bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallographic Site Distribution and Redox Activity of Fe in Nontronites Determined by Optical Spectroscopy
Authors: Merola Rose B. , McGuire Molly M. 
Published: January 2010

AbstractOptical absorption spectroscopy has the potential to uncover many characteristics of Fe-bearing, redox-active smectites that have heretofore been hidden. The purpose of this study was to exploit this technique to reveal the temperature dependence of the spectra and to characterize the behavior of octahedral and tetrahedral Fe(III) under various stages of reduction. The Uley nontronites, NAu-1 and NAu-2, were compared using optical spectroscopy, which probed the crystallographic-site distribution of Fe in the clay structures as well as the resulting differences in the reduction process in the two minerals. All of the major differences in the spectra of the two minerals in the wavelength range 450–950 nm are due to the presence of a significant amount of tetrahedral Fe(III) in NAu-2.In situobservation of the optical spectra of NAu-1 suspensions as a function of the degree of reduction reveals a steady increase in the dominant intervalence charge transfer (IVCT) band and the resulting blue-green color as the Fe(II) content of the octahedral sheet increases. Although the spectrum of NAu-2 at ∼50% reduction looks nearly identical to the spectrum of NAu-1 at a similar state of reduction, the spectra corresponding to the initial stages of reduction are quite different. Stepwise reduction of NAu-2 causes a rapid decrease in the absorbance features due to crystal-field transitions of tetrahedral Fe(III) before the IVCT band appears, suggesting that tetrahedral Fe(III) is preferentially reduced before the octahedral Fe(III). The intensity of the absorbance features due to tetrahedral Fe(III) also exhibit an inverse temperature dependence, suggesting that they are enhanced due to exchange-coupling with Fe(III) ions in neighboring sites. Spectra of NAu-1 at liquid nitrogen temperature, therefore, allowed the identification of a small amount of tetrahedral Fe(III) in NAu-1 that had not been noted previously.
Realizing the cognitive potential of children 5–7 with a mathematics focus: Post‐test and long‐term effects of a 2‐year intervention
Authors: Shayer Michael. , Adhami Mundher. 
Published: January 2010

BackgroundIn the context of the British Government's policy directed on improving standards in schools, this paper presents research on the effects of a programme intended to promote the cognitive development of children in the first 2 years of primary school (Y1 & 2, aged 5–7 years). The programme is based on earlier work dealing with classroom‐based interventions with older children at both primary and secondary levels of schooling.AimThe hypothesis tested is that it is possible to increase the cognitive ability of children by assisting teachers towards that aim in the context of mathematics. A corollary hypothesis is that such an increase would result in an increase in long‐term school achievement.SampleThe participants were 8 teachers in one local education authority (LEA) and 10 teachers in another. Data were analysed on 275 children present at Year 1 pre‐test in 2002 and at long‐term Key Stage 2 post‐test in 2008.MethodTwo intervention methods were employed: a Y1 set of interactive activities designed around Piagetian concrete operational schemata, and mathematics lessons in both Y1 and Y2 designed from a theory‐base derived from both Piaget and Vygotsky.ResultsAt post‐test in 2004, the mean effect sizes for cognitive development of the children – assessed by the Piagetian test Spatial Relations – were 0.71 SD in one LEA and 0.60 SD in the other. Five classes achieved a median increase of 1.3 SD. The mean gains over pre‐test in 2002 for all children in Key Stage 1 English in 2004 were 0.51 SD, and at Key Stage 2 English in 2008 – the long‐term effect – were 0.36 SD, an improvement of 14 percentile points.ConclusionsThe main hypothesis was supported by the data on cognitive development. The corollary hypothesis is supported by the gains in English. The implications of this study are that relative intelligence can be increased and is not fixed, and that children can be led into collaborating with each other to the benefit of their own thinking, and that there does exist a theory‐based methodology for the improvement of teaching.
Evaluating the effectiveness of a road safety education intervention for pre‐drivers: An application of the theory of planned behaviour
Authors: Poulter Damian R. , McKenna Frank P. 
Published: January 2010

