bluuebunny/crossref_metadata_2025 huggingface dataset:
A Label-Free Microfluidic Biosensor for Activity Detection of Single Microalgae Cells Based on Chlorophyll Fluorescence
Authors: Wang Junsheng , Sun Jinyang , Song Yongxin , Xu Yongyi , Pan Xinxiang , Sun Yeqing , Li Dongqing
Published: November 2013

Detection of living microalgae cells is very important for ballast water treatment and analysis. Chlorophyll fluorescence is an indicator of photosynthetic activity and hence the living status of plant cells. In this paper, we developed a novel microfluidic biosensor system that can quickly and accurately detect the viability of single microalgae cells based on chlorophyll fluorescence. The system is composed of a laser diode as an excitation light source, a photodiode detector, a signal analysis circuit, and a microfluidic chip as a microalgae cell transportation platform. To demonstrate the utility of this system, six different living and dead algae samples (Karenia mikimotoi Hansen, Chlorella vulgaris, Nitzschia closterium, Platymonas subcordiformis, Pyramidomonas delicatula and Dunaliella salina) were tested. The developed biosensor can distinguish clearly between the living microalgae cells and the dead microalgae cells. The smallest microalgae cells that can be detected by using this biosensor are 3 μm ones. Even smaller microalgae cells could be detected by increasing the excitation light power. The developed microfluidic biosensor has great potential for in situ ballast water analysis.
A Manual Transportable Instrument Platform for Ground-Based Spectro-Directional Observations (ManTIS) and the Resultant Hyperspectral Field Goniometer System
Authors: Buchhorn Marcel , Petereit Reinhold , Heim Birgit
Published: November 2013

This article presents and technically describes a new field spectro-goniometer system for the ground-based characterization of the surface reflectance anisotropy under natural illumination conditions developed at the Alfred Wegener Institute (AWI). The spectro-goniometer consists of a Manual Transportable Instrument platform for ground-based Spectro-directional observations (ManTIS), and a hyperspectral sensor system. The presented measurement strategy shows that the AWI ManTIS field spectro-goniometer can deliver high quality hemispherical conical reflectance factor (HCRF) measurements with a pointing accuracy of ±6 cm within the constant observation center. The sampling of a ManTIS hemisphere (up to 30° viewing zenith, 360° viewing azimuth) needs approx. 18 min. The developed data processing chain in combination with the software used for the semi-automatic control provides a reliable method to reduce temporal effects during the measurements. The presented visualization and analysis approaches of the HCRF data of an Arctic low growing vegetation showcase prove the high quality of spectro-goniometer measurements. The patented low-cost and lightweight ManTIS instrument platform can be customized for various research needs and is available for purchase.
Impedimetric Aptasensor for Ochratoxin A Determination Based on Au Nanoparticles Stabilized with Hyper-Branched Polymer
Authors: Evtugyn Gennady , Porfireva Anna , Stepanova Veronika , Kutyreva Marianna , Gataulina Alfiya , Ulakhovich Nikolay , Evtugyn Vladimir , Hianik Tibor
Published: November 2013

An impedimetric aptasensor for ochratoxin A (OTA) detection has been developed on the base of a gold electrode covered with a new modifier consisting of electropolymerized Neutral Red and a mixture of Au nanoparticles suspended in the dendrimeric polymer Botlorn H30®. Thiolated aptamer specific to OTA was covalently attached to Au nanoparticles via Au-S bonding. The interaction of the aptamer with OTA induced the conformational switch of the aptamer from linear to guanine quadruplex form followed by consolidation of the surface layer and an increase of the charge transfer resistance. The aptasensor makes it possible to detect from 0.1 to 100 nM of OTA (limit of detection: 0.02 nM) in the presence of at least 50 fold excess of ochratoxin B. The applicability of the aptasensor for real sample assay was confirmed by testing spiked beer samples. The recovery of 2 nM OTA was found to be 70% for light beer and 78% for dark beer.
Multi-Wave and Hybrid Imaging Techniques: A New Direction for Nondestructive Testing and Structural Health Monitoring
Authors: Cheng Yuhua , Deng Yiming , Cao Jing , Xiong Xin , Bai Libing , Li Zhaojun
Published: November 2013

In this article, the state-of-the-art multi-wave and hybrid imaging techniques in the field of nondestructive evaluation and structural health monitoring were comprehensively reviewed. A new direction for assessment and health monitoring of various structures by capitalizing the advantages of those imaging methods was discussed. Although sharing similar system configurations, the imaging physics and principles of multi-wave phenomena and hybrid imaging methods are inherently different. After a brief introduction of nondestructive evaluation (NDE) , structure health monitoring (SHM) and their related challenges, several recent advances that have significantly extended imaging methods from laboratory development into practical applications were summarized, followed by conclusions and discussion on future directions.
An Observability Metric for Underwater Vehicle Localization Using Range Measurements
Authors: Arrichiello Filippo , Antonelli Gianluca , Aguiar Antonio , Pascoal Antonio
Published: November 2013

