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Introduction: The adverse prognosis of heart failure (HF) correlates with both N-terminal pro-B-type natriuretic peptide (NT-proBNP) and ferritin. The contribution of an underlying inflammatory process in the pathogenesis of HF is not only evidenced by increased ferritin (acute phase reactant), but also a reduced haemoglobin (Hb) due to cytokine-mediated bone marrow suppression. However, it remains unknown if there is a linear relationship between NT-pro BNP with ferritin and Hb levels. Objective: To determine an association between very elevated levels of NT-proBNP (>10,000pg/ml) with Hb and ferritin in patients with HF. Methods: A retrospective, cross-sectional study to evaluate levels of ferritin and Hb among patients with very high NT-proBNP levels (>10,000pg/ml) treated at a district hospital serving a population of 500,000 people. Inclusion criteria: in-patient between October to December 2020, diagnosis of HF, NT-proBNP level >10,000 pg/ml, measured haemoglobin and ferritin level within 7 days of NT-proBNP measurement. Results: Forty-five patients met all of the inclusion criteria. Mean age 81 years ± 12 years. There was a positive correlation between NTproBNP with ferritin and a negative correlation between NT-proBNP and Hb. With NT-proBNP on the x-axis and Hb on the y-axis, the trend line equated y = -0.0003x + 124.88. With NT-proBNP on the x-axis and ferritin on the y-axis, the trend line equated y = 0.0043x + 311.6. Conclusion: With rising levels of NT-proBNP, Hb levels decrease and ferritin levels increase in a linear manner, simultaneously. Larger studies are required to confirm this observation and to investigate the clinical implications of these findings. [ABSTRACT FROM AUTHOR]

This article reports on the luminescence properties of rare earth (Dy3+ and Tm3+)ions doped SrGa2Si2O8 phosphor were studied. SrGa2Si2O8phosphors weresynthesizedby employing solid state reaction method.From the measured X-ray diffraction (XRD) pattern of the samplemonoclinic phase structure has been observed. Thermoluminescenceand Mechanoluminescence properties of the γ-ray irradiated samples have been studied. Photoluminescence spectra of Dy3+ activated SrGa2Si2O8phosphor has been measured with an excitation wavelength at 348 nm,and it shows two emission bands at 483 and 574 nm due to 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions respectively. Whereas the photoluminescence spectra of Tm3+ activated SrGa2Si2O8 phosphor has been measured with an excitation wavelength at 359 nm and it exhibits two emission bands at 454 and 472 nm due to 1D2 → 3F4 and1G4 → 3H6 transitions respectively. In thermoluminescence study, γ-irradiatedthermoluminescence glow curve of SrGa2Si2O8:Dy3+ phosphor shows two well defined peaks at 293 °C (peak1)and 170 °C (peak2) whereas thermoluminescence glow curve of SrGa2Si2O8:Tm3+ phosphor shows peaks at 292 °C (peak1) and 184 °C (peak2) indicating that two sets of traps are being activated within the particular temperature range and the trapping parameters associated with the prominent glow peaks of SrGa2Si2O8:Dy3+ and SrGa2Si2O8:Tm3+ are calculated using Chen's peak shape and initial rise method.From the Mechanoluminescence study, only one glow peak has been observed. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper reports on the BaSi6N8O:Eu3+phosphor were prepared via modified two steps solid state diffusion technique in open air atmosphere and material was quenched at 1200°C for four hours. Eu3+activated BaSi6N8O phosphor was characterized by XRD, which confirms the formation of the sample. From the Scanning electron microscope (SEM) images, the surface morphology of the sample has been studied. The photoluminescence (PL) spectra of BaSi6N8O:Eu3+phosphor exhibits two emission bands at 614 nm (5D0→7F2) and at 587 nm (5D0→7F1) with an excitation wavelength of 396 nm. From the FTIR spectrum, bonding of atoms to each other and vibrational motions of molecules has been studied. ML was studied by dropping a piston on irradiated sample. From the ML glow curves single peak has been observed. ML intensity increases with activator concentration. Optimum ML has been observed for the sample having 1mole % of Eu ions. [ABSTRACT FROM PUBLISHER]

