bluuebunny/crossref_metadata_2025 huggingface dataset:
Single‐Electron Oxidation of Tungsten Acetylide Complexes [(η5‐C5H5)(CO)(NO)W–C≡C–R]Li
Authors: Ipaktschi Junes , Munz Frank
Published: March 2006

The reaction of a tungsten acetylide complex [(η5‐C5H5)(CO)(NO)W–C≡C–R]Li (1) [1a, R = C6H5; 1b, R = C(CH3)3; 1c, R = Si(CH3)3] with one equivalent of ferrocenium tetrafluoroborate [Cp2Fe][BF4], acting as a one‐electron oxidant in THF at –50 °C, leads to the bimetallic tungsten–alkynyl complexes [(η5‐C5H5)(NO)W–C≡C–R]2 (9) [9a, R = C6H5; 9b, R = C(CH3)3; 9c, R = Si(CH3)3] as pale‐orange crystals. The crystal structure of complex 9a is reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Organic and inorganic di‐cations for capillary silica coating and EOF modulation in CE: Example of application in PEG analysis
Authors: Sebastiano Roberto , Mendieta Martha Elena , Antonioli Paolo , Bossi Alessandra , Righetti Pier Giorgio , Citterio Attilio
Published: March 2006

EOF measurements, by using 1,4‐di‐(4‐aza‐1‐azonia‐bicyclo[2.2.2]octane)butane diiodide, barium and strontium tetraborate as silica wall modifiers, are reported and, as an example of application, analysis of PEG (PEG 400–2000) polydisperse preparations in free solution CZE is shown. PEGs have been derivatized with phthalic anhydride so as to form singly or doubly charged derivatives with strong UV absorbance at 214 nm. Whereas separations in plain tetraborate buffer, pH 9.0, without any EOF control, did not lead to good resolution of all‐size oligomers and suffered from long analysis times, excellent resolution of all oligomers up to 40 ethylene oxide (EO) units could be obtained under EOF control. Such EOF modulation was engendered by addition of 1 mM M7C4M7, a doubly charged organic cation able to stick tenaciously to the silica wall. Further modulation of EOF and silica surface modification could be achieved also by addition of inorganic cations, notably those of group II, whereas monovalent cations did not seem to affect much the EOF flux. Among the doubly charged cations investigated, Ca++, Mg++, Sr++ and Ba++, the latter did seem to offer best EOF control and reproducible runs. A judicious blend of M7C4M7 (0.33–1 mM range) with barium (10–20 mM range) allowed baseline resolution of all PEG oligomers investigated up to PEG 2000 and >40 EO units in length. In this last case, best results in terms of reproducibility and separation efficiency of the more heavy homologues were obtained using Li+ salt in small amounts.
Serum protein pattern during cow pregnancy: Acute‐phase proteins increase in the peripartum period
Authors: Cairoli Fausto , Battocchio Massimiliano , Veronesi Maria Cristina , Brambilla Daniela , Conserva Francesca , Eberini Ivano , Wait Robin , Gianazza Elisabetta
Published: March 2006

Serum collected in a time‐course mode during the pregnancy of a group of heifers was analyzed by 2‐DE under various experimental conditions to optimize resolution of all protein spots. Changes in the levels of some components were detected during the last phase of pregnancy and early postpartum. These included a decrease of α2‐HS‐glycoprotein, an increase of α1‐antichymotrypsin and, with a much larger and more abrupt variation, of orosomucoid and haptoglobin. These findings associate the weeks preceding calving with an acute‐phase reaction. Analysis of individual animal's sera by 1‐DE demonstrated a higher level of orosomucoid in the sera of cows developing postpartum endometritis during the 2 wk after calving (i.e., in the course of the infection) but a lower level during the 2 wk before calving. This observation could represent an important tool for the prepartum detection of animals prone to develop postpartum endometritis and lead to a more accurate peripartum management of those animals.
Biomarker discovery in breast cancer serum using 2‐D differential gel electrophoresis/ MALDI‐TOF/TOF and data validation by routine clinical assays
Authors: Huang Hong‐Lei , Stasyk Taras , Morandell Sandra , Dieplinger Hans , Falkensammer Gerda , Griesmacher Andrea , Mogg Maurice , Schreiber Martin , Feuerstein Isabel , Huck Christian W. , Stecher Guenther , Bonn Guenther K. , Huber Lukas A.
Published: March 2006

In the present study, we used 2‐D differential gel electrophoresis (2‐D DIGE) and MS to screen biomarker candidates in serum samples obtained from 39 patients with breast cancer and 35 controls. First, we pooled the serum samples matched with age and menopausal status. Then, we depleted the two most abundant proteins albumin and IgG by immunoaffinity chromatography under partly denaturing conditions in order to enrich low‐abundance proteins and proteins with low molecular weight. Concentrated and desalted samples were labeled with three different CyDyes including one internal standard, pooled from all the samples, and separated with 2‐D DIGE in triplicate experiments. Biological variations of the protein expression level were analyzed with DeCyder software and evaluated for reproducibility and statistical significance. The profile of differentially expressed protein spots between patients and controls revealed proapolipoprotein A‐I, transferrin, and hemoglobin as up‐regulated and three spots, apolipoprotein A‐I, apolipoprotein C‐III, and haptoglobin α2 as down‐regulated in patients. Finally, routine clinical immunochemical reactions were used to validate selected candidate biomarkers by quantitative determination of specific proteins in all individual serum samples. The serum level of transferrin correlated well with the 2‐D‐DIGE results. However, the serum levels of apolipoprotein A‐I and haptoglobin could not be detected with the clinical routine diagnostic tests. This demonstrated an advantage 2‐D DIGE still has over other techniques. 2‐D DIGE can distinguish between isoforms of proteins, where the overall immunochemical quantification does fail due to a lack of isoform‐special antibodies.
Mathematical Modeling of Size Exclusion Chromatography
Authors: Zelic B. , Nesek B.
Published: March 2006

