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Terms modified by Several Times Selected AbstractsTotal body exposure to ultraviolet radiation does not influence plasma levels of immunoreactive ,-endorphin in manPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 6 2001Marjolein Wintzen Background/Aims: A growing number of reports support evidence of proopiomelanocortin (POMC)-derived peptides in human skin cells, although not consistently. Also the effect of ultraviolet radiation (UVR) on cutaneous and plasma levels of these POMC peptides has not been established unequivocally. We hypothesized that production of ,-endorphin (,E) may explain the sense of well-being many people experience when sun-bathing. The aim of the present study was to investigate whether exposure of the skin to UVR elevates plasma ,E. Method: Healthy volunteers (n=26) received a single, weighted dose of 15 J/cm2 of UVA. Several times during the hour following irradiation, plasma ,E- immunoreactivity (,E-IR) was determined by radioimmunoassay. The effect of repeated exposure wasassessed in 35 patients treated with UVB, UVA, or UVA-1. Plasma ACTH-IR was monitored in parallel. Results: Overall, plasma levels of ,E-IR and ACTH-IR showed no significant changes during the experiment, indicating that these peptides are not influenced by single or repeated exposures to UVR of different wavelengths. Conclusion: On the basis of these results, the skin does not appear to contribute significantly to the levels of circulating ,E or ACTH. These data offer no support for the hypothesis that exposure to UVR leads to an increased concentration of circulating ,E, which could contribute to the feeling of well-being that often accompanies sun-bathing. [source] FISCAL FEDERALISM, STATE LOBBYING AND DISCRETIONARY FINANCE: EVIDENCE FROM INDIAECONOMICS & POLITICS, Issue 1 2010RONGILI BISWAS In the quasi-federal democratic polity that India has, lobbying for central funds by the states is often done in a subliminal fashion. Hence, it becomes difficult to get an account of how much lobbying has been done to a particular end. Our paper attempts at constructing certain political proxy variables to quantify the extent of such lobbying in India. We quantify lobbying through the ministerial representation in the council of ministers. We also use several time and state dummies to account for the constituent states' political alignment with the center as well as the coalition and the reform period breaks in the Indian system. Taking panel data that cover 29 years and 14 major states we show that our constructed variables do explain disparity in central fiscal disbursements under the non-formulaic "discretionary" head in a robust way. Our findings remain true even after we take into account the impact of endogeneity of net state income on the transfers. Additionally, our exercise brings to the fore the fact that the coalition governments and economic reform measures impact upon state lobbying at the center in a significant manner. [source] Non-pigmenting fixed drug eruption caused by allylisopropylacetylureaCONTACT DERMATITIS, Issue 4 2003Yukikazu Numata An unusual case of a non-pigmenting fixed drug eruption caused by allylisopropylacetylurea is reported. Several hours after taking an analgesic (New Kaiteki A®), a 30-year-old Japanese woman, who had experienced similar eruptions several times after taking other analgesics, developed numerous variously sized, itchy, round-to-oval erythematous eruptions on the trunk and extremities. After she discontinued taking this drug, all such eruptions resolved within 2 weeks, without leaving postinflammatory pigmentation. Patch testing with New Kaiteki A® itself and one of its active ingredients, allylisopropylacetylurea, on lesional skin, but not on uninvolved skin, showed positive erythematous reactions after 2 days. [source] High speed sliding of axonemal microtubules produced by outer arm dyneinCYTOSKELETON, Issue 2 2005Raviraja N. Seetharam Abstract To study dynein arm activity at high temporal resolution, axonemal sliding was measured field by field for wild type and dynein arm mutants of Tetrahymena thermophila. For wt SB255 cells, when the rate of data acquisition was 60 fps, about 5× greater than previously published observations, sliding was observed to be discontinuous with very high velocity sliding (average 196 ,m/sec) for a few msec (1 or 2 fields) followed by a pause of several fields. The sliding velocities measured were an order of magnitude greater than rates previously measured by video analysis. However, when the data were analyzed at 12 fps for the same axonemes, consistent with previous observations, sliding was linear as the axonemes extended several times their original length with an average velocity of ,10 ,m/sec. The pauses or stops occurred at approximately 200 and 300% of the initial length, suggesting that dynein arms on one axonemal doublet were initially active to the limit of extension, and then the arms on the next doublet became activated. In contrast, in a mutant where OADs are missing, sliding observed at 60 fps was continuous and slow (5 ,m/sec), as opposed to the discontinuous high-velocity sliding of SB255 and of the mutant at the permissive temperature where OADs are present. High-velocity step-wise sliding was also present in axonemes from an inner arm dynein mutant (KO6). These results indicate that the high-speed discontinuous pattern of sliding is produced by the mechanochemical activity of outer arm dynein. The rate of sliding is consistent with a low duty ratio of the outer arm dynein and