bluuebunny/crossref_metadata_2025_split huggingface dataset:
VARIATION IN THE CONJUGATED LINOLEIC ACID CONTENT OF THREE TRADITIONAL GREEK CHEESES DURING A 1‐YEAR PERIOD
Authors: ZLATANOS SPIROS , LASKARIDIS KOSTAS 
Published: February 2009

ABSTRACT The fat and fatty acid content of three traditional Greek cheeses were determined monthly for a period of 1 year. The analyzed cheeses, feta, graviera and manouri, are traditional Greek dairy products made exclusively or primarily from sheep milk. In all cheeses, the content of the fatty acids varies during several months, especially the conjugated linoleic acid (CLA) content of feta, graviera and manouri ranged between 0.5 and 0.9, 0.5 and 1.0 and 0.4 and 0.8 g/100 g total fatty acids, respectively. The average content of CLA in graviera and feta was similar (0.75 and 0.72 g/100 g fatty acids, respectively). On the other hand, the CLA content of manouri (0.54 g/100 g fatty acids) was less than that of the other two cheeses. In every case, the analyzed cheeses can be characterized as good or very good CLA sources. PRACTICAL APPLICATIONSNo data exist about the variation in the fatty acid composition of standardized cheeses during the various months of the year. Several investigations were carried out in order to determine the fatty acid composition and especially the conjugated linoleic acid (CLA) content of various kinds of cheese. However, cheeses were produced from milk and it is suggested that the milk composition is affected by seasonal factors. In the present investigation, we tried to find out if the beneficial fatty acid content of cheeses, which were previously found as rich CLA sources, is season dependent. The results of this research are a potential tool for food technologist in order to provide CLA‐enriched diets.
GELATINIZATION BEHAVIOR OF GRAINS AND FLOUR IN RELATION TO PHYSICO‐CHEMICAL PROPERTIES OF MILLED RICE (ORYZA SATIVA L.)
Authors: BOCEVSKA MIRJANA , ALDABAS IMAD , ANDREEVSKA DANICA , ILIEVA VERICA 
Published: February 2009

ABSTRACT Physico‐chemical properties of milled rice grains of 13 japonica varieties were evaluated. The rice varieties differed in appearance. One sample had long grains (6.61 mm), two had short grains (5.27–5.32 mm) and the rest had grains of medium length (5.52–6.55 mm). The shape (length/width) of grains varied from bold (1.58–1.9) to medium (2.06–2.37). The protein content was high in all samples (7.82 to 9.72% on dry mass). Almost all, with exception of one cultivar (Osogovka), which had intermediate amylose content (23.3%), were low amylose varieties (12–19.4% amylose). Their minimum cooking time varied from 17.5 to 22.5 min. Significant correlations (P < 0.05) were established between some physico‐chemical characteristics of evaluated rice cultivars. Elongation during minimum cooking time was correlated with protein content (r = 0.6899), shape (−0.7137), thickness (0.7234) and width (0.9134) of grains. The rice flour paste viscosity correlated significantly with shape (0.6148) and length (0.7353) of grains. On the basis of the established results, it was concluded that appearance of milled rice could be used as indicator for predicting gelatinization behavior: elongation ratio (length after minimum cooking time/length of the grains) of the rice grains and viscosity of rice flour during cooking.PRACTICAL APPLICATIONSResults from this research constitute a useful tool to predict the gelatinization behavior of milled grains and flour of japonica rice varieties, on the basis of grain appearance. The appearance is critical in acceptability of rice varieties by the consumers. The possibility to predict rice grain behavior during cooking on the basis of its appearance could be an additional attribute or market value for consumer choice. The results could be used in selection of rice variety for rice grits or flour production and use in special applications.
Connecting Atmosphere and Wetland: Trace Gas Exchange
Authors: Lafleur Peter M. 
Published: February 2009

