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Summary: 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. [ABSTRACT FROM AUTHOR]

Ge 2 Sb 2 Te 5 (GST), a phase change material, generally exhibits two-step crystallization (amorphous → fcc → hcp) to store and process data. The present study reports the crystallization behavior and bonding mechanism of Ga-doped GST thin films with thermal annealing. Ga doping results in the formation of Ga–Te bonds and shows no bonding with other host elements (Ge and Sb), which changes the bonding mechanism and leads to one-step crystallization (amorphous → fcc). The optical transmission contrast confirmed the thermal stabilization of the fcc phase with thermal annealing. These findings suggest that Ga doping into GST thin films has thermally stabilized the metastable fcc phase and suppressed the hcp phase, hence posing it as a potential candidate for phase change memory applications with fast processing speed and low power consumption. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We studied the effect of Si-ion irradiation on Ge 2 Sb 2 Te 5 (GST) thin films. Amorphous GST thin films were irradiated with 80 MeV Si 6 + ions and studied using XRD, FESEM and UV–Vis-NIR measurements. After irradiation, we observed a slight increase in the particle size and a decrease in the optical bandgap. No phase transition from amorphous to crystalline was observed. Calculations using SRIM software provided insight into the possible reasons for the observed effects of swift heavy ions on GST. These minute changes in optical and micro-structural properties suggested that GST thin films were quite stable and radiation tolerant under the effect of 80 MeV Si ion irradiation. [ABSTRACT FROM AUTHOR]

• Ag9+ heavy ions (120 MeV) are irradiated on pure and Ag doped Ge 2 Sb 2 Te 5 (GST) thin films. • Phase transition is observed with Ag9+ ion irradiation which crystallizes amorphous GST thin films at higher fluence. • Ag doping suppress crystallization in ion irradiated GST thin films. Structural and optical study of pure and Ag-doped Ge 2 Sb 2 Te 5 (GST) thin films after swift heavy ion irradiation, is presented. In the present work, we have used 120 MeV Ag9+ ions for irradiation using various ion fluence. Structural properties were investigated using XRD and Raman spectroscopy. Undoped films were found to crystallize at the highest fluence (1 × 10 13 ions/cm2). Ag doping is found to suppress crystallization. From UV-Vis-NIR spectra, a decrease in optical bandgap was observed due to ion irradiation on these films. Observed results are explained on the basis of crystal nuclei, which results in crystallization and observed structural changes. Changes in defect chemistry are proposed to be responsible for the observed optical changes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composition Ge 2 Sb 2 Te 5 is widely studied for its application in memory devices. • 10% Ga doped in Ge 2 Sb 2 Te 5 thin film is noted to improve its properties further. • Nearly same optical contrast in amorphous to fcc phase and amorphous to hcp phase. • Thermal stabilization of fcc phase with annealing of (Ge 2 Sb 2 Te 5) 90 Ga 10 thin film. • Findings on ((Ge 2 Sb 2 Te 5) 90 Ga 10 thin film, supported the suppression of hcp phase. Owing to data storage ability of chalcogenide based Ge 2 Sb 2 Te 5 phase change alloy, this composition has been tremendously explored for its application in memory devices. Upon annealing, this composition exhibit two step crystallization, i.e, amorphous -to- fcc , and then from fcc -to- hcp phase. To address the issue of power consumption in such phase transitions, the present study is reporting one-step crystallization in (Ge 2 Sb 2 Te 5) 90 Ga 10 thin film, i.e. , from amorphous -to- fcc phase which is confirmed by optical transmission contrast studies. Thus, the results poses the promising data storage applicability of (Ge 2 Sb 2 Te 5) 90 Ga 10 thin film in phase change memory devices. [ABSTRACT FROM AUTHOR]