A mathematical model of the size exclusion chromatography (SEC) process in chromatographic columns has been developed. It considers the following three mass transfer processes in the SEC column: axial dispersion in the bulk‐fluid phase, interfacial film mass‐transfer between the stationary and mobile phases, and diffusion of solutes within the macro pores of the packing particles. Differential equations of the process model were solved by the finite difference method. Characteristics of the column and the packing particles (bed void volume fraction, particle porosity, accessible particle porosity) were obtained experimentally, as well as retention times of different molecules with known molecular weights. Experiments were performed with two different columns containing two different packing materials, Superdex 75 HR 10/30 and BioSep SEC S2000, respectively. The model has been validated by comparing theoretical and experimental retention times for the different columns.
Comparison of the power of the tests in one‐way ANOVA type model with Poisson distributed variables
Authors: Hrdličková Zuzana
Published: March 2006

This article deals with the one‐way ANOVA type generalized linear model, the method most often used if the assumptions of the classical one‐way ANOVA are not satisfied. In particular, the model with Poisson distributed response variables is considered. The article aims at the powers of tests based on the most frequent statistics—deviance, Pearson and score statistic. The asymptotic powers of the considered tests are obtained either analytically or by means of simulation. Afterwards, these powers are compared with powers of the tests obtained by an alternative method—a variance‐stabilizing transformation followed by the classical linear model with known or unknown variance. Finally, a power analysis is carried out on biometrical data to find an experimental design suitable for detecting a priory given differences in expected values. Copyright © 2006 John Wiley & Sons, Ltd.
A Web‐based rainfall atlas for Southern Africa
Authors: Zucchini Walter , Nenadić Oleg
Published: March 2006

We describe the development of a Web‐based rainfall atlas for southern Africa, a decision support system for the management of water resources. The rainfall atlas, which is accessible online at the URIhttp://134.76.173.220/rainfall/index.html, was constructed in a number of phases over some 20 years. In the first phase, a 16 parameter model was developed, validated for representative sites, and then fitted to daily rainfall data from 2550 sites. Eight years later the estimates of the model parameters were updated, extended to 5070 sites, and interpolated on a grid of 1 minute of a degree of latitude and longitude over the entire region of southern Africa, namely South Africa, Lesotho and Swaziland. The method of kriging with external drift was used for the interpolation. The interpolated estimates were used to generate long artificial daily rainfall sequences at a spatial resolution of 1 minute of degree square. The sequences were used to compute rainfall‐related statistics, such as percentiles of annual and monthly rainfall distributions, probabilities associated with droughts, and additional measures relating to the timing and intensity of rainfall. The final phase, information transfer, was the construction of the Atlas website, which offers online access to a wide range of rainfall‐related statistics and some 5000 maps. To facilitate the computation of statistics that are not available in the database, the Atlas enables users to generate, and then import, artificial sequences online, for any grid point in southern Africa. These sequences are designed to mirror the properties of real rainfall records (seasonality, serial dependence, distributional properties, etc.) at the required grid point and can be used to compute quantities of interest empirically. Copyright © 2006 John Wiley & Sons, Ltd.
Pattern analysis of dune‐field parameters
Authors: Ewing Ryan C. , Kocurek Gary , Lake Larry W.
Published: March 2006

As a basic form of pattern analysis, the parameters of dune spacing, defect density, crest orientation and crest length are measured from remote images and treated statistically for dunes at White Sands in New Mexico, the Algodones in California, the Agneitir in Mauritania, and the Namib in Namibia. Statistical populations are identified from frequency plots of dune spacing and crest length, field‐scale calculations of defect density, and rose diagrams of crest orientation. Single populations characterize simple dune fields (White Sands), whereas multiple populations characterize compound/complex dunes (Algodones, Namib), and complex dune fields (Agneitir). As time increases, dune fields show an increase in dune spacing and crest length, a decrease in defect density, more tightly clustered crest orientation, and a reduction in the variance associated with measurements of these parameters. The results are consistent with models of dune fields as self‐organizing complex systems in which a characteristic pattern emerges as a function of constructional time. Because pattern evolution is a function of time, it may be possible to use pattern analysis to augment current methods of age determination. Statistically defined populations can be used in geomorphic backstripping to unstack generations of simple patterns that give rise to complex patterns, and to reconstruct each generation in terms of construction time and palaeo‐wind regime. Copyright © 2006 John Wiley & Sons, Ltd.
Ten Years (1994–2004) of ‘potential’ weathering in Kärkevagge, Swedish Lapland
Authors: Thorn Colin E. , Dixon John C. , Darmody Robert G. , Allen Charles E.
Published: March 2006

This paper reports the findings of a ten‐year study of ‘potential’ weathering of machine‐polished dolomite, granite and limestone discs buried in shallow pits beneath a variety of vegetation cover types in Kärkevagge and on an adjoining ridge in Swedish Lapland. The paper extends a previously published five‐year (1994–1999) record by adding the period 1999–2004, comparing the two periods, and integrating results to provide a decadal record. The field and laboratory procedures of the first period were faithfully replicated during the second period with the notable modification that only a segment of each original disc was replaced in the field for the second portion of the study. A total of 48 dolomite, 36 granite and 19 limestone discs were buried at shallow depths (≤60 cm) beneath alpine tundra, birch forest, Dryas heath, heath, meadow, solifluction meadow and willow cover types. With the exception of the willow, which had only two, each cover type had three replicated pits.