with the operation of each arm along a doublet once per beat. Cell Motil. Cytoskeleton 60:96,103, 2005. © 2004 Wiley-Liss, Inc. [source] Maladaptation to mental stress mitigated by the adaptive immune system via depletion of naturally occurring regulatory CD4+CD25+ cellsDEVELOPMENTAL NEUROBIOLOGY, Issue 6 2006Hagit Cohen Abstract Peripheral cellular immunity was recently shown to play a critical role in brain plasticity and performance. The antigenic specificity of the participating T cells, however, was not investigated, and nor was their relevance to psychological stress. Here we show, using a mouse model, that adaptive immunity mitigates maladaptation to the acute psychological stress known to trigger abnormal behaviors reminiscent of human post-traumatic stress disorder. Assessment of behavioral adaptation (measured by the acoustic startle response and avoidance behavior) in mice after their exposure to predator odor revealed that maladaptation was several times more prevalent in T cell-deficient mice than in their wild-type counterparts. A single population of T cells reactive to central nervous system (CNS)-associated self-protein was sufficient to endow immune-deficient mice with the ability to withstand the psychological stress. Naturally occurring CD4+CD25+ regulatory T cells were found to suppress this endogenous anti-stress attribute. These findings suggest that T cells specific to abundantly expressed CNS antigens are responsible for brain tissue homeostasis and help the individual to cope with stressful life episodes. They might also point the way to development of immune-based therapies for mental disorders, based either on up-regulation of T cells that partially cross-react with self-antigens or on weakening of the activity of regulatory T cells. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] The relationship between host selection behaviour and offspring fitness in a koinobiont parasitoidECOLOGICAL ENTOMOLOGY, Issue 4 2000Ana Rivero Summary 1. When host quality varies, optimal foraging theory assumes that parasitic wasps select hosts in a manner that increases their individual fitness. In koinobiont parasitoids, where the hosts continue developing for a certain period of time after parasitisation, host selection may not reflect current host quality but may be based on an assessment of future growth rates and resources available for the developing larvae. 2. When presented with hosts of uniform quality, the koinobiont parasitoid Leptomastix dactylopii exhibits a characteristic host-selection behaviour: some hosts are accepted for oviposition on first encounter, while others are rejected several times before an egg is laid in them, a behaviour that is commonly associated with a changing host acceptance threshold during the course of a foraging bout. 3. The fitness of the offspring that emerged from hosts accepted immediately upon encounter was compared with the fitness of offspring emerged from hosts rejected several times before being accepted for oviposition. 4. The pattern of host acceptance and rejection was not related to any of the measured fitness parameters of the offspring emerging from these hosts (development time, size at emergence, sex ratio at emergence, and female offspring egg load). 5. While complex post facto adaptive explanations can be devised to explain the nature of such a time and energy consuming host selection process, it is suggested that physiological constraints on egg production or oviposition may provide an alternative, purely mechanistic, explanation for the results obtained. [source] A cooperative distance learning method based on narrow-band Internet and its evaluationELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 4 2010Dilmurat Tilwaldi Abstract This paper describes the experimental evaluation of a cooperative distance learning method, which can be utilized on narrow-band Internet. In this method, students in a group learning environment perform a series of study tasks several times, then create an online report, communicating through a chat facility about a given topic. They try to gain a benefit from their study through a more cooperative attitude. The teacher gives a short lecture at the first stage, and then gives supplementary explanations after ascertaining the degree of understanding by the students at the middle stage of the study. Teaching materials are distributed to the students' PCs beforehand and the lecture can be carried out in a narrow-band environment by transmitting commands. The teacher analyzes the students' communication logs and gives advice for the next study session. This paper describes the result of an evaluation of the proposed method involving a simulated installation of the environment within the campus, which simulated a trial of cooperative distance learning in the periphery of an overseas desert environment. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(4): 36,49, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10139 [source] Oxidative stress biomarkers in bivalves transplanted to the Guadalquivir estuary after Aznalcóllar spillENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2003Antonio Romero-Ruiz Abstract Biological effects of metals were studied in clams (Scrobicularia plana) transplanted to Guadalquivir estuary (Spain) at several times after the spill of toxic metals from Aznalcóllar pyrite mine (southwest Spain) (April 1998) using biochemical biomarkers responsive to reactive oxygen species. Significant As, Cd, Fe, Mn, Ni, and Pb uptake was found in clams living for seven months at the estuary (from July 1999). Increased activity of antioxidant (catalase, glucose-6-phosphate, and 6-phosphogluconate dehydrogenase) and glutathione-related (glutathione reductase and glyoxalase I and II) enzymes was also found after short exposures; the levels of malondialdehyde and metallothionein increased also, particularly with long exposures. Clams living four weeks at the estuary (from March 2000) but not at a reference site also accumulated metals. The higher malondialdehyde and lower reduced-glutathione levels and the more oxidized glutathione status confirmed the oxidative stress of clams living at the estuary, while no marked increase of antioxidant activities was found this time. Lower metal availability along the second transplant could explain the limited responses in this shorter experiment. Although the status of Guadalquivir estuary has recovered since Aznalcóllar spill, continuous monitoring is needed to confirm its progress and to be alert to possible deterioration after heavy rains. [source] The spectrum of benign myoclonus of early infancy: Clinical and neurophysiologic features in 102 patientsEPILEPSIA, Issue 5 2009Roberto H. Caraballo Summary Purpose:, To redefine benign myoclonus of early infancy (BMEI) through analysis of clinical and neurophysiologic features in 102 patients with the aim to widen the spectrum of the syndrome, including a number of different clinical expressions of transient nonepileptic paroxysmal movements occurring in normal infants. Methods:, We recruited patients from one center in Argentina and two in Italy, including infants with normal neurologic and psychomotor development presenting with brief paroxysmal abnormal movements. Children with motor phenomena occurring only during sleep were excluded. Patients with abnormal interictal or ictal electroencephalography (EEG) findings were also excluded. The follow-up ranged from 2,40 years. Results:, One hundred and two infants (60 male) met the inclusion criteria. Age at onset ranged from 1,12 months, with a median age of 6.2 months. The following nonepileptic paroxysmal motor phenomena were recognized: (1) myoclonus, (2) spasms and brief tonic contractions, (3) shuddering, (4) atonia or negative myoclonus, (5) more than one type of motor phenomenon. In the majority of cases the episodes occurred only while awake and repeated several times a day. In 45 (44.1%) of the 102 cases contractions appeared in clusters. Conclusions:, Based on the analysis of clinical and EMG features in this large series of infants, we postulate that the spectrum of the syndrome is wider than initially suspected, and that the different transient motor manifestations and their correlation with different EMG patterns will allow recognition of this definitely benign condition comprising a variety of episodic motor phenomena in normal babies. [source] Incorporation of a (Cyclopentadienyl)molybdenum Oxo Complex in MCM-41 and Its Use as a Catalyst for Olefin EpoxidationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2004Marta Abrantes Abstract The tricarbonyl complex [(,5 -C5H4 -COOMe)Mo(CO)3Cl] was prepared from the reaction of sodium (methoxycarbonyl)cyclopentadienide, (C5H4 -CO2Me)Na, with (Bu4N)[Mo(CO)5I]. Heating the ester with 3-(triethoxysilyl)propylamine gave the amide derivative {[,5 -C5H4 -CONH-C3H6Si(OEt)3]Mo(CO)3Cl}. The functionalised tricarbonyl complex was immobilised in the ordered mesoporous silica MCM-41 with a loading of 13 wt.-% Mo (1.4 mmol·g,1) by carrying out a grafting reaction in dichloromethane. Powder X-ray diffraction and nitrogen adsorption,desorption analysis indicated that the structural integrity of the support was preserved during the grafting and that the channels remained accessible, despite significant reductions in surface area, pore volume and pore size. The success of the coupling reaction was confirmed by 29Si and 13C (CP) MAS NMR spectroscopy. A supported dioxo complex of the type [(,5 -C5H4R)MoO2Cl] was subsequently prepared by oxidative decarbonylation of the tethered tricarbonyl complex using tert -butyl hydroperoxide (TBHP). The oxidised material is an active catalyst for the liquid phase epoxidation of cyclooctene with TBHP as the oxygen source. Similar catalytic results were obtained using the tethered tricarbonyl complex directly as a pre-catalyst since fast oxidative decarbonylation occurs under the reaction conditions used. For both systems, the desired epoxide was the only product and the initial activities were about 13 mol·molMo,1·h,1. The solid catalysts were recycled several times. Some activity was lost between the first and second runs but thereafter tended to stabilise. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis of ,-Amino Nitriles from Carbonyl Compounds, Amines, and Trimethylsilyl Cyanide: Comparison between Catalyst-Free Conditions and the Presence of Tin Ion-Exchanged MontmorilloniteEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 9 2010Jiacheng Wang Abstract In the absence of catalysts, the three-component, one-pot synthesis of ,-amino nitriles proceeded using various aldehydes and ketones together with amines and trimethylsilyl cyanide (TMSCN) in high yields under neat conditions at room temperature. The addition order of the reagents had a significant influence on the yields of the desired ,-amino nitriles. In contrast, when tin ion-exchanged montmorillonite (Sn-Mont), prepared by the ion-exchange of sodium montmorillonite (Na-Mont) with a tin tetrachloride solution, was used as a catalyst, the reaction rates significantly increased compared with those without catalysts, and the range of the applicable