This work presents the influence of host defect centers on the photoluminescence characteristics of Mg 1 − x Er x Al 2 O 4 (x = 0.005, 0.01, and 0.03) nanocrystals under UV and near-infrared (NIR) excitations. The spinel-structured nanocrystals are synthesized through the combustion method. The Rietveld refinement and nuclear magnetic resonance analyses estimated the Er 3 + ion occupancy at octahedral and other random sites of the MgAl 2 O 4 lattice, and the existence of various lattice defects. Diffuse reflectance spectra showed broad bands attributed to oxygen vacancies as well as antisite defects and sharp peaks attributed to f–f transitions of Er 3 + ions. The upconversion luminescence spectra consisted of sharp emission lines, ascribed to Er 3 + ions, in the green and red wavelength regions, which overlapped over the broad curve attributed to intrinsic defects. Further, the UV excited downconversion luminescence spectra showed two broad emission bands in blue–violet and red-NIR regions with a very weak Er 3 + ion emission feature. This up- and downconversion emission revealed energy transfer between host and Er 3 + ions via intrinsic defects. As a result, the emission color changes from bluish purple to white by varying the excitation wavelength from UV to NIR. This rare earth activated luminescence from MgAl 2 O 4 nanocrystals would exhibit potential applications in display devices and solid-state lighting. [ABSTRACT FROM AUTHOR]

Objective To compare the duration of positive pressure ventilation (PPV) during delivery room resuscitation in neonates resuscitated with self-inflating bag (SIB) and T-piece resuscitator (TPR). Design Randomized control trial. Setting Delivery room and neonatal intensive care unit of a tertiary care center in northern India. Patients Consecutively born neonates more than 26 weeks of gestation requiring PPV at birth. Intervention Eligible neonates were randomized to two groups, SIB and TPR. Outcome measures Duration of PPV, intubation rates in delivery room, incidence of respiratory distress, need for mechanical ventilation during first 48 h and its duration, need for surfactant replacement therapy and mortality during NICU stay. Results Fifty neonates received PPV with a SIB and 40 received PPV with a TPR. The mean (SD) birth weight and gestational age of neonates in SIB and TPR groups were 2264 (872) and 2065 (814) g; 35.1 (3.6) and 34.3 (3.7) weeks, respectively. The median (IQR) duration of PPV in delivery room was significantly less in TPR group as compared to SIB; 30 (30–60) s vs. 60 (30–90) s, respectively; ( p < 0.001). A higher proportion of neonates required delivery room intubation in SIB group as compared to TPR group (34% vs. 15%, p = 0.04). In the TPR group, a higher proportion of neonates could be resuscitated with room air only (72.5% vs. 38%, p = 0.001). Other outcomes were comparable in the two groups. Similar findings were observed in neonates <34 weeks, except that fewer neonates resuscitated with TPR required invasive ventilation (31.6% vs. 77.8%, p = 0.008). Conclusion Use of TPR during delivery room resuscitation resulted in shorter duration of PPV and lesser rates of intubation as compared to SIB. More infants in this group could be resuscitated with room air only (CTRI/2010/091/002946). [ABSTRACT FROM AUTHOR]

Abstract: An environment friendly, inexpensive solvothermal route is used to synthesize polycrystalline Zn x Sn1−x O2 (0.0≤ x ≤0.07) nanorods with nanoflower morphology without using any organic solvents, surfactant or any catalytic agent under low hydrothermal pressure. Scanning electron microscopy (SEM) equipped with energy-dispersive x-ray spectra depicts the formation of near stoichiometric Zn x Sn1−x O2 nanorods. SEM analysis reveals that Zn incorporation in SnO2 decreases the nanorod diameter from ~20nm to ~10nm. High-resolution x-ray diffraction analysis reveals the rutile structure for x ≤0.04 samples, while for x =0.07 a Zn2SnO4 phase is observed. Near edge x-ray absorption fine structure and x-ray photoemission spectroscopy indicate that Zn atoms have been substituted for Sn sites in SnO2 lattice without forming secondary phases and also create numerous oxygen vacancy in the structure. [Copyright &y& Elsevier]

