Stalk rot species diversity and molecular phylogeny associated with diseased maize in India.

Stalk rot disease is a major constraint in maize production and till date reported to be caused by two to three species of phytopathogenic fungi but, in our present study, we disclose the first report of stalk rot is caused by complex species of phytopathogens, which belongs to five different genera. Therefore, to substantiate these findings, a total of 105 diseased samples of maize were collected from 21 different locations in six different geographical locations of India from which 48 isolates were used for the research study. Morphological features such as pigmentation, colony color, type of mycelium and pattern of mycelium was examined using macro and microscopic methods. A total of 11 different spp. of pathogens belonging to the five different genera: Fusarium verticillioides (56.25%), F. equiseti (14.5%), F. andiyazi (6.25%), F. solani (2.08%), F. proliferatum (2.08%), F. incarnatum (2.08%), Lasidioplodia theobrame (6.25%), Exserohilum rostrtum (4.16%), Nigrospora spp. (4.16%). and Schizophyllum commune (2.08%) were identified by different housekeeping genes (ITS, TEF-1α, RPB2 and Actin). Fusarium verticillioides, F. equiseti and F. andiyazi were major pathogens involved in stalk rot. This is the first report on F. proliferatum, F. solani, F. incarnatum, Lasidioplodia theobrame, Exserohilum rostrtum, Nigrospora spp. and Schizophyllum commune causing stalk rot of maize and their distribution in the different states of India. Studies on population dynamics of PFSR will enhance the understanding of pathogen behavior, virulence, or its association with different pathogens across India, which will facilitate the development of resistant maize genotypes against the PFSR.

Advances in Hierarchical Inorganic Nanostructures for Efficient Solar Energy Harvesting Systems.

The urgent need to address the global energy and environmental crisis necessitates the development of efficient solar-power harvesting systems. Among the promising candidates, hierarchical inorganic nanostructures stand out due to their exceptional attributes, including a high specific surface area, abundant active sites, and tunable optoelectronic properties. In this comprehensive review, we delve into the fundamental principles underlying various solar energy harvesting technologies, including dye-sensitized solar cells (DSSCs), photocatalytic, photoelectrocatalytic (water splitting), and photothermal (water purification) systems, providing a foundational understanding of their operation. Thereafter, the discussion is focused on recent advancements in the synthesis, design, and development of hierarchical nanostructures composed of diverse inorganic material combinations, tailored for each of these solar energy harvesting systems. We meticulously elaborate on the distinct synthesis methods and conditions employed to fine-tune the morphological features of these hierarchical nanostructures. Furthermore, this review offers profound insights into critical aspects such as electron transfer mechanisms, band gap engineering, the creation of hetero-hybrid structures to optimize interface chemistry through diverse synthesis approaches, and precise adjustments of structural features. Beyond elucidating the scientific fundamentals, this review explores the large-scale applications of the aforementioned solar harvesting systems. Additionally, it addresses the existing challenges and outlines the prospects for achieving heightened solar-energy conversion efficiency.

Stem and leaf rust-induced miRNAome in bread wheat near-isogenic lines and their comparative analysis.

Wheat rusts remain a major threat to global wheat production and food security. The R-gene-mediated resistance has been employed as an efficient approach to develop rust-resistant varieties. However, evolution of new fungal races and infection strategies put forward the urgency of unravelling novel molecular players, including non-coding RNAs for plant response. This study identified microRNAs associated with Sr36 and Lr45 disease resistance genes in response to stem and leaf rust, respectively. Here, small RNA sequencing was performed on susceptible and resistant wheat near-isogenic lines inoculated with stem and leaf rust pathotypes. microRNA mining in stem rust-inoculated cultivars revealed a total of distinct 26 known and 7 novel miRNAs, and leaf rust libraries culminated with 22 known and 4 novel miRNAs. The comparative analysis between two disease sets provides a better understanding of altered miRNA profiles associated with respective R-genes and infections. Temporal differential expression pattern of miRNAs pinpoints their role during the progress of infection. Differential expression pattern of miRNAs among various treatments as well as time-course expression of miRNAs revealed stem and leaf rust-responsive miRNAs and their possible role in balancing disease resistance/susceptibility. Disclosure of guide strand, passenger strand and a variant of novel-Tae-miR02 from different subgenome origins might serve as a potential link between stem and leaf rust defence mechanisms downstream to respective R-genes. The outcome from the analysis of microRNA dynamics among two rust diseases and further characterization of identified microRNAs can contribute to significant novel insights on wheat-rust interactions and rust management. KEY POINTS: • Identification and comparative analysis of stem and leaf rust-responsive miRNAs. • Chromosomal location and functional prediction of miRNAs. • Time-course expression analysis of pathogen-responsive miRNAs.