The paper addresses observability issues related to the general problem of single and multiple Autonomous Underwater Vehicle (AUV) localization using only range measurements. While an AUV is submerged, localization devices, such as Global Navigation Satellite Systems, are ineffective, due to the attenuation of electromagnetic waves. AUV localization based on dead reckoning techniques and the use of affordable motion sensor units is also not practical, due to divergence caused by sensor bias and drift. For these reasons, localization systems often build on trilateration algorithms that rely on the measurements of the ranges between an AUV and a set of fixed transponders using acoustic devices. Still, such solutions are often expensive, require cumbersome calibration procedures and only allow for AUV localization in an area that is defined by the geometrical arrangement of the transponders. A viable alternative for AUV localization that has recently come to the fore exploits the use of complementary information on the distance from the AUV to a single transponder, together with information provided by on-board resident motion sensors, such as, for example, depth, velocity and acceleration measurements. This concept can be extended to address the problem of relative localization between two AUVs equipped with acoustic sensors for inter-vehicle range measurements. Motivated by these developments, in this paper, we show that both the problems of absolute localization of a single vehicle and the relative localization of multiple vehicles can be treated using the same mathematical framework, and tailoring concepts of observability derived for nonlinear systems, we analyze how the performance in localization depends on the types of motion imparted to the AUVs. For this effect, we propose a well-defined observability metric and validate its usefulness, both in simulation and by carrying out experimental tests with a real marine vehicle during which the performance of an Extended Kalman Filter state observer is shown to depend on the types of motion imparted to the vehicle.
Using Nighttime Satellite Imagery as a Proxy Measure of Human Well-Being
Authors: Ghosh Tilottama , Anderson Sharolyn , Elvidge Christopher , Sutton Paul
Published: November 2013

Improving human well-being is increasingly recognized as essential for movement toward a sustainable and desirable future. Estimates of different aspects of human well-being, such as Gross Domestic Product, or percentage of population with access to electric power, or measuring the distribution of income in society are often fraught with problems. There are few standardized methods of data collection; in addition, the required data is not obtained in a reliable manner and on a repetitive basis in many parts of the world. Consequently, inter-comparability of the data that does exist becomes problematic. Data derived from nighttime satellite imagery has helped develop various globally consistent proxy measures of human well-being at the gridded, sub-national, and national level. We review several ways in which nighttime satellite imagery has been used to measure the human well-being within nations.
Improved Sustainability of Water Supply Options in Areas with Arsenic-Impacted Groundwater
Authors: McBean Edward , Rajib Mohammad , Rahman Md.
Published: November 2013

The supply of water for rural populations in developing countries continues to present enormous problems, particularly where there is arsenic contamination in the groundwater, as exists over significant parts of Bangladesh. In response, improvements in the sustainability of water supplies are feasible through the use of a combination of water sources wherein rainwater harvesting is employed for a portion of the year. This can potentially reduce the duration of the year during which arsenic-contaminated groundwater is utilized. As demonstrated, a rainwater cistern volume of 0.5 m3 in the Jessore district area of Bangladesh can provide rainwater for periods averaging 266 days of the year, which allows groundwater at 184 µg/L arsenic to be used as a water supply for the remainder of the year. This dual supply approach provides the body burden equivalent to the interim drinking water guideline of arsenic concentration of 50 µg/L for 365 days of the year (assuming the water consumption rate is 4 L/cap/day for a family of five with a rainwater collection area of 15 m2). If the water use rate is 20 L/cap/day, the same cistern can provide water for 150 days of the year; however, although this is insufficient to supply water to meet the body burden equivalent guideline of 50 µg/L. Results are provided also for different rooftop areas, sizes of cisterns and alternative arsenic guidelines [World Health Organization (WHO) and Bangladeshi]. These findings provide useful guidelines on supply options to meet sustainability targets of water supply. However, they also demonstrate that the use of cisterns cannot assist the meeting of the 10 µg/L WHO target arsenic body burden, if the arsenic contamination in the groundwater is high (e.g., at 100 µg/L).
Development of a Web-Based L-THIA 2012 Direct Runoff and Pollutant Auto-Calibration Module Using a Genetic Algorithm
Authors: Jang Chunhwa , Kum Donghyuk , Jung Younghun , Kim Kyoungsoon , Shin Dong , Engel Bernard , Shin Yongchul , Lim Kyoung
Published: November 2013

The Long-Term Hydrology Impact Assessment (L-THIA) model has been used as a screening evaluation tool in assessing not only urbanization, but also land-use changes on hydrology in many countries. However, L-THIA has limitations due to the number of available land-use data that can represent a watershed and the land surface complexity causing uncertainties in manually calibrating various input parameters of L-THIA. Thus, we modified the L-THIA model so that could use various (twenty three) land-use categories by considering various hydrologic responses and nonpoint source (NPS) pollutant loads. Then, we developed a web-based auto-calibration module by integrating a Genetic-Algorithm (GA) into the L-THIA 2012 that can automatically calibrate Curve Numbers (CNs) for direct runoff estimations. Based on the optimized CNs and Even Mean Concentrations (EMCs), our approach calibrated surface runoff and nonpoint source (NPS) pollution loads by minimizing the differences between the observed and simulated data. Here, we used default EMCs of biochemical oxygen demand (BOD), total nitrogen (TN), and total phosphorus-TP (as the default values to L-THIA) collected at various local regions in South Korea corresponding to the classifications of different rainfall intensities and land use for improving predicted NPS pollutions. For assessing the model performance, the Yeoju-Gun and Icheon-Si sites in South Korea were selected. The calibrated runoff and NPS (BOD, TN, and TP) pollutions matched the observations with the correlation (R2: 0.908 for runoff and R2: 0.882–0.981 for NPS) and Nash-Sutcliffe Efficiency (NSE: 0.794 for runoff and NSE: 0.882–0.981 for NPS) for the sites. We also compared the NPS pollution differences between the calibrated and averaged (default) EMCs. The calibrated TN and TP (only for Yeoju-Gun) EMCs-based pollution loads identified well with the measured data at the study sites, but the BOD loads with the averaged EMCs were slightly better than those of the calibrated EMCs. The TP loads for the Yeoju-Gun site were usually comparable to the measured data, but the TP loads of the Icheon-Si site had uncertainties. These findings indicate that the web-based auto-calibration module integrated with L-THIA 2012 could calibrate not only the surface runoff and NPS pollutions well, but also provide easy access to users across the world. Thus, our approach could be useful in providing a tool for Best Management Practices (BMPs) for policy/decision-makers.
Diastereoselectivity in the Staudinger reaction of pentafluorosulfanylaldimines and ketimines
Authors: Penger Alexander , von Hahmann Cortney N , Filatov Alexander S , Welch John T
Published: November 2013

