks, quark sea and orbital angular momentum of quark sea are considered in these calculations.

Abstract Background Despite known side effects, oral steroid use (Hydrocortisone) remains prevalent in the management of inflammatory bowel disease (IBD). We hypothesize that steroid use is multifactorial – historical practices, easy access, and quick response, are some factors that may explain the “overuse” of these medications. We sought to quantify and explore patterns and predictors of steroid use in real world IBD care. Methods Crohn’s Colitis Care (CCCare) is a cloud-based IBD-specific electronic medical record (EMR) used in Australia and New Zealand. Deidentified data prospectively entered by clinicians and consumers were retrospectively analysed, including people with an IBD assessment in the last 14 months. Data were extracted on 15th August 2024. Steroid exposure was defined as short (1-28 days), moderate (29-56 days), or prolonged (>56 days). Recency was defined as recent (within 365 days), previous (365-1085 days), or no exposure. Stepwise logistic regression was used to explore relationships amongst steroid use and demographic and/or disease characteristics. Results In 5441 eligible people, most had Crohn’s disease (CD) 3136 (57.6%), 2165(39.7%) had ulcerative colitis (UC) and 135 (2.4%) IBD-unspecified (IBD-U); 50.2% were female; median age was 42 years (IQR 56-32) and 43.9% were non-smokers. Only 994 people had steroid exposure (18.3%). In those exposed, median oral steroid daily dose was 0.22 mg (IQR 3.2-6.8); median oral steroid total dose was 246.1mg (IQR 351.2-69.2), and median annualized total steroid dose was 18.6 mg (IQR 31.6-13.3). Up to 10 courses of steroids were prescribed per person. IBD diagnosis, age, previous IBD surgery, stoma surgery, IBD therapy and age at disease onset reached statistical significance. Compared to people with UC, those with CD had less likelihood of both recent steroid exposure and prolonged exposure (OR 0.78, P=0.014 & OR 0.72, P=0.018 respectively). Adults between 20-29 years had a much higher likelihood of both recent and prolonged exposure compared to people > 70 years (OR 6.67, P=0.000 & OR 6.58, P=0.000 respectively). People on advanced therapies had a greater chance of both recent and prolonged exposure compared to people on 5-ASA alone (OR 1.65, P=0.05 & OR 1.71, P=0.000). Age at diagnosis reached statistical significance for steroid use parameters (OR 1.03, P=0.000), but with only modest effect size. Conclusion In this large real-world cohort, the majority had no recent steroid exposure. In those exposed, younger people, those with UC, and those with more active disease had higher likelihood of prolonged exposure. This suggests that steroid use may be further reduced by proactive tailoring of effective therapies for those with UC and focusing on disease control in younger people with IBD.

Abstract Background Inflammatory bowel disease (IBD) is a global health issue with Australia (AUS) and New Zealand (NZ) having amongst the highest prevalence rates worldwide. Our study examined the quality, safety, and consistency of care amongst ten Australasian centres. Methods Crohn’s Colitis Care (CCCare) is a cloud-based IBD-specific electronic medical record (EMR) used in Australasia. Deidentified data prospectively entered by clinicians and consumers during routine clinical practice were retrospectively analysed. Key performance indicators (KPI) were compared across two time periods, baseline (1st October 2021 to 30thSeptember 2022) and follow up periods (1st October 2023 to 30th September 2024). Centres with over 100 people with IBD with an assessment during the last 14-month period were included. Results At the end of the follow up period, 6794 people with IBD were included, 55.8% (n=3790) with Crohn’s Disease, 41.3% (n=2808) with Ulcerative Colitis and 2.9% (n=196) with IBD-Unclassified. There was an even gender distribution with 49.0% (n=3329) male, 48.2% (n=3276) female and 2.8% (n=189) did not have gender documented. The median age was 42 years (IQR 32 – 57) with a median disease duration of 11.3 years (IQR 5.6 – 19.7). The majority of people resided in AUS (71.2%, n=4834) and 28.8% (n=1960) in NZ. Across the two study periods, the proportion of people receiving an advanced therapy remained stable (53.2% vs 52.9%, p=0.76), however the number of people on dose escalated (DE) therapy increased (25.1% vs 28.5%, p < 0.001). In parallel, steroid use decreased; 12.4% vs 10.5%, p < 0.01. There was a reduction in the rate of hospital admissions (4.1% vs 2.6%, < 0.001) and surgeries (3.6% vs 1.6%, p < 0.001). There were no differences in the rates of endoscopic (53.1% vs 54.7%, p=0.34) and radiologic remission (41.0% vs 43.0%, p=0.49). There was a significant reduction in the completion of healthcare maintenance across all sites with a fall in overall covid vaccination (36.9% vs 29.8%, p<0.001), influenza vaccination (20.1% vs 5.0%, p<0.001) and skin care checks (12.0% vs 4.0%, p<0.001). There was no significant difference in the proportion of people currently smoking (10.5% vs10.9%, p=0.54). Conclusion Observed clinical improvements, including reduced steroid use, admissions, and surgeries, coincided with increased DE therapy, reflecting a shift toward tailored healthcare. Post-pandemic reduction in healthcare maintenance likely reflects provider and consumer fatigue. Implementing a value-based IBD management approach with continuous KPI monitoring via digital tools like CCCare is essential for optimizing outcomes, highlighting trends, and identifying areas for improvement in healthcare delivery.