Biomolecule conjugated inorganic nanoparticles for biomedical applications: A review.

Last decade has witnessed impressive progress in the fields of medicine and bioengineering with the aid of nanomaterials. Nanomaterials are favoured for their improved bio-chemical as well as mechanical properties with tremendous applications in biomedical domains such as disease diagnosis, targeted drug delivery, medical imaging, in vitro diagnostics, designing innovatory cross-functional implants and regenerative tissue engineering. The current situation insists upon crafting nanotools that are capable of catering to biological needs and construct more efficient biomedical strategies. In the recent years, surface functionalization and capping with biomolecules has initiated substantial interest towards research. In this regard, search of suitable biofunctionalized nanoparticles seem to be like finding pearls from ocean. Conjugating biological molecules with inorganic materials has paved the way for unravelling innovative functional materials with dramatically improved properties and a wide range of uses. Inorganic nanoparticles such as metals, metal oxides, as well as quantum dots have been hybridised or conjugated with biomolecules such as proteins, peptides, carbohydrates, and nucleic acids. The present review reports on various biomolecule functionalized inorganic nanomaterials highlighting the biomolecule-inorganic nanoparticle interaction studies, the mechanism of functionalization, antimicrobial efficacy of the functionalised nanoconjugates and its use in various biomedical applications.

Hydrothermal synthesis of novel heterostructured Ag/TiO2 /CuFe2 O4 nanocomposite: Characterization, enhanced photocatalytic degradation of methylene blue dye, and efficient antibacterial studies.

In this work, we reported the successful synthesis of novel Ag/TiO2 /CuFe2 O4 ternary nanocomposite by hydrothermal technique by using TiO2 /CuFe2 O4 binary nanocomposite precursor that was also prepared by hydrothermal treatment by using TiO2 nanoparticles and CuFe2 O4 nanoparticles synthesized via sol-gel method. The synthesized nanomaterials were accessed for their morphological, structural, and optical properties. X-ray diffraction (XRD) study reveals the formation of pure Ag/TiO2 /CuFe2 O4 ternary nanocomposite in which the Ag, TiO2 , and CuFe2 O4 are in anatase, spinal, and cubic crystal phases, respectively. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) analyses of Ag/TiO2 /CuFe2 O4 ternary nanocomposite indicated granule-shaped morphology with bright spots of silver. The existence of Ti, O, Cu, Fe, and Ag without any other elements in the energy-dispersive X-ray spectroscopy (EDS) spectra of the prepared ternary nanocomposite depict its purity and its polycrystalline nature was confirmed by its selected area electron diffraction (SAED) pattern. The ternary nanocomposite was utilized for the methylene blue dye degradation with an optimum dose of 1.00 g/100 ml under ultraviolet (UV) light; the enhanced photocatalytic activity of the composite is attributed mainly due to the appreciable magnitudinal difference of positive charge of the valence band and negative charge of the conduction band of TiO2 and CuFe2 O4 ; meanwhile, the interfacially placed Ag acts as a sink for the elections. Also, the ternary nanocomposite showed satisfactory antibacterial activities. PRACTITIONER POINTS: The prepared ternary nanocomposite showed effective results in dye degradation and satisfactory antibacterial property. The concentration of methylene dye has decreased considerably in every degradation process which was accessed through UV-vis studies. The highest degradation by using the ternary nanocomposite archived at pH = 6 Appreciable antibacterial activity was achieved against a few Gram-positive strains and Gram-negative strains of bacteria. This research activity can open a broad area of research towards textile dye degradation and antibacterial studies.

Mechanistic insights into defect chemistry and tailored photoluminescence and photocatalytic properties of aliovalent cation substituted Zn0.94M0.06-xLixO (M: Fe3+, Al3+, Cr3+) nanoparticles.

