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Cleaners
Selected AbstractsEctoparasites: are they the proximate cause of cleaning interactions?JOURNAL OF FISH BIOLOGY, Issue 2003I. M. Côté We tested the importance of ectoparasites in cleaning symbioses by comparing the activity of Caribbean cleaning gobies (Elacatinus evelynae) and of their clients during three daily periods (early morning, midday and late afternoon) in which ectoparasite availability varied naturally. Emergence from the benthos of gnathiid isopod larvae, the main target of cleaning goby predation, was higher at night, when cleaners are inactive, than during the day. Overall ectoparasite loads also tended to be higher on clients in the morning. This coincided with higher rates of visits to cleaning stations by client fish in the morning than at midday, but high rates of client visits were also recorded in the late afternoon. Clients were more likely to adopt stereotypical incitation poses, which increase the likelihood of being cleaned, in the morning than later in the day. Inspection bouts by cleaning gobies were longest in the morning. Cleaner and client behaviours therefore change predictably in response to natural diurnal variation in ectoparasite availability. These results add to a growing number of studies supporting the idea that cleaning symbioses are mutualisms dependent on ectoparasite removal. [source] The Air is Always Cleaner on the Other Side: Race, Space, and Ambient Air Toxics Exposures in CaliforniaJOURNAL OF URBAN AFFAIRS, Issue 2 2005Manuel Pastor Jr. This article uses U.S. EPA's National Air Toxics Assessment (NATA) for 1996 to examine environmental inequality in California, a state that has been a recent innovator in environmental justice policy. We first estimate potential lifetime cancer risks from mobile and stationary sources. We then consider the distribution of these risks using both simple comparisons and a multivariate model in which we control for income, land use, and other explanatory factors, as well as spatial correlation. We find large racial disparities in California's "riskscape" as well as inequalities by other factors and suggest several implications for environmental and land use policy. [source] Biotech news and viewsBIOTECHNOLOGY JOURNAL, Issue 5 2009Article first published online: 18 MAY 200 Therapeutic tobacco Cleaner, more efficient cancer drug production The light at the end of the tunnel [source] Automated egg-collecting and pupa-separator system for medfly mass-rearing facilitiesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2008Ivan Morávek Abstract The new automated egg-collecting system and pupa-separator device described here substantially reduces labour during medfly [Ceratitis capitata (Wiedemann) (Diptera: Tephritidae)] mass production. The egg-collecting system gathers eggs dropping from the cage's oviposition net into a continuous stream of water, after which they accumulate in an egg-collecting sieve. The system provides an optimal environment for eggs, keeping them in a slow stream of well-oxygenated water. A pupa separator was designed to enable the separation of pupae from the pupation medium by sucking off the medium through a slowly moving sieving belt. The smaller particles of pupation medium are removed by a vacuum cleaner located under the circular sieving belt, and the pupae are collected in a collecting box. Quality control tests of the eggs collected and pupae separated have shown that neither system has a negative effect on the quality of the eggs or the pupae. [source] Temporal Variation in Cleanerfish and Client Behaviour: Does It Reflect Ectoparasite Availability?ETHOLOGY, Issue 6 2003Isabelle M. Côté We tested the importance of ectoparasites as the proximate cause of cleaning interactions by comparing the activity of Caribbean cleaning gobies (Elacatinus evelynae) and of their clients during three daily periods (early morning, midday, and late afternoon) in which ectoparasite availability varied naturally. Emergence from the benthos of gnathiid isopod larvae, the main target of cleaning goby predation, was higher at night, when cleaners were inactive, than during the day. As a result, overall ectoparasite loads on client fish tended to be higher in the morning. Inspection bouts by cleaning gobies were longest in the morning, but also at midday when ectoparasite availability on clients was lower. Client fish were observed at cleaning stations most often in the afternoon, when they harboured few ectoparasites, but they were more likely to adopt incitation poses, which increase the likelihood of being cleaned, in the morning than later in the day. Most cleaner and client behaviours therefore did not change predictably in response to natural diurnal variation in ectoparasite availability. Our study suggests that the ultimate and proximate causes of cleaning behaviour need not necessarily coincide. [source] Structure of a human telomeric DNA sequence stabilized by 8-bromoguanosine substitutions, as determined by NMR in a K+ solutionFEBS JOURNAL, Issue 14 2007Akimasa Matsugami The structure of human telomeric DNA is controversial; it depends upon the sequence contexts and the methodologies used to determine it. The solution structure in the presence of K+ is particularly interesting, but the structure is yet to be elucidated, due to possible conformational heterogeneity. Here, a unique strategy is applied to stabilize one such structure in a K+ solution by substituting guanosines with 8-bromoguanosines at proper positions. The resulting spectra are cleaner and led to determination of the structure at a high atomic resolution. This demonstrates that the application of 8-bromoguanosine is a powerful tool to overcome the difficulty of nucleic acid structure determination arising from conformational heterogeneity. The obtained structure is a mixed-parallel/antiparallel quadruplex. The structure of telomeric DNA was recently reported in another study, in which stabilization was brought about by mutation and resultant additional