bluuebunny/crossref_metadata_2025_split huggingface dataset:
A strategy for the prior processing of high‐resolution mass spectral data obtained from high‐dimensional combined fractional diagonal chromatography
Authors: Valkenborg Dirk , Thomas Grégoire , Krols Luc , Kas Koen , Burzykowski Tomasz 
Published: December 2008

AbstractCombined fractional diagonal chromatography (COFRADIC) is a novel suite of gel‐free technologies for the identification of biomarkers in complex peptide mixtures. For this purpose, reversed‐phase high performance liquid chromatography (HPLC) technology and, in this case, matrix assisted laser desorption /ionization‐ time of flight (MALDI‐TOF) mass spectrometers are extensively used. The particular characteristic of COFRADIC mass spectrometry data is the high number of chromatographic fractions, over which a peptide can be scattered. This can obstruct the quantification of the peptide abundance in the biological sample, which is required for statistical analysis. On the other hand, because of the superior peptide sorting properties of the methodology, the mass spectra become less crowded. Consequently, each peptide appears in a mass spectrum as a series of peaks with peak heights proportional to the probability of occurrence of the isotopic variants of the peptide. In this manuscript, we propose an analysis strategy concerned with the preprocessing of COFRADIC mass spectra prior to a downstream statistical analysis. The preprocessing algorithm produces for each mass spectrum a peptide list by exploiting the characteristic features that should be associated with peaks corresponding to an isotopically resolved cluster of peptide peaks. This reduction step is necessary to facilitate the clustering used in a next step to assemble the validated monoisotopic peptide peaks found over several fractions into a single peptide abundance. To assess the performance of the algorithm, two technical experiments were conducted. The proposed strategy is memory and computationally efficient. Copyright © 2008 John Wiley & Sons, Ltd.
Silicon‐induced cadmium resistance in rice (Oryza sativa)
Authors: Nwugo Chika C. , Huerta Alfredo J. 
Published: December 2008

AbstractSilicon (Si)‐induced cadmium (Cd) tolerance in rice (Oryza sativa L.) was investigated by analyzing Cd uptake, growth, and physiological parameters. Silicon treatments (0.0, 0.2, or 0.6 mM) were added to 6 d–old seedlings, and Cd treatments (0.0 or 5.0 μM) were added to 20 d–old seedlings. Parameters determined included: maximum net CO2 assimilation (Amax), stomatal conductance (gsmax), and transpiration (Emax) rates at varying intercellular CO2 concentrations (Ci). Also measured were chlorophyll fluorescence, growth, and Cd‐uptake parameters. Results showed a Si‐induced inhibition of Cd uptake. However, 0.2 mM or 0.6 mM Si treatment concentrations did not differentially inhibit Cd uptake or differentially alleviate Cd‐induced growth inhibition, despite a significant increase in tissue Si concentration due to 0.6 mM Si treatment compared to 0.2 mM Si treatment. Additionally, photosynthesis and chlorophyll‐fluorescence analysis showed that treatment with Cd significantly inhibited photosynthetic efficiency. Interestingly, the addition of 0.2 mM Si, more so than the addition of 0.6 mM Si, significantly alleviated the inhibitory effects of Cd toxicity on photosynthesis and chlorophyll‐fluorescence parameters. Our results suggest that 0.2 mM Si could be close to an optimum Si‐dose requirement for the alleviation of toxicity symptoms mediated by moderate (5 μM) Cd exposure.
Effects of egg weight on egg quality characteristics
Authors: Şekeroǧlu Ahmet , Altuntaş Ebubekir 
Published: December 2008