In this work, we demonstrate the microwave assisted solution combustion synthesis of aliovalent cation substituted Zn0.94M0.06-xLixO (M: Fe3+, Al3+, Cr3+) nanoparticles. The structural features, photoluminescence and photocatalytic properties were characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and UV-visible and photoluminescence (PL) techniques. We have introduced aliovalent cations such as reducible Fe3+, stable Al3+ and oxidisable Cr3+ ions into ZnO and investigated its structural and optical properties. The charge balance and defect stoichiometric composition of ZnO were also studied by co-doping with Li+ ions. By understanding the photoluminescence and photocatalytic activity of doped and co-doped ZnO nanoparticles, the defect chemistry of ZnO is explained in detail. The photocatalytic efficiency of various doped and co-doped ZnO catalysts was compared with respect to the degradation of rhodamine B dye. Among them, the CZO, AZO and L3AZO catalysts showed enhanced photo-degradation efficiencies of 98.1%, 97.6% and 96.6%, respectively, which are high as compared to that of ZnO (89%). This work presents a novel and straightforward, low-cost, tunable and scalable fabrication protocol for highly efficient ZnO-based photocatalysts for practical applications.

Solvent-free benzylic oxidation of aromatics over Cu(II)-containing propylsalicylaldimine anchored on the surface of mesoporous silica catalysts.

A sustainable method was used to produce aromatic ketones by the solvent-free benzylic oxidation of aromatics over mesoporous Cu(II)-containing propylsalicylaldimine anchored on the surface of Santa Barbara Amorphous type material-15 (CPSA-SBA-15) catalysts. For comparison, mesoporous Cu(II)-containing propylsalicylaldimine anchored with Mobil Composition of Matter-41 (CPSA-MCM-41) was assessed for these reactions under similar reaction conditions. The washed CPSA-SBA-15(0.2) (W-CPSA-SBA-15(0.2)) catalyst was prepared using an easy chemical method for the complete removal of non-framework CuO nanoparticle species on the surface of pristine CPSA-SBA-15(0.2) (p-CPSA-SBA-15(0.2) prepared with 0.2 wt% of Cu, and its catalytic activity was evaluated with different reaction parameters, oxidants and solvents. In order to confirm the catalytic stability, the recyclability was assessed, and the performance of hot-filtration experiments was also evaluated. All the catalysts used for these catalytic reactions were characterized using many instrumental techniques to pinpoint the mesoporous nature and active sites of the catalysts. The proposed reaction mechanism has been well documented on the basis of catalytic results obtained for solvent-free oxidation of aromatics. Based on the catalytic results, we found that W-CPSA-SBA-15(0.2) is a very ecofriendly catalyst with exceptional catalytic activity.

Morpho-molecular and mating-type locus diversity of Ustilaginoidea virens: an incitant of false smut of rice from Southern parts of India.

AIMS: To characterize the geo-distinct isolates of Ustilaginoidea virens for morpho-molecular and mating-type locus diversity. METHODS AND RESULTS: Sixty-one isolates of U. virens collected from Southern India exhibited significant diversity in mycelial width (3·45-5·50 µm), colony colour (yellow, pale yellow, and white), and growth pattern (thick leather mat, raised-fluffy, flat-fluffy, and raised). Field-borne chlamydospores of each isolate were significantly smaller in size (3·34-5·26 µm2 ) compared to those formed on culture media (18·6-100·89 µm2 ). The phylogenetic study based on internal transcribed sequences revealed two clusters; however, most isolates (n = 54) were grouped in cluster-I, indicating common ancestral origin. We also identified 42 haplotypes; among them, Hap_3 has the highest number of isolates (n = 19). Mating-type locus (MAT1) analysis revealed all sixty-one isolates as heterothallic, wherein 37 and 24 isolates belonging to MAT1-1-1 and MAT1-2-1 heterothallic mating types, respectively. The microsynteny analysis of MAT1 loci of one of the Indian strain (Uv-Gvt) along with Uv-8b (China) strain revealed synteny conservation at MAT1 locus, which is flanked by conserved genes SLA2 and a hypothetical protein in the upstream and APN2, COX12 and APC5 in the downstream of the locus. CONCLUSIONS: Morpho-molecular study revealed the significant diversity among geo-distinct isolates, and MAT1 loci analysis indicated the distribution of heterothallic mating types in south Indian paddy fields. And also, complete synteny conservation between Indian and Chinese strain was observed at the MAT1 locus. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report describing the sexuality of Indian strains of the U. virens, which would help better understand the genetic diversity of the U. virens prevailing in Southern India and aid in developing resistant rice cultivars against this pathogen population.

New insight into the synthesis, morphological architectures and biomedical applications of elemental selenium nanostructures.

