Influence of defects on the linear and nonlinear optical properties of Cu-doped rutile TiO2 microflowers.

Defects and disorder work as controlling parameters to alter the electronic structure of nanostructures and significantly influence their electronic, magnetic, and nonlinear optical (NLO) properties. In this study, we found that defect engineering is an effective strategy for tailoring the linear and nonlinear optical properties of Cu-doped titanium oxide (TiO2) flower-shaped nanostructures. The concentration of chemical doping of Cu in the TiO2 lattice creates intermediate defect states that impact electronic bandgap reduction and tunable defect luminescence. The estimation of the bandgap from density functional theory calculation follows the same trend of bandgap narrowing with Cu doping. The XPS study reveals that oxygen defects are responsible for bandgap narrowing and quenching of the PL intensity. A single-beam Z-scan technique with open and closed aperture configurations using ultrashort pulses centered at 532 nm excitation wavelength was used to study the NLO measurements. The open aperture reveals saturable absorption, whereas the closed aperture shows self-focusing behavior. The nonlinear absorption coefficient and refractive index extracted from NLO measurements demonstrate the linear dependence on the defect concentration and bandgap. The effects of heterogeneous dopants and lattice disorder on the nonlinear absorption behavior of these nanostructures are discussed in comparison with the figure of merit, non-linear refractive index, and absorption coefficient. The tunable NLO properties achieved by controlling such dopant-induced defects boost the scope of these nanostructures as optical limiting, optical switching, and optical photodiode applications.

Plasmon mediated SERS and photocatalysis enhancement in Au nanoparticle decorated 2D-TiSe2.

The combination of 2D materials and noble metallic nanostructure is becoming an attractive research domain for label-free, highly sensitive surface-enhanced Raman spectroscopy (SERS) applications. This study demonstrated photocatalysis degradation and SERS enhancements of organic fluorophore (Rhodamine 6G) on two-dimensional (2D) TiSe2using Raman spectroscopy. The Au nanoparticles (NPs) were decorated on TiSe2thin films by thermal annealing at variable temperatures. The selective deposition of Au NPs on the hexagonal TiSe2nanocrystals increases surface roughness, creating a larger surface area for molecule adsorption. It has been observed that the Au decoration at 250 °C on TiSe2exhibits efficient detection capabilities for R6G with the Raman intensity enhancement factors of the order of ≈105along with the significantly improved visible light-induced photodegradation efficiency. The optimized Au NP size creates large electromagnetic hot spots produced by strong plasmon coupling that assists in the charge transfer mechanism among TiSe2, Au NPs, and R6G for enhanced SERS and photocatalysis activities. It has been observed that the intensity of Raman scattering decreases as the Au NP size increases on the TiSe2material. A possible charge transfer mechanism is proposed with an energy band diagram. The simultaneous measurement of SERS and photocatalytic dye degradation in Au decorated TiSe2can be used as a sensitive technique for water pollution treatment and biodegradable organic contaminants for the environmental ecosystem.

Cathodoluminescence and optical absorption spectroscopy of plasmonic modes in chromium micro-rods.

Manipulating light at the sub-wavelength level is a crucial feature of surface plasmon resonance (SPR) properties for a wide range of nanostructures. Noble metals like Au and Ag are most commonly used as SPR materials. Significant attention is being devoted to identify and develop non-noble metal plasmonic materials whose optical properties can be reconfigured for plasmonic response by structural phase changes. Chromium (Cr) which supports plasmon resonance, is a transition metal with shiny finished, highly non-corrosive, and bio-compatible alloys, making it an alternative plasmonic material. We have synthesized Cr micro-rods from a bi-layer of Cr/Au thin films, which evolves from face centered cubic to hexagonal close packed (HCP) phase by thermal activation in a forming gas ambient. We employed optical absorption spectroscopy and cathodoluminescence (CL) imaging spectroscopy to observe the plasmonic modes from the Cr micro-rod. The origin of three emission bands that spread over the UV-Vis-IR energy range is established theoretically by considering the critical points of the second-order derivative of the macroscopic dielectric function obtained from density functional theory (DFT) matches with interband/intraband transition of electrons observed in density of states versus energy graph. The experimentally observed CL emission peaks closely match thes-dandd-dband transition obtained from DFT calculations. Our findings on plasmonic modes in Cr(HCP) phase can expand the range of plasmonic material beyond noble metal with tunable plasmonic emissions for plasmonic-based optical technology.

