bluuebunny/crossref_metadata_2025 huggingface dataset:
The relation of anger to disgust: the potential role of coupled emotions within eating pathology
Authors: Fox John R. E. , Harrison Amy
Published: April 2008

Objective: difficulties with anger and disgust have been highlighted within females with eating pathology (FEP). However, research has not investigated whether FEP experience greater levels of anger compared to controls or how these two emotions may interact in FEP. It was predicted that FEP would show significantly higher levels of state anger and this would also lead to a significant increase in disgust for FEP. Method: the experimental group (n = 25) had significant levels of eating pathology. Data from the State‐Trait Anger Expression Inventory‐2 and a disgust measure was collected before and after the induction of an angry state. Results: the bulimic group, in comparison to normal controls, demonstrated a significant increase in the state anger scores at time 2 and on the Disgust Sensitivity Scale. Conclusion: the findings demonstrate that the emotions of anger and disgust may be ‘coupled’, and disgust may be used to manage the ‘egodystonic’ emotion of anger in people with eating pathology. Copyright © 2008 John Wiley & Sons, Ltd.
Compassionate mind training with people who hear malevolent voices: a case series report
Authors: Mayhew Sophie L. , Gilbert Paul
Published: April 2008

This paper presents a series of case studies to explore the understanding, acceptance and value of compassionate mind training (CMT) with psychotic voice hearers. We were interested in the degree to which such people are able to access and feel the positive emotions of ‘warmth’ and ‘contentment’ to become more self‐compassionate. We also explored how CMT affected participants' hostile voices, their levels of anxiety, depression, paranoia and self‐criticism. Participants were invited to offer suggestions for tailoring this approach for voice hearers. Results showed decreases for all participants in depression, psychoticism, anxiety, paranoia, Obsessive–Compulsive Disorder and interpersonal sensitivity. All participants' auditory hallucinations became less malevolent, less persecuting and more reassuring. Copyright © 2008 John Wiley & Sons, Ltd.
Carbohydrates as Building Blocks of Privileged Ligands for Multiphasic Asymmetric Catalysis
Authors: Benessere Vincenzo , De Roma Antonella , Ruffo Francesco
Published: April 2008

To combine the high chemical performance of asymmetric catalysis with the increasing need for sustainability, a strategy is presented that involves the straightforward preparation of “Trost”‐like ligands suitable for application in multiphasic homogeneous catalysis. Ligands with coordinating functions (phosphinoamide‐phoshinoester groups) as well as phase tags introduced on a D‐glucose scaffold were prepared and then examined in the Pd‐catalysed asymmetric desymmetrization of meso‐2‐cyclopenten‐1,4‐diol biscarbamate. In line with our assumption, the performance of the catalyst system under traditional conditions is as high as that of the original Trost ligand, derived from trans‐cyclohexanediamine, giving enantioselectivities of 98 % ee. Moreover, promising results were observed under multiphasic homogeneous conditions.
Effective clearance of intracellular Leishmania majorin vivo requires Pten in macrophages
Authors: Kuroda Shoko , Nishio Miki , Sasaki Takehiko , Horie Yasuo , Kawahara Koichi , Sasaki Masato , Natsui Miyuki , Matozaki Takashi , Tezuka Hiroyuki , Ohteki Toshiaki , Förster Irmgard , Mak Tak W. , Nakano Toru , Suzuki Akira
Published: April 2008

Leishmaniases are a major international public health problem, and macrophages are crucial for host resistance to this parasite. To determine if phosphatase and tensin homologue deleted on chromosome ten (Pten), a negative regulator of the PI3K pathway, plays a role in macrophage‐mediated resistance to Leishmania, we generated C57BL/6 mice lacking Pten specifically in macrophages (LysMCrePtenflox/flox mice). Examination of lesions resulting from Leishmania major infection showed that LysMCrePtenflox/flox mice were more susceptible to the parasite than wild‐type (WT) mice in the early phase of the infection, but were eventually able to eliminate the pathogen. In vitro Pten‐deficient macrophages showed a reduced ability to kill parasites in response to IFN‐γ treatment, possibly because the mutant cells exhibited decreased TNF secretion that correlated with reductions in inducible nitric oxide synthase expression and nitric oxide production. In response to various TLR ligands, Pten‐deficient macrophages produced less TNF and IL‐12 but more IL‐10 than WT cells. However, analysis of cells in the lymph nodes draining L. major inoculation sites indicated that both LysMCrePtenflox/flox and WT mice developed normal Th1 responses following L. major infection, in line with the ability of LysMCrePtenflox/flox mice to eventually eliminate the parasite. Our results indicate that the efficient clearance of intracellular parasites requires Pten in macrophages.
Simultaneous presentation and cross‐presentation of immune‐stimulating complex‐associated cognate antigen by antigen‐specific B cells
Authors: Robson Neil C. , Donachie Anne M. , Mowat Allan McI.
Published: April 2008

We demonstrate that uptake of oligomeric cognate antigen (OVA‐hen egg lysozyme, OVA‐HEL) alone or incorporated in immune‐stimulating complexes (ISCOMS) facilitates presentation and simultaneous cross‐presentation of OVA by HEL‐specific B cells in vitro. HEL‐specific B cells stimulated CD8+ T cell responses in vitro to the same extent as bone marrow‐derived dendritic cells. Cross‐presentation by specific B cells required endosomal acidification, proteasomal processing and classical MHC class I/peptide transport. Specific B cells also acquired both antigens rapidly in vivo and presented them to CD4+ T cells. However, only HEL‐specific B cells from OVA‐HEL ISCOMS‐immunised mice could cross‐present OVA to naive OVA‐specific CD8+ T cells. Antigen‐specific B cells were also activated selectively by OVA‐HEL ISCOMS in vitro and importantly, the presence of HEL‐specific B cells promoted the persistence of clonal expansion of OVA‐specific CD8+ T cells after in vivo immunisation with OVA‐HEL ISCOMS. These results demonstrate preferential MHC class I and class II processing of cognate antigen incorporated in ISCOMS by specific B cells in vitro and in vivo, highlighting the ability of ISCOMS to target B cells and offering novel insights into the role of B cells in cross‐presentation to CD8+ T cells.
Antigen structure influences helper T‐cell epitope dominance in the human immune response to HIV envelope glycoprotein gp120
Authors: Mirano‐Bascos Denise , Tary‐Lehmann Magdalena , Landry Samuel J.
Published: April 2008

