bluuebunny/crossref_metadata_2025 huggingface dataset:
Why Managers Do Not Seek Voice from Employees: The Importance of Managers’ Personal Control and Long-Term Orientation
Authors: Sherf Elad N. , Tangirala Subrahmaniam , Venkataramani Vijaya
Published: April 2019

Voice, or employees’ upward expression of challenging but constructive concerns or ideas on work-related issues, can play a critical role in improving organizational effectiveness. Despite its importance, evidence suggests that many managers are often hesitant to solicit voice from their employees. We develop and test a new theory that seeks to explain this puzzling reluctance. Voice is a distinctive behavior that involves escalation of opinions, ideas, or concerns by employees to their managers with the expectation that they would respond by making systemic changes in their teams. Hence, we argue that managers are likely to solicit voice more when they perceive requisite discretion and influence (personal control) to effect changes in their teams. Additionally, because voice-driven change can cause short-term disruptions and bring about benefits typically only over time, we propose that managers act on their personal control to solicit more voice when they also possess adequate long-term orientation. We find support for our arguments across four studies using experimental as well as correlational methods. We discuss the conceptual and practical implications of our findings.
The specific challenges of adopted children
Authors: Martindale Darren
Published: April 2019

Previously looked after children can present particular challenges and schools are required to have a ‘designated teacher’ in place. Darren Martindale offers us best practice advice
Everyone on board…
Authors: Hindley Bethan
Published: April 2019

When planning your whole-school CPD programmes, it is vital that staff are on board. Bethan Hindley looks at five tenets of change management and achieving staff CPD buy-in
Getting Appraisal Right
Authors: Burnage Steve
Published: April 2019

In this regular article, Steve Burnage talks us through CPD workshop ideas that can be adapted for your school. This time he looks at how to get appraisal practices right
Effect of Pallet Size Modified Atmosphere Packaging Using Polyamide Film and Linear Low Density Polyethylene Film on the Shelf Life of Strawberries
Authors: Kim Jinse , Jung Hyun Kyung , Nam So Young , Son Jae Yong , Park Seok Ho , Choi Dong Soo , Kim Yong Hoon , Lee Soo Jang , Park Chun Wan
Published: April 2019

For the vessel export of strawberries, modified atmosphere package (MAP) using polyamide (PA) film and linear low density polyethylene (LLDPE) film was investigated to extend the shelf life of strawberries. Because the temperature and relative humidity changes of the MAP were lower than the changes of the control, the weight loss of the MAP were lower than that of the control. The low oxygen level and high carbon dioxide level were effective to decrease the fungal decay rate and to increase the hardness of strawberries. The Hunter’s color differences before and after storage showed no distinct difference between the MAP and the control. The lightness had a tendency to decrease while the redness increased. There were no significant changes of the soluble solids during the storage. The shelf life of strawberries could be extended to 16 days using the MAP considering the weight loss and the fungal decay rate. Thus, this MAP method using PA film and LLDPE film was effective to extend the shelf life of strawberries.
Hitzaurrea
Authors: Lamikiz Aitzol , López de Lacalle Luis Norbeto
Published: April 2019

Makina-erremintari buruzko Ale bereziaren hizaurrea
Egyetemi tanulmányaikat megkezdő hallgatók tanulási mintázata és tanulói profilja
Authors: D. Molnár Éva , Gál Zita
Published: April 2019

Nagy felelősség új Nemzeti Alaptantervet készíteni. Nem változik meg tőle egészen a magyar iskolaügy, de azért nagy a hatása, s az oktatás minden szereplőjének munkájára hatással van. Ezért nagy a felelőssége annak is, aki egy, a Nemzeti Alaptantervről szóló vitához hozzászól, aki véleményét, elképzeléseit érvényesíteni akarja. Nem is egyetlen szakma belügye az alaptanterv tartalma, hanem sok egymásra épülő vagy egymástól külön-külön fejlődő és vizsgáló diszciplína előmunkálatainak közös eredője lehet a majdani végeredmény. Tanulmányomban már csak ezért is nemcsak az irodalomtudomány tudására hivatkozom, de különböző szociológiai, pedagógiai, didaktikai, oktatáskutatási, olvasáskutatási eredményekre is. Mert miképp a vizsgált és befolyásolni kívánt jelenség – nevezetesen az iskolaügy – rendkívül összetett, úgy vizsgálata is szükségképpen ilyen kell legyen, s amikor egy hozzászólás az iskolarendszer egy szegmensének jogi eszközökkel történő módosítására, befolyásolására vagy megváltoztatására kíván érveket felhozni, akkor bizony mindezen aspektusok közül minél többre kell, hogy a figyelme kiterjedjen.
Flame Propagation Model and Combustion Phenomena: Observations, Characteristics, Investigations, Technical Indicators, and Mechanisms
Authors: Aljerf Loai , AlMasri Nuha
Published: April 2019

Critical conditions are usually obtained for ignition in a self-heating solid system consisting of two components generating heat independently, one component being inexhaustible and the other exhaustible by either simple first order or autocatalytic reaction. Ignition depends upon whether the exhaustible component can cause a temperature rise in excess of the upper stationary, but unstable, value possible for the inexhaustible component reacting alone. The system provides a theoretical model for some commonly occurring examples of self-heating and ignition in porous solids containing oxidisable oils. It is shown that: (a) the ignition criterion of the model, which involves a nonarbitrary critical temperature increase, has a high degree of physical reality; (b) the model is, in principle, capable of predicting ignition from primary kinetic and thermal data; (c) it is likely to be possible often to make a reliable prediction of critical size for self-ignition in a two-component system at ordinary atmospheric temperatures by a simple extrapolation from small-scale ignition data, obtained at higher temperatures, in the same way as for ignition due to a single reaction. Examination of both adiabatic and non-adiabatic flame theories showed that a 'steady state' exists only under the special condition that a heat sink exists at the initial temperature. For the general case of freely propagating, non-adiabatic flames only a quasi-steady state can be achieved.
Das an Electric Current have an Acoustic Component?
Authors: Berezin A.A.
Published: April 2019