Abstract: Amorphous In–Ga–Zn–O (a-IGZO) thin films (∼200nm thickness) were deposited by radio-frequency (RF) magnetron sputtering on silicon and glass substrates at various working pressures (0.67–2.67Pa) and a fixed oxygen-to-argon gas-flow ratio (O2/Ar=5%). The transparency of all of the films was more than 85% in the visible range. With increased working pressure, the surface morphology of the films, as observed under atomic force microscopy (AFM), became rough; the optical band gap, estimated by Tauc plot, increased, and the mobility and carrier concentrations, according to Hall measurement, decreased and increased, respectively. The resistivity of the films initially decreased (up to 2.00Pa working pressure) and then increased (at 2.67Pa). It is suggested that the electrical property changes were affected by the role of the oxygen vacancies, whether as effective donors or as scattering centers. [Copyright &y& Elsevier]

Abstract: This paper reports the effect of proton irradiation on the electrical properties of a-As2S3 in the temperature range of 323–418K and frequency range 0.1–100kHz. The variation of transport property is studied with proton irradiation dose (1×1013 ions/cm2 and 1×1015 ions/cm2). It has been observed that proton irradiation changes the dc conductivity (σ dc ), dc activation energy (ΔE dc ) and ac conductivity (σ ac (ω)). The σ dc and σ ac (ω) increases with dose of proton irradiation. The value of frequency exponent (s) decreases with the temperature and irradiation dose. These results are explained in terms of change in density of defect states in these glasses. [Copyright &y& Elsevier]

Abstract: Thin films of chemical composition Ge20Se80 and Ag6(Ge0.20Se0.80)94 are prepared by thermal evaporation technique. The optical properties of these thin films are determined by a method, based only on the transmission spectra at normal incidence, measured over the 400–2000nm spectral range. This useful optical method takes into consideration the non-uniform thickness of thermally evaporated thin films. The dispersion of refractive index is discussed in terms of the single-oscillator Wemple and DiDomenico model. The optical absorption edge is described using the non-direct transition model proposed by Tauc and the optical band gap is calculated from the absorption coefficient (α) by Tauc’s extrapolation procedure. It has been found that the value of refractive index (n) and oscillator strength (E d) increase while average energy gap (E 0) and decrease after Ag incorporation. The decrease of has been explained on the basis of difference on the binding energies of different bonds which are arising due to the incorporation of Ag into a-Ge20Se80 thin films. [Copyright &y& Elsevier]

Abstract: Se–Te alloys are an important system of chalcogenide glasses from application point of view. The incorporation of Sn additive alters the electrical properties of these alloys. The conductivity measurements have been done on the thin films of a-Se85−x Te15Sn x (x =0, 2, 4, 6 and 10at.%) deposited using vacuum evaporation technique. Both dark (σ d) and photoconductivity (σ ph) show a maximum for x =6at.% of Sn, which, decreases on further Sn addition to the binary Se–Te alloy. The dark activation energy (ΔE d) shows a minimum for x =2at.% of Sn, but increases on further Sn addition. There is a sharp decrease in photosensitivity (σ ph/σ d) on Sn addition to Se85Te15 alloy. The charge carrier concentration (n σ ) calculated with the help of dc conductivity measurements also show a maximum at x =6at.% of Sn. The results are explained on the basis of increase in the density of localized states present in the mobility gap on Sn incorporation. [Copyright &y& Elsevier]

Abstract: This paper reports the effect of Ag-doping on electrical properties of a-Sb2Se3 in the temperature range 230–340K and frequency range 5–100kHz. The variation of transport properties with thermal doping has been studied. Ag-doping produces two homogeneous phases in the sample, which are found to be voltage dependent in the temperature range studied and frequency dependent in lower frequency region (0.1–10kHz). Activation energy E g and C′ [= σ 0 exp (γ/k), where γ, is the temperature coefficient of the band gap] calculated from dc conductivity has been found to vary from (0.42±0.01)eV to (0.26±0.01)eV and (4.11±0.01)×10−5 to (2.90±0.02)×10−6 Ω−1 cm−1 respectively. Ag-doping can be used to make the sample useful in device applications. [Copyright &y& Elsevier]

The article presents a study on the optical properties of a-(Ge20Se80)0.96Ag0.04 thin films before and after proton irradiation. Optical parameters such as refractive index, absorption coefficient, oscillator strength, oscillator energy and optical gap have been calculated. It has been observed that the optical parameters change after the proton irradiations.

