Modular electromagnetic railgun accelerator for high velocity impact studies.

A modular electromagnetic railgun accelerator facility named "RAFTAR" (i.e., Railgun Accelerator Facility for Technology and Research) has been commissioned and its performance has been characterized for high velocity impact testing on materials in a single-shot mode. In the first tests, RAFTAR demonstrated an acceleration of more than 1000 m/s for an 8 g solid aluminum-7075 armature projectile. The current fed was 220 kA, having a muzzle time of about 1.75 ms. It is a single pulse breech-fed rectangular bore (14 × 13 mm2) railgun, and its 1.15 m long barrel assembly consists of two parallel copper bars with an inter-gap of 13 mm that are encased within 50 mm thick high strength reinforced fiberglass sheets (Garolite G10-FR4) and bolted from both the sides. RAFTAR is powered by two capacitor bank modules that have a maximum stored energy of 160 kJ each (containing eight 178 µF/15 kV capacitors), two high power ignitron switches, and a pulse shaping inductor. To obtain consistent acceleration of the armature inside the barrel, reversal of driving current is prevented, and its pulse duration is stretched by tactical integration of the crowbar switch and bitter coil inductor in the circuit. Armature projectile velocity measurement in-bore and outside in free space was performed by the time-of-flight technique using indigenously made miniature B-dot sensors and a novel shorting-foil arrangement, respectively. The time resolved measurement of the in-bore armature evidenced a velocity-skin-effect in the high acceleration phase. There is good agreement between the experimentally measured and theoretically predicted efficiency, confirming the optimal choice of operating parameters. The conclusion summarizes important experimental findings and analyzes the underlying causes that limit the performance of railguns.

Correlation of Clinical, Hormonal, Biochemical and Ultrasound Parameters Between Adult and Adolescent Polycystic Ovarian Syndrome: Adult and Adolescent PCOS.

Purpose: To correlate the clinical, hormonal, biochemical and ultrasound parameters in adolescent patients with polycystic ovarian syndrome (PCOS) and to compare them with adult patients. Methods: This was a prospective, correlational study. 50 adult (20-35 years) and 50 adolescent patients (15-19 years) who had features of PCOS (Rotterdam Criteria, 2003) were selected. The control group comprised of 50 women of same age in each group with normal parameters. Pelvic ultrasound was done in early follicular phase (3-5th day of menstrual cycle). Assessment of hormonal and biochemical parameters (LH/FSH ratio, free testosterone level, lipid profile and fasting glucose/insulin ratio) and grey-scale ultrasound was done. Results: No significant difference was observed in menstrual pattern in adults and adolescents with PCOS. The mean values of serum LH/FSH ratio and free testosterone were significantly higher in both adult and adolescent PCOS patients as compared to their controls (p < 0.001). The mean value of serum insulin was significantly higher (p < 0.001) with positive correlation (adult: r = 0.655, p < 0.01; adolescent: r = 0.451, p < 0.01) of serum insulin with free testosterone. Hyperandrogenemia without hyperinsulinemia was found in 56% adolescent and 60% adult PCOS patients. 82% adolescent and 88% adult PCOS patients showed multiple follicles (> 5) on ultrasound. The ovarian morphology had positive correlation with serum LH and free testosterone. The mean ovarian volume was significantly higher in adult (10.48 ± 4.38 vs. 4.17 ± 0.91) and adolescent (11.08 ± 5.82 vs. 4.23 ± 0.89) PCOS patients, when compared with controls, respectively. Conclusion: No statistically significant difference was noted in PCOS between adults and adolescents.

A quest for cytocompatible metal organic frameworks in non-viral gene therapy: Relevance of zeolitic imidazolate framework-8.

Metal-organic frameworks (MOFs) are an emerging group of nanomaterials for successful biomedical applications in gene therapy. The most commonly biocompatible MOFs are zinc-based ZIFs, zirconium-based UiOs, and iron-based MILs. However, despite increasing applications, a comparative study to underscore the critical factors for determining effective gene delivery by such MOFs is lacking. Herein, we evaluate the potential of UiO-66 and MIL-88B and ZIF-8 for gene therapeutics delivery; revealing the comparative importance of ZIF-8. Cytotoxicity assays proved insufficient for selecting the ideal gene delivery MOF vehicle. Synthesis conditions such as ability of the MOF scaffold to envelop the gene during in-situ synthesis, post-treatment such as washing, and gene loading efficiency proved to be the critical factors in determining the favourable MOF from the material selection perspective. Rapid in-situ synthesis under physiological conditions, successful gene loading, and low concentration requirements favour ZIF MOFs as gene delivery vehicles. Impact on cellular physiology, metabolism, and architecture revealed neutrality of the delivery system; and relative effects on pro-inflammatory and anti-inflammatory cytokines suggest immunomodulatory impact.