carbonyl compounds was also extended: structurally diverse aromatic, aliphatic and heteroatom-containing carbonyl compounds, including sterically hindered ketones as well as aliphatic and aromatic amines, were converted into the desired ,-amino nitriles in good to excellent yields with short reaction times under mild conditions. Sn-Mont showed a better catalytic activity than proton or other metal ion-exchanged montmorillonites, supported SnO2 catalysts and the previously reported homogeneous or heterogeneous catalysts. The recovered catalyst was reused several times without loss of catalytic performance. Along with the expansion of the interlayer space of Sn-Mont, the strong Brřnsted acid and Lewis acid nature of Sn-Mont derived from protons and SnO2 nanoparticles present in the interlayers of Sn-Mont likely played important and cooperative roles in the high catalytic activity. [source] THE PHYLOGENY OF THE PENTASCHISTIS CLADE (DANTHONIOIDEAE, POACEAE) BASED ON CHLOROPLAST DNA, AND THE EVOLUTION AND LOSS OF COMPLEX CHARACTERSEVOLUTION, Issue 4 2007C. Galley We construct a species-level phylogeny for the Pentaschistis clade based on chloroplast DNA, from the following regions: trnL-F, trnT-L, atpB-rbcL, rpL16, and trnD-psbA. The clade comprises 82 species in three genera, Pentaschistis, Pentameris, and Prionanthium. We demonstrate that Prionanthium is nested in Pentaschistis and that this clade is sister to a clade of Pentameris plus Pentaschistis tysonii. Forty-three of the species in the Pentaschistis clade have multicellular glands and we use ancestral character state reconstruction to show that they have been gained twice or possibly once, and lost several times. We suggest that the maintenance, absence, loss, and gain of glands are correlated with leaf anatomy type, and additionally that there is a difference in the degree of diversification of lineages that have these different character combinations. We propose that both glands and sclerophyllous leaves act as defense systems against herbivory, and build a cost/benefit model in which multicellular glands or sclerophyllous leaves are lost when the alternative defense system evolves. We also investigate the association between leaf anatomy type and soil nutrient type on which species grow. There is little phylogenetic constraint in soil nutrient type on members of the Pentaschistis clade, with numerous transitions between oligotrophic and eutrophic soils. However, only orthophyllous-leaved species diversify on eutrophic soils. We suggest that the presence of these glands enables the persistence of orthophyllous lineages and therefore diversification of the Pentaschistis clade on eutrophic as well as oligotrophic soils. [source] Context-aware environments: from specification to implementationEXPERT SYSTEMS, Issue 5 2007Patrick Reignier Abstract: This paper deals with the problem of implementing a context model for a smart environment. The problem has already been addressed several times using many different data- or problem-driven methods. In order to separate the modelling phase from implementation, we first represent the context model by a network of situations. Then, different implementations can be automatically generated from this context model depending on user needs and underlying perceptual components. Two different implementations are proposed in this paper: a deterministic one based on Petri nets and a probabilistic one based on hidden Markov models. Both implementations are illustrated and applied to real-world problems. [source] Site-directed mutagenesis of the active site loop of the rhodanese-like domain of the human molybdopterin synthase sulfurase MOCS3FEBS JOURNAL, Issue 11 2007Major differences in substrate specificity between eukaryotic, bacterial homologs Sequence alignments of human molybdopterin synthase sulfurase, MOCS3, showed that the N-terminal domain is homologous to Escherichia coli MoeB, whereas the C-terminal domain is homologous to rhodanese-like proteins. Previous studies showed that the activity of the separately purified rhodanese-like domain of MOCS3 displayed 1000-fold lower activity in comparison to bovine rhodanese with thiosulfate as sulfur source. When the six amino acid active site loop of MOCS3 rhodanese-like domain was exchanged with the loop found in bovine rhodanese, thiosulfate:cyanide sulfurtransferase activity was increased 165-fold. Site-directed mutagenesis of each individual residue of the active site loop of the MOCS3 rhodanese-like domain showed that the charge of the last amino acid determines thiosulfate sulfurtransferase activity. Replacing Asp417 by threonine resulted in 90-fold increased activity, whereas replacing it by arginine increased the activity 470-fold. Using a fully defined in vitro system containing precursor Z, MOCS2A, E. coli MoaE, E. coli MoeB, Mg-ATP, MOCS3 rhodanese-like domain, and thiosulfate, it was shown that sulfur transfer to MOCS2A was also affected by the alterations, but not as drastically. Our studies revealed that in humans and most eukaryotes thiosulfate is not the physiologic sulfur donor for MOCS3, whereas in bacterial homologs, which have an arginine at the last position of the active site loop, thiosulfate can be used as a sulfur source for molybdenum cofactor biosynthesis. The phylogenetic analysis of MoeB homologs showed that eukaryotic homologs are of bacterial origin. Furthermore, it could be shown that an MoeB homolog named MoeZ, where the dual CXXC zinc-binding motif of the MoeB domain is not present, arose independently several times during evolution. [source] The history