bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of pretreatment on the surface characteristics of PLLA fibers and subsequent hydroxyapatite coating
Authors: Peng F. , Olson J.R. , Shaw M.T. , Wei M.
Published: August 2008

A fibrous precursor for bone repair composites was made by coating poly(L‐lactide) (PLLA) fibers with hydroxyapatite (HA) using a biomimetic method. To enhance the bonding between the HA coating and the PLLA fiber, PLLA fibers were etched with either sodium hydroxide or sodium hypochlorite to generate carboxyl groups on fiber surfaces. The experiments were designed to determine the influence of etching on the fiber surface morphology and chemistry as well as the subsequent HA coating on the etched fiber surfaces. It was found that the etching pretreatment increased the roughness as well as the hydrophilicity of fibers, indicating that hydrolysis of PLLA chains had taken place on fiber surfaces. The etching pretreatment also promoted HA coating formation by introducing thicker coating on the surface of fibers with a longer etching time, a higher etching concentration, or with NaOCl as the etching agent. A mechanism of surface hydrolysis and oxidation of PLLA was proposed. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Intruder states in multireference perturbation theory: The ground state of manganese dimer
Authors: Camacho Cristopher , Witek Henryk A. , Yamamoto Shigeyoshi
Published: August 2008

A detailed analysis of a severe intruder state problem in the multistate multireference perturbation theory (MS‐MRPT) calculations on the ground state of manganese dimer is presented. An enormous number of detected intruder states (> 5000) do not permit finding even an approximate shape of the X1Σ potential energy curve. The intruder states are explicitly demonstrated to originate from quasidegeneracies in the zeroth‐order Hamiltonian spectrum. The electronic configurations responsible for appearance of the quasidegeneracies are identified as single and double excitations from the active orbitals to the external orbitals. It is shown that the quasidegeneracy problem can be completely eliminated using shift techniques despite of its severity. The resultant curves are smooth and continuous. Unfortunately, strong dependence of the spectroscopic parameters of the X1Σ state on the shift parameter is observed. This finding rises serious controversies regarding validity of employing shift techniques for solving the intruder state problem in MS‐MRPT. Various alternative approaches of removing intruder states (e.g., modification of the basis set or changing the active space) are tested. None of these conventional techniques is able to fully avoid the quasidegeneracies. We believe that the MS‐MRPT calculations on the three lowest Ag states of manganese dimer constitute a perfect benchmark case for studying the behavior of MRPT in extreme situations. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Estimation and extraction of B‐cell linear epitopes predicted by mathematical morphology approaches
Authors: Chang Hao‐Teng , Liu Chih‐Hong , Pai Tun‐Wen
Published: August 2008

B‐cell epitope prediction facilitates the design and synthesis of short peptides for various immunological applications. Several algorithms have been developed to predict B‐cell linear epitopes (LEs) from primary sequences of antigens, providing important information for immunobiological experiments and antibody design. This paper describes two robust methods, LE prediction with/without local peak extraction (LEP‐LP and LEP‐NLP), based on antigenicity scale and mathematical morphology for the prediction of B‐cell LEs. Previous studies revealed that LEs could occur in regions with low‐to‐moderate but not globally high antigenicity scales. Hence, we developed a method adopting mathematical morphology to extract local peaks from a linear combination of the propensity scales of physico‐chemical characteristics at each antigen residue. Comparison among LEP‐LP/LEP‐NLP, BepiPred and BEPITOPE revealed that our algorithms performed better in retrieving epitopes with low‐to‐moderate antigenicity and achieved comparable performance according to receiver operation characteristics (ROC) curve analysis. Of the identified LEs, over 30% were unable to be predicted by BepiPred and BEPITOPE employing an average threshold of antigenicity index or default settings. Our LEP‐LP method provides a bioinformatics approach for predicting B‐cell LEs with low‐ to‐moderate antigenicity. The web‐based server was established at http://biotools.cs.ntou.edu.tw/lepd_antigenicity. php for free use. Copyright © 2008 John Wiley & Sons, Ltd.
Excitatory effects of low‐level lead exposure on action potential firing of pyramidal neurons in CA1 region of rat hippocampal slices
Authors: Yan Dan , Xiao Cheng , Ma Fang‐li , Wang Lang , Luo Yun‐Yun , Liu Jin , Wang Hui‐Li , Chen Ju‐Tao , Ruan Di‐Yun
Published: August 2008

Lead is putatively regarded as an environmental neurotoxicant. Long‐term low‐level lead exposure causes cognitive deficits, but the mechanism remains to be elucidated. In the present study, the excitatory effects of low‐level lead exposure on action potential (AP) firing of pyramidal neurons in CA1 region of rat hippocampal slices and the pathway through which lead induced these effects were studied with conventional whole‐cell recording. Low‐level lead (0.5 and 5 μM) exposure did not significantly change either voltage threshold or amplitude, duration, rise time, or rising velocity of single AP; conversely, 5 μM lead exposure significantly increased AP firing rates and reduced spike frequency adaptation. These excitatory effects of 5 μM lead were blocked by mibefradil, a selective blocker of T‐type voltage‐dependent calcium channels (VDCC), but not by verapamil and ω‐conotoxin, selective blockers of L‐ type and N‐type VDCC, respectively. Five micromolar lead could not change the excitability of pyramidal neurons when slices were perfused with calcium‐free ACSF. In addition, the effects were abolished by inhibitors of two intracellular calcium release channels: 2‐APB, an inhibitor of inositol trisphosphate receptors, and dantrolene, an inhibitor of ryanodine receptors, but not by thapsigargin, an inhibitor of endoplasmic reticulum calcium uptake. These results provide evidence for excitatory neurotoxicity of low‐level lead exposure, contribution of T‐type VDCC in the entrance of lead into neurons, and a possible involvement of calcium flux alteration during APs in this excitatory neurotoxicity. © 2008 Wiley‐Liss, Inc.
Effect of delayed storage and continuous ethylene exposure on flesh reddening of ‘Royal Diamond’ plums
Authors: Manganaris George A , Vicente Ariel R , Crisosto Carlos H , Labavitch John M
Published: August 2008