Li3PO4 phosphors prepared by solid-state diffusion technique and lyoluminescence (LL) as well as mechanoluminescence (ML) studies are reported. Dy- and Tb-activated phosphors show dosimetric characteristics using LL and ML techniques. The energy levels and hence trapping and detrapping of charge carriers in the material can be studied using ML. Li3PO4 phosphor can be used in the dosimetric applications for ionizing radiation. By using the LL technique, the LL characteristics of Li3PO4 may be useful for high radiation doses. We also report a more detailed theoretical understanding of the mechanism of LL and ML. [ABSTRACT FROM AUTHOR]

ABSTRACT Li3PO4 phosphor was prepared using a modified solid-state diffusion technique. In this work, photoluminescence, lyoluminescence and mechanoluminescence studies were carried out in a Li3PO4 microcrystalline powder doped with different rare earths. In photoluminescence studies, characteristic emission of Ce and Eu was observed. The lyoluminescence glow curves of Li3PO4 microcrystals show that lyoluminescence intensity initially increases with time and then decreases exponentially. The decay time consists of two components for all masses. The dependence of decay time, especially the longer component, on mass has been investigated. Experiments on γ-irradiated crystals have proved that the light emission originates from the recombination of released F-centres with trapped holes (V2-centres) at the sulfuric acid-solid interface. Incorporation of bivalent alkali in solid lithium phosphate leads to an enhancement of lyoluminescence. A possible explanation for the experimental results has been attempted. The phosphor has a mechanoluminescence single glow peak. Mechanoluminescence intensity under various loading conditions was investigated. It is observed that mechanoluminescence intensity increases with increasing impurity concentration and increasing piston impact velocity. The results may be considered as only being of academic interest in solid-state materials. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT The temperature and mass dependence of lyoluminescence intensity of γ-irradiated colored potassium chloride powder have been studied using a photomultiplier tube connected to an x-y recorder. The peak lyoluminescence intensity increases with increasing amount of solute added up to 50 mg and then tends to saturate. The lyoluminescence (LL) glow curves with mass of KCl microcrystals show that initially the LL intensity increases with time and then decreases exponentially with time. The decay time consists of two components for all the masses. The dependence of decay time, especially the longer component on mass, has been investigated. The temperature dependence of LL intensity shows that initially the peak LL intensity increases with temperature up to 60°C, and then decreases with further increase in temperature. The decay time tends to decrease with increasing temperature. An explanation for the experimental results has been attempted. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A mechanically induced grating formed over a twisted fiber can increase the resonant bandwidth. The tunability and control of the resonant bandwidth is found to be dependent on the induced twist. The effective group indices of cladding modes increase with the twist-induced birefringence. The difference in group indices between the LP01 and the cladding modes LP11, LP12, and LP13 decreases as the fiber twist rate increases above 0.5 turns/cm. This results in bandwidth enhancement of the grating. This broadband mode converter, which has a wide tunability, is cost effective and insensitive to pressure-induced birefringence. The resonant bandwidth can be increased and tuned further by forming two gratings in series with a twist-free and twisted fiber portions. A coupling bandwidth of around 100 nm (< 3 db) is achieved in this dual grating technique. [ABSTRACT FROM AUTHOR]

The long-period fiber grating is mechanically induced over a twisted fiber and its characteristics are investigated. The amplitude as well as the wavelength shift of the resonance is studied in response to the applied twist and pressures. These resonances decrease in amplitude and shift to shorter wavelength side as the applied twist increases. The spectral responses of a grating assembly formed by two grating sections in series, one section with a twisted fiber and other with an untwisted fiber, are also investigated. Shearing stress and photo-elasticity causes the fiber to be circularly birefringent and the mechanically induced grating formed over the twisted fiber region causes the appearance of two resonances shifted away from the resonances of the untwisted grating section. At higher twist rates, resonant wavelength shift becomes insensitive to applied pressures, showing a reduction in the induced linear birefringence. The wavelength shift is almost symmetric with respect to the applied twist rate in clockwise and counterclockwise directions. [ABSTRACT FROM AUTHOR]

