bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of the stochastic resonance algorithm to the simultaneous quantitative determination of multiple weak peaks of ultra‐performance liquid chromatography coupled to time‐of‐flight mass spectrometry
Authors: Deng Haishan , Shang Erxin , Xiang Bingren , Xie Shaofei , Tang Yuping , Duan Jin‐ao , Zhan Ying , Chi Yumei , Tan Defei 
Published: February 2011

AbstractThe stochastic resonance algorithm (SRA) has been developed as a potential tool for amplifying and determining weak chromatographic peaks in recent years. However, the conventional SRA cannot be applied directly to ultra‐performance liquid chromatography/time‐of‐flight mass spectrometry (UPLC/TOFMS). The obstacle lies in the fact that the narrow peaks generated by UPLC contain high‐frequency components which fall beyond the restrictions of the theory of stochastic resonance. Although there already exists an algorithm that allows a high‐frequency weak signal to be detected, the sampling frequency of TOFMS is not fast enough to meet the requirement of the algorithm. Another problem is the depression of the weak peak of the compound with low concentration or weak detection response, which prevents the simultaneous determination of multi‐component UPLC/TOFMS peaks. In order to lower the frequencies of the peaks, an interpolation and re‐scaling frequency stochastic resonance (IRSR) is proposed, which re‐scales the peak frequencies via linear interpolating sample points numerically. The re‐scaled UPLC/TOFMS peaks could then be amplified significantly. By introducing an external energy field upon the UPLC/TOFMS signals, the method of energy gain was developed to simultaneously amplify and determine weak peaks from multi‐components. Subsequently, a multi‐component stochastic resonance algorithm was constructed for the simultaneous quantitative determination of multiple weak UPLC/TOFMS peaks based on the two methods. The optimization of parameters was discussed in detail with simulated data sets, and the applicability of the algorithm was evaluated by quantitative analysis of three alkaloids in human plasma using UPLC/TOFMS. The new algorithm behaved well in the improvement of signal‐to‐noise (S/N) compared to several normally used peak enhancement methods, including the Savitzky‐Golay filter, Whittaker‐Eilers smoother and matched filtration. Copyright © 2011 John Wiley & Sons, Ltd.
Chemical ionization by [NO]+ and subsequent collision‐induced dissociation for the selective on‐line detection of monoterpenes and linalool
Authors: Rimetz‐Planchon Juliette , Dhooghe Frederik , Schoon Niels , Vanhaecke Frank , Amelynck Crist 
Published: February 2011

AbstractExisting on‐line Chemical Ionization Mass Spectrometry (CIMS) techniques for quantification of atmospheric trace gases, such as Biogenic Volatile Organic Compounds (BVOCs), suffer from difficulty in discriminating between isomeric (and more generally isobaric) compounds. Selective detection of these compounds, however, is important because they can affect atmospheric chemistry in different ways, depending on their chemical structure. In this work, Flowing Afterglow Tandem Mass Spectrometry (FATMS) was used to investigate the feasibility of the selective detection of a series of monoterpenes, an oxygenated monoterpene (linalool) and a sesquiterpene (β‐caryophyllene). Ions at m/z 137 from [H3O]+ chemical ionization of α‐pinene, linalool and β‐caryophyllene have been subjected to Collision‐Induced Dissociation (CID) with Ar in the collision cell of a tandem mass spectrometer at center‐of‐mass energies ranging between 0 and 8 eV. Similar fragmentation patterns were obtained, demonstrating that this method is not suited for the selective detection of these compounds. However, CID of the ions at m/z 136 produced via [NO]+ chemical ionization of a series of monoterpenes has revealed promising results. Some tracer‐product ions for individual compounds or groups of compounds were found, which can be considered as a step forward towards selective on‐line monitoring of BVOCs with CIMS techniques. Copyright © 2011 John Wiley & Sons, Ltd.
Efficient cell culture systems for hepatitis E virus strains in feces and circulating blood
Authors: Okamoto Hiroaki 
Published: February 2011

