bluuebunny/crossref_metadata_2025 huggingface dataset:
Organocatalytic Asymmetric Mannich Reactions: New Methodology, Catalyst Design, and Synthetic Applications
Authors: Ting Amal , Schaus Scott E.
Published: August 2007

The direct, asymmetric Mannich reaction catalyzed by small organic molecules offers a facile route to optically active α‐ or β‐amino acid derivatives and 1,2‐ and γ‐amino alcohols. One‐pot reactions of unmodified carbonyl donors with preformed or in situ generated imines can be stereochemically controlled with Organic catalysts such as proline, chiral pyrrolidines, chiral Brønsted acids, and Cinchona alkaloids. The generated Mannich adducts can be further functionalized towards a variety of bioactive molecules. In this Microreview, recent contributions are discussed to present the methodology and synthetic advantages achieved so far in the asymmetric Mannich reaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Redox Behavior of Anthocyanins Present in Vitis vinifera L.
Authors: Janeiro Patricia , Brett Ana Maria Oliveira
Published: August 2007

Voltammetric techniques were employed to study the electrochemical behavior of several anthocyanins. The redox behavior of anthocyanins with the same basic structure, the influence of glycosylation on the redox behavior of anthocyanins derived from different anthocyanidins, and the influence of methoxylation were investigated. The anthocyanins used in this study were malvidin‐3‐O‐glucoside chloride, malvidin‐3,5‐di‐O‐glucoside chloride, cyanidin‐3‐O‐glucoside chloride, cyanidin‐3,5‐di‐O‐glucoside chloride, peonidin‐3‐O‐glucoside chloride, delphinidin‐3‐O‐glucoside chloride and the anthocyanidin petunidin chloride, all of them present in Vitis vinifera L. All hydroxyl groups of the anthocyanins can be electrochemically oxidized and the anthocyanins studied revealed a complex and pH dependent oxidation process, with the occurrence of adsorption and of oxidation products blocking the electrode surface.
Electrochemical Genoassay Design for Allele‐Specific Detection of Toll‐Like Receptor‐2 Gene Polymorphism
Authors: Kara Pinar , Cavdar Seda , Berdeli Afig , Ozsoz Mehmet
Published: August 2007

An allele‐specific voltammetric genoassay for the detection of allele‐specific toll‐like receptor‐2 gene arg753gln polymorphism (TLR‐2) from polymerase chain reaction (PCR) amplified real samples was described in this study. Meldola blue (MDB), an intercalator molecule, was used as hybridization label. The wild‐type and mutant type oligonucleotide probes were immobilized onto disposable graphite electrode surfaces by covalent attachment method. The extent of hybridization between probe and target sequences was determined by using differential pulse voltammetry (DPV). As a result of the interaction between MDB and DNA at electrode surface, the MDB signal observed from probe sequence before hybridization and after hybridization with MM sequence is lower than that observed after hybridization with complementary sequence. The differences between the MDB reduction peaks obtained from probe modified, hybrid modified and MM modified electrode were used to detect TLR‐2 from PCR amplified real samples. The discrimination of homozygous and heterozygous alleles was also established by comparing the peak currents of MDB reduction signals. Numerous factors affecting the target hybridization and indicator binding reactions are optimized to maximize the sensitivity.
Chitosan Incorporating Cetyltrimethylammonium Bromide Modified Glassy Carbon Electrode for Simultaneous Determination of Ascorbic Acid and Dopamine
Authors: Zou Xuelian , Luo Liqiang , Ding Yaping , Wu Qingsheng
Published: August 2007

Simultaneous determination of a neurotransmitter, dopamine (DA), and ascorbic acid (AA) is achieved at neutral pH on a chitosan incorporating cetyltrimethylammonium bromide (CTAB) modified glassy carbon (GC) electrode. Differential pulse voltammetry (DPV) technique was used to investigate the electrochemical response of DA and AA at a glassy carbon electrode modified with chitosan incorporating CTAB. An optimum 6.0 mmol L−1 of CTAB together with 0.5 wt% of chitosan was used to improve the resolution and the determination sensitivity. In 0.1 mol L−1 aqueous phosphate buffer solution of pH 6.8, the chitosan‐CTAB modified electrode showed a good electrocatalytic response towards DA and AA. The anodic peak potential of DA shifted positively, while that of AA shifted negatively. Thus, the difference of the anodic peaks of DA and AA reached 0.23 V, which was enough to separate the two anodic peaks very well. The presented method herein could be applied to the direct simultaneous determination of DA and AA without prior treatment. The anodic peak currents (Ipa) of DPV are proportional to DA in the concentration range of 8 μM to 1000 μM, to that of AA 10 μM to 2000 μM, with correlation coefficients of 0.9930 and 0.9945, respectively. The linear range is much wider than previously reported.
Electrochemical Biosensors for Pollutants in the Environment
Authors: Badihi‐Mossberg Michal , Buchner Virginia , Rishpon Judith
Published: August 2007