Temperature-dependent excitonic emission characteristics of lead-free inorganic double perovskites and their third-order optical nonlinearities.

We report temperature-dependent photoluminescence (PL) in the temperature range between 77 K and 300 K, and room temperature nonlinear optical (NLO) properties of solution processed lead-free Cs2NaBiI6 (CNBI) and Cs2KBiI6 (CKBI) perovskite films. The de-convolution analysis of temperature-dependent PL spectra showed thermal quenching behavior of free-exciton (FX) emission, an unusual blue-shift of PL emission, and line broadening with increasing temperature as a consequence of strong exciton-phonon interaction. The nonlinear refractive index (n2) and nonlinear absorption coefficient (ß) of both the CNBI and CKBI films are determined using a closed aperture (CA) and open aperture (OA) Z-scan technique, respectively. Both the CNBI and CKBI perovskites exhibited features of saturable absorption (SA) with ß âˆ¼ -6.23 × 10-12 cm W-1, and -1.14× 10-12 cm W-1, respectively. The CA measurements depicted a self-defocusing effect in both the samples with n2 values ∼-1.06 × 10-14 cm2 W-1 and -1.337× 10-14 cm2 W-1, respectively. With such emission and NLO characteristics, CNBI and CKBI perovskite films can be used for designing eco-friendly optoelectronic and NLO devices.

Modulation of intrinsic defects in vertically grown ZnO nanorods by ion implantation.

Intrinsic defects created by chemically inert gas (Xe) ion implantation in vertically grown ZnO nanorods are studied by optical and X-ray absorption spectroscopy (XAS). The surface defects produced due to dynamic sputtering by ion beams control the fraction of O and Zn with ion fluence, which helps in tuning the optoelectronic properties. The forbidden Raman modes related to Zn interstitials and oxygen vacancies are observed because of the weak Fröhlich interaction, which arises due to disruption of the long-range lattice order. The evolution of the lattice disorder is identified by O K-edge and Zn K-edge scans of XAS. The hybridization strength between the O 2p and Zn 4p states increases with ion fluence and modulates the impact of intrinsic defects. The ion irradiation induced defects also construct intermediate defects bands which reduce the optical bandgap. Density functional theory (DFT) calculations are used to correlate the experimentally observed trend of bandgap narrowing with the origin of electronic states related to Zn interstitial and O vacancy defects within the forbidden energy gap in ZnO. Our finding can be beneficial to achieve enhanced conductivity in ZnO by accurately varying the intrinsic defects through ion irradiation, which may work as a tuning knob to control the optoelectronic properties of the system.

Phase evolution in thermally annealed Ni/Bi multilayers studied by X-ray absorption spectroscopy.

The thin films of Ni and Bi are known to form NiBi3 and NiBi compounds spontaneously at the interface, which become superconducting below 4.2 K and show ferromagnetism either intrinsically or due to Ni impurities. Formation of NiBi3 and NiBi is a slow diffusion reaction, which means the local environment around Ni and Bi atoms may vary with time and temperature. In this report, we assess the feasibility of using X-ray Absorption Spectroscopy (XAS) as a tool to track the changes in local bonding environment in NiBi3 and NiBi. Thermal annealing at temperatures up to 500 °C was used to induce changes in the local environment in NiBi3 system. Consequent decomposition of NiBi3 into NiO and Bi has been tracked through changes in structural and magnetization behavior, which matched well with the findings of XAS. In addition, the magnetic hysteresis measurements indicated that NiO should be the dominant phase when NiBi3 is annealed at 500 °C. This was corroborated from XAS and was found to be >90%. The shift in K-edge of Ni in annealed samples was attributed to increasing charge state on Ni atom, which was ascertained by Bader charge analysis using Density Functional Theory (DFT). This study correlating macroscopic properties of NiBi3 with local bonding environment of the system indicates that XAS can be a very reliable tool for studying dynamics of diffusion in the NiBi3 system.