Relationships identified during Period 1 were generally repeated during Period 2. Salient results are the expected weathering rate order of limestone > dolomite > granite, and statistically distinguishable differences in weathering rate by vegetation cover type. Differentiation of the two heath categories from the other vegetation cover types is the most important spatial distinction in weathering rate. Statistical distinctions among other measures were variable, with soil horizon and burial depth being non‐significant, pH variability being weakly distinguishable, and drainage variability being important. Granite mass losses were generally too low to be useful for statistical separation. Dolomite discs experienced a statically higher loss rate during Period 2 which had both a warmer and wetter air climate than Period 1. Minimum and maximum total decadal percentage losses from the discs were 0·2 and 25·7 for dolomite, 0·07 and 0·57 for granite, and 0·2 and 32·1 for limestone. In general, dolomite was the most useful material for monitoring mass loss, with limestone weathering tending to be too rapid and granite weathering being too slow. Copyright © 2006 John Wiley & Sons, Ltd.
Contribution to understanding the historical evolution of meandering rivers using dendrochronological methods: example of the Mała Panew River in southern Poland
Authors: Malik Ireneusz
Published: March 2006

The Mała Panew is a meandering river that flows 20 km through a closed forest. During times of high discharge the riverbed and floodplain are transformed under the influence of riparian trees. The changes provide the opportunity to measure the intensity of erosion and sediment accumulation based on tree ages, the dating of coarse woody debris (CWD) in the riverbed, and the dating of eccentric growth of tilting trees and exposed roots.

The bed and floodplain in reaches of the Mała Panew River with low banks were greatly altered as a result of long periods of flooding between 1960 and 1975. Banks were undercut during these floods and black alders tilted. Those parts of alder crowns or stems which tilt and sink generate small sand shadows. When erosion is intensive alder clumps are undercut from concave banks and become mid‐channel islands, while on the other side of the channel meandering bar levels are created.

The reaches with higher banks were altered by large floods, especially in 1985 and 1997. The concave banks are undercut and sediment with CWD is deposited within the riverbed, forming sand shadows behind the CWD. Copyright © 2006 John Wiley & Sons, Ltd.
Methodological pluralism: The gold standard of STEM evaluation
Authors: Lawrenz Frances , Huffman Douglas
Published: March 2006

This chapter presents the conceptualization that scientific evaluation is a comprehensive concept including both experimental and nonexperimental methods and that a variety of methods are preferred for STEM evaluation and for the field of evaluation as a whole.
Advancing evaluation of STEM efforts through attention to diversity and culture
Authors: Mertens Donna M. , Hopson Rodney K.
Published: March 2006

This chapter examines implications from the application of a transformative lens and the concepts of cultural competency to increase our understanding of how evaluation can contribute to the goal of improving STEM outcomes for underrepresented groups.
An educative, values‐engaged approach to evaluating STEM educational programs
Authors: Greene Jennifer C. , DeStefano Lizanne , Burgon Holli , Hall Jori
Published: March 2006

The major principles and commitments of an educative, values‐engaged approach to STEM educational program evaluation are presented, justified, and illustrated. How this approach addresses key issues in STEM education and advances the field is also discussed.
Local evaluation in multisite STEM programs: Relating evaluation use and program results
Authors: Gullickson Arlen R. , Hanssen Carl E.
Published: March 2006

This chapter uses a program‐level evaluation to assess the characteristics of smaller‐scale project evaluations and their use for project improvement and accountability purposes.
Biomaterials and scaffolds for ligament tissue engineering
Authors: Ge Zigang , Yang Fang , Goh James C. H. , Ramakrishna Seeram , Lee Eng Hin
Published: March 2006

Tissue engineering has achieved much progress in an attempt to improve and recover impaired functions of tissues and organs. Although many studies have been done, progress for tissue‐engineered anterior cruciate ligaments (ACLs) has been slow due to their complex structures and mechanical properties. In this review, the ACL anatomical structure, progresses achieved, material selection, structure design, and future direction have been discussed, while the challenges and requirements from materials and scaffolds are highlighted. There is a considerably huge amount work that needs to be carried out; as such, future direction in ligament tissue engineering is proposed in hope that this review will give information on future ligament tissue engineering. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2006
Repair of 20‐mm long rabbit radial bone defects using BMP‐derived peptide combined with an α‐tricalcium phosphate scaffold
Authors: Saito Atsuhiro , Suzuki Yoshihisa , Kitamura Makoto , Ogata Shin‐Ichi , Yoshihara Yusuke , Masuda Shingo , Ohtsuki Chikara , Tanihara Masao
Published: March 2006

