Information and volatility

This study examines the volatility of daily stock returns and the volatility of returns during trading and non-trading hours for securities trading on the Istanbul Stock Exchange. Some unique characteristics of this exchange enable us to examine the reasons for the high volatility during trading hours. First, the price-determination procedure at the opening is the same as the pricing mechanism used during the rest of the day. Second, there is no specialist or market maker who sets prices. Third, there is a two-hour day break in trading during a business day. The volatility of daily return calculated from opening prices is found to be significantly higher than those calculated from closing prices in this market setting as well. Volatility of returns during trading periods is found to be higher than those during non-trading periods. Furthermore, per-hour volatility during the day break is higher than per-hour volatility during the night break. Findings of this study have some implications for the role of market maker and the impact of timing and length of a break in trading on the volatility of security returns. © 2002 M.E. Sharpe, Inc. All rights reserved

Diagnostic value of combined serum biomarkers for the evaluation of liver fibrosis in chronic hepatitis C infection: A multicenter, noninterventional, observational study

Background/Aims: The hepatitis C virus (HCV) infection is important cause of chronic hepatitis. Liver biopsy is considered the gold standard for assessment of fibrosis but this procedure is an invasive procedure. We aimed to evaluate the diagnostic efficiency of non-invasive serum biomarkers, separately and in combinations, on liver fibrosis in treatment-naive chronic hepatitis C (CHC) patients. Materials and Methods: Two hundred and sixteen treatment-naive CHC patients were enrolled from 32 locations across Turkey in this open-labelled, non-interventional prospective observational study. FibroTest®, aspartate aminotransferase-to-platelet ratio index(APRI), aspartate aminotransferase and alanine aminotransferase ratio (AAR), fibrosis index based on four factors (FIB-4), Age-platelet(AP) index and Forns index were measured and compared with Metavir scores got from liver biopsies. Results: Data from 182 patients with baseline liver biopsy were suitable for analysis. One hundred and twenty patients (65.9%) had F0-F1 fibrosis and 62 patients (34.1%) had F2-F4 fibrosis. APRI 0.732 area under the curve(AUC) indicated advanced fibrosis with 69% sensitivity and 77% specificity. FIB-4 0.732 AUC and FibroTest 0.715 AUC indicated advanced fibrosis with 69% and 78.4% sensitivity, and 75% and 71.4% specificity, respectively. The combined use of tests also led to an increase in AUC and specificity. Combinations of FibroTest with APRI and/or FIB-4, and FIB-4 with APRI were optimal for the evaluation of liver fibrosis. Conclusion: Fibrotest, FIB-4, APRI, AP index and Forns index exhibit good diagnostic performance for determining liver fibrosis in CHC patients, and the use of at least two tests together will increase their diagnostic value still further. © Copyright 2018 by The Turkish Society of Gastroenterology

Formation of different magnetic phases and high Curie temperature ferromagnetism in Fe57-implanted ZnO film

© 2014 Elsevier B.V. All rights reserved. We investigated magnetic properties of ZnO thin film implanted with Fe57 ions to the fluence of 1.00×1017 ions/cm2. Both vibrating sample magnetometry and magneto-optical Kerr effect measurements revealed strong room temperature ferromagnetism with similar hysteresis loops. Temperature dependent measurements showed a very high Curie temperature around 850 K. Conversion electron Mössbauer spectroscopy experiments proved the existence of paramagnetic Fe+3 and Fe+2 ions and also the presence of substitutional Fe atoms in the hexagonal ZnO crystal resulting in intrinsic ferromagnetic order

Study of ultrastructural changes on the cochleae caused by various intonations used in classical music

The aim of this study is to investigate the differences on ultrastructure of the cochleae caused by different classic musical opuses with different intonations. Guinea pigs were grouped into 3, one of which was the control and the other two were the experimental groups. While the first group, which was the control, was not exposed to any music, the second group was exposed to classic musical opuses with extensive intervals (40 decibel) and third group was exposed to classical music opuses with strained intonations (60 decibel) for 6 h a day with 15 min-intervals for totally 10 days. Cochleae tissue samples were taken from the guinea pigs at the end of the tenth day. They were examined at the electron microscopic level. In addition to compansatris processes on the cochleae, thickening on the stereocilias of hair cells and basal membranes and proliferation on the synaptic terminalles of afferent nerves caused by extensive intonations were observed. Extremely obvious degenerative differences such as damage in neuroepitelial cells, nerves and synaptic terminalles as well as compansatris processes caused by strained intonations were determined. As a result of all these observations it was concluded that continuously listening to the strained intonations used in musical opuses has a very harmful effect on the auditory system. © 2008 Academic Journals Inc