Expression and polymorphism of Follistatin (FST) gene and its association with growth traits in native and exotic chicken.

Follistatin (FST), a member of the transforming growth factor beta super-family regulates body growth by inhibiting the binding of myostatin (an inhibitor of growth) with its receptor in chicken. An experiment was conducted to explore ontogenic expression of the follistatin gene, determine polymorphism at the coding region of the gene and estimate its effect on growth traits in native (Aseel) and exotic broiler (PD-1) and layer (White Leghorn) chicken. The significant differences of FST gene expression were observed among the breeds revealing significantly (p < 0.05) higher expression in PD-1 line followed by White Leghorn and Aseel breeds during both embryonic and post-hatch period. The polymorphism at the functional domain of the FST gene was identified with the presence of 4 haplotypes. The follistatin haplogroups had the significant effect on body weights (p < 0.05) at 42 days of age in the White Leghorn, PD-1 and Aseel breeds (h1h1 in PD-1, h1h4 in White Leghorn and h1h2 haplogroups in Aseel breeds had the highest body weights of 770.04 ± 12.96, 246.28 ± 7.60 and 270.00 ± 10.68 g, respectively). It is concluded that the follistatin gene expressed differently during the embryonic and post-embryonic period across the breeds and the coding region of the gene was polymorphic having significant effects on growth traits in chicken.

Power Doppler sonography - A supplement to hysteroscopy in abnormal uterine bleeding: Redefining diagnostic strategies.

Background: Abnormal Uterine Bleeding (AUB) is a very frequent cause of gynecological visits in women of all age groups. Ultrasound pelvis with or without endometrial sampling have been conventionally used to make diagnosis. Power Doppler is a comparatively recent modality which can be used to screen patients who will need endometrial biopsy/ curretage. We hereby conducted a study to compare the diagnostic accuracy of power Doppler sonography and hysteroscopy with histopathology associated with abnormal uterine bleeding. We also calculated the incidence of uterine pathology in AUB by power Doppler ultrasound and hysteroscopy and compared it with histopathology. Methods: This prospective cohort study was conducted at the Department of Obstetrics and Gynaecology, Institute of Medical Sciences, Banaras Hindu University. After excluding 42 women, a total of 100 women fulfilling the inclusion criteria contributed to our study. Selected women underwent power Doppler ultrasound and hysteroscopy with guided biopsy. Results were compared with histopathology as per the gold standard. Evaluation of sensitivity, specificity, positive and negative predictive values were performed for each modality. All statistical analyses were performed using the SPSS 11.0 statistical package. P value ≤0.05 was considered statistically significant for all tests used. Results: Sensitivity and specificity of power Doppler are 75% and 100% for carcinoma endometrium, 72.72% and 98.9% for endometrial hyperplasia, and 81.81% and 100% for endometrial polyp, respectively. Conclusion: : Power Doppler sonography can be used to screen outpatients who do not need an endometrial biopsy for abnormal uterine bleeding. This will avoid unnecessary hysteroscopy in definitive benign cases, and watchful hysteroscopy in suspected premalignant and malignant cases. Irregular branching vessels and color splashes were found to be the best parameters for diagnosing endometrial carcinoma. Power Doppler should be done along with transvaginal sonography in all cases of abnormal uterine bleeding.

Computed Tomography-Based Interstitial Brachytherapy for Recurrent Cervical Carcinoma in the Vaginal Apex.