BackgroundYoung drivers are overrepresented in road traffic fatalities and collisions. Attempts to address this problem with pre‐driver education have not met with unambiguous success. However, there is a lack of research on whether pre‐driver education can change psychological antecedents to behaviour.AimsThe framework of the theory of planned behaviour (TPB) was employed to assess the effectiveness of an educational intervention used across the UK that aims to improve attitudes to road safety in pre‐drivers.Sample(s)Secondary school students aged 15–16 years participated in the research, drawn from 12 schools in the UK. A total of 199 students took part in Expt 1 and 430 in Expt 2.MethodExpt 1 employed a within‐participants design to measure any changes in road safety beliefs from pre‐ to post‐intervention and 5‐month follow‐up. Expt 2 used a between‐participants design to test whether any changes were genuine or due to experimenter effects.ResultsResults of Expt 1 revealed a small, short‐term improvement in some pre‐driver beliefs immediately following the educational intervention, but no effect on other beliefs, and some evidence of unintended outcomes. The small, significant improvements found in Expt 1 were replicated in Expt 2, which is consistent with there being a genuine effect.ConclusionsConsidering evidence from both experiments suggests the effectiveness of road safety education interventions are at best short term, and limited to some but not all psychological factors, with some risk of unintended consequences.
Newborn Screening for Galactosemia: A Review of 5 Years of Data and Audit of a Revised Reporting Approach
Authors: Freer Dennis E , Ficicioglu Can , Finegold David 
Published: January 2010

Abstract
Background: Availability of the galactose-1-phosphate uridyltransferase (GALT) assay for newborn (NB) screening has improved identification of classic galactosemia. Previously defined critical cutoffs for total galactose (Gal), typically 1.110 mmol/L (20 mg/dL), are still in use in laboratories measuring total Gal for the diagnosis of nonclassic galactosemias. Urgent notification/referral to a treatment center follows, although few of the NBs will need treatment.
Methods: We reviewed all NB galactosemia-screening results and their corresponding clinical outcomes over a 5-year period (first phase, 1.32 × 106 NBs) and then over a 2-year period (second phase, 274 960 NBs). Each NB was screened for Gal and GALT. When Gal was increased and/or GALT was deficient, testing for percentage galactose-1-phosphate and/or DNA testing for common GALT mutations were performed.
Results: Of 209 reported positive results, 89% did not indicate GALT deficiency. These non–GALT-deficient results represented mostly clinically benign cases with a Gal threshold of ≥1.110 mmol/L (≥20 mg/dL). The positive predictive value of a GALT cutoff of ≤40 μmol/L was 83%. After a protocol change that redefined a critical result as a GALT value ≤40 μmol/L and/or a Gal value ≥1.665 mmol/L (≥30 mg/dL), results were monitored for an additional 2 years. The new protocol dramatically reduced the number of urgent calls/referrals and reduced the total number of referrals by nearly half.
Conclusions: Use of a GALT cutoff of ≤40 μmol/L/L and a Gal cutoff of ≥1.665 mmol/L (≥30 mg/dL) for urgent notification/referral dramatically reduces false positives and unnecessary follow-up, thereby reducing the stress on healthcare resources.
Recombinant manganese peroxidase (rMnP) from Pichia pastoris. Part 1: Kraft pulp delignification
Authors: Xu Haowen , Scott Gary M. , Jiang Fei , Kelly Christine 
Published: January 2010

AbstractManganese peroxidase (MnP) is the main enzyme implicated in the biobleaching of kraft pulps by white-rot fungi. However, potential commercial applications of this enzyme have been limited by its availability in large quantities. Advances have been made to produce high-yield concentrated recombinant MnP (rMnP). The objective of this study was to evaluate the ability of rMnP to delignify and brighten kraft pulps. The rMnP, produced from the yeastPichia pastoris– in high-cell density and in fed-batch fermentations – was found to be effective in lignin removal in both hardwood and softwood unbleached kraft pulps. The rMnP applied at 30 U g-1pulp for 24 h followed by alkali extraction caused significant kappa number reductions for all the pulps tested with different initial lignin contents and structures. Softwood and hardwood pulps showed similar delignification rates during rMnP treatments. Highly delignified pulps with kappa number less than 10 are less susceptible to delignification by rMnP compared with the pulps with higher lignin content. The rMnP-treated pulp was also shown to be more susceptible to subsequent peroxide bleaching compared with the control pulp. More than 60% of the kappa number reduction was achieved by sequential rMnP treatments combined with alkaline extraction. Sequential treatment with xylanase and rMnP also resulted in more extensive delignification than in each enzyme treatment alone or in the case of simultaneous application of the enzymes.
The role of hydroxyl and oxyl anion radicals in selectivity of oxygen delignification
Authors: Bouchard Jean , Wang Jie , Berry Richard 
Published: January 2010