Excitonic properties of layer-by-layer CVD grown ZnO hexagonal microdisks.

We have investigated the excitonic properties of highly crystalline ZnO hexagonal microdisks grown by the chemical vapour deposition technique. It was observed that a suitable negative catalyst like chlorine suppresses the crystal growth along the (0001) direction. We propose a qualitative model for the experimentally observed layer-by-layer growth mechanism of the microdisks. Room temperature photoluminescence of the microdisks manifests a very high near-band-edge (NBE) emission peak in the UV region and a minor defect peak in the visible region. The excitonic emission of the microdisks was studied using the low-temperature photoluminescence down to 83 K, which reveals a surface exciton peak in the NBE region and well fitted higher-order phonon replicas.

Ectopic salivary gland found on rectal biopsy-a rare pathological diagnosis.

BACKGROUND: Heterotopic tissue can be found throughout the GI tract, most commonly being gastric tissue. The finding of ectopic salivary tissue located in the GI tract is an exceedingly rare finding. We present a case of an otherwise healthy 30-year-old male with rectal bleeding who underwent biopsy of a submucosal rectal lesion with pathologic findings of ectopic salivary gland tissue. CASE PRESENTATION: Our patient is a 30-year-old male who presented with rectal bleeding. During his workup, he underwent colonoscopy and subsequent endoscopic ultrasound after discovery of a submucosal mass in the rectum measuring approximately 2 × 1 cm. Biopsies were sent which returned showing ectopic salivary gland tissue superimposed on hyperplastic rectal mucosa. The patient's symptoms resolved and he has not had recurrence of bleeding. CONCLUSIONS: Ectopic salivary gland tissue is a rare pathological finding in the rectum. It can present as a symptomatic lesion or be found incidentally. There is no clear reason for its presence, but it is felt to be due to metaplasia, developmental anomalies, or idiopathic in nature. Treatment includes excision and monitoring.

Clinico-radiological Profile of Posterior Reversible Encephalopathy Syndrome and Its Associated Risk Factors in PICU: A Single-center Experience from a Tertiary Care Hospital in Bhubaneswar, Odisha.

OBJECTIVE: Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiographic entity of heterogeneous etiologies having similar clinical and neuroimaging features. Pediatric data are sparse, making early diagnosis challenging, which needs a high index of suspicion. So, we conducted this study to evaluate clinico-radiological features, associated risk factors, etiology, and outcome in children. MATERIALS AND METHODS: This is a retrospective case series of patients, diagnosed as having PRES and followed up at a tertiary care hospital in Eastern India between September 2016 and December 2019. RESULTS: Among 16 patients with a median age of 9.5 years [interquartile range (IQR) 8-13.75] and a male preponderance (75%), common underlying diseases were post-streptococcal glomerulonephritis (56.3%) and renovascular hypertension (12.5%). Acute elevation of blood pressure was found in all patients (n = 16). The neurological symptom was seizure (87.5%), mental changes (68.75%), headache (43.8%), vomiting (31.3%), and visual disturbances (31.3%). The most common triggering factor was hypertension (100%), use of mycophenolate mofetil and prednisolone (12.5%), and hemodialysis (12.5%). Anemia was present in 15 (93.4%) patients at the time of admission. All showed abnormal neuroimaging with 55% having atypical involvement. The most common site was the parietal-occipital cortex (88%), frontal and temporal lobe (44% cases each), and the cerebellum (13%). Clinical recovery was followed by a radiological resolution in all survived except in one, who developed visual impairment. CONCLUSION: Posterior reversible encephalopathy syndrome should be considered in the differential diagnosis of patients who present with acute neurological disturbances and underlying diseases such as renal disorders, vasculitis, malignancy, and use of immunosuppressant accompanied by hypertension. Early diagnosis and treatment of comorbid conditions are of paramount importance for the early reversal of the syndrome. HOW TO CITE THIS ARTICLE: Behera CK, Jain MK, Mishra R, Jena PK, Dash SK, Sahoo RK. Clinico-radiological Profile of Posterior Reversible Encephalopathy Syndrome and Its Associated Risk Factors in PICU: A Single-center Experience from a Tertiary Care Hospital in Bhubaneswar, Odisha. Indian J Crit Care Med 2020;24(12):1223-1229.