The quantum model of electric current suggested by Feynman has been enlarged by n difference-differential Hamiltonian equations describing the phonon dynamics in one dimensional crystallyne lattice. The process of interaction between the electron and phonon components in a crystalline lattice of a conductor has been described by 2n parametrically coupled difference-differential Hamiltonian equations. Computer analysis of the system of these coupled equations showed that their solutions represent a form of the quantum recurrence similar to the Fermi-Pasta-Ulam recurrence. The results of the research might reconsider the existing concept of electric current and will be possibly helpful in developing an acoustic «laser».
Continuing Medical Education Questions: April 2019
Authors: Bull-Henry Kathy
Published: April 2019

Article Title: The Clinician's Guide to Suspected Small Bowel Bleeding
Vom Anfangen
Authors: Sansour Teresa , Bauernschmitt Susanne
Published: April 2019

Teresa Sansour und Susanne Bauernschmitt stellen ausgehend von einem inklusiven Praxisprojekt an der Hochschule verschiedene künstlerische Impulssetzungen und methodische Einstiegsszenarien der bildenden Kunst vor, die Ausgangspunkte und Anstöße für selbstbestimmte künstlerische Gestaltungswege sein können. Daran anknüpfend wird an exemplarischen Projektverläufen aufgezeigt, wie diese gemeinsamen künstlerischen Anfangsszenarien - im Sinne einer Subjektorientierung und Differenzierung - in individuelle Gestaltungsprozesse überführt werden können.
Die Kultur-Kiste
Authors: Christ Markus
Published: April 2019

Markus Christ wählt einen handlungstheoretischen Ansatz, um anhand der vielfältigen Eigenschaften von Kisten einen niederschwelligen und sehr vielschichtigen Zugang zur performativen künstlerischen Tätigkeit aufzuzeigen. Die Reflexion der Inszenierung von Persönlichem im sozialen Raum spielt hier ebenso eine Rolle wie das grundsätzlichere Thema der Teilhabe an gesellschaftlichen Vorgängen.
Wenn die Kreativität an ihre Grenze kommt
Authors: Witte Katharina
Published: April 2019

Katharina Witte zeigt in ihrem Beitrag anhand von exemplarischen Beispielepisoden auf, dass kreative Prozesse in der künstlerischen Arbeit mit Menschen mit unterschiedlichen Voraussetzungen auf mehreren Ebenen stattfinden. Auf diese Weise können auch vielfältige ästhetische Ausdrucksformen entstehen, an denen alle Mitwirkenden auf die ihnen angemessene Weise beteiligt sind.
Globale Neuordnung durch antikoloniale Konferenzen
Authors: Ghirmai Philmon
Published: April 2019

Die bisherige Historiographie zur afrikanischen Dekolonisation hat häufig entscheidende Süd-Süd-Beziehungen übersehen. Philmon Ghirmais Untersuchung nimmt daher antikoloniale Konferenzen und internationale Organisationen in den Blick, die in den 1950er- und 1960er-Jahren in Ghana und Ägypten stattgefunden haben bzw. dort ihren Sitz hatten. Anhand von breitem Archivmaterial aus afrikanischen - aber auch europäischen - Ländern zeichnet die Studie nach, wie afrikanische Politiker und Aktivisten aus Kolonien und bereits unabhängigen Ländern zusammentrafen, Verbindungen knüpften und gemeinsam Wege in die Unabhängigkeit sowie transnationale postkoloniale Ordnungsvorstellungen entwickelten.
Spettacolo
Authors: Kreutzer Tanja
Published: April 2019

Die Zweitausgabe von Giorgio Vasaris »Viten« von 1568 ist um umfangreiche Schilderungen zu religiösen und profanen Festen sowie zu den damit verbundenen theatralen Aufführungsformen und ihrer Ausstattung ergänzt. Erstmalig analysiert Tanja Kreutzer diese Passagen im Hinblick auf die ihnen zugrundeliegenden kunsttheoretischen und historiografischen Argumentationsmuster. Im Abgleich mit der zeitgenössischen Tanz-, Theater- und Musiktheorie sowie mit Städtelob, Stadtgeschichtsschreibung und Biografik wird die essentielle Rolle des Ephemeren für die Geschichtserzählung der zweiten Vitenfassung belegt - als Paradebeispiel für ein breites Diffundieren der Künste auf ihrem Höchststand und mögliche Perspektive für den Fortgang der Kunstentwicklung nach Michelangelos Tod.
Cultural Governance in Österreich
Authors: Schad Anke Simone
Published: April 2019

Wie kann Kulturpolitik so gestaltet werden, dass - im Sinne einer Cultural Governance - nicht nur Politik und nachgeordnet Verwaltung in Entscheidungsprozesse einbezogen sind, sondern auch die Betroffenen: Künstler_innen, Kulturschaffende, Bürger_innen? Welche Allianzen und Konflikte entstehen in Verhandlungssituationen? Und wie argumentieren Vertreter_innen von Politik, Verwaltung und Zivilgesellschaft? Anke Simone Schad entwickelt anhand der Beispiele Linz und Graz einen Rahmen für Governance-Analysen und bietet darüber hinaus Antworten auf die Fragen, woran Cultural Governance oft scheitert und wie gutes Regieren idealerweise aussehen könnte.
Wie ansteckend ist Hassrede?
Authors: Bens Jonas
Published: April 2019