Abstract Background On standard dosing of infliximab (IFX), one third of patients will develop secondary loss of response (LOR) by the first year and up to 50% of initial responders will develop LOR by 5 years.1 Sustained high trough levels and dose escalation are proven to increase the durability of infliximab.2 The role of proactive therapeutic drug monitoring (TDM) to guide this remains controversial. In 2019, our unit opted for proactive TDM (at week 6, week 14 and 6 monthly thereafter) as standard therapy to guide dose escalation in maintenance. We report the outcomes of our patient cohort over 2 years from initiation of IFX. Methods A retrospective chart review was performed between 01/01/2019 to 31/12/2021. All patients with IBD who received IFX were included. Patients with acute severe colitis were excluded as treatment protocol was different. Data on demographics, disease characteristics, immunomodifier, IFX dosing, frequency, drug and antibody levels were collected and analysed. Primary outcome was switching to different biologic as a marker of treatment failure. Standard IFX dosing is 5mg/kg IVI at 0, 2, 6 weeks for induction and 8 weekly in maintenance. The dose was escalated if week 6<15µg/mL, week 14/maintenance <5µg/mL, or <10µg/mL in stricturing/fistulising disease. Results 98 patients (58% male) were identified, 82% had Crohn’s disease (CD) and 18% Ulcerative Colitis (UC). Median age at diagnosis was 11 years old, and 12.5 years old at starting IFX. 81% received an immune modifier of which 64% had methotrexate and 39% azathioprine. 13% received escalated induction and 77% received escalated maintenance. The median week 6 level of standard vs escalated maintenance group was 22.8µg/mL vs 12.4µg/mL (p=0.01). 3% did not respond to induction and were discontinued. 2% developed IFX antibodies. At 1 year, 5% of CD and 22% of UC patients switched to a different biologic and at 2 years this was 13% and 44% respectively. Median time to switch was 53 weeks. Switching to alternate biologic was associated with escalated induction OR 5.2 (p<0.01) UC phenotype OR 5.6 (p<0.01) and concomitant steroid use OR 5.2 (p<0.04). Conclusion Our week 6 IFX level guided clinician decision to escalate dosing in maintenance. The outcomes for our cohort show good treatment durability particularly in CD, 95% at 1 year and 87% at 2 years, which is better than what has been reported.2 Patients with severe phenotype remain poor responders and difficult to treat as evident by receiving escalated induction, i.e escalation without TDM, and steroid use being predictors. This study adds to the growing body of evidence of the role of proactive TDM in increasing durability of IFX. References 1.Ding, N. S., Hart, A., & De Cruz, P. (2016). Systematic review: predicting and optimising response to anti-TNF therapy in Crohn's disease - algorithm for practical management. Alimentary pharmacology & therapeutics, 43(1), 30–51. https://doi.org/10.1111/apt.13445 2.Vahabnezhad, E., Rabizadeh, S., & Dubinsky, M. C. (2014). A 10-year, single tertiary care center experience on the durability of infliximab in pediatric inflammatory bowel disease. Inflammatory bowel diseases, 20(4), 606–613. https://doi.org/10.1097/MIB.0000000000000003