of a developmental stage: Metamorphosis in chordatesGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 11 2008Mathilde Paris Abstract Metamorphosis displays a striking diversity in chordates, a deuterostome phylum that comprises vertebrates, urochordates (tunicates), and cephalochordates (amphioxus). In anuran amphibians, the tadpole loses its tail, develops limbs, and undergoes profound changes at the behavioral, physiological, biochemical, and ecological levels. In ascidian tunicates, the tail is lost and the head tissues are drastically remodeled into the adult animal, whereas in amphioxus, the highly asymmetric larva transforms into a relatively symmetric adult. This wide diversity has led to the proposal that metamorphosis evolved several times independently in the different chordate lineages during evolution. However, the molecular mechanisms involved in metamorphosis are largely unknown outside amphibians and teleost fishes, in which metamorphosis is regulated by the thyroid hormones (TH) T3 and T4 binding to their receptors (thyroid hormone receptors). In this review, we compare metamorphosis in chordates and then propose a unifying definition of the larva-to-adult transition, based on the conservation of the role of THs and some of their derivatives as the main regulators of metamorphosis. According to this definition, all chordates (if not, all deuterostomes) have a homologous metamorphosis stage during their postembryonic development. The intensity and the nature of the morphological remodeling varies extensively among taxa, from drastic remodeling like in some ascidians or amphibians to more subtle events, as in mammals. genesis 46:657,672, 2008. © 2008 Wiley-Liss, Inc. [source] Effects of soil frost on soil respiration and its radiocarbon signature in a Norway spruce forest soilGLOBAL CHANGE BIOLOGY, Issue 4 2009JAN MUHR Abstract Apart from a general increase of mean annual air temperature, climate models predict a regional increase of the frequency and intensity of soil frost with possibly strong effects on C cycling of soils. In this study, we induced mild soil frost (up to ,5 °C in a depth of 5 cm below surface) in a Norway spruce forest soil by removing the natural snow cover in the winter of 2005/2006. Soil frost lasted from January to April 2006 and was detected down to 15 cm depth. Soil frost effectively reduced soil respiration in the snow removal plots in comparison to undisturbed control plots. On an annual basis 6.2 t C ha,1 a,1 were emitted in the control plots compared with 5.1 t C ha,1 a,1 in the snow removal plots. Only 14% of this difference was attributed to reduced soil respiration during the soil frost period itself, whereas 63% of this difference originated from differences during the summer of 2006. Radiocarbon (,14C) signature of CO2 revealed a considerable reduction of heterotrophic respiration on the snow removal plots, only partly compensated for by a slight increase of rhizosphere respiration. Similar CO2 concentrations in the uppermost mineral horizons of both treatments indicate that differences between the treatments originated from the organic horizons. Extremely low water contents between June and October of 2006 may have inhibited the recovery of the heterotrophic organisms from the frost period, thereby enhancing the differences between the control and snow removal plots. We conclude that soil frost triggered a change in the composition of the microbial community, leading to an increased sensitivity of heterotrophic respiration to summer drought. A CO2 pulse during thawing, such as described for arable soils several times throughout the literature, with the potential to partly compensate for reduced soil respiration during soil frost, appears to be lacking for this soil. Our results from this experiment indicate that soil frost reduces C emission from forest soils, whereas mild winters may enhance C losses from forest soils. [source] Forage potential of semi-leafless grain peasGRASS & FORAGE SCIENCE, Issue 2 2003J. M. Koivisto Abstract Individually sown plants of a forage-type pea (Pisum sativum L.), cv. Magnus, and a grain-type pea cv. Eiffel, were harvested several times over the growing season to determine how the quantity of plant components changed with time from sowing. There was no difference between the pea types in the mean dry weight per plant. The leaf-to-stem ratio of the two types was also not different. An appropriate grain-type pea cultivar could be a suitable substitute for forage-type cultivar in some forage production systems. [source] The Lisse Effect RevisitedGROUND WATER, Issue 6 2002Edwin P. Weeks The Lisse effect is a rarely noted phenomenon occurring when infiltration caused by intense rain seals the surface soil layer to airflow, trapping air in the unsaturated zone. Compression of air by the advancing front results in a pressure increase that produces a water-level rise in an observation well screened below the water table that is several times as large as the distance penetrated by the wetting front. The effect is triggered by intense rains and results in a very rapid water-level rise, followed by a recession lasting a few days. The Lisse effect was first noted and explained by Thal Larsen in 1932 from water-level observations obtained in a shallow well in the village of Lisse, Holland. The original explanation does not account for the increased air pressure pushing up on the bottom of the wetting front. Analysis of the effect of this upward pressure indicates that a negative pressure head at the base of the wetting front, ,f, analogous to that