Biodiversity mainstreaming for healthy & sustainable food systems: A toolkit to support incorporating biodiversity into policies and programmes

The Biodiversity for Food and Nutrition Initiative (BFN Project) uses indigenous food biodiversity as a lens to address malnutrition, farmer livelihood resilience, and sustainability. Since 2012, the initiative has pioneered a cross-sectoral, partner-based approach to document and share information on 195 nutrient-rich, locally-adapted species ranging from African leafy vegetables to Amazonian fruits. Spearheaded by governments and research organizations in Brazil, Kenya, Sri Lanka, and Turkey, BFN developed a three-pronged methodology to ensure the conservation, revival, and promotion of these underutilised species. This toolkit is an open-access guide to mainstreaming biodiversity that draws on case studies across the four partner countries, outlining steps to 1) Provide Evidence; 2) Influence Policy, and 3) Raise Awareness. With an emphasis on both key focus areas and site-specific examples, the toolkit offers readers inspiration to adapt the work of BFN to other regions. Links to key resources collect additional information and contextualise the project methods, for example, in relation to the FAO Voluntary Guidelines for Mainstreaming Biodiversity into Policies, Programmes and National and Regional Plans on Nutrition. Focus points within the toolkit include how to make use of: National Biodiversity Strategy and Action Plans, school feeding and procurement, green employment, cultural festivals, and business cases for mainstreaming biodiversity

Fabrication of exchange coupled hard/soft magnetic nanocomposites: Correlation between composition, magnetic, optical and microwave properties

This paper studied the exchange coupling performance beside structural and microwave properties of SrFe12O19 (SFO) and x(CoTm0.01Tb0.01Fe1.98O4) (CoTmTb) (x ≤ 3.0) hard/soft ferrites nanocomposites (NCs). The structure and morphology of NCs were investigated by XRD, SEM, TEM and HR-TEM. Diffuse reflectance spectroscopic (DRS) measurements were applied on hexagonal ferrite, on spinel ferrite nanoparticles and on hard/soft NCs to specify the optical properties. Estimated Eg data are in a range between 1.32 and 1.79 eV. The magnetic properties were also inspected via measurements of magnetization (M) against magnetic field (H) at 300 K (RT) and 10 K (LT). The measurements performed at RT along with the plots of dM/dH versus H indicated that the NCs display good magnetic properties (exchange coupling behavior). The magnetic parameters such as (Ms, Mr, and Hc) show an enhancement in their values with an increasing the soft content at RT. Similarly, the maximum energy product (BH)max rises and reaches its max value for SFO/3(CoTmTb) NCs. Microwave properties of the SFO/x(CoTmTb) NCs were measured in the frequency range 33–50 GHz. From measured S11 and S21 parameters the main electrodynamic characteristics – permittivity and permeability (real and imaginary parts) were computed. © 2021 The Author(s)This work was financially supported by the Deanship for Scientific Research (Project application No. 2020-164-IRMC) of Imam Abdulrahman Bin Faisal University (IAU ? Saudi Arabia). Microwave characterization was partially supported by the Russian Science Foundation (Agreement No. 19-72-10071 from 06 Aug. 2019)

The bc 1 complexes of Rhodobacter sphaeroides and Rhodobacter capsulatus

Photosynthetic bacteria offer excellent experimental opportunities to explore both the structure and function of the ubiquinol-cytochrome c oxidoreductase ( bc 1 complex). In both Rhodobacter sphaeroides and Rhodobacter capsulatus , the bc 1 complex functions in both the aerobic respiratory chain and as an essential component of the photosynthetic electron transport chain. Because the bc 1 complex in these organisms can be functionally coupled to the photosynthetic reaction center, flash photolysis can be used to study electron flow through the enzyme and to examine the effects of various amino acid substitutions. During the past several years, numerous mutations have been generated in the cytochrome b subunit, in the Rieske iron-sulfur subunit, and in the cytochrome c 1 subunit. Both site-directed and random mutagenesis procedures have been utilized. Studies of these mutations have identified amino acid residues that are metal ligands, as well as those residues that are at or near either the quinol oxidase (Q o ) site or the quinol reductase (Q i ) site. The postulate that these two Q-sites are located on opposite sides of the membrane is supported by these studies. Current research is directed at exploring the details of the catalytic mechanism, the nature of the subunit interactions, and the assembly of this enzyme.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44795/1/10863_2004_Article_BF00762582.pd