Selenium nanoparticles have been shown to be versatile in their applications by being used in catalysis, solar cells, electronic devices and especially in medical applications such as antiviral, anticancer, antitumor and antibacterial agents in different concentrations. They have also shown enhanced drug and gene delivery by conjugating with drug molecules and showing high synergistic effects. After realising their usefulness in the biomedical field, we have made a sincere effort to correlate and consolidate the recent developments made in their synthesis methods, structural features and biological applications. This review paper highlights the three preparation methods, being the chemical, physical and biological approaches. The variation in the different techniques employed for synthesis and the different parameters and process conditions dictating the size and morphology are discussed. The importance and influence of various reducing agents used in the chemical method, pulsed laser ablation technique in the physical method and green plant extract microorganism in the biological approach have been explored. The detailed structural features of trigonal crystalline structures, with different nanoscaled morphologies such as nano spheres, rods, wires, tubes and belts have also been explored. An overview of selenium nanoparticle activity in various biomedical applications such as anticancer, antioxidant, antiviral, antibacterial, antifungal, antiparasitic, and antidiabetics is discussed.

Genetic analysis of maydis leaf blight resistance in subtropical maize (Zea mays L.) germplasm.

Knowledge on the genetics of maydis leaf blight (MLB) is crucial to breed the resistant maize cultivars to combat disease epidemics as a sustainable and cost-effective approach. The present investigation was framed to understand the genetics of MLB resistance in subtropical maize. Two contrasting genotypes CM119 (susceptible) and SC-7-2-1-2-6-1 (resistant) were used to generate six genetic populations, namely P1, P2, F1, F2, BC1P1 and BC1P2, and evaluated in three target environments for MLB resistance under artificial epiphytotic condition. The CM119 and SC-7-2-1-2-6-1 showed susceptible and resistant reactions with mean disease reaction of 3.89-3.98 and 1.88-2.00, respectively. The derived generations, namely F1, F2, BC1P1 and BC1P2 showed mean disease reaction of 2.15-2.28, 2.44-2.51, 2.19-2.24 and 2.22-2.28, respectively in the test locations. The segregating generations (F2: 0.35-0.37; BC1P1: 0.24-0.29 and BC1P2: 0.17-0.20) showed variation for MLB disease resistance over the parental and first filial generations (P1: 0.11-0.17; P2: 0.08-0.13 and F1: 0.12-0.14). The genetic analysis of MLB resistance revealed the nonallelic interactions of duplicate epistasis type across the test locations. Among the gene interactions, dominance x dominance [l] effect was predominant over additive x additive [i] and additive x dominance [j] effects. The segregation analysis and the prediction of the number of major loci revealed at least two major genes associated with MLB tolerance in subtropical maize. Our investigation paved the foundation for the improvement of subtropical maize germplasm of MLB resistance.

Probable horizontal transmission of SARS-CoV-2 in an asymptomatic neonate: A case report

Introduction: Preterm delivery is of considerable concern to clinicians and researchers being a leading cause of infant morbidity and mortality in the industrialized countries and also contributes to substantial complications among survivors. Sub-Saharan Africa, including Nigeria accounts for significant proportion of preterm births, with over million deaths due to complication of prematurity. Objectives: The study aimed to determine the prevalence and associated morbidities of preterm deliveries at the University of Maiduguri Teaching Hospital, Maiduguri, North-Eastern Nigeria. Patients and methods: This is a retrospective review of neonates delivered before 37 completed weeks of gestation and admitted into the Special Care Baby Unit (SCBU) of the University of Maiduguri Teaching Hospital, from 1st January 2008 to 31st December 2015. Results: There were 3435 admissions into the Special Care baby Unit (SCBU) during the 8 year period. Out of these 1129 were preterm babies giving a prevalence of 32.9%. Of the 1129 preterm babies managed in SCBU, 714 case records were retrieved and analyzed giving a retrieval rate of 63%. There were 372 (52.1%) males and 342 (47.9%) females; with the male to female ratio of 1:1.08. There were 17(2.3%) extreme low birth weight (1000-1499 g), 406 (56.9%) low birth weight (1500- 2499 g) babies. The range of admission weights was 700-2500g with mean of 1600±900g. Conclusion: The burden, complications and mortality from preterm newborns remain significant public health challenges to care givers in Nigeria

Genome Mining-Based Identification of Identical Multirepeat Sequences in Plasmodium falciparum Genome for Highly Sensitive Real-Time Quantitative PCR Assay and Its Application in Malaria Diagnosis.