postulated by Green and Ampt (1911) to explain initially rapid infiltration rates into unsaturated soils, is involved in producing the Lisse effect. Analysis of recorded observations of the Lisse effect by Larsen and others indicates that the water-level rise, which typically ranges from 0.10 to 0.55 m, should be only slightly larger than |,f| and that the depth of penetration of the wetting front is no more than several millimeters. [source] Multicomponent Approach Towards the Synthesis of Substituted Pyrroles under Supramolecular Catalysis Using , -Cyclodextrin as a Catalyst in Water Under Neutral ConditionsHELVETICA CHIMICA ACTA, Issue 10 2009Narayana Murthy, Sabbavarapu Abstract Synthesis of substituted pyrroles in H2O by using , -cyclodextrin as a supramolecular catalyst is described. This reaction has several advantages over existing methods and provides substituted pyrroles in good-to-excellent yields (79,89%). The supramolecular catalysis of the reaction was studied using 1H-NMR spectroscopy. , -Cyclodextrin can be recovered and reused several times without loss of activity. [source] Bulk and supported tungstophosphoric acid as friendly, efficient, recyclable catalysts for the synthesis of bis-indolylmethanes under solvent-free conditionsHETEROATOM CHEMISTRY, Issue 6 2009Hamid Aliyan The treatment of indole with structurally diverse aldehydes in the presence of catalytic amount of inorganic-supported polyoxometalates, heterogeneous, reusable and efficient catalysts at room temperature gave the corresponding bis-indolylmethanes in excellent yields and shorter reaction times under solvent-free conditions. The catalyst can be reused for several times, but it will be less active. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:325,331, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20554 [source] Facile route for the synthesis of benzothiazoles and benzimidazoles in the presence of tungstophosphoric acid impregnated zirconium phosphate under solvent-free conditionsHETEROATOM CHEMISTRY, Issue 4 2009Hamid Aliyan Rapid and efficient condensation reactions of o -phenylenediamine and o -aminothiophenol with various aldehydes were carried out using tungstophosphoric acid impregnated zirconium phosphate in solvent-free conditions to afford the corresponding 2-substituted arylbenzimidazole and arylbenzothiazole derivatives in good to excellent yields. This procedure constitutes a simple and practical green synthetic method for 2-arylbenzimidazoles and 2-arylbenzothiazoles and their structural analogs. Furthermore, the catalyst can be reused for several times but it will be less active. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:202,207, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20534 [source] Highly efficient and chemoselective acetalization of carbonyl compounds catalyzed by new and reusable zirconyl triflate, ZrO(OTf)2HETEROATOM CHEMISTRY, Issue 3 2009Majid Moghadam Various types of aromatic aldehydes were efficiently converted to their corresponding 1,3-dioxanes and 1,3-dioxolane with 1,3-propanediol and ethylene glycol, respectively, in the presence of catalytic amount of ZrO(OTf)2 in acetonitrile at room temperature. The catalyst can be reused several times without loss of its catalytic activity. Very short reaction times, selective acetalization of aromatic aldehydes in the presence of aliphatic aldehydes and ketones, very mild reaction conditions, reusability of the catalyst, and easy workup are noteworthy advantages of this method. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:131,135, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20523 [source] Highly Surface-roughened "Flower-like" Silver Nanoparticles for Extremely Sensitive Substrates of Surface-enhanced Raman ScatteringADVANCED MATERIALS, Issue 45 2009Hongyan Liang Abstract Surface-enhanced Raman scattering (SERS) is a new optical spectroscopic analysis technique with potential for highly sensitive detection of molecules. Recently, many efforts have been made to find SERS substrates with high sensitivity and reproducibility. In this Research News article, we provide a focused review on the synthesis of monodispersed silver particles with a novel, highly roughened, "flower-like" morphology by reducing silver nitrate with ascorbic acid in aqueous solutions. The nanometer-scale surface roughness of the particles can provide several hot spots on a single particle, which significantly increases SERS enhancement. The incident polarization-dependent SERS of individual particles is also studied. Although the different "hot spots" on a single particle can have a strong polarization dependency, the total Raman signals from an individual particle usually have no obvious polarization dependency. Moreover, these flower-like silver particles can be measured by SERS with high enhancement several times, which indicates the high stability of the hot spots. Hence, the flower-like silver particles here can serve as highly sensitive and reproducible SERS substrates. [source] Physiological costs of the hearing due to noise exposure, additional physical stress, and combined exposure to alcohol and cigarette smokeHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 3 2002H. Strasser In 2 studies, each with 5 test series, physiological costs of the hearing due to legally tolerable noise exposures of 94 dB (A) for 1 hr have been measured audiometrically. The temporary threshold shifts (TTS) and their restitution time, as well as cardiovascular responses in work-related heart rate increases, of 10 and 8 subjects (Ss), respectively, could be shown to