Bee Products as Functional Food

The studies that reveal the impact of the bee products on overall health are accompanied by new researches every year, and the importance of these researches are gradually on the rise. Bee products that are used as food and food supplements and drug concentrations in the historic process are drawing the attention with their marvellous characteristic features. The search for nourishment of the body on behalf of healthy living is currently being searched by many people. Therefore, the consumption of products that protect the health appears as the primary preference of people. In the light of this recent tendency, food sector is now offering well-supported products that are suitable for this preference. At this point, bee products such as honey, pollen, bee bread, royal jelly and propolis gain importance as functional food with their nutritious features that help in protecting the health. In this article, within the consideration of the researches that evaluate bee products as functional food, we aim to introduce the prominence of bee products in our nourishment and overall health

CDS Implied Default Probabilities: A Study of a Reduced Form Model for Credit Risk

ABSTRACT This study estimates risk-neutral probability of default from quoted Credit Default Swap (CDS) spreads by employing Hull and White (2000 and 2003) reduced form model for pricing CDS. Once fixing the recovery rate at a predetermined level, we introduce default probability density, q(t) in two forms; a continuous piecewise linear function and a step function. Considering CDS maturity times we extract default probability densities recursively from the model based on the CDS spreads quoted for each maturity. To apply the method to real life data, we construct term structure of default probability densities of 10 UK firms operating in various sectors and with different credit ratings over the three measurement dates: May 1, 2007, December 31, 2008 and December 31, 2009. These dates are believed to reflect changes in market conditions during the period 2007-2009 which covers subprime mortgage crisis. For this analysis, we use one year forward rates estimated from treasury rates as reference risk-free rate. The results suggest that the default probability densities record lowest values in 2007 for most of the firms and the typical positive relation between the default probability and maturity reverses in 2008 when default probability densities usually decline with longer maturities. We also test the model’s performance in terms of discriminating defaulters from non-defaulters by means of Receiver Operating Characteristics (ROC). We use U.S. firms for this analysis and compare performances of different default probability measures calculated based on the CDS implied default probabilities. We find that our model has a very strong discriminatory power in terms of firm defaults, despite a weakness arisen from period dependent analysis due to insufficient CDS data

Minimally-invasive Microneedle-based Biosensor Array for Simultaneous Lactate and Glucose Monitoring in Artificial Interstitial Fluid

Here we report the first mediated pain free microneedle‐based biosensor array for the continuous and simultaneous monitoring of lactate and glucose in artificial interstitial fluid (ISF). The gold surface of the microneedles has been modified by electrodeposition of Au‐multiwalled carbon nanotubes (MWCNTs) and successively by electropolymerization of the redox mediator, methylene blue (MB). Functionalization of the Au‐MWCNTs/polyMB platform with the lactate oxidase (LOX) enzyme (working electrode 1) and with the FAD‐Glucose dehydrogenase (FADGDH) enzyme (working electrode 2) enabled the continuous monitoring of lactate and glucose in the artificial ISF. The lactate biosensor exhibited a high sensitivity (797.4±38.1 μA cm−2 mM−1), a good linear range (10–100 μM) with a detection limit of 3 μM. The performance of the glucose biosensor were also good with a sensitivity of 405.2±24.1 μA cm−2 mM−1, a linear range between 0.05 and 5 mM and a detection limit of 7 μM. The biosensor array was tested to detect the amount of lactate generated after 100 minutes of cycling exercise (12 mM) and of glucose after a normal meal for a healthy patient (10 mM). The results reveal that the new microneedles‐based biosensor array seems to be a promising tool for the development of real‐time wearable devices with a variety of sport medicine and clinical care applications

CDS Implied Default Probabilities: A Study of a Reduced Form Model for Credit Risk

ABSTRACT This study estimates risk-neutral probability of default from quoted Credit Default Swap (CDS) spreads by employing Hull and White (2000 and 2003) reduced form model for pricing CDS. Once fixing the recovery rate at a predetermined level, we introduce default probability density, q(t) in two forms; a continuous piecewise linear function and a step function. Considering CDS maturity times we extract default probability densities recursively from the model based on the CDS spreads quoted for each maturity. To apply the method to real life data, we construct term structure of default probability densities of 10 UK firms operating in various sectors and with different credit ratings over the three measurement dates: May 1, 2007, December 31, 2008 and December 31, 2009. These dates are believed to reflect changes in market conditions during the period 2007-2009 which covers subprime mortgage crisis. For this analysis, we use one year forward rates estimated from treasury rates as reference risk-free rate. The results suggest that the default probability densities record lowest values in 2007 for most of the firms and the typical positive relation between the default probability and maturity reverses in 2008 when default probability densities usually decline with longer maturities. We also test the model’s performance in terms of discriminating defaulters from non-defaulters by means of Receiver Operating Characteristics (ROC). We use U.S. firms for this analysis and compare performances of different default probability measures calculated based on the CDS implied default probabilities. We find that our model has a very strong discriminatory power in terms of firm defaults, despite a weakness arisen from period dependent analysis due to insufficient CDS data

Fumonisin B-1 and B-2 occurrence in dried fig fruits (Ficus carica L.) under Meander Valley's climatic conditions and relationship with fruit quality

WOS: 000297106700011PubMed ID: 21793684Fusarium is the agent causing endosepsis (internal rot) in fig fruits and it is widespread in fig orchards in the Aegean region. This research was conducted to determine the natural occurrence of fumonisin B-1 (FB1) and B-2 (FB2) on dried fig fruits of Sarilop (syn. Calimyrna) variety which are mainly grown in the Big and Small Meander Basins in the Aegean region, representing 60% of world dried fig production. A total of 262 samples belonging to two quality classes, Class A and Class cull, were collected from 12 different locations during the two crop years in 2004 and 2005. The fumonisin detection method is based on extraction with methanol-acetonitrile-water, derivatization with o-phthaldehyde and quantification by reversed-phase high-performance liquid chromatography with fluorescence detection. The mean concentrations of FB1 and FB2 in fumonisin-positive samples were 0.080 +/- 0.047 mu g g(-1) and 0.055 +/- 0.031 mu g g(-1) and ranged from LOD to 0.332 mu g g(-1) and from LOD to 0.198 mu g g(-1), respectively. The incidence of fumonisins significantly differed between the two crop years. This difference can be attributed to the alteration in the rainfall regime from mid-May to mid-August (7.2 mm in 2004, 90.9 mm in 2005) and number of humid wind currents from a westerly direction (183 in 2004, 492 in 2005) from the end of July and mid-August that may have triggered a higher incidence of Fusarium spp. and thus fumonisin production.TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [105 O 302]This project was partially supported by TUBITAK (105 O 302). The authors wish to thank the Erbeyli Fig Research Institute and Food Control Laboratory of Commodity Exchange of Aydin Province