In previous studies, we have reported that the BMP‐2‐derived peptide KIPKASSVPTELSAISTLYL, corresponding to BMP‐2 residues 73–92, binds to a BMP‐2‐specific receptor, and elevates both alkaline phosphatase activity and osteocalcin mRNA in the murine mesenchymal cell line, C3H10T1/2. This 73–92 peptide conjugated to a covalently crosslinked alginate gel induced ectopic bone formation in rat calf muscle, and activated osteoblasts to promote the repair of rat tibial bone defects. Here, we report repair of 20‐mm long rabbit radial bone defects using the 73–92 peptide combined with a porous α‐tricalcium phosphate (TCP) scaffold. In vitro, the 73–92 peptide was released from the porous α‐TCP scaffold over more than one week. In vivo, radiomorphometric analysis showed that the 73–92 peptide combined with the porous α‐TCP scaffold promoted calcification in the implanted area in a dose‐dependent manner, and that 5 mg of the 73–92 peptide induced connection of 20‐mm long defects, defects of critical size, 12 weeks after implantation. Histological examination revealed newly formed bone and a marrow cavity in the implanted area. The area of bone denser than 690 mg/cm3 induced by the 73–92 peptide was nearly equal to that of the contralateral radius. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Osteoinduction by biomaterials—Physicochemical and structural influences
Authors: Habibovic Pamela , Sees Tara M. , van den Doel Mirella A. , van Blitterswijk Clemens A. , de Groot Klaas
Published: March 2006

Osteoinduction by biomaterials has been shown to be a real phenomenon by many investigators in the last decade. The exact mechanism of this phenomenon is, however, still largely unknown. This in vivo study in goats was performed to get insight into processes governing the phenomenon of osteoinduction by biomaterials and had four main goals: (i) to further investigate the influence of physicochemical properties and structure on biomaterial osteoinductive potential, (ii) to investigate the influence of implant size on the amount of induced bone, (iii) to investigate implantation site dependence, and (iv) to investigate changes occurring on the surface of the material after implantation. Intramuscular implantations of four different biphasic calcium phosphate ceramics, consisting of hydroxyapatite and β‐tricalcium phosphate and a carbonated apatite ceramic, indicated that, for a maximal osteoinductive potential, there is an optimal specific surface area for each material type. It was further shown that a decrease of the implant size with a half significantly decreased the relative amount of induced bone. In addition, subcutaneous implantation did not give rise to ectopic bone formation in any of the animals, while bone was induced in most animals intramuscularly. Analysis of the surfaces of the materials after subcutaneous implantation inside diffusion chambers indicated that the increased specific surface area leads to more surface reactivity, which is hypothesized to be essential for osteoinductivity by biomaterials. © 2006 Wiley Periodicals, Inc. J Biomed Master Res, 2006
Linear‐scaling molecular orbital calculations for the pKa values of ionizable residues in proteins
Authors: Ohno Kazuki , Sakurai Minoru
Published: March 2006

In this report, we present a computational methodology for the pKa prediction of proteins, based on linear‐scaling molecular orbital calculations for their solution‐conformations obtained from NMR measurements. The method is used to predict the pKa values of five carboxylic acids (Asp7, Glu10, Glu19, Asp27, and Glu43) in turkey ovomucoid third domain (OMTKY3), and six aspartates residues (Asp 22, Asp 44, Asp 54, Asp 75, Asp 83, and Asp 93) in barnase. For OMTKY3, all the predicted pKa values are within 1 pH units from the available experimental ones, except for the case of Glu 43. For barnase, the root‐mean‐square deviation from experiment is 1.46 pH units. As a result, the proposed pKa calculation method correctly reproduces the relative order of the pKa values among the carboxylic acids located in different sites of the proteins. The calculated pKa values are decomposed into the contributions of short‐ and long‐range structural difference effects. The results indicate that in both proteins the pKa value of the given carboxylic acid is partially influenced by long‐range interactions with distant charged residues, which significantly contribute to determining the relative order of the pKa values. The current methodology based on LSMO provides us useful information about the titration behavior in a protein. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 906–916, 2006
Theoretical study on the mechanism of the CH2F + NO2 reaction
Authors: Zhang Jia‐Xu , Li Ze‐Sheng , Liu Jing‐Yao , Sun Chia‐Chung
Published: March 2006

Despite the importance of the Fluoromethyl radicals in combustion chemistry, very little experimental information on their reactions toward stable molecules is available in the literature. Motivated by recent laboratory characterization about the reaction kinetics of Chloromethyl radicals with NO2, we carried out a detailed potential energy survey on the CH2F + NO2 reaction at the B3LYP/6‐311G(d,p) and MC‐QCISD (single‐point) levels as an attempt toward understanding the CH2F + NO2 reaction mechanism. It is shown that the CH2F radical can react with NO2 to barrierlessly generate adduct a (H2FCNO2), followed by isomerization to b1 (H2FCONO‐trans) which can easily interconvert to b2 (H2FCONO‐cis). Subsequently, Starting from b (b1, b2), the most feasible pathway is the CF and NO1 bonds cleavage along with NF bond formation of b (b1, b2) leading to P1 (CH2O + FNO), or the direct NO1 weak‐bond fission of b (b1, b2) to give P2 (CH2FO + NO), or the 1,3‐H‐shift associated with NO1 bond rupture of b1 to form P3 (CHFO + HNO), all of which may have comparable contribution to the reaction CH2F + NO2. Much less competitively, b2 either take the 1,4‐H‐shift and O1N bond cleavage to form product P4 (CHFO + HON) or undergo a concerted H‐shift to isomer c2 (HFCONOH), followed by dissociation to P4. Because the rate‐determining transition state (TSab1) in the most competitive channels is only 0.3 kcal/mol higher than the reactants in energy, the CH2F + NO2 reaction is expected to be rapid, and may thus be expected to significantly contribute to elimination of nitrogen dioxide pollutants. The similarities and discrepancies among the CH2X + NO2 (X = H, F, and Cl) reactions are discussed in terms of the electronegativity of halogen atom. The present article may assist in future experimental identification of the product distributions for the title reaction, and may be helpful for understanding the halogenated methyl chemistry. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 894–905, 2006
Ethylene glycol diglycidyl ether as a protein cross‐linker: a case study for cross‐linking of hemoglobin
Authors: Lu Xiuling , Xu Yuhong , Zheng Chunyang , Zhang Guifeng , Su Zhiguo
Published: March 2006