Abstract
The concentration of the hydroxyl radical generated during oxygen delignification was measured with a radical trapping agent. The N,N′-(5-nitro-1,3-phenylene)-bisglutaramide (NPG) was found to be effective but the experiments revealed that at pH higher than 11.5 the anionic form of hydroxyl radical – the oxyl anion radical – causes up to four times more chain cleavage than the hydroxyl radical. It was also found that the effect of both radicals in the pulp moderated at higher partial oxygen pressure and in the presence of hemicelluloses. The implications are that selectivity can be improved by maintaining a moderate alkaline pH profile, increasing the oxygen partial pressure, and retaining hemicelluloses in the brownstock.
Fractionation, analysis, and PCA modeling of properties of four technical lignins for prediction of their application potential in binders
Authors: Gosselink Richard J.A. , van Dam Jan E.G. , de Jong Ed , Scott Elinor L. , Sanders Johan P.M. , Li Jiebing , Gellerstedt Göran 
Published: January 2010

Abstract
Functional properties of technical lignins need to be characterized in more detail to become a higher added value renewable raw material for the chemical industry. The suitability of a lignin from different plants or trees obtained by different technical processes can only be predicted for selected applications, such as binders, if reliable analytical data are available. In the present paper, structure dependent properties of four industrial lignins were analyzed before and after successive organic solvent extractions. The lignins have been fractionated according to their molar mass by these solvents extractions. Kraft and soda lignins were shown to have different molar mass distributions and chemical compositions. Lignin carbohydrate complexes are most recalcitrant for extraction with organic solvents. These poorly soluble complexes can consist of up to 34% of carbohydrates in soda lignins. Modeling by principle component analysis (PCA) was performed aiming at prediction of the application potential of different lignins for binder production. The lignins and their fractions could be classified in different clusters based on their properties, which are structure dependent. Kraft softwood lignins show the highest potential for plywood binder application followed by hardwood soda lignin and the fractions of Sarkanda grass soda lignin with medium molar mass. Expectedly, the softwood lignins contain the highest number of reactive sites in ortho positions to the phenolic OH group. Moreover, these lignins have a low level of impurities and medium molar mass.
Effect of helium DBD plasma treatment on the surface of wood samples
Authors: Asandulesa Mihai , Topala Ionut , Dumitrascu Nicoleta 
Published: January 2010

Abstract
The effects of helium dielectric barrier discharge (He-DBD) plasma treatment has been studied aiming at the preparation of wood for profitable dye covering and impregnation with an antibacterial oil. Electrical and optical emission spectroscopy measurements were performed to characterise the He-DBD discharge. The hydrophilic/hydrophobic properties of the modified surfaces were studied by dynamic contact angle measurements. The spreading area of the wet spots was also evaluated as a function of wetting time. After He-DBD plasma exposure, the adhesion properties are substantially improved and the hydrophilic character of wood surface is enhanced. The behaviour of linseed oil drops on the modified surfaces confirmed the utility of He-DBD treatment.
Reactivity of syringyl quinone methide intermediates in dehydrogenative polymerization. Part 2: pH effect in horseradish peroxidase-catalyzed polymerization of sinapyl alcohol
Authors: Tobimatsu Yuki , Takano Toshiyuki , Kamitakahara Hiroshi , Nakatsubo Fumiaki 
Published: January 2010