BACKGROUND: Flesh reddening has been described as one of the manifestations of plum fruits to low‐temperature storage for prolonged periods. The influence of factors such as ethylene and delayed storage has not been studied to date. In order to assess that, plum cv. ‘Royal Diamond’ fruits were (a) stored at 5 °C (control), (b) held at 20 °C for 2 days before storage at 5 °C (delayed storage) or (c) maintained at 5 °C under 15 µL L−1 ethylene. Fruits were then transferred to 20 °C and ethylene, respiration, weight loss, firmness, soluble solids content, acidity, flesh reddening, anthocyanin accumulation and phenylalanine ammonia‐lyase (PAL) activity were determined.

RESULTS: Delayed storage fruits showed more extensive flesh reddening than control fruits, with increased PAL activity and higher anthocyanin accumulation. Symptoms were expressed more markedly when fruits were stored at 5 °C in ethylene.

CONCLUSION: Results indicated that the fruit ripening stage is a critical factor determining the susceptibility of ‘Royal Diamond’ plums to flesh reddening. Fruits continuously exposed to ethylene showed a dramatic increase in reddening, suggesting that ethylene contributes to the development of the disorder. Copyright © 2008 Society of Chemical Industry
Laser applications and system considerations in ocular imaging
Authors: Elsner A.E. , Muller M.S.
Published: August 2008

We review laser applications for primarily in‐vivo ocular imaging techniques, describing their constraints based on biological tissue properties, safety, and the performance of the imaging system. We discuss the need for cost‐effective sources with practical wavelength‐tuning capabilities for spectral studies. Techniques to probe the pathological changes of layers beneath the highly scattering retina and diagnose the onset of various eye diseases are described. The recent development of several optical‐coherence‐tomography‐based systems for functional ocular imaging is reviewed, as well as linear and nonlinear ocular‐imaging techniques performed with ultrafast lasers, emphasizing recent source developments and methods to enhance imaging contrast.
Molecular Flexibility of Methylcelluloses of Differing Degree of Substitution by Combined Sedimentation and Viscosity Analysis
Authors: Patel Trushar R. , Morris Gordon A. , de la Torre Jose Garcia , Ortega Alvaro , Mischnick Petra , Harding Stephen E.
Published: August 2008

The flexibility/rigidity of methylcelluloses (MCs) plays an important part in their structure–function relationship and therefore on their commercial applications in the food and biomedical industries. In the present study, two MCs of low degree of substitution (DS) 1.09 and 1.32 and four of high DS (1.80, 1.86, 1.88 and 1.93) were characterised in distilled water in terms of intrinsic viscosity [η]; sedimentation coefficient ($s_{20,{\rm w}}^0$) and weight average molar mass ($\overline M _{\rm w}$). Solution conformation and flexibility were estimated qualitatively using conformation zoning and quantitatively (persistence length Lp) using the new combined global method. Sedimentation conformation zoning showed an extended coil (Type C) conformation and the global method applied to each MC sample yielded persistence lengths all within the range Lp = 12–17 nm (for a fixed mass per unit length) with no evidence of any significant change in flexibility with DS.

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Evolution of corrosion in cast Al alloy in antifreeze radiator coolant
Authors: Zhou W. , Aung N. N. , Choudhary A. , Kanouni M.
Published: August 2008

Corrosion is an important issue for cast Al alloy in an engine cooling system, but how the microstructural features affect the coolant‐related corrosion behaviour is not well understood. In this research, the evolution of corrosion in an ISO 2379 cast Al alloy was studied in an antifreeze radiator coolant under heat‐rejecting conditions. Extensive analyses of microstructures and corroded surfaces were carried out using an optical microscope, scanning electron microscope equipped with energy dispersive spectroscopy and X‐ray diffractometer. Intergranular cavitation corrosion was observed to occur at interfaces between α‐Al matrix and intermetallics (Al2Cu and Al5FeSi) or to a less degree at interfaces between α‐Al matrix and Si phase. The large area fraction of the cathodic phases (Al2Cu, Al5FeSi and Si) led to the galvanic coupling between them and the adjacent anodic α‐Al matrix. The heat‐rejecting condition in antifreeze radiator coolant was favourable condition to cavitation process while severe crevice corrosion was predominant at oxygen‐depleted regions in the heat‐transfer corrosion cell.
Pitting corrosion of sheets of a nickel‐base superalloy
Authors: Rao M. N.
Published: August 2008