Abstract Background Inflammatory Bowel Disease (IBD) activity as well as disease monitoring and management have a substantial impact on the health-related quality of life (HRQoL) of affected patients1. This study investigated the association between HRQoL and gut microbial composition in IBD patients using the 32-item Inflammatory Bowel Disease Questionnaire (IBDQ-32). Methods Paired faecal and oral samples alongside participant demographics, disease characteristics and the IBDQ-32 survey were collected at baseline from patients with Crohn’s disease (CD) or ulcerative colitis (UC) enrolled in the Australian IBD Microbiome (AIM) study2 from June 2019 to November 2023. IBDQ-32 scores range from 32 to 224, with a higher score indicating better HRQoL. Patients were divided into two groups: impaired HRQoL (cumulative score <170) and preserved HRQoL (>170). Faecal and oral samples were self-collected in DNA stabilising buffer, aliquoted and stored at -80oC until extraction. Samples underwent 16S rRNA sequencing with annotation of DNA sequences to operational taxonomic units at the genus level. Differences in alpha diversity (Chao1) between groups were assessed using Mann-Whitney U tests. Linear discriminant analysis was performed between groups to identify significantly enriched bacterial taxa. Beta diversity (weighted UniFrac dissimilarity) in bacterial communities were shown using Principal Coordinate Analysis (PCoA), and significance of variance was tested using ADONIS in R. Results 446 participants (232 CD, 214 UC) returned baseline faecal (n = 403) and/or oral samples (n = 436) and were included in the analysis, with patient and HRQoL characteristics in Table 1. Most CD and UC patients were in clinical remission at baseline (77.4% and 65.2% respectively, Table 1). Despite this, impaired HRQoL was common in both CD (42%) and UC (41%). Patients with impaired HRQoL had lower faecal microbial alpha and beta diversity (Fig 1A,B). There were no differences in alpha or beta diversity in oral samples. Linear discriminant analysis showed 9 and 36 significantly altered genera enrichment in impaired and preserved HRQoL faecal samples respectively (Fig 1C). Conclusion Despite a high proportion of clinical and biochemical remission, impaired HRQoL was common amongst UC and CD patients within the AIM study. Lower faecal but not oral alpha diversity was associated with impaired HRQoL, indicating reduced microbial richness in the gut. A high number of bacterial taxa had differential enrichment according to HRQoL status. Identification of a distinct microbial signature associated with impaired HRQoL may help to identify patients that require both optimisation of disease control and greater psychosocial support. References 1.Little RD, Jayawardana T, Koentgen S, et al. Pathogenesis and precision medicine for predicting response in inflammatory bowel disease: advances and future directions. eGastroenterology 2024;2:e100006. doi:10.1136/ egastro-2023-100006 2.Williams A, Paramsothy R, Wu N, et al. Australia IBD Microbiome (AIM) Study: protocol for a multicentre longitudinal prospective cohort study. BMJ Open 2021;11:e042493. doi: 10.1136/bmjopen-2020-042493

We calculate the valence quark generalized parton distributions (GPDs) of the lightest pseudoscalar meson, pion, in an isospin asymmetric nuclear matter at zero temperature by employing a light-cone quark model. The medium modifications in the unpolarized GPDs have been incorporated by taking inputs from the chiral SU(3) quark mean field model. The electromagnetic form factors (EMFFs) and charge radii have been calculated for both the vacuum and in-medium cases. These results are found to be in agreement with the available experimental data and other model predictions.

We calculate the leading twist valence quark transverse momentum parton distribution functions (TMDs) and generalized parton distributions (GPDs) of the charged kaons in an isospin symmetric nuclear matter at zero temperature by employing the light-cone quark model. The medium modifications of the unpolarized TMDs and GPDs have been carried out by taking inputs from the chiral SU(3) quark mean field model. The electromagnetic form factors (EMFFs) and charge radii have been calculated from the unpolarized GPDs for both the vacuum and in-medium cases. We have also calculated the variation of average transverse and longitudinal momenta for the active quark at high baryonic density. These results are found to be in good agreement with the available experimental data as well as with other model predictions.

We present the valence quark distributions of the kaons in an isospin asymmetric dense strange medium consisting of nucleons and hyperons. The comparative analysis of in-medium parton distribution functions, electromagnetic form factors, and charge densities with respect to the free space distributions is studied in the light-cone quark model. The medium effects are incorporated in these distribution functions by using the effective quark masses, computed from the chiral SU(3) quark mean field model for finite values of baryon density, isospin asymmetry, and strangeness fraction parameters. We observe a suppression of the kaon electromagnetic form factors and a redistribution of charge density in high-density strange matter.