Self-assembled nano-dots structures on Si(111) surfaces by oblique angle sputter-deposition.

Controlled surface modification and nano-dots structures over Si(111) surfaces have been produced by oblique angle sputter deposition of 80 keV Ar+ beam. Temporal parameters such as self-assemble, tunability of size and density of fabricated nano-dots exhibit distinct fluence dependence. Crystalline to amorphous (c/a) phase transition for sputter deposited Si(111) surfaces has been observed. RBS/C reveals the non-linear response of damage distribution with Ar ion fluence. Compositional alterations like degree of amorphization, damage distribution and depth profiling of Ar in these nano-structured surfaces has been correlated with the morphological and structural findings. The underlying self-organization mechanism relies in ion beam sputtering induced erosion and re-deposition of Si atoms thereby leading to mass transport inside the amorphous layers. Such nano-structured Si(111) surfaces could be applied as key engineering substrates for surface reconstruction, optoelectronic devices, data storage devices, recording media and photovoltaic applications.

Influence of Anion Variations on Morphological, Spectral, and Physical Properties of the Propidium Luminophore.

Propidium iodide (3,8-diamino-5-[3-(diethylmethylammonio)propyl]-6-phenylphenanthridinium diiodide, [P][I]), is a well-known red fluorescent dye that is widely used for biological applications such as staining. In this study, we have replaced the iodide counteranion of [P][I] with three hydrophobic and bulky organic anions, trifluoromethanesulfonate/[TfO], bis(trifluoromethanesulfonyl)imide/[NTf2], and bis(perfluoroethylsulfonyl)imide/[BETI], and have thus obtained a propidium-derived group of uniform materials based on organic salts (PGUMBOS). The morphological, spectral, and physical properties of these materials were investigated in order to understand the impact of anion variations. While [P][I] is a crystalline solid, propidium salts with [BETI] or [NTf2] counteranions, i.e., [P][BETI] and [P][NTf2], have significantly lower crystallinity as reflected in powder X-ray diffraction data. In addition, [P][BETI] and [P][NTf2] exhibited improved photothermal stability as compared to [P][I] when examined using thermogravimetric analysis and time-dependent kinetic fluorescence experiments under the given experimental conditions. Spectral and electronic properties of the propidium luminophore were not significantly changed upon anion variations, although fluorescence lifetimes and quantum yields showed a systematic increase with decreasing solvent polarity. The experimental HOMO-LUMO energy gaps of these compounds were ∼2 eV with energies of HOMO and LUMO orbitals obtained as -5.15 (±0.08) and -3.19 (±0.08) eV.

Reliability of 18F-FDG PET Metabolic Parameters Derived Using Simultaneous PET/MRI and Correlation With Prognostic Factors of Invasive Ductal Carcinoma: A Feasibility Study.

