@article {2271, title = {Behavior of interacting species in vacancy affinity capillary electrophoresis described by mass balance equation}, journal = {Electrophoresis}, volume = {29}, number = {16}, year = {2008}, note = {ISI Document Delivery No.: 343MCTimes Cited: 0Cited Reference Count: 42Sun, Ying Fang, Ning Chen, David D. Y.}, month = {Aug}, pages = {3333-3341}, type = {Article}, abstract = {Vacancy ACE (VACE) is one of the ACE methods, and has been used to study binding interactions between different biomolecules. Thermodynamic binding constants can be estimated with nonlinear regression methods. With a highly efficient computer simulation program (SimDCCE), it is possible to demonstrate the detailed behaviors of each species during the interaction process under different conditions. In this work, thirteen scenarios in four different combinations of migration orders of the free protein, free drug, and complex formed are studied. The detailed interaction process between protein and ligand is discussed and illustrated based on the mass balance equation, also called mass transfer equation. By properly setting the parameters in the simulation model, the influence of different factors during the interaction process can be well understood.}, keywords = {affinity capillary electrophoresis, binding constant, COMPUTER-SIMULATION, CONSTANTS, DRUG-PROTEIN-BINDING, equation, EXPERIMENTAL VALIDATION, FRONTAL ANALYSIS, HUMAN-SERUM-ALBUMIN, HUMMEL-DREYER, mass balance, method, PERFORMANCE LIQUID-CHROMATOGRAPHY, vacancy affinity capillary electrophoresis, WALL ADSORPTION, ZONE-ELECTROPHORESIS}, isbn = {0173-0835}, url = {://000258856900008}, author = {Sun, Y. and Fang, N. and Chen, D. D. Y.} } @article {1230, title = {Separation of porphyrin-based photosensitizer isomers by laser-induced fluorescence capillary electrophoresis}, journal = {Electrophoresis}, volume = {26}, number = {20}, year = {2005}, note = {ISI Document Delivery No.: 982VMTimes Cited: 3Cited Reference Count: 43}, month = {Oct}, pages = {3861-3868}, type = {Article}, abstract = {Methods for the separation of photosensitizer isomers, such as benzoporphyrin derivative monoacid, benzoporphyrin ethyl monoacid, 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a, diethyleneglycol diester benzoporphyrin derivative, tin ethyl etiopurpurin, and phthalocyanine tetrasulfonate, have been systematically developed by CE. Detection was accomplished by UV absorption at 214 nm or by LIF with excitation at 442/488 nm and emission at 690 nm. The effects of three major experimental parameters of buffer types, organic solvents, and surfactant additives are described. The optimized separation conditions were determined so as to provide satisfactory separation efficiency and analysis time. The methods are shown to be suitable for the separation and determination of porphyrin and phthalocyanines regioisomers, diastereoisomers, and enantiomers.}, keywords = {chiral additives, CHLORIN, DERIVATIVES, EFFICACY, ENANTIOMERS, FLUORESCENCE DETECTION, FRACTION, LIGHT, PANCREATIC-CANCER CELLS, PERFORMANCE LIQUID-CHROMATOGRAPHY, pharmacokinetics, PHOTODYNAMIC THERAPY, PHTHALOCYANINES, porphyrins, regioisomers}, isbn = {0173-0835}, url = {://000233189700008}, author = {Peng, X. J. and Sternberg, E. and Dolphin, D.} } @article {626, title = {Optimization of cellular nucleotide extraction and sample preparation for nucleotide pool analyses using capillary electrophoresis}, journal = {Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences}, volume = {788}, number = {1}, year = {2003}, note = {ISI Document Delivery No.: 664KCTimes Cited: 12Cited Reference Count: 28}, month = {May}, pages = {103-111}, type = {Article}, abstract = {Cell extraction and further sample preparation for nucleotide pool analysis using capillary electrophoresis was faster and simpler using volatile extraction solvents (e.g. organic solvents and de-ionized water) compared to the commonly applied acids dissolved in water (e.g. perchloric acid and trichloracetic acid). Temperature had to be controlled