β-Lactams were diastereoselectively formed by the reaction of SF5-containing aldimines, or an SF5-containing ketimine, with benzyloxyketene in a conrotatory ring closure process. Imine formation and cyclization were possible in spite of the acidification of protons on the carbon bound to SF5. The reactions of the aldimines demonstrated very good 1,2-lk diastereoselectivity, however lack of stereochemical control of the C–N ketimine geometry was reflected in the stereochemistry of the product β-lactam. Cyclization of imines with a stereogenic center bearing SF5 was reflected in the 1,2-lk,lk selectivity of the β-lactam.
Little known Orphninae (Coleoptera, Scarabaeidae) collected by the Madagascan expeditions of the California Academy of Sciences
Authors: Frolov Andrey
Published: November 2013

New locality records for Madecorphnus niger Frolov, 2010, M. falcatus Paulian, 1992, M. simplex Frolov, 2010, and Triodontus itremoi Paulian, 1977, are given. Endophallus armature of M. niger Frolov, 2010, is described and illustrated.
Haematopathology diagnosis: Role of multidisciplinary training workshops
Authors: Githang’a Jessie , Hurwitz Nina
Published: November 2013

No related abstract found
Ds. Swart van Leeuwfontein
Authors: Terblanche Etienne
Published: November 2013

No abstract available.
Sella Turcica Atypical Teratoid/Rhabdoid Tumor Complicated with Lung Metastasis in an Adult Female
Authors: Moretti Costanzo , Lupoi Domenico , Spasaro Francesca , Chioma Laura , Di Giacinto Paola , Colicchia Martina , Frajoli Mario , Mocini Renzo , Ulisse Salvatore , Antonelli Manila , Giangaspero Felice , Gnessi Lucio
Published: November 2013

Here we present the case of a 60-year-old woman with a rare sellar region atypical teratoid/rhabdoid tumor (AT/RT), complicated by lung metastasis and treated with neurosurgery, radiotherapy, and chemotherapy. The patient had recurrent headache associated with left cavernous sinus syndrome after a previous endonasal transsphenoidal resection for a presumptive pituitary macroadenoma. Pituitary magnetic resonance imaging showed a tumor regrowth in the original location with a haemorrhagic component involving the left cavernous sinus. A near complete transsphenoidal resection of the sellar mass was performed followed by 3 months of stereotactic radiotherapy. Because of a worsening of the general clinical conditions, respiratory failure, and asthenia, the patient underwent a contrast enhanced computer tomography of the whole body which showed the presence of lung metastasis. The histopathological diagnosis on samples from pituitary and lung tissues was AT/RT. The patient survived 30 months after diagnosis regardless chemotherapy. In the adult, the AT/RT should be considered as a possible rare, aggressive, and malignant neoplasm localized in the sella turcica.
The Osteoblastic and Osteoclastic Interactions in Spinal Metastases Secondary to Prostate Cancer
Authors: Dushyanthen Sathana , Cossigny Davina A.F. , Quan Gerald M.Y.
Published: November 2013

Prostate cancer (PC) is one of the most common cancers arising in men and has a high propensity for bone metastasis, particularly to the spine. At this stage, it often causes severe morbidity due to pathological fracture and/or metastatic epidural spinal cord compression which, if untreated, inevitably leads to intractable pain, neurological deficit, and paralysis. Unfortunately, the underlying molecular mechanisms driving growth of secondary PC in the bony vertebral column remain largely unknown. Further investigation is warranted in order to identify therapeutic targets in the future. This review summarizes the current understanding of PC bone metastasis in the spine, highlighting interactions between key tumor and bone-derived factors which influence tumor progression, especially the functional roles of osteoblasts and osteoclasts in the bone microenvironment through their interactions with metastatic PC cells and the critical pathway RANK/RANKL/OPG in bone destruction.
Crank-Nicolson Quasi-Wavelet Based Numerical Method for Volterra Integro-Differential Equations on Unbounded Spatial Domains
Authors: Luo Man , Xu Da , Li Limei
Published: November 2013

The numerical solution of a parabolic Volterra integro-differential equation with a memory term on a one-dimensional unbounded spatial domain is considered. A quasi-wavelet based numerical method is proposed to handle the spatial discretisation, the Crank-Nicolson scheme is used for the time discretisation, and second-order quadrature to approximate the integral term. Some numerical examples are presented to illustrate the efficiency and accuracy of this approach.
Understanding global secondary organic aerosol amount and size-resolved condensational behavior
Authors: D'Andrea S. D. , Häkkinen S. A. K. , Westervelt D. M. , Kuang C. , Levin E. J. T. , Kanawade V. P. , Leaitch W. R. , Spracklen D. V. , Riipinen I. , Pierce J. R.
Published: November 2013