This article reviews recent advances in electrochemical biosensing and detection of environmental pollutants. Electrochemical biosensors offer precision, sensitivity, rapidity, and ease of operation for on‐site environmental analysis. An electrochemical biosensor is an analytical device in which a specific biological recognition element (bioreceptor) is integrated within or intimately associated with an electrode (transducer) that converts the recognition event to a measurable electrical signal for the purpose of detecting a target compound (analyte) in solution. This approach not only provides the means for on‐site analysis but also removes the time delay and sample alteration that can occur during transport to a centralized laboratory. We first address the basic principles of merging of electrochemistry and biology into a biosensing system, and then we discuss various environmental monitoring strategies involving this technology.
Identification of Earth Pigments by Applying Hierarchical Cluster Analysis to Solid State Voltammetry. Application to Severely Damaged Frescoes
Authors: Doménech Antonio , Doménech‐Carbó María Teresa , Edwards Howell G. M.
Published: August 2007

Multivariate chemometric methods are applied for identifying earth pigments from square‐wave voltammetric measurements performed at pigment‐modified paraffin‐impregnated graphite electrodes allowing for a separation between hematite‐based earths, French ochres, Spanish ochres, siennas, umbers and green earths. This methodology is applied to the identification of the pigments in samples from the ceiling frescoes of Antonio Palomino (dated 1707) in the vaulted nave of the Sant Joan del Mercat church in Valencia (Spain). These frescoes suffered considerable damage by fire during the Spanish Civil War in 1936, resulting in severe chemical and chromatic alterations. Electrochemical data, supported by scanning electron microscopy/energy dispersive X‐ray microanalysis and Raman spectroscopy, indicate that thermal stress induced the transformation of goethite‐based yellow ochres into hematite and magnetite.
An Ionic‐Liquid Based Probe for the Sequential Preconcentration from Headspace and Direct Voltammetric Detection of Phenols in Wastewaters
Authors: Toniolo Rosanna , Pizzariello Andrea , Susmel Sabina , Dossi Nicolò , Doherty Andrew P. , Bontempelli Gino
Published: August 2007

A conveniently assembled probe is here proposed for the electrochemical detection of the phenol index (total volatile phenols) in wastewaters, which exploits some advantageous properties of ionic liquids (ILs), such as their negligible vapor pressure, good electrical conductivity and ability to dissolve a wide range of organic and inorganic compounds. It consists of three Pt wires piercing through a Teflon rod, whose exposed end is coated with an adhesive film of ionic liquid which assured the necessary ionic conductivity between the electrodes while displaying concomitantly good solvent properties. The electrode assembly was exposed to the headspace in equilibrium with wastewater samples for controlled times, until a convenient preconcentration of volatile phenols was achieved. At the end of this step, voltammetric detection was directly performed in situ. The performance of this device was assayed in both phenol synthetic samples and in real wastewaters, after that the preconcentration step was optimized with regard to the effect of pH of the sample, preconcentration time, sample and probe temperature and nature of IL. Voltammetric responses characterized by good repeatability (±4%) were recorded, whose height and area depended linearly on the phenol concentration over a wide range (ca. 3 orders of magnitude). The detection limit, estimated for a signal‐to‐noise ratio of 3 (2 μM at 20 °C and 0.2 μM at 80 °C), was lower than the limit set by the European Community for phenols in wastewaters (ca. 5 μM). The results found in real samples were in acceptable agreement with those obtained by the 4‐aminoantipyrine colorimetric approach which is recommended as the standard method.
Relationship between drought and solar irradiation variables
Authors: Sirdas Sevinc , Sahin Ahmet Duran
Published: August 2007

Drought prediction for in many regions of the world has critical importance for strategic planning agriculture and water management. The occurrence of droughts cannot be predicted with certainty and thus must be treated as random variables. It is the main purpose of this paper to develop a new concept of drought features assessments based on triple drought related hydrometeorological and meteorological variables, namely, rainfall, solar irradiation and sunshine duration. Equal standard rainfall lines are drawn as a map with two reference variables as solar irradiation and sunshine duration. These are referred to as the triple graphical method (TGM) approach. It furnishes rich features of drought behaviour variation based on the rainfall, solar irradiation and sunshine duration. This analysis and the solar irradiation estimation method are applied to seven climatologically different stations in the Republic of Turkey for the monthly data period 1982–1991. The linear relations between drought and the variables of the Angström equation are found between 55% and 94% without Trabzon. Drought and Angström equation parameters are estimated by the proposed methodology. Relations between monthly drought and Angström equation variables are presented by the triple solar‐drought graphical method. TGM provides information about the drought occurrences for different combinations of solar irradiation and sunshine duration. TGM graphs help to identify not only precipitation surplus (wet spells) or deficits (dry spells droughts) but also their variations with two more meteorological variables as solar irradiation and sunshine duration. Copyright © 2007 John Wiley & Sons, Ltd.
The cold regions hydrological model: a platform for basing process representation and model structure on physical evidence
Authors: Pomeroy J. W. , Gray D. M. , Brown T. , Hedstrom N. R. , Quinton W. L. , Granger R. J. , Carey S. K.
Published: August 2007

