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2.
Eur J Pediatr ; 183(4): 1849-1855, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38276999

ABSTRACT

Clinical parameters used for hemodynamic assessment and titration of vasopressor therapy in neonates with septic shock have several limitations. Functional echocardiography is an emerging tool for bedside assessment of cardiac function and may be useful for diagnosis of shock and assessing the response to therapy. Data regarding echocardiographic parameters in neonates with shock is lacking. This prospective observational study was conducted in a Level III NICU with the primary objective of comparing echocardiographic characteristics of neonates with septic shock at diagnosis, following fluid boluses, and after maximum inotropic support [A1]. Additionally, we compared these characteristics with those of healthy stable neonates who were gestation and postnatal age-matched. A total of 36 neonates with septic shock and 30 gestation and postnatal age-matched controls were enrolled. The mean (SD) gestation and birth weight of neonates with septic shock were 30.6 (4.0) weeks and 1538 (728) g, respectively. Gram-negative bacilli constituted 78.9% of all isolates. At presentation, there was no significant difference between neonates with shock and controls in terms of ventricular outputs, shortening fraction, ratio of early to late diastolic trans-mitral flow velocity, and myocardial performance indices. The distensibility index of inferior vena cava was higher in neonates with shock compared to controls, (17% vs 10%, (p < 0.01)). Left ventricular output was 209 (92) and 227 (102) ml/kg/min (p = 0.53) and right ventricular output was 427 (203) and 459 (227) ml/kg/min, (p = 0.03), respectively, before and after inotropic therapy.     Conclusion: Echocardiographic parameters may not differentiate neonates with septic shock from hemodynamically stable neonates. Neonates with shock associated with predominantly gram-negative sepsis are not able to augment cardiac functions, either at the onset or after administration of inotropes.      Trial registration: (CTRI/2017/12/010766). What is known: • For neonates with shock, echocardiography is becoming increasingly popular as an objective method of evaluating hemodynamics. • In healthy preterm neonate, cardiac output has been known to increase in response to altered hemodynamics during states of increased oxygen demand. What is new: •  In the setting of septic shock induced by gram-negative organisms, echocardiographic parameters are less likely to assist in the assessment of the response to vasoactive agents. Cytokines, induced by gram-negative organisms, may alter adrenoreceptors in myocardium and vasculature.


Subject(s)
Shock, Septic , Infant, Newborn , Humans , Shock, Septic/diagnostic imaging , Shock, Septic/therapy , Echocardiography , Hemodynamics , Cardiac Output/physiology , Heart Ventricles
3.
Indian J Pediatr ; 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-38036913
4.
Phys Chem Chem Phys ; 25(41): 28473-28478, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37846758

ABSTRACT

Doping-assisted lattice site engineering is widely practiced to obtain a tailor made response, which subsequently poses a need for an efficient probe of the local electronic structure of the system. This study presents a detailed analysis of the local electronic structure around the host cations (Zn2+ and Sr2+) and dopant (Dy3+) through combined experimental and simulated X-ray absorption near edge structure. The real space full multiple scattering-based simulations of the Zn K-edge are done by substituting Dy at cationic sites in the second coordination shell around Zn, in various combinations along with and/or without oxygen vacancies in the system. The results revealed that Dy tends to substitute the less symmetric Sr2+ site at low doping concentration, whereas it starts substituting the relatively more symmetric Zn2+ lattice site with an increase in doping concentration, consequently affirming the origin of cold white emission upon charge transfer in the system (Manju, M. Jain, P. Vashishtha, G. Gupta, A. Sharma, S. O. Won, A. Vij and A. Thakur, J. Phys.: Condens. Matter, 2020, 33, 035703). The effect of Zn site occupancy is seen as bifurcation of the single peaked Dy L3 absorption edge, which is usually reported as the sole indication of the existence of a mixed valence state. Thus, the combined analyses decipher the effect of lattice site occupancy on the local electronic structure of host as well as dopant atoms.