Abstract. Recent research has shown that secondary organic aerosols (SOA) are major contributors to ultrafine particle growth to climatically relevant sizes, increasing global cloud condensation nuclei (CCN) concentrations within the continental boundary layer (BL). However, there are three recent developments regarding the condensation of SOA that lead to uncertainties in the contribution of SOA to particle growth and CCN concentrations: (1) while many global models contain only biogenic sources of SOA (with annual production rates generally 10–30 Tg yr−1), recent studies have shown that an additional source of SOA around 100 Tg yr−1 correlated with anthropogenic carbon monoxide (CO) emissions may be required to match measurements. (2) Many models treat SOA solely as semi-volatile, which leads to condensation of SOA proportional to the aerosol mass distribution; however, recent closure studies with field measurements show nucleation mode growth can be captured only if it is assumed that a significant fraction of SOA condenses proportional to the Fuchs-corrected aerosol surface area. This suggests a very low volatility of the condensing vapors. (3) Other recent studies of particle growth show that SOA condensation deviates from Fuchs-corrected surface-area condensation at sizes smaller than 10 nm and that size-dependent growth rate parameterizations (GRP) are needed to match measurements. We explore the significance of these three findings using GEOS-Chem-TOMAS global aerosol microphysics model and observations of aerosol size distributions around the globe. The change in the concentration of particles of size Dp > 40 nm (N40) within the BL assuming surface-area condensation compared to mass-distribution net condensation yielded a global increase of 11% but exceeded 100% in biogenically active regions. The percent change in N40 within the BL with the inclusion of the additional 100 Tg SOA yr−1 compared to the base simulation solely with biogenic SOA emissions (19 Tg yr−1) both using surface area condensation yielded a global increase of 13.7%, but exceeded 50% in regions with large CO emissions. The inclusion of two different GRPs in the additional-SOA case both yielded a global increase in N40 of < 1%, however exceeded 5% in some locations in the most extreme case. All of the model simulations were compared to measured data obtained from diverse locations around the globe and the results confirmed a decrease in the model-measurement bias and improved slope for comparing modeled to measured CCN number concentration when non-volatile SOA was assumed and the extra SOA was included.
Amino acid composition and δ15N of suspended matter in the Arabian Sea: implications for organic matter sources and degradation
Authors: Gaye B. , Nagel B. , Dähnke K. , Rixen T. , Lahajnar N. , Emeis K.-C.
Published: November 2013

Abstract. Sedimentation in the ocean is fed by large aggregates produced in the surface mixed layer that sink rapidly through the water column. These particles sampled by sediment traps have often been proposed to interact by disaggregation and scavenging with a pool of fine suspended matter with very slow sinking velocities and thus a long residence time. We investigated the amino acid (AA) composition and stable nitrogen isotopic ratios of suspended matter (SPM) sampled during the late SW monsoon season in the Arabian Sea and compared them to those of sinking particles to understand organic matter degradation/modification during passage through the water column. We found that AA composition of mixed layer suspended matter corresponds more to fresh plankton and their aggregates, whereas AA composition of SPM in the sub-thermocline water column deviated progressively from mixed layer composition. We conclude that suspended matter in deep waters and in the mixed layers of oligotrophic stations is dominated by fine material that has a long residence time and organic matter that is resistant to degradation. SPM in areas of high primary productivity is essentially derived from fresh plankton and thus has a strong imprint of the subsurface nitrate source, whereas SPM at oligotrophic stations and at subthermocline depths appears to exchange amino acids and nitrogen isotopes with the dissolved organic carbon (DOC) pool influencing also the δ15N values.
DEFINING PRIVATE PROPERTY INTERESTS IN AMERICA’S NEW ECONOMIC REALITY: THE CASE FOR THE PRIMACY OF FEDERAL LAW IN TAKINGS LITIGATION
Authors: Allen Laura E.
Published: November 2013

DEFINING PRIVATE PROPERTY INTERESTS IN AMERICA’S NEW ECONOMIC REALITY: THE CASE FOR THE PRIMACY OF FEDERAL LAW IN TAKINGS LITIGATION
LOGIC OR PUBLIC POLICY: SHOULD “CONFIRMATORY STATEMENTS” BE ACTIONABLE UNDER RULE 10b-5?
Authors: Keegan Sean
Published: November 2013

LOGIC OR PUBLIC POLICY: SHOULD “CONFIRMATORY STATEMENTS” BE ACTIONABLE UNDER RULE 10b-5?
Bowel Endometriosis with Hemoperitoneum Complicating Pregnancy
Authors: De Vincenzo Rosa , Zannoni Gian Franco , Ricci Caterina , Conte Carmine , Masciullo Valeria
Published: November 2013

Case Report

We report a case of bowel endometriosis complicated by spontaneous hemoperitoneum and miscarriage in a 33-year-old primigravida at the 24th week of gestation. An emergency laparotomy showed spontaneous rupture of the left uterine artery and bowel wall endometrioma. Artery suture, bowel resection and cesarean section on demised fetus were performed.