After a programme of integrated field and modelling research, hydrological processes of considerable uncertainty such as snow redistribution by wind, snow interception, sublimation, snowmelt, infiltration into frozen soils, hillslope water movement over permafrost, actual evaporation, and radiation exchange to complex surfaces have been described using physically based algorithms. The cold regions hydrological model (CRHM) platform, a flexible object‐oriented modelling system was devised to incorporate these algorithms and others and to connect them for purposes of simulating the cold regions hydrological cycle over small to medium sized basins. Landscape elements in CRHM can be linked episodically in process‐specific cascades via blowing snow transport, overland flow, organic layer subsurface flow, mineral interflow, groundwater flow, and streamflow. CRHM has a simple user interface but no provision for calibration; parameters and model structure are selected based on the understanding of the hydrological system; as such the model can be used both for prediction and for diagnosis of the adequacy of hydrological understanding. The model is described and demonstrated in basins from the semi‐arid prairie to boreal forest, mountain and muskeg regions of Canada where traditional hydrological models have great difficulty in describing hydrological phenomena. Some success is shown in simulating various elements of the hydrological cycle without calibration; this is encouraging for predicting hydrology in ungauged basins. Copyright © 2007 John Wiley & Sons, Ltd.
Modelling enhanced infiltration of snowmelt ions into frozen soil
Authors: Lilbæk Gro , Pomeroy John W.
Published: August 2007

A model is proposed in which the cumulative load of an ion infiltrating into frozen unsaturated soil can be estimated as a function of meltwater ion concentration and infiltration rate. Assumptions of the model are that the meltwater solution released to the soil surface is conservative, fully mixed within each time step, and that mass and energy are conserved. Infiltration and meltwater concentration are estimated using relationships developed by Gray and Stein respectively. The model suggests that the relationship between ion concentration and volume of infiltration is non‐linear with a positive covariance. Infiltration of snowmelt ions is therefore a function of the products of the mean concentration in the meltwater and the cumulative volume of water that infiltrates, plus the covariance between instantaneous values of ion concentration and infiltration rate. This covariance effect is termed enhanced infiltration. Meteorological observations and soil parameters from four sites in western Canada were used to assess the sensitivity of the model to conditions at a prairie site, a boreal forest site, a mountain forest site, and a shrub tundra site. Model results showed the greatest cumulative infiltration of ion load for the Prairie site; the general ranking was Prairie > Mountain Forest > Boreal Forest > Tundra. However, the greatest impact of enhanced infiltration was found for the Tundra site. At this site, enhanced infiltration caused up to 50% more ion load to infiltrate within the initial third of the melt period compared to infiltration estimates not accounting for this effect. Over the whole melt period, enhanced infiltration caused 55–160% more ion load to infiltrate than estimates based solely on the mean depth of infiltration and ion concentration. Sensitivity analysis showed that enhanced infiltration varies most strongly with initial snow water equivalent, average melt rate over the whole melt period, and snowpack ion elution concentration factor (CF). Copyright © 2007 John Wiley & Sons, Ltd.
Determining snow water equivalent by acoustic sounding
Authors: Kinar N. J. , Pomeroy J. W.
Published: August 2007

The possibility of determining snow water equivalent (SWE) by the use of an acoustic impulse was assessed at two field locations in Saskatchewan and British Columbia, Canada. These sites represent cold windswept prairie and temperate deep mountain snowcovers. A continuous frequency‐swept acoustic wave was sent into the snowpack and received. Signal processing was then subsequently used to estimate the depth and density of each snow layer by a recursive relationship involving frequency‐modulated continuous‐wave (FMCW) radar and seismological techniques. From this method, it is also shown that the tortuosity of snow can be estimated. Data collected by gravimetric sampling was used as comparison to the SWE values determined by the use of acoustic sounding. The results showed that for the Saskatchewan sites, the correlation between the measured and the modeled values of SWE was 0·86, whereas at the British Columbia sites, the correlation was 0·78. The difference in the correlations was interpreted as being due to additional acoustic measurement error at the British Columbia sites caused by higher liquid water contents and more layers in the snowpack. The measured and the modeled SWE for Saskatchewan snowpacks with high liquid water contents were found to be weakly associated with correlations of 0·30. The acoustically‐determined values of tortuosity were close to unity (α ≈ 1), which is in agreement with the values characteristic of snow as a porous substance. Further research is necessary to determine whether this technique can be applied to snow in other environmental conditions. Copyright © 2007 John Wiley & Sons, Ltd.
Field and laboratory estimates of pore size properties and hydraulic characteristics for subarctic organic soils
Authors: Carey Sean K. , Quinton William L. , Goeller Neil T.
Published: August 2007

Characterizing active and water‐conducting porosity in organic soils in both saturated and unsaturated zones is required for models of water and solute transport. There is a limitation, largely due to lack of data, on the hydraulic properties of unsaturated organic soils in permafrost regions, and in particular, the relationship between hydraulic conductivity and pressure head. Additionally, there is uncertainty as to what fraction of the matrix and what pores conduct water at different pressure heads, as closed and dead‐end pores are common features in organic soil. The objectives of this study were to determine the water‐conducting porosity of organic soils for different pore radii ranges using the method proposed by Bodhinayake et al. (2004) [Soil Sci. Soc. Am. J. 68:760–769] and compare these values to active pore size distributions from resin‐impregnated laboratory thin sections and pressure plate analysis. Field experiments and soil samples were completed in the Wolf Creek Research Basin, Yukon. Water infiltration rates were measured 16 times using a tension infiltrometer (TI) at 5 different pressure heads from − 150 to 0 mm. This data was combined with Gardiner's (1958) exponential unsaturated hydraulic conductivity function to provide water‐conducting porosity for different pore‐size ranges. Total water‐conducting porosity was 1·1 × 10−4, which accounted for only 0·01% of the total soil volume. Active pore areas obtained from 2‐D image analysis ranged from 0·45 to 0·60, declining with depth. Macropores accounted for approximately 65% of the water flux at saturation, yet all methods suggest macropores account for only a small fraction of the total porosity. Results among the methods are highly equivocal, and more research is required to reconcile field and laboratory methods of pore and hydraulic characteristics. However, this information is of significant value as organic soils in permafrost regions are poorly characterized in the literature. Copyright © 2007 John Wiley & Sons, Ltd.
Different membrane modifications revealed by atomic force/lateral force microscopy after doping of human pancreatic cells with Cd, Zn, or Pb
Authors: Girasole Marco , Cricenti Antonio , Generosi Renato , Longo Giovanni , Pompeo Giuliano , Cotesta Simona , Congiu‐Castellano Agostina
Published: August 2007