during the whole sample preparation process to prevent degradation, and extracts had to be cleaned from proteins and other large molecules prior to capillary electrophoretic analysis to improve reproducibility. Capillary electrophoresis using borate and cyclodextrins in the background electrolyte was used for determining 11 cellular nucleotides simultaneously. In order to optimize the assay, 0-100\% acetonitrile, 0-100\% ethanol, and 0-100\% methanol in de-ionized water were applied to extract nucleotides from mouse lymphoma cells, and nucleotide yields, recovery, and reproducibility were compared. The assay met the commonly accepted validation limits for biological fluids, if 20-80\% acetonitrile in water and 40-60\% ethanol in water were used as extraction solvents. (C) 2003 Elsevier Science B.V. All rights reserved.}, keywords = {CELLS, dynamic pH junction, FLUIDS, MIGRATION BEHAVIOR, NUCLEOSIDES, nucleotides, PERFORMANCE LIQUID-CHROMATOGRAPHY, QUANTITATIVE-ANALYSIS, SEPARATION, TISSUES, TRIPHOSPHATES}, isbn = {1570-0232}, url = {://000182059400012}, author = {Grob, M. K. and O{\textquoteright}Brien, K. and Chu, J. J. and Chen, D. D. Y.} } @article {477, title = {Chiral separation of benzoporphyrin derivative mono- and diacids by laser induced fluorescence-capillary electrophoresis}, journal = {Electrophoresis}, volume = {23}, number = {1}, year = {2002}, note = {ISI Document Delivery No.: 513ZATimes Cited: 9Cited Reference Count: 42}, month = {Jan}, pages = {93-101}, type = {Article}, abstract = {A method for the separation of benzoporphyrin derivative mono- and diacid (BPDMA, BPDDA) enantiomers; by laser induced fluorescence-capillary electrophoresis (LIF-CE) has been developed. By using 300 mm borate buffer, pH 9.2, 25 mm sodium cholate and 10\% acetronitrile as electrolyte, +10 kV electrokinetic sampling injection of 2 s and an applied +20 kV voltage across the ends of a 37 cm capillary (30 cm to the detector, 50 mum ID), all six BPD stereoisomers; were baseline-separated within 20 min. Formation constants, free electrophoretic and complexation mobilities with borate and cholate were determined based on dynamic complexation capillary electrophoresis theory. The BPD enantiomers can be quantitatively determined in the range of 10(-2)-10(-5) mg mL(-1). The correlation coefficients (r(2)) of the least-squares linear regression analysis of the BPD enantiomers are in the range of 0.9914-0.9997. Their limits of detection are 2.18-3.5 x 10(-3) mg mL(-1). The relative standard deviations for the separation were 2.90-4.64\% (n = 10). In comparison with high-performance liquid chromatography (HPLC), CE has better resolution and efficiency. This separation method was successfully applied to the BPD enantiomers obtained from a matrix of bovine serum and from liposomally formulated material as well as from studies with rat, dog and human microsomes.}, keywords = {benzoporphyrin derivative mono- and diacids, BORATE COMPLEXATION, capillary electrophoresis, DYNAMIC COMPLEXATION MODEL, MIGRATION BEHAVIOR, PERFORMANCE LIQUID-CHROMATOGRAPHY, PHOTODYNAMIC THERAPY, PHOTOSENSITIZER, porphyrins, QUANTITATIVE DESCRIPTION, SYSTEM, TUMOR, ZONE ELECTROPHORESIS}, isbn = {0173-0835}, url = {://000173410100014}, author = {Peng, X. J. and Sternberg, E. and Dolphin, D.} } @article {361, title = {Determination of arsenic species in a freshwater crustacean Procambarus clarkii}, journal = {Applied Organometallic Chemistry}, volume = {16}, number = {3}, year = {2002}, note = {ISI Document Delivery No.: 521YCTimes Cited: 14Cited Reference Count: 37}, month = {Mar}, pages = {123-132}, type = {Article}, abstract = {The arsenic species present in samples of the crayfish Procambarus clarkii caught in the area affected by the toxic mine-tailing spill at Aznalcollar (Seville, Southern Spain) were analyzed. The total arsenic contents ranged between 1.2 and 8.5 mug g(-1) dry mass (DM). With regard to the different species of arsenic, the highest concentrations were for inorganic arsenic (0.34-5.4 mug g(-1) DM), whereas arsenobetaine, unlike