Cold rolled sheets of a nickel‐base superalloy are used in building gas turbine engines. After rolling to the final gauge, the sheets were annealed at 1180 °C. Pickling of the sheets was carried out to remove the scale and the oxidized layer. It was observed that there was heavy incidence of pitting with perforations at several locations due to pits penetrating through the thickness. The sheets got rejected, resulting in heavy loss. The superalloy contains 25 wt% chromium, 15 wt% tungsten. Tungsten provides high resistance to pitting corrosion. With such a high level of W, the grade has a high Pitting Resistance Equivalent. Further it is a single‐phase material. Pitting attack is thus totally unexpected. The failure was analyzed. Pickling process for this material normally involves the usage of salt bath, sulfuric acid, nitric acid, and/or hydrofluoric‐nitric acid baths. In the case under study, satisfactory pickling was not achieved this way; discoloration and deposits were persistently present on the sheet surface. In order to improve the surface quality, the sheets were dipped in hydrochloric acid bath for a long time. Hydrochloric acid bath was in aged condition; by that point of time, the bath went through extensive usage for pickling of different grades of steels. Consequently there was significant accumulation of iron salts in the bath. It is known that ferric and chloride ions cause significant acceleration in pitting. The bath was stagnant and the time of immersion of the sheets in the bath was long. The material failed under the combination of these adverse conditions. The paper brings out the details of the failure analysis carried out.
Effects of Sn and Ca additions on microstructure, mechanical properties, and corrosion resistance of the as‐cast Mg‐Zn‐Al‐based alloy
Authors: Jihua C. , Zhenhua C. , Hongge Y. , Fuquan Z. , Yingliang C.
Published: August 2008

Effects of Sn and Ca additions on microstructure, mechanical properties, and corrosion resistance of the as‐cast Mg‐6Zn‐2Al‐based alloy were investigated by SEM, XRD, tensile tests, electrochemical measurements, etc. The higher the Sn content, the higher the yield strength of the Mg‐6Zn‐2Al‐based alloy. Trace Ca addition refined both grains and divorced eutectics in the Mg‐Zn‐Sn‐Al alloys, leading to the best combination of strength and plasticity. Moreover, its influence was more significant for the alloy with a higher Sn content. Furthermore, the combined addition had a beneficial effect on the corrosion resistance improvement of the Mg‐6Zn‐2Al alloy. The Mg‐6Zn‐2Al‐3Sn‐0.2Ca alloy was the most corrosion‐resistant alloy among the nine alloys studied, better than AZ91 and ZA85. It could be ascribed to the decrease and the refinement of divorced eutectics, the higher hydrogen overvoltage of Sn and the Ca grain refinement.
Corrosion behavior of Ti‐xNb‐13Zr alloys in Ringer's solution
Authors: Robin A. , Carvalho O. A. S. , Schneider S. G. , Schneider S.
Published: August 2008

Ti‐6Al‐4V alloy has been widely used in restorative surgery due to its high corrosion resistance and biocompatibility. Nevertheless, some studies showed that V and Al release in the organism might induce cytotoxic effects and neurological disorders, which led to the development of V‐free alloys and both V‐ and Al‐free alloys containing Nb, Zr, Ta, or Mo. Among these alloys, Ti‐13Nb‐13Zr alloy is promising due to its better biomechanical compatibility than Ti‐6Al‐4V. In this work, the corrosion behavior of Ti, Ti‐6Al‐4V, and Ti‐xNb‐13Zr alloys (x = 5, 13, and 20) was evaluated in Ringer's solution (pH 7.5) at 37 °C through open‐circuit potential measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy. Spontaneous passivity was observed for all materials in this medium. Low corrosion current densities (in the order of 10−7 A/cm2) and high impedance values (in the order of 105 Ωcm2 at low frequencies) indicated their high corrosion resistance. EIS results showed that the passivating films were constituted of an outer porous layer (very low resistance) and an inner compact layer (high resistance), the latter providing the corrosion resistance of the materials. There was evidence that the Ti‐xNb‐13Zr alloys were more corrosion resistant than both Ti and Ti‐6Al‐4V in Ringer's solution.
The Free Volume and Its Recovery in Pressure‐Densified and CO2‐Swollen Heterocyclic‐Ring‐Containing Fluoropolymers
Authors: Dlubek Günter , Pionteck Jürgen , Yu Yang , Thränert Stefan , Elsayed Mohamed , Badawi Emad , Krause‐Rehberg Reinhard
Published: August 2008

Changes in the free volume in CYTOP due to pressure densification and swelling with CO2 have been examined using PALS and PVT experiments. Employing the Simha‐Somcynsky equation of state the specific hole free, Vf, and occupied, Vocc, volumes were estimated. The change in the total volume due to the pre‐treatments occurs exclusively in the hole free volume and the relative change in Vf is one order of magnitude larger than in the total volume. Vocc shows no memory for the history of the polymer glass. The mean and width of the size distribution of subnanometre holes in the glassy state decrease upon densification and increase upon swelling. The volume changes which are frozen in the polymer glass begin to recover at temperatures distinctly below Tg.

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Multifunctional Polymethacrylates Obtained Via ATRP of Functional and Reactive Monomers Followed by Polymer Analogous Reaction with Functional Amines
Authors: Popescu Dragos , Keul Helmut , Moeller Martin
Published: August 2008

Starting from methyl methacrylate (MMA), butyl methacrylate (BMA), allyl methacrylate (AMA), phenoxycarbonyloxy ethyl methacrylate (PCEMA), and functional amines different multifunctional polymethacrylates are accessible. The reactive monomer PCEMA was synthesized starting from 2‐hydroxyethyl methacrylate, and then copolymerized via ATRP with other methacrylates in order to obtain reactive copolymers which were subjected to polymer analogous reactions with different functional amines leading to multifunctional polymethacrylates. These can be used for the preparation of multifunctional surfaces.