AIMS: To determine the factors influencing the outcomes of patients with recurrences post-hysterectomy for cervical cancers treated with external beam radiotherapy (EBRT) and interstitial brachytherapy. MATERIALS AND METHODS: This prospective study accrued 90 patients between October 2008 and May 2014. All patients had had a prior hysterectomy and were diagnosed with recurrent vaginal apex cancers with squamous cell carcinomas. All underwent EBRT of 50 Gy (2 Gy/fraction) using tomotherapy-based image-guided intensity-modulated radiotherapy with concurrent chemotherapy of weekly cisplatin (40 mg/m2) followed by high dose rate interstitial brachytherapy boost of 20 Gy (4 Gy/fraction twice a day). Local relapse, disease-free and overall survival were determined. RESULTS: At a median follow-up of 74 months (4-123 months), 10/90 (11%) patients had local failure as the first site of relapse and 12/90 (13.3%) had first distant relapse. Only one patient had synchronous local and distant relapse. The 7-year local relapse-free, disease-free and overall survival were 87.6, 68.3 and 68.3%, respectively. Grade 2 and 3 rectal toxicity were seen in 5.6 and 3.1% of patients, respectively. Among these, two (2.2%) patients underwent temporary diversion colostomy due to vaginal sigmoid and rectovaginal fistula. Grade 2 and 3 bladder toxicity were seen in 5.6 and 1.1% of patients, respectively. In summary, the lateral disease extent (P = 0.048) and the presence of nodal disease at diagnosis (P = 0.08) had a statistically significant or borderline impact on local relapse without any impact on disease-free survival. Tumour size in itself did not affect overall survival. CONCLUSION: With the integration of EBRT and interstitial brachytherapy, most vaginal apex recurrences can be salvaged. An excellent local control and survival is achievable using intensity-modulated radiotherapy with image guidance and concurrent chemotherapy followed by high dose rate interstitial brachytherapy.

Impact of neoadjuvant chemotherapy on thrombus viability in patients with Wilms tumour and caval extension: systematic review with meta-analysis.

BACKGROUND: Inferior vena cava (IVC) tumour thrombus in children with Wilms tumour is typically managed with neoadjuvant chemotherapy with the intention of achieving thrombus regression in order to minimize the risks associated with complex vascular surgery. METHODS: A systematic review of Medline and Embase databases was undertaken to identify all eligible studies with reference to thrombus viability in Wilms tumour index cases with caval/cardiac extension. A meta-analysis of proportions was utilized for pooled thrombus viability data across studies. Logistic regression was used to analyse the relationship between thrombus viability and duration of chemotherapy. RESULTS: Thirty-five eligible observational studies and case reports met inclusion criteria describing a total of 236 patients with thrombus viability data. The pooled proportion of patients with viable tumour thrombus after neoadjuvant chemotherapy was 0.53 (0.43-0.63). Logistic regression analysis of 54 patients receiving either a standard (4-6 weeks) or extended (more than 6 weeks) course of neoadjuvant chemotherapy resulted in an odds ratio of 3.14 (95 per cent c.i. 0.97 to 10.16), P = 0.056, with extended course therapy trending towards viable tumour thrombus. CONCLUSION: Preoperative chemotherapy is successful in achieving non-viability of caval and cardiac thrombi in around 50 per cent of children, without added benefit from extended cycles of neoadjuvant chemotherapy. Risks versus benefits of extirpative vascular surgery must be considered, therefore, for these high-risk patients.

Quality evaluation of near-isogenic line of the wheat variety HD2733 carrying the Lr24/Sr24 genomic region.

A near-isogenic line (NIL) of the Indian wheat variety HD2733, carrying an introgressed Lr24/Sr24 genomic region was used for studying the effect of this introgression on quality traits. Data on the grain yield and 21 quality traits were recorded in this NIL and its recurrent parent (RP), both of which were grown in a randomized block design for two consecutive years. The statistical analysis revealed that grain yield was on par between the NIL and the RP. The NIL and its RP were both hard grained but the NIL showed a grain hardness index reduced by 9.7%. However, quality traits such as grain weight, protein content, sedimentation value, gluten traits, and solvent retention capacity were significantly higher in the NIL. The NIL also showed an increase in dough stability, a lower degree of softening and a higher farinograph quality number. These results indicated that the NIL could be utilized for hard grain, high protein and strong gluten-based products. An overall improvement in the quality of the NIL over its recurrent parent and without any yield penalty suggests that the Lr24/Sr24 genomic region could be gainfully utilized in wheat breeding for improving the industrial quality of wheat without jeopardising grain yield. The authors suggest that the improved quality of the NIL may be due to the genomic segment carried along with the Lr24/Sr24 genes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02679-x.

Predictors of Metabolic Complications in Obese Indian Children and Adolescents.