the situation found in marine fish products, was not the major arsenic species (0.16 +/- 0.09 mug g(-1) DM). Smaller concentrations were found of arsenosugars la (0.18 +/- 0.11 mug g(-1) DM), 1b (0.077 +/- 0.049 mug g(-1) DM), 1c (0.080 +/- 0.089 mug g(-1) DM), and 1d (0.14 +/- 0.13 mug g(-1) DM). The presence of two unknown arsenic species was revealed (U1: 0.058 +/- 0.058 mug g(-1) DM; U2: 0.12 +/- 0.12 mug g(-1) DM). No significant differences were seen with respect to the total arsenic contents between the sexes. However, significant differences in the total arsenic contents were revealed between the area affected by the spill and the area not affected, the contents being greater in the affected area. Copyright (C) 2002 John Wiley Sons, Ltd.}, keywords = {arsenic, arsenic species, arsenobetaine, arsenosugars, ATOMIC-ABSORPTION SPECTROMETRY, CADMIUM, crayfish, crustacean, ENVIRONMENT, FISH, freshwater, LEAD, MASS-SPECTROMETRY, PERFORMANCE LIQUID-CHROMATOGRAPHY, SEAFOOD PRODUCTS, WATER MARSH}, isbn = {0268-2605}, url = {://000173868100002}, author = {Devesa, V. and Suner, M. A. and Lai, V. W. M. and Granchinho, S. C. R. and Martinez, J. M. and Velez, D. and Cullen, W. R. and Montoro, R.} } @article {362, title = {Distribution of arsenic species in the freshwater crustacean Procambarus clarkii}, journal = {Applied Organometallic Chemistry}, volume = {16}, number = {12}, year = {2002}, note = {ISI Document Delivery No.: 622PGTimes Cited: 2Cited Reference Count: 25}, month = {Dec}, pages = {692-700}, type = {Article}, abstract = {The concentrations of total arsenic and arsenic species in the complete organism of the crayfish Procambarus clarkii and its various parts (hepatopancreas, tail, and remaining parts) were analyzed in order to discover the distribution of arsenic and its species. With this information it will be possible to establish where the chemical forms of this metalloid tend to accumulate and what risks may derive from the contents and species present in the edible parts of this crustacean. The total arsenic content in the complete organism and in the various parts analyzed ranged from 2.5 to 12 mug g(-1) dry mass (DM), with inorganic arsenic representing 18 to 34\% of total arsenic. The arsenical composition varied according to the part of the crayfish considered. The hepatopancreas had the highest levels of total arsenic (9.2-12 mug g(-1) DM) and inorganic arsenic (2.7-3.2 mug g(-1) DM). The tail (edible part) had the lowest levels of both total arsenic (2.5-2.6 mug g(-1) DM) and inorganic arsenic (0.46-0.64 mug g(-1) DM). The predominant organoarsenical species were the dimethylarsinoylribosides: glycerol riboside in the hepatopancreas, sulfate riboside in the tail, and sulfonate and phosphate ribosides in the remaining parts. Copyright (C) 2002 John Wiley Sons, Ltd.}, keywords = {arsenic, arsenic species, arsenosugars, ATOMIC-ABSORPTION SPECTROMETRY, BIOACCUMULATION, crayfish, DIGESTION, ENVIRONMENT, FISH, freshwater, heptopancreas, MASS-SPECTROMETRY, PERFORMANCE LIQUID-CHROMATOGRAPHY, PRODUCTS, SEAFOOD, SPECIATION, tail muscle}, isbn = {0268-2605}, url = {://000179655000002}, author = {Devesa, V. and Suner, M. A. and Lai, V. W. M. and Granchinho, S. C. R. and Velez, D. and Cullen, W. R. and Martinez, J. M. and Montoro, R.} } @article {420, title = {Sample extraction for arsenic speciation}, journal = {Canadian Journal of Analytical Sciences and Spectroscopy}, volume = {47}, number = {4}, year = {2002}, note = {ISI Document Delivery No.: 641DMTimes Cited: 15Cited Reference Count: 47Joint Meetings of EnviroAnalysis 2002/48th International Conference on Analytical Sciences and SpectroscopyMAY 27-30, 2002TORONTO, CANADA}, pages = {109-118}, type = {Proceedings Paper}, abstract = {The standard method used to determine arsenic species in solid samples is by using an extraction method that minimizes any operationally induced changes in chemical form. However, the use of such methods often results in less than complete extraction, with extraction efficiencies ranging from <1\% to 100\% for