5.
Clin Exp Allergy ; 53(7): 697-710, 2023 07.
Article in English | MEDLINE | ID: mdl-37340789

ABSTRACT

India is a low-middle income country with a population of 1.4 billion and home to one quarter of the world's children. Exclusive breastfeeding until 6 months and continued breastfeeding until at least 2 years as per global recommendations are common practice. The Indian government and associated organisations have strived to protect breastfeeding, which is important in a country with high under-5 mortality, malnutrition and stunting. Allergic disease is under-recognised in India, but despite the absence of a dedicated allergy medical specialty, awareness of allergy is increasing among healthcare practitioners and in the general population. In high-income countries, overdiagnosis of allergy has become recognised as an issue in recent years. Allergy healthcare professionals have also attracted criticism for close relationships with the formula industry, which appear to have contributed to excessive use of specialised formula products and undermining of breastfeeding. Specialised formula has been used unnecessarily for preventing allergy, based on fraudulent and selectively reported science; and for managing normal infant symptoms which are mislabelled as milk allergy. This forms part of a broader formula industry corporate strategy to widen the boundaries of illness in order to expand sales and markets. In India, allergic disease management is hindered by limited understanding of the disease entity among practitioners, low access to diagnostics, limited healthcare resources, high exposure to air pollution and a large, diverse population. Data specific to India on allergic disease prevalence and interpreting allergy diagnostics are incomplete. The knowledge gaps mean allergy management in India is often extrapolated from guidance developed in high-income countries with low breastfeeding rates. As the allergy specialty develops in India, local guidance and practice will need to recognise the threat that current allergy practice poses to India's normative infant feeding culture, and ensure that breastfeeding continues to be supported at all levels.


Subject(s)
Breast Feeding , Milk Hypersensitivity , Infant , Child , Female , Humans , Milk Hypersensitivity/epidemiology , India/epidemiology
7.
Am J Perinatol ; 2023 May 19.
Article in English | MEDLINE | ID: mdl-37059454

ABSTRACT

OBJECTIVE: Early establishment of enteral feeds is desirable in very preterm infants, but it may be associated with feeding intolerance. Several feeding methods have been studied with no strong evidence to suggest the preferred feeding method to establish early full enteral feeds. We studied three modalities of feeding in preterm infants ≤32 weeks and ≤1,250 g: continuous infusion (CI), intermittent bolus by infusion (IBI), and intermittent bolus by gravity (IBG) for their effect on time to reach full enteral feeds of 180 mL/kg/d. STUDY DESIGN: We randomized 146 infants, 49 infants in each CI and IBI group and 48 infants in the IBG group. In the CI group, feeds were delivered by an infusion pump continuously over 24 hours. In the IBI group, feeds were given every 2 hours and infused over 15 minutes by an infusion pump. In the IBG group, feeds were delivered by gravity over 10 to 30 minutes. The intervention was continued till infants reached direct breast/cup feeds. RESULTS: The mean (standard deviation) gestation in CI, IBI, and IBG groups were 28.4 (2.2), 28.5(1.9), and 28.6 (1.8) weeks, respectively. The time to reach full feeds in CI, IBI, and IBG were not significantly different (median [interquartile range]: 13 [10-16], 11.5 [9-17], and 13 [9.5-14.2] d, respectively, p = 0.71). The proportions of infants who developed feeding intolerance in CI, IBI, and IBG were similar (n [%]: 21 [51.2%], 20 [52.6%], and 22 [64.7%], respectively, p = 0.45). There was no difference in necrotizing enterocolitis ≥2 (p = 0.80), bronchopulmonary dysplasia (p = 0.86), intraventricular hemorrhage ≥2 (p = 0.35), patent ductus arteriosus requiring treatment (p = 0.44), retinopathy of prematurity requiring treatment (p = 0.51), and growth parameters at discharge. CONCLUSION: In preterm infants, ≤32 weeks of gestation and birth weight ≤1,250 g, there was no difference in time to reach full enteral feeds in the three modalities of feeding. This study is registered with Clinical Trials Registry India (CTRI) and the registration number is CTRI/2017/06/008792. KEY POINTS: · Gavage feeding in preterm infants is either continuous or intermittent bolus feeding.. · Intermittent bolus feeding was evaluated in a controlled time by infusion over 15 minutes.. · The time to reach full feeds was comparable for all three methods..

