In vitro comparism of the extracellular secretion of inulosucrase enzyme in potential probiotic Escherichia coli 16 and BL-21

Escherichia coli 16 has potential probiotic properties including antimicrobial activity due to extracellular secretion of colicins E1/1a1b. Inulosucrase (InuJ) enzyme catalyses the polymerization of a fructose moiety of sucrose leading to the formation of fructooligosaccharides. The present investigation compared the activity of InuJ enzymes cloned into pMAL-p2ΔlacIQ a deletion vector and transformed into E. coli 16 and standard strain that is, E. coli BL21. Specific activities of InuJ enzyme were estimated in supernatant, periplasm and lysate. Specific activities of InuJ activity in cell lysate were similar in E. coli 16 and E. coli BL21 without induction of tac promoter with isopropyl thio-β-Dgalactoside (IPTG). InuJ activity is mainly present in the periplasm of E. coli BL21 whereas in E. coli 16, most of the activity is in the supernatant. Superantant of E. coli 16 strain also showed good antibacterial activity due to colicin E1/Ia1b. Colicin E1/1a1b transport system could allow extracellular secretion of InuJ proteins in probiotic E. coli 16.Key words: Colicin, extracellular, E. coli, fructooligosaccharide, inulosucrase, prebiotic, probiotic

Impact of mothers’ knowledge and support for sustaining exclusive breastfeeding

Background: Breast milk is the best milk for the baby. It is beneficial for the baby as well as the mother, family, and nation. In spite of an established fact, still, a very low percentage (44.2%) is implementing it. Objective: The objective of this study was to find out the knowledge, concerns, and difficulties in breastfeeding and the obstacles in the practicing breastfeeding. Materials and Methods: A cross-sectional study was done at pediatric clinics in Warangal. A total of 1010 lactating mothers who were presenting for regular check-ups were enrolled. After taking oral consent, mothers were interviewed through a predesigned questionnaire containing 50 questions on pre- and post-natal counseling received, and knowledge of exclusive breastfeeding, importance of skin-to-skin contact (SSC), and their educational status and hygiene. The entire session of interview was carried out in the optimum privacy to create a favorable environment of acquiring the data. Results: Of 1010 mothers enrolled, only 25.4% had received antenatal counseling, 15.8% had received postnatal counseling regarding exclusive breastfeeding, 56.4% followed exclusive breastfeeding (EBF), and SSC was maintained by only 2%, after delivery which played an important role in breastfeeding, p=0.000003 for antenatal counseling and EBF. Conclusion: More attention should be given in educating mothers when they conceive, regarding breastfeeding, its problems and skills, during their first visit to health-care professionals

PERFORMANCE ANALYSIS OF RATE OF INCREASING HEAT TRANSFER IN A COMPOSITE MATERIAL ON MICRO TUBES USING CFD

In the last two years, the calculations have been made for a tube whose measurement ranges from 50 to 500 μm. The normal match number in the outlet level of the gag current depends on the pipe width and reaches 1.16 to 1.25. The properties of the low-flow gas stream were detected in a straight pipe of a smaller scale. A smaller scale tube whose total sum of the air is pushed out so that electrons in motion do not push against any gas particle and can effectively move from one terminal to another. The cathodic bundle tubes, which include picture tubes and other video tubes, are the most commonly used miniaturized scale tubes. In this statement, the development of heat exchange research has been improved by the use of new types of heat exchange liquids called nanosubstance’s that have nanoparticles. The limited convective laminar flow of various types of nano liquids (TIC and MGO), for example (TIC and MGO), with various volume sections of 0.4 and 0.5 using water as a liquid base, has been investigated through CFD research. The micro tube (meter) with a width of 0.01 cm and a length of 20 cm is used in this test. This test covers the Reynolds number in the range 90 to 800. Heat investigates to determine the temperature and movement of the heat with different materials. Materials currently used for copper tubes on a small scale, replace with compound materials

Efficient organic-inorganic hybrid perovskite solar cells processed in air

Organic-inorganic hybrid perovskite solar cells with fluorine doped tin oxide/titanium dioxide/CH3NH3PbI3-xClx/poly(3-hexylthiophene)/silver were made in air with more than 50% humidity. The best devices showed an open circuit voltage of 640 mV, a short circuit current density of 18.85 mA cm-2, a fill factor of 0.407 and a power conversion efficiency of 5.67%. The devices showed external quantum efficiency varying from 60 to 80% over a wavelength region of 350 nm to 750 nm of the solar spectrum. The morphology of the perovskite was investigated using scanning electron microscopy and it was found to be porous in nature. This study provides insights into air-stability of perovskite solar cells