interactions [Luu KN, Phan AT, Kuryavyi V, Lacroix L & Patel DJ (2006) Structure of the human telomere in K+ solution: an intramolecular (3+1) G-quadruplex scaffold. J Am Chem Soc 128, 9963,9970]. The structure of the guanine tracts was similar between the two. However, a difference was seen for loops connecting guanine tracts, which may play a role in the higher order arrangement of telomeres. Our structure can be utilized to design a small molecule which stabilizes the quadruplex. This type of molecule is supposed to inhibit a telomerase and thus is expected to be a candidate anticancer drug. [source] Aliovalent Substitutions in Olivine Lithium Iron Phosphate and Impact on Structure and PropertiesADVANCED FUNCTIONAL MATERIALS, Issue 7 2009Nonglak Meethong Abstract Lithium transition metal phosphate olivines are enabling a new generation of high power, thermally stable, long-life rechargeable lithium batteries that may prove instrumental in the worldwide effort to develop cleaner and more sustainable energy. Nanoscale (<100,nm) derivatives of the olivine family LiMPO4 (M,=,Fe, Mn, Co, Ni) are being adopted in applications ranging in size scale from hybrid and plug-in hybrid electric vehicles to utilities-scale power regulation. Following the previous paradigm set with intercalation oxides, most studies have focused on the pure ordered compounds and isovalent substitutions. In contrast, even the possibility for, and role of, aliovalent doping has been widely debated. Here, critical tests of plausible defect compensation mechanisms using compositions designed to accommodate Mg2+, Al3+, Zr4+, Nb5+ ions on the M1,and/or M2 sites of LiFePO4 with appropriate charge-compensating defects are carried out, and conclusive crystallographic evidence for lattice doping, e.g., up to at least 12 atomic percent added Zr, is obtained. Structural and electrochemical analyses show that doping can reduce the lithium miscibility gap, increase phase transformation kinetics during cycling, and expand Li diffusion channels in the structure. Aliovalent modifications may be effective for introducing controlled atomic disorder into the ordered olivine structure to improve battery performance. [source] Influence of the pulpal components on human dentine permeability in vitroINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2005P. Puapichartdumrong Abstract Aim, To examine the influence of the retained pulpal components on permeability of human dentine by monitoring drug diffusion. Methodology, Twelve intact dentine discs were prepared from freshly extracted human third molars. The dentine surface on the enamel side was etched with 10% polyacrylic acid for 30 s. The drug diffusion test was carried out before and after removal of the retained pulpal components. Each dentine disc was inserted between two plastic chambers; enamel- and pulpal-side chambers, which were filled with 0.05 mol L,1 naproxen sodium (NA) and phosphate-buffered saline (PBS), respectively. After 10 min, the solution on the pulpal-side chamber was collected to determine the concentration of NA using a spectrophotometer. To remove the retained pulpal components and residual NA, the pulp chamber of each disc was washed out with PBS and placed in an ultrasonic cleaner. After removal of these components and the residual NA, the drug diffusion test was repeated. The inner surface of the pulp chamber was observed using scanning electron microscopy (SEM) before and after the removal of the retained pulpal components. Results, The amount of NA that diffused through dentine into the pulp was significantly higher after the pulp chamber was washed out with PBS (paired t -test, P < 0.05). SEM observation demonstrated the presence of the retained pulpal components, odontoblastic layer and some parts of subodontoblastic zone, covering the surface of predentine. These components were removed after the pulp chamber was washed out with PBS followed by cleaning in an ultrasonic cleaner. Conclusions, The presence of retained pulpal components had a significant influence on drug diffusion through dentine discs. [source] Effectiveness of different techniques for removing gutta-percha during retreatmentINTERNATIONAL ENDODONTIC JOURNAL, Issue 1 2005A. V. Masiero Abstract Aim, To evaluate the effectiveness of various techniques for removing filling material from root canals in vitro. Methodology, Eighty extracted mandibular premolar teeth were selected for the study. The teeth were root filled using thermomechanical compaction of gutta-percha. After 8 months, the filling material was removed and canals were reinstrumented using the following techniques: group I , hand instrumentation with K-type files (SybronEndo, Orange, CA, USA); group II , K3 Endo System (SybronEndo); group III , M4 system (SybronEndo) with K-type files (SybronEndo); and group IV , Endo-gripper system (Moyco Union Broach, York, PA, USA) with K-type files (SybronEndo). The amount of filling debris remaining on root canal walls was assessed radiographically; the images were digitized and analysed using AutoCAD 2000 software. Total canal area, area of the cervical, middle and apical thirds, and area of remaining filling material were outlined by one operator. The ratios between these areas were calculated as percentages of remaining debris. Thereafter, data were analysed by means of one-way anova and the post-hoc Duncan test to identify differences between the four techniques. Results, Multiple comparisons of the percentages of remaining filling material in the entire canal did not reveal any significant differences between the methods of removal. However, when each third was analysed separately, significant differences for remaining debris were present between groups. The apical third had the most remaining material, whilst the cervical and middle thirds were significantly cleaner (P = 0.002). Comparison of the techniques revealed that teeth instrumented with K3 rotary instruments had a lower ratio of remaining filling material in the apical third (P = 0.012). Conclusion, In the apical