747 research outputs found
Low Temperature Precursor Route for Highly Efficient Spherically Shaped LED-Phosphors M2Si5N8:Eu2+ (M = Eu, Sr, Ba)
The highly efficient nitridosilicate phosphors M2Si5N8 (M = Sr, Ba, Eu) for phosphor-converted pc-LEDs were synthesized at low temperatures using a novel precursor route involving metal amides M(NH2)2. These precursors have been synthesized by dissolution of the respective metals in supercritical ammonia at 150Β°C and 300 bar. The thermal behavior and decomposition process of the amides were investigated with temperature programmed powder X-ray diffractometry and thermoanalytical measurements (DTA/TG). These investigations rendered the amides as suitable intermediates for reaction with silicon diimide (Si(NH)2). Thus, the desired nitridosilicate phosphors were obtained at relatively low temperatures around 1150β1400Β°C which is approximately 300Β°C lower compared to common synthetic approaches starting from metals or oxides. The influence of the thermal treatment on the phosphor morphology has been studied extensively. The accessibility of spherical phosphor particles represents another striking feature of this route since it improves light extraction from the crystallites due to decreasing light guiding and decreasing re-absorption inside the phosphor particle. The synthesized luminescent materials M2Si5N8:Eu2+ (M = Sr, Ba) exhibit quantum efficiencies and emission band widths (FWHM 70β90 nm) comparable to standard phosphor powders. Employment of Eu(NH2)2 as dopant reagent for synthesis of Ba2Si5N8:Eu2+ proved favorable for the formation of spherical crystallites compared to doping with Eu metal, halides, or oxide
Influence of lactococcal surface properties on cell retention and distribution in cheese curd
During cheese manufacturing, on average 90% of the starter culture cells are believed to be entrapped in the curd, with the remainder lost in whey. This paper shows that plasmid-cured dairy strains of Lactococcus lactis show cell retention in the curd of 30-72%, whereas over-expression of pili on the lactococcal cell surface can increase cell retention to 99%. Exopolysaccharide production and cell clumping and chaining do not influence cell retention in cheese curd. L. lactis surface alteration also strongly affected the distribution of cells in the cheese matrix: clumping and over-expression of pili led to formation of large cell aggregates embedded in the protein matrix whereas exopolysaccharide expression resulted in cells being surrounding by small serum regions in the protein matrix of the cheese. These results suggest that surface properties of dairy starter cultures strongly determine retention and distribution of the bacteria in cheese curd. (C) 2018 The Authors. Published by Elsevier Ltd
The Randomized Shortened Dental Arch Study: Tooth Loss
The evidence concerning the management of shortened dental arch (SDA) cases is sparse. This multi-center study was aimed at generating data on outcomes and survival rates for two common treatments, removable dental prostheses (RDP) for molar replacement or no replacement (SDA). The hypothesis was that the treatments lead to different incidences of tooth loss. We included 215 patients with complete molar loss in one jaw. Molars were either replaced by RDP or not replaced, according to the SDA concept. First tooth loss after treatment was the primary outcome measure. This event occurred in 13 patients in the RDP group and nine patients in the SDA group. The respective Kaplan-Meier survival rates at 38 months were 0.83 (95% CI: 0.74-0.91) in the RDP group and 0.86 (95% CI: 0.78-0.95) in the SDA group, the difference being non-significant
Protein quality as a complementary functional unit in life cycle assessment (LCA)
Goal and theoretical commentary
A number of recent life cycle assessment (LCA) studies have concluded that animal-sourced foods should be restrictedβor even avoidedβwithin the human diet due to their relatively high environmental impacts (particularly those from ruminants) compared with other protein-rich foods (mainly protein-rich plant foods). From a nutritional point of view, however, issues such as broad nutrient bioavailability, amino acid balances, digestibility and even non-protein nutrient density (e.g., micronutrients) need to be accounted for before making such recommendations to the global population. This is especially important given the contribution of animal sourced foods to nutrient adequacy in the global South and vulnerable populations of high-income countries (e.g., children, women of reproductive age and elderly). Often, however, LCAs simplify this reality by using βproteinβ as a functional unit in their models and basing their analyses on generic nutritional requirements. Even if a βnutritional functional unitβ (nFU) is utilised, it is unlikely to consider the complexities of amino acid composition and subsequent protein accretion. The discussion herein focuses on nutritional LCA (nLCA), particularly on the usefulness of nFUs such as βprotein,β and whether protein quality should be considered when adopting the nutrient as an (n)FU. Further, a novel and informative case study is provided to demonstrate the strengths and weaknesses of protein-quality adjustment.