AbstractAttempts have been made to propagate hepatitis E virus (HEV) in primary hepatocyte culture and various other cultured cells. However, the replication ability of HEV recovered from culture media remains extremely low. Recently, efficient culture systems have been established in PLC/PRF/5 (hepatocellular carcinoma) and A549 (lung cancer) cell lines for HEV strains of genotypes 3 and 4 in our laboratory. They originated in fecal extracts from patients containing HEV RNA in extremely high‐titers (107 copies/ml), and named the JE03‐1760F (genotype 3) and HE‐JF5/15F (genotype 4) strains, respectively. HEV RNA in culture supernatants reached 108 copies/ml in titer, and were transmitted successively through many passages. An infectious HEV cDNA clone (pJE03‐1760F/wt) was constructed that has replication activity comparable to that of the wild‐type JE03‐1760F in feces. The ORF3 protein is indispensable for shedding HEV particles from cells in the reverse genetics system. HEV recovered from culture media, as well as circulating HEV, possess ORF3 proteins on the surface and are covered with cellular membranes, and therefore, ORF2 epitopes are buried in these particles. In contrast, HEV excreted into feces are naked nucleocapsids without a lipid layer or surface expression of the ORF3 protein. HEV in sera of patients with acute hepatitis E can infect and replicate in PLC/PRF/5 and A549 cells, with efficiency comparable to the circulating HEV RNA levels. High‐efficiency cell culture systems for infectious viruses, thus developed, are expected to open up a new era and resolve many mysteries in the epidemiology, molecular biology, and treatment of HEV. Copyright © 2011 John Wiley & Sons, Ltd.
THE RELATIONSHIP BETWEEN FINE SEDIMENT AND MACROPHYTES IN RIVERS
Authors: Jones J.I. , Collins A.L. , Naden P.S. , Sear D.A. 
Published: February 2011

ABSTRACTThe interplay between erosion and deposition are fundamental characteristics of river basins. These processes result in the delivery, retention and conveyance of sediment through river systems. Although the delivery of sediment to rivers is a natural phenomenon, in recent years there has been increasing concern about the enhancement of sediment loadings as a result of anthropogenic activities. The presence of macrophytes in river channels tends to increase the retention of fine sediment leading to changes in bed composition. However, a complex relationship exists between macrophytes and fine sediment: macrophytes affect the conveyance of fine sediment and are, in turn, affected by the sediment loading. This review deals with these two reciprocal effects and, in particular, summarizes the available evidence base on the impact of fine sediment on macrophytes. Increased inputs of fine sediment appear to have both direct and indirect impacts on the macrophyte community, altering light availability, and the structure and quality of the river bed. The nature of these impacts depends largely on the rate of deposition and the nature of the material deposited. Changes in macrophyte community composition may ensue where the depositing material is more nutrient rich than the natural river bed. Many of the changes in macrophyte flora that occur with increased fine sediment inputs are likely to closely parallel those that occur with increased dissolved nutrient availability. If attempts to manage nutrient inputs to rivers are to achieve their goals, it is critical that fine sediment‐associated nutrient dynamics and transfers are considered. Copyright © 2011 John Wiley & Sons, Ltd.
SEDIMENT TRANSPORT AND FLOW DYNAMICS AROUND A RESTORED POOL IN A FISH HABITAT REHABILITATION PROJECT: FIELD AND 3D NUMERICAL MODELLING EXPERIMENTS
Authors: Biron P. M. , Carver R. B. , Carré D. M. 
Published: February 2011