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Macromol. Mater. Eng. 8/2008
Authors: Acharya Manoranjan , Arumugam Ganesh Kumar , Heiden Patricia A.
Published: August 2008

Cover: The cover picture shows an electrospinning set‐up having a second electric field applied perpendicular to the primary electric field. This is done in order to compress the bending pathway in one direction to assist alignment of the electrospun fiber as it deposits onto a collector. A digital photograph shows electrospun PLLA fiber collected onto a parallel electrodes collector, and a Fourier Transform image shows the quality of the alignment. Further details can be found in the article by M. Acharya, G. K. Arumugam,* and P. A. Heiden* on page 666.
Improved PEDOT Conductivity via Suppression of Crystallite Formation in Fe(III) Tosylate During Vapor Phase Polymerization
Authors: Zuber Kamil , Fabretto Manrico , Hall Colin , Murphy Peter
Published: August 2008

Vapor phase polymerization was used to synthesize high conductivity poly(3,4‐ethylenedioxyphenylene) (PEDOT). The monomer is presented to an oxidant‐rich substrate in vapor form and even for short polymerization times, 10–30 min, Fe(III) tosylate has a propensity for water absorption leading to crystal formation. Poor oxidant treatment before polymerization or high humidity during polymerization can create holes in the PEDOT film decreasing its conductivity. The addition of an amphiphilic copolymer poly(ethylene glycol)‐ran‐poly(propylene glycol) suppresses crystal growth allowing better film formation. The humidity level during synthesis was optimized at 35% relative humidity (RH), producing a conductivity of 761 S · cm−1. Additionally, the copolymer extends the RH range that is tolerable for polymer synthesis.

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Nicotine and Parkinson's disease: Implications for therapy
Authors: Quik Maryka , O'Leary Kathryn , Tanner Caroline M.
Published: August 2008

Accumulating evidence suggests that nicotine, a drug that stimulates nicotinic acetylcholine receptors, may be of therapeutic value in Parkinson's disease. Beneficial effects may be several‐fold. One of these is a protective action against nigrostriatal damage. This possibility stems from the results of epidemiological studies that consistently demonstrate an inverse correlation between tobacco use and Parkinson's disease. This reduced incidence of Parkinson's disease has been attributed to the nicotine in tobacco products, at least in part, based on experimental work showing a protective effect of nicotine against toxic insults. Second, several studies suggest a symptomatic effect of nicotine in Parkinson's disease, although effects are small and somewhat variable. Third, recent data in nonhuman primates show that nicotine attenuates levodopa‐induced dyskinesias, a debilitating side effect that develops in the majority of patients on levodopa therapy. Collectively, these observations suggest that nicotine or CNS selective nicotinic receptor ligands hold promise for Parkinson's disease therapy to reduce disease progression, improve symptoms, and/or decrease levodopa‐induced dyskinesias. © 2007 Movement Disorder Society
Electrogenerated chemiluminescence of benzo 15‐crown‐5 derivatives
Authors: Jiang Xiao , Yang Xichuan , Zhao Changzhi , Sun Licheng
Published: August 2008

Novel electrogenerated chemiluminescence (ECL) reagents C1, C2, and C3 with high fluorescence quantum yields bearing 15‐crown‐5 moiety have been synthesized and characterized. The photophysical, electrochemical, and ECL characters of these compounds have been studied in a 1:1 (v/v) PhH/MeCN mixed solvent. The ECL intensity is enhanced distinctly with the increase in the fluorescence quantum yield. Their ECL behaviors have been studied using annihilation and co‐reactant methods (tri‐n‐propylamine (TPrA) was used as a co‐reactant), respectively. The stable ECL emissions of compounds C1–C3 can be ascribed to the typical and simple monomer ECL emission via S‐route. Copyright © 2008 John Wiley & Sons, Ltd.
Economic‐statistical design of 2‐of‐2 and 2‐of‐3 runs rule scheme
Authors: Kim Young‐Bok , Hong Jung‐Sik , Lie Chang‐Hoon
Published: August 2008

In this paper, we investigate the economic‐statistical design method for the 2‐of‐2 runs rule and the 2‐of‐3 runs rule. The Markov chain approach is used to obtain the average run length and the process cycle time. In addition, a simplified algorithm is presented to search the optimal setting of the design parameters. A numerical example and sensitivity analysis are also provided to compare the performances of the runs rules. The results show that the use of runs rule scheme can reduce operating cost comparing with the Shewhart control chart while maintaining a good statistical performance. Copyright © 2008 John Wiley & Sons, Ltd.
Successful Salvage of Mucormycosis Infection of the Forearm and Osteomyelitis of the Ulna
Authors: Jones Neil F. , Shin Eon K. , Eo SuRak , Starzl Thomas E.
Published: August 2008

A 6-month-old child developed cutaneous mucormycosis of the forearm 5 weeks after liver transplantation, which progressed to osteomyelitis of the proximal ulna. Aggressive treatment, which included serial radical debridements, intravenous administration of amphotericin B, and eventually split thickness skin graft coverage resulted in successful functional salvage of the forearm, wrist, and hand. Of the nine previously reported cases of mucormycosis affecting the forearm or hand in immunocompromised patients, all either required amputation of the hand or below elbow amputation, or resulted in the patient's death. Definitive early diagnosis and serial radical debridements may allow salvage of a functional hand.
A bio-psycho-social model of successful aging as shown through the variable “physical activity”
Authors: Kanning Martina , Schlicht Wolfgang
Published: August 2008