The interaction of the cytotoxic metals cadmium, zinc, and lead with pancreatic cells was studied by atomic force/lateral Force microscopy (AFM/LFM), an approach that provides both topographic (with nanometer scale lateral resolution) and chemical information on the membrane. Different morphological modifications of the overall cell shape and roughness took place as consequence of 100 μM metal‐dependent treatment. Furthermore, after exposure to Cd(Cl2) and Zn(Cl2), but not Pb(Cl2), the LFM images revealed several areas of the cell's surface showing lateral friction contrasts that have been interpreted as marker of different alterations of the cell physiology induced by the metal loading. Thus, the coupling of LFM detection to topographic AFM characterization allows to distinguish, through a nondestructive and surface characterising approach, between different metal‐induced cytotoxic effects on cells. In this framework, the role of the LFM as an important tool to discriminate between different alteration of a biological system has to be highlighted. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Characterization and expression profile of the ovarian cytochrome P‐450 aromatase (cyp19A1) gene during thermolabile sex determination in pejerrey, Odontesthes bonariensis
Authors: Karube Makiko , Fernandino Juan Ignacio , Strobl‐Mazzulla Pablo , Strüssmann Carlos Augusto , Yoshizaki Goro , Somoza Gustavo Manuel , Patiño Reynaldo
Published: August 2007

Cytochrome P450 aromatase (cyp19) is an enzyme that catalyzes the conversion of androgens to estrogens and may play a role in temperature‐dependent sex determination (TSD) of reptiles, amphibians, and fishes. In this study, the ovarian P450 aromatase form (cyp19A1) of pejerrey Odontesthes bonariensis, a teleost with marked TSD, was cloned and its expression profile evaluated during gonadal differentiation at feminizing (17°C, 100% females), mixed‐sex producing (24 and 25°C, 73.3 and 26.7% females, respectively), and masculinizing (29°C, 0% females) temperatures. The deduced cyp19A1 amino acid sequence shared high identity (>77.8%) with that from other teleosts but had low identity (<61.8%) with brain forms (cyp19A2), including that of pejerrey itself. The tissue distribution analysis of cyp19A1 mRNA in adult fish revealed high expression in the ovary. Semi‐quantitative reverse transcription polymerase chain reaction analysis of the bodies of larvae revealed that cyp19A1 expression increased before the appearance of the first histological signs of ovarian differentiation at the feminizing temperature but remained low at the masculinizing temperature. The expression levels at mixed‐sex producing temperatures were bimodal rather than intermediate, showing low and high modal values similar to those at the feminizing and masculinizing temperatures, respectively. The population percentages of high and low expression levels at intermediate temperatures were proportional to the percentage of females and males, respectively, and high levels were first observed at about the time of sex differentiation of females. These results suggest that cyp19A1 is involved in the process of ovarian formation and possibly also in the TSD of pejerrey. J. Exp. Zool. 307A:625–636, 2007. © 2007 Wiley‐Liss, Inc.
Eye drop delivery of nano‐polymeric micelle formulated genes with cornea‐specific promoters
Authors: Tong Yaw‐Chong , Chang Shwu‐Fen , Liu Chia‐Yang , Kao Winston W.‐Y. , Huang Chong Heng , Liaw Jiahorng
Published: August 2007

Background

This study evaluates the eye drop delivery of genes with cornea‐specific promoters, i.e., keratin 12 (K12) and keratocan (Kera3.2) promoters, by non‐ionic poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) (PEO‐PPO‐PEO) polymeric micelles (PM) to mouse and rabbit eyes, and investigates the underlying mechanisms.

Methods

Three PM‐formulated plasmids (pCMV‐Lac Z, pK12‐Lac Z and pKera3.2‐Lac Z) containing the Lac Z gene for β‐galactosidase (β‐Gal) whose expression was driven by the promoter of either the cytomegalovirus early gene, the keratin 12 gene or the keratocan gene, were characterized by critical micelle concentration (CMC), dynamic light scattering (DLS), and atomic force microscopy (AFM). Transgene expression in ocular tissue after gene delivery was analyzed by 5‐bromo‐4‐chloro‐3‐indolyl‐β‐D‐galactoside (X‐Gal) color staining, 1,2‐dioxetane β‐Gal enzymatic activity measurement, and real‐time polymerase chain reaction (PCR) analysis. The delivery mechanisms of plasmid‐PM on mouse and rabbit corneas were evaluated by EDTA and RGD (arginine‐glycine‐aspartic acid) peptide.