many types of samples. In this study the effect on extraction efficiency of the variables of total arsenic content, sample type and extraction method (methanol/water vs. simulated gastric conditions) were examined. The arsenic content in plant and deer mouse samples from Yellowknife, NT, as well as commercially available hijiki, an edible alga, and their extracts, was determined. Statistical analysis of the results revealed that extraction efficiencies are lower for both plants and mouse tissues that contain the highest levels of arsenic, and this trend persists in plants even when more exhaustive extraction methods (Le., Soxhlet extraction) are used. When the plant data was examined with respect to taxonomic groupings moss appeared to be extracted less efficiently than most other plants, and sedge and cattail appeared to be extracted most efficiently. An extraction method modeling human gastrointestinal conditions, gastric fluid extraction (GFE), was comparable to methanol/water extraction of plants with respect to amounts extracted and proportions of As(III) and As(V) present. However, methanol/water was used more efficiently to extract arsenic from wet hijiki than the GFE method. It is important to include information about extraction efficiency when discussing speciation of arsenic in a sample.}, keywords = {ACCELERATED SOLVENT-EXTRACTION, arsenobetaine, BIOAVAILABILITY, CANADA, CERTIFIED-REFERENCE-MATERIALS, CONTAMINATED SOILS, ORGANISMS, PERFORMANCE LIQUID-CHROMATOGRAPHY, PLANTS, PLASMA-MASS SPECTROMETRY, TERRESTRIAL}, isbn = {1205-6685}, url = {://000180729200004}, author = {Koch, I. and Hough, C. and Mousseau, S. and Mir, K. and Rutter, A. and Ollson, C. and Lee, E. and Andrewes, P. and Granhchino, S. and Cullen, B. and Reimer, K.} } @article {4852, title = {Antimony species in environmental samples}, journal = {International Journal of Environmental Analytical Chemistry}, volume = {77}, number = {2}, year = {2000}, note = {ISI Document Delivery No.: 335VQTimes Cited: 17Cited Reference Count: 33}, pages = {111-131}, type = {Article}, abstract = {Antimony was extracted from environmental biota samples from Yellowknife, NWT and Meager Creek, BC, Canada. Extraction efficiencies ranged from 0.7 to 37\% for all samples except for a cattail sample, from which 95\% of antimony was extracted. Speciation analysis was carried out by using hydride generation-gas chromatography-atomic absorption spectrometry (HG-GC-AAS). The major antimony species in all samples, including biota extracts and water, was Sb (V). Sb (III) and methylated antimony species were detected in some samples as well. The presence of methylated antimony species in moss from Yellowknife and a water sample from Yellowknife was confirmed by using HG-GC-AAS at a second absorption wavelength, increasing the likelihood that the peaks obtained are due to the presence of antimony compounds. A headspace HG-GC-mass spectrometric (MS) method was developed for the speciation of antimony compounds and this was used to successfully confirm methylantimony species in the headspace following HG of extracts of moss and snail samples from Yellowknife.}, keywords = {ANTIMONY, ATOMIC-ABSORPTION SPECTROMETRY, GENERATION GAS-CHROMATOGRAPHY, HYDRIDE GENERATION, MASS SPECTROMETRY, PERFORMANCE LIQUID-CHROMATOGRAPHY, PLANTS, SCOPULARIOPSIS-BREVICAULIS, snails, SPECIATION, WATERS}, isbn = {0306-7319}, url = {://000088265800002}, author = {Koch, I. and Wang, L. X. and Feldmann, J. and Andrewes, P. and Reimer, K. J. and Cullen, W. R.