8.
Heliyon ; 9(3): e13865, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36873537

ABSTRACT

BN50/NiO50 and Au-loaded BN50/NiO50 nanocomposite films were separately fabricated on the glass substrates for carrier transport and photoconductivity properties. X-ray diffraction pattern of the films show the hexagonal structure of BN and presence of defect states by Nelson Riley factor analysis. Morphological images show spherical shaped particles with highly porous structure. The incorporation of NiO may hindered growth of BN layers and resulted in spherical particles. Temperature-dependent conductivity describes semiconductor transport behaviour for deposited nanocomposite films. Thermal activation conduction with low activation energy (∼0.308 eV) may be responsible for the resulting conductivity. Further, the light intensity dependent photoelectrical properties of BN50/NiO50 and Au-loaded BN50/NiO50 nanocomposites have been explored. The effect of Au nanoparticles loading on enhanced photo-conductivities (∼22% increase) than bare nanocomposite film has been elaborated by proposed mechanism. This study provided the insightful information for carrier transport and photoconductivity of BN-based nanocomposites.

9.
Indian Pediatr ; 60(1): 72-74, 2023 01 15.
Article in English | MEDLINE | ID: mdl-36639975

ABSTRACT

We retrieved data of ultrasound-guided neonatal internal jugular vein (IJV) cannulations done between November, 2020 and March, 2021. Of the 33 ultrasound-guided IJV cannulation in neonates, 32 were successful with overall success rate of 97%. Median (IQR) number of attempts per insertion was 2 (1,3.5). There were no major complications observed during the insertion of the catheter. In one instance, inadvertent carotid artery puncture was encountered, without significant bleeding.


Subject(s)
Catheterization, Central Venous , Infant, Newborn , Humans , Catheterization, Central Venous/adverse effects , Jugular Veins/diagnostic imaging , Neonatologists , Ultrasonography, Interventional , Prospective Studies
10.
Article in English | MEDLINE | ID: mdl-36626847

ABSTRACT

The UV/Visible activated near-infrared (NIR) phosphors have many applications in solid state lighting, night vision devices and bio-imaging. The early research reported the red-NIR emitting phosphors doped with Cr3+centers upon visible light excitation. Here, in this work the intense red-NIR emission and color tuning is achieved for broad excitation range (UV/blue/green) through Cr dopant induced defect centers and cation inversionWe present the infuence of Cr dopant induced defect centers and cation inversion in Mg1-xCrxAl2O4(x= 0.5, 1, 3, 5 and 10 mol%) nanocrystals. The Cr3+doped MgAl2O4nanocrystals were synthesized by combustion method through stoichiometric substitution of Mg by Cr, while most of the Cr3+ions occupied the octahedral sites of spinel host with the formation of antisite defects, Cr3+clusters, magnesium and oxygen vacancies. These defect centers were probed through Rietveld refinement, PL, X-ray photoelectron and nuclear magnetic resonance spectra analyses. At UV excitation, the intrinsic defects played an interesting role in exhibiting the blue-violet emission attributed to host lattice defects and red-NIR emission attributed to strong/weak ligand field octahedral Cr3+sites, via charge transfer to Cr3+ions. The PL spectra evinced the enhanced red-NIR emission intensity upon 266 nm excitation than upon blue and green light excitation. Further, the weak ligand field site emission is found to be dominating with increase in doping concentration. Thus, Cr doped MgAl2O4nanocrystals showed their potency of exhibiting the intense red-NIR emission and color tuning (from red purple to bluish purple and then to red color) upon UV/blue/green excitation.

11.
J Med Imaging Radiat Oncol ; 67(1): 54-64, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36268679

ABSTRACT

Point of care lung ultrasound (USG) can help in the diagnosis and management of critically sick neonates. It is based on seven simple principles that are comprehensive enough to diagnose all major lung pathologies. A compact small machine and a micro-convex or linear probe are the basic requirements to perform lung USG. In contrast to traditional USG principles, USG of the lung is based on artefacts. Some of the terminologies that are used to characterize normal lung include the pleural line, A-line, bat sign, lung sliding and seashore sign. Air/fluid mixture in varying ratios helps in diagnosis of normal lung, pneumothorax, interstitial syndrome (transient tachypnoea of newborn, respiratory distress syndrome, bronchopulmonary dysplasia), lung consolidation and pleural effusion.