AbstractBACKGROUND: The experiment was carried out with total of 270 eggs, which were collected from a brown‐egg layer strain of Lohmann hens reared in a cage system. Collected eggs were categorized according to weight and classified as medium, large, extra‐large or jumbo. The purpose of the study was to determine the effect of egg weight on egg quality characteristics.RESULTS: The darkest shell color scales were noted in jumbo eggs. The redness of egg shell color in the medium egg was significantly lower than that of the other egg sizes (P < 0.05). Egg shell thickness (P < 0.05) was highest in medium egg (0.400 mm) and lowest in extra‐large egg (0.382 mm). Albumen height (AH) was significantly affected by egg weight (EW) (P < 0.01). Yolk height (YH) and yolk index (YI) increased with egg size. Breaking strength was highest in the medium‐weight egg. There were significant positive correlations between EW and AH, EW and YH, EW and YI, EW and yol color, EW and redness (a), but EW had significant negative correlations with ST in overall eggs.CONCLUSION: The darkest shell color (L‐a‐b) was noted in the jumbo egg. Albumen height and yolk height increased with egg weight. Increase in egg weight caused darkness in the yolk color scale. Copyright © 2008 Society of Chemical Industry
Highly selective artificial gel antibodies for detection and quantification of biomarkers in clinical samples. I. Spectrophotometric approach to design the calibration curve for the quantification
Authors: Ghasemzadeh Nasim , Nyberg Fred , Hjertén Stellan 
Published: December 2008

AbstractHigh selectivity of a biomarker is a basic requirement when it is used for diagnosis, prognosis and treatment of a disease. The artificial gel antibodies, which we synthesise by a molecular imprinting method, have this property not only for proteins, but also for bioparticles, such as viruses and bacteria. However, diagnosis of a disease requires not only that the biomarker can be “fished out” from a body fluid with high selectivity, but also that its concentration in the sample can rapidly be determined and preferably by a simple technique. This paper deals primarily with the development of a spectrophotometric method, which is so simple and fast that it can be used with advantage in a Doctor's Office. The development of this method was not straight‐forward. However, by modifications of the performance of these measurements we can now design standard curves in the form of a straight line, when we plot the true (not the recorded “apparent” absorption) against known protein concentrations. In an additional publication (see the following paper in this issue of JSS) we show an application of such a plot: determination of the concentration of albumin in serum and cerebrospinal fluid from patients with neurological disorders to investigate whether albumin is a biomarker for these diseases.
New derivatizing reagent for analysis of diethylene glycol by HPLC with fluorescence detection
Authors: Wu Jiangang , Yuan Jinbin , Liu Qian , Tang Fei , Ding Li , Tan Jun , Yao Shouzhuo 
Published: December 2008

AbstractN‐(2‐Phenyl‐indolyl)‐acetic acid (PIAA), a new fluorescent derivatizing reagent, was used for the determination of diethylene glycol (DEG) by high‐performance liquid chromatography with fluorescence detection. DEG was derivatized to ester by using PIAA in the presence of 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodimide hydrochloride (as dehydrating agent) and 4‐(dimethylamino)pyridine (as base catalyst) in acetonitrile at 60°C for 75 min. The influence of solvent, temperature, catalyst base, concentration of labeling reagent, and couple reagent on the derivatization was investigated. The fluorescence detection was performed with excitation at 340 nm and emission at 377 nm. Baseline separation was obtained on an Ultimate XB‐C18 analytical column with water/acetonitrile gradient elution, good linearity was obtained within 0.5–50 μg/mL with a correlation coefficient of 0.9997. The limit of detection was 0.01 μg/mL (signal‐to‐noise ratio = 3). The method has been successfully applied to determine DEG in toothpaste samples with satisfactory recoveries ranging from 89.0 to 94.9%. The proposed method was shown to be a promising technique for the determination of DEG with high sensitivity.
Chemical fingerprint of Hoodia species, dietary supplements, and related genera by using HPTLC
Authors: Rumalla Chidananda Swamy , Avula Bharathi , Shukla Yatin J. , Wang Yan‐Hong , Pawar Rahul S. , Smillie Troy J. , Khan Ikhlas A. 
Published: December 2008

AbstractA HPTLC method was developed for simple and rapid chemical fingerprint analysis of four Hoodia species, dietary supplements that claim to contain Hoodia gordonii, and plants from genera related to Hoodia. HPTLC was performed on precoated silica 60F254 plates with dichloromethane/methanol/water 75:17:2.2 by volume, as mobile phase. Evaluation of the HPTLC plates was done by using the CAMAG DigiStore2 digital system with winCATS software. The authentication of H. gordonii was achieved by comparing the band colors and Rf values for TLC fingerprints with those of 11 standard compounds including P57. The developed method was successfully applied for the identification of the 11 pregnane glycosides for four different species of Hoodia, 24 related genera and 13 dietary supplements that claim to contain H. gordonii. Different sample matrices were successfully analyzed, providing a wide range of applicability for this method, including gels, capsules, tablets, sprays, teas, snack bars, powders, and juices. The developed method was validated for specificity, stability, repeatability, and robustness. The results of HPTLC method were verified by LC‐UV‐MS method.
‘It's magic stuff’: The experiences of patients with ankylosing spondylitis taking anti‐TNF‐α medication
Authors: Stockdale J. , Goodacre L. 
Published: December 2008