ABSTRACTFew studies have examined sediment transport patterns around in‐stream structures used to enhance fish habitat despite the importance of this variable in the successful design of stream restoration schemes. The objective of this study is to examine interactions between the (excavated) pool morphology, flow and sediment transport in a restored reach of the Nicolet River (Quebec, Canada). Bedload transport was investigated using passive integrated transponder (PIT) tagged particles that were followed from positions upstream of a pair of current deflectors which were designed to maintain the excavated pool downstream. Three‐dimensional numerical simulations of the flow field at various flow stages (with emerged or submerged deflectors) were used to relate near‐bed velocity and bed shear stress to transport patterns and to assess the impact of varying the pool location and geometry on the flow field and water surface profiles. Results show that from 2005 to 2008, of the 117 pit‐tagged particles that fell in the pool, only 27 are known to have exited. None of the 30 largest rocks entering the pool escaped. Bed shear stress values simulated at high and peak flow (slightly above bankfull level) are not sufficient to move the largest rocks in the pool exit zone. Simulations also reveal a complex water surface topography when flow is above the height of deflectors, with negative water surface slope in the pool zone. When modifying the pool geometry so that the deepest zones are close to the apex of the in‐stream structures instead of in the centre of the channel, both water surface slope and near‐bed velocity patterns are greatly modified. Understanding the interactions between excavated pools, bedload and 3D velocity patterns around in‐stream structures is essential for long‐term success of fish habitat restoration projects, and using 3D models to test various designs of artificial pools is a promising approach. Copyright © 2011 John Wiley & Sons, Ltd.
PBTE as a research vehicle: A way out of the forest
Authors: Bruce Matthew H. , Bernard Miller H. 
Published: February 2011

AbstractThe move into Performance‐Based Teacher Education has been precipitous. Rather than a one‐shot move into what passes for a full PBTE format, a gradual phasing‐in operation concurrent with suitable research seems desirable. Without the research information, PBTE may become another bandwagon passing across the educational scene without making any discernible change in teacher education.Some consistent view of the overall educational enterprise and of the teaching act, relating these to PBTE, is an absolute necessity. The PBTE move provides a useful research vehicle regardless of any verdict reached on its efficacy as a teacher education format.Current funding of educational research on a scale appropriate to the kinds of questions needing study appears limited. This suggests that a viable approach to researching both those vital questions connecting what teachers do and acceptable goals for pupils and PBTE as a vehicle must employ existing program components such as microteaching. This also suggests similar research designs be employed in many places if the summation of results is to provide useful information.
A formal separation method of protocols to eliminate parallel attacks in virtual organization
Authors: Zhao Hui , Li Mingchu , Fan Xinxin 
Published: February 2011

AbstractThe purpose of this paper is to introduce a technique to eliminate parallel attacks to protocol in virtual organization (VO) through enforcing dynamic authorization policies. Grid realizes coordinated resource sharing across multiple management domains. VO is defined as a key concept for operation and management of grid services. Due to the fact that VO focuses on dynamic, cross‐organizational sharing relationships, one of the central challenges in the construction of scalable VO is that protocol specified by VO may have process of parallel running. To solve this problem, we present a formal definition of non‐honest participants' malicious coordination operations which are necessary for parallel attack counterexample in VO. Based on that, we present the two‐level dynamic authorization policy deploying scheme in VO for eliminating parallel attacks. Copyright © 2011 John Wiley & Sons, Ltd.
Bayesian hierarchical modeling for a non‐randomized, longitudinal fall prevention trial with spatially correlated observations
Authors: Murphy T. E. , Allore H. G. , Leo‐Summers L. , Carlin B. P. 
Published: February 2011

AbstractBecause randomization of participants is often not feasible in community‐based health interventions, non‐randomized designs are commonly employed. Non‐randomized designs may have experimental units that are spatial in nature, such as zip codes that are characterized by aggregate statistics from sources like the U.S. census and the Centers for Medicare and Medicaid Services. A perennial concern with non‐randomized designs is that even after careful balancing of influential covariates, bias may arise from unmeasured factors. In addition to facilitating the analysis of interventional designs based on spatial units, Bayesian hierarchical modeling can quantify unmeasured variability with spatially correlated residual terms. Graphical analysis of these spatial residuals demonstrates whether variability from unmeasured covariates is likely to bias the estimates of interventional effect.The Connecticut Collaboration for Fall Prevention is the first large‐scale longitudinal trial of a community‐wide healthcare intervention designed to prevent injurious falls in older adults. Over a two‐year evaluation phase, this trial demonstrated a rate of fall‐related utilization at hospitals and emergency departments by persons 70 years and older in the intervention area that was 11 per cent less than that of the usual care area, and a 9 per cent lower rate of utilization from serious injuries. We describe the Bayesian hierarchical analysis of this non‐randomized intervention with emphasis on its spatial and longitudinal characteristics. We also compare several models, using posterior predictive simulations and maps of spatial residuals. Copyright © 2011 John Wiley & Sons, Ltd.
Supramolecular Polymers: Rigid Dimers Formed through Strong Interdigitated H‐Bonds Yield Compact 1D Supramolecular Helical Polymers (Small 3/2011)
Authors: Ciesielski Artur , Stefankiewicz Artur R. , Hanke Felix , Persson Mats , Lehn Jean‐Marie , Samorì Paolo 
Published: February 2011