Case study methods
To complement current discussions, we present an exploratory virtual experiment to determine how Digestible Indispensable Amino Acid Scores (DIAAS) might play a role in nLCA development by correcting for amino acid quality and digestibility. DIAAS is a scoring mechanism which considers the limiting indispensable amino acids (IAAs) within an IAA balance of a given food (or meal) and provides a percentage contribution relative to recommended daily intakes for IAA and subsequent protein anabolism; for clarity, we focus only on single food items (4βΓβanimal-based products and 4βΓβplant-based products) in the current case exemplar. Further, we take beef as a sensitivity analysis example (which we particularly recommend when considering IAA complementarity at the meal-level) to elucidate how various cuts of the same intermediary product could affect the interpretation of nLCA results of the end-product(s).
Recommendations
First, we provide a list of suggestions which are intended to (a) assist with deciding whether protein-quality correction is necessary for a specific research question and (b) acknowledge additional uncertainties by providing mitigating opportunities to avoid misinterpretation (or worse, dis-interpretation) of protein-focused nLCA studies. We conclude that as relevant (primary) data availability from supply chain βgatekeepersβ (e.g., international agri-food distributors and processors) becomes more prevalent, detailed consideration of IAA provision of contrasting protein sources needs to be acknowledgedβideally quantitatively with DIAAS being one exampleβin nLCA studies utilising protein as a nFU. We also contend that future nLCA studies should discuss the complementarity of amino acid balances at the meal-level, as a minimum, rather than the product level when assessing protein metabolic responses of consumers. Additionally, a broader set of nutrients should ideally be included when evaluating βprotein-rich foodsβ which provide nutrients that extend beyond amino acids, which is of particular importance when exploring dietary-level nLCA
Prevalence of antibodies against influenza A and B viruses in children in Germany, 2008 to 2010
The prevalence of influenza A and B virus-specific IgG was determined in sera taken between 2008 and 2010 from 1,665 children aged 0-17 years and 400 blood donors in Germany. ELISA on the basis of whole virus antigens was applied. Nearly all children aged nine years and older had antibodies against influenza A. In contrast, 40% of children aged 0-4 years did not have any influenza A virus-specific IgG antibodies. Eighty-six percent of 0-6 year-olds, 47% of 7-12 year-olds and 20% of 13-17 year-olds were serologically naive to influenza B viruses. By the age of 18 years, influenza B seroprevalence reached approximately 90%. There were obvious regional differences in the seroprevalence of influenza B in Germany. In conclusion, seroprevalences of influenza A and influenza B increase gradually during childhood. The majority of children older than eight years have basal immunity to influenza A, while comparable immunity against influenza B is only acquired at the age of 18 years. Children aged 0-6 years, showing an overall seroprevalence of 67% for influenza A and of 14% for influenza B, are especially at risk for primary infections during influenza B seasons
ΠΠΈΠ½Π³Π²ΠΎΡΡΠΈΠ»ΠΈΡΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΠΎΡΠ³Π°Π½ΠΈΠ·Π°ΡΠΈΡ Π΄ΠΈΡΠΊΡΡΡΠΈΠ²Π½ΠΎΠΉ ΡΡΡΠ°ΡΠ΅Π³ΠΈΠΈ ΠΏΡΠΎΠ΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΡΠ½ΠΈΠ²Π΅ΡΡΠΈΡΠ΅ΡΠ° Π² ΡΠΎΠΏΠΎΡΡΠ°Π²ΠΈΡΠ΅Π»ΡΠ½ΠΎΠΌ Π°ΡΠΏΠ΅ΠΊΡΠ΅ (Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ Π°Π½Π°Π»ΠΈΠ·Π° ΡΠ°ΠΉΡΠΎΠ² ΡΠΎΡΡΠΈΠΉΡΠΊΠΎΠ³ΠΎ ΠΈ ΠΊΠΈΡΠ°ΠΉΡΠΊΠΎΠ³ΠΎ Π²ΡΠ·ΠΎΠ²)
ΠΠ±ΡΠ΅ΠΊΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ - ΡΠ½ΠΈΠ²Π΅ΡΡΠΈΡΠ΅ΡΡΠΊΠΈΠΉ Π΄ΠΈΡΠΊΡΡΡ.