AbstractIntroduction: Several studies have identified the efficacy of anti‐tumour necrosis factor‐alpha (anti‐TNF‐α) treatment in ankylosing spondylitis (AS). However, few studies have explored the perceptions of patients taking this new medication. The aim of this study was to explore the impact of anti‐TNF‐α on the quality of life of people with AS.Methods: A qualitative approach was adopted to provide a holistic understanding of participants' views and experiences in the context of their overall lives. Semi‐structured interviews were undertaken and transcribed verbatim. Data were analysed using thematic analysis. Ethical approval and informed consent were obtained.Results: Eight people participated and described a significant improvement in their physical and psychological status, leading to a more positive outlook on their life. Specific areas highlighted were employment, activities of daily living, hobbies and relationships with partners and family, some of which are not captured by current AS‐specific outcome measures. Negative aspects of anti‐TNF‐α use were described as the inconvenience of monitoring and issues relating to travelling abroad. All participants expressed concern about the possibility of being withdrawn from treatment and the perceived impact this would have on their lives.Conclusions: Anti‐TNF‐α treatment has a positive impact on the lives of people with AS, such that a major concern is being withdrawn from treatment, highlighting the need to provide tailored support to people being withdrawn from treatment. To capture the full impact of anti‐TNF‐α treatment, further consideration needs to be given to the choice of appropriate outcome measures. Copyright © 2008 John Wiley & Sons, Ltd.
The importance of defining periods of complete mortality reporting for research using automated data from primary care
Authors: Maguire Andrew , Blak Betina T. , Thompson Mary 
Published: December 2008

AbstractPurposeTo define periods of acceptable mortality reporting in primary care and to demonstrate through examples the implication for research using automated medical data.MethodsAnnual death counts were obtained for each primary care practice participating in The Health Improvement Network “THIN” (UK). Expected counts were calculated from national death rates, accounting for the practice's age/sex structure. The standardized mortality ratio (SMR) was calculated with 95% confidence intervals (CI). A visual review process was undertaken to assign the year from which the practice had acceptable mortality reporting (AMR). The process involved reviewer pairs who were blinded to each other's decisions. Patterns of death reporting were checked. The AMR year was applied as a filter to THIN data to assess its impact on the SMR.ResultsFor most practices the SMR was relatively stable and the AMR year was easily identified with 86% agreement between the blinded reviewer pairs. Applying the AMR to THIN removed under‐reporting of death. However, the total computerized follow‐up reduced from 37 to 32 million patient‐years. Problematic death recording patterns included some practices keeping only live patient records when converting their software systems thereby creating ‘immortal periods’ prior to this moment, and peaks occurring when practices updated the vital status of their patients' records.ConclusionsThis is the first time that an external standard has been used to assess completeness of mortality in automated primary care data. The resulting AMR year provides a natural filter for research and avoids biases associated with ‘immortal periods’, record updating and under‐reporting. Copyright © 2008 John Wiley & Sons, Ltd.
A Dunnett–Bonferroni‐based parallel gatekeeping procedure for dose–response clinical trials with multiple endpoints
Authors: Xu Haiyan , Nuamah Isaac , Liu Jingyi , Lim Pilar , Sampson Allan 
Published: December 2008