The development of an effective vaccine against HIV/AIDS has been hampered, in part, by a poor understanding of the rules governing helper T‐cell epitope immunodominance. Studies in mice have shown that antigen structure modulates epitope immunodominance by affecting the processing and subsequent presentation of helper T‐cell epitopes. Previous epitope mapping studies showed that the immunodominant helper T‐cell epitopes in mice immunized with gp120 were found flanking flexible loops of the protein. In this report, we show that helper T‐cell epitopes against gp120 in humans infected with HIV are also found flanking flexible loops. Immunodominant epitopes were found to be located primarily in the outer domain, an average of 12 residues C‐terminal to flexible loops. In the less immunogenic inner domain, epitopes were found an average of five residues N‐terminal to conserved regions of the protein, once again placing the epitopes C‐terminal to flexible loops. These results show that antigen structure plays a significant role in the shaping of the helper T‐cell response against HIV gp120 in humans. This relationship between antigen structure and helper T‐cell epitope immunodominance may prove to be useful in the development of rationally designed vaccines against pathogens such as HIV.
Acetylenetitanium Complex Stabilized by Aminopyridinato Ligands
Authors: Noor Awal , Kempe Rhett
Published: April 2008

The first acetylenetitanium complex stabilized by aminopyridinato ligands has been prepared by the reaction of Ap2TiCl2 (1) – Ap‐H = 2‐[(2,6‐diisopropylphenyl)amino]pyridine – with equimolar amount of bis(trimethylsilyl)acetylene in the presence of magnesium. The complex was characterized by spectroscopic methods as well as by X‐ray single crystal structure analysis. Reduction of 1 with KC8 under N2 in the absence of any other stabilizing ligand leads to the ligand rearrangement product Ap3Ti. In the reaction of the acetylenetitanium complex with acetone the titanaoxacyclopentene was formed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Dual Supermesityl Stabilization: A Room‐Temperature‐Stable 1,2,4‐Triphosphole Radical, Sigmatropic Hydrogen Rearrangements, and Tetraphospholide Anion
Authors: Ionkin Alex S. , Marshall William J. , Fish Brian M. , Marchione Alexander A. , Howe Laurie A. , Davidson Fredric , McEwen Charles N.
Published: April 2008

Cesium 3,5‐bis(2,4,6‐tri‐tert‐butylphenyl)‐1,2,4‐triphospholide (12) and cesium 5‐(2,4,6‐tri‐tert‐butylphenyl)tetraphospholide (13) were synthesized and isolated with flat five‐membered rings, which are an indication of the aromaticity in these anions. Compound 13 is the first example of a stable tetraphospholide anion, which is structurally characterized. Kinetic stabilization of the 1,2,4‐triphospholide system by two supermesityl groups resulted in the detection of the room‐temperature‐stable radical 17 and the observation of a series of successive sigmatropic hydrogen shifts in the first stable 1H‐1,2,4‐triphosphole 14 with a P–H bond.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis of Enantiopure Highly Functionalized Pyrrolizines and Indolizines from Natural α‐Amino Acids: An Ex­perimental and Theoretical Investigation
Authors: Borsini Elena , Broggini Gianluigi , Contini Alessandro , Zecchi Gaetano
Published: April 2008

Variously substituted enantiopure 2‐benzylamino‐1‐hydroxymethyl‐2,3‐dihydro‐1H‐pyrrolizines and 6‐benzylamino‐5,6,7,8‐tetrahydroindolizin‐8‐ols have been prepared. The reaction sequence starts from L‐α‐amino acids and involves an intramolecular cycloaddition of pyrrole‐based nitrone intermediates. A theoretical investigation at the HCTH/6‐311+G(d,p)//HCTH/6‐31+G(d) level of theory was performed with the aim of rationalizing the effects of substituents on the regiochemistry of the cycloaddition reaction.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
A First Case of Asymmetric Catalysis Induced by Metal‐Free Bisoxazolines
Authors: Akalay Deniz , Dürner Gerd , Göbel Michael W.
Published: April 2008

Metal‐free bisoxazolines catalyze the Diels–Alder reaction of N‐substituted maleimides with anthrone derivatives leading to products in excellent yields and enantioselectivities up to 70 %. A mechanism relying on Brønsted‐base catalysis is assumed to be involved with formation of an ion pair between the protonated catalyst and the anthrone enolate, which acts as a diene.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Reaction Pattern in Vertebrate Cells (RiV): May the anti‐RiV ELISA Detect a Pathologic Cell Proliferation? (First Results)
Authors: Liebermann H. E. H.
Published: April 2008