Being widely applied in the chemical industry, ethylene glycol diglycidyl ether (EGDE) was tried as a protein cross‐linker for cross‐linking of bovine hemoglobin (Hb). The characteristics of the reaction and the products were studied using electrophoresis and multi‐angle laser light scattering coupled with HPLC. At pH 7.5, EGDE could react with the sulfhydryl group and the ε‐amino group, but reacted preferentially with the sulfhydryl group. As the pH increased from 7.5 to 9.5, the reaction took place mainly between the amino groups and EGDE. By controlling the pH and other conditions, intra‐ and inter‐molecularly cross‐linked products with narrow size distribution were obtained. The intramolecular product was about 90% of the reaction mixture. The intermolecularly cross‐linked Hb consisted of 74.7% of dimeric Hb with weight‐average molecular weights (Mw) of 146 kDa, 18.9% of trimeric Hb with Mw of 228 kDa, and 6.4% of oligomer with four to six Hb units, Mw of 375 kDa. The cross‐linking altered the oxygen affinity (P50) and the Hill coefficient of Hb but they are within the range of hemoglobin‐based red cell substitutes. The pI of intramolecularly and intermolecularly cross‐linked Hb increased from 6.7–7.4 to 6.9–7.6 and 8.2–8.8 respectively. The study demonstrated that EGDE could be an alternative to glutaraldehyde for cross‐linking of hemoglobin and other proteins on a large‐scale without significantly impairing the biological activity. Copyright © 2006 Society of Chemical Industry
Enhanced photodegradation of bisphenol A in the presence of β‐cyclodextrin under UV light
Authors: Wang Guanghui , Wu Feng , Zhang Xu , Luo Mingdao , Deng Nansheng
Published: March 2006

Enhancement of the photodegradation of bisphenol A (BPA) by β‐cyclodextrin (β‐CD) was investigated under a 30 W UV disinfection lamp (λmax = 254 nm). The photodegradation rate of BPA in aqueous solutions with β‐CD was faster than that in aqueous solutions without β‐CD; for example, after 50 min of UV irradiation, β‐CD had increased the photodegradation efficiency by about 46.5% for 10 mg dm−3 BPA. The photodegradation of 2.5–20 mg dm−3 BPA in aqueous solutions was found to follow pseudo‐first‐order kinetics. The first‐order rate constant showed a 12‐fold increase in the presence of β‐CD. Factors such as β‐CD concentration, pH, BPA initial concentration and organic solvent influencing the photodegradation of BPA were studied and are described in detail. Variations in the pH and electrical conductivity of solutions were observed during the photodegradation process. The enhancement of photodegradation of BPA results mainly from the lower bond energy between some atoms in the BPA molecule after inclusion interaction with β‐CD. Copyright © 2006 Society of Chemical Industry
Multidecadal climate variability of global lands and oceans
Authors: McCabe Gregory J. , Palecki Michael A.
Published: March 2006

Principal components analysis (PCA) and singular value decomposition (SVD) are used to identify the primary modes of decadal and multidecadal variability in annual global Palmer Drought Severity Index (PDSI) values and sea‐surface temperatures (SSTs). The PDSI and SST data for 1925–2003 were detrended and smoothed (with a 10‐year moving average) to isolate the decadal and multidecadal variability. The first two principal components (PCs) of the PDSI PCA explained almost 38% of the decadal and multidecadal variance in the detrended and smoothed global annual PDSI data. The first two PCs of detrended and smoothed global annual SSTs explained nearly 56% of the decadal variability in global SSTs. The PDSI PCs and the SST PCs are directly correlated in a pairwise fashion. The first PDSI and SST PCs reflect variability of the detrended and smoothed annual Pacific Decadal Oscillation (PDO), as well as detrended and smoothed annual Indian Ocean SSTs. The second set of PCs is strongly associated with the Atlantic Multidecadal Oscillation (AMO). The SVD analysis of the cross‐covariance of the PDSI and SST data confirmed the close link between the PDSI and SST modes of decadal and multidecadal variation and provided a verification of the PCA results. These findings indicate that the major modes of multidecadal variations in SSTs and land‐surface climate conditions are highly interrelated through a small number of spatially complex but slowly varying teleconnections. Therefore, these relations may be adaptable to providing improved baseline conditions for seasonal climate forecasting. Copyright © 2006 John Wiley & Sons, Ltd.
Effects of surface heating over Indochina and India landmasses on the summer monsoon over South China
Authors: Chow K. C. , Liu Yiming , Chan Johnny C. L. , Ding Yihui
Published: March 2006

Sensitivity experiments have been performed using a regional climate model to study the effect of land‐surface heating over the Indochina and Indian Peninsulas on the summer monsoon over South China. The term surface heating is defined here as the sum of sensible heat flux and net flux of longwave radiation from the surface. In each sensitivity experiment, the surface heating over the land surface of the region considered is cut off, but evaporation over the land surface and latent heat release are still permitted.