} } @article {4861, title = {Speciation of key arsenic metabolic intermediates in human urine}, journal = {Analytical Chemistry}, volume = {72}, number = {21}, year = {2000}, note = {ISI Document Delivery No.: 369XXTimes Cited: 187Cited Reference Count: 45}, month = {Nov}, pages = {5172-5177}, type = {Article}, abstract = {Biomethylation is the major human metabolic pathway for inorganic arsenic, and the speciation of arsenic metabolites is essential to a better understanding of arsenic metabolism and health effects. Here we describe a technique for the speciation of arsenic in human urine and demonstrate its application to the discovery of key arsenic metabolic intermediates, monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)), in human urine. The study provides a direct evidence in support of the proposed arsenic methylation pathway in the human. The finding of MMA(III) and DMA(III) in human urine, along with recent studies showing the high toxicity of these arsenicals, suggests that the usual belief of arsenic detoxification by methylation needs to be reconsidered, The arsenic speciation technique is based on ion pair chromatographic separation of arsenic species on a 3-mum particle size column at 50 degreesC followed by hydride generation atomic fluorescence detection. Speciation of MMA(III), DMA(III), arsenite (As-III), arsenate (As-V), monomethylarsonic acid(MMA(V)), and dimethylarsinic acid (DMA(V)) in urine samples is complete in 6 min with detection limits of 0.5-2 mug/L. There is no need for any sample pretreatment. The capability of rapid analysis of trace levels of arsenic species, which resulted in the findings of the key metabolic intermediates, makes the technique useful for routine arsenic speciation analysis required for toxicological and epidemiological studies.}, keywords = {ATOMIC FLUORESCENCE DETECTION, BLACKFOOT DISEASE, DRINKING-WATER, EXCRETION, EXPOSURE, INGESTION, METHYLATION, PERFORMANCE LIQUID-CHROMATOGRAPHY, SEPARATION, TEMPERATURE}, isbn = {0003-2700}, url = {://000165094000012}, author = {Le, X. C. and Lu, X. F. and Ma, M. S. and Cullen, W. R. and Aposhian, H. V. and Zheng, B. S.} } @article {4535, title = {Sample preparation and storage can change arsenic speciation in human urine}, journal = {Clinical Chemistry}, volume = {45}, number = {11}, year = {1999}, note = {ISI Document Delivery No.: 251HUTimes Cited: 70Cited Reference Count: 543rd International Conference on Arsenic Exposure and Health EffectsJUL 12-15, 1998SAN DIEGO, CALIFORNIA}, month = {Nov}, pages = {1988-1997}, type = {Proceedings Paper}, abstract = {Background: Stability of chemical speciation during sample handling and storage is a prerequisite to obtaining reliable results of trace element speciation analysis. There is no comprehensive information on the stability of common arsenic species, such as inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid, dimethylarsinic acid, and arsenobetaine, in human urine. Methods: We compared the effects of the following storage conditions on the stability of these arsenic species: temperature (25, 4, and -20 degrees C), storage time (1, 2, 4, and 8 months), and the use of additives (HCl, sodium azide, benzoic acid, benzyltrimethyl ammonium chloride, and cetylpyridinium chloride). HPLC with both inductively coupled plasma mass spectrometry and hydride generation atomic fluorescence detection techniques were used for the speciation of arsenic. Results: We found that all five of the arsenic species were stable for up to 2 months when urine samples were stored at 4 and -20 degrees C without any additives. For longer period of storage (4 and 8 months), the stability of arsenic species was dependent on urine matrices. Whereas the arsenic speciation in some urine samples was stable for the entire 8 months at both 4 and -20 degrees C, other urine samples stored under identical conditions showed substantial changes in the concentration of As(III), As(V), monomethylarsonic acid, and dimethylarsinic acid. The use of additives did not improve the stability of arsenic speciation in urine. The addition of 0.1 mol/L HCl (final concentration) to urine samples produced relative changes in inorganic As(III) and As(V) concentrations. Conclusions: Low temperature (4 and -20 degrees C) conditions are suitable for the storage of urine samples for up to 2 months. Untreated samples maintain their concentration of arsenic species, and additives have no particular benefit. Strong acidification is not appropriate for speciation analysis. (C) 1999 American Association for Clinical Chemistry.