Abstract: Amorphous Hf–In–Zn–O (a-HIZO) thin films were grown by radio frequency (RF) magnetron sputtering in a mixed atmosphere of Ar and O2 at fixed 5mTorr working pressure. A 13% enhancement (blue shift) in band gap from 3.59eV to 4.06eV was obtained as O2/Ar flow ratio increased from 5% to 50%. a-HIZO films deposited at higher O2/Ar gas flow ratio were more resistive. Oxygen-incorporation-induced reduction of oxygen vacancies is suggested to explain the band gap and resistivity increase. [Copyright &y& Elsevier]

Solar energy is the extreme realistic solution to regularly growing energy crisis. Several solar energy conversion systems have been in harnessing into useful form of energy. The performance of solar energy devices depends on the properties of nanomaterial used for solar energy conversion. As the primary sources of energy are depleted increasingly and give rise to the energy and environmental crisis for humankind. Therefore, exploration of FeS2 pyrite nanostructures for energy and environment applications are carried out in this review. This review focuses on the synthesis, functionalization as well as applications of FeS2 nanomaterial. The shape and size control have been governed by the synthesis methods such as hydrothermal method, sulfidation, solvothermal method and hot injection method. All these methods are discussed in detail. The review involves overview of FeS2, also outlining the structure, basic magnetic, optical and transport properties. Then the comprehensive study regarding modification of FeS2 nanostructures is also illustrated. The well synthesized FeS2 nanomaterials have been used for basic building blocks of functional systems and their application in photovoltaics and photocatalysis is briefly reviewed. Lastly, various future strategies and trends in these research areas are outlined. [ABSTRACT FROM AUTHOR]

This paper reports enhancement in the specific capacitance of iron-doped manganese oxide ( MnO 2) films, potentiostatically deposited on stainless-steel substrates. The properties of deposited films were investigated through cyclic voltammetry and galvanostatic charge/discharge characteristics. The specific capacitance, as determined through cyclic voltammetry and galvanostatic charge/discharge characteristics, respectively, was found to be 248.79 and 277.5 F g - 1 for undoped films, whereas it exhibited an increase with doping and was found to be 449.61 and 487.5 F g - 1 , respectively, corresponding to a dopant concentration of 4 atomic percentage. The electrochemical impedance data were fitted with a modified Randles equivalent circuit to find series resistance, charge-transfer resistance, double-layer capacitance and ion diffusion. According to electrochemical impedance spectroscopy, the enhancement of ion diffusion was found to be the major cause for enhancement in capacitive performance of the films. [ABSTRACT FROM AUTHOR]

Distribution of Zn 2 + , Al 3 + , and Fe 3 + ions on tetrahedral and octahedral sites in Fe 3 + -doped ZnAl 2 O 4 nanocrystals is studied through detailed x-ray diffraction (XRD) analysis. Significant changes in the intensity ratio of (220), (311), (400), and (422) diffraction peaks upon Fe addition were perceived, whose correlation with lattice inversion, Fe 3 + ions distribution, and ionic vacancies is probed through simulations and Rietveld refinement. Fe 3 + ions were found to be occupying tetrahedral sites in increasing proportion with the doping concentration, leading to decreased spinel inversion. However, different orders of defects, viz., cation and anion vacancies were also found to be playing their part in the statistical distribution of cations on octahedral/tetrahedral interstices. Fe L 2 , 3 -edge x-ray absorption near edge structure spectroscopy indicated Fe 3 + ions being present on tetrahedral as well octahedral interstices and distortion in cation polyhedra, while O K-edge inferred formation of different orders of ionic vacancies upon Fe addition, thereby corroborating the results from XRD. The photoluminescence study illustrated the quenched emission intensity upon Fe doping, with almost no change in emission color, and signatures of tetrahedral/octahedral Fe 3 + occupancy in the lattice. Thus, this study highlights the variation in degrees of freedom associated with atomic arrangements in spinel ZnAl 2 O 4 lattice upon Fe 3 + addition. [ABSTRACT FROM AUTHOR]