third, K3 rotary instruments were more efficient in removing gutta-percha filling material than the other techniques, which were equally effective for the other thirds. [source] Light and scanning electron microscopic evaluation of GlydeÔ File Prep in smear layer removalINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2003T. S. Lim Abstract Aim, To evaluate the effectiveness of GlydeÔ File Prep used in conjunction with sodium hypochlorite irrigation in the removal of smear layer produced during root canal instrumentation. Methodology, Thirty-nine extracted human teeth with single root canals were used. Access cavities were prepared and the teeth divided into three groups of 13 teeth each. Each group was treated by one of the three different regimes of irrigation and conditioning during root canal instrumentation. Group A: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 1% NaOCl; group B: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 17% EDTA; group C: GlydeÔ File Prep coated on each instrumentation file used in conjunction with 0.5 mL 1% NaOCl irrigation after each file size and an additional final irrigation of 10 mL 1% NaOCl. The teeth were then longitudinally grooved and sectioned. Root canal cleanliness was evaluated with the aid of a Nikon light microscope (×40 and ×100) and scanning electron microscope (×1000 and ×3000). The debris scores obtained at three canal regions were compared statistically within the same group and among different groups using repeated measurements of analysis of variance (anova) with Bonferroni adjustments and anova with posthoc Tukey HSD, respectively. Results, The canals treated with EDTA and GlydeÔ File Prep were significantly cleaner than those treated with NaOCl alone. The apical region of the root canals generally displayed more residual smear layer, but the difference was not significant. Conclusions, Used in conjunction with NaOCl irrigation, GlydeÔ File Prep was effective in removing smear layer produced during root canal instrumentation. [source] A scanning electron microscopic study of debris and smear layer remaining following use of GT rotary instrumentsINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2002G. Gambarini Abstract Aim The aim of the present study was to assess debris and smear layer remaining following canal preparation with GT rotary instruments. Methodology Sixteen freshly extracted single-rooted premolar teeth were instrumented with GTÔ rotary instruments using a crown-down preparation technique. All specimens were flushed with 2 mL of 5% NaOCl between each rotary instrument. At the end of instrumentation the following final irrigation sequence was repeated two times: 2 mL of EDTA + Cetrimide for 1 min (Largal Ultra, Septodont, France) and 2 mL of 5% NaOCl for 5 min. A final flush with saline solution was made to halt any chemical activity. Two other uninstrumented teeth that were not irrigated served as controls. All teeth were split longitudinally and prepared for SEM evaluation. The presence of debris and smear layer was evaluated from photomicrographs at ×200 and ×1000 magnification taken in the apical, middle and coronal thirds of the canals. Blind evaluation was performed by two trained observers and scores were compiled separately. A five category scoring system for debris and smear layer was used. Values obtained were tabulated and statistical analysis was carried out using a parametric chi-squared test. Results Statistical analysis showed that there was no significant difference between the three regions of the root canals (P > 0.05) for debris. Comparison of the removal of the smear layer between the three regions showed that there was a statistically significant difference between all parts, especially between the coronal and apical thirds (P < 0.001). Overall, the coronal sections were cleaner than the middle and apical sections. The uninstrumented canals showed walls completely covered with tissue, confirming that specimen preparation alone did not remove tissue. Conclusions Under the conditions of the present study GTÔ rotary instruments removed debris effectively, but left root canal walls covered with smear layer, particularly in the apical third. [source] The efficacy of gutta-percha removal using ProFilesINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2001J. J. Ferreira Abstract Aim The purpose of this study was to compare the efficacy in vitro of gutta-percha removal from obturated root canals using ProFiles. Methodology Forty-eight human root canals with curvatures ranging between 25 and 45° were instrumented by a standardized method to an apical ISO size 30 and 0.04 taper. They were obturated with vertically condensed gutta-percha. Retreatment was performed with the following techniques: K-Flexofiles with chloroform; Hedstrom files with chloroform; ProFiles 0.04 taper with chloroform; ProFiles 0.04 taper alone. The time for each method was measured. A microfocal macroradiographic technique was used to evaluate the amount of debris remaining within the root canals after the retreatment procedure. Roots were divided into apical, middle and coronal parts and scored on a scale of 0 (no debris) to 3 (>50% of walls covered with debris) by trained observers on two separate occasions. Results The scores for debris remaining within root canals for K-Flexofiles with chloroform and ProFiles with chloroform were the lowest and not significantly different at all three levels of the roots examined (P > 0.05), and Hedstrom files with chloroform and ProFiles with chloroform were not significantly different in the apical part. In general, coronal parts were cleaner than apical parts. The difference in scores at the three levels between ProFiles with chloroform and ProFiles alone were each significant (P < 0.01). Instrumentation using ProFiles with chloroform (mean 6.42 min) was significantly faster than using hand files (mean 11.67 min) (P < 0.01). Conclusion The results indicated that ProFiles or hand files with chloroform produced similarly clean canals, but that ProFiles were