RiV is mainly represented by characteristic exosome‐like particles with a diameter of 30 to 70 nm. RiV particle preparations (RiV‐PP) contain identified proteins. In the present paper, the authors started an evaluation of the hypothesis, that RiV‐reactive antibodies, detected in patient sera by an indirect ELISA, may be used for the diagnosis of pathologic cell proliferations. On the basis of the frequency distribution curve of about 500 blood donor sera, cut‐off values for RiV‐reactive IgG and IgM antibodies could be defined. Additionally it was found that 1.6 % of blood donor sera reacted strongly with an RiV‐PP (of calf kidney cells) for IgG antibodies. 29 % of cancer patient sera (n = 48), 17 % of 53 patients with endoprothetics and with lung disorders, 44.3 % of 115 patient sera of a doctor's practice and 28 % of 97 sera of 10 to 11 years old schoolchildren were positive in the anti‐RiV ELISA with IgG antibodies. About half of the selected group of schoolchildren contained different autoantibodies and some of these children displayed already insulin dependent diabetes mellitus (as shown by others). A correlation of our ELISA results with the other autoimmune antibody results was not found. Using RiV‐PP as an antigen complex, isolated from calf kidney cell cultures or from human FL cell cultures and HeLa cell cultures, results with small differences between human and animal RiV origin were obtained. Using the human RiV, the number of positive sera was not significantly lower. Generally, the anti‐RiV ELISA, using RiV‐PP from human cell cultures, detect autoantibodies against RiV‐specific proteins. This assay may detect, but not diagnose pathologic cell proliferation. The possibilities of RiV ELISA for diagnostics of defined autoimmune diseases, as well as further studies and the more meaningful RiV immunoblot are discussed.
The two‐user Gaussian interference channel: a deterministic view
Authors: Bresler Guy , Tse David
Published: April 2008

This paper explores the two‐user Gaussian interference channel through the lens of a natural deterministic channel model. The main result is that the deterministic channel uniformly approximates the Gaussian channel, the capacity regions differing by a universal constant. The problem of finding the capacity of the Gaussian channel to within a constant error is therefore reduced to that of finding the capacity of the far simpler deterministic channel. Thus, the paper provides an alternative derivation of the recent constant gap capacity characterisation of Etkin, Tse and Wang. Additionally, the deterministic model gives significant insight towards the Gaussian channel. Copyright © 2008 John Wiley & Sons, Ltd.
Olfactory properties of straight‐chain undecan‐x‐ones, undecan‐x‐ols (x = 2–6) and their derivatives
Authors: Gibka Julia , Gliński Marek
Published: April 2008

A series of undecan‐x‐ones (x = 2–6) was used as starting material in the synthesis of ethylene and propylene acetals, undecanols and their acetates. Undec‐3‐yl and undec‐6‐yl acetates, ethylene acetal of undecan‐3‐one and propylene acetals of undecan‐x‐ones (x = 2–5) have not yet been described. The odour properties for all the synthesized compounds have been determined. They have pleasant, fruity, herbaceous odours that can be described as food odours. The most valuable groups of compounds are ketones and their acetals, which have intense, pleasant, fruity, vegetable, spicy or herbaceous odours. In the case of alcohols, mild odours dominate with fruity, wooden or floral notes. All acetates have faint or mild fatty‐soapy odours. A correlation between the structure of the studied compounds and their odours has been found. Fruity odours appear among ketones and alcohols when a shift of the functional group from position 2 to the middle of the molecule occurs. In the studied ethylene and propylene acetals this shift strengthens their vegetable and spicy odours, respectively. Copyright © 2008 John Wiley & Sons, Ltd.
Essential oil variability in Baccharis uncinella DC and Baccharis dracunculifolia DC growing wild in southern Brazil, Bolivia and Uruguay
Authors: Frizzo Caren D. , Atti‐Serafini Luciana , Laguna Sergio Echeverrigaray , Cassel Eduardo , Lorenzo Daniel , Dellacassa Eduardo
Published: April 2008

Essential oils of Baccharis uncinella DC and B. dracunculifolia DC collected from different wild populations growing in Bolivia, southern Brazil and Uruguay were analysed using gas chromatography and gas chromatography–mass spectrometry techniques, to check for chemical variability. Cluster analysis led to the identification of two chemotypes for B. dracunculifolia, related to aromadendrane‐ or cadinane‐derived components. As the timing of sampling of the plant material may have an influence on the composition of the essential oil isolated, the seasonal influence at the moment of harvesting was studied for two populations of each species. The results suggested that the flowering season was optimal both species and this supported the practice of harvesting at the full bloom stage. Copyright © 2008 John Wiley & Sons, Ltd.
Chemical composition and antibacterial activity of the essential oil from Mentha suaveolens ssp. insularis (Req.) Greuter
Authors: Sutour Sylvain , Bradesi Pascale , de Rocca‐Serra Dominique , Casanova Joseph , Tomi Félix
Published: April 2008

A detailed analysis of Mentha suaveolens ssp. insularis (Req.) Greuter essential oil (EO) and hydrolate extract (HE) was carried out by combination of GC–RI, GC–MS and 13C‐NMR spectroscopy. After fractionation by column chromatography, 51 components of the EO and 27 components of the HE, accounting for 96.1% and 98.3%, respectively, were identified. The main components were pulegone (44.4% and 14.8%) and cis‐cis‐p‐menthenolide (27.3% and 67.3%). This α‐methylen‐γ‐butyrolactone, reported for the first time as a natural product, was isolated and its structure elucidated by 1D and 2D NMR spectroscopy. Both EO and HE exhibited a fair antibacterial activity against Staphylococcus aureus and Bacillus cereus. Copyright © 2008 John Wiley & Sons, Ltd.
Analysis of tissue‐specific emission of volatiles by the flowers of six Camellia species
Authors: Jullien Frédéric , Gao Jiyin , Orel George , Legendre Laurent
Published: April 2008