Results

The sizes of the three plasmid‐PM complexes were around 150–200 nm with unimodal distribution. Enhanced stability was found for three plasmid‐PM formulations after DNase I treatment. After six doses of eye drop delivery of pK12‐Lac Z‐PM three times a day, β‐Gal activity was significantly increased in both mouse and rabbit corneas. Stroma‐specific Lac Z expression was only found in pKera3.2‐Lac Z‐PM‐treated animals with pretreatment by 5 mM EDTA, an opener of junctions. Lac Z gene expression in both pK12‐Lac Z‐PM and pKera3.2‐Lac Z‐PM delivery groups was decreased by RGD peptide pretreatment.

Conclusions

Cornea epithelium‐ and stroma‐specific gene expression could be achieved using cornea‐specific promoters of keratin 12 and keratocan genes, and the gene was delivered with PM formulation through non‐invasive, eye drop in mice and rabbits. The transfection mechanism of plasmid‐PM may involve endocytosis and particle size dependent paracellular transport. Copyright © 2007 John Wiley & Sons, Ltd.
Investigating the presence of pesticide transformation products in water by using liquid chromatography‐mass spectrometry with different mass analyzers
Authors: Hernández Félix , Ibáñez María , Pozo Óscar J. , Sancho Juan V.
Published: August 2007

Many pesticide transformation products (TPs) can reach environmental waters as a consequence of their normally having a higher polarity than their parent pesticides. This makes the development of analytical methodology for reliable identification and subsequent quantification at the sub‐microgram per liter levels necessary, as required under current legislation. In this paper we report the photodegradation of several pesticides frequently detected in environmental waters from the Spanish Mediterranean region using the high‐resolution and exact‐mass capabilities of hybrid quadrupole time‐of‐flight mass spectrometry (QTOF MS) hyphenated to liquid chromatography (LC). Once the main photodegradation/hydrolysis products formed in aqueous media were identified, analytical methodology for their simultaneous quantification and reliable identification in real water samples was developed using on‐line solid‐phase extraction (SPE)‐LC‐tandem MS with a triple‐quadrupole (QqQ) analyzer. The methodology was validated in both ground and surface water samples spiked at the limit of quantification (LOQ) and 10 × LOQ levels, i.e. 50 and 500 ng/l, obtaining satisfactory recoveries and precision for all compounds. Subsequent analysis of ground and surface water samples resulted in the detection of a number of TPs higher than parent pesticides. Additionally, several soil‐interstitial water samples collected from the unsaturated zone were analyzed to explore the degradation/transformation of some pesticides in the field using experimental plots equipped with lisimeters. Several TPs were found in these samples, with most of them having also been detected in ground and surface water from the same area. This paper illustrates the extraordinary potential of LC‐MS(/MS) with QTOF and QqQ analyzers for qualitative/structural and quantitative analysis, respectively, offering analytical chemists one of the most powerful tools available at present to investigate the presence of pesticide TPs in water. Copyright © 2007 John Wiley & Sons, Ltd.
Assessments of Mediterranean precipitation changes for the 21st century using statistical downscaling techniques
Authors: Hertig E. , Jacobeit J.
Published: August 2007

Statistical downscaling techniques are used to assess Mediterranean precipitation changes for the period 1990–2100 under increased greenhouse warming conditions from climate model output of large‐scale predictor changes. Analyses are carried out on a monthly basis for the main rainy season from October to May. Results of two statistical techniques, multiple regression analysis, and canonical correlation analysis, are compared. Furthermore, differences which arise from the use of different combinations of the predictor variables, such as geopotential heights, humidity, and sea surface temperatures are discussed. Predictor output from seven different AOGCM runs (two ECHAM4/OPYC3 runs, four ECHO‐G runs including a three‐member ensemble, and one HadCM3 run) is used to assess Mediterranean precipitation changes in the 21st century. Five of the AOGCM runs were forced with B2 scenario assumptions according to the special report on emission scenarios (SRES), one with SRES‐A2 scenario assumptions, and one with the former IS92a scenario. Using 1000 hPa‐/500 hPa‐geopotential heights and 1000 hPa‐specific humidity as large‐scale predictors, a shorter but wetter wet season is evident for the western and northern Mediterranean regions including precipitation increases in winter and decreases in the transitional seasons for the period 2071–2100 compared to 1990–2019. The eastern and southern parts of the Mediterranean area exhibit mainly negative precipitation changes from October to May for an increased greenhouse gas forcing. Copyright © 2007 Royal Meteorological Society
Targeting gold at the end of the rainbow: Surgical gamma probes in the 21st century
Authors: Moffat Frederick L.
Published: August 2007

Surgical gamma detection probes (GDPs) have become important in the surgical management of neoplastic disease in the past 20 years. Their history and radiophysics are discussed, with consideration of the overarching issue of tumor‐to‐background ratio (TBR). GDPs are currently most commonly used in sentinel node applications in a variety of tumors. Whether their role in clinical surgical practice can be extended to other applications will depend on the development of radiolabeled tumor marking agents which have much improved TBR, and parallel developments in oncology research which may overtake this technology. J. Surg. Oncol. 2007;96:286–289. © 2007 Wiley‐Liss, Inc.
PET probe‐guided surgery
Authors: Gulec Seza A.
Published: August 2007