Developing ultrasensitive methods capable of detecting submicroscopic parasitemia-a challenge that persists in low transmission areas, asymptomatic carriers, and patients showing recrudescence-is vital to achieving malaria eradication. Nucleic acid amplification techniques offer improved analytical sensitivity but are limited by the number of copies of the amplification targets. Herein, we perform a novel genome mining approach to identify a pair of identical multirepeat sequences (IMRSs) that constitute 170 and 123 copies in the Plasmodium falciparum genome and explore their potential as primers for PCR. Real-time quantitative PCR analyses have shown the ability of P. falciparum IMRSs to amplify as low as 2.54 fg of P. falciparum genomic DNA (approximately 0.1 parasite), with a striking 100-fold increase in detection limit when compared with P. falciparum 18S rRNA (251.4 fg; approximately 10 parasites). Validation with clinical samples from malaria-endemic regions has shown 6.70 ± 1.66 cycle better detection threshold in terms of Ct value for P. falciparum IMRSs, with approximately 100% sensitivity and specificity. Plasmodium falciparum IMRS assays are also capable of detecting submicroscopic infections in asymptomatic samples. To summarize, this approach of initiating amplification at multiple loci across the genome and generating more products with increased analytical sensitivity is different from classic approaches amplifying multicopy genes or tandem repeats. This can serve as a platform technology to develop advanced diagnostics for various pathogens.

Perovskite lanthanum aluminate nanoparticles applications in antimicrobial activity, adsorptive removal of Direct Blue 53 dye and fluoride.

In the present study, efficient adsorptive removal of fluoride and Direct Blue 53 (DB-53) dye solution on perovskite lanthanum aluminate (PLA) has been investigated. To characterize the prepared PLA with analytical techniques like FTIR, SEM, EDS, PXRD, PHZPC and BET. The influence of adsorbent dose (0.05-0.6) gL-1, pH (2-12), contact time (0-60 min) and initial adsorbate concentration (0-50 mg L-1) were studied on adsorption process. Mathematical modeling of kinetics and isotherms were computed using equations. The pseudo-second-order kinetic and Halsey isotherm equilibrium model are best fitted with experimentally computed data with R2 > 0.96. The value of free mean energy EDR per adsorbate molecule was 1.77 kJmol-1 (fluoride) and 1.86 kJmol-1 (DB-53) with an adsorption capacity 25.103 and 38.03 respectively, hence nature of adsorption suggested as physisorption process. The maximum Langmuir adsorption capacity of PLA was investigated to be 40.8 mgg-1 (fluoride) and 71.4 mgg-1 (DB-53). Present study PLA deficits efficient adsorbent for fluoride and DB-53 dye for ground and industrial wastewater. Further, the effect of in-vitro antimicrobial studies was carried out against six test microorganisms. PLA showed, a maximum antibacterial effect at MIC 63 µg mL-1 for Gram-negative bacteria: Pseudomonas aeruginosa (NCIM 5029) due to the interaction between the positively charged nanoparticle and negatively charged cell wall.

Rapid detection of Puccinia triticina causing leaf rust of wheat by PCR and loop mediated isothermal amplification.

Leaf rust of wheat caused by Puccinia triticina has significant impact on wheat production worldwide. Effective and quick detection methodologies are required to mitigate yield loss and time constraints associated with monitoring and management of leaf rust of wheat. In the present study, detection of P. triticina has been simplified by developing a rapid, reliable, efficient and visual colorimetric method i.e., loop mediated isothermal amplification of DNA (LAMP). Based on in silico analysis of P. triticina genome, PTS68, a simple sequence repeat was found highly specific to leaf rust fungus. A marker (PtRA68) was developed and its specificity was validated through PCR technique which gave a unique and sharp band of 919 bp in P. triticina pathotypes only. A novel gene amplification method LAMP which enables visual detection of pathogen by naked eye was developed for leaf rust pathogen. A set of six primers was designed from specific region of P. triticina and conditions were optimised to complete the observation process in 60 minutes at 65o C. The assay developed in the study could detect presence of P. triticina on wheat at 24 hpi (pre-symptomatic stage) which was much earlier than PCR without requiring thermal cycler. Sensitivity of LAMP assay developed in the study was 100 fg which was more sensitive than conventional PCR (50 pg) and equivalent to qPCR (100 fg). The protocol developed in the study was utilized for detection of leaf rust infected samples collected from different wheat fields. LAMP based colorimetric detection assay showed sky blue color in positive reaction and violet color in negative reaction after addition of 120 µM hydroxyl napthol blue (HNB) solution to reaction mixture. Similarly, 0.6 mg Ethidium bromide/ml was added to LAMP products, placed on transilluminator to witness full brightness in positive reaction and no such brightness could be seen in negative reaction mixture. Further, LAMP products spread in a ladder like banding pattern in gel electrophoresis. Our assay is significantly faster than the conventional methods used in the identification of P. triticina. The assay developed in the study shall be very much useful in the development of diagnostic kit for monitoring disease, creation of prediction model and efficient management of disease.