Scent production is a rare phenomenon in the genus Camellia, which is otherwise very diverse. This study provides the first report of GC–MS analyses of the volatile compounds synthesized and emitted by six Camellia species belonging to three subgenera. Solvent extracts mainly contained derivatives of the terpenoid, phenylpropanoid and fatty acid metabolisms. Members of subgenus Metacamellia mainly accumulated 2‐phenylethanol, while C. japonica of subgenus Camellia mainly synthesized monoterpenes and C. yuhsienensis of subgenus Paracamellia displayed a balanced mix of constituents. Headspace analysis of emitted volatiles confirmed the volatile composition and the rosy note of the scent of all species (due to 2‐phenylethanol, (±) linalool and some of their derivatives). Analysis of dissected tissues revealed that stamens accumulated 3–50 times more volatiles than petals and that carpels and sepals were the weakest producers of volatiles. These latter organs were the main source of heptanol. Phenylpropanoid and terpenoid derivatives accumulated differentially in both petals and stamens. Tissue distribution differed among Camellia species. Copyright © 2008 John Wiley & Sons, Ltd.
Diterpene‐rich needle oil of Pinus pinaster Ait. from Corsica
Authors: Ottavioli Josephine , Bighelli Ange , Casanova Joseph
Published: April 2008

The composition of 46 samples of needle oil of maritime pine (Pinus pinaster Ait.) from Corsica was investigated by gas chromatography (GC) in combination with retention indices, GC–MS and 13C‐NMR. Sixty compounds, accounting for 82.9–97.0% of the oil, were identified. The oils consisted mainly of mono‐, sesqui‐ and diterpene hydrocarbons, especially α‐pinene (6.4–29.4%), (E)‐β‐caryophyllene (4.4–19.9%), germacrene D (1.7–21.4%) and abieta‐7,13‐diene (6.8–34.2%). Although the composition varied substantially from sample to sample, k‐means partitioning and principal component analysis (PCA) of the compositional data suggested the occurrence of only one group within the 46 individual samples. The composition dominated by diterpene hydrocarbons (up to 61%) is reported for the first time. Copyright © 2008 John Wiley & Sons, Ltd.
Composition of essential oil from seeds of Nigella sativa L. cultivated in Poland
Authors: Wajs Anna , Bonikowski Radoslaw , Kalemba Danuta
Published: April 2008

Forty‐eight compounds have been identified in the essential oil from Nigella sativa (black cumin) seeds, 14 of which are volatiles that have never been isolated from black cumin before. This is the first time to show two monoterpenoids: cis‐ and trans‐4‐methoxythujane, occur naturally in plants, specifically in the essential oil from N. sativa seeds in 0.3% and 4%, respectively. The structures of the 4‐methoxythujanes were established by both spectroscopic and chemical methods. Copyright © 2008 John Wiley & Sons, Ltd.
Variation in the chemical composition and yield of essential oil of rose‐scented geranium (Pelargonium sp.) by the foliar application of metallic salts
Authors: Prasad Arun , Chattopadhyay Amitabha , Yadav Anju , Kumari Raj
Published: April 2008

The effects of foliar application of metallic salts (0.5% aqueous solution of sodium chloride, calcium chloride, iron sulphate, zinc sulphate, copper sulphate and nickel sulphate) on the chemical composition and yield of essential oil of rose‐scented geranium (Pelargonium sp.) was studied in a pot experiment. The content of linalool, geraniol and 10‐epi‐γ‐eudesmol in the geranium oil significantly increased and that of geranial and β‐bourbonene decreased by the foliar application of metallic salts as compared to control plants. The increase in the content was 53.3%, 15.8%, 6.6%, 109.2%, 13.3% and 54.2% in linalool and 17.8%, 26.8%, 39.1%, 36.6%, 24.8% and 38.8% in geraniol over the control by the application of sodium chloride, calcium chloride, iron sulphate, zinc sulphate, copper sulphate and nickel sulphate, respectively. The content of 10‐epi‐γ‐eudesmol was increased by 24.2%, 16.3%, 36.9%, 24.2%, 17.1% and 23.7% over the control by the application of sodium chloride, calcium chloride, iron sulphate, zinc sulphate, copper sulphate and nickel sulphate, respectively. The level of cis‐ and trans‐rose oxide in geranium oil significantly increased and that of neral decreased by the application of sodium chlorides, zinc sulphate and nickel sulphate as compared to control. cis‐3‐Hexenol, isomenthone, neo‐isomenthol, citronellol and citronellyl formate 2‐phenylethyl tiglate and geranyl tiglate content in geranium oil was not significantly affected by the foliar application of metallic salts. The herbage and oil yield of geranium significantly increased by the foliar application of metallic salts as compared with control plants. The increase in yield was 9.9%, 9.4%, 30.6%, 29.7%, 28.6% and 21.6% in herbage and 41.9%, 23.4%, 29.6%, 29.6%, 41.9% and 41.9% in oil yield over control by the application of sodium chloride, calcium chloride, iron sulphate, zinc sulphate, copper sulphate and nickel sulphate, respectively. The oil content in the geranium was enhanced by the application of sodium chloride, calcium chloride, copper sulphate and nickel sulphate, whereas application of iron sulphate and zinc sulphate had no significant effect on the oil content. Copyright © 2008 John Wiley & Sons, Ltd.
In vitro study on the anticandidal activity of Melaleuca alternifolia (tea tree) essential oil combined with chitosan
Authors: Juliano Claudia , Demurtas Carla , Piu Luisella
Published: April 2008