OBJECTIVE: To identify predictors of metabolic complications in obese Indian children and adolescents. METHODS: This cross-sectional study included 282 obese children and adolescents [188 boys, mean (SD) age of 11.7 (3.1) y, body mass index standard deviation score (BMI SDS) 2.4 (0.6)] who underwent metabolic work-up (oral glucose tolerance test, SGPT, lipid profile) and adiposity assessment (waist circumference and Dual energy X-ray absorptiometry). RESULTS: One hundred and fifteen subjects (40.8%) had no metabolic complication (metabolic healthy obesity) with similar prevalence across BMI SDS categories (38.8% for BMI SDS below 2, 42.1% for 2-3 and 40.4% for those above 3). Normal birth weight (odds ratio 3.2, 95% confidence interval 1.0-10.1, p = 0.04), negative family history of type 2 diabetes (odds ratio 1.81, 95% confidence interval 1.0-3.3, p = 0.04) and younger age [11.3 (3.1) y as against 12.1 (3.1) y, p = 0.03] were associated with metabolically healthy obesity. No difference in BMI SDS [2.4 (0.6) as against 2.4 (0.6), p = 0.7], waist circumference SDS [2.0 (0.7) as against 2.2 (0.9), p = 0.07], waist to height ratio [0.6 (0.05) as against 0.6 (0.05), p = 0.1], DXA derived fat percentage [48.6 (5.4)% as against 47.8% (5.2), p = 0.2], android to gynoid ratio [1.05 (0.1) as against 1.06 (0.1), p = 0.08] and fat mass index [13.8 (3.5) as against 13.8 (3.3), p = 0.9] was observed in the two groups. CONCLUSIONS: A substantial proportion of obese children and adolescents do not develop metabolic complications. Birth weight and family history of type 2 diabetes are the only predictors of complications. Further exploration is needed to identify interventional targets.

An innovative technique for electronic transport model of group-III nitrides.

An optimized empirical pseudopotential method (EPM) in conjunction with virtual crystal approximation (VCA) and the compositional disorder effect is used for simulation to extract the electronic material parameters of wurtzite nitride alloys to ensure excellent agreement with the experiments. The proposed direct bandgap results of group-III nitride alloys are also compared with the different density functional theories (DFT) based theoretical results. The model developed in current work, significantly improves the accuracy of calculated band gaps as compared to the ab-initio method based results. The physics of carrier transport in binary and ternary nitride materials is investigated with the help of in-house developed Monte Carlo algorithms for solution of Boltzmann transport equation (BTE) including nonlinear scattering mechanisms. Carrier-carrier scattering mechanisms defined through Coulomb-, piezoelectric-, ionized impurity-, surface roughness-scattering with acoustic and intervalley scatterings, all have been given due consideration in present model. The direct and indirect energy bandgap results have been calibrated with the experimental data and use of symmetric and asymmetric form factors associated with respective materials. The electron mobility results of each binary nitride material have been compared and contrasted with experimental results under appropriate conditions and good agreement has been found between simulated and experimental results.

Celiac Disease in Indian Children and Adolescents with Type 1 Diabetes.

To estimate the time trend and prevalence of celiac disease in 208 children with type 1 diabetes by retrospective case review. Tissue transglutaminase (TTG IgA) levels were done within the first six months of diagnosis and annually on follow-up. Celiac disease was diagnosed in 35 (16.8%; 3 before diagnosis, 18 at initial screening and 14 on follow-up). 14 subjects with negative TTG serology at presentation, developed celiac disease after 3.9 (2.9) years (range 1.4 - 12.6 years, 85.7% within 5 years). Celiac disease is common in Indian children and adolescents with type I diabetes, developing in most within five years of diagnosis.

Substrate free ultrasonic-assisted hydrothermal growth of ZnO nanoflowers at low temperature.

ZnO nanoflowers (NFs) have been synthesised using a simple cost effective ultrasonic-assisted hydrothermal method at low temperature of 95 °C. Here the NFs consist of petal-like arrangement of several hexagonal-shaped nanorods, the length and diameter of which lie in a range of 100-150 nm and 30-70 nm, respectively. ZnO NFs possess hexagonal wurtzite phase, high crystallinity and strong absorption in the UV region. The optical band gap 3.25 eV of these NFs estimated by two different ways is found to be nearly the same. Room temperature photoluminescence spectrum reveals that the ZnO NFs exhibit dominant UV emission and three major emissions in the visible i.e. violet, blue-green and yellow. NFs are promising nanostructures for application in environment related sensors and antimicrobial activity.

Colour Doppler evaluation of uterine and ovarian blood flow in patients of polycystic ovarian disease and post-treatment changes.