We have investigated the influence of combustion fuels on radiative defects of MgAl 2 O 4 spinel. Monoethanolamine (MEA), glycine, and urea fuels were employed to synthesize three samples of MgAl 2 O 4 nanocrystals, choice consequence of which has been observed on cation inversion and various intrinsic defects. Synchrotron powder x-ray diffraction patterns were refined by the Rietveld method. All samples exhibited a spinel structure, with a minor secondary phase of MgO in the sample synthesized by urea fuel. 27 Al nuclear magnetic resonance (NMR) inferred the distribution of Al cations among tetrahedral and octahedral sites with structural distortion of interstices. Rietveld, NMR, and diffuse reflectance spectra analyses revealed the presence of antisite defects, cation, and anion vacancies, which may be anticipated to induce F(Mg) defect centers through charge compensation. An electron spin resonance (ESR) study was carried out to investigate the paramagnetic defect centers. Two prominent broad ESR signals, attributed to F + and V − defect centers, originated from the delocalization of paramagnetic spins and their interaction with nearby cations. Photoluminescence studies further confirmed the existence of F(Mg) defect centers, VO -related defects, and Mg Al ′ and V Mg ″ defects in all samples. It was found that the nature of the defects did not change, but the concentration of defects varied significantly with the type of fuel employed and excitation wavelength. The MgAl 2 O 4 samples synthesized using glycine, urea, and MEA fuels were found to be rich in F(Mg) defect centers, VO -related defects, and Mg Al ′ , V Mg ″ , V O -related defects, respectively. The tailoring of defect-assisted photoluminescence by varying fuel types in MgAl 2 O 4 spinel can be exploited in various luminescence applications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In the present paper, the structural, optical and electrical properties of nanocrystalline Zn x Te 100−x (x = 0, 5, 20, 30, 40, 50) thin films (average thickness ~ 350 nm), deposited by thermal evaporation, have been studied. The X-ray diffraction results revealed that single phase Zn x Te 100−x was obtained at x = 50. Fourier transform infrared spectra also revealed the formation of zinc blende phase at x = 50. Energy dispersive X-ray spectroscopy confirms the elemental composition. Field emission scanning electron micrographs confirmed the uniform deposition of all thin films. UV–Vis–NIR results revealed that the optical band gap, calculated by Tauc's plots, increases with increase in Zn content. This may be due to the alloying effect. Temperature dependent dark conductivity showed that conductivity is thermally activated process having single activation energy in the measured temperature range (300–375 K). The dark conductivity and activation energy decreased with increase in Zn content. The explanations of variation in the properties of ZnTe with increase in Zn percentage have been provided. [ABSTRACT FROM AUTHOR]

Thermoluminescence (TL) response of γ -irradiated Cr3+ doped MgAl2O4 nanocrystals is studied to investigate the impact of dopant ions on intrinsic defects and trap distribution. At low doping concentration, the broad TL glow curve has a dominant incomplete peak attributed to deep F+ centers around 673 K and contribution from shallow V M g , V A l , M g A l and A l M g trapping states in low temperature region. TL glow curve intensity and trap distribution is found to be influenced with increase in Cr doping concentration. Electron spin resonance spectra show the interaction of electron spins at paramagnetic F+/V− centers with isolated and paired Cr3+ ions with increase in Cr doping concentration. Cr3+ ions doped at octahedral sites are found to be perturbed by the presence of V M g , M g A l , A l M g etc defect centers and may cause the formation of Cr associated defect clusters at higher doping concentration. A trapping mechanism is proposed as per the TL response obtained upon γ -irradiation to comprehend the intertrap charge transfer among various shallow and deep trapping states. [ABSTRACT FROM AUTHOR]