Abstract
The solvent pH effect in the horseradish peroxidase (HRP)-catalyzed polymerization of sinapyl alcohol (S-alc) and analogously, sinapyl alcohol γ-O-glucoside (isosyringin, iso-S) was investigated particularly focusing on the behavior of syringyl-type quinone methide intermediates (S-type QMs) under acidic conditions. At first, the HRP-catalyzed polymerization of iso-S at pH 6.5–2.5, which produces water-soluble dehydrogenation polymer (DHP) intermediates in a homogeneous phase, was monitored by UV spectroscopy and gel permeation chromatography with photodiode array detection (GPC-PDA). Under acidic conditions at pH below 4.5, unstablilized S-type QMs from iso-S are rapidly quenched resulting in efficient productions of DHPs, although substantial loss of HRP activity and the resulting insufficient polymerization were inevitable at pH below 3.5. In addition, it was found that a small addition of guaiacyl-type comonomer (isoconiferin, iso-G) effectively promotes the polymerization of iso-S under acidic conditions, in which the comonomer serves as a radical mediator to facilitate the HRP-catalyzed oxidations of iso-S. Next, the HRP-catalyzed polymerization of S-alc at various pH values was conducted and the resulting DHPs were characterized by GPC and NMR measurements. The yields of isolated DHPs significantly increased as solvent pH decreased below 4.5. The structural analyses of the DHPs demonstrated that reaction selectivity of S-type QMs during the polymerization drastically changed at pH below 4.5: they react efficiently with water molecules as solvent leading to the formation of benzyl alcohol type β-O-4 substructures preferentially to the formation of α-O-aryl type substructures. Consequently, the data in this study demonstrated that acidic conditions at pH below 4.5 are favored in the dehydrogenative polymerization of S-alc from the viewpoint of the reactivity of S-type QMs.
Surface properties of extracts from cork black condensate
Authors: Pires Ricardo A. , Mano João F. , Reis Rui L. 
Published: January 2010

Abstract
The insulation corkboard production generates black condensate (BC), a paste-like solid waste. It is hydrophobic and has the potential to be used as protective coating. To evaluate this potential, coatings were prepared from BC extracts and their surface behavior was evaluated by contact angle (CA) measurements. The CA dynamics were recorded as a function of time; advancing CAs were also registered; the approaches were applied according to Fowkes, Owens-Wendt-Rabel-Kaelble (OWRK), and Van Oss to determine the surface energy (SE) for each coating. Depending on the liquid probe, three phenomena were observed: water evaporation, diiodomethane diffusion into the coating, and rearrangement of the chemical groups on the coating surface, when glycerol was dropped onto the surface. Based on the results from the CA dynamics, the applicability of the coatings against hydrophobic environments was limited owing to its affinity to apolar compounds. The results show that the coating prepared by the toluene BC extract was the best coating. The key data were: water CA of 99.3°, total SE (between 37.4 mN m-1 and 40.1 mN m-1), SE polar component (0.1 mN m-1), and the acidic and basic characters were negligible. It can be concluded that the BC extracts have potential for coatings.
A study of water exchange in wood by means of 2D NMR relaxation correlation and exchange
Authors: Cox Julia , McDonald Peter J. , Gardiner Barry A. 
Published: January 2010

Abstract
Two-dimensional T
1-T
2
1H NMR relaxation correlation spectra and T
2-T
2 relaxation exchange spectra for samples of spruce wood across the full moisture content range from 0% to >100% are presented. The T
1-T
2 spectra unambiguously identify water in different environments within the wood that overlap in the corresponding and more traditional one-dimensional T
1 or T
2 experiment. The T
2-T
2 spectra unambiguously reveal the presence of water exchange between the lumen and cell wall above the fibre saturation point in sapwood. An estimate is made of the exchange rate: 1/30 to 1/3 ms-1.
A Weibull Stress Model to Predict Effects of Weld Strength Mismatch on Cleavage Fracture Toughness
Authors: Ruggieri Claudio 
Published: January 2010

Abstract
This work describes the development of a toughness scaling methodology incorporating the effects of weld strength mismatch on crack-tip driving forces. The approach adopts a nondimensional Weibull stress, σ¯w, as a the near-tip driving force to correlate cleavage fracture across cracked weld configurations with different mismatch conditions even though the loading parameter (measured by J or crack-tip opening displacement) may vary widely due to mismatch and constraint variations. Application of the procedure to predict the failure strain for an overmatch girth weld made of an API X80 pipeline steel demonstrates the effectiveness of the micromechanics approach. Overall, the results lend strong support to use a Weibull stress based procedure in defect assessments of structural welds.
Size Effects in Flexural Toughness of Fiber Reinforced Concrete
Authors: Jiang Zhengwu , Banthia Nemkumar 
Published: January 2010