Asparagine requirement in Plasmodium berghei as a target to prevent malaria transmission and liver infections.

The proteins of Plasmodium, the malaria parasite, are strikingly rich in asparagine. Plasmodium depends primarily on host haemoglobin degradation for amino acids and has a rudimentary pathway for amino acid biosynthesis, but retains a gene encoding asparagine synthetase (AS). Here we show that deletion of AS in Plasmodium berghei (Pb) delays the asexual- and liver-stage development with substantial reduction in the formation of ookinetes, oocysts and sporozoites in mosquitoes. In the absence of asparagine synthesis, extracellular asparagine supports suboptimal survival of PbAS knockout (KO) parasites. Depletion of blood asparagine levels by treating PbASKO-infected mice with asparaginase completely prevents the development of liver stages, exflagellation of male gametocytes and the subsequent formation of sexual stages. In vivo supplementation of asparagine in mice restores the exflagellation of PbASKO parasites. Thus, the parasite life cycle has an absolute requirement for asparagine, which we propose could be targeted to prevent malaria transmission and liver infections.

Prenatal diagnosis of colpocephaly with absent corpus callosum.

Colpocephaly is a rare abnormality of the brain, described as persistence of primitive foetal configuration of lateral ventricles. It has been found in association with several abnormalities of the brain. Herein we report a case of colpocephaly with absent corpus callosum, confirmed antenatally with foetal MRI following diagnostic suspicion based on absent septum pellucidum at prenatal sonography.

CdSiO3:Pr³âº nanophosphor: synthesis, characterization and thermoluminescence studies.

A series of Pr(3+) (1-9 mol%) doped CdSiO(3) nanophosphors have been prepared for the first time by a low temperature solution combustion method using oxalyldihydrizide (ODH) as a fuel. The final product was characterized by Powder X-ray diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscopy (SEM), and UV-Vis spectroscopy. The average crystallite size was calculated using Debye-Scherrer's formula and Williamson-Hall (W-H) plots and found to be in the range 31-37 nm. The optical energy band gap (E(g)) of undoped for Pr(3+) doped samples were estimated from Tauc relation which varies from 5.15-5.36 eV. Thermoluminescence (TL) properties of Pr(3+) doped CdSiO(3) nanophosphor has been investigated using γ-irradiation in the dose range 1-6 kGy at a heating rate of 5 °C s(-1). The phosphor shows a well resolved glow peak at ∼171 °C along with shouldered peak at 223 °C in the higher temperature side. It is observed that TL intensity increase with increase of Pr(3+) concentration. Further, the TL intensity at 171 °C is found to be increase linearly with increase in γ-dose which is highly useful in radiation dosimetry. The kinetic parameters such as activation energy (E), frequency factor (s) and order of kinetics was estimated by Luschiks method and the results are discussed.

Combustion synthesis, structural characterization, thermo and photoluminescence studies of CdSiO3:Dy³âº nanophosphor.

CdSiO(3):Dy(3+) (1-9mol%) nanophosphors were prepared for the first time using the solution combustion method. The process of monoclinic phase formation was investigated by PXRD, TG-DTA and FTIR. The results show that the phase formation temperature of combustion-derived monoclinic CdSiO(3) is found to be lower as compared to the powders prepared by solid-state and sol-gel methods. It was observed that the average crystallite size calculated by Debye-Scherrer's formula and Williamson-Hall (W-H) plot are well comparable and was found to be in the range of 35-70 nm. Scanning electron micrographs indicate that there exist circular microcrystalline particles. It is observed that the optical energy gap is widened with the increase of Dy(3+) ion dopant. The photoluminescence (PL) spectra exhibit characteristic transitions of Dy(3+) due to (4)F(9/2)→(6)H(15/2) (blue) and (4)F(9/2)→(6)H(13/2) (yellow) regions. The thermoluminescence (TL) glow curve of CdSiO(3):Dy(3+) nano powder exposed to UV irradiation exhibited one main peak centered at 170°C. The intensity of the main peak increases up to the dose of 20 min then it decreases. The glow curves were analyzed by the glow peak shape method and the estimated trap parameters are discussed.