The in vitro activities of commercial Melaleuca alternifolia essential oil (tea tree oil; TTO) and chitosan were investigated against Candida albicans, both alone and in combination, to assess their potential synergistic action; their anticandidal properties were assessed using standard microbiological techniques, such as MIC evaluation and a ‘time–kill’ test. Our results demonstrated that both TTO and chitosan possess remarkable activity against Candida: TTO inhibited C. albicans at 0.5 % v/v and was able to kill yeast cells in 120 min at 1% and in 300 min at 0.5–0.25%; as far as chitosan was concerned, 0.5 mg/ml were required to inhibit Candida growth in liquid medium, whereas 0.5–2 mg/ml chitosan required 24 h to kill them in the ‘time–kill’ test; this effect was pH‐dependent, being present at pH 5.0 and disappearing at pH 2.0. When TTO and chitosan were tested together, the polymer reduced the MIC of TTO but did not enhance the activity of the oil as evaluated in the ‘time–kill’ test. Copyright © 2008 John Wiley & Sons, Ltd.
Antioxidant activity and characterization of volatile extracts of Capsicum annuum L. and Allium spp.
Authors: Jang Hae‐Won , Ka Mi‐Hyun , Lee Kwang‐Geun
Published: April 2008

Plants that are commonly used in kimchi, a traditional Korean fermented food, include Capsicum annuum L. (green pepper), Allium fistulosum L. (Welsh onion), Allium cepa L. (onion) and Allium scorodoprasm L. (garlic), each of which has its own aroma. Aroma extracts of the plants were isolated by steam distillation under reduced pressure (DRP) and liquid–liquid continuous extraction (LLE). The aroma extracts were identified by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The major aroma compounds of the plant extracts were sulphides, alcohols and heterocyclic compounds. Antioxidant activities of the aroma extracts were evaluated using two different assays. The aroma extracts isolated from green pepper, Welsh onion, onion and garlic inhibited the oxidation of hexanal by 51%, 95%, 96% and 98%, respectively, for 1 month at a level of 500 µg/ml; these extracts inhibited malonaldehyde formation from cod liver oil by 49%, 58%, 62% and 58%, respectively, at a level of 500 µg/ml. Their antioxidant activities were comparable to that of the natural antioxidant α‐tocopherol. Copyright © 2008 John Wiley & Sons, Ltd.
Thermal Conductivity and Contact Resistance of Compressed Gas Diffusion Layer of PEM Fuel Cell
Authors: Nitta I. , Himanen O. , Mikkola M.
Published: April 2008

This paper discusses the effect of compression pressure on the mechanical and thermal properties of gas diffusion layers (GDL). The stress–strain curve of the GDL revealed one nonlinear and two piecewise linear regions within the compression pressure range of 0–5.5 MPa. The thermal conductivity of the compressed GDL seems to be independent of the compression pressure and was determined to be 1.18 ± 0.11 W m–1 K–1 at room temperature. The thermal contact resistance between the GDL and graphite was evaluated by augmenting experiments with computer modelling. The thermal contact resistance decreased nonlinearly with increasing compression pressure. According to the results here, the thermal bulk resistance of the GDL is comparable to the thermal contact resistance between the GDL and graphite. A simple one‐dimensional model predicted a temperature drop of 1.7–4.4 °C across the GDL and catalyst layer depending on compression pressures.
Experimental Studies on the Influence of Operational Parameters on the Cold Start of a 2 kW Fuel Cell
Authors: Bégot S. , Harel F. , Kauffmann J. M.
Published: April 2008

In this paper, experimental investigations on the influence of operational parameters on PEM fuel cell cold start are presented. The effect of current density, stack impedance at 1 kHz prior to start, as well as gas flow rate, gas pressure, coolant flow rate and surrounding subfreezing temperature are studied. The experimental apparatus is briefly described. It includes a main unit at room temperature and a smaller separate unit in a climatic chamber. Low current density, high impedance prior to start, moderate subfreezing temperature (–5 °C), high gas flow rate, low gas pressure and low coolant flow rate are found to have a positive impact on the cold start performance. Combining these parameters, self start‐up of the fuel cell without additional energy is achieved at –5 °C in 30 min. The whole set of observations leads to the following hypotheses on freeze mechanism: in the first phase, dry membranes and low current lead to a transient phase of membrane humidification. Then, in the second phase, ice clogging of the active layers occurs. In the third phase, a variable quantity of the produced water reaches the gas diffusion layers and channels.
Inferring disability status from corrupt data
Authors: Kreider Brent , Pepper John
Published: April 2008

In light of widespread concerns about the reliability of self‐reported disability, we investigate what can be learned about the prevalence of work disability under various assumptions on the reporting error process. Developing a nonparametric bounding framework, we provide tight inferences under our strongest assumptions but then find that identification deteriorates rapidly as the assumptions are relaxed. For example, we find that inferences are highly sensitive to how one models potential inconsistencies between subjective self‐assessments of work limitation and more objective measures of functional limitation. These two indicators appear to measure markedly different aspects of health status. Copyright © 2008 John Wiley & Sons, Ltd.
From temporary help jobs to permanent employment: what can we learn from matching estimators and their sensitivity?
Authors: Ichino Andrea , Mealli Fabrizia , Nannicini Tommaso
Published: April 2008

The diffusion of temporary work agency (TWA) jobs has led to a harsh policy debate and ambiguous empirical evidence. Results for the USA, based on quasi‐experimental evidence, suggest that a TWA assignment decreases the probability of finding a stable job, while results for Europe, based on the conditional independence assumption (CIA), typically reach opposite conclusions. Using data for two Italian regions, we rely on a matching estimator to show that TWA assignments can be an effective springboard to permanent employment. We also propose a simulation‐based sensitivity analysis, which highlights that only for one of these two regions are our results robust to specific failures of the CIA. We conclude that European studies based on the CIA should not be automatically discarded, but should be put under the scrutiny of a sensitivity analysis like the one we propose. Copyright © 2008 John Wiley & Sons, Ltd.
Two decadally resolved records from north‐west European peat bogs show rapid climate changes associated with solar variability during the mid–late Holocene
Authors: Mauquoy Dmitri , Yeloff Dan , Van Geel Bas , Charman Dan J. , Blundell Antony
Published: April 2008