OBJECTIVE: The objective of our study was to correlate semiquantitative PET parameters-standardized uptake value (SUV) and total lesion glycolysis (TLG)-derived in simultaneous PET/MRI using MRI-based attenuation correction with clinical and histopathologic prognostic factors in patients with breast cancer. MATERIALS AND METHODS: Eighty-two invasive ductal carcinomas in 69 women were included in the study. All the subjects underwent whole-body (WB) PET/MRI (supine WB mode) and dedicated PET/MRI of the breast (prone breast imaging mode) for staging on a simultaneous PET/MRI system. The SUV and TLG values were calculated from 18F-FDG PET data using MRI-based attenuation correction (2-point Dixon sequence for tissue segmentation). Relationships between SUV and TLG values and clinical and histopathologic parameters (i.e., tumor size, tumor grade, Ki-67 status, and hormonal receptor expression status) were evaluated using Spearman correlation coefficient analysis. RESULTS: A significant correlation was observed between mean SUV (SUVmean) and maximum SUV (SUVmax) values derived with WB PET and regional PET of the breasts performed simultaneously with MRI (r = 0.88 and 0.89, respectively). A significant difference (p < 0.05) was observed in SUVmean, SUVmax, and TLG values between the grades and molecular subtypes of breast cancer. High SUVmean, SUVmax, and TLG values were found to correlate with larger tumor size (p < 0.01), higher proliferation index (p < 0.05), higher grade (p < 0.01), and triple-negative hormonal receptor status (p < 0.01, p < 0.05). CONCLUSION: Semiquantitative FDG parameters derived with MRI-based attenuation correction in simultaneous PET/MRI are reliable and correlate with clinicopathologic features such as grade as well as subtype and thus could be used in the prognostication of breast cancer.

Suppression of near band edge emission in specially engineered ZnO twin nanorods.

We report the synthesis of a unique zinc oxide nanorod structure in which an amorphous ZnO layer is sandwiched between two identical crystalline segments of ZnO. A simple hydrothermal reaction method was used for this purpose, which allowed us to tune the amorphous and crystalline sections of the nanorods via reaction temperature. A systematic study of the morphology and dimensions of the nanorods grown under various conditions was performed using a combination of scanning and transmission electron microscopy. Transmission electron microscopy (TEM) clearly showed an amorphous separation between the two crystalline segments. UV-vis absorption spectroscopy of the twin nanorods (TNRs) showed a redshift in the optical band gap as a function of the growth duration, indicating slightly stressed growth of the crystalline segments. For a longer growth duration, as the amorphous gap starts to get bridged by crystalline growth, redshift in optical band gap becomes constant. This confirms a true mechanical gap between the two crystalline segments of the nanorods. Temperature dependent photoluminescence (PL) spectra of the TNRs showed a variation in free exciton (FX) emission energy, which fitted very well to a model incorporating lattice dilation in addition to the standard electron-phonon interactions. At low temperatures (below ∼180 K) we observed the appearance of visible emission peaks due to localization of defect levels. A loss in the near band edge emission intensity was observed at low temperatures, commensurate with the appearance of defect emission in the visible range.

Nanoscale interface engineering in ZnO twin nanorods for proposed phonon tunnel devices.

Zinc oxide twin nanorods, with two identical crystalline sections connected by an amorphous layer, were reproducibly grown using a simple one-step hydrothermal technique. The thickness of the amorphous layer between the crystalline segments was tunable with growth parameters, as confirmed by high resolution transmission electron microscopy. The photoluminescence spectra of these twin nanorods exhibit strong near band edge emission in the UV range, with convoluted phonon sidebands. De-convolution analyses of these spectra showed that the amorphous interlayers act as effective phonon barriers beyond a certain thickness. Such oriented grown individual crystalline-amorphous-crystalline structures may be a suitable test system for fundamental studies of phonon tunneling in the nanostructure. While physical vapor deposition techniques are seriously constrained in realizing crystalline-amorphous-crystalline structures, our results show the viability of engineering embedded interfaces via chemical routes.

A radiological parametric comparison of low-grade lytic spondylolisthesis to degenerative spondylolisthesis - A retrospective approach to establish its dysplastic origin.