AbstractThis article reviews the exchange of carbon dioxide (CO2) and methane (CH4) gases between wetland and atmosphere, with a primary emphasis on ecosystem‐scale fluxes and their environmental controls. It is intended to complement a previous review of wetland energy and water exchanges (Lafleur 2008). It is shown that wetland exchanges of these gases are greatly variable in space and time, especially CH4. Most wetlands appear to be sinks for atmospheric CO2, while almost all are emitters of CH4. The strongest environmental control on the CO2flux is drought, which often determines whether a wetland will be a net sink or source for atmospheric CO2. Due to complex biochemistry and transport mechanisms, methane efflux from wetlands often ranges over several orders of magnitude within a single wetland and among wetlands, making it difficult to quantify the environmental controls on this flux. The magnitude of gas fluxes is not strongly related to wetland type, which implies that modelling of these fluxes should consider wetlands a continuum and attempt to address processes as they vary along this continuum instead of as discrete entities. Although more research is required into the magnitude, variation and controls on trace gas fluxes in all wetland types, some wetlands (tropical and temperate marshes) are particularly understudied.
DNA barcoding discriminates the noxious invasive plant species, floating pennywort (Hydrocotyle ranunculoides L.f.), from non‐invasive relatives
Authors: VAN DE WIEL C. C. M. , VAN DER SCHOOT J. , VAN VALKENBURG J. L. C. H. , DUISTERMAAT H. , SMULDERS M. J. M. 
Published: February 2009

AbstractFloating pennywort (Hydrocotyle ranunculoides L.f.), a member of the plant family Araliaceae originating from North America, is an example of an invasive aquatic species posing serious problems to the management of waterways outside of its original distribution area in Australia and Western Europe. As a consequence, its import was banned in the Netherlands. It can be difficult to distinguish H. ranunculoides from other species of the genus on a morphological basis. In this regard, DNA barcoding may become a good alternative once this could be performed on a routine basis. In this study, we show that it is possible to distinguish H. ranunculoides from a series of closely related congeners by using a single plastid DNA sequence, trnH‐psbA.
Correction of megavoltage cone‐beam CT images of the pelvic region based on phantom measurements for dose calculation purposes
Authors: Aubry Jean‐François , Cheung Joey , Morin Olivier , Gottschalk Alexander , Beaulieu Luc , Pouliot Jean 
Published: February 2009

Megavoltage cone‐beam CT (MVCBCT) is an imaging technology that provides a 3D representation of the patient in treatment position. Because it is a form of x‐ray tomography, MVCBCT images give information about the attenuation coefficients of the imaged tissues, and thus could be used for dose calculation. However, the cupping and missing data artifacts seen on MVCBCT images can cause inaccuracies in dose calculations. To eliminate these inaccuracies, a correction method specific to pelvis imaging and based on phantom measurements has been devised. Pelvis‐shaped water phantoms of three different sizes were designed and imaged with MVCBCT. Three sets of correction factors were created from the artifacts observed in these MVCBCT images by dividing the measured CT number by the predefined CT number for water. Linear interpolation is performed between the sets of correction factors to take into account the varying size of different patients. To compensate for the missing anatomy due to the limited field of view of the MVCBCT system, the MVCBCT image is complemented with the kilovoltage CT (kVCT) image acquired for treatment planning. When the correction method is applied to an anthropomorphic pelvis phantom, the standard deviation between dose calculations performed with kVCT and MVCBCT images is 0.6%, with 98% of the dose points agreeing within . With uncorrected MVCBCT images this percentage falls to 75%. An example of dose calculation performed with a corrected clinical MVCBCT image of a prostate cancer patient shows that changes in anatomy of normal tissues result in variation of the dose distribution received by these tissues. This correction method enables MVCBCT images to be used for the verification of the daily dose distribution for patients treated in the pelvis region.PACS numbers: 87.57.Q‐ Computed tomography, 87.57.cp Artifacts and distortion
Automating the initial physics chart‐checking process
Authors: Furhang Eli E. , Dolan James , Sillanpaa Jussi K. , Harrison Louis B. 
Published: February 2009