Conclusions

Although pregnancy may have beneficial effects on endometriosis, rare but significant endometriosis-associated pregnancy complications may also occur.
Importancia del Derecho de Acceso a la Información
Authors: Valencia Gilma Agurcia
Published: November 2013

El derecho de Acceso a la Información pública es necesario para garantizar los derechos a la libertad de opinión y ex­presión que recogen la Declaración Uni­versal de los Derechos Humanos de la Or­ganización de Naciones Unidas, así como otras declaraciones de derechos humanos y muchas Constituciones de diversos países; se considera como un instrumento para promover la participación ciudadana en la gestión pública ya que sin acceso a la información pública no puede haber participación política efectiva. El acceso a la información permite a las personas exa-minar las acciones de su gobierno y cons-tituye una base necesaria para el debate informado sobre esas acciones. A partir de la aprobación y vigencia de la Ley de Transparencia y Acceso a la In­formación Pública (LTAIP) y la creación del Instituto de Acceso a la Información Pública (IAIP) como órgano garante de la aplicación de la Ley, este derecho está reconocido expresamente en nuestra le-gislación secundaria. DOI: http://dx.doi.org/10.5377/lrd.v32i0.1250 Revista de Derecho, Vol. 32, Nº 1, Año 2011: 29-47
Simultaneous Determination of Floctafenine and its Hydrolytic Degradation Product Floctafenic Acid Using Micellar Liquid Chromatography with Applications to Tablets and Human Plasma
Authors: Walash Mohamed I , Belal Fathalla , El-Enany Nahed , Eid Manal , El-Shaheny Rania N
Published: November 2013

A stability-indicating micellar liquid chromatography (MLC) method was developed and validated for the assay of floctafenine (FLF) in the presence of its degradation product and main metabolite, floctafenic acid (FLA). The analysis was carried out on a CLC Shim-Pack octyl silane (C8) column (150 × 4.6 mm id, 5 μm particle size) using a micellar mobile phase consisting of 0.15 M sodium dodecyl sulfate, 10% n-propanol, and 0.3% triethylamine in 0.02 M orthophosphoric acid (pH = 3). The mobile phase was pumped at a flow rate of 1.0 mL/min with UV detection at 360 nm. The method showed good linearity for FLF and FLA over the concentration ranges of 0.5–25.0 and 0.4–10.0 μg/mL, with LODs of 0.16 and 0.12 μg/mL, respectively. The developed method was successfully applied to the determination of FLF in commercial dispersible tablets, with mean recovery of 98.87 ± 1.37%. Also, the proposed method was specific for the analysis of FLF in presence of the co-formulated drug thiocolchicoside in laboratory-prepared tablets, with mean recovery of 100.50 ± 1.07%. Statistical comparison of the results obtained by the proposed MLC method with those obtained by a comparison method showed good agreement. Moreover, the method was extended to study the degradation behavior of FLF under different International Conference on Harmonization recommended conditions such as alkaline, acidic, oxidative, thermal, and photolytic. The method was further applied for direct determination of FLA as the main metabolite of FLF in human plasma without prior extraction steps, with mean recovery of 110.50 ± 6.5%.
Development and Validation of a Liquid Chromatography Method for the Simultaneous Determination of Eight Water-Soluble Vitamins in Multivitamin Formulations and Human Urine
Authors: Patil Suyog S , Srivastava Ashwini K
Published: November 2013

A simple, precise, and rapid RPLC method has been developed without incorporation of any ion-pair reagent for the simultaneous determination of vitamin C (C) and seven B-complex vitamins, viz, thiamine hydrochloride (B1), pyridoxine hydrochloride (B6), nicotinamide (B3), cyanocobalamine (B12), folic acid, riboflavin (B2), and 4-aminobenzoic acid (Bx). Separations were achieved within 12.0 min at 30°C by gradient elution on an RP C18 column using a mobile phase consisting of a mixture of 15 mM ammonium formate buffer and 0.1% triethylamine adjusted to pH 4.0 with formic acid and acetonitrile. Simultaneous UV detection was performed at 275 and 360 nm. The method was validated for system suitability, LOD, LOQ, linearity, precision, accuracy, specificity, and robustness in accordance with International Conference on Harmonization guidelines. The developed method was implemented successfully for determination of the aforementioned vitamins in pharmaceutical formulations containing an individual vitamin, in their multivitamin combinations, and in human urine samples. The calibration curves for all analytes showed good linearity, with coefficients of correlation higher than 0.9998. Accuracy, intraday repeatability (n = 6), and interday repeatability (n = 7) were found to be satisfactory.
IDEXX SNAP® Beta-Lactam ST Validation for Penicillin G Detection
Authors: Waldron Travis T
Published: November 2013

IDEXX has produced a robust and improved rapid test kit optimized to detect penicillin G in a variety of milk matrixes. The SNAP® Beta-Lactam ST Test Kit is designed to be run without the use of a heat block. The new test is optimized to ensure a detection capability for penicillin G that is at or below the European Union maximum residue limit of 4 parts per billion. The test can be used with commingled cow milk, commingled goat milk, commingled sheep milk, and reconstituted whole fat powdered milk. The SNAP Beta-Lactam ST Test Kit contains all the items necessary to run and interpret the test in a single package. No heat block or reader is required. The results can be read visually or with an IDEXX SNAPshot or SNAPshot DSR Reader. The total assay time is approximately 7 minutes.
Simultaneous Determination of Allura Red and Ponceau 4R in Drinks with the Use of Four Derivative Spectrophotometric Methods and Comparison with High-Performance Liquid Chromatography
Authors: Turak Fatma , Ozgur Mahmure Ustun
Published: November 2013