Π¦Π΅Π»Ρ ΡΠ°Π±ΠΎΡΡ β Π²ΡΡΠ²Π»Π΅Π½ΠΈΠ΅ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠ΅ΠΉ Π»ΠΈΠ½Π³Π²ΠΎΡΡΠΈΠ»ΠΈΡΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΎΡΠ³Π°Π½ΠΈΠ·Π°ΡΠΈΠΈ Π΄ΠΈΡΠΊΡΡΡΠΈΠ²Π½ΠΎΠΉ ΡΡΡΠ°ΡΠ΅Π³ΠΈΠΈ ΠΏΡΠΎΠ΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ Π½Π° ΡΠ°ΠΉΡΠ°Ρ
Π²ΡΠ·ΠΎΠ² Π Π€ ΠΈ ΠΠΠ .
Π ΠΏΡΠΎΡΠ΅ΡΡΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈΡΡ Π΄ΠΈΡΠΊΡΡΡΠΈΠ²Π½ΡΠΉ, Π»ΠΈΠ½Π³Π²ΠΈΡΡΠΈΡΠ΅ΡΠΊΠΈΠΉ, ΡΡΠΈΠ»ΠΈΡΡΠΈΡΠ΅ΡΠΊΠΈΠΉ, ΡΠΎΠΏΠΎΡΡΠ°Π²ΠΈΡΠ΅Π»ΡΠ½ΡΠΉ Π°Π½Π°Π»ΠΈΠ· ΠΊΠΎΠΌΠΌΡΠ½ΠΈΠΊΠ°ΡΠΈΠ²Π½ΠΎΠΉ ΡΡΡΠ°ΡΠ΅Π³ΠΈΠΈ ΠΏΡΠΎΠ΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ Π²ΡΠ·ΠΎΠ².
Π ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ Π±ΡΠ»ΠΈ Π²ΡΡΠ²Π»Π΅Π½Ρ Π»ΠΈΠ½Π³Π²ΠΈΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈ ΡΡΠΈΠ»ΠΈΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ ΠΎΡΠΎΡΠΌΠ»Π΅Π½ΠΈΡ ΠΆΠ°Π½ΡΠΎΠ² ΡΠ°ΠΉΡΠΎΠ² Π²ΡΠ·ΠΎΠ², ΡΠ΅Π°Π»ΠΈΠ·ΡΡΡΠΈΡ
ΡΡΡΠ°ΡΠ΅Π³ΠΈΡ ΠΏΡΠΎΠ΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ, ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ ΡΠΎΠΏΠΎΡΡΠ°Π²ΠΈΡΠ΅Π»ΡΠ½ΡΠΉ Π°Π½Π°Π»ΠΈΠ·, Π²ΡΡΠ°Π±ΠΎΡΠ°Π½Ρ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΠΈ ΠΏΠΎ ΠΏΠ΅ΡΠ΅Π²ΠΎΠ΄Ρ.
ΠΠ±Π»Π°ΡΡΡ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ: ΠΏΠ΅ΡΠ΅Π²ΠΎΠ΄ΡΠ΅ΡΠΊΠ°Ρ ΠΏΡΠ°ΠΊΡΠΈΠΊΠ° ΠΏΠ΅ΡΠ΅Π²ΠΎΠ΄ΠΎΠ² ΠΈ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠΊΠΈ Π²Π½Π΅ΡΠ½ΠΈΡ
Π²Π΅ΡΡΠΈΠΉ ΡΠ°ΠΉΡΠΎΠ² Π²ΡΠ·ΠΎΠ².
ΠΠΊΠΎΠ½ΠΎΠΌΠΈΡΠ΅ΡΠΊΠ°Ρ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ/Π·Π½Π°ΡΠΈΠΌΠΎΡΡΡ ΡΠ°Π±ΠΎΡΡ Π·Π°ΠΊΠ»ΡΡΠ°Π΅ΡΡΡ Π² ΠΏΡΠ΅Π΄ΠΎΡΡΠ°Π²Π»Π΅Π½ΠΈΠΈ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΠΉ ΠΏΠΎ ΠΏΠ΅ΡΠ΅Π²ΠΎΠ΄Ρ ΡΠ°ΠΉΡΠΎΠ² Π² Π°ΡΠΏΠ΅ΠΊΡΠ΅ ΠΏΡΠΎΠ΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ Π²ΡΠ·Π°.Object of research: university discourse.
Aim of research is to determine linguistic and stylistic features of promotion as a discourse strategy conducted on websites of Russian and Chinese universities.
The following activities were carried out inn the course of the research: discourse analysis, linguistic, stylistic and comparative analysis of the communication strategy of universities promotion.
Research results: linguistic and stylistic features of universities websites genres that use communication strategy of promotion were determined, comparative analysis was carried out, translation recommendations were provided.
Appliance scope: translational practice of translation and design of universities foreign language versions
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