The initial physics chart check, an essential quality assurance process, verifies that the physician intent is properly expressed in the treatment plan, the treatment plan is reasonable, and the Record and Verify (RV) system properly captures the plan parameters. In this work the process was automated by characterizing the initial physics chart check as a universal set of steps, compartmentalized into intra‐plan and inter‐plan reviews. The intra‐plan review confirms the diagnosis‐prescription‐plan correlation, and verifies transfer accuracy of the signed treatment plan parameters into the RV system. The inter‐plan review tabulates all RV parameters for similar cases, and highlights outliers. The tabulation of RV parameters for similar cases enables a summation of experience across staff members, and facilitates a comparison using the Statistical Process Control (SPC) formalism. A summary sheet, added to each reviewed chart, automatically documents deviations noted during the review process. Forty‐five patient charts were analyzed using the software. The length of time for the entire initial chart‐checking process was reduced from about an hour to a few minutes. The code developed in this work allows the user to consider the big picture, trusting the software to track details.PACS number 89.20.Bb
Investigation into the use of a MOSFET dosimeter as an implantable fiducial marker
Authors: Kry Stephen F , Price Michael , Wang Zhonglu , Mourtada Firas , Salehpour Mohammad 
Published: February 2009

It may be possible to use a single device to measure the in vivo dose delivered during radiotherapy, as well as to localize the target volume. This potential, as well as the detectors' ability to relate dosimetry and localization, were evaluated using two implantable MOSFET dosimeters placed inside an acrylic pelvic phantom. A wedged‐field photon plan and an eight‐field prostate treatment plan were developed. For each plan, conditions were simulated so that detectors were in their correct positions or slightly displaced to represent patient setup error and/or organ motion. Doses measured by the two detectors after irradiation were compared to those calculated by the treatment planning software. Additionally, using localization software and kilovoltage images of each setup, the displacement of the detectors from their correct locations was calculated and compared to the induced physical displacement. For all alignments and detector positions, measured and calculated doses showed an average disagreement of 2.7%. The detectors were easily visualized radiographically and the induced detector displacements were typically recognized by the localization software to within 0.1 cm. The implantable detector functioned well as both an internal dosimeter and as an internal fiducial marker, and thus may be useful as a clinical tool to localize the target volume and verify dose delivery in vivo.PACS numbers: 87.53.‐j 87.55.‐x
Dose optimization of breast balloon brachytherapy using a stepping HDR source
Authors: Choi Chang Hyun , Ye Sung‐Joon , Parsai E. Ishmael , Shen Sui , Meredith Ruby , Brezovich Ivan A. , Ove Roger 
Published: February 2009

To develop dose optimization schemes of breast balloon brachytherapy using a stepping of HDR source.There is a considerable underdosage (11%–13%) of PTV due to anisotropy of a stationary source in breast balloon brachytherapy. We improved the PTV coverage by varying multiple dwell positions and weights. We assumed that the diameter of spherical balloons varied from 4.0 cm to 5.0 cm, that the PTV was a 1‐cm thick spherical shell over the balloon (reduced by the small portion occupied by the catheter path), and that the number of dwell positions varied from 2 to 13 with 0.25‐cm steps, oriented symmetrically with respect to the balloon center. By assuming that the perfect PTV coverage can be achieved by spherical dose distributions from an isotropic source, we developed an optimization program to minimize two objective functions defined as: (1) the number of PTV‐voxels having more than 10% difference between optimized doses and spherical doses, and (2) the difference between optimized doses and spherical doses per PTV‐voxel.The optimal PTV coverage occurred when applying 8–11 dwell positions with weights determined by the optimization scheme. Since the optimization yields ellipsoidal isodose distributions along the catheter, there is relative skin sparing for cases with source movement approximately tangent to the skin. We also verified the optimization in CT‐based treatment planning systems.Our volumetric dose optimization for PTV coverage showed close agreement to linear or multiple‐points optimization results from the literature. The optimization scheme provides a simple and practical solution applicable to the clinic.PACS number: 87.55.de
Radiation therapy plan checks in a paperless clinic
Authors: Siochi R. Alfredo , Pennington Edward C. , Waldron Timothy J. , Bayouth John E. 
Published: February 2009