AIM: To assess the morphology and colour Doppler parameters in patients with polycystic ovarian syndrome (PCOS) and also to assess the changes in Doppler parameters in follow-up patients, who underwent treatment. MATERIALS AND METHODS: The study was conducted on 50 women of reproductive age who had clinical and biochemical findings suggestive of PCOS. Clinico-hormonal parameters were recorded. Ultrasound and colour Doppler flow measurements of bilateral ovaries were performed in the early proliferative phase of the menstrual cycle. After assessment of the bilateral ovaries, colour Doppler ultrasound was used to evaluate the main uterine artery at the cervico-uterine junction. Follow-up imaging after 3 months was undertaken in patients who underwent treatment (metformin) and changes in the imaging and hormonal parameters were correlated. RESULTS: The mean value of luteinising hormone (LH) and the ratio of LH: follicle-stimulating hormone (FSH) was significantly higher in PCOS patients. Ultrasound parameters were significantly higher in PCOS patients. Ovarian stromal vessels in PCOS patients had a significantly higher peak systolic velocity (PSV), low resistance index (RI), and pulsatility index (PI). The PSV of uterine arteries were significantly decreased and the RI and PI were significantly increased. On follow-up patients revealed changes in hormonal parameters. CONCLUSION: PCOS is a heterogeneous disorder and is a convergence of multisystem endocrine derangements. Ultrasound is good diagnostic tool for PCOS and the use of Doppler aids in the evaluation of haemodynamic changes in small vessels of utero-ovarian circulation and in response assessment.

Effect of Ultraviolet Irradiation on Photo-Physical and Surface Electronic Properties of MoS2.

In this study, exfoliation of molybdenum disulfide (MoS2) using the chemical exfoliation method was successfully achieved via probe sonication followed by centrifugation. The observed ultravioletvisible (UV-Vis) spectra of the MoS2 dispersions indicated the presence of a few layers of MoS2. The morphological, structural, optical and surface electronic properties before and after UV light irradiation were investigated by the technique of X-ray diffraction, the Raman spectroscopic measurements, transmission electron microscopy (TEM), and the scanning Kelvin probe microscopy (SKPM). It was observed that after UV irradiation, the Fermi level moves towards the valence band.

Phonon and magnetoelastic coupling in Al0.5Ga0.5FeO3: Raman, magnetization and neutron diffraction studies.

The intriguing coupling phenomena among spin, phonon, and charge degrees of freedom in materials having magnetic, ferroelectric and/or ferroelastic order have been of research interest for the fundamental understanding and technological relevance. We report a detailed study on structure and phonons of Al0.5Ga0.5FeO3 (ALGF), a lead-free magnetoelectric material, carried out using variable temperature dependent powder neutron diffraction and Raman spectroscopy. Neutron diffraction studies suggest that Al3+ ions are distributed in one tetrahedrally (BO4) and three octahedrally (BO6) coordinated sites of the orthorhombic (Pc21n) structure and there is no structural transition in the temperature range of 7-800 K. Temperature dependent field-cooled and zero-field-cooled magnetization studies indicate ferrimagnetic ordering below 225 K (TN), and that is reflected in the low temperature powder neutron diffraction data. An antiferromagnetic type arrangement of Fe3+ ions with net magnetic moment of 0.13 µB/Fe3+ was observed from powder neutron diffraction analysis and it corroborates the findings from magnetization studies. At the magnetic transition temperature, no drastic change in lattice strain was observed, while significant changes in phonons were observed in the Raman spectra. The deviation of several mode frequencies from the standard anharmonicity model in the ferrimagnetic phase (below 240 K) is attributed to coupling effect between spin and phonon. Spin-phonon coupling effect is discernable from Raman bands located at 270, 425, 582, 695, 738, and 841 cm-1. Their coupling strengths (λ) have been estimated using our phonon spectra and magnetization results. BOn (n = 4, 6) libration (restricted rotation) mode at 270 cm-1 has the largest coupling constant (λ∼ 2.3), while the stretching vibrations located at 695 and 738 cm-1 have the lowest coupling constant (λ∼ 0.5). In addition to the libration mode, several internal stretching and bending modes of polyhedral units are strongly affected by spin ordering.

Factors Associated With Cerebral Edema at Admission in Indian Children with Diabetic Ketoacidosis.