faster. [source] Cleaning efficacy of two apical preparation regimens following shaping with hand files of greater taperINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2000P. J. Lumley Abstract Aim The aim of this investigation was to assess canal cleaning following shaping with hand files of greater taper. Methodology Thirty mesial canals and 30 distal canals in mandibular molars were prepared with .08 and .10 hand files of greater taper, respectively. Following initial preparation, 0.02 instruments were used incrementally shorter in a stepback manner. In half the canals instrumentation was performed to size 35 1 mm short of the canal terminus. In the other half the series was continued through to size 60 using stepback increments of half to one millimetre as appropriate (foramen size was maintained at size 20 in all groups). Sodium hypochlorite (4.5%) and REDTA (17%) were used as irrigants for all groups. Cleaning efficacy was evaluated by scoring the amount of remaining debris using a light microscope (×50) and calibrated eyepiece micrometer (range 0,3). Results Canals stepped back through to a size 60 were significantly cleaner than those instrumented to a size 35 only (Mann,Whitney P < 0.05). Conclusion Refining the apical region of canal preparation by stepping back through to a size 60 reduced remaining debris following shaping with files of greater taper. [source] Pyoderma gangrenosum of the scalp treated with cyclosporine AINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2002Pasquale Patrone MD A 56-year-old woman presented with an ulcer, with a depth of 9 mm, on the vertex and frontal parietal regions of the scalp. The lesion had a round shape (diameter, 7 cm), with clear-cut margins and vertical borders sinking vertically to a bottom that was entirely covered with purulent fibrinous yellowish matter and greenish colored necrotic tissue. Other numerous small roundish ulcers were present next to the large ulcer. These had irregular margins with a yellowish fibrinous bottom (Fig. 1). The patient reported the appearance of two small ulcers on the left and on the right frontal parietal regions about 1 year earlier. These had been treated locally with antimicrobials and antiseptics with no result. During the 2 months prior to our evaluation, a few small round-shaped ulcers had appeared on the scalp. These had progressively increased in size and number. Figure Figure 1 . Large ulcer with clear-cut margins, covered by purulent fibrinous matter, and other small roundish ulcers The patient had been an insulin-dependent diabetic for 23 years. Hematochemical examinations showed no significant alterations, except for a rise in glycemia. Urine examination gave normal results. Carcinoembryonic antigen and lymphocytic phenotyping indices were normal. Echographic, endoscopic, and radiocontrast studies of the abdomen did not reveal the presence of lesions either in the gastrointestinal tract or in other organs. Samples of ulcerous tissue were collected from the scalp to perform histologic and microbiologic analysis in search of fungi and bacteria. This last examination revealed the presence of Staphylococcus aureus and Candida parapsylosis. Direct search for mycobacteria was negative. Histology indicated the presence of dermal granulomatous inflammation with giant multinucleate cells, associated with large zones of suppuration and colliquative necrosis. While waiting to complete the diagnostic course, topical antiseptic, antimicrobial, and fibrinolytic therapy was administered; subsequently, as this did not lead to any improvement, systemic treatment with cyclosporine A (5 mg/kg/day) was started. Rapid improvement of the clinical picture occurred. The ulcers appeared cleaner from the first 2 weeks of treatment, radial growth stopped, and the margins were slightly more superficial. The patient continued with immunomodulating therapy at home over a period of 7 months. The dose was progressively reduced until, over a period of about 3 months, complete re-epithelialization of the lesion, with subsequent partial regrowth of the hair, was obtained (Figs 2 and 3). No relapses were observed 1 year after treatment was suspended. Figure 2. Partial re-epithelialization of the lesion with partial regrowth of the hair Figure 3. Scar and hair regrowth [source] The perspectives of energy production from coal-fired power plants in an enlarged EUINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 9 2004P. Grammelis Abstract The aim of this paper is to present the current status of the coal-fired power sector in an enlarged EU (EU-15 plus EU member candidate states) in relation with the main topics of the European Strategy for the energy production and supply. It is estimated that 731 thermoelectric units, larger than 100 MWe, are operating nowadays, and their total installed capacity equals to 200.7 GWe. Coal contribution to the total electricity generation with reference to other fuel sources, is by far more intensive in the non-EU part (EU member candidate states), compared to the EU member states. It is expected that even after the enlargement, the European Union will strongly being related to coal. Enlargement will bring additional factors into play in order to meet the requirements of rising consumption, growing demand for conventional fuels and increasing dependence on imports. Besides the technology, boiler size, efficiency, age and environmental performance will determine the necessities of the coal-fired power sector in each country. Depending on the case, lifetime extension measures in operating coal-fired power plants or clean coal technologies can play an important role towards the energy sector restructuring. Low efficiency values in the non-EU coal-fired units and heavily aged power plants in EU countries will certainly affect decisions in favour of upgrading or reconstruction. The overall increase of efficiency, the reduction of harmful emissions from generating processes and the co-combustion of coal with biomass and wastes for generating purposes indicate that