AbstractThis paper proposes a Dunnett–Bonferroni‐based parallel gatekeeping procedure in a setting of dose–response clinical trials with multiple endpoints. It follows the Dunnett‐based parallel gatekeeping strategy of Dmitrienko et al. (Pharm. Stat. 2006; 5:19–28), but differs in the calculation of the critical values. The implementation of the Dunnett‐based parallel gatekeeping procedure relies on assumptions difficult to justify in typical clinical trials, namely (a) that the joint distribution of the test statistics from different endpoints can be approximated by a multivariate‐t distribution and (b) that the true correlation between multiple endpoints can be well estimated using observed data. The proposed Dunnett–Bonferroni‐based parallel gatekeeping procedure relaxes the preceding assumptions by splitting type I error rate among families using the Bonferroni inequality. While it is potentially less powerful than a Dunnett‐based procedure when both procedures are applicable, the power loss is very minimal. Our proposed method avoids assumptions that might be challenged by regulatory agencies and does so with virtually no cost. Moreover, in most cases this method is easier to implement compared with the Dunnett‐based procedure. Copyright © 2008 John Wiley & Sons, Ltd.
T‐Jump/time‐of‐flight mass spectrometry for time‐resolved analysis of energetic materials
Authors: Zhou Lei , Piekiel Nicholas , Chowdhury Snehaunshu , Zachariah Michael R. 
Published: December 2008

AbstractWe describe a new T‐Jump/time‐of‐flight (TOF) mass spectrometer for the time‐resolved analysis of rapid pyrolysis chemistry of solids and liquids, with a focus on energetic materials. The instrument employs a thin wire substrate which can be coated with the material of interest, and can be rapidly heated (105 K/s). The T‐Jump probe is inserted within the extraction region of a linear TOF mass spectrometer, which enables multiple spectra to be obtained during a single reaction event. By monitoring the electrical characteristics of the heated wire, the temperature could also be obtained and correlated to the mass spectra. As examples, we present time‐resolved spectra for the ignition of nitrocellulose and RDX. The fidelity of the instrument is demonstrated in the spectra presented which show the temporal formation and decay of several species in both systems. The simultaneous measurement of temperature enables us to extract the ignition temperature and the characteristic reaction time. The time‐resolved mass spectra obtained show that these solid energetic material reactions, under a rapid heating rate, can occur on a time scale of milliseconds or less. While the data sampling rate of 10 000 Hz was used in the present experiments, the instrument is capable of a maximum scanning rate of up to ∼30 kHz. The capability of high‐speed time‐resolved measurements offers an additional analytical tool for the characterization of the decomposition, ignition, and combustion of energetic materials. Copyright © 2008 John Wiley & Sons, Ltd.
High‐speed separation and characterization of major constituents in Radix Paeoniae Rubra by fast high‐performance liquid chromatography coupled with diode‐array detection and time‐of‐flight mass spectrometry
Authors: Liu E‐Hu , Qi Lian‐Wen , Li Bin , Peng Yong‐Bo , Li Ping , Li Chang‐Yin , Cao Jun 
Published: December 2008

AbstractA fast high‐performance liquid chromatography (HPLC) method coupled with diode‐array detection (DAD) and electrospray ionization time‐of‐flight mass spectrometry (ESI‐TOFMS) has been developed for rapid separation and sensitive identification of major constituents in Radix Paeoniae Rubra (RPR). The total analysis time on a short column packed with 1.8‐µm porous particles was about 20 min without a loss in resolution, six times faster than the performance of a conventional column analysis (115 min). The MS fragmentation behavior and structural characterization of major compounds in RPR were investigated here for the first time. The targets were rapidly screened from RPR matrix using a narrow mass window of 0.01 Da to restructure extracted ion chromatograms. Accurate mass measurements (less than 5 ppm error) for both the deprotonated molecule and characteristic fragment ions represent reliable identification criteria for these compounds in complex matrices with similar if not even better performance compared with tandem mass spectrometry. A total of 26 components were screened and identified in RPR including 11 monoterpene glycosides, 11 galloyl glucoses and 4 other phenolic compounds. From the point of time savings, resolving power, accurate mass measurement capability and full spectral sensitivity, the established fast HPLC/DAD/TOFMS method turns out to be a highly useful technique to identify constituents in complex herbal medicines. Copyright © 2008 John Wiley & Sons, Ltd.
Characterization of glycopeptides by combining collision‐induced dissociation and electron‐transfer dissociation mass spectrometry data
Authors: Alley William R. , Mechref Yehia , Novotny Milos V. 
Published: December 2008