Objectives: This study aims to compare low-grade lytic spondylolisthesis (LS) and degenerative spondylolisthesis (DS) radiologically. In addition, it seeks to identify underlying similarities between LS and DS. Methods: This study included patients with low-grade single-level spondylolisthesis at L4-L5 or L5-S1. They were categorized into LS and DS. Radiological features, including pedicle height, width, transverse, and sagittal angle, as well as anterior vertebral heights (AVH) and posterior vertebral heights (PVH), were measured using T1-weighted magnetic resonance imaging. Results: The study involved 88 patients: 46 in the DS group and 42 in the LS group. In the LS group, the AVH was significantly higher than the posterior height at L4 and L5 (L4 PVH/AVH ratio 0.93 in LS vs. 0.96 in DS; L5 PVH/AVH ratio 0.84 in LS vs. 0.92 in DS), and pedicles were more medially oriented (L4: 19.62° in LS vs. 17.7° in DS; L5: 28.92° in LS vs. 26.47° in DS). In addition, at L5, the pedicle height (10.67 mm in LS vs. 11.48 mm in DS) and width (13.56 mm in LS vs. 14.37 mm in DS) were smaller compared to the DS group. Conclusions: Low-grade LS shows distinct radiological vertebral and pedicle anatomy compared to DS. Short and thin pedicles and wedge-shaped vertebrae in LS resemble DS, indicating its dysplastic origin.

Effect of phonon anharmonicity on thermal conductivity of ZnTe Thin films.

The ZnTe thin film is a potential material for optoelectronic devices in extreme temperature and radiation environments. In this report, the thermal conductivity of ZnTe films is measured non-invasively using the micro-Raman method and correlated with the phonon anharmonic effect. The evolution of crystalline ZnTe thin films from Te/ZnO bilayer by thermal annealing at 450 ∘C has been observed above the melting point of Te, which is confirmed from x-ray diffraction and high-resolution transmission electron microscopy. The ZnTe thin films illustrate three longitudinal phonon modes with higher harmonics of nLO (n= 3) at room temperature. Temperature-dependent Raman spectra in the range of 93-303 K are used to analyze the phonon anharmonicity from Raman shift, FWHM, and Phonon lifetime of the thin films. The Balkanski model is used to fit the anharmonicity-induced phonon frequency shift of nLO modes as a function of temperature, taking into account three- and four-phonon interactions. The intensity ratio of the I2LO/I1LOand I3LO/I2LOprovide information about the electron-phonon coupling strength, which is influenced by the anharmonic effect. The laser power-dependent Raman spectra are used to determine the thermal conductivity of the ZnTe films, which is found to be approximately 9.68 Wm-1K-1, remains relatively constant for all nLO modes, indicating that multi-phonon scattering process. The correlation between thermal conductivity and phonon anharmonicity can pave the way for understanding the phonon scattering process in ZnTe thin films for high-performance optoelectronic device applications in harsh conditions.

A Case of Chronic Granulomatous Disease Masquerading As Tubercular Lymphadenitis in an Infant.

Chronic granulomatous disease (CGD) is a rare inborn error of immunity characterized by recurrent fungal and bacterial infections due to defective nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity. This case report describes an 11-month-old female who was initially diagnosed with tubercular lymphadenitis and presented with fever and bilateral neck swelling. Despite receiving anti-tubercular treatment (ATT) and intravenous antibiotics, the patient experienced recurrent infections and abscesses, prompting further investigation. Laboratory tests revealed normal immunoglobulin levels but abnormal nitroblue tetrazolium (NBT) and dihydrorhodamine (DHR) tests, indicating CGD. Genetic analysis (clinical exome by next-generation sequencing) confirmed a novel NCF2 gene mutation associated with autosomal recessive CGD. This patient was treated with prophylactic antibiotics and antifungals and subsequently underwent successful hematopoietic stem cell transplantation (HSCT). This highlights the diagnostic challenges associated with CGD, particularly in tuberculosis-endemic regions such as India, emphasizing the importance of considering primary immunodeficiency disorders in patients with recurrent infections. Early diagnosis and appropriate treatment, including HSCT, can significantly improve patient outcomes. The patient remained infection-free on prophylactic antimicrobials for 1.5 years post-discharge, demonstrating the potential for a favorable prognosis with timely intervention and comprehensive management.