Subject(s)
Lung Diseases , Pleural Effusion , Pneumothorax , Infant, Newborn , Humans , Lung/diagnostic imaging , Ultrasonography
13.
J Matern Fetal Neonatal Med ; 35(25): 7748-7755, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34121586

ABSTRACT

INTRODUCTION: Neonatal encephalopathy (NE) is associated with a high risk of adverse neurological outcomes. Several neurodiagnostic tests have been evaluated to predict the prognosis. Amplitude integrated Electroencephalogram (aEEG) is now being commonly used for bedside evaluation of cerebral function. There is limited data on the role of aEEG for prognostication in NE, from resource-limited settings. OBJECTIVE: To evaluate the predictive ability of aEEG for abnormal neurological outcomes in neonatal encephalopathy or neonates with encephalopathy. METHODS: Neonates above 35 weeks of gestation admitted to NICU in a tertiary care hospital with a diagnosis of encephalopathy were enrolled. Clinical characteristics severity of encephalopathy and seizures were recorded. Amplitude integrated recording was started at admission and continued till recovery of trace to normal or for 10 days. The primary outcome was death or abnormal neurological status at 3-6 months of age. The study was registered in the Clinical Trial Registry of India (CTRI/2013/05/003612). RESULTS: The incidence of NE was 6% of total admission. Moderate and severe encephalopathy occurred in 58 and 39% of babies respectively. Hypoxic-ischemic encephalopathy was the most common cause. Clinical seizures occurred in 91% of cases. An abnormal aEEG trace was observed in 51 (76.1%) infants with NE. For adverse neurological outcomes at an age average of 4.5 months of age, aEEG had a sensitivity, specificity, NPV, and PPV of 100, 54.2, 100, and 77.5, respectively. CONCLUSIONS: Clinical staging and aEEG has good predictive ability to detect an adverse neurological outcome. aEEG improves the ability to predict abnormal outcome in babies with moderate encephalopathy. Early recovery of aEEG abnormality correlates with better neurodevelopmental outcomes.KEY MESSAGESWhat's known: aEEG is a useful modality to assess neurodevelopmental outcomes however data from developing countries is lacking.What's new: aEEG monitoring in babies in neonatal encephalopathy may improve the prediction of abnormal neurological outcomes in babies with moderate encephalopathy.


Subject(s)
Hypoxia-Ischemia, Brain , Infant, Newborn, Diseases , Humans , Infant , Infant, Newborn , Electroencephalography , Hypoxia-Ischemia, Brain/complications , Hypoxia-Ischemia, Brain/diagnosis , Infant, Newborn, Diseases/diagnosis , Infant, Newborn, Diseases/epidemiology , Prognosis , Seizures/diagnosis , Seizures/etiology
14.
Pediatr Infect Dis J ; 41(2): 156-160, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34890377

ABSTRACT

BACKGROUND: Optimal duration of antibiotic therapy in Gram-negative bacterial (GNB) sepsis in non-VLBW infants has not been specifically evaluated in previous studies. METHODS: This was an open labeled noninferiority randomized controlled trial. Non-VLBW infants with GNB sepsis without meningitis whose blood culture were sterile after day 7 of treatment and who were in clinical remission on day 9 of appropriate antibiotic were randomized to short duration (SDR) group and long duration (LDR) group. Infants in SDR group and LDR group received antibiotic therapy for 10 days and 14 days respectively. Primary objective was to compare treatment failure. Secondary objectives were to compare duration of hospitalization, complications of intravenous (IV) therapy and its duration, episodes of new-onset sepsis and all-cause mortality. RESULTS: Of 222 infants with GNB sepsis, 58 eligible infants were randomized in each group and 113 of these were analyzed. There was no difference in proportion of infants with multidrug-resistant (MDR) organism in SDR versus LDR group [33(60%) versus 32(55.1%) (P = 0.84)]. There were no treatment failures in either group. Median (IQR) duration of hospital stay was higher in LDR group as compared with SDR group: 20(18, 23) versus 16(13, 20) days (P < 0.001). Infants in LDR group required IV therapy for a longer duration as compared with SDR group mean (SD): 15.2(1.2) versus 10.9(0.8) days (P < 0.001). Median (IQR) episodes of extravasation were higher in LDR group: 5(4.7) versus 3(2.3) (P < 0.001). There was no difference in episodes of phlebitis and hematoma. No infants had died on follow up. CONCLUSION: In suitably selected non-VLBW infants with Gram-negative sepsis, 10 days therapy is noninferior to 14 days therapy.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Bacteremia/drug therapy , Gram-Negative Bacterial Infections/drug therapy , Neonatal Sepsis/drug therapy , Anti-Bacterial Agents/therapeutic use , Bacteremia/microbiology , Female , Gram-Negative Bacterial Infections/microbiology , Humans , Infant, Newborn , Male , Neonatal Sepsis/microbiology , Treatment Failure
15.
Eur J Pediatr ; 180(12): 3527-3534, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34143245