coal can be cleaner and more efficient. Additionally, plenty of rehabilitation projects based on CCT applications, have already been carried out or are under progress in the EU energy sector. The proclamations of the countries' energy policies in the coming decades, includes integrated renovation concepts of the coal-fired power sector. Further to the natural gas penetration in the electricity generation and CO2 sequestration and underground storage, the implementation of CCT projects will strongly contribute to the reduction of CO2 emissions in the European Union, according to the targets set in the Kyoto protocol. In consequence, clean coal technologies can open up new markets not only in the EU member candidate states, but also in other parts of the world. Copyright © 2004 John Wiley & Sons, Ltd. [source] Synthesis of carvacrol by Friedel,Crafts alkylation of o -cresol with isopropanol using superacidic catalyst UDCaT-5JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 10 2009Ganapati D. Yadav Abstract BACKGROUND: Alkylation of o -cresol with propylene or isopropyl alcohol (IPA) over solid acid catalysts results in the formation of carvacrol, which finds potential applications in the synthesis of fine chemicals, intermediates, specialty chemicals, flavours and fragrances. RESULTS: The present work covers evaluation of novel mesoporous superacidic catalysts namely UDCaT-4, UDCaT-5 and UDCaT-6 in the greener synthesis of carvacrol. The catalysts are modified versions of zirconia showing high catalytic activity, stability and reusability. The catalytic activity increases in the following order: UDCaT-5 > UDCaT-4 > UDCaT-6 > sulfated zirconia. The process was optimized and a mathematical model developed to describe the reaction pathway in liquid phase. Carvacrol could be efficiently obtained with a selectivity up to 82% at an isopropanol conversion of 98% after 2 h over UDCaT-5 at 180 °C. CONCLUSION: The reaction is free from any external mass transfer as well as intraparticle diffusion limitations and is intrinsically kinetically controlled. An overall second-order kinetic equation was used to fit the experimental data. The activation energy was found to be 19.2 kcal/mol. The reaction was carried out without any solvent in order to make the process cleaner and greener. Copyright © 2009 Society of Chemical Industry [source] Time of flight versus ion trap MS coupled to CE to analyse intact proteinsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 10 2008Guillaume L. Erny Abstract In this work, two different CE-MS instruments, namely, CE-ESI-IT-MS and CE-ESI-TOF-MS, applied to analyse intact proteins from complex samples are investigated. The aim of this work was to compare both instruments in terms of LOD, number of proteins detected, and precision and repeatability in the determination of the protein relative molecular mass. Results show that although CE-ESI-IT-MS provides cleaner MS spectra of intact proteins, CE-ESI-TOF-MS allows the identification of a higher number of proteins from complex matrices in an easier way. Performance in terms of peak area reproducibility, LOD and precision in the determination of the molecular mass were similar for both instruments. The usefulness of the optimised CE-ESI-IT-MS and CE-ESI-TOF-MS conditions was demonstrated by studying the zein-proteins composition of three natural maize lines and their corresponding transgenic lines, showing no significant differences. [source] Improved tomographic reconstructions using adaptive time-dependent intensity normalizationJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2010Valeriy Titarenko The first processing step in synchrotron-based micro-tomography is the normalization of the projection images against the background, also referred to as a white field. Owing to time-dependent variations in illumination and defects in detection sensitivity, the white field is different from the projection background. In this case standard normalization methods introduce ring and wave artefacts into the resulting three-dimensional reconstruction. In this paper the authors propose a new adaptive technique accounting for these variations and allowing one to obtain cleaner normalized data and to suppress ring and wave artefacts. The background is modelled by the product of two time-dependent terms representing the illumination and detection stages. These terms are written as unknown functions, one scaled and shifted along a fixed direction (describing the illumination term) and one translated by an unknown two-dimensional vector (describing the detection term). The proposed method is applied to two sets (a stem Salix variegata and a zebrafish Danio rerio) acquired at the parallel beam of the micro-tomography station 2-BM at the Advanced Photon Source showing significant reductions in both ring and wave artefacts. In principle the method could be used to correct for time-dependent phenomena that affect other tomographic imaging geometries such as cone beam laboratory X-ray computed tomography. [source] What makes a species central in a cleaning mutualism network?OIKOS, Issue 8 2010Cristina Sazima Mutualisms often form networks of interacting species, characterized by the existence of a central core of species that potentially drive the ecology and the evolution of the whole community. Centrality measures allow quantification of how central or peripheral a species is within a network, thus informing about the role of each species in network organization, dynamics, and stability. In the present study we addressed the question whether the structural position of species in the network (i.e. their topological importance) relates to their ecological traits. We studied interactions between cleaner and client reef fishes to identify central and peripheral species within a mutualistic network, and investigated five ecological correlates. We used three measures to estimate the level of centrality of a species for distinct structural patterns, such as the number of interactions and the structural proximity to other