Electronic Speckle Pattern Interferometry (ESPI) is a powerful sensitive optical whole field technique for nondestructive evaluation (NDE) as well as structural testing. It permits measurement of deformations in the micron and sub-micron range, which are caused by very small stress applied to the specimen under test. ESPI can be used for the detection of defects even in cryogenic conditions and corrosive environments – a feature that gives it potential for application for the inspection of space vehicle components. In this paper the application of ESPI for defect detection is explored and demonstrated on a low-modulus material which is used as an insulator in solid rocket motor. A comparative speckle interferometry technique with an optical configuration for out-of-plane displacement has been used in the real-time mode. ESPI fringe patterns are generated by digital subtraction of the recorded speckle patterns of the test specimen under different loading conditions. The studies are carried out on specimens with different types of defects under different stress conditions. The defects are revealed as anomalies in the otherwise regular fringe pattern. Fringe analysis techniques used to detect and interpret the fringe anomalies are also presented. [ABSTRACT FROM AUTHOR]

Electronic Speckle Pattern Interferometry (ESPI) is a fast developing whole field optical technique widely used for measuring displacement components, their derivatives, surface roughness, shape and slope contours of surfaces etc. This non-contact and highly sensitive technique has developed into a powerful on line inspection tool for non-destructive evaluation. The salient feature of ESPI is its capability to display the correlation fringes in real time on a TV monitor without the need of photographic processing or optical filtering. From the very inception of its discovery in 1970s a number of optical configurations have been developed for accurate measurements and better optimisation of results in engineering and non-engineering metrology. This paper reviews the main developments in the field of Electronic Speckle Pattern Interferometry that have been published over the past 20–25 years. The paper is illustrated with different optical configurations and their applications such as displacement and slope measurements with extensive references. The ESPI experimental set-up and the results obtained by the authors for its engineering applications such as non-destructive evaluation of low modulus materials used for space vehicle components are presented. [ABSTRACT FROM AUTHOR]

In the present investigation, a Q-switched Nd:YAG laser is used to study the various aspects of diamond processing for fabricating integrated optic and UV optoelectronic devices. Diamond is a better choice of substrate compared to silicon and gallium arsenide for the fabrication of waveguides to perform operations such as modulation, switching, multiplexing, and filtering, particularly in the ultraviolet spectrum. The experimental setup of the present investigation consists of two Q-Switched Nd:YAG lasers capable of operating at wavelengths of 1064 nm and 532 nm. The diamond cutting is performed using these two wavelengths by making the “V”-shaped groove with various opening angle. The variation of material loss of diamond during cutting is noted for the two wavelengths. The cut surface morphology and elemental and structural analysis of graphite formed during processing in both cases are compared using scanning electron microscopy (SEM) and laser Raman spectroscopy. Both the Q-Switched Nd:YAG laser systems (at 1064 nm and 532 nm) show very good performance in terms of peak-to-peak output stability, minimal spot diameter, smaller divergence angle, higher peak power in Q-switched mode, and good fundamental TEM 00 mode quality for processing natural diamond stones. Less material loss and minimal micro cracks are achieved with wavelength 532 nm whereas a better diamond cut surface is achieved with processing at 1064 nm with minimum roughness. [ABSTRACT FROM AUTHOR]

In 2002 it became a statutory requirement for all general practitioners (GPs) to undergo annual appraisal and in 2006 doctors will need to be revalidated to maintain a licence to practise. The Chief Medical Officer is currently reviewing the revalidation process and its relation to appraisal. There is limited evidence from appraised GPs regarding their views on appraisal and its relationship to revalidation. The aim of this study was to use qualitative methods to investigate these issues by conducting 12 semi-structured interviews with appraised GPs.The study found that GPs believe the purpose of appraisal should be educational and developmental. The main benefits from the process were opportunities for reflection, and the identification of learning and practice developmental objectives leading to a personal development plan (PDP). There was less impact for GPs already actively participating in continuing professional development (CPD), or for those less actively involved in CPD and not receptive to the appraisal process. Some GPs found the appraisal had not been challenging enough. The main criticism was the unclear purpose of appraisal in relation to revalidation. GPs accepted revalidation was necessary, but felt appraisal should be a developmental process that was not robust enough for revalidation and should not be linked to it.The implications of the study are that appraisers may need to adopt a more standardised approach in their level of challenge, but one which is more specifically targeted to meet individual GPs' requirements. In addition, appraisal should remain as a formative process which only partly informs revalidation. [ABSTRACT FROM AUTHOR]