Compared with that of the Indian Peninsula, surface heating over the Indochina Peninsula has a much more significant effect on both the monsoon circulation and precipitation over South China and the East Asia regions, particularly during the onset period of the summer monsoon over South China. The effect of this surface heating on the vertical velocity over Indochina extends much deeper into the upper troposphere. Precipitation is reduced significantly not only locally, but also extends to South China, as well as the remote regions of East China and the western North Pacific. The variations in geopotential height fields in the lower troposphere and the zonal wind field in the upper troposphere suggest that the surface heating over Indochina may have an important effect on the strength of the subtropical high, and is closely related to the onset of the South China Sea summer monsoon.

On the other hand, the surface‐heating effect of the Indian Peninsula on precipitation as well as the monsoon circulation is found to be relatively local and mainly affects the Bay of Bengal region. Copyright © 2006 Royal Meteorological Society.
Glycosidic aroma compounds of some Portuguese grape cultivars
Authors: Cabrita Maria João , Freitas Ana M Costa , Laureano Olga , Stefano Rocco Di
Published: March 2006

In order to evaluate the potential aroma of some Portuguese grapes, several glycosidically bound aroma compounds of ten grape varieties grown in Évora, Alentejo, Portugal, were released, identified and quantified using gas chromatography–mass spectrophotometry. White varieties were Arinto, Perrum, Rabo‐de‐Ovelha, Roupeiro and Antão Vaz. Red varieties were Trincadeira, Aragonez, Tinta Caiada, Moreto and Castelão. Grapes of Roupeiro and Trincadeira from five other vines in the Alentejo region were also studied. For each variety pulp and skin were analyzed separately. The compounds produced by enzymatic hydrolysis of glycoside precursors extracted from pulps and skins of these grapes were similar to the ones appearing in the so‐called ‘aromatic’ varieties; however, the amounts found were significantly lower. These results seem to show the neutral characteristic of these grapes to indicate that each variety has a distinctive profile regarding compounds from the linalool class. The ratios of trans : cis forms of some linalool compounds remain the same in all samples of Roupeiro and Trincadeira, regardless their origin. In Trincadeira grapes no linalool was detected. Skins are always richer than pulps. The acid hydrolysis of norisoprenoid aglycons produced highly odorant compounds previously described in grape varieties. Although some differences between varieties could be detected, the red grapes Aragonez and Castelão are richer in vitispiranes while Moreto, Trincadeira and Tinta Caiada are richer in actinidols; in white grapes, only Roupeiro and Perrum show detectable amounts of vitispiranes. These results need further investigation and analysis to be considered as a statement and should be confirmed in an extended study. Copyright © 2006 Society of Chemical Industry
Urea treatment of whole‐crop triticale at four growth stages: effects on chemical composition and on in vitro digestibility of cell wall
Authors: Guedes Cristina M , Rodrigues Miguel M , Gomes Maria J , Silva Severiano R , Ferreira Luís M , Mascarenhas‐Ferreira Armando
Published: March 2006

The objective of this study was to evaluate the preservative and upgrading potential of urea added to whole‐crop triticale. Triticale, harvested at different growth stages according to Feekes' scale (10.51, 10.54, 11.1 and 11.2), was ensiled with four levels of urea (0, 30, 60 and 90 g kg−1 dry matter (DM)) and stored in plastic bags for 60 days. Data were analysed as a factorial design with growth stage and urea level as the main factors. Urea was extensively hydrolysed (more than 90% of added urea). Urea breakdown was not affected by urea level (P > 0.05) but decreased significantly with growth stage (P < 0.001). Microbial activity measured by pH, volatile fatty acid production and total non‐structural carbohydrate concentration was significantly reduced by the urea level. Urea treatment significantly (P < 0.001) increased water‐soluble and ammonium nitrogen; more than 85% of the added nitrogen was retained. Application of urea at a rate of 60 and 90 g kg−1 DM significantly (P < 0.05) reduced the neutral detergent fibre (NDF) content and increased (P < 0.05) the NDF and acid detergent fibre in vitro digestibility. Whole‐crop triticale harvested at later growth stages (approximately 60% DM) can be effectively preserved and upgraded by ensiling with 60–90 g urea kg−1 DM. Copyright © 2006 Society of Chemical Industry
Sensorial and chemical changes in honey roasted peanuts and roasted peanuts stored under different temperatures
Authors: Nepote Valeria , Mestrallet Marta G , Ryan Liliana , Conci Silvia , Grosso Nelson R
Published: March 2006

The purpose of this work was to determine the oxidative stability in honey roasted peanuts (HRP) and roasted peanuts (RP). Chemical analysis and descriptive analysis were performed on samples of HRP and RP stored at −15, 23 and 40 °C. The chemical analyses, peroxide and thiobarbituric acid reactive substance (TBARS) values, and the descriptive analysis were performed during 126 days of storage to determine protective effect of honey coating on the product stability. Peroxide and TBARS values, oxidized and cardboard flavors increased and roasted peanutty flavor decreased across the storage time for both products. Addition of honey coating provided protection against lipid oxidation. Peroxide value reached 10 meqO2 kg−1 after 6 days in RP and 36 days in HRP at 23 °C. Copyright © 2006 Society of Chemical Industry
Effect of solution pH on solubility and some structural properties of soybean protein isolate films
Authors: Mauri Adriana N , Añón María C
Published: March 2006