species. Through the use of a principal component analysis (PCA) we observed that the centrality measures were highly correlated (92.5%) in the studied network, which indicates that the same species plays a similar role for the different structural patterns. Three cleaner and ten client species had positive values of centrality, which suggests that these species are modulating ecological and evolutionary dynamics within the network. Higher centralities were related to higher abundances and feeding habits for client fishes, but not for cleaners. The high correlation between centrality measures in the present study is likely related to the nested structure of the cleaning network. The cleaner species' set, by having central species that are not necessarily the most abundant ones, bears potentially more vulnerable points for network cohesiveness. Additionally, the present study generalizes previous findings for plant,animal mutualisms, as it shows that the structure of marine mutualisms is also related to a complex interplay between abundance and niche-related features. [source] Randomised controlled trial of the effects of two rigid gas permeable (RGP) contact lens materials and two surface cleaners on straylight valuesOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 5 2009Marten F. Fortuin Abstract Purpose:, In a double-masked randomized controlled crossover study we investigated both the retinal responses to straylight, and the effects of lens cleaners on straylight values, in two different RGP contact lens materials. Methods:, Thirty patients (20,59 years) wearing RGP lenses were refitted with new lenses made of Boston XO material in one eye and made of Comfort O2 (ONSI-56) material in the other eye. Reported wetting angles for the Boston XO material (103°) and for the ONSI-56 material (7.2°) were obtained by sessile drop measurements. After refitting, the study comprised three 5-week trial periods. In Period 1 half of the participants (Group A) wore Boston XO lenses in their right eye and Comfort O2 (ONSI-56) lenses in their left eye, and the other half (Group B) vice versa. In Period 2 Group A wore Comfort O2 (ONSI-56) lenses in their right eye and Boston XO lenses in their left, and Group B vice versa. All participants used Miraflow cleaner during periods 1 and 2. In Period 3, during which all participants used Boston cleaner, Group A wore Boston XO lenses in their right eye and Comfort O2 (ONSI-56) lenses in their left eye and Group B vice versa. Straylight data (log S) were obtained with and without contact lenses using the Oculus C-Quant straylight meter in all three periods. Central corneal thickness (CCT) was measured in the second and third periods. Results:, When not wearing lenses (n = 60 eyes) at the end of the second 5 week trial period straylight was measured twice with averages of 1.07 log S, and the corrected CCT measurements averaged 546 ,m. Straylight values with Comfort O2 (ONSI-56) reached 1.15 log S at the end of both the second (n = 25 eyes) and third periods (n = 23 eyes). Straylight values with Boston XO were 1.17 log S (n = 26 eyes) at the end of the second period, and 1.16 log S (n = 25 eyes) at the end of the third period. Conclusions:, Existing RGP lens wearers refitted with new lenses with different contact angles, made of Boston XO and Comfort O2 (ONSI-56) showed, over three 5 week periods, relatively small increases in straylight, which were functionally comparable, irrespective of the type of lens material or lens cleaner used. At every visit, straylight values and CCTs returned to baseline levels after RGP lens removal, confirming that the straylight fluctuations were mainly due to scattering from the RGP lenses; or tear film interaction; or a combination of both. [source] Airways inflammation after exposure in a swine confinement building during cleaning procedureAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2002Britt-Marie Larsson PhD Abstract Background Healthy volunteers exposed for 3 hr during weighing of pigs develop an airway inflammation characterized by a massive influx of neutrophilic granulocytes in the upper and lower airways and increased bronchial responsiveness to methacholine. The purpose of the present study was to investigate health effects from exposure during cleaning of the swine confinement building and to evaluate the effect of a respiratory protection device. Methods Sixteen subjects were exposed for 3 hr during cleaning of a swine confinement room with a high-pressure cleaner. Seven out of sixteen subjects were equipped with a mask during exposure. Results The bronchial responsiveness increased in all subjects following exposure, significantly more in the group exposed without a mask (P,<,0.05). The cell concentration (mainly neutrophilic granulocytes) in nasal lavage fluid as well as the concentration of interleukin-8, increased significantly only in those subjects exposed without a respiratory protection device. In peripheral blood, an increase of neutrophilic granulocytes was observed in both groups, although it was significantly higher in the group without mask (P,<,0.05). The inhalable dust level was 0.94 (0.74 , 1.55) mg/m3 and respirable dust 0.56 (0.51,0.63) mg/m3. Conclusion Exposure to dust aerosols during the cleaning of the interior of a swine confinement building induces increased bronchial responsiveness and an acute inflammatory reaction in the upper airways. The use of a mask attenuated but did not abolish the inflammatory response. This suggests that gases and/or ultrafine particles in this environment could be important factors in the development of increased bronchial responsiveness. Am. J. Ind. Med. 41:250,258, 2002. © 2002 Wiley-Liss, Inc. [source] On the application of an experimental multipolar pseudo-atom library for accurate refinement of small-molecule and protein crystal structuresACTA CRYSTALLOGRAPHICA SECTION A, Issue 2 2007Bartosz Zarychta With an increasing number of biomacromolecular crystal structures being measured to ultra-high resolution, it has become possible to