In this article, we present and explain a bio-psycho-social model of successful aging with subjective well-being as a criterion of a successful aging process. We focus on physical activity because it is a crucial behavior. Physical activity can support successful aging in two different ways: first, due to its physiological and cognitive effects, and Second, an older person can enhance subjective well-being (SWB) while being physically active. The model points out that an older person can regulate SWB. To do this, an older person should set and pursue personally and culturally valued goals. The strength of the association between setting a goal and goal pursuance, respectively, and SWB depends on the extent a person is able to satisfy psychological needs (autonomy, competence, relatedness). But, the decision as to which goal will be set and pursued does not belong to the older person exclusively. The bio-psycho-social model explains that the chance to enhance SWB is restricted by personal dispositions (e.g., physiological constitution, psychological factors) and social–structural constraints (e.g., predominant stereotype of aging, facilities especially for target groups).
Role of neonatal hyperleptinaemia on serum adiponectin and suppressor of cytokine signalling-3 expression in young rats
Authors: Passos Magna Cottini Fonseca , Toste Fabiane Pereira , Dutra Sheila Cristina Potente , Trotta Paula Affonso , Toste Fernanda Pereira , Lisboa Patrícia Cristina , de Moura Egberto Gaspar
Published: August 2008

Previously we had shown that neonatal leptin treatment programmes for both hyperleptinaemia and hyperinsulinaemia, which lead to leptin resistance and low expression of the hypothalamic leptin receptor (OB-Rb) of rats aged 150 d. Here we investigated in young post-weaned rats (age 30 d) if leptin treatment during lactation induces leptin and insulin resistance and if those changes are accompanied by changes in the suppressor of cytokine signalling-3 (SOCS-3) expression and serum adiponectin concentration. After delivery, the pups were divided into two groups: (1) a leptin group (Lep) that were injected with leptin daily (8 μg/100 g body weight subcutaneously) for the first 10 d of lactation; (2) a control (C) group, receiving saline. After weaning (day 21), body weight was monitored until the animals were age 30 d. They were tested for food intake in response to either leptin (0·5 mg/kg body weight intraperitoneally) (CL, LepL) or saline (CSal, LepSal) when they were aged 30 d. The CL group showed lower food intake, but no response was observed in the LepL group, suggesting leptin resistance. The Lep group had hyperleptinaemia (five-fold), hyperinsulinaemia (+42·5 %) and lower levels of serum adiponectin ( − 43·2 %). The hypothalamic expression of OB-Rb was lower ( − 22 %) and SOCS-3 was higher (+52·8 %) in the Lep group. We conclude that neonatal leptin treatment programmes for leptin resistance as soon as 30 d and suggests that SOCS-3 appears to be of particular importance in this event. In the Lep group, the lower serum adiponectin levels were accompanied by higher serum insulin, indicating a probable insulin resistance.
Moderate-to-vigorous physical activity and sedentary behaviours in relation to body mass index-defined and waist circumference-defined obesity
Authors: Stamatakis Emmanuel , Hirani Vasant , Rennie Kirsten
Published: August 2008

The aim of the present study was to investigate the relationships of physical activity types and sedentary behaviour with BMI and waist circumference (WC). The sample comprised 6215 adults (2775 men, 3440 women) aged 16 years and over living in Scotland. Self-reported physical activity of moderate to vigorous intensity (MVIA) included domestic activity, walking, and sports and exercises. MVIA levels were classified as being inactive, being insufficiently active, being sufficiently active for general health benefits and being sufficiently active for obesity prevention. Sedentary time was defined as television and other screen-based entertainment time (TVSE). Dependent variables were BMI-defined obesity (BMI-OB) and WC-defined obesity (WC-OB). TVSE was positively related to both WC-OB (adjusted OR 1·69 (95 % CI 1·39, 2·05) for ≥ 4 h of TVSE per d compared with < 2 h/d) and BMI-OB (OR 1·88; 95 % CI 1·51, 2·35) independently of MVIA. Those classified as most active who reported ≥ 4 h/d of TVSE had higher prevalence of BMI-OB (18·9 v. 8·3 %; P < 0·05) and WC-OB (28·0 v. 10·0 %; P < 0·01) than those equally active with < 2 h/d of TVSE. Sports and walking were related inversely to WC-OB (OR for no time compared with ≥ 30 min/d: 1·55 (95 % CI 1·24, 1·94); 2·06 (95 % CI 1·64, 2·58)), but only walking was related to BMI-OB (OR 1·94; 95 % CI 1·58, 2·37). Domestic physical activity was not related to BMI-OB or WC-OB. In conclusion, physical activity and sedentary behaviour are independently related to obesity. Public health recommendations should both promote physical activity and discourage engagement in sedentary pursuits.
Effect of intragastric acid stability of fat emulsions on gastric emptying, plasma lipid profile and postprandial satiety
Authors: Marciani Luca , Faulks Richard , Wickham Martin S. J. , Bush Debbie , Pick Barbara , Wright Jeff , Cox Eleanor F. , Fillery-Travis Annette , Gowland Penny A. , Spiller Robin C.
Published: August 2008