Changes in solubility and molecular properties of protein films obtained from soy protein isolate (SPI) solutions at different pH values (2, 8 and 11) were investigated to study protein behavior during film formation. Proteins retained their native conformation in films at pH 8, but were partially or extensively denatured at pH 11 and 2. Although film protein networks were maintained by the same type of interactions at different pH values—covalent (disulfide bonds) and non‐covalent bonds (especially hydrophobic interactions and hydrogen bonds)—the intensity of each type of interaction (predicted from solubility tests in buffers with different chemical action) depended on the pH of the initial solution. Films obtained at pH 8 presented the highest solubility in all the buffers, whereas films at formed pH 2 presented the lowest, except in the buffer of pH 8 that contained urea, SDS and 2‐mercaptoethanol, which totally dissolved 100% of the film proteins. Films prepared at extreme pH values had a denser microstructure than those at pH 8. SDS–PAGE patterns indicated that films were mainly formed by β‐conglycinin and glycinin, which aggregated in different forms during film formation, depending on the pH of the initial solutions. Some of these proteins remained weakly bonded and/or were held by the network of films. These differences in the protein networks structure would affect the physical, mechanical and barrier properties of the films. Copyright © 2006 Society of Chemical Industry
Gas‐phase rate coefficients for the reactions of O(3P), S(3P), Se(3P), and Te(3P) with alkenes: Application of perturbation frontier molecular orbital theory, correlations, and structure–activity relations (SARs)
Authors: Pfrang Christian , King Martin D. , Canosa‐Mas Carlos E. , Wayne Richard P.
Published: March 2006

The kinetics of the reactions of the atoms O(3P), S(3P), Se(3P), and Te(3P) with a series of alkenes are examined for correlations relating the logarithms of the rate coefficients to the energies of the highest occupied molecular orbitals (HOMOs) of the alkenes. These correlations may be employed to predict rate coefficients from the calculated HOMO energy of any other alkene of interest. The rate coefficients obtained from the correlations were used to © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 351–356, 2006
Fever, mental impairment, acute anemia, and renal failure in patient undergoing orthotopic liver transplantation: Posttransplantation malaria
Authors: Menichetti Francesco , Bindi Maria Lucia , Tascini Carlo , Urbani Lucio , Biancofiore Gianni , Doria Roberta , Esposito Massimo , Mozzo Roberto , Catalano Gabriele , Filipponi Franco
Published: March 2006

A case of post-transplant malaria is described. The patient presented fever and severe anemia after orthotopic liver transplantation. Diagnosis was made only after the review of donor characteristics. Although a high parasitemia was found at the moment of diagnosis, the treatment with quinine and doxycycline was successful. Donor epidemiology should always be considered for a prompt diagnosis of rare tropical diseases in the graft recipients.
Liver Transpl 12:674–676, 2006.

© 2006 AASLD.
Live donor liver transplantation
Authors: Florman Sander , Miller Charles M.
Published: March 2006

With ever-increasing demand for liver replacement, supply of organs is the limiting factor and a significant number of patients die while waiting. Live donor liver transplantation has emerged as an important option for many patients, particularly small pediatric patients and those adults that are disadvantaged by the current deceased donor allocation system. Ideally there would be no need to subject perfectly healthy people in the prime of their lives to a potentially life-threatening operation to procure transplantable organs. Donor safety is imperative and cannot be compromised regardless of the implication for the intended recipient. The evolution of split liver transplantation is the basis upon which live donor transplantation has become possible. The live donor procedures are considerably more complex than whole organ decreased donor transplantation and there are unique considerations involved in the assessment of any specific recipient and donor. Donor selection and evaluation have become highly specialized. The critical issue of size matching is determined by both the actual size of the donor graft and the recipient as well as the degree of recipient portal hypertension. The outcomes after live donor liver transplantation have been at least comparable to those of deceased donor transplantation. Nevertheless, all efforts should be made to improve deceased donor donation so as to minimize the need for live donors. Transplant physicians, particularly surgeons, must take responsibility for regulating and overseeing these procedures.
Liver Transpl 12:499–510, 2006.

© 2006 AASLD.
Morphological Behaviour of Thermoplastic Polyurethanes During Repeated Deformation
Authors: Laity Peter R. , Taylor Jennifer E. , Wong Steven S. , Khunkamchoo Peck , Cable Martin , Andrews Geoffrey T. , Johnson Anthony F. , Cameron Ruth E.
Published: March 2006

Summary: SAXS was used to investigate the morphological responses of two commercial thermoplastic poly(ether‐co‐urethane) elastomers during repeated uniaxial extension and stress‐relaxation at constant strain. Experimental data was analysed using a ‘globular’ morphological model, which has previously been shown to provide a good interpretation of the SAXS from these polymers. The results indicated that microdomain rotation and fragmentation coincided with and may have contributed to the strain‐softening observed during the initial deformation cycles and stress relaxation. However, these morphological changes appeared to be largely reversed, when the material was allowed to retract; consequently, they appeared insufficient to account for the dramatic changes in mechanical properties and permanent set observed between the first and second extension cycles. One possible explanation is that the mechanical properties may have been dominated by a few, larger microdomains that were too large to be observed by SAXS. Alternatively, the considerable changes in scattering intensity suggested a mechanism based on the slippage of entanglements as a result of strain‐induced segmental mixing.

2D‐SAXS patterns of poly(ether‐co‐urethane)s during second uniaxial extension.