extend to large systems experimental charge-density methods that are usually applied to small molecules. A library has been built of average multipole populations describing the electron density of chemical groups in all 20 amino acids found in proteins. The library uses the Hansen & Coppens multipolar pseudo-atom model to derive molecular electron density and electrostatic potential distributions. The library values are obtained from several small peptide or amino acid crystal structures refined against ultra-high-resolution X-ray diffraction data. The library transfer is applied automatically in the MoPro software suite to peptide and protein structures measured at atomic resolution. The transferred multipolar parameters are kept fixed while the positional and thermal parameters are refined. This enables a proper deconvolution of thermal motion and valence-electron-density redistributions, even when the diffraction data do not extend to subatomic resolution. The use of the experimental library multipolar atom model (ELMAM) also has a major impact on crystallographic structure modelling in the case of small-molecule crystals at atomic resolution. Compared to a spherical-atom model, the library transfer results in a more accurate crystal structure, notably in terms of thermal displacement parameters and bond distances involving H atoms. Upon transfer, crystallographic statistics of fit are improved, particularly free R factors, and residual electron-density maps are cleaner. [source] Successful unsaturated zone treatment of PCE with sodium permanganateREMEDIATION, Issue 2 2009John R. Hesemann In situ chemical oxidation (ISCO) with permanganate has been widely used for soil and groundwater treatment in the saturated zone. Due to the challenges associated with achieving effective distribution and retention in the unsaturated zone, there is a great interest in developing alternative injection technologies that increase the success of vadose-zone treatment. The subject site is an active dry cleaner located in Topeka, Kansas. A relatively small area of residual contamination adjacent to the active facility building has been identified as the source of a large sitewide groundwater contamination plume with off-site receptors. The Kansas Department of Health and Environment (KDHE) currently manages site remedial efforts and chose to pilot-test ISCO with permanganate for the reduction of perchloroethene (PCE) soil concentrations within the source area. KDHE subsequently contracted Burns & McDonnell to design and implement an ISCO pilot test. A treatability study was performed by Carus Corporation to determine permanganate-soil-oxidant-demand (PSOD) and the required oxidant dosing for the site. The pilot-test design included an ISCO injection approach that consisted of injecting aqueous sodium permanganate using direct-push technology with a sealed borehole. During the pilot test, approximately 12,500 pounds of sodium permanganate were injected at a concentration of approximately 3 percent (by weight) using the methods described above. Confirmation soil sampling conducted after the injection event indicated PCE reductions ranging from approximately 79 to more than 99 percent. A follow-up treatment, consisting of the injection of an additional 6,200 pounds of sodium permanganate, was implemented to address residual soil impacts remaining in the soil source zone. Confirmation soil sampling conducted after the treatment indicated a PCE reduction of greater than 90 percent at the most heavily impacted sample location and additional reductions in four of the six samples collected. © 2009 Wiley Periodicals, Inc. [source] "Honey, Have You Seen Our Hamster?"THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 3 2003Consumer Evaluations of Autonomous Domestic Products Several autonomous products have been launched in the marketplace in the past few years. These autonomous products do not need any human intervention but operate on their own. An example of such an autonomous product is the self-initiating, independent vacuum cleaner that determines when a floor or room needs to be vacuumed, and does the job by itself, returning to the charging station when it needs to recharge its battery. It is unclear, however, to what extent consumers appreciate this autonomy. Autonomous products take over tasks from the user, which leaves the user the opportunity to take part in other activities. However, consumers may also consider these products complex and the use and purchase of such products risky. In addition, people often show a desire for control and may be reluctant to hand over some control to autonomous products. The advantages of autonomous products may thus be partly compensated by several disadvantages. The present study aims to explain overall consumer appreciation for autonomous products by integrating the above-mentioned factors in a conceptual model. This conceptual framework was tested in an experiment (N=77). The results reveal that consumers perceive highly autonomous products as more risky and complex than less autonomous products. Perceived risk negatively influenced overall consumer appreciation whereas complexity did not affect consumers' appreciation. Relative advantage, however, compensates the negative effect of perceived risk on overall consumer appreciation. Also, contrary to our expectations, we found that people with a high desire for control perceive less risk. We conclude with managerial implications for developers and marketers of autonomous domestic products. [source] Transgenic wheat: where do we stand after the first 12 years?ANNALS OF APPLIED BIOLOGY, Issue 1 2005H.D. Shewry Jones Abstract Wheat was among the last of the major crops to be transformed (in 1992), and transformation is still difficult, with a lower efficiency than that for maize and rice. However, the recent development of Agrobacterium -based systems is set to improve the precision of the process, while new methods of selection, removal of unnecessary DNA sequences, gene targeting and in vivo mutagenesis