Two 14C accelerator mass spectrometry (AMS) wiggle‐match dated peat sequences from Denmark and northern England record changes in mire surface wetness reconstructed using plant macrofossil and testate amoebae analyses. A number of significant mid–late Holocene climatic deteriorations (wet shifts) associated with declines in solar activity were recorded (at ca. 2150 cal. yr BC, 740 cal. yr BC, cal. yr AD 930, cal. yr AD 1020, cal. yr AD 1280–1300, cal. yr AD 1640 and cal. yr AD 1790–1830). The wet shifts identified from ca. cal. yr AD 930 are concurrent with or lag decreases in solar activity by 10–50 years. These changes are replicated by previous records from these and other sites in the region and the new records provide improved precision for the ages of these changes. The rapidly accumulating (up to 2–3 yr cm−1, ∼1310 yr old, 34 14C dates) Danish profile offers an unprecedented high‐resolution record of climate change from a peat bog, and has effectively recorded a number of significant but short‐lived climate change events since ca. cal. yr AD 690. The longer time intervals between samples and the greater length of time resolved by each sample in the British site due to slower peat accumulation rates (up to 11 yr cm−1, ∼5250 yr old, 42 14C dates) acted as a natural smoothing filter preventing the clear registration of some of the rapid climate change events. Not all the significant rises in water table registered in the peat bog archives of the British and Danish sites have been caused by solar forcing, and may be the result of other processes such as changes in other external forcing factors, the internal variability of the climate system or raised bog ecosystem. Copyright © 2008 John Wiley & Sons, Ltd.
Predictability of price of tea from sensory assessments and biochemical information using data‐mining techniques
Authors: Paul Sanjoy K
Published: April 2008

BACKGROUND: The valuation of tea depends on the sensory assessments made by the Brokers and Buyers (Tea Tasters) to a large extent, though the market conditions and the requirements of a particular Buyer play an important role in determining the basic prices of teas. Again, there are several biochemical quality parameters in tea on which the quality of a particular tea depends. It is not straightforward to establish the reflection of biochemical quality characteristics in tea on the Taster's sensory assessments and price because of the complex dynamics within chemical properties and the inherent subjectivity of quality evaluation through the Taster's scores. It is, however, important to judge the market valuation of teas from quality assessments and biochemical properties. This paper describes the advantages of using statistical data‐mining techniques to explore the association of biochemical quality parameters in teas with the Taster's sensory assessments, and the application of a nonparametric statistical technique, multivariate adaptive regression splines (MARSplines), to establish the predictability of the realised prices of teas from sensory assessments.

RESULTS: The price of tea is significantly associated with various quality attributes and some of the biochemical parameters. The MARSplines technique successfully demonstrated the predictability of price through Tasters' sensory assessments and also raised the issue of inherent subjectivity of the Tasters' assessments.

CONCLUSION: It is important to explore appropriate statistical techniques to assess the subjectivity in Tasters' assessments, and a better‐designed study needs to be conducted to understand the complex biochemical reflections on the price of tea. Copyright © 2008 Society of Chemical Industry
Chiral separations in sub‐ and supercritical fluid chromatography
Authors: Mangelings Debby , Vander Heyden Yvan
Published: April 2008

Sub‐ and supercritical fluid chromatography (SFC) received more and more attention in pharmaceutical analysis during the last years. Especially for chiral separations, this technique is becoming increasingly popular. This review gives an overview of most chiral separation applications using SFC, covering the literature from 2000 on.
The advantages of ESI‐MS detection in conjunction with HILIC mode separations: Fundamentals and applications
Authors: Nguyen Hien P. , Schug Kevin A.
Published: April 2008

The analysis of highly hydrophilic, ionic, and polar compounds has been performed by HILIC‐ESI‐MS for the last few years. The use of low aqueous/high polar organic solvent content in HILIC separation mobile phase is almost ideal for ESI‐MS detection in many cases, resulting in increased sensitivity. Although the addition of modifiers such as acids or salts is necessary in some circumstances for a good separation, the optimum concentrations used are still highly amenable for ESI‐MS analysis, showing few deleterious effects. In this review, the mechanism of HILIC separation and ESI ion generation will be briefly discussed, followed by a summary of method development and applications in several fields of research including pharmaceutical, biomolecular, food, metabolic, and environmental analysis.
Grafting BSA onto Poly[(L‐lactide)‐co‐carbonate] Microspheres by Click Chemistry
Authors: Han Yadong , Shi Quan , Hu Junli , Du Qing , Chen Xuesi , Jing Xiabin
Published: April 2008

Model protein bovine serum albumin (BSA) was covalently grafted onto poly[(L‐lactide)‐co‐carbonate] microsphere surfaces by “click chemistry.” The grafting was confirmed by confocal laser scanning microscopy and X‐ray photoelectron spectroscopy. The maximum amount of surface‐grafted BSA was 45 mg · g−1. The secondary structure of the grafted BSA was analyzed by FTIR and the results demonstrated that the grafting did not affect protein structure. This strategy can also be used on microspheres prepared from poly(L‐lactide)/poly[(L‐lactide)‐co‐carbonate] blend materials.