be modulated by additional physical stress and combined exposure to alcohol (Study 1) and cigarette smoke (Study 2). Moderate dynamic muscle work (50 W) administered via a bicycle ergometer either immediately after noise, or simultaneous to the noise exposure, significantly reduced restitution time as well as the integrated restitution temporary threshold shift (IRTTS). A physical stress to 100 W,which exceeded the endurance level when demanded simultaneously to the noise exposure,did not show any favorable effects. However, if the same physical stress succeeded the noise exposure, and when it was interrupted several times for the audiometric measurements, it also brought about significant accelerations of the restitution processes. Some reductions in physiological costs of the hearing were found due to an intervening alcohol consumption (blood alcohol concentration , 0.08%) prior to the noise exposure and a simultaneous physical load of 50 W. Smoking 10 cigarettes instead of the consumption of alcohol was associated with a reduced TTS, but a prolonged restitution time. IRTTS as total physiological costs of the most unfavorable combination of noise, simultaneous high physical workload, and preceding smoke exposure was increased. The results of the test series with cigarette smoke,probably due to the small group of just 8 Ss and the counteracting effects of the agents carbon monoxide (CO) and nicotine,were not statistically significant, but these exposures were associated with a substantial activation of the cardiovascular system. Significant heart rate increases are evidence that CO and nicotine must not be neglected as influential factors in the context of physiological costs that the organism, and especially the hearing, has to pay for noise exposures. © 2002 Wiley Periodicals, Inc. [source] Evaluation of the cognitive, psychomotor and pharmacokinetic profiles of rupatadine, hydroxyzine and cetirizine, in combination with alcohol, in healthy volunteersHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 1 2006Manuel J. Barbanoj Abstract Introduction The Central Nervous System (CNS) impairment induced by moderate alcohol (ALC) ingestion may be enhanced if other drugs are taken simultaneously. Rupatadine (RUP) is a new H1 -antihistamine which also inhibits platelet activating factor (PAF) release in inflammatory reactions. Objective The main aim of the study was to assess the effects of ALC 0.8,g/Kg on RUP (10,mg and 20,mg) CNS effects. An evaluation of alcohol and RUP pharmacokinetics was also attained. Methods Eighteen healthy young volunteers of both sexes participated in a phase I, randomised, crossover, double-blind, placebo-controlled study. At 2-week intervals they received six treatments: (a) placebo (PLA), (b) ALC alone and ALC in combination with: (c) hydroxyzine 25,mg (HYD), (d) cetirizine 10,mg (CET), (e) RUP 10,mg or (f) RUP 20,mg. At baseline and several times thereafter, seven psychomotor performance tests (finger tapping, fine motoric skills, nystagmus, temporal estimation, critical-flicker-fusion frequency, ,d2' cancellation, simple reaction) and eleven subjective self-reports (drunkenness, sleepiness, alertness, clumsiness, anger, inattentiveness, efficiency, happiness, hostility, interest and extraversion) were carried out. Two-way (treatment, time) ANOVAs for repeated measures to each variable together with a multivariate non-parametric approach were applied. Plasma concentrations of alcohol, and of RUP and its metabolites, were quantified by validated immunofluorescence and LC/MS/MS methods, respectively. Plasma-time curves for all compounds were analysed by means of model-independent methods. Results The combination of alcohol with HYD, CET and RUP 20,mg produced more cognitive and psychomotor impairment as compared to alcohol alone, being the combination of alcohol and HYD the one which induced the greatest deterioration. The combination of alcohol and RUP 10,mg could not be differentiated from ALC alone. Subjective self-reports reflect effects on metacognition after the combination of alcohol with HYD and CET i.e. the increased objective impairment observed was not subjectively perceived by the subjects. No significant differences were obtained when comparing alcohol plasma concentrations assessed after the treatments evaluated. RUP showed a lineal kinetic relationship after 10 and 20,mg with a higher exposition to both metabolites assayed. Conclusions Present results showed that single oral doses of rupatadine 10,mg in combination with alcohol do not produce more cognitive and psychomotor impairment than alcohol alone. Higher doses of rupatadine, in combination with alcohol, may induce cognitive and psychomotor deterioration as hydroxyzine and cetirizine at therapeutic doses. Copyright © 2006 John Wiley & Sons, Ltd. [source] Operational performance of current synthetic aperture radar sensors in mapping soil surface characteristics in agricultural environments: application to hydrological and erosion modellingHYDROLOGICAL PROCESSES, Issue 1 2008Nicolas Baghdadi Abstract Synthetic aperture radar (SAR) sensors are often used to characterize the surface of bare soils in agricultural environments. They enable the soil moisture and roughness to be estimated with constraints linked to the configurations of the sensors (polarization, incidence angle and radar wavelength). These key soil characteristics are necessary for different applications, such as hydrology and risk prediction. This article reviews the potential of currently operational SAR sensors and those planned for the near future to characterize