Raman and FTIR spectra of KMg[sub ⅓]Nb[sub 2/3]PO[sub 5] (KMNP) crystal are recorded. The observed bands are assigned mainly in terms of vibrations of NbO[sub 6] octahedra and PO[sub 4] tetrahedra. The NbO[sub 6] octahedra in the crystal are distorted. Corner shared octahedra are present in the KMNP structure. The intense ν[sub l] band at 890 cm[sup -1] in the Raman spectra indicates an ordering in the crystal. The TiO[sub 6] octahedra in KTP crystal are more distorted than those of NbO[sub 6] octahedra in KMNP. The presence of Mg ions disrupts Nb-O-Nb chains leading to a distortion of NbO[sub 6] octahedra different from that of TiO[sub 6]. The PO[sub 4] tetrahedra in the crystal are linearly distorted. No structural phase transition is observed in the crystal when temperature is lowered to 77 K. [ABSTRACT FROM AUTHOR]

Raman, FTIR spectra of Eu(BrO[sub 3])[sub 3] · 9H[sub 2]O and Tb(BrO[sub 3])[sub 3] · 9H[sub 2]O are recorded and analyzed. The observed bands are assigned on the basis of BrO[sup -][sub 3] and H[sub 2]O vibrations. Electronic transitions observed in the Raman spectra of Eu(BrO[sub 3])[sub 3] · 9H[sub 2]O are also investigated. In Tb(BrO[sub 3])[sub 3] · 9H[sub 2]O the symmetry of BrO[sup -][sub 3] anion is lowered from C[sub 3v] to C[sub s] due to distortion. The wavenumber value of the v[sub 1] mode of BrO[sup -][sub 3] anion is found to be decreased from that of free state and is due to hydrogen bonding in the crystal. The decrease in wavenumber values of stretching modes and the increase in wavenumber values of the bending modes of water molecules from free state values confirm that they form hydrogen bonds with oxygen atoms are bromate ions in agreement with the structural data. Further the spectral pattern of water molecules indicates the presence of hydrogen bonds of varying strengths. The electronic transitions observed in Eu(BrO[sub 3])[sub 3] · 9H[sub 2]O suggest that Eu[sup 3+] ions are situated in the crystal at sites having symmetry higher than C[sub 2] or C[sub 1]. [ABSTRACT FROM AUTHOR]

Raman and infrared spectra of starch samples from sweet potato and different varieties of cassava (tapioca) are reported. Three regions of the spectra, the OH stretching region (3560-3000cm), the CH stretching region (3000-2800cm) and the finger print region (1600-200cm), have been studied. The results are discussed in relation to the hydrogen bonding and the properties of starch samples. [ABSTRACT FROM AUTHOR]

The infrared and Raman spectra of three tetrametaphosphates M PO ( M = Fe, Ni, Zn) have been recorded and analysed. A factor group model has been used to interpret the spectra of FePO and NiPO. A free ion model could explain the ZnPO spectra. The frequencies have been assigned on the basis of characteristic vibrations of PO and P-O-P groups. The PO ion is found to have C symmetry in FePO and NiPO and C in ZnPO. The ion in FePO is more distorted than in the other two. [ABSTRACT FROM AUTHOR]

Examines epitaxial silicon orientations by ex situ spectroscopic ellipsometry. Analysis of the peak values of the real and imaginary parts of the dielectric function; Impact of the surface features with lateral scales on the dielectric spectra; Implication of the high dielectric function peaks for nanometer lateral-scale roughness.

Oxynitrides on (100) silicon grown in a N2O ambient have been 60Co gamma irradiated. The conductance technique has been used to show that irradiation under bias can produce lateral charge nonuniformities at the Si:SiO2 interface. The ratio of induced fast to slow interface state density was found to be roughly independent of bias and nitridation, suggesting a common origin for these two types of defects. [ABSTRACT FROM AUTHOR]