Four simple, rapid, sensitive, and accurate spectrophotometric methods were developed for the simultaneous determination of Allura Red (AR) and Ponceau 4R (P) without previous chemical separation. The first method, derivative spectrophotometry, depends on first derivative spectrophotometry with zero-crossing and peak-to-base measurement. The second method, derivative ratio spectrophotometry, uses the first derivative of the ratio spectra. The ratio spectra are obtained by dividing the absorption spectra of a binary mixture by that of one of the components. The third method, differential derivative spectrophotometry, is based on the measurement of the difference absorptivities derivatized in the first order of a sample extract in 0.1 M NaOH relative to that of an equimolar solution in 0.1 M HCI. The fourth method, based on the compensation technique, is presented for the derivative spectrophotometric determination of binary mixtures with overlapping spectra by using ratios of the derivative maximum or minimum; the exact compensation of either component in the mixture can be achieved, followed by its determination. All the proposed methods were successfully applied to the determination of the colorants in their laboratory mixtures and granulated drinks without any interference by the ingredients. AR and P showed good linearity, with regression coefficients of 0.9994–0.9999. The LOD and LOQ values ranged from 0.059 to 0.102 and 0.198 to 0.341 μg/mL, respectively. The intraday and interday precision tests produced good RSD values (<1.37%); recoveries ranged from 98.75 to 100.37% for all four methods. The common ingredients and additives did not interfere in the AR and P determination. The results of the proposed methods were statistically compared with the results of an HPLC method given in the literature (Nordic Committee on Food Analysis; NMKL 130) at the 95% confidence level by Student's t-test and the variance ratio F-test. No statistically significant difference was found among these methods.
A Novel Standardized Oxygen Radical Absorbance Assay for Evaluating Antioxidant Natural Products
Authors: Osakwe Odilia Nwadiche , Siegel Andre
Published: November 2013

Functional and quantitative evaluation of analytes in crude extracts or semipure mixtures has been considered challenging due to variation in generated results. Some of the drawbacks have been linked to the texture, form, and content of the samples. The crude extracts contain multiple components and, in oxygen radical absorbance capacity (ORAC) assays, have exhibited complex reaction kinetics due to interference or matrix effect. The conventional ORAC assay utilized a single dilution factor that brought about a wide CV difference (60–110%) in antioxidant activity for each extract compared to other dilution factors applied. Due to precision errors introduced from these extremely high CV% differences, determination of antioxidant capacity based on a single dilution may introduce discrepant results. A novel standardized ORAC (SORAC) assay for the determination of antioxidant capacity of dietary plant extracts is described in this study. Using the SORAC assay, positive linear correlations (R2 = 0.95–0.99) were obtained for the sample extracts tested when a multiple dilution strategy was applied. Thus, on the strength of our observations, SORAC has been proposed as an effective tool for assessing antioxidant analytes in a biological matrix. This technique could also be modified for use in other bioanalytical platforms concerned with the analyte matrix effect.
Certification of Elements in and Use of Standard Reference Material 3280 Multivitamin/Multielement Tablets
Authors: Turk Gregory C , Sharpless Katherine E , Cleveland Danielle , Jongsma Candice , Mackey Elizabeth A , Marlow Anthony F , Oflaz Rabia , Paul Rick L , Sieber John R , Thompson Robert Q , Wood Laura J , Yu Lee L , Zeisler Rolf , Wise Stephen A , Yen James H , Christopher Steven J , Day Russell D , Long Stephen E , Greene Ella , Harnly James , Ho I-Pin , Betz Joseph M
Published: November 2013

Standard Reference Material 3280 Multivitamin/ Multielement Tablets was issued by the National Institute of Standards and Technology in 2009, and has certified and reference mass fraction values for 13 vitamins, 26 elements, and two carotenoids. Elements were measured using two or more analytical methods at NIST with additional data contributed by collaborating laboratories. This reference material is expected to serve a dual purpose: to provide quality assurance in support of a database of dietary supplement products and to provide a means for analysts, dietary supplement manufacturers, and researchers to assess the appropriateness and validity of their analytical methods and the accuracy of their results.
Choline in Infant Formula and Adult Nutritionals by Ion Chromatography and Suppressed Conductivity: First Action 2012.20
Authors: Oates Kassandra , Chen Lillian , De Borba Brian , Mohindra Deepali , Rohrer Jeffrey , Dowell Dawn
Published: November 2013