OBJECTIVE: To evaluate the time course and predictors of cerebral edema in diabetic ketoacidosis (DKA). METHODS: Review of hospital records of 107 episodes of DKA between January 2013 to March 2019. RESULTS: Cerebral edema was identified in 26 (24.3%; 22 at presentation and 4 during treatment). Cerebral edema at presentation was associated with lower (<10 mmHg) arterial carbon dioxide (OR 3.6, 95% CI 1.0,12.7; P=0.04), prior fluid treatment (OR 4.7, 95% CI 1.8,12.7; P=0.001) and new onset diabetes (OR 3.5, 95% CI 1.1,11.1; P=0.03). Prior fluid was the only significant predictor on multivariate analysis (P=0.013). Cerebral edema resulted in a longer ICU stay [4.1 (2.3) vs 1.8 (0.9) d; P<0.001]. CONCLUSIONS: Cerebral edema at admission is common in Indian children with DKA and should be suspected with severe metabolic acidosis and inappropriate prior fluid treatment.

Gingerols infusion and multi-step process optimization for enhancement of color, sensory and functional profiles of candied mango.

Presence of pungent gingerols in ginger oleoresin makes it an ideal natural flavoring candidate for the food industry. The study reports its incorporation for synergistic enhancement of flavor and nutraceutical portfolio of candied mango. The process is systematically optimized at bench-scale for gingerols infusion and subsequent candying treatment in a range of hypo and hypertonic osmotic solutions for critical transport properties. After that, optimization of the drying process and the scale-up study was conducted with a 200 folds increase in the batch size. Collated effects of multistep optimization resulted in 85.6, 76.8, 60.2% retention in ß-carotene, total phenolics, Vitamin C, respectively, along with minor color difference and significant improvement in sensory scores over fresh mango. Mass transfer and quality parameters were comparable in both scales, implying excellent repeatability and scalability of the process. Compared with a similar commercial product, substantial improvement in quality characteristics along with 376.7% reduction in overall processing time was achieved.

Marker-assisted transfer of PinaD1a gene to develop soft grain wheat cultivars.

Grain softness has been a major trait of interest in wheat because of its role in producing flour suitable for making high-quality biscuits, cookies, cakes and some other products. In the present study, marker-assisted backcross breeding scheme was deployed to develop advanced wheat lines with soft grains. The Australian soft-grained variety Barham was used as the donor parent to transfer the puroindoline grain softness gene Pina-D1a to the Indian variety, DBW14, which is hard grained and has PinaD1bPinbD1a genes. Foreground selection with allele-specific PCR-based primer for Pina-D1a (positive selection) was used to identify heterozygous BC1F1 plants. Background selection with 173 polymorphic SSR primers covering all the 21 chromosomes was also carried out, in the foreground-selected BC1F1 plants. BC1F2 plants were selected by ascertaining the presence of Pina-D1a (positive selection) and absence of Pina-D1b (negative selection). Using the approach of positive, negative and background selection with molecular markers, 15 BC1F2 and 31 BC2F1 plants were finally selected. The 15 BC1F2 plants were selfed and the 31 BC2F1 plants were further backcrossed and selfed to raise BC3F1 and BC2F2 progenies, respectively. A part of the BC2F2 seed of each of the 31 plants was analyzed for grain hardness index (GHI) with single-kernel characterization system. The GHI varied from 12.1 to 37.1 in the seeds borne on the 31 BC2F1 plants. The reasons for this variation and further course of action are discussed.

Microscopic characterisation of photodetectors used in the hadron calorimeter of the Compact Muon Solenoid experiment.

The Hybrid Photodetector (HPD) is a hybrid unit with a single accelerating gap between a common photocathode and an array of PIN diodes. Customised HPDs with 19 channels were used to detect scintillation light from hadron calorimeter in the Compact Muon Solenoid (CMS) experiment. In this paper, we present results on radiation damage studies carried out on the used HPDs in the outer hadron (HO) and the end-cap hadron (HE) calorimeter of the CMS experiment operating at CERN. The calorimeter is made of alternating layers of scintillating tiles and metals, such as brass or iron. The scintillating light was transmitted to the HPDs by means of optical fibres. Due to excessive exposure to scintillation light and ionising radiation during data taking at the Large Hadron Collider, the performance of the HPDs was expected to degrade significantly in the HE detector. Independent studies on radiation damage of these used photosensors were important to assess the degradation in the performance of the calorimeter. Microscopic scans of relative photon detection efficiencies for two HPDs (one each from HO and HE detector) were made using micron resolution optical scanner. The scanner was specially designed and built for microscopic characterisation of photosensors. Imprints of each fibre (∼1 mm in diameter) on the photocathode with varying damage within the same pixel of the HPD were observed. The localised damage of the photocathode was determined to vary with the amount of scintillation (or calibration) light transmitted by optical fibres to the HPD.