Fat is often included in common foods as an emulsion of dispersed oil droplets to enhance the organoleptic quality and stability. The intragastric acid stability of emulsified fat may impact on gastric emptying, satiety and plasma lipid absorption. The aim of the present study was to investigate whether, compared with an acid-unstable emulsion, an acid-stable fat emulsion would empty from the stomach more slowly, cause more rapid plasma lipid absorption and cause greater satiety. Eleven healthy male volunteers received on two separate occasions 500 ml of 15 % (w/w) [13C]palmitate-enriched olive oil-in-water emulsion meals which were either stable or unstable in the acid gastric environment. MRI was used to measure gastric emptying and the intragastric oil fraction of the meals. Blood sampling was used to measure plasma lipids and visual analogue scales were used to assess satiety. The acid-unstable fat emulsion broke and rapidly layered in the stomach. Gastric emptying of meal volume was slower for the acid-stable fat emulsion (P < 0·0001; two-way ANOVA). The rate of energy delivery of fat from the stomach to the duodenum was not different up to t = 110 min. The acid-stable emulsion induced increased fullness (P < 0·05), decreased hunger (P < 0·0002), decreased appetite (P < 0·0001) and increased the concentration of palmitic acid tracer in the chylomicron fraction (P < 0·04). This shows that it is possible to delay gastric emptying and increase satiety by stabilising the intragastric distribution of fat emulsions against the gastric acid environment. This could have implications for the design of novel foods.
Reproducibility of energy intake, gastric emptying, blood glucose, plasma insulin and cholecystokinin responses in healthy young males
Authors: Nair Nivasinee S. , Brennan Ixchel M. , Little Tanya J. , Gentilcore Diana , Hausken Trygve , Jones Karen L. , Wishart Judith M. , Horowitz Michael , Feinle-Bisset Christine
Published: August 2008

Gastric emptying, as well as intragastric meal distribution, and gastrointestinal hormones, including cholecystokinin (CCK), play an important role in appetite regulation. The evaluation of gastrointestinal factors regulating food intake is commonly performed in healthy, lean, young male participants. It has, however, been suggested that there is a marked interindividual variability in the effects of nutrient ‘preloads’ on energy intake in this group. Whether there is significant intraindividual variation in acute energy intake after a nutrient preload, and, if so, how this relates to day-to-day differences in gastric emptying and gastrointestinal hormone release, is unclear. The purpose of the present paper is to evaluate the hypothesis that energy intake after a nutrient preload would be reproducible and associated with reproducible patterns of gastric emptying, intragastric distribution and gastrointestinal hormone release. Fifteen healthy men (age 25 (sem5) years) consumed a glucose preload (50 g glucose in 300 ml water; 815 kJ) on three occasions. Gastric emptying and intragastric meal distribution (using three-dimensional ultrasound), blood glucose, plasma insulin and CCK concentrations and appetite perceptions were evaluated over 90 min, and energy intake from a cold buffet-style meal was then quantified. Energy intake was highly reproducible within individuals between visits (intraclass correlation coefficient,ri = 0·9). Gastric emptying, intragastric meal distribution, blood glucose, plasma insulin and CCK concentrations and appetite perceptions did not differ between visits (ri>0·7 for all). In healthy males, energy intake is highly reproducible, at least in the short term, and is associated with reproducible patterns of gastric emptying, glycaemia, insulinaemia and CCK release.
Hospitality and the Ethics of Improvisation in the Work of Ingemar Lindh
Authors: Camilleri Frank
Published: August 2008

Ingemar Lindh's work on the principles of collective improvisation has crucial implications for the history of twentieth-century laboratory theatre. His early work with Étienne Decroux and Jerzy Grotowski contributed to the development of a unique practice that resists directorial montage, fixed scores, and choreography; and the ethical dimension that accompanies Lindh's research on collective improvisation is illuminating for a more holistic understanding of the technical and aesthetic considerations in theatre. In this article, Frank Camilleri discusses some of the key aspects of this dimension, notably the dynamics of hospitality and encounter that inform Lindh's approach and the question of responsibility in the actor's work. Frank Camilleri is Lecturer in Drama and Theatre Studies at the University of Kent. From 2004 to 2008 he was Academic Coordinator of Theatre Studies at the University of Malta. He is also Artistic Director of Icarus Performance Project – an ongoing research laboratory that investigates the intermediary space between training and performance processes. Camilleri's work with Lindh in the mid-1990s was instrumental for the development of this research practice.
As Long as the Punters Enjoy It
Authors: Gupta Tanika
Published: August 2008

Tanika Gupta is one of the most prolific and outstanding new writers in contemporary British theatre. Born in Chiswick in 1965, she is a bilingual British Bengali who – after reading modern history at Oxford University – began her career in 1991, when her Radio 4 play, Asha, was part of the BBC Young Playwrights Festival. In 1995, her BBC film, The Rhythm of Raz, was nominated for a Children's BAFTA and the following year her film Bideshi won an award at the Bombay Short Film Festival. Meanwhile, although she made a living writing for Grange Hill and EastEnders, her play Voices on the Wind was being developed and, in 1996–98, she was Writer-in-Residence at the Soho Theatre. In 1997, A River Sutra was staged at Three Mills Island, London, and Skeleton at the Soho Theatre. In 1998, Flight, her BBC2 screenplay, won an EMMA. The Waiting Room (2000), staged by the National, won the John Whiting Award, and was followed by Sanctuary (National) and Inside Out, toured by Clean Break (both 2002). In 2003, Gupta's Fragile Land opened the new Hampstead Theatre's education space, her Asian version of Hobson's Choice was staged at the Young Vic, and she won the Asian Woman of Achievement Award. Later, she had further success with her campaigning play about the Zahid Mubarek case, Gladiator Games (Sheffield Crucible, 2005), and Sugar Mummies (Royal Court, 2006). A year later came a play for the National Youth Theatre, White Boy (Soho). What follows is an edited transcript of Aleks Sierz's ‘In Conversation with Tanika Gupta’, part of the ‘Universal Voices’ festival held at Rose Bruford College, Sidcup, Kent, in April 2007, organized by Nesta Jones.
Deviants and Outcasts: Power and Politics in Hausa Bori Performances
Authors: Okagbue Osita
Published: August 2008