Single-laboratory validation (SLV) data from a method for the determination of choline in infant formula and adult nutritionals by ion chromatography (IC) and suppressed conductivity were generated and presented to the Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) Expert Review Panel (ERP) at the AOAC Annual Meeting held in Las Vegas, NV, during September 30 to October 3, 2012. The ERP reviewed the data and concluded that the data met the standard method performance requirements (SMPRs) established and approved the method as AOAC Official First Action. At the ERP's request, a second, full SLV was performed on 17 SPIFAN matrixes that included fortified and placebo products. Prior to IC analysis, microwave-assisted acid hydrolysis was used to digest and release bound choline from powder and ready-to-feed (RTF) infant formula and adult nutritional samples. Following hydrolysis, separation of choline from common cations was achieved on a Thermo ScientificTM DionexTM IonPacTM CS19 column followed by suppressed conductivity detection. Total choline was measured and reported as the choline ion in mg/100 g reconstituted material or RTF as-is. The system was calibrated over the analytical range specified in the SMPR (2–250 mg/100 g). Recoveries of spiked samples at 50 and 100% of the fortified choline amounts ranged from 93.1 to 100.7% with RSDs ≤6.7% for product containing <2 mg/100 g and ≤4.1% for product containing 2–100 mg/100 g. Accuracy for the National Institute of Standards and Technology Standard Reference Material 1849a was determined over a 6-day interval and found to be 10.2 ± 0.2 mg/100 g calculated as the reconstituted powder with an RSD of 1.8%. The LOD was determined to be 0.009, and the LOQ 0.012 mg/100 g, well below the SMPR requirements of 0.7 and 2 mg/100 g, respectively. Repeatability RSDs over the range of the assay (2–200 mg/100 g) ranged from 1.0 to 5.93%
Choline in Infant Formula and Adult/Pediatric Nutritional Formula by Ultra High-Performance Liquid Chromatography/Tandem Mass Spectrometry: AOAC First Action 2012.18
Authors: Martin Frederic , Gimenez Catherine , Fontannaz Patric , Kilinc Tamara , Campos-Giménez Esther , Dowell Dawn
Published: November 2013

The method described below is for the determination of choline in infant formula and adult/pediatric nutritional formula by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The single-laboratory validation data were submitted to the Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) Expert Review Panel (ERP) for review at the AOAC INTERNATIONAL Annual Meeting held September 30 to October 3, 2012 in Las Vegas, NV. The ERP determined that the data reviewed met the standard method performance requirements set by SPIFAN, and the method was approved as AOAC Official First Action. The analytical range was found to be between 0.16 and 3.2 μg/mL. The recovery rates were within 80–120% at 50 and 100% of native levels for all samples. Repeatability precision (RSDr) was <3%, with intermediate reproducibility (RSDir) no higher than 4%.
Determination of Vitamins A and E in Infant Formula and Adult/Pediatric Nutritional Formula by HPLC with UV and Fluorescence Detection: First Action 2012.09
Authors: Thompson Linda Butler , Schimpf Karen , Baugh Steve
Published: November 2013

The method presented is for quantification of α-tocopherol (vitamin E), vitamin E acetate, vitamin A acetate, and vitamin A palmitate in infant formula and adult/pediatric nutritionals. The entire lipid fraction, including vitamins A and E, is extracted from product with iso-octane after products are mixed with methanol, which precipitates proteins and disrupts micelles freeing lipids for extraction. Vitamin A palmitate, vitamin A acetate, and vitamin E acetate are separated from α-tocopherol on a 3 cm silica column with a 1% methylene chloride, 0.06% isopropanol in iso-octane mobile phase; eluted onto a 20 cm silica column; and, after a column switch, further separated on the 20 cm column before UV detection at 325 nm (vitamin A palmitate and vitamin A acetate) and 285 nm (vitamin E acetate). α-Tocopherol is further separated from other extraneous compounds on the 3 cm silica column and detected by fluorescence at excitation and emission wavelengths of 295 and 330 nm, respectively. Quantification limits in ready-to-feed products were estimated to be 80 IU/L for vitamin A palmitate, 207 International Units (IU)/L for vitamin A acetate, 2.4 mg/L for vitamin E acetate, and <0.15 mg/L for α-tocopherol. Over-spike recoveries and intermediate precision averaged 100.4 and 2.09% RSD for vitamin A palmitate, 100.4 and 1.52% RSD for vitamin E acetate, and 99.6 and 3.02% RSD for α-tocopherol. Vitamin A acetate spike recovery data averaged 96.6%, and the intermediate precision for the only product fortified with vitamin A acetate was 2.75% RSD.
Characterization of Volatile Constituents from Origanum onites and Their Antifungal and Antibacterial Activity
Authors: Altintas Ayhan , Tabanca Nurhayat , Tyihák Erno , Ott Péter G , Móricz Ágnes M , Mincsovics Emil , Wedge David E
Published: November 2013

Essential oils obtained by hydrodistillation (HD) and microwave-assisted HD (MWHD) of Origanum onites aerial parts were analyzed by GC and GC/MS. Thirty-one constituents representing 98.6% of the water-distilled oil and 52 constituents representing 99.6% of the microwave-distilled oil were identified. Carvacrol (76.8% HD and 79.2% MWHD) and thymol (4.7% HD and 4.4% MWHD) were characterized as major constituents in both essential oils. Separation of carvacrol and thymol was achieved by overpressured layer chromatography. HPTLC and TLC separations were also compared. Essential oils were evaluated for antifungal activity against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae, and C. gloeosporioides using a direct overlay bioautography assay. Furthermore, main oil components carvacrol and thymol were then evaluated for antifungal activity; only carvacrol demonstrated nonselective antifungal activity against the three Colletotrichum species. Thymol and carvacrol were subsequently evaluated in a 96-well microdilution broth assay against Phomopsis obscurans, Fusarium oxysporum, three Colletotrichum species, and Botrytis cinerea. No activity was observed against any of the three Colletotrichum species at or below 30 μM. However, thymol demonstrated antifungal activity and produced 31.7% growth inhibition of P. obscurans at 120 h and 0.3 μM, whereas carvacrol appeared inactive. Thymol and carvacrol at 30 μM showed 51.5 and 36.9% growth inhibition of B. cinerea at 72 h. The mechanism of antibacterial activity was studied in a bioautography-based BioArena system. Thymol and carvacrol showed similar inhibition/killing effect against Bacillus subtilis soil bacteria; the action could be enhanced by the formaldehyde generator and transporter copper(II) ions and could be decreased in the presence of L-arginine, a formaldehyde capturer. Results indicated that Origanum essential oils and its major components thymol and carvacrol appear to generate antimicrobial activity through a mechanism of action where formaldehyde and its reaction products are produced.
Applications of Novel Direct Bioautography Tests for Analysis of Antimicrobials: A Review
Authors: Grzelak Edyta M , Jesionek Wioleta , Majer-Dziedzic Barbara , Choma Irena M
Published: November 2013