AbstractHierarchical self‐assembly of small abiotic molecular modules interacting through noncovalent forces is increasingly being used to generate functional structures and materials for electronic, catalytic, and biomedical applications. The greatest control over the geometry in H‐bond supramolecular architectures, especially in H‐bonded supramolecular polymers, can be achieved by using conformationally rigid molecular modules undergoing self‐assembly through strong H‐bonds. Their binding strength depends on the multiplicity of the H‐bonds, the nature of donor/acceptor pairs and their secondary attractive/repulsive interactions. Here a functionalized molecular module is described, which is capable of self‐associating through self‐complementary H‐bonding patterns comprising four strong and two medium‐strength H‐bonds to form dimers. The self‐association of these phenylpyrimidine‐based dimers through directional H‐bonding between two lateral pyridin‐2(1H)‐one units of neighboring molecules allows the formation of highly compact 1D supramolecular polymers by self‐assembly on graphite. A concentration‐dependent study by scanning tunneling microscopy at the solid–liquid interface, corroborated by dispersion‐corrected density functional studies, reveals the controlled generation of either linear supramolecular 2D arrays, or long helical supramolecular polymers with a high shape persistence.
Assigning change requests to software developers
Authors: Kagdi Huzefa , Gethers Malcom , Poshyvanyk Denys , Hammad Maen 
Published: February 2011

SUMMARYThe paper presents an approach to recommend a ranked list of expert developers to assist in the implementation of software change requests (e.g., bug reports and feature requests). An Information Retrieval (IR)‐based concept location technique is first used to locate source code entities, e.g., files and classes, relevant to a given textual description of a change request. The previous commits from version control repositories of these entities are then mined for expert developers. The role of the IR method in selectively reducing the mining space is different from previous approaches that textually index past change requests and/or commits. The approach is evaluated on change requests from three open‐source systems:ArgoUML,Eclipse, andKOffice, across a range of accuracy criteria. The results show that the overall accuracies of the correctly recommended developers are between 47 and 96% for bug reports, and between 43 and 60% for feature requests. Moreover, comparison results with two other recommendation alternatives show that the presented approach outperforms them with a substantial margin. Project leads or developers can use this approach in maintenance tasks immediately after the receipt of a change request in a free‐form text. Copyright © 2011 John Wiley & Sons, Ltd.
Beyond words: Visual metaphors that can demonstrate comprehension of KM as a paradoxical activity system
Authors: McKenzie Jane , van Winkelen Christine 
Published: February 2011

AbstractFollowing criticism that, in business and management, metaphor is largely verbal and primarily used to convey similarity, this paper explores how visual metaphors can communicate the anomalous and the paradoxical aspects of KM more concisely than words, whilst simultaneously presenting more tacit associations to stimulate creative thinking. It considers a series of 30 assessed posters that aimed to re‐present six basic KM paradoxes through imagery that captures both the analogous and the anomalous. We found six categories of radial metaphors able to convey paradoxical complexity in a concise way. This has implications for organizations thinking about how to engage people with both the familiar and the strange. Copyright © 2011 John Wiley & Sons, Ltd.
Functional, digestibility, and antioxidant properties of brown and polished rice flour from traditional and new‐improved varieties grown in Sri Lanka
Authors: Gunaratne Anil , Bentota Amitha , Cai Yi Zhong , Collado Lilia , Corke Harold 
Published: February 2011