Ausgangspunkt des Beitrages von Jonas Bens ist die Vorstellung, dass aus Worten Taten werden; dass Hassrede auch zu Gewalttaten führt. Die Straftatbestände im nationalen und internationalen Strafrecht wie Volksverhetzung oder Anstachelung zum Völkermord gehen von dieser Kausalität von Hassrede und Verbrechen aus. Aufbauend auf rechts-, rhetorik- und affekttheoretischen Überlegungen stellt dieser Text heraus, dass eine Kausalität von Hassrede und Gewalttaten, die empirisch schwer zu fassen ist, grundsätzlich normativ festgelegt wird. Die Konsequenz ist der grundlegend politische Charakter der Hassredestraftaten. Die anhaltende Diskussion um die Angemessenheit der Strafbarkeit affektiven Sprechens berücksichtigt nicht immer ausreichend, dass dieses Problem kulturell und historisch wandelbaren politisch-moralischen Einschätzungen unterliegt.
Raum und Würde - Ein interdisziplinärer Dialog
Authors: Haltaufderheide Joschka , Otte Ina , Weber Philipp
Published: April 2019

Raum und Würde sind - jeder für sich und auf seine Weise - konstitutive Begriffe der menschlichen Existenz. Dieser Beitrag untersucht ihre konzeptuellen Verknüpfungspunkte und entwirft das Programm eines normativ orientierten Raumdiskurses, der in dieser Form ein begriffliches Novum vorstellt. Ausgehend von der Analyse des Begriffs der Würde als konzeptuell unterbestimmtes Konstrukt, das stetiger lebensweltlicher Aktualisierung bedarf, wird »Raum« als Bedingung der Möglichkeiten des Handelns rekonstruiert. Den Gedanken des Spatial Turns folgend werden so Möglichkeiten einer kritischen normativen Befragung aufgezeigt: Die Räume die uns umgeben sind nicht zufällig, sie sind gemacht. Aber: Sind sie auch so, wie sie sein sollten?
Projektbeschreibung: Hospiz als (letzter) Lebensraum
Authors: Backhaus Nils , Haltaufderheide Joschka , Lamker Christian , Otte Ina , Reichert Stefanie
Published: April 2019

Die Würde aller Menschen zu achten bildet einen wesentlichen Eckpfeiler der Diskussion unseres Zusammenlebens in allen Räumen und allen Phasen des Lebens. Der Begriff der Würde und eines würdevollen Lebensendes rücken auch immer mehr in den Fokus von Sterbebegleitung, Hospizarbeit und Palliativmedizin. Unter der Maßgabe einer interdisziplinären Betrachtung entwickelt dieser Beitrag die konzeptuellen und inhaltlichen Grundlagen für die Erforschung von Würde im Lebensraum Hospiz. Er beschreibt weiterhin das methodische Vorgehen einer empirischen Rekonstruktion würdevoller (letzter) Lebensräume am Beispiel der Zusammenarbeit der Arbeitsgruppe »Spaces of Dignity« der Global Young Faculty mit dem Hospiz Am Ostpark in Dortmund.
Enfances à l’école
Authors: Giraud Frédérique
Published: April 2019

L’enjeu de ce dossier est de rappeler, contre la tentation « naturalisante » du monde social, que la définition scolaire de l’enfance, comme un âge des apprentissages, n’est ni naturelle, ni unanimement partagée par les acteurs en charge de son instruction. Les professionnels de l’éducation des enfants ne partageant ni la même définition de ce que sont des enfants ou des élèves, ni les mêmes représentations de ce qu’ils devraient être capables de faire ou d’apprendre, mettent en œuvre des pratiques hétérogènes. C’est pourquoi le mot enfances est proposé au pluriel : il s’agit bien de poser comme hypothèse de travail indépassable que « l’enfance n’est qu’un mot », à l’instar de Bourdieu qui démontrait que l’on ne pouvait parler de la jeunesse au singulier (1980). Le sociologue rappelle en effet que l’on ne peut raisonnablement regrouper sous un même vocable des jeunes qui n’ont rien de commun du point de vue de leurs origines sociales et de leurs ethos de classe.
Innowacyjność w edukacji językowej a profesjonalizm nauczyciela
Authors: Droździał-Szelest Krystyna
Published: April 2019

Innovation in language education, just as in any other discipline, is connected with changes whose primary goal is to make the process of language learning/language teaching more efficient. Examples of such innovations include, for instance, task based instruction, computer assisted language learning or the use of portfolio as a means of assessment.Innovation implies a new, qualitatively different perception of the language learning/ language teaching process, roles of teachers and learners, use of materials etc., hence it is believed to constitute a challenge for language teachers and their professionalism. The present article is an attempt to answer the question whether and to what extent the language teaching profession is actually prepared to deal with innovation.
Beata Gałan LA METHODE D’ENSEIGNEMENT A DISTANCE DANS LE DEVELOPPEMENT DE LA COMPETENCE REDACTIONNELLE EN LANGUE ETRANGERE
Authors: Karpińska-Szaj Katarzyna
Published: April 2019

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FACHSPRACHSPEZIFISCHER WORTSCHATZ ALS INSTRUMENT ZUR MARKENPFLEGE AM BEISPIEL DER KATEGORIE ELEKTROMOBILITÄT IM VOLKSWAGEN MAGAZIN
Authors: Błaszkowska Hanka
Published: April 2019