TLC coupled to direct bioautography detection can be applied to the analysis of various antimicrobial agents in complex matrixes. Because of the lack of commercially available microbiological detection methods, two direct bioautography tests were developed in our laboratory to be used after TLC separation. One method was based on Gram-positive bacteria, Bacillus subtilis, and the other on Gram-negative bacteria, Escherichia coli. These tests can be used for detection and determination of wide spectrum of antimicrobials as well as for other, nontypical purposes, such as choosing the best sample preparation method before the analysis. Some of the more interesting applications of the newly developed tests are described in this paper.
Chemistry and Biological Activities of Tanacetum chiliophyllum var. oligocephalum Extracts
Authors: Polatoğlu Kaan , Karakoç Ömer Cem , Demirci Fatih , Gökçe Ayhan , Gören Nezhun
Published: November 2013

Tanacetum chiliophyllum (Fisch. & Mey.) var. oligocephalum (D.C.) Sosn. collected in Turkey was subjected to phytochemical and biological evaluations in this study. Pure compounds were obtained from ethyl acetate extracts of the stems of the plant material. Structures of isolated compounds were determined using spectral methods. Seven known flavones, i.e., 5-hydroxy-3′,4′,6,7-tetramethoxyflavone, eupatilin (6-hydroxyluteolin-6,3′,4′-trimethylether), cirsimaritin (scuttellarin-6,7-dimethylether), cirsilineol, 5–hydroxy-3′,4′,7-trimethoxy flavone, desmethoxy-centaureidin, and jaceosidin and one known triterpene, taraxasterol acetate, were identified from the ethyl acetate extracts. The first seven compounds, as well as the ethyl acetate and methanol extracts, were also investigated for their insecticidal, antimicrobial, and 1,1-diphenyl-2-picrylhydrazil radical (DPPH)-scavenging activities. The insecticidal contact toxicity of the extracts were evaluated on Sitophilus granarius. The ethyl acetate (81.8%) and methanol (88.4%) extracts of T. chiliophyllum var. oligocephalum showed high toxicity against this pest. Most promising antimicrobial activity was observed for ethyl acetate extracts of the stems against Bacillus cereus. This extract showed the same inhibition concentration (125 μL/mg) with the positive control chloramphenicol. The ethyl acetate (91.9%) and methanol (93%) extracts of the stems showed significant DPPH-scavenging activity compared with the positive controls α-tocopherol (94.5%) and butylated hydroxytoluene (92.9%) at 10 mg/mL concentration. Among the isolated compounds, the highest DPPH-scavenging activity was observed for jaceosidin at 1 mg/mL concentration (81.5%).
Distribution of Low-Density Lipoprotein and High-Density Lipoprotein Subclasses in Patients With Sarcoidosis
Authors: Vekic Jelena , Zeljkovic Aleksandra , Jelic-Ivanovic Zorana , Spasojevic-Kalimanovska Vesna , Spasic Slavica , Videnovic-Ivanov Jelica , Ivanisevic Jasmina , Vucinic-Mihailovic Violeta , Gojkovic Tamara
Published: November 2013

Context.—Systemic inflammatory diseases are associated with proatherogenic lipoprotein profile, but there is a lack of information regarding overall distributions of lipoprotein subclasses in sarcoidosis.

Objective.—To investigate whether patients with sarcoidosis have altered distributions of plasma low-density lipoprotein (LDL) and high-density lipoprotein (HDL) particles.

Design.—Seventy-seven patients with biopsy-proven sarcoidosis (29 with acute and 48 with chronic sarcoidosis) treated with corticosteroids and 77 age- and sex-matched controls were included in the study. Low-density lipoprotein and HDL subclasses were determined by gradient gel electrophoresis, while inflammatory markers and lipid parameters were measured by standard laboratory methods.

Results.—Compared to controls, patients had fewer LDL I subclasses (P < .001), but more LDL II and III (P < .001) subclasses. This pattern was evident in both acute and chronic disease groups. Patients also had smaller HDL size (P < .001) and higher proportions of HDL 2a (P = .006) and 3a particles (P = .004). Patients with chronic sarcoidosis had smaller LDL size than those with acute disease (P = .02) and higher proportions of HDL 3a subclasses (P = .04) than controls. In acute sarcoidosis, relative proportions of LDL and HDL particles were associated with levels of inflammatory markers, whereas in chronic disease an association with concentrations of serum lipid parameters was found.

Conclusions.—The obtained results demonstrate adverse lipoprotein subfraction profile in sarcoidosis with sustained alterations during disease course. Evaluation of LDL and HDL particles may be helpful in identifying patients with higher cardiovascular risk, at least for prolonged corticosteroid therapy due to chronic disease course.