Intraoperative localization of PET‐positive recurrent/metastatic lesions can be facilitated using a hand‐held PET probe. PET probe is a high‐energy gamma probe designed to process the 511 keV photons of PET tracers. Intraoperative gamma probe performance is a function of radiopharmaceutical uptake, clearance kinetics, and probe engineering, all determining the target to background ratio (TBR) and detection threshold. A minimum TBR of 1.5:1 is needed in the operative field for the operating surgeon to be comfortable the differences between tumor tissue and normal adjacent tissue are real. Due to high‐energy photon fluxes, achieving a satisfactory TBR intraoperatively is challenging and requires development of a clinically feasible PET‐probe guided surgery protocol. J. Surg. Oncol. 2007;96:353–357. © 2007 Wiley‐Liss, Inc.
The sentinel concept in patients with cervical cancer
Authors: Schneider Achim
Published: August 2007

The sentinel concept for patients with early cervical cancer has a high potential for decreasing morbidity and for increasing oncologic safety. The detection rate with technetium‐labeling or a combination with blue dye varies between 84% and 92%. Sensitivity and negative predictive value depend on tumor size: the smaller the tumor, the higher the validity of the technique. Detection of circulating tumor cells in the sentinel node using HPVmRNA as marker may have a good prognostic value. Currently the sentinel concept should only be used in clinical studies before its validity has been proved. J. Surg. Oncol. 2007;96:337–341. © 2007 Wiley‐Liss, Inc.
Macromol. Chem. Phys. 17/2007
Authors: Kang Hyo , Kwon Ki‐Sun , Kang Daeseung , Lee Jong‐Chan
Published: August 2007

Cover: The picture depicts the orientation behavior of liquid crystals on rubbed and unrubbed polymer surfaces (AFM images). Before rubbing, the polymer surface shows no groves and the direction of liquid crystals is random, while after rubbing groves on the polymer surfaces appear and the liquid crystals orients perpendicular to the grove direction (or rubbing direction). Further details can be found in the Full Paper by H. Kang, K.‐S. Kwon, D. Kang, and J.‐C. Lee* on page 1853.
Influence of Low‐Molecular‐Weight Diamines in the Direct Imidation of Poly(propylene)‐Grafted Maleic Anhydride by Melt Reaction
Authors: Vazquez‐Rodriguez Sofia , Sánchez‐Valdes Saúl , Rodríguez‐González Francisco J. , González‐Cantú Maria C.
Published: August 2007

Aminated poly(propylene) was prepared by reacting aliphatic primary diamines with maleic‐anhydride‐functionalized poly(propylene) by in situ melt reaction. Around 60–70% of the initial acid groups had reacted to form amide and imide groups as confirmed by the almost complete disappearance of the maleic anhydride peak in FT‐IR spectra. The molecular weight of the diamines had an influence on changes in molecular structure of the PP‐g‐NH2 as a result of secondary reactions such as chain extension and cross‐linking. PP‐g‐NH2 and polycarbonate were pressed into two‐layer films and their adhesion strength was measured. The results showed that PP‐g‐NH2 was a very effective adhesion promoter.

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Mechanical and Morphological Studies of Poly(propylene)‐Filled Eggshell Composites
Authors: Toro Patricio , Quijada Raúl , Arias José Luis , Yazdani‐Pedram Mehrdad
Published: August 2007

Poly(propylene) (PP) composites were prepared by using eggshell (ES) as filler and their mechanical properties were compared with those using talc (TA) and calcium carbonate (CC) of different grain sizes (X50). A decrease in impact strength and deformation at break with increase in filler content was observed. The PP composite with ES (X50 = 8.4 µm) was stiffer than those with CC (X50 = 0.7 µm). The hybrid composite PP‐ES‐TA showed a similar stiffness as the PP‐TA composites due to the similar morphology of TA (X50 = 0.5 µm) and ES, when TA was replaced up to 75 wt.‐% by ES. SEM study revealed evidence of improved interfacial bonding between PP and ES in theirs composites.

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Customer retention when the customer's future usage is uncertain
Authors: White Tiffany Barnett , Lemon Katherine N. , Hogan John E.
Published: August 2007

Consumers are often uncertain about how much they will use a service in the future (e.g., health clubs, credit cards, cell phones), yet the effects of this uncertainty on customer retention have not been studied. This research investigates factors influencing consumers' decisions about whether to retain noncontractual services for which anticipated future usage levels are uncertain. The studies show that Future Usage Uncertainty (FUU) generally reduces the likelihood that a customer will continue in a service relationship. However, when consumers consider the flexibility they have to delay the keep/drop decision (i.e., drop flexibility), or the anticipated regret associated with making the wrong decision, the effects of FUU are essentially eliminated, and consumers are more likely to continue in the relationship. © 2007 Wiley Periodicals, Inc.
Gratitude, delight, or guilt: The role of consumers' emotions in predicting postconsumption behaviors
Authors: Soscia Isabella
Published: August 2007