soil surface as a function of users' needs. It details what it is possible to achieve in terms of mapping soil moisture and roughness by specifying optimal radar configurations and the precision associated with the estimation of soil surface characteristics. The summary carried out for the present article shows that mapping soil moisture is optimal with SAR sensors at low incidence angles (<35 ). This configuration, which enables an estimated moisture accuracy greater than 6% is possible several times a month taking into account all the current and future sensors. Concerning soil roughness, it is best mapped using three classes (smooth, moderately rough, and rough). Such mapping requires high-incidence data, which is possible with certain current sensors (RADARSAT-1 and ASAR both in band C). When L-band sensors (ALOS) become available, this mapping accuracy should improve because the sensitivity of the radar signal to Soil Surface Characteristics (SSC) increases with wavelength. Finally, the polarimetric mode of certain imminent sensors (ALOS, RADARSAT-2, TerraSAR-X, etc.), and the possibility of acquiring data at very high spatial resolution (metre scale), offer great potential in terms of improving the quality of SSC mapping. Copyright © 2007 John Wiley & Sons, Ltd. [source] Resolution of persistent periapical infection by endodontic surgeryINTERNATIONAL ENDODONTIC JOURNAL, Issue 1 2004F. B. A. Ferreira Abstract Aim, To examine the surfaces of a root tip removed during surgical endodontic treatment for the presence of microorganisms. Summary, The present clinical case illustrates an endodontic retreatment of a maxillary premolar tooth with a fistula and periapical reaction. The case was under treatment for 1 year, during which an intracanal medicament was replaced several times. As the lesion did not decrease and exudate was persistent through the fistula and root canal, root end resection with root end filling was performed. Microbiological samples were collected from the fistula, where Propionibacterium acnes, a species associated with endodontic failures, was detected by appropriate anaerobic technique. The resected root apex was observed by scanning electron microscopy (SEM), which revealed cocci and fungal forms surrounding one of the foramina. After 12 months, the periapical lesion had reduced. Key learning points ,,Persistent extraradicular infections are not affected by the action of antimicrobial agents such as irrigants and medicaments used during root canal treatment. ,,Apical surgery is a suitable alternative for definitive removal of an established refractory infection, promoting repair of difficult cases. [source] Zinc Oxide Microstructures: Zinc Oxide Microtowers by Vapor Phase Homoepitaxial Regrowth (Adv. Mater.ADVANCED MATERIALS, Issue 8 20098/2009) Simultaneous axial and radial epitaxies can be achieved by growing ZnO microtowers by repeating a growth cycle several times, report Zhengwei Pan and co-workers on p. 890. The as-grown ZnO microtowers display a preferential growth habit of hexagonal prism,dihexagonal pyramid. Some rare or new growth habits such as dihexagonal prism,dihexagonal pyramid, hexagonal prism,trihexagonal pyramid and dihexagonal prism,trihexagonal pyramid (as shown on the cover) have also been identified. [source] Zinc Oxide Microtowers by Vapor Phase Homoepitaxial RegrowthADVANCED MATERIALS, Issue 8 2009Zhengwei Pan Simultaneous axial and radial epitaxies can be achieved on growing ZnO microtowers through a regrowth technique of repeating the same growth circle for several times. The as-grown ZnO microtowers display a preferential growth habit of hexagonal prism,dihexagonal pyramid. The apexes of the pyramidal towers are very sharp, with a radius of curvature as small as 2 to 50 nm. [source] Consumers' awareness and information need about food hygiene in Korea: focused on pesticide residues and food borne illnessINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2003Meera Kim This study investigated consumers' awareness and information need about food hygiene especially focused on pesticide residues and food borne illness in Korea. The data were collected from 350 adults living in Daegu and Busan, Korea by a self-administered questionnaire. Frequency and chi-square tests were conducted by SPSS. The results of the survey were as follows: Firstly the consumers' concerns about food hygiene were high. About three-fourths of the respondents answered that they were ,somewhat' or ,highly' concerned about pesticide residues and food borne illness. Especially women and the older showed more concerns than men and the younger. Secondly, the respondents worried about eating vegetables, fruits and grains in turn because of pesticide residues, and did not trust the results from food hygiene tests by the Government. Thirdly, three-fourths of the respondents used the way to wash food stuffs with water several times to clean pesticide residues. Fourth, about four-fifths of the subjects worried about food borne illness caused by fish to the extreme and about two-thirds answered that un-fresh or contaminated food stuffs were the major factor of food borne illness in cooking. Finally, the respondents primarily wanted to get the information about harmfulness of pesticide residues in foods, and methods to choose fresh food regarding food borne illness. Under the situation of the lack of educational programs for food hygiene in Korea, the educational contents for food hygiene to improve public health can be developed on the basis of this study. [source] | ||||||||||||||||||||||||||||||||||||||||||||||