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 MESSAGES What’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. [ABSTRACT FROM AUTHOR]

Electrical measurements are done on Se85−xTe15Inx (x = 0, 2, 4, 6 and 10 at%) thin films. The dark conductivity (σd) increases and the activation energy (ΔEd) decreases as the In concentration increases. The photoconductivity (σph) also increases with the increase in In concentration. The photosensitivity (σph/σd) decreases sharply after the In incorporation. The charge carrier concentration (nσ) is calculated with the help of dc conductivity measurements. The value of nσ increases as the In concentration increases. The results are explained on the basis of an increase in the density of localized states present in the mobility gap. [ABSTRACT FROM AUTHOR]

Mo-doped MnS thin film of ~ 100 nm thickness has been deposited using the thermal evaporation technique. Structural and morphological properties have been determined. Temperature-dependent electrical properties have been studied under vacuum conditions in the temperature range 173–423 K. Electrical analysis inferred that the fabricated device follows two types of conduction mechanisms, i.e. thermally activated mechanism (251–423 K) with two activation energies (Ea1 ‒ 0.203 eV and Ea2 ‒ 2.214 eV) and variable range hopping (VRH) conduction mechanism (173–243) K. Light on–off cycles shows the switching action and dependence of the device on the incident light intensity. Light intensity-dependent photodetection properties revealed that current increased with an increase in incident light power density, following the power law with γ equal to ~ 2.12. Present work shows that Mo-doped MnS-based fabricated devices possess photoresponsivity (~ 45 mA/W) as well as detectivity (~ 40.5 × 109 Jones). [ABSTRACT FROM AUTHOR]

Thin-film of Mn-doped iron disulfide (FeS 2) has been prepared using the thermal evaporation method. This work reports the Hall measurements, temperature and light intensity-dependent photoconductivity, electrical transport mechanism, and photodetection properties of Mn-doped FeS 2 thin film. The transient photoconductivity measurements of p-type Mn-doped FeS 2 thin film show a consistent dependence upon temperature and light intensity. Charge transport mechanism was illustrated using different models. In region-I (303–393 ​K) deposited film followed the thermally activated transport mechanism. Nearest neighbour hopping (NNH) transport mechanism was followed by region-II (274–293 ​K), and Mott's variable range hopping (VRH) mechanism was dominant in region-III (108–273 ​K). The fabricated device resulted in higher photoconductivity due to collecting charge carriers through electrodes under light illumination. The results also revealed that Mn-doped thin film possessed good photoresponsivity (∼19 ​mA/W) as well as photo-detectivity (∼3.4 ​× ​1012 Jones) due to the occupation of localized states formed by Mn-doping. Light intensity-dependent photodetection properties suggested the potential for real-time photodetection applications. [Display omitted] • Effect of temperature on electrical properties of Mn-doped FeS 2 thin films. • Detailed study of charge transport properties and photo response of deposited thin films. • The fabricated device possesses photoresponsivity (∼19 ​mA/W) as well as photo-detectivity (∼3.4 ​× ​1012 Jones). [ABSTRACT FROM AUTHOR]

Abstract: We present results concerning the thickness dependence of structural, morphological and optical properties of the Zn0.98Cu0.02O films deposited on glass substrates using radio frequency (RF) sputtering method. The microstructure and the chemical state of oxygen, copper and zinc in ZnO and Zn0.98Cu0.02O films were investigated by X-ray diffraction spectroscopy (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. The results indicate that Zn0.98Cu0.02O films are the wurtzite structure with strong c-axis orientation. Crystallinity of the films is closely related to the film thickness. With increasing film thickness, there are more surface (mainly nanopores) defects existing in the Zn0.98Cu0.02O films and surface roughness increases. XRD and XPS data show that the valence state of copper in the Zn0.98Cu0.02O films is Cu2+. The transparency of all films is more than 85% in the visible region. [Copyright &y& Elsevier]