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Release of Prostaglandin E1 from N‐(2‐Hydroxypropyl)methacrylamide Copolymer Conjugates by Bone Cells
Authors: Pan Huaizhong , Liu Jihua , Dong Yuanyi , Sima Monika , Kopečková Pavla , Brandi Maria Luisa , Kopeček Jindřich
Published: April 2008

Bone‐targeting N‐(2‐hydroxypropyl)methacrylamide (HPMA) copolymer‐PGE1 conjugates, containing cathepsin K sensitive spacers, were incubated with induced osteoclasts and osteoblasts, their precursors, and control non‐skeletal cells. The release of PGE1 was monitored by an HPLC assay. In both murine and human cell lines, osteoclasts appeared to be the most active cells in the cleavage (PGE1 release). Incubation with osteoblasts also resulted in fast PGE1 release, whereas precursor and control cells released PGE1 with a substantially slower rate than bone cells (apparently through ester bond cleavage). Experiments in the presence of inhibitors revealed that other enzymes, in addition to cathepsin K, were participating in the cleavage of the conjugate. Confocal fluorescence studies exposed internalization of the conjugate by endocytosis with ultimate localization in the lysosomal/endosomal compartment.

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Effect of pre‐oxidation on coke formation and metal dusting of electroplated Ni3Al–CeO2‐based coatings in CO–H2–H2O
Authors: Liu H. , Chen W.
Published: April 2008

Pre‐oxidation was introduced to improve the resistance of electroplated pure, 5 µm CeO2‐dispersed, and 9–15 nm CeO2‐dispersed Ni3Al coatings to coke formation and metal dusting in 24.4%CO–73.3%H2–2.3%H2O at 650 °C. Coke formation and metal dusting of pre‐oxidized Ni3Al‐based coatings were retarded up to 200 h owing to a thin Al2O3 scale induced during pre‐oxidation. The long‐term effectiveness of pre‐oxidation nonetheless depended on the integrity of Al2O3 scale. The pure Ni3Al coating suffered severe spallation after pre‐oxidation and thereby showed the worst long‐term resistance. Two pre‐treated 9–15 nm CeO2‐dispersed Ni3Al coatings exhibited the best long‐term resistance to carbon attack because nano‐CeO2 particles maintained a full coverage of Al2O3 scale on the coatings. Two 5 µm CeO2‐dispersed Ni3Al coatings showed significant spallation after pre‐oxidation because of an overdoping effect and experienced coke formation and metal dusting during long‐term exposure.
Corrosion protection properties of copper‐ and carbon‐containing polyethylene films in humid air climates
Authors: Köhler S. , Rammelt U. , Reinhard G.
Published: April 2008

The corrosion protection properties of commercially available polyethylene (PE) films containing copper and carbon were investigated and compared with pure PE films of comparable thickness. The composition of these films was analyzed by thermoanalysis and atom emission spectroscopy (ICP‐AES). Electrochemical impedance spectroscopy (EIS) and packaging tests were used to determine the ability of copper‐ and carbon‐containing PE films to protect mild steel against corrosion in humid air climates. For the here‐investigated samples, no electrochemical activity of copper could be found under these conditions. In contrast to the added copper only the inserted carbon decreased the surface resistance. Additional abrasive tests imply that copper is encapsulated inside the films. For all samples, the permeability to vapor and the insertion of water were similar to the copper and carbon free reference film. The tests in the climate cabinet revealed that mild steel samples packed in copper‐ and carbon‐containing films reached the same degree of corrosion than those in the reference films.
Hydrogen degradation of structural steels in technical hydrocarbon liquids
Authors: Swieczko‐Zurek B. , Zielinski A. , Lunarska E.
Published: April 2008

Hydrogen absorption, mechanical testing under different loading mode and electrochemical measurement were done for 0.3C low alloy steels used in the ship engine parts at immersion in the boiler fuel and in the used engine mineral oil at elevated temperatures corresponding to the operating conditions. The hydrogen charging of steels has been found to reach a level causing their plasticity loss. No effect, a plasticity loss and a significant decrease in the number of cycles have been stated in constant load, slow strain rate and fatigue tests, respectively. The results showed the local active plastic deformation proceeded close to the surface of hydrogen ingress to provide the highest possibility for hydrogen induced metal degradation in hydrocarbon environments. Although the source of hydrogen evolved in the case of technical hydrocarbons has been discussed, the promoting effect of formed H2S should be recognized as the important factor influencing the hydrogen charging from those environments. Some variation in the steel microstructure, chemical composition and hardness of steels, even allowed by the standard may affect their susceptibility to hydrogen degradation in hydrocarbons.
Galvanic compatibility of corrosion protective coatings with AA7075 aluminum alloy
Authors: Lodhi Z. F. , Hamer W. J. , Mol J. M. C. , Terryn H. , de Wit J. H. W.
Published: April 2008

The galvanic compatibility of aerospace aluminum alloy AA7075 with cadmium (Cd), zinc (Zn), and zinc–cobalt–iron (Zn–Co–Fe, 32–37%Co and 1%Fe) alloys was investigated. A comparison of open circuit potential [OCP vs. saturated calomel electrode (SCE)] measurements in 0.6 mM NaCl showed that all coatings would act anodically to AA7075 with an exception of Zn–Co–Fe (37%Co + 1%Fe) alloy which was electropositive to AA7075. During the zero resistance ammetry (ZRA) measurement in 0.6 M NaCl electrolyte the coupled OCP and current density were measured during 7 days of immersion and both Zn and Cd acted anodic and thus sacrificial to AA7075. Galvanic coupling of AA7075 with (37%Co + 1%Fe) Zn–Co–Fe alloy resulted in the consequent dissolution of the AA7075 aluminum alloy. In contrast, Zn–Co–Fe (32%Co + 1%Fe) alloy was found to be anodic to AA7075 during the first 26 h of immersion but after dezincification and cobalt enrichment at the surface became cathodic to the AA7075 aluminum alloy. During coupling with Zn, some pitting was also observed on AA7075.
Electrodeposited nickel/alumina composite coating on NdFeB permanent magnets
Authors: Zhang H. , Song Y. W. , Song Z. L.
Published: April 2008