}, keywords = {CARCINOGENESIS, CHEMICAL FORMS, DIMETHYLARSINIC ACID, DRINKING-WATER, EXCRETION, EXPOSURE, MASS-SPECTROMETRIC DETECTION, METABOLITES, METHYLATION PATTERNS, PERFORMANCE LIQUID-CHROMATOGRAPHY}, isbn = {0009-9147}, url = {://000083440300015}, author = {Feldmann, J. and Lai, V. W. M. and Cullen, W. R. and Ma, M. S. and Lu, X. F. and Le, X. C.} } @article {3139, title = {EVALUATION OF MATRIX-ASSISTED LASER DESORPTION/IONIZATION TIME-OF-FLIGHT MASS-SPECTROMETRY FOR THE ANALYSIS OF ORGANOARSENIC COMPOUNDS OF ENVIRONMENTAL INTEREST}, journal = {Biological Mass Spectrometry}, volume = {23}, number = {12}, year = {1994}, note = {ISI Document Delivery No.: PX594Times Cited: 9Cited Reference Count: 45}, month = {Dec}, pages = {749-755}, type = {Article}, abstract = {Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was investigated for arsenic speciation of compounds of environmental interest. It is a very sensitive mass spectrometric technique which can detect as little as 0.3 ng of arsenic or 4 pmol of the arsenical under investigation. This feature suggests that the method could be used for the identification of minor arsenic components in environmental samples, Additional advantages of the technique are its capability of providing molecular ions as well as fragment ions for a variety of arsenicals, and allowing for a certain degree of control in compound fragmentation, by adjusting the N-2 laser power. Quantitative analysis by MALDI-TOF-MS is still considered a highly unreliable procedure since many variables associated with sample preparation and analytical procedure can seriously affect the results.}, keywords = {arsenic, arsenobetaine, ARSENOCHOLINE, COMPOUNDS, CONFIRMATION, desorption, FAST ATOM BOMBARDMENT, IDENTIFICATION, OLIGOSACCHARIDES, PERFORMANCE LIQUID-CHROMATOGRAPHY, SPECIATION}, isbn = {1052-9306}, url = {://A1994PX59400005}, author = {Pergantis, S. A. and Cullen, W. R. and Eigendorf, G. K.} } @article {3092, title = {SPECIATION OF ARSENIC COMPOUNDS BY HPLC WITH HYDRIDE GENERATION ATOMIC-ABSORPTION SPECTROMETRY AND INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY DETECTION}, journal = {Talanta}, volume = {41}, number = {4}, year = {1994}, note = {ISI Document Delivery No.: NJ813Times Cited: 94Cited Reference Count: 45}, month = {Apr}, pages = {495-502}, type = {Article}, abstract = {An arsenic specific detection system utilizing on-line microwave digestion and hydride generation atomic absorption spectrometry (MD/HGAAS) is described for arsenic speciation by using high performance liquid chromatography (HPLC). Both ion exchange chromatography and ion pair chromatography have been studied for the separation of arsenite, arsenate, monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA), and arsenobetaine (AB). When the commonly used mobile phases, phosphate and carbonate buffers at pH 7.5, are used on an anion exchange column, arsenite and AB co-elute. However, selective determination of these two arsenic compounds can be achieved by using the new detection system. Partial separation between arsenite and AB can be achieved by increasing the mobile phase pH to 10.3 and by using a polymer based anion exchange column. The detection limit obtained by using anion exchange chromatography with MD/HGAAS detection is approximately 10 ng/ml (or 200 pg for a 20-mul sample injection) for arsenite, DMAA and AB, 15 ng/ml (or 300 pg) for MMAA, and 20 ng/ml (or 400 pg) for arsenate. Complete separation of the five arsenic compounds is achieved on a reversed phase C18 column by using sodium heptanesulfonate as ion pair reagent. Comparable resolution between chromatographic peaks is obtained by using MD/HGAAS detection and inductively coupled plasma mass spectrometry (ICPMS) detection.}, keywords = {ELEMENT-SPECIFIC DETECTOR, IDENTIFICATION, ION CHROMATOGRAPHY, MUSCLE, ORGANOARSENIC COMPOUNDS, PERFORMANCE LIQUID-CHROMATOGRAPHY, QUANTITATION, REFERENCE MATERIAL, SEPARATION, TRACE-ELEMENTS, WATER}, isbn = {0039-9140}, url = {://A1994NJ81300003}, author = {Le, X. C. and Cullen, W. R. and Reimer, K. J.} }