ABSTRACT

We conducted an exploratory longitudinal study to evaluate the macronutrient composition of human milk in mothers delivering very preterm infants ≤ 32 weeks over the first 4 weeks of lactation and the association of human milk composition with maternal and neonatal factors A total of 213 human milk samples collected in the morning between 8 am and 12 pm from 60 eligible mothers were analyzed on 7 (n = 60), 14 (n = 60), 21 (n = 52), and 28 (n = 41) days of lactation by infrared transmission spectroscopy. The true protein content decreased significantly over 4 weeks (mean difference (95% confidence interval)) (MD (95% CI)) week 1 and week 4 = 0.2 g (0.037 to 0.363, P = 0.009)). On the contrary, the mean fat and calorie content showed significant increase over time (MD (95% CI)) = - 1.03 g (- 1.719 to - 0.343, P = 0.001) and - 9.0 kcal/dl (- 15.170 to - 2.830, P = 0.001), respectively). There was no difference in the carbohydrate content of human milk over 4 weeks. Macronutrient composition was independent of maternal parity, mode of delivery, pre-pregnancy body mass index, umbilical artery Doppler flows, previous breast feeding experience, neonatal centile status, gestation, and infant's weight at birth. Multiple regression analysis of human milk composition with mother's dietary components showed no significant association. CONCLUSION : We conclude that in mothers who deliver very preterm infants ≤ 32 weeks, true protein content decreased, fat and calorie content increased, and carbohydrate content remained stable in human milk during first 4 weeks of lactation. Human milk macronutrient composition was independent of various maternal and neonatal factors including maternal body mass index and dietary intake. TRIAL REGISTRATION : CTRI/2017/02/007895 What is Known: • Preterm human milk has high temporal and inter-individual variation in the macronutrient composition. What is New: • In mothers who deliver very preterm infants < 32 weeks, true protein content decreases, fat and calorie content increases, and carbohydrate content remains stable in human milk during first 4 weeks of lactation. • Human milk macronutrient composition is independent of various maternal and neonatal factors including maternal body mass index and dietary intake.


Subject(s)
Milk, Human , Mothers , Female , Humans , Infant , Infant, Newborn , Infant, Premature , Lactation , Longitudinal Studies , Nutrients , Pregnancy
16.
Indian Pediatr ; 58(2): 140-143, 2021 02 15.
Article in English | MEDLINE | ID: mdl-33632944

ABSTRACT

OBJECTIVE: To compare outcomes of very low birth weight (VLBW) neonates before and after the change in practice for treatment of PDA. METHODS: Medical records of VLBW neonates were reviewed. Neonates were categorized in two groups: Period I (January, 2012 to July, 2015) and Period II (August, 2015 to December, 2016). The primary outcome of study was composite outcome of death or broncho-pulmonary dysplasia (BPD). RESULTS: The composite outcome (Death/BPD) was comparable in two groups; adjusted OR (95% CI) 1.1 (0.6, 1.9). Mortality and severe BPD were also comparable. The pharmacological treatment for PDA was required in 8.4% vs 2.6% of VLBW neonates during Period I and II, respectively (P=0.03). Durations of invasive and noninvasive ventilation were comparable during two periods. CONCLUSIONS: Restrictive threshold for management of PDA in VLBW neonates may not be associated with increase in morbidities or mortality and possibly would reduce need for pharmacological treatment or surgical ligation.