This study investigates the relationships among appraisals (goal congruence/incongruence and agency), consumption emotions (gratitude, happiness, guilt, anger, pride, and sadness), and post‐consumption behaviors (positive and negative word of mouth, repurchase intention, and complaint behavior). The findings demonstrate that these emotions predict different specific types of post‐consumption behaviors and that they are elicited by appraisals specified in the psychology literature. In particular, gratitude but not happiness, predicts repurchase intention and positive word of mouth. By contrast, guilt inhibits complaint behaviors and negative word of mouth. The implications of these findings for marketing practice are discussed. © 2007 Wiley Periodicals, Inc.
Stereospecific and Stereoselective Polymerization of 4‐Methyl‐1‐hexene by Enantiomeric Binaphthyl‐Bridged Salen Dichlorozirconium (IV) Complexes
Authors: Strianese Maria , Lamberti Marina , Mazzeo Mina , Pellecchia Claudio
Published: August 2007

Two enantiomers of a chiral binaphthyl‐bridged salen dichlorozirconium (IV) complex (namely R‐Λ‐1 and S‐Δ‐1) were synthesized and tested as pre‐catalysts for 4‐methyl‐1‐hexene (4MH) polymerization. Their behavior was compared with that of the same complex in its racemic form. Isotactic poly(4‐methyl‐1‐hexene) was produced in both cases, but the polymerization of racemic 4MH promoted by the optically active catalysts preferentially consumed one antipode, showing some stereoselectivity for the process.

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Modelling the urban climate using a local governmental geo‐database
Authors: Lindberg Fredrik
Published: August 2007

In this study, local government digital spatial data are used to describe urban geometry and analyse spatial variations of the urban climate within the central areas of Göteborg, Sweden. A high‐resolution raster digital elevation model (1 m pixel resolution) consisting of building structures and ground heights is derived from a local government geo‐database, as well as land use patterns and artificial heat sources. Parameters such as the sky view factor (SVF) and daily averages of solar radiation are calculated. Results obtained from the model are compared with intra‐urban air temperature variations which are derived from mobile measurements, as well as surface temperature variations derived from thermal infrared images. Results show that high‐resolution digital elevation models in raster format are very useful sources of data for the investigation of intra‐urban temperature variations. Results also show that the areal mean of SVF correlates with intra‐urban air temperature variations to a higher degree than SVF that is taken from a point source location. The correlation between the modelled SVF and surface temperature is high during both spring and winter. Adding information about daily averages of global radiation for the spring measurement causes the correlation between SVF and surface temperature variations to increase. Copyright © 2007 Royal Meteorological Society
Statistical quality control for local‐scale extreme temperatures. Case study: Lisbon, Portugal
Authors: Lucio P. S. , Serrano A. I. , Deus R. J. R.
Published: August 2007

One of the biggest constraints to the study of meteorological fields is the fact that ground‐based meteorological networks do not operate over a common period of adequate length. In general, the biggest drawback is that recorded data must be gap‐filled and quality controlled (coherent, consistent and homogeneous) to provide a reliable, continuous, reference daily/monthly/yearly series. This paper addresses procedures for statistical quality control of extremes of air temperature (daily maximum and minimum) time series. The diagnostic was accomplished based on the analysis of daily time series (1941–1996), monthly time series (1941–2001) and yearly time series (1941–2001) from 18 meteorological stations located in the Lisbon (Portugal) metropolitan region. To obtain insight into the quality of the series of the temperature data, objective statistical tests for departure from homogeneity were applied to the time series. To illustrate the procedures, one assesses the homogeneity of the reconstructed time series to check the quality of the ‘virtual’ observations and some tests were run over the annual, seasonal and monthly series of extreme temperatures. None of these assessments was able to detect a spatial non‐homogeneity in the temperature series around the tested years. As expected, the optimal interpolation approach for time series reconstruction, proposed by Lucio and Deus (2005), seems to be robust, considering a wide range of methods to test homogeneity of the reconstructed time series. Afterwards, one can apply the reconstituted monthly series of extreme air temperature anomalies, for each meteorological station, to analyse the respective trends, when they exist. Copyright © 2007 Royal Meteorological Society
Mesoscale simulation of an extreme rainfall event over Mumbai, India, using a high‐resolution MM5 model
Authors: Litta A. J. , Chakrapani B. , Mohankumar K.
Published: August 2007

Mesoscale models are essential for the accurate prediction of high‐impact weather, such as severe thunderstorms, heavy rainfall events, mountain weather forecasting, cloudbursts and cyclones. An attempt has been made in the present study to simulate the heavy rainfall event that occurred during 26 July 2005 over Santa Cruz (19.20°N, 72.53°E) in Mumbai, India, using the Fifth‐Generation NCAR/Penn State Mesoscale Model (MM5). The cloud‐resolving mesoscale model with the right combination of the nesting domains, horizontal resolution and cloud parameterization schemes, is able to simulate the heavy rainfall event both qualitatively and quantitatively. The model results indicate the existence of an intense mesoscale vortex in the mid‐troposphere during this heavy rainfall event. The localized heavy rainfall which occurred over Santa Cruz may possibly be due to the subsidence of the mid‐tropospheric mesoscale vortex, superimposed on the active monsoon conditions over this region. Copyright © 2007 Royal Meteorological Society
Geographical distribution of road slipperiness in Sweden, on national, regional and county scales
Authors: Andersson A. K. , Gustavsson T. , Bogren J. , Holmer B.
Published: August 2007

The influence of latitude on the distribution of slipperiness of roads in Sweden was studied at three scales: national, regional and county. Data from 654 Road Weather Information System (RWIS) stations were compiled over five winter seasons, from 1998/1999 to 2002/2003. The aim of the study was to establish a basis on which to model how future climate changes might affect frequency of slipperiness and costs for maintenance in winter. Four types of slipperiness were studied (slippery conditions due to moderate (HR1) or severe (HR2) hoarfrost, moist/wet surface that freezes (HT), and rain or sleet falling on a cold road (HN)), all adding up to form the winter index (WI).