The article explores the influence of the specialised language on the shaping of the image of the German car brand Volkswagen. The analysed material comprises marketing texts from an image magazine of the Volkswagen Magazin brand, available on the company’s website. The issue will be examined on the basis of the semantic category of Electro Mobility, which constitutes a subcategory of the semantic category of innovation, which in turn is currently the company’s main area of activity and the focus of all actions, also linguistic, in terms of shaping the brand’s image. The specialised language in the texts from the Magazine, a digital journal, whose articles resemble forms of journalistic writing, limits itself mainly to specialist vocabulary – the technical vocabulary referring to automotive technology, as well as pseudo-specialised language, whose role is merely to evoke technical connotations. Both types of specialist terminology contribute to the restoring of the reputation of the brand in the eyes of the consumers, which has been severely affected as a result of the emissions scandal in 2015.
INVESTIGATING THE USE OF WEB 2.0 TOOLS FOR TOEFL IBT SPEAKING PRACTICE TEST
Authors: Bury Beata
Published: April 2019

The use of independent and integrated speaking tasks represents a distinctive element of the TOEFL iBT speaking exam. Integrated tasks that involve synthesizing and summarizing information presented in reading and listening materials have the potential to generate new test preparation strategies. Language teachers, whether in schools or colleges, have started using Web 2.0. tools in order to prepare students for language exams. It is asserted that Web 2.0. tools support active and meaningful learning and help students to express themselves on a particular subject. This paper describes the use of Web 2.0. tools to simulate TOEFL iBT-style speaking exercises and improve the students’ test taking ability in speaking during a course for kindergarten teachers in Andychów. Web-based activities were also implemented to help students overcome their fear of speaking. Also discussed are the main problems encountered, both pedagogical and technical, and what was done to solve them. Student feedback from an end-of-the-semester survey and from qualitative interviews is shared. The survey study shows that the use of Web 2.0. tools was a key feature of exam preparation on this intensive course. It is agreed that speaking skills of students can be improved through careful implementation of Web 2.0. tools.
MELIC TRANSLATION
Authors: Szota Weronika
Published: April 2019

In the following paper the author presents selected theories and approaches related to the translation of songs. She believes that these are crucial in understanding the melic translation process. Some aspects of the melic translation process itself, especially those connected with the translator’s decision, are also mentioned. They are described in order to show the need for an interdisciplinary perspective when approaching the topic. The main aim of the article is to present a possible solution for song translation with reference to the theories presented. The solution proposed involves the need to keep in mind not only ‘the message’ of the song, semantic dominant, harmonic dominant, and ‘the sound’ but also the fact that children are the main recipients.
LOGISTIK AN DER GERMANISTIK – WARUM NICHT? EIN PLÄDOYER FÜR DEN FACHSPRACHENUNTERRICHT AN DER UNIVERSITÄT
Authors: Strzelecka Grażyna
Published: April 2019

Not often do we encounter a specialized foreign language course at a university humanities department. However, why should foreign language students not be provided with practical knowledge which may be useful in future professional life? The article presents an experiment conducted with the participation of MA students of German studies at Warsaw University. The aim is to teach language skills, as well as convey professional knowledge in the CLIL formula, which is becoming more and more popular. It is consistent with requests of students themselves. Logistics is a useful introduction to various branches of the economy. Considering that the German language is becoming more and more important in business-related professions, the topics discussed in this course may be required in logistics, forwarding and other areas. In addition to traditional logistics topics, such as transport, storage and waste disposal, we also discuss topics such as business correspondence or negotiations and practice translations.
STUDENT-GENERATED COMMUNICATION ACTIVITIES IN AN ENGLISH FOR SPECIFIC PURPOSES COURSE
Authors: Wierciak Anna
Published: April 2019

Designing English for Specific Purposes (ESP) courses is a challenging task. The teacher often has to cope with time constraints, shortage of resources as well as his or her insufficient knowledge of a given field of study. Students enrolled in a course are often consulted about the source of materials for instruction. The process of developing ESP tasks can be made easier and less time-consuming by means of employing student-generated communication activities which draw on learner-based approaches to teaching. The paper contains a collection of student-generated tasks that can be successfully used at the preparatory, follow-up or main stage of an ESP class. In the author’s teaching context on numerous occasions they have triggered lively exchanges between students: discussion, brainstorming, or negotiation. Student-generated activities naturally develop collaboration and autonomy, which are essential in the workplace environment. Just like communication skills, they have to be taught explicitly due to the fact that in the area of soft skills there exist considerable differences at the personal and culture-specific level. Finally, since students’ specialist knowledge is usually much better than that of the teacher, student-generated activities tend to be to the point, up-to date, or more precise with respect to the course objectives.
Die 1990er Jahre als Epochenschwelle? Der Umbau der Deutschland AG zwischen Traditionsbruch und Kontinuitätswahrung
Authors: Berghoff Hartmut
Published: April 2019

Dieser Aufsatz befasst sich mit den Umbrüchen der 1990er Jahre in der Wirtschaft der Bundesrepublik und fragt nach dem Verhältnis von Diskontinuität und Kontinuität. Ausgehend von der Diskussion um die „Varieties of Capitalism“ wird diskutiert, inwieweit sich der koordinierte Kapitalismus deutscher Spielart auflöste. Im Einzelnen werden die Deregulierung des Kapitalmarktes, die Finanzialisierung der Unternehmen und ihre zunehmende Plastizität sowie die Veränderungen von Management und Arbeitsbeziehungen thematisiert. Auch wenn sich tiefgreifende Umbrüche, insbesondere die Aushöhlung traditioneller Sicherheiten nachweisen lassen, löste sich die Deutschland AG keineswegs auf. Vielmehr nahm sie lediglich partiell Elemente des angelsächsischen Modells auf. Insgesamt flexibilisierte und modernisierte sie sich.
What can we learn from other countries—lessons from the CAJC Happiness Report
Authors: Roeth Anjali A.
Published: April 2019