Reaction Atmosphere-Controlled Thermal Conversion of Ferrocene to Hematite and Cementite Nanomaterials-Structural and Spectroscopic Investigations.

Recently, we have reported the influence of various reaction atmospheres on the solid-state reaction kinetics of ferrocene, where oxalic acid dihydrate was used as a coprecursor. In this light, present study discusses on the nature of decomposed materials of the solid-state reactions of ferrocene in O2, air, and N2 atmospheres. The ambient and oxidative atmospheres caused the decomposition to yield pure hematite nanomaterials, whereas cementite nanomaterials along with α-Fe were obtained in N2 atmosphere. The obtained materials were mostly agglomerated. Elemental composition of each material was estimated. Using the absorbance data, the energy band gap values were estimated and the related electronic transitions from the observed absorption spectra were explored. Urbach energy was calculated for hematite, which described the role of defects in the decomposed materials. The nanostructures exhibited photoluminescence due to self-trapped states linked to their optical characteristics. Raman spectroscopy of hematite detected seven Raman modes, confirming the rhombohedral structure, whereas the D and G bands were visible in the Raman spectra for cementite. Thus, the reaction atmosphere significantly influenced the thermal decomposition of ferrocene and controls the type of nanomaterials obtained. Plausible reactions of the undergoing solid-state decomposition have been proposed.

Utilization of Ayurveda, Yoga, Naturopathy, Unani, Siddha, and Homoeopathy (AYUSH) Practitioners' Services Among Older Adults: Results From the Longitudinal Aging Study in India.

BACKGROUND: Ayurveda, yoga, naturopathy, Unani, Siddha, and homeopathy (AYUSH) form an alternative system of medicine in India. Understanding the utilization of AYUSH practitioners' services is crucial to substantiating the current government initiatives to mainstream AYUSH in the Indian health system. The utilization of AYUSH practitioners' services among different sub-populations, including older adults, for various health conditions is underexplored. The present study explores the utilization of AYUSH practitioners' service among older Indian adults and its correlates. METHODS: During 2017-2018, the Longitudinal Aging Study in India (LASI) conducted a nationally representative study among adults aged 45 years or more and their spouses. The study leveraged this data from publicly available LASI. Descriptive analysis and cross-tabulation were performed using a subset of older adults (age ≥ 60 years, n = 31,464). The utilization of AYUSH practitioners' services was taken as the outcome variable. A logistic regression model was employed to understand the independent effect of various explorative variables on the use of AYUSH practitioners' services. RESULTS: One in 14 older adults utilized the services of AYUSH practitioners. The socio-demographic factors that were looked at, including religion, residence, and caste were significant independent factors for AYUSH consultation. Among chronic conditions, hypertension (use-5.6%, AOR: 1.24, CI: 1.09-1.40), diabetes (use-4.2%, AOR: 1.31, CI: 1.09-1.57), and arthritis (use-9.1%, AOR: 0.59, CI: 0.52-0.67) were independent determinants of AYUSH practitioners' service utilization. In the fully adjusted model, the effect of explanatory variables is almost similar to that in the minimally adjusted model. Only the effect of the female gender was accentuated in magnitude, whereas the effect of diabetes was partially attenuated. CONCLUSION: The preference for AYUSH practitioners' service among older adults is determined by the complex interplay between socio-demographic factors and disease conditions. Though utilization of AYUSH practitioners' service was high among certain underprivileged sections, it is assuring that education and income do not affect older populations' preference for AYUSH practitioners' service.