Abstract: Electrical measurements have been carried out on a-Se85−x Te15Sb x (x =0, 2, 4, 6 and 10at.%) thin films. The dark conductivity (σ d), photoconductivity (σ ph) increase and activation energy (ΔE d) decreases as the concentration of Sb additive increases (upto 4at.%). Photosensitivity (σ ph/σ d) decreases sharply after Sb incorporation. The charge carrier concentration (n σ ) is calculated with the help of dc conductivity measurements and its value increases with Sb incorporation. A reverse in the trend takes place in all these parameters as the Sb concentration is further increased (>4at.%). The results are explained on the basis of increase in the density of localized states present in the mobility gap of Se–Te–Sb alloys. [Copyright &y& Elsevier]

This study reports host-controlled luminescence from 4f0 and 4f 1 Ce levels in SrZnO2, probed through x-ray absorption near edge and photoluminescence spectroscopies. O K-edge perceived the presence of Ce 4f states at the bottom of conduction band and 5d states merging with conduction band. Due to such an arrangement, a fast radiative emission (11.15 ns, average) is observed through charge transfer excitation from host to empty 4f0 Ce levels. Ce content is found to vary the site occupancy, which is then modifying the population of 4f0 and 4f 1 energy states by altering Ce–O bond covalency. This study proposes the Ce-doped SrZnO2 system as a potential system for scintillators and lighting materials. [ABSTRACT FROM AUTHOR]

Trap distribution in MgAl2O4 nanocrystals has been investigated by analyzing thermoluminescence (TL) glow curves upon UV-irradiation. To probe various defects and trap distribution with the growth of spinel phase and crystallinity, three different fuels viz. monoethanolamine (MEA), glycine and urea, were employed in the combustion synthesis and annealing was performed at 700 ∘C and 900 ∘C. MEA and glycine resulted in crystalline spinel phase in annealed samples, however, urea resulted in minor secondary phase of MgO with the spinel phase in pristine as well as annealed samples. The x-ray photoelectron spectroscopy informed the presence of minor concentration of C and N in addition to Mg, Al and O, which are expected to influence the various defects of MgAl2O4 samples. The TL glow curve broadening in pristine and 700 ∘C annealed samples inferred the presence of multiple closely distributed traps. Shallow traps were more populated with urea, while higher concentrations of deep traps were observed with MEA and glycine. Computerized glow curve deconvolution of the TL glow curves revealed various trapping parameters. The observed shallow and deep traps have been attributed to various electron and hole centres such as antisite defects, O− and F+ centres. The significant high temperature shift of glow curve maxima in 700 ∘C annealed samples, synthesized using MEA and glycine, might be due to the reorganization of the local energy levels with the growth of spinel phase. Quenching of TL intensity at 900 ∘C anticipated the defect annealing accompanied by clustering of existing defects. Electron spin resonance analysis probed the existence of F+, V− centres and the spin–spin interaction of electron/hole spins trapped at these centres with the nearby cations, and estimated the formation of paramagnetic defect clusters at 900 ∘C annealing. A schematic band model is proposed to illustrate the TL behaviour in MgAl2O4 nanocrystals. [ABSTRACT FROM AUTHOR]