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2D‐SAXS patterns of poly(ether‐co‐urethane)s during second uniaxial extension.
Calixarene Derivatives as Novel Nanopore Generators for Templates of Nanoporous Thin Films
Authors: Yim Jin‐Heong , Kim Jongseob , Gidley David. W. , Vallery Richard S. , Peng Hua‐Gen , An Duk Keun , Choi Byoung‐Ki , Park Young‐Kwon , Jeon Jong‐Ki
Published: March 2006

Summary: We report herein calixarene derivatives, which could adapt to various fields of application, as novel pore generators for making nanoporous materials. The pore structure of nanoporous materials exhibits disordered pores with small mesopore diameter (2–3 nm), which is similar to the micelle‐like assembled structure of the calixarene compounds. The electro‐optical properties such as dielectric constants and refractive indexes of these porous thin films can easily be manipulated. The calixarene‐templated nanoporous films could find a variety of potential applications, such as low‐dielectric constant (k) materials and high‐surface area materials for catalysis and biotechnology.

PM3‐optimized structures of CA[4] and CA[6].

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PM3‐optimized structures of CA[4] and CA[6].
Synthesis and Photopolymerizations of New Crosslinkers for Dental Applications
Authors: Yagci Baris , Ayfer Burcu , Albayrak Aylin Z. , Avci Duygu
Published: March 2006

Summary: Five new crosslinkers for use in dental composites were synthesized. Four are based on TBHMA: 1 via reaction of TBBr and Bisphenol A; 2 by hydrolysis of t‐butyl groups of the first monomer to give a diacid derivative; 3 by conversion of the first monomer to an amide derivative using benzyl amine; 4 by conversion of the first monomer to amide derivative using APTES. The AHM‐based monomer 5 was synthesized from the Michael addition of APTES to AHM. The photopolymerization behaviors of the synthesized monomers with Bis‐GMA, TEGDMA and HEMA were investigated using photodifferential scanning calorimetry at 40 °C using DMPA as photoinitiator. The polymerization rates and degrees of conversion for mixtures of any of the monomers 1–4 with Bis‐GMA:TEGDMA were found to be similar to Bis‐GMA:TEGDMA, higher than Bis‐GMA:HEMA, and also higher than mixtures with Bis‐GMA:HEMA. The incorporation of TBHMA‐based monomers into the conventional resin mixture (Bis‐GMA and TEGDMA) reduced the polymerization shrinkages. Monomer 5 and its mixtures polymerized much faster and to higher degrees of conversion than the other investigated systems, however, this system exhibited the largest volume shrinkage.

Structures of some of the new crosslinkers synthesized.

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Structures of some of the new crosslinkers synthesized.
Striatal subregional 6‐[18F]fluoro‐L‐dopa uptake in early Parkinson's disease: A two‐year follow‐up study
Authors: Brück Anna , Aalto Sargo , Nurmi Elina , Vahlberg Tero , Bergman Jörgen , Rinne Juha O.
Published: March 2006

Thirty‐one drug‐naive patients with Parkinson's disease (PD) underwent 6‐[18F]fluoro‐L‐dopa (F‐dopa) positron emission tomography (PET) scan at the time of the diagnosis (baseline) and 2 years later in order to investigate F‐dopa uptake in striatal and extrastriatal regions during the first years of early PD. Twenty‐four healthy controls underwent one F‐dopa PET scan. The regional differences in the striatal and extrastriatal regions were analyzed with statistical parametric mapping and automated region of interest analyses. Our study shows that the F‐dopa uptake in unmedicated early PD is most severely decreased in the dorsal part of caudal putamen but significant decrease can be seen throughout the striatum compared with controls. During the first years of PD, there is a progressive regional decline in striatal F‐dopa uptake, the dorsal part of caudal putamen being still the most severely affected region. The absolute decline is equal between the striatal subregions. This suggests that the decline of dopamine function starts from the dorsocaudal putamen, but once started, the rate of progression is equal between the subregions of the striatum. In contrast to the striatal decline, the increased cortical F‐dopa uptake prevails at least during the first years of PD. © 2006 Movement Disorder Society
Nonsteroidal anti‐inflammatory drugs and risk of Parkinson's disease
Authors: Ton Thanh G. , Heckbert Susan R. , Longstreth W.T. , Rossing Mary Anne , Kukull Walter A. , Franklin Gary M. , Swanson Phillip D. , Smith‐Weller Terri , Checkoway Harvey
Published: March 2006

Inflammation and oxidative stress have been implicated as pathogenic mechanisms in Parkinson's disease (PD). Evidence from in vitro and animal studies suggests a possible protective role of nonsteroidal anti‐inflammatory drugs (NSAIDs), including aspirin. We investigated the risk of PD associated with use of aspirin and nonaspirin NSAIDs in a population‐based case‐control study among enrollees of Group Health Cooperative, a health maintenance organization in the Seattle area. Subjects included 206 cases between ages 35 and 89 with a new diagnosis of idiopathic PD between 1992 and 2002, and 383 randomly selected controls frequency‐matched by age, sex, duration of enrollment, and clinic. We obtained information on participants' age, smoking, and medical history from interview. Exposure to NSAIDs was ascertained from an automated pharmacy database. Medications filled within 5 years of the interview were excluded. After adjusting for age, sex, smoking, duration of enrollment, and clinic, the risk of PD among individuals who received nonaspirin NSAIDs between 1977 and 1992 was 0.90 (95% CI: 0.59–1.35) and 1.67 (95% CI: 0.60–4.60) between 1993 and 2002. Use of ibuprofen was not associated with PD (OR: 0.89; 95% CI: 0.60–1.32). The risk of PD associated with aspirin or aspirin‐containing medications was 0.74 (95% CI: 0.49–1.12). We observed no trend in risk according to number of fills for these drugs. Our results provide only limited support for the hypothesis that use of aspirin may reduce the risk of this disease, and no indication of protection from other NSAIDs. © 2006 Movement Disorder Society