The jihad of Uthman dan Fodio in the early ninteenth century had by 1806 established Islamic cultural and religious hegemony over the Hausa territory of present-day Northern Nigeria. In the process, Islam had succeeded in pushing indigenous religious and cultural practices such as Bori to the margins or underground. However, while most of the other indigenous forms died or became inactive and ineffectual, Bori has managed to hold its own against the persecution and cultural war waged against it by Islam, mainly because the belief in the power and ability of the spirits to influence human life which is at the centre of Bori practice was never lost. In this article, Osita Okagbue argues that marginalization has made Bori attractive to groups and individuals in Hausa society who feel themselves similarly marginalized and oppressed for articulating alternative identities and viewpoints to those of the mainstream society. He also examines how the possession performances of the Bori cult enable members to subvert and occasionally to use moments of trance and possession to invert the power relationships between oppressed groups and their oppressors. Osita Okagbue teaches at Goldsmiths, University of London, and is the author of African Theatres and Performances (Routledge, 2007). He is President of the African Theatre Association (AfTA) and editor of African Performance Review.
Are repetitive particle injections during high‐speed solar wind streams classic substorms?
Authors: Kim Hee‐Jeong , Lee D.‐Y. , Lyons L. R.
Published: August 2008

The relation between substorm occurrences, energetic particle injections, and High‐Intensity Long‐Duration Continuous AE Activity (HILDCAA) events has been an issue. To understand their relationship, we use global auroral images from the Wideband Imaging Camera (WIC) on the Imager for Magnetopause‐to‐Aurora Global Exploration (IMAGE) spacecraft to investigate auroral activity near the times of repetitive particle injections that occur every ∼0.5 to 4 h during HILDCAA events. For the examined HILDCAA intervals during January–July 2003, we identified a total of 481 injection events. Good WIC imaging was available for 121 of these and showed substorm onset brightenings for a significant fraction of the 121 injections. Specifically, excluding 16 injections with ambiguous timings owing to the lack of a near‐midnight spacecraft, we find that 93 of 105 injections (∼88%) occurred within ±5 min of a substorm auroral onset. If we include cases with up to 10‐min timing difference, the percentage becomes 97%. These results indicate that a significant fraction of HILDCAA‐time repetitive particle injections are substorm‐associated and thus suggest that substorms are a major component of HILDCAA geomagnetic activity and a possible contributor to the sustained small negative Dst during these periods.
Mechanisms controlling the diurnal solar tide: Analysis using a GCM and a linear model
Authors: Achatz U. , Grieger N. , Schmidt H.
Published: August 2008

A general circulation model (GCM, HAMMONIA) and a linear model are used for analyzing the dynamics of the total diurnal solar tide in the mesosphere and lower thermosphere, comprising both the migrating and all nonmigrating components. A comparison between this tide in the GCM and in published observations is relatively favorable. The linear model uses monthly means from the GCM as background atmosphere and the diurnal heating rates from that model as forcing. The background atmosphere may be longitude‐dependent so that stationary planetary waves can be included. A straightforward analysis of corresponding effects is thus facilitated. To a large degree the seasonal variability of the diurnal tide is due to variations in the background atmosphere. In addition to corresponding previous results on the impact of the zonal mean atmosphere on the migrating tide, the thermospheric tide is shown to be strongly influenced by the variability of the absorption of solar radiation by O2. With regard to the nonmigrating tidal components, also, their most important forcing mechanisms are tropospheric as for the migrating tide below the thermosphere and their seasonal cycle is mostly controlled by variations of the background atmosphere. In the dynamics of these components, however, the planetary waves take an active role. They can cause reductions in the tidal amplitude by destructive interference with the directly forced nonmigrating tide, as for DS0 in February. The opposite effect of enhancing the tidal amplitude is also observed for DW2 in the same season. The component DE3 is controlled by an interplay between the variability of the zonal mean background and diurnal heating. The correct simulation of a meridional wind amplitude minimum in this tide during NH summer May–August seems to depend critically on the phase relation between the two.
Influences of the Juan de Fuca Eddy on circulation, nutrients, and phytoplankton production in the northern California Current System
Authors: MacFadyen A. , Hickey B. M. , Cochlan W. P.
Published: August 2008

A diagnostic circulation model and water mass analyses are used to examine variability in the structure and circulation of the Juan de Fuca Eddy, a highly productive region at the northern end of the California Current. Results from three years of field studies demonstrate that the eddy increases in spatial extent from early to late summer as the vertically averaged contribution of California Undercurrent source water grows from ∼60% in June to ∼80% in September. Typical near‐surface eddy radii range from ∼15 km in the early summer to ∼30 km in September and increase with depth. Below 100 m, eddy radii are ∼40 km. Fresher water, associated with the estuarine outflow from the Juan de Fuca Strait, is advected around the eddy margin. During southward wind conditions, the combination of cyclonic geostrophic flow and wind‐driven currents in the surface Ekman layer cause the eddy to be “leaky” on its southern perimeter. Eddy surface circulation becomes more retentive (up to ∼32 d observed) during periods of weak winds or frequent northward reversals. The presence of the eddy facilitates large inputs of dissolved inorganic nutrients into the region through two mechanisms: doming of California Undercurrent water within the eddy and enhanced cross‐shelf advection of Juan de Fuca Strait outflow. The combination of these sources results in a persistent, broad (100 km offshore) region of elevated macronutrients. The retentive circulation patterns combined with persistent nutrient supply may favor the development of toxigenic diatom blooms of Pseudo‐nitzschia species in this region.
Performance of DEMETER calibration for rainfall forecasting purposes: Application to the July–August Sahelian rainfall
Authors: Bouali Lotfi , Philippon Nathalie , Fontaine Bernard , Lemond Julien
Published: August 2008