Most countries have their own programs and requirements for surgical residency. To investigate the differences as well as the advantages and disadvantages of the programs and to explore the happiness of the residents in the different countries, the Surgical Working Group of “Young Surgeons” of the German Society for General and Visceral Surgery has designed a questionnaire. It focuses on three parts: structural and legal requirements, operating room (OR)- and non-OR-related content of the program, and contentment of the residents. In this opinion paper, first the results are shared by the description of the programs in nine different countries. It is shown that the requirements to become a surgeon differ highly between the different countries. Nonetheless, a structured curriculum, the possibility of feedback or a surgical mentoring program, and transparency regarding the OR schedule seem to be important to all residents to reach job satisfaction.
The aqueous and methanol extracts of Bambusa vulgaris (Poaceae) improve calcium and phosphorus levels, and bone microstructure in ovariectomized model of osteoporosis
Authors: Watcho Pierre , Guiadem Kamto Kamto Bernadette , Defo Deeh Patrick Brice , Nguelefack Telesphore Benoit , Kamanyi Albert , Kamtchouing Pierre
Published: April 2019

Background

Osteoporosis represents the most common metabolic bone disease. Bambusa vulgaris (Poaceae) is a plant with potential antiosteoporotic effects, due to its phytoestrogenic, antioxidative, and anti-inflammatory properties. This study was undertaken to evaluate the effects of aqueous and methanol extracts of B. vulgaris on osteoporosis in rats.

Methods

Adult female Wistar rats were randomly divided into normal (n = 6) and ovariectomized (n = 42) groups. Twelve weeks after ovariectomy, animals were treated for 4 weeks as follows: distilled water (10 mL/kg, per os (p.o.)), 17β-estradiol (10 μg/kg, intraperitoneal (i.p.)), soya oil (1 mL/kg, i.p.), aqueous or methanol extract of B. vulgaris (55 or 110 mg/kg, p.o.). All rats were weighed daily and sacrificed on day 29. Plasma was collected, and the uterus and femur were dissected out, weighed, and used for biochemical and histological measurements.

Results

In the untreated ovariectomized females, a non-significant (p > 0.05) increase in body weight and a significant decrease (p < 0.001) in the uterine and bone weights were recorded. Ovariectomy also significantly (p < 0.001) lowered the bone calcium and phosphorus concentrations, and deteriorated the microarchitecture of the femur. Interestingly, B. vulgaris extracts significantly (p < 0.001) improved the bone calcium concentration and femur microarchitecture (increase in trabecular bone density, reorganization of the trabecular network, and increase in bone marrow) with estrogenic-like effects compared to 17β-estradiol.

Conclusion

These results suggest that B. vulgaris is a potential therapeutic drug for the treatment of osteoporosis. The present findings further justify the ethno-medicinal claims of B. vulgaris.
In vitromodulation of cytochrome P450 isozymes and pharmacokinetics of caffeine by extracts ofHibiscus sabdariffaLinn calyx
Authors: Showande Johnson Segun , Igbinoba Sharon Iyobor , Kajula Marena , Hokkanen Juho , Tolonen Ari , Adegbolagun Olayemi Modupe , Fakeye Titilayo Oyelola
Published: April 2019

Background

Hibiscus sabdariffabeverage (HSB) is widely consumed as a medicinal herb and sometimes used concomitantly with drugs. This study evaluated thein vitroinhibitory potential of the aqueous extract ofH. sabdariffacalyces (AEHS) on selected cytochrome P450 (CYP) isozymes and the effect of HSB on the pharmacokinetics of caffeinein vivo.

Methods

In vitroinhibitions of eight major CYP isozymes by AEHS were estimated by monitoring CYP-specific model reactions of 10 CYP probe substrates usingN-in-one assay method. Subsequently, an open, randomized, two-period crossover design was used to evaluate the effect of HSB on the pharmacokinetics of single-dose 200 mg caffeine in six healthy human volunteers. Blood samples were obtained at specific times over a 24 h period. Probe drugs and metabolites were analyzed in their respective matrices with ultra-performance liquid chromatography/mass spectrometer/mass spectrometer and reversed-phase high-performance liquid chromatography/ultraviolet detection.

Results

TheH. sabdariffaaqueous extract weakly inhibited the selected CYP isozymesin vitro, with IC50of >100 μgmL-1in the order of CYP1A2 > CYP2C8 > CYP2B6 >> CYP2D6 > CYP2C19 > CYP3A4 > CYP2A6 > CYP2C9. HSB decreased terminal t1/2and Tmaxof caffeine by 13.6% and 13.0%, respectively, and increased Cmaxby 10.3%. Point estimates of primary pharmacokinetic endpoints, Cmax= 1.142 (90% confidence interval (CI) = 0.882, 1.480) and AUC0–∞= 0.992 (90% CI = 0.745, 1.320), were outside the 90% CI of 0.8–1.25 bioequivalence limits.