NdFeB magnets are highly susceptible to corrosion in various environments. A nickel/alumina composite coating for NdFeB magnets was investigated in this paper. The microstructures of electrodeposited nickel coating and nickel/alumina composite coating were determined by scanning electron microscope (SEM). The corrosion behavior of nickel coating and nickel/alumina composite coating in 3.5 wt% sodium chloride solution was studied by polarization curves and electrochemical impedance spectroscopy (EIS). The results show that the nickel coating and nickel/alumina composite coating can both provide adequate protection to the NdFeB substrate. Furthermore, the free corrosion potential of nickel/alumina composite coating is more positive and the passivation region is more obvious compared with nickel coating, and the capacitance loop diameter of nickel/alumina composite coating is significantly larger than that of nickel coating. With the increase in immersion time, a flat of passivation film is formed on the surface of nickel/alumina composite coating, resulting in excellent corrosion resistance after 288 h immersion in 3.5% sodium chloride solution according to EIS testing.
Recent Advances in Reactive Extrusion Processing of Biodegradable Polymer‐Based Compositions
Authors: Raquez Jean‐Marie , Narayan Ramani , Dubois Philippe
Published: April 2008

This review reports on recent advances in the design of biodegradable polymers built from petroleum and renewable resources using reactive extrusion processing. Reactive extrusion represents a unique tool to manufacture biodegradable polymers upon different types of reactive modification in a cost‐effective way. Partially based on our ongoing research, ring‐opening polymerization of biodegradable polyesters will be approached as well as the chemical modification of biodegradable polymers, particularly natural polymers. The development of environmentally friendly polymer blends as well as (nano)composites from natural polymers, including natural fibers and nanoclays, through reactive extrusion, as an efficient way to improve the interfacial adhesion between these components, will be also discussed.

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Ferroelectric Polymer Nanotubes with Large Dielectric Constants for Potential All‐Organic Electronic Devices
Authors: Wang Chang‐Chun , Shen Qun‐Dong , Tang Shao‐Chun , Wu Qiang , Bao Hui‐Min , Yang Chang‐Zheng , Jiang Xi‐Qun
Published: April 2008

To fabricate ferroelectric ultrathin polymer films with large dielectric constants for potential all‐organic electronic devices, ferroelectric polymer nanotubes and a composite of the nanotubes with a dispersed organic semiconductor have been fabricated by template‐assisted methods. The ferroelectricity drops markedly in spin‐coated ultrathin films less than 100 nm thick, whereas P(VDF‐TrFE) nanotubes with a wall thickness of a few ten nm sustain ferroelectricity. The composite nanotubes exhibit a giant dielectric constant as a result of significantly enhanced interface polarization between the nanosized fillers and the polymer matrix. They could be of practical use in supercapacitors, optoelectronic devices, and sensors.

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Responsive Polymer‐Protein Bioconjugates Prepared by RAFT Polymerization and Copper‐Catalyzed Azide‐Alkyne Click Chemistry
Authors: Li Ming , De Priyadarsi , Gondi Sudershan R. , Sumerlin Brent S.
Published: April 2008

Responsive polymer‐protein conjugates were synthesized by combination of reversible addition‐fragmentation chain transfer (RAFT) polymerization and a grafting‐to approach by a highly efficient “click chemistry” strategy. A model protein, bovine serum albumin (BSA), was functionalized with an alkyne moiety by reaction of its free cysteine residue with propargyl maleimide. Azido‐terminated poly(N‐isopropylacrylamide) (PNIPAM‐N3) was prepared via RAFT, and polymer‐protein coupling was accomplished by copper‐catalyzed azide‐alkyne cycloaddition. In aqueous solution, the conjugates were observed by dynamic light scattering to be larger than the free polymer or the unmodified protein. Upon heating above the PNIPAM lower critical solution temperature (LCST), the PNIPAM‐BSA bioconjugates formed stable nanoparticles composed of dehydrated polymer and hydrophilic protein.

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1H chemical shifts in NMR. Part 27: proton chemical shifts in sulfoxides and sulfones and the magnetic anisotropy, electric field and steric effects of the SO bond
Authors: Abraham Raymond J. , Byrne Jonathan J. , Griffiths Lee
Published: April 2008

The 1H chemical shifts of a series of sulfoxide and sulfone compounds in CDCl3 solvent were obtained from experiment and the literature. These included dialkyl sulfoxides and sulfones (R2SO/R2SO2, R = Me, Et, Pr, n‐Bu), the cyclic compounds tetramethylene sulfoxide/sulfone, pentamethylene sulfoxide/sulfone and the aromatic compounds p‐tolylmethylsulfoxide, dibenzothiopheneoxide/dioxide, E‐9‐phenanthrylmethylsulfoxide and (E) (Z)‐1‐methylsulfinyl‐2‐methylnaphthalene. The spectra of the pentamethylene SO and SO2 compounds were obtained at −70 °C to obtain the spectra from the separate conformers (SO) and from the noninverting ring (SO2). This allowed the determination of the substituent chemical shifts (SCS) of the SO and SO2 functional groups, which were analyzed in terms of the SO bond electric field, magnetic anisotropy and steric effect for long‐range protons together with a model (CHARGE8d) for the calculation of the two and three bond effects. After parameterization, the overall root mean square (RMS) error (observed‐calculated) for a dataset of 354 1H chemical shifts was 0.11 ppm. The anisotropy of the SO bond was found to be very small, supporting the dominant single bond S+O− character of this bond. Copyright © 2008 John Wiley & Sons, Ltd.