Traditional quality assurance checks of a patient's radiation therapy plan involve printing out treatment parameters from the treatment planning system and the “record and verify” (R&V) system and visually checking the information for one‐to‐one correspondence. In a paperless environment, one can automate this process through independent software that can read the treatment planning data directly and compare it against the parameters in the R&V system's database. In addition to verifying the data integrity, it is necessary to check the logical consistency of the data and the accuracy of various calculations. The results are then imported into the patient's electronic medical record. Appropriate workflows must be developed to ensure that no steps of the QA process are missed. This paper describes our electronic QA system (EQS), consisting of in‐house software and workflows. The EQS covers 3D conformal and intensity modulated radiation therapy, electrons, stereotactic radiosurgery, total body irradiation, and clinical set ups with and without virtual simulation. The planning systems handled by our EQS are ADAC Pinnacle and Varian FASTPLAN, while the R&V systems are LANTIS and VARIS. The improvement in our plan check process over the paperless system is described in terms of the types of detected errors. The potential problems with the implementation and use of the EQS, as well as workarounds for data that are not easily accessible through electronic means, are described.PACS numbers: 87.55.Qr, 87.55.tg, 87.55.tm
Automated Quality Assurance for Image‐Guided Radiation Therapy
Authors: Schreibmann Eduard , Elder Eric , Fox Tim 
Published: February 2009

The use of image‐guided patient positioning requires fast and reliable Quality Assurance (QA) methods to ensure the megavoltage (MV) treatment beam coincides with the integrated kilovoltage (kV) or volumetric cone‐beam CT (CBCT) imaging and guidance systems. Current QA protocol is based on visually observing deviations of certain features in acquired kV in‐room treatment images such as markers, distances, or HU values from phantom specifications. This is a time‐consuming and subjective task because these features are identified by human operators. The method implemented in this study automated an IGRT QA protocol by using specific image processing algorithms that rigorously detected phantom features and performed all measurements involved in a classical QA protocol. The algorithm was tested on four different IGRT QA phantoms. Image analysis algorithms were able to detect QA features with the same accuracy as the manual approach but significantly faster. All described tests were performed in a single procedure, with acquisition of the images taking approximately 5 minutes, and the automated software analysis taking less than 1 minute. The study showed that the automated image analysis based procedure may be used as a daily QA procedure because it is completely automated and uses a single phantom setup.PACS numbers: 87.56.Fc
Urinary polycyclic aromatic hydrocarbons and monohydroxy metabolites as biomarkers of exposure in coke oven workers
Authors: Rossella F , Campo L , Pavanello S , Kapka L , Siwinska E , Fustinoni S 
Published: February 2009

Objectives:To assess exposure to polycyclic aromatic hydrocarbons (PAHs) using 13 unmetabolised PAHs (U-PAHs) and 12 monohydroxy metabolites (OHPAHs) in urine, and to compare the utility of these biomarkers.Methods:55 male Polish coke oven workers collected urine spot samples after a workshift. U-PAHs (naphthalene, acenaphtylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene) were determined by automatic solid phase micro-extraction followed by gas chromatography/mass spectrometry (GC/MS). OHPAHs (1- and 2-hydroxynaphthalene, 2- and 9-hydroxyfluorene, 4-, 9-, 3-, 1- and 2-hydroxyphenanthrene, 1-hydroxypyrene, 6-hydroxychrysene, 3-hydroxybenzo[a]pyrene) were determined, after liquid/liquid extraction and derivatisation, by GC/MS.Results:U-PAHs from naphthalene to chrysene were found in 100% of samples, and heavier U-PAHs in 7–22% of samples. OHPAHs up to 1-hydroxypyrene were found in 100% of samples, while 6-hydroxychrysene and 3-hydroxybenzo[a]pyrene were always below the quantification limit. Median naphthalene, phenanthrene, pyrene, chrysene and benzo[a]anthracene levels were 0.806, 0.721, 0.020, 0.032 and 0.035 μg/l, while hydroxynaphthalenes, hydroxyphenanthrenes and 1-hydroxypyrene levels were 81.1, 18.9 and 15.4 μg/l. For each chemical, the ratio between U-PAH and the corresponding OHPAH ranged from 1:26 to 1:1000. Significant correlations between logged values of U-PAHs and OHPAHs, between U-PAHs, and between OHPAHs were found, with Pearson’s r ranging from 0.27 to 0.97.Conclusion:Current analytical techniques allow specific and simultaneous measurement of several urinary determinants of PAHs in humans. The results of these measurements support the use of U-PAHs as biomarkers of exposure and suggest the spectrum of chemicals to be investigated, including carcinogenic chrysene and benzo[a]anthracene, should be widened.
A simplified approach to determine the optimum operating speed on high-speed railway lines
Authors: Öztürk Zübeyde , Öztürk Turgut 
Published: February 2009