Conclusion

The aqueous extract ofH. sabdariffaweakly inhibited eight CYP isozymesin vitro, but HSB modified the exposure to caffeine in human. Caution should be exercised in administering HSB with caffeine or similar substrates of CYP1A2 until more clinical data are available.
Basic Functions of Fiber Bragg Grating Effects on the Optical Fiber Systems Performance Efficiency
Authors: Amiri IS , Zaki Rashed Ahmed Nabih , Yupapin P
Published: April 2019

The study presents the basic apodization and chirp functions based fiber Bragg grating (FBG) for upgrading optical fiber performance efficiency. Variations of apodization and chirp functions are studied with grating length variations. Optical power after FBG, signal to noise ratio, maximum Q-factor, and output power are measured in the presence of the chirp functions. Gaussian apodization function has outlined good performance than other proposed apodization functions. As well as linear chirp function is better performance than other chirp functions. The optical system performance tested with/without chirp effects with high bit rates.
Transpacific Resonances and Affiliations in Leanne Dunic’sto Love the Coming Endand Ruth Ozeki’sthe Tale for the Time Being
Authors: O’Brien Michelle
Published: April 2019

This article examines methods of tracing affiliations across transpacific critiques through a reading of Leanne Dunic’sTo Love the Coming Endand Ruth Ozeki’sThe Tale for the Time Being. The article proposes that, rather than reproducing a nation-bound framing of the 2011 earthquake off the Pacific coast of Tōhoku that envisions it as a solely Japanese crisis, Dunic’s and Ozeki’s works explore what it would mean to read the earthquake and its aftermath as a transpacific event. It argues that these works facilitate new relations between national cultures and the global, suggesting that, by narrating the earthquake and recovering its transpacific resonances, both works recover and write transcultural links that are obscured in nation-bound narratives of events. By self-reflexively commenting on this process of creative forms of transpacific intimacy, Dunic’s and Ozeki’s works directly address the potential for literary narratives to implicate individuals from disparate nations in a global, historical, narrative of events
Mechanistic role of plant-based bitter principles and bitterness prediction for natural product studies I: Database and methods
Authors: Ntie-Kang Fidele
Published: April 2019

This chapter discusses the rationale behind the bitter sensation elicited by chemical compounds, focusing on natural products. Emphasis has been placed on a brief presentation of BitterDB (the database of bitter compounds), along with available methods for the prediction of bitterness in compounds. The fundamental basis for explaining bitterness has been provided, based on the structural features of human bitter taste receptors and have been used to shed light on the mechanistic role of a few out of the 25 known human taste receptors to provide the foundation for understanding how bitter compounds interact with their receptors. Some case studies of ligand-based prediction models based on 2D fingerprints and 3D pharmacophores, along with machine learning methods have been provided. The chapter closes with an attempt to establish the relationship between bitterness and toxicity.
Transparent Conducting Oxide Films for Various Applications: A Review
Authors: Afre Rakesh A. , Sharma Nallin , Sharon Maheshwar , Sharon Madhuri
Published: April 2019

This review encompasses properties and applications of polycrystalline or amorphous, Transparent Conducting Oxides (TCO) semiconductors. Coexistence of electrical conductivity and optical transparency in TCO depends on the nature, number and atomic arrangements of metal cations in oxides, on the resident morphology and presence of intrinsic or introduced defects. Therefore, TCO semiconductors that are impurity-doped as well as the ternary compounds and multi-component oxides consisting of combinations are discussed. Expanding use of TCO is endangered by scarcity, cost of In, fragility of glass, limited transparency to visible light, instability above >200 °C, non-flexible for application of flexible solar cell; thus driving search for alternatives such as graphene or CNT, that are more stable under acidic, alkaline, oxidizing, reducing and elevated temperature. There are reasons to conclude that there is need to develop large area deposition techniques to produce TCO films with high deposition rate. TCOs are mostly n-type semiconductors, but p-type are also being researched
Immobilization of Lipase on Iron Oxide Organic/Inorganic Hybrid Particles: A Review Article
Authors: Ali Zafar , Li Tian , Khan Muhammad , Ali Nisar , Zhang Qiuyu
Published: April 2019

In last few decades the demand of lipase has been dramatically increase due to its useful use in numbers of biochemical industries. Varieties of natural and synthetic carriers and methodologies have been used to improve lipase activities by the process of immobilization in order to enhance its activities in term of its resistance to high temperature, pH and to increase its reusibity and storage capacity. Due to the expensive nature the recycling of the lipase has been the target of the researchers to decrease its cost in the industrial process. Magnetic iron oxide organic/inorganic hybrid nanoparticles as a support have been mostly used in the lipase immobilization due its large surface area, less toxicity, bio compatibility, easily functionalization, separation avoiding long time consuming process like filtration and centrifuging.
A Brief Review of Structural, Electrical and Electrochemical Properties of Zinc Oxide Nanoparticles
Authors: Parihar Vandana , Raja Mohan , Paulose Rini
Published: April 2019

Nanotechnology allocate with the production and usage of material with nanoscale dimension, nanoparticles are large surface area to volume ratio and thus very specific properties. Zinc oxide (ZnO) nanoparticles had been in current studies due to its large bandwidth and high exciton binding energy and it has prospective applications such as electronic, optical, mechanical, magnetic and chemical properties that are significantly different from those of bulk counterpart. The aims of this review to provide a comprehensive view on structural, synthesis and electrochemical properties of the ZnO nanoparticles, which were synthesized by different methods.
Negative Magnetization in Perovskite RTO3 (R=Rare-Earth, T=Cr/Mn)
Authors: Biswas Sanjay , Pal Sudipta
Published: April 2019

The present review presents a detail discussion of the phenomenon of magnetization reversal (or negativemagnetization) phenomena.Avariety of magnetically ordered systems shows negative magnetization. However, this negative magnetization in these materials does not arise due to diamagnetism. Here we have focused a special group of ceramic oxides namely RTO3 (R=rare-earth, T=Cr/Mn). In these oxides sign of the magnetic moment reverses mainly due to negative exchange coupling among ferromagnetic/canted-antiferromagnetic and paramagnetic sublattices. Finally, the practical utilization of this type of materials is included in this review.
Poly(Hydroxybutyrate) and Norbixin as Biomaterials In Biological Applications
Authors: Sousa R. C. , Almeida F. R. C. , Viana V. G. F. , Carvalho L. F. M. , Vasconcelos D. F. P.
Published: April 2019