AbstractStructural characterization of a glycopeptide is not easily attained through collision‐induced dissociation (CID), due to the extensive fragmentation of glycan moieties and minimal fragmentation of peptide backbones. In this study, we have exploited the potential of electron‐transfer dissociation (ETD) as a complementary approach for peptide fragmentation. Model glycoproteins, including ribonuclease B, fetuin, horseradish peroxidase, and haptoglobin, were used here. In ETD, radical anions transfer an electron to the peptide backbone and induce cleavage of the N–Cα bond. The glycan moiety is retained on the peptide backbone, being largely unaffected by the ETD process. Accordingly, ETD allows not only the identification of the amino acid sequence of a glycopeptide, but also the unambiguous assignment of its glycosylation site. When data acquired from both fragmentation techniques are combined, it is possible to characterize comprehensively the entire glycopeptide. This is being achieved with a mass spectrometer capable of alternating between CID and ETD on‐the‐fly during an LC/MS/MS analysis. This is demonstrated here with several tryptic glycopeptides. Copyright © 2008 John Wiley & Sons, Ltd.
The tribological behaviours of dithiocarbamate‐triazine derivatives as additives in mineral oil
Authors: Wu Hua , Li Jing , Ma Haibing , Ren Tianhui 
Published: December 2008

AbstractAshless and non‐phosphorus hydroxyl‐containing dithiocarbamate‐triazine compounds,2,4,6‐tri[N,N‐di‐i‐octyldithiocarmate‐(2′‐hydroxyl)‐propionylthio]‐1,3,5‐s‐triazine (LDION) were prepared and their tribological behaviour as additives in mineral oil were evaluated using a four‐ball tester. Thermal degradation tests were conducted to identify their thermal stabilities using a thermo‐gravimetric analyser. The worn surfaces were investigated by X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption near edge structure (XANES) spectroscopy. The results indicate that the additive LDION possesses high thermal stabilities and good load‐carrying capacities. Moreover, it has good anti‐wear property at all test concentration and under all test loads. The results of XPS and XANES analyses illustrate that the prepared compounds as additives in mineral oil forms a protective film containing oxidised compounds and organic nitrogen‐containing compounds and inorganic sulfate on the metal surface during sliding process. Copyright © 2008 John Wiley & Sons, Ltd.
Aging behavior of PBO fibers and PBO‐fiber‐reinforced PPESK composite after oxygen plasma treatment
Authors: Zhang Chengshuang , Chen Ping , Liu Dong , Wang Baichen , Li Wei , Kang Xiaotao 
Published: December 2008

AbstractAging behavior of poly(p‐phenylene benzobisoxazole) (PBO) fibers and PBO‐fiber‐reinforced poly(phthalazinone ether sulfone ketone) (PPESK) composites after oxygen plasma treatment was investigated. Surface chemical composition, surface roughness and surface morphologies of oxygen‐plasma‐treated PBO fibers before and after aging in air for 1, 3, 5 and 10 days were analyzed by XPS and atomic force microscopy (AFM). The effects of aging on the material were examined by interlaminar shear strength (ILSS) and water absorption measurements. The results indicate that the major aging behavior of the fibers and the composite appeared in the first few days after oxygen plasma treatment, whereas minor aging effects were observed with prolonged aging. Copyright © 2008 John Wiley & Sons, Ltd.
Working‐correlation‐structure identification in generalized estimating equations
Authors: Hin Lin‐Yee , Wang You‐Gan 
Published: December 2008

AbstractSelecting an appropriate working correlation structure is pertinent to clustered data analysis using generalized estimating equations (GEE) because an inappropriate choice will lead to inefficient parameter estimation. We investigate the well‐known criterion of QIC for selecting a working correlation structure, and have found that performance of the QIC is deteriorated by a term that is theoretically independent of the correlation structures but has to be estimated with an error. This leads us to propose a correlation information criterion (CIC) that substantially improves the QIC performance. Extensive simulation studies indicate that the CIC has remarkable improvement in selecting the correct correlation structures. We also illustrate our findings using a data set from the Madras Longitudinal Schizophrenia Study. Copyright © 2008 John Wiley & Sons, Ltd.