Abstract
The influence of specimen size on measured flexural toughness of fiber reinforced concrete (FRC) remains largely unknown. Towards this end, an experimental program was carried out where flexural toughness tests were performed on specimens of two different sizes using ASTM C1609/C1609M-07 test procedure. Two specimen sizes of 100×100×350 mm3 and 150×150×500 mm3 were tested. A hybrid polymeric fiber at three fiber dosage rates of 3.0, 4.5, and 6.0 kg/m3 was investigated. Results indicate that the specimen size affects not only the toughness properties but also the variability in data as quantified by the coefficient of variation (COV). Size effect was more pronounced in the early part of the load-deflection curve and decreased with an increase in the fiber volume fraction. At a given fiber volume fraction, the COV, moduli of rupture, and post-crack residual strengths were all higher for the specimens of smaller size. Finally, the small size specimens showed a greater deflection hardening than the large size specimens. The last conclusion is significant in that deflection hardening is now often cited as the required performance characteristic of high performance FRC, and this property may depend more on the size of the specimens than on the composite itself.
Abnormal glucose tolerance in children with cystic fibrosis: the predictive role of continuous glucose monitoring system
Authors: Schiaffini Riccardo , Brufani Claudia , Russo Beatrice , Fintini Danilo , Migliaccio Antonella , Pecorelli Lia , Bizzarri Carla , Lucidi Vincenzina , Cappa Marco 
Published: January 2010

A long pre-diabetic phase of abnormal glucose tolerance is described in subjects with cystic fibrosis (CF) since childhood.ObjectiveThe aims of the study were to compare oral glucose tolerance test (OGTT) and continuous glucose monitoring system (CGMS) in the diagnosis of altered glucose metabolism, and to longitudinally evaluate the role of CGMS in predicting glucose metabolism deterioration in children with CF.MethodsSeventeen children with CF and 14 controls were enrolled (mean age 13.3±3.0 years). All subjects underwent OGTT and CGMS registration. On the basis of OGTT, children were classified as normal glucose tolerance, impaired glucose tolerance (IGT), IGT plus at least one glucose value above 200 mg/dl at intermediate OGTT points (IGT+200) and CF-related diabetes (CFRD). HbA1c, glucose area under the curve, insulin sensitivity, and insulinogenic and disposition indexes were also considered. Subjects with CF underwent another OGTT after 2.5 years.ResultsBaseline OGTT revealed 3/17 (7.6%) children with CF with at least one glucose value above 200 mg/dl (1 CFRD and 2 IGT+200), while CGMS revealed 6/17 (35.3%) children with glucose excursions above 200 mg/dl (P=0.010). None of the controls showed glucose over 200 mg/dl either at OGTT or at CGMS. At the 2.5-year follow-up OGTT, all the six subjects who had diabetic glucose excursion (i.e. >200 mg/dl) at baseline CGMS presented IGT+200 or CFRD. In logistic regression analysis, CGMS diabetic excursion was the strongest predictor of IGT+200 and CFRD (P<0.001).ConclusionsCGMS could be a useful tool to predict glucose metabolism derangements in children affected by CF.
Mechanical Fabrication of Si-Ge-B Bulk Samples with Superior Thermoelectric Power
Authors: Abe Makoto , Takiguchi Hiroaki , Okamoto Yoichi , Miyazaki Hisashi , Morimoto Jun 
Published: January 2010

AbstractWe have already reported that Au or B doped SiGe amorphous thin films have superior thermoelectric properties which are attribute to amorphous phase. For the practical use, the bulk materials are required. In this work, we have tried and succeeded to fabricate Si-Ge-B amorphous bulk samples. First, fine particles were prepared by three kinds of mechanical process, such as roller milling method, mechanical alloying method and planetary milling method. It was intended to introduce a large amount of defects and strain into samples and/or gamorphouslization'h. Then, the prepared fine particles were pressed and formed into 2 x 5 x 15 mm^3 samples. Thermoelectric power and electrical resistivity of samples were measured by steady state measurement and four terminal method with temperature range of room temperature to 873 K in N2 flow at atmosphere pressure, respectively. Thermal conductivity was measured by photo-pyroelectric method in room temperature. Some samples have maximum value of thermoelectric power over 10-3 V/K. therefore≤ we were succeeded to prepare bulk materials which have higher thermoelectric power than that of conventional crystal materials. X-ray diffraction measurement and scanning electron microscope observation were performed on fabricated samples. From XRD measurement and SEM observation, the samples were in mixed condition of disordered microcrystals and amorphous state.