This work assesses and compares the skill of direct and model‐output‐statistics (MOS) calibrated hindcasts of the July–August rainfall amounts for the dry period 1980–2000 over the Sahel issued from the Development of a European Multimodel Ensemble System for Seasonal to Interannual Prediction (DEMETER) experiment, with the aim to highlight among the simulated parameters, i.e., those potentially relevant for rainfall forecasts purposes. Three approaches were used: the DEMETER (1) direct rainfall, (2) MOS‐calibrated rainfall, and (3) MOS‐calibrated atmospheric dynamics and energy. Canonical correlation analyses (CCA) were employed in the two latter approaches to calibrate the direct rainfall fields from DEMETER. The main results are the following. First, the observed relationship between indexes depicting Sahelian rainfall (SRI) and West African Monsoon dynamics (MOD850 for the modulus of the wind at 850 hPa) is not correctly reproduced in DEMETER: the correlation between them achieves 0.25 only (versus 0.6 in observations). The calibration with atmospheric dynamics and energy fields (moist static energy fluxes at 850 hPa and zonal wind at 500 hPa) leads to slightly higher results than with rainfall. Second, the leading coupled mode of the CCA between observed rainfall and simulated atmospheric dynamics (∼28% of the total variance) connects Sahelian rainfall variability to a weakened African Easterly Jet (AEJ, somewhat shifted to the north) as well as to the strength of the MSE fluxes from the Guinean Gulf and the Mediterranean Sea. Finally, the teleconnection pattern between the CCA mode and simulated surface temperatures concurs well with observations, giving confidence into the physical basis of the mode, although the cross‐validated skill scores obtained through the three approaches remain low.
Aircraft measurements of the impacts of pollution aerosols on clouds and precipitation over the Sierra Nevada
Authors: Rosenfeld Daniel , Woodley William L. , Axisa Duncan , Freud Eyal , Hudson James G. , Givati Amir
Published: August 2008

Recent publications suggest that anthropogenic aerosols suppress orographic precipitation in California and elsewhere. A field campaign (SUPRECIP: Suppression of Precipitation) was conducted to investigate this hypothesized aerosol effect. The campaign consisted of in situ aircraft measurements of the polluting aerosols, the composition of the clouds ingesting them, and the way the precipitation‐forming processes are affected. SUPRECIP was conducted during February and March of 2005 and February and March of 2006. The flights documented the aerosols and orographic clouds flowing into the central Sierra Nevada from the upwind densely populated industrialized/urbanized areas and contrasted them with the aerosols and clouds downwind of the sparsely populated areas in the northern Sierra Nevada. SUPRECIP found that the aerosols transported from the coastal regions are augmented greatly by local sources in the Central Valley resulting in high concentrations of aerosols in the eastern parts of the Central Valley and the Sierra foothills. This pattern is consistent with the detected patterns of suppressed orographic precipitation, occurring primarily in the southern and central Sierra Nevada, but not in the north. The precipitation suppression occurs mainly in the orographic clouds that are triggered from the boundary layer over the foothills and propagate over the mountains. The elevated orographic clouds that form at the crest are minimally affected. The clouds are affected mainly during the second half of the day and the subsequent evening, when solar heating mixes the boundary layer up to cloud bases. Local, yet unidentified nonurban sources are suspected to play a major role.
Correlative study of plasma bubbles, evening equatorial ionization anomaly, and equatorial prereversal E × B drifts at solar maximum
Authors: Li Guozhu , Ning Baiqi , Liu Libo , Zhao Biqiang , Yue Xinan , Su S.‐Y. , Venkatraman Sarita
Published: August 2008

Previous ground observations have revealed a correlation that exists between equatorial plasma bubbles, evening equatorial ionization anomaly (EIA), and prereversal E × B drift velocity using latitudinal arrays of ionospheric sounders, such as in the Indian and American regions. Besides the ground measurements, the space‐based observations also provide a convenient way to study the global‐scale variations. On the basis of in situ data collected from DMSP, ROCSAT‐1, and CHAMP satellites, we investigated the correlation of seasonal/longitudinal variations of plasma bubble (PB) occurrence, evening EIA, and prereversal E × B drifts on magnetically quiet days during the solar maximum years (2000–2002). In general, the observational results provide consistent evidences that the large‐scale variations in seasonal/longitudinal distribution of evening EIA and PB occurrence rates are well‐correlated with the observed evening prereversal E × B drifts and that some of the small‐scale longitudinal variations (such as wave number‐4 structure during equinox) of evening EIA exist before the occurrence of the prereversal enhancement and coincide with the daytime equatorial electrojet. In such cases, the small‐scale longitudinal variation of PB occurrence rates may result from the evening EIA small‐scale longitudinal structures. The evening prereversal E × B drifts, together with the longitudinal variations of evening EIA, are assumed to play a role in determining the longitudinal variations of equatorial and low‐latitude PB occurrence rates.