AbstractSri Lankan traditional and improved rice varieties were processed into brown and polished rice flours. Samples were analyzed for AM, protein, lipid, total phenolic content, and antioxidant activity. Gelatinization and retrogradation properties were observed in the Rapid Visco Analyzer (RVA) and DSC. The AM content of the samples was high to intermediate (20 to 26%) except for one which was low (17%). Brown rice flour (BRF) samples had lower swelling power, lower RVA viscoamylograph profile, lower gel hardness, lower gelatinization enthalpy but higher gelatinization peak temperature and lower melting enthalpies of its retrograded AP relative to its corresponding polished rice flour (PRF) samples. The BRF showed a lower decrease in peak viscosity in the RVA viscoamylograph as compared to its PRF when treated with α‐amylase indicating inhibition potential. The traditional rice varieties had 68 to 86% higher total phenolic content (TPC) and 86 to 90% antioxidant activity in the BRF samples as compared to the improved varieties. A study on the antioxidant profile of the brown rice of the traditional rice varieties is being undertaken to explore their value as functional foods.
Structural and physicochemical characterization of RS prepared using hydrolysis and heat treatments of chickpea starch
Authors: Polesi Luís Fernando , Sarmento Silene Bruder Silveira 
Published: February 2011

AbstractThe aim of this study was to evaluate the production and the structural and physicochemical properties of RS obtained by molecular mass reduction (enzyme or acid) and hydrothermal treatment of chickpea starch. Native and gelatinized starch were submitted to acid (2 M HCl for 2.5 h) or enzymatic hydrolysis (pullulanase, 40 U/g per 10 h), autoclaved (121°C/30 min), stored under refrigeration (4°C/24 h), and lyophilized. The hydrolysis of starch increased the RS content from 16% to values between 20 and 32%, and the enzymatic treatment of the gelatinized starch was the most efficient. RS showed an increase in water absorption and water solubility indexes due to hydrolytic and thermal process. The processes for obtaining RS changed the crystallinity pattern from C to B. Hydrolysis treatments caused an increase in relative crystallinity due to the greater retrogradation caused by the reduction in MW. RS obtained from hydrolysis showed a reduction in viscosity, indicating the rupture of molecules. The viscosity seemed to be inversely proportional to the RS content in the sample.
Physico–chemical, morphological, and pasting properties of Pine nut (Araucaria angustifolia) starch oxidized with different levels of sodium hypochlorite
Authors: Costa de Conto Leilane , Plata‐Oviedo Manuel Salvador Vicente , Joy Steel Caroline , Chang Yoon Kil 
Published: February 2011

AbstractThe objective of this work was to study the effect of process temperature and active chlorine concentration on the main properties of Pine nut starch (PN). Samples of PN were oxidized with sodium hypochlorite at concentrations varying from 0.5 to 4.0 g active chlorine/100 g starch, at temperatures varying from 20 to 45°C according to a central composite rotational design, analyzing the results using response surface methodology. The concentration of active chlorine had an effect on the WSI, the quantity of carboxyl and carbonyl groups, the AM content and the percentage of light transmittance (650 nm) of the PN. The effect of temperature was observed on the water solubility index, the quantity of carbonyl groups and the percentage of light transmittance (650 nm) of the PN. Oxidation was more intense in the starch treated with 3.5% active chlorine.
Characterizing starch structure in a gluten‐free pasta by using iodine vapor as a tool
Authors: Marti Alessandra , Pagani Maria Ambrogina , Seetharaman Koushik 
Published: February 2011

AbstractThe suitability of starch–iodine complex to highlight differences in chain mobility and crystallinity of starch in rice pasta was investigated. Two pasta samples were produced starting from the same rice flour (RF) and using a conventional extrusion process without (Process A) and with (Process B) a preliminary extrusion‐cooking step. Based on the absorption/scattering coefficient (K/S) spectra (obtained after equilibration above K2SO4 and exposure to iodine vapor), Pasta A showed a behavior similar to RF. Process B exhibited a greater iodine binding capacity suggesting greater starch chain mobility. Moreover, the extrusion‐cooking conditions seem to favor the loss of starch crystallinity and the formation of larger amorphous regions. The organization of starch polymers observed in Pasta B could account for its higher capacity to water absorption during cooking.