Spatial clustering of defect luminescence centers in Si-doped low resistivity Al0.82Ga0.18N

A series of Si-doped AlN-rich AlGaN layers with low resistivities was characterized by a combination of nanoscale imaging techniques. Utilizing the capability of scanning electron microscopy to reliably investigate the same sample area with different techniques, it was possible to determine the effect of doping concentration, defect distribution, and morphology on the luminescence properties of these layers. Cathodoluminescence shows that the dominant defect luminescence depends on the Si-doping concentration. For lower doped samples, the most intense peak was centered between 3.36 eV and 3.39 eV, while an additional, stronger peak appears at 3 eV for the highest doped sample. These peaks were attributed to the (VIII-ON)2− complex and the V3−III vacancy, respectively. Multimode imaging using cathodoluminescence, secondary electrons, electron channeling contrast, and atomic force microscopy demonstrates that the luminescence intensity of these peaks is not homogeneously distributed but shows a strong dependence on the topography and on the distribution of screw dislocations.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeBMBF, 13N12587, Photonische Plattformtechnologie zur ultrasensitiven und hochspezifischen biochemischen Sensorik auf Basis neuartiger UV-LEDs (UltraSens

Coincident electron channeling and cathodoluminescence studies of threading dislocations in GaN

We combine two scanning electron microscopy techniques to investigate the influence of dislocations on the light emission from nitride semiconductors. Combining electron channeling contrast imaging and cathodoluminescence imaging enables both the structural and luminescence properties of a sample to be investigated without structural damage to the sample. The electron channeling contrast image is very sensitive to distortions of the crystal lattice, resulting in individual threading dislocations appearing as spots with black–white contrast. Dislocations giving rise to nonradiative recombination are observed as black spots in the cathodoluminescence image. Comparison of the images from exactly the same micron-scale region of a sample demonstrates a one-to-one correlation between the presence of single threading dislocations and resolved dark spots in the cathodoluminescence image. In addition, we have also obtained an atomic force microscopy image from the same region of the sample, which confirms that both pure edge dislocations and those with a screw component (i.e., screw and mixed dislocations) act as nonradiative recombination centers for the Si-doped c-plane GaN thin film investigated

Electron channelling contrast imaging for III-nitride thin film structures

Electron channelling contrast imaging (ECCI) performed in a scanning electron microscope (SEM) is a rapid and non-destructive structural characterisation technique for imaging, identifying and quantifying extended defects in crystalline materials. In this review, we will demonstrate the application of ECCI to the characterisation of III-nitride semiconductor thin films grown on different substrates and with different crystal orientations. We will briefly describe the history and the theory behind electron channelling and the experimental setup and conditions required to perform ECCI. We will discuss the advantages of using ECCI; especially in combination with other SEM based techniques, such as cathodoluminescence imaging. The challenges in using ECCI are also briefly discussed

Cross-correlation based high resolution electron backscatter diffraction and electron channelling contrast imaging for strain mapping and dislocation distributions in InAlN thin films

We describe the development of cross-correlation based high resolution electron backscatter diffraction (HR-EBSD) and electron channelling contrast imaging (ECCI), in the scanning electron microscope (SEM), to quantitatively map the strain variation and lattice rotation and determine the density and identify dislocations in nitride semiconductor thin films. These techniques can provide quantitative, rapid, non-destructive analysis of the structural properties of materials with a spatial resolution of order of tens of nanometers. HR-EBSD has a sensitivity to changes of strain and rotation of the order of 10−4 and 0.01° respectively, while ECCI can be used to image single dislocations up to a dislocation density of order 1010 cm−2. In the present work, we report the application of the cross-correlation based HR-EBSD approach to determine the tilt, twist, elastic strain and the distribution and type of threading dislocations in InAlN/AlN/GaN high electron mobility transistor (HEMT) structures grown on two different substrates, namely SiC and sapphire. We describe our procedure to estimate the distribution of geometrically necessary dislocations (GND) based on Nye-Kroner analysis and compare them with the direct imaging of threading dislocations (TDs) by ECCI. Combining data from HR-EBSD and ECCI observations allowed the densities of pure edge, mixed and pure screw threading dislocations to be fully separated