This review presents the survey of performance of biomaterials prepared using norbixina and poly(hydroxybutyrate) as biomaterials in biological applications. Biomaterials can replace and/or stimulate biological systems that no longer have their functions, such as the restoration of tissue functions. In the field of biomaterials, norbixin is an antioxidant dicarboxylic carotenoid found in Bixa orellana L. and poly(hydroxybutyrate) (PHB) is a natural polymer that has characteristics of biodegradability and biocompatibility. There is a shortage of studies involving such constituents together as biomembranes in tissue healing with repair of cutaneous wounds or bone regeneration, although both present promising research that suggests its effectiveness as a guide for tissue regeneration.
Microstructure and Properties of Fine Grained Cu-Cr-Zr Alloys after Termo-Mechanical Treatments
Authors: Morozova A. , Mishnev R. , Belyakov A. , Kaibyshev R.
Published: April 2019

Cu-Cr-Zr alloys provide an excellent combination of strength and electric conductivity and are frequently used as engineering materials in various electric/electronic devises. The present review deals with the microstructural design of Cu-Cr-Zr alloys, their alloying concept, thermo-mechanical processing based on technique of severe plastic deformation, physical mechanisms responsible for high strength and electric conductivity. The influences of microstructure and a dispersion of secondary phases on the mechanical properties and electric conductivity are discussed in detail. First, precipitation sequences during aging that leads to depletion of Zr and Cr solutes from Cu solution are critically reviewed in close connection with interaction mechanisms between dislocations and particles. Then, the main structure-property relationships of Cu-Cr-Zr alloys are considered. Finally, the strengthening of Cu-Cr-Zr alloys through severe plastic deformation by means of submicrocrystalline/nanocrystalline structure and increasing dislocation density as well as the effects of post-deformation heat treatment on the mechanical and electric properties are discussed.
Magnetic Sio2-Fe3O4 Nanocomposites as Carriers of Ibuprofen for Controlled Release Applications
Authors: González-Hurtado M. , Marins J. A. , Soares B. Guenther , Briones J. Rieumont , Rodríguez A. Rodríguez , Ortiz-Islas E.
Published: April 2019

In the present paper, we report the preparation and characterization of magnetic silica nanostructured materials that were used as ibuprofen drug molecule carriers. This work was aimed at obtaining drug release systems sensitive to a magnetic field to be directed to target sites. The preparation of the silica nanostructuredmaterials started with the synthesis of magnetite (Fe3O4) nanoparticles that were added subsequently during the hydrolysis and condensation of tetraethyl-orthosilicate (TEOS) to obtain SiO2-Fe3O4 nanocomposites. The ibuprofen molecules were added simultaneously with magnetite nanoparticles. The in vitro ibuprofen release profiles were analyzed, showing a typical controlled release for all materials studied. The nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning microscopy (SEM), thermogravimetric analysis (TGA), N2 adsorption-desorption isotherms; magnetic studies were also performed. The obtained materials showed low superparamagnetic values, and saturation behavior was also observed. It was demonstrated that ibuprofen does not affect the magnetic behavior of magnetite, indicating its possible use in medical applications.
Design and Construction of an Embedded Fuzzy-Optical System to Characterize Metamaterials
Authors: Castañeda-Miranda Alejandro , Castaño Víctor M.
Published: April 2019

A fuzzy logic-based embedded system to characterize materials and metamaterials is presented. Trapezoidal and Gaussian profiles, used as membership functions, allow to classify materials despite variations on light intensity. The results on various materials show the capacity of the system to calculate the refractive index as a complex number, through a fourth order equation. Since all the roots of the equarion, including imaginary ones, the system allow to characterize metamaterials. The embedded character of the systems allows to use it as an external module for most commercial equipments.
Tuning the Structure and the Mechanical Properties of Ultrafine Grain Al–Zn Alloys by Short Time Annealing
Authors: Bobruk E.V. , Sauvage X. , Zakirov A.M. , Enikeev N.A.
Published: April 2019

Solid solution treated Al-Zn alloys with different Zn contents (10 and 30 wt.%) have been nanostructured by severe plastic deformation (SPD) via equal-channel angular pressing method. In-situ transmission electron microscopy observations have been used to follow microstructure evolutions upon annealing. It was shown that SPD leads to the precipitation of Zn particles and that this partial solid solution decomposition was more pronounced in the Al- 30%Zn alloy. Annealing at temperatures in range of 200 to 250 °C led to visible dissolution of Zn particles in both alloys and to formation of extensive grain boundary segregations of Zn. This approach helped to design short term annealing treatments leading to specific ultrafine grain structures that could be achieved by static annealing on bulk samples. Last, the tensile behavior of these materials has been investigated with a special emphasis on the influence of the strain rate on the yield stress and on the elongation to failure. It is shown that in any case the yield stress is mainly controlled by the grain size, while a low volume fraction of Zn phase leads to a relatively modest ductility.
Influence of Severe Plastic Deformation on Microstructure, Strength and Electrical Conductivity of Aged Al–0.4Zr(Wt.%) Alloy
Authors: Orlova T.S. , Mavlyutov A.M. , Latynina T.A. , Ubyivovk E.V. , Murashkin M.Yu. , Schneider R. , Gerthsen D. , Valiev R.Z.
Published: April 2019