Applicability of spinel compounds is mainly governed by cation distribution in them. In the presented study, thermally induced cation ordering is found to influence the emission color of Mg 2 + , Fe 3 + co-doped ZnAl 2 O 4 spinel. Cation distribution is monitored through Mg K-edge, Fe L 2 , 3 -edge, O K-edge X-ray absorption near edge structure spectroscopy and X-ray diffraction analysis using synchrotron radiation. Thermal treatment provided sufficient energy to Zn 2 + , Mg 2 + , Al 3 + and Fe 3 + cations to redistribute themselves on tetrahedral and octahedral sites, and reduce the octahedral distortion, thereby gaining stability. Reduced inversion accompanied by decrease in oxygen vacancies, while increase in tetrahedral and octahedral site vacancies contributed toward more intense blue emission band and quenched yellow band, changing the emission color from bluish-white to blue. Correlation derived between cation ordering and luminescence upon thermal treatment predict Mg 2 + , Fe 3 + co-doped ZnAl 2 O 4 nanophosphors to be useful in thermal sensing applications. [ABSTRACT FROM AUTHOR]

Boron nitride (BN) has encouraged researchers to use it in composite materials due to its different properties. BN-based nanocomposites have been synthesized using a modified chemical method. X-ray diffraction (XRD) results confirmed the formation of hexagonal-BN and nickel oxide (NiO) phases in samples. XRD analysis shows that samples are textured along (100) plane which distorts structure and leads to formation of defect states. The electron density difference between BN and NiO as well as textural growth are two main reasons for variation in diffraction peak intensities. Raman spectroscopic results also revealed that peak intensity and position shifts with increase in NiO content, due to the distortions induced by NiO incorporation confirming the presence of defect states. Field emission scanning electron microscopy (FESEM) results showed that morphology of synthesized nanocomposites varies with increase of NiO concentration. Ultra-violet (UV)-visible results revealed that the absorption edge is red-shifted with NiO content, consequently, the band-gap energy of composites get decreased. Distorted crystal structure and defect states are responsible for variation in structural, morphological as well as optical properties. Results suggested that the nanocomposites can be explored for photodetection as well as gas sensing applications. [ABSTRACT FROM AUTHOR]

Thermoluminescence (TL) analysis of gamma-irradiated SrZnO2:Dy nanophosphors elucidates the presence of various trapping centers in forbidden band. Raman and Fourier-transformed infrared spectra indicate effect on vibrational structure upon doping. Complex glow curves are obtained at varying gamma radiation doses, exhibiting glow features in low (50-180 °C) and high (220-400 °C) temperature regions. The deconvolution of glow curves indicates the presence of TL peaks at =100, 143, 202, 269, and 337 =C. The effect of Dy doping is observed as emergence of new glow feature at =143 °C. The substitution of trivalent Dy into SrZnO2 host having divalent cations is proposed to be creating Dy1þ X (X = Sr, Zn) electron traps and V²X- hole traps, along with hitherto existing intrinsic defects. The concentration quenching of TL signal is perceived at 3 mol% Dy doping, whereas comparing glow curves for all samples at saturation dose indicate quenching of low- and high-temperature glow features at different doping concentrations. The theoretical track interaction model and empirical three trap one recombination center (3T1R) model is used to explain former and latter effects, respectively. A schematic band model is proposed to predict the trap distribution upon Dy inclusion, responsible for observed TL in SrZnO2:Dy nanophosphors. [ABSTRACT FROM AUTHOR]

Composite materials possess superior properties than their constituents which opens a field for different functional application devices. In present work films of boron nitride, nickel oxide and boron nitride/nickel oxide nanocomposite has been deposited using the drop-casting method. The structural analysis confirmed BN and NiO phase formation and the presence of defect states in the deposited films. The morphological analysis also shows the change in the morphology with composite formation. Electrical results revealed that BN 60 /NiO 40 nanocomposite possesses more resistivity than BN in the presence of hydrogen gas. A model has been proposed to explain variation in the electrical properties. To calculate the variation in resistivity with the change in hydrogen gas concentration, a linear regression technique has been used. It is observed that all BN, BN 60 /NiO 40 , and NiO films show significant (p < 0.001) positive change in resistivity with the increase in gas concentration. The present work illustrates the possibility that these materials can be explored for hydrogen gas sensing purposes. [ABSTRACT FROM AUTHOR]