In this study, cost–speed relationship for high speed railways was examined and optimum economic speed was investigated. The Eskişehir–Ankara section of the İstanbul–Ankara railway line, which is still under construction, was taken as the sample. This section has been completed and test runs are being conducted. The new line is constructed parallel to the old railway line and the operation speeds and operation forms of the trains on this line are not yet finalized. It is not yet clear what the maximum operation speeds of the trains will be and whether the operation will be restricted to only high speed passenger trains or a combination of passenger and freight trains will be used. Therefore, cost changes associated with speed for both operations were examined in the study. The speed for the lowest cost was investigated for the benefit of the operating institute. The rail line is scheduled to begin operation in 2010, and as such demand estimation values for 2010 and unit cost values of Turkish State Railways (TCDD) were utilized. Only construction and operation costs were analyzed, societal costs were not included in the study. Several costs were formulated independent ofthe speed, whereas the majority of them were formulated and calculated based on speed. Finally, the contribution of each studied cost component, in the total cost, and variations in these costs and total cost for different speeds for both operation conditions were analyzed in this study. It was found that some cost components increased and some decreased as the speed increases. Total cost, which includes all the cost components studied, initially dropped off then rose up as the speed incrementally increases. Minimum cost occurred at 200 km/h in the case of operating with only passenger trains, while it occurred at the second speed level in combined operation (where passenger trains are at the speed of 200 km/h and freight trains are at the speed of 90 km/h).
Rate-dependent fracture modeling of asphalt concrete using the discrete element method
Authors: Kim Hyunwook , Wagoner Michael P. , Buttlar William G. 
Published: February 2009

The discrete element method (DEM) represents a convenient and powerful tool for studying effects of material microstructure on fracture mechanisms in asphalt concrete. In this paper, the rate-dependency of asphalt concrete is investigated using a cohesive zone model with bulk viscoelastic properties combined with bilinear post-peak softening. Details of the constitutive models implemented in the DEM, with particular emphasis on the verification of viscoelastic models, are presented. Experimental test results based on a disk-shaped compact tension test are obtained under different loading rates and those are compared to numerical simulations with the help of the rate-dependent model. Homogeneous and heterogeneous model results are compared, where heterogeneous models are constructed to consider aggregate morphology for particles larger than 1.18 mm. The relative importance of time-dependence and the consideration of material heterogeneity in the simulation of monotonic Mode I fracture tests are demonstrated.
BISTABILITY AND HYSTERESIS IN SYMMETRIC 3D PIECEWISE LINEAR OSCILLATORS WITH THREE ZONES
Authors: FREIRE EMILIO , PONCE ENRIQUE , ROS JAVIER 
Published: February 2009

A degeneration in a two-parameter setting for the focus-center-limit cycle bifurcation of symmetric 3D piecewise linear systems with three zones is studied. The analysis gives a rigorous mathematical explanation for the appearance in piecewise linear oscillators of up to two limit cycles along with a related hysteresis phenomenon.A piecewise linear oscillator, which is a member of the generic Chua's circuit family, is shown to exhibit bistability, that is, coexistence of stable oscillations with a stable steady state. Also, the corresponding hysteresis in the appearance of periodic oscillations is explained. The analytical results included in the paper predict accurately the observed behavior.