Microstructure evolution of an Al-0.4Zr(wt.%) alloy after isothermal aging (AG) and subsequent high pressure torsion (HPT) and its impact on strength and electrical conductivity has been investigated. Microstructure was characterized by X-ray diffraction, electron backscatter diffraction, transmission electron microscopy (TEM) and electron energy-dispersive X-ray spectroscopy in TEM. The initial Al-0.4Zr(wt.%) alloy obtained by combined casting and rolling presents solid solution of Zr in Al matrix. Aging at 375 °C for 60 h leads to formation of uniformly distributed metastable Al3Zr precipitates with the average diameter of 13 nm, resulting thereby in a decrease of strength sUTS from 128 to 95 MPa and in increase of conductivity from 50.7 to 58.8% IACS at ambient temperature. The subsequent HPT processing leads to grain refinement and partial dissolution of the Al3Zr precipitates that is accompanied by enrichment of solid solution by Zr atoms and by coarsening of the remaining Al3Zr precipitates. The combination of AG and HPT provides the strength and the conductivity at ambient temperature which do not decrease under annealing up to 230 °C. Moreover, additional strengthening accompanied by an increase in conductivity was found for AG-HPT samples after annealing at Tan=230 °C for 1 h, that provides the best combination of the strength of sUTS=142 MPa and the conductivity of 58.3% IACS. Contribution of different possible mechanisms into strength and charge scattering are analyzed on the basis of specific microstructural features. The analysis indicates a suppression of strengthening by the Orowan mechanism in AG and AG-HPT samples. In all the studied states, i.e. initial, after AG, and subsequent HPT, grain boundary strengthening is found to be the main strengthening mechanism.
Adhesion and Mechanical Properties of PDMS-Based Materials Probed with AFM: A Review
Authors: Vlassov S. , Oras S. , Antsov M. , Sosnin I. , Polyakov B. , Shutka A. , Krauchanka M. Yu. , Dorogin L. M.
Published: April 2019

Polydimethylsiloxane (PDMS) is the most widely used silicon-based organic polymer, and is particularly known for its unusual rheological properties. PDMS has found extensive usage in various fields ranging from microfluidics and flexible electronics to cosmetics and food industry. In certain applications, like e.g. dry adhesives or dry transfer of 2D materials, adhesive properties of PDMS play crucial role. In this review we focus on probing the mechanical and adhesive properties of PDMS by means of atomic force microscopy (AFM). Main advantages and limitations of AFM-based measurements in comparison to macroscopic tests are discussed.
Magnetometric Study Of ZnO/CoO Nanocomposites
Authors: Typek J. , Guskos N. , Zolnierkiewicz G. , Sibera D. , Narkiewicz U.
Published: April 2019

ZnO nanoparticles doped with transition metal ions are intensively studied nanomaterials, due to their charges and the spins of electrons that provides new magnetic, optical and transport properties. They find a vast range of applications, ranging from optoelectronics to spintronics. In this context especially important is the room temperature ferromagnetism observed for ZnO doped nanomaterials, although this phenomenon is still a controversial and open topic in material science, mostly due to low reproducibility of results from samples prepared by different techniques. In the first part of this article a short review of papers using magnetometric methods to determine the magnetic characteristics of Co-doped ZnO nanomaterials is presented. Different models introduced to explain room temperature ferromagnetism (carrier mediated ferromagnetism, Co2+-oxygen vacancy pairs, blocked superparamagnetic clusters, Co2+-Zn interstitial pairs, heterogeneous distribution of magnetic ions) are examined and discussed. In the second part, magnetisation study of a new series of nCoO/(1-n)ZnO nanocomposites synthesized by hydrothermal method under higher than previously applied pressure will be described. The obtained experimental results will be analysed and information on magnetic systems responsible for the observed characteristics and the involved magnetic interactions will be deduced.
The Effect of Crystallographic Orientation on the Deformation Mechanisms of Nial Nanofilms under Tension
Authors: Krylova Karina A. , Babicheva Rita I. , Zhou Kun , Bubenchikov Alexey M. , Ekomasov Evgenii G. , Dmitriev Sergey V.
Published: April 2019

Molecular dynamics is applied to study the effect of crystallographic orientation on the plastic deformation mechanisms and mechanical properties of NiAl intermetallic nanofilms subjected to uniaxial tension. It is observed that the deformation mechanisms qualitatively depend on the crystallographic orientation of the nanofilms with respect to the loading direction. Plastic deformation of the nanofilms along [557] crystallographic direction is associated with the edge dislocation sliding in the slip system [001](110). As for the nanofilms stretched along [554] and [111] directions, their deformation occurs first through the dislocation sliding followed by the formation of (112)[11 1] twins. Uniaxial tension of the nanofilms along [559] and [55 11] leads to the nucleation and growth of a martensitic phase followed by their rupture along an interface. The maximum (minimum) strength of 9.9 (7.0) GPa is observed for the nanofilms stretched along the [559] ([554]) crystallographic direction, while the largest (smallest) strain to failure of 27 (15)% is for [559] ([55 11]). Various deformation mechanisms of the nanofilms are explained through computing the Schmid factor for the operational slip system. The results indicate that the crystallographic orientation is among the key parameters controlling the deformation mechanisms and mechanical properties of intermetallic nanofilms.
Effect of Crack Bridging on the Toughening of Ceramic/Graphene Composites
Authors: Bobylev S.V. , Sheinerman A.G.
Published: April 2019

A model is proposed describing the effect of crack bridging on the fracture toughness of ceramic/graphene composites. The dependences of the fracture toughness on the graphene content and the sizes of the graphene platelets are calculated in the exemplary case of yttria stabilized zirconia (YSZ)/graphene composites. The calculations predict that if crack bridging prevails over crack deflection during crack growth, the maximum toughening can be achieved in the case of long graphene platelets provided that the latter do not rupture and adhere well to the matrix. The model shows good correlation with the experimental data at low graphene concentrations.