will make the process cleaner and more acceptable to regulatory authorities and consumers. Our current work is focussed on using transformation to understand and manipulate aspects of grain processing quality, notably dough strength and texture for milling. However, it is clear that a major priority for future work will be to improve nutritional quality, including vitamin and mineral contents for the developing world and starch digestibility and dietary fibre content and composition for developed countries. [source] Preparation of N -alkylpyridinium aryl ketone derivatives via the surfactant promoted cross-coupling reaction of N -alkylpyridiniumboronic acids with carboxylic anhydride in water at room temperatureAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2009H. Matondo Abstract The palladium (II) chloride catalyzed coupling reaction of N -alkylpyridiniumboronic acids with benzoic anhydride was carried out smoothly in water to give high yields of ketones without the use of a phosphine ligand. The reaction was conducted under mild conditions at room temperature. In this article, by focusing on the Suzuki reaction, it is shown how this method can impact modern synthetic chemistry, making reactions faster, easier and cleaner. Copyright © 2009 John Wiley & Sons, Ltd. [source] MORNING CLEANING: JEFF WALL AND THE LARGE GLASSART HISTORY, Issue 5 2009CHRISTINE CONLEY Jeff Wall's Morning Cleaning, Mies van der Rohe Foundation, Barcelona, 1999, is a cinematographic digital transparency picturing the German Pavilion designed by Mies for the 1929 International Exposition in Barcelona and reconstructed in the 1980s. The tableau involves the arrested action of a male cleaner, oblivious to the gaze of the spectator, as he washes the windows separating the interior from an outdoor pool, where the morning sun illuminates Georg Kolbe's sculpture Dawn. Contrary to Michael Fried's reading of Morning Cleaning as a renewal of the antitheatrical aims of High Modernist painting, this essay looks to Duchamp's Large Glass as the model for its structuring tensions. Morning Cleaning is considered as a Duchampian delay in relation to the politics of modernist glass architecture in Wall's Kammerspiel essay, and as a ,countermonument' to the reconstructed pavilion as fetish, emptied of social meaning and the traumatic history of modernity. [source] Commercializing lignocellulosic bioethanol: technology bottlenecks and possible remediesBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 1 2010Saumita Banerjee Abstract With diminishing oil supplies and growing political instability in oil-producing nations, the world is facing a major energy threat which needs to be solved by virtue of alternative energy sources. Bioethanol has received considerable attention in the transportation sector because of its utility as an octane booster, fuel additive, and even as neat fuel. Brazil and the USA have been producing ethanol on a large scale from sugarcane and corn, respectively. However, due to their primary utility as food and feed, these crops cannot meet the global demand for ethanol production as an alternative transportation fuel. Lignocellulosic biomass is projected as a virtually eternal raw material for fuel ethanol production. The main bottleneck so far has been the technology concerns, which do not support cost-effective and competitive production of lignocellulosic bioethanol. This review sheds light on some of the practical approaches that can be adopted to make the production of lignocellulosic bioethanol economically attractive. These include the use of cheaper substrates, cost-effective pre-treatment techniques, overproducing and recombinant strains for maximized ethanol tolerance and yields, improved recovery processes, efficient bioprocess integration, economic exploitation of side products, and energy and waste minimization. An integrated and dedicated approach can help in realizing large-scale commercial production of lignocellulosic bioethanol, and can contribute toward a cleaner and more energy efficient world. Copyright © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] FC03.3 Identification of subjects with atopic dermatitis in questionnaire studiesCONTACT DERMATITIS, Issue 3 2004Karen Frydendall Jepsen The performances of three different questions from The Nordic Occupational Skin Questionnaire (NOSQ-2002) were compared with respect to their ability to identify subjects with atopic dermatitis. NOSQ-2002 was used in an intervention study on the prevention of work related skin diseases among gut cleaners. The questions were: "Have you ever had an itchy rash that has been coming and going for at least 6 months, and at sometime has affected skin creases?"(A1), "Have you ever had eczema on the fronts of the elbow or behind the knees?"(S5a), and "Have you ever had "childhood" eczema?"(S5b). Question A1 is the single UK-working party question on atopic dermatitis; questions S5a & S5b are national atopic dermatitis questions previously used in different Nordic studies. A total of 255 of 622 (41%) gut cleaners answered "yes" to question A1. Questions S5a and S5b gave rise to 14% and 5% positive answers, respectively. The high frequency of positive answers to question A1 could be due to the occupational exposure of gut cleaners. Their working environment is wet and often involves both forearms and hands, hence often leading to eczema of elbow creases. In conclusion, compared to other Danish studies the UK question seems to lead to over-reporting. Question S5a seems to give a reliable frequency of atopic dermatitis in adult populations at risk for work-related skin diseases. [source] FS13.2 Intervention on work-related skin problems among gut cleanersCONTACT DERMATITIS, Issue 3 2004Mari-Ann Flyvholm Work-related skin problems are frequent in the food processing industry. A randomised intervention study with a one-year follow up was carried out among gut cleaners in order to prevent work-related skin problems due to wet work. The effects of the intervention were primarily measured by