In Sweden, the distribution of slipperiness varies depending on the scale (national, regional or county). On the national and regional scales the mean temperatures give a general picture of the total slipperiness—i.e. dependence on latitude; different factors were tested and latitude proved to be the most correlated. Slipperiness caused by HR1 and HR2 hoarfrost tends to increase towards the north, while road icing (HT) decreases. On the county scale, neither latitude nor any other tested geographical variable, could explain much of the variance. Local climate and the directions of movement of individual weather systems may be more important. The regional scale is considered to be most suitable for future modelling of the influence of the effect of a changed climate on the slipperiness of the roads. Copyright © 2007 Royal Meteorological Society
An exploration of the NHS end of life care programme and its potential use for patients with end‐stage systemic sclerosis
Authors: Reay Naomi
Published: August 2007

Systemic sclerosis is an autoimmune connective tissue disorder with the highest case‐specific mortality of the rheumatic disorders (Denton and Black, 1999). Despite recent developments in the treatment of systemic sclerosis, patients are still dying from its complications. Therefore the palliative care needs of patients with end‐stage systemic sclerosis must be considered. There is little research into palliative care for patients with systemic sclerosis, but clinical experience suggests the level of care has been dependent upon local resources and the experience of the team responsible for the patient's care. The need for equitable, high‐quality palliative care for patients with end‐stage systemic sclerosis may be met by current developments in end of life care within the UK. The present paper outlines the NHS end of life care programme (DoH, 2003; NICE, 2003) and uses a case study approach to illustrate its application to palliative care in end‐stage systemic sclerosis. Copyright © 2007 John Wiley & Sons, Ltd.
Assessment of clinical nurse specialists in rheumatology using an OSCE
Authors: Ryan Sarah , Stevenson Kay , Hassell Andrew B
Published: August 2007

Objective: To introduce a new method of assessment; an observed structured clinical examination (OSCE) into a postgraduate course for rheumatology clinical nurse specialists.

Method: The OSCE was introduced into a physical assessment module, which focused on the nurses' ability to perform an examination of patients' shoulders, knees and hands. A modified blueprinting exercise was used to ensure adequate sampling of the different components of the syllabus. This resulted in five active stations and one rest station. The active stations included history‐taking, physical examination of the shoulder, knee and hand complexes and multidisciplinary management plans. To enhance authenticity real, rather than simulated, patients were used where practical.

Results: All 11 students passed all stations, the lowest score related to history‐taking and the highest score related to devising a management plan. All 11 students rated the OSCE a worthwhile experience reflecting the learning outcomes of the module and recommended that the OSCE should be used to assess the next cohort of students. Eight students found the OSCE too ‘anxiety‐provoking’ and did not want this method of assessment to be used in other modules. All examiners felt this mode of assessment was more valid than the previous assessment format of a viva on a single patient.

Conclusion: This was the first time an OSCE was used in a postgraduate course to assess the physical examination skills of rheumatology nurse specialists. The course faculty, examiners and students found it was a reliable and valid means of assessment. Copyright © 2007 John Wiley & Sons, Ltd.
Treatment choices, preferences and decision‐making by patients with rheumatoid arthritis
Authors: Chilton Frances , Collett Raymond A.
Published: August 2007

Objectives: To explore rheumatoid arthritis (RA) patient treatment preferences, their decision‐making and the treatment choices they would make when faced with three anti‐tumour necrosis factor‐α (TNF‐α) therapy options.

Methods: Two methods of enquiry were used: postal questionnaire and one‐to‐one interviews. RA patients not taking anti‐TNF‐α medications were asked to complete a questionnaire after reading a written scenario, which involved choosing and identifying factors that influenced their treatment choice from three anti‐TNF‐α therapies: etanercept (Enbrel), adalimumab (Humira) and infliximab (Remicade). Patients who had tried more than one anti‐TNF‐α medication were asked at one‐to‐one interviews for their treatment preferences and how their current treatment had been decided.

Results: Both interviewees and questionnaire respondents chose adalimumab as their preferred treatment. Interviewees identified lack of control, convenience and technical issues as influencing treatment choice. Questionnaire respondents were less likely than interviewees to want to participate in making decisions about the selection of anti‐TNF‐α therapy. There were few gender differences. Patients younger than 61 years old were more confident about self‐administering treatment, and preferred subcutaneous (sc) over intravenous (iv) medication, as this reduced regular hospital attendance. Older patients preferred health care staff to administer treatment and more readily identified ‘contact with other patients/meeting others’ and ‘staff availability if problems arise’ as factors influencing choice.

Conclusions: RA patients demonstrate a clear treatment preference. Different factors influence patients who choose sc compared with iv medications. Many RA patients either wished to share in treatment decisions or relinquish responsibility to the health professional when choosing anti‐TNF‐α therapy. Patients require reassurance and continuing dialogue with clinicians to manage their condition optimally. Copyright © 2007 John Wiley & Sons, Ltd.