Subject(s)
Ductus Arteriosus, Patent , Ductus Arteriosus, Patent/drug therapy , Humans , Infant, Newborn , Infant, Very Low Birth Weight , Ligation , Morbidity , Retrospective Studies
17.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 76(Pt 5): 757-768, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-33017309

ABSTRACT

The correlation of several defects and optical and magnetic properties with Fe content in Zn1-xFexAl2O4 (0.01 ≤ x ≤ 0.40) nanocrystals has been scrutinized through X-ray diffraction, O K-edge X-ray absorption near-edge structure, FT-IR, diffuse reflectance, photoluminescence and electron spin-resonance spectroscopies, and vibrating sample magnetometry. Increasing Fe content causes elongation in the octahedral units of the lattice, accompanied by distortion in the octahedral coordination. Fe introduces non-radiative centres in the forbidden gap, thereby tuning the band gap from 4.37 to 3.88 eV and eliminating emission in the visible region. Zn vacancies are found to tail off, while {\rm Fe}_i^{\bullet \bullet \bullet}, {\rm Al}_{\rm Zn}^\bullet and FeAl× antisite defects increase in concentration with increasing Fe content. Inhomogeneous broadening of spin-resonance signals infers strong spin-lattice interactions of Fe3+ ions at distorted octahedral and non-symmetric tetrahedral sites. A transition is observed from paramagnetism to superparamagnetism at higher Fe concentrations. A visual colour change from pearly white to orange-brown is observed in Zn1-xFexAl2O4 nanocrystals with increasing Fe content, revealing its potential candidature for pigments in the paint and dye industries.

18.
Sci Rep ; 10(1): 17364, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-33060718

ABSTRACT

We report, for the first time, the influence of oxygen vacancies on band structure and local electronic structure of [Formula: see text] (SZO) nanophosphors by combined first principle calculations based on density functional theory and full multiple scattering theory, correlated with experimental results obtained from X-ray absorption and photoluminescence spectroscopies. The band structure analysis from density functional theory revealed the formation of new energy states in the forbidden gap due to introduction of oxygen vacancies in the system, thereby causing disruption in intrinsic symmetry and altering bond lengths in SZO system. These defect states are anticipated as origin of observed photoluminescence in SZO nanophosphors. The experimental X-ray absorption near edge structure (XANES) at Zn and Sr K-edges were successfully imitated by simulated XANES obtained after removing oxygen atoms around Zn and Sr cores, which affirmed the presence and signature of oxygen vacancies on near edge structure.

19.
Indian Pediatr ; 57(9): 805-807, 2020 09 15.
Article in English | MEDLINE | ID: mdl-32999108

ABSTRACT

OBJECTIVE: To assess feasibility of ultrasound (USG) evaluation of tip position of central catheter in neonates and to determine agreement between radiograph and USG-based assessments. METHODS: This prospective observational study was conducted in a tertiary neonatal intensive care unit from April, 2019 to August, 2019. Point of care USG and radiograph were performed on infants who underwent central line placement. Agreement between the two was determined using Kappa statistics. RESULTS: Of the 141 central catheters insertions performed, USG was performed for 65 central catheters. On USG, catheter tip position could be assessed and defined in 62 (95%) of cases. Of these 62 central lines, 24 (38.7%) were defined as optimally placed on radiograph and 20 (32.2%) were defined as optimally placed on USG. There was excellent agreement between radiographic and USG assessment of catheter tip position [K (95% CI) = 0.86 (0.73-0.99), P <0.001]. All 38 lines found to be mal-positioned on radiograph were assessed as sub-optimal on USG as well. CONCLUSIONS: Point of care USG has excellent agreement with radiography for confirming central line tip position.


Subject(s)
Catheterization, Central Venous , Central Venous Catheters , Humans , Infant , Infant, Newborn , Intensive Care Units, Neonatal , Point-of-Care Systems , Ultrasonography
20.
Article in English | MEDLINE | ID: mdl-32992301

ABSTRACT

In presented work, excitation selective novel cool and cold white emission is reported from dysprosium (Dy) doped SrZnO2nanophosphors, synthesized by combustion technique. The host lattice provided selective excitation routes for Dy3+levels and intrinsic defects levels via charge transfer (270 nm) and host defects absorption bands (375 nm), respectively. The emission due to Dy3+levels was found to be exhibiting cool white emission and that from intrinsic defects was cold white emission, as characterized from correlated color temperature. UV irradiated glow curve analysis complemented the results by exhibiting signal due to Dy assisted traps on near UV exposure (254 nm) and that of host related traps at far UV exposure (365 nm). The luminescence phenomenon is comprehended through proposed band model. The obtained results proclaimed SrZnO2:Dy as a potential member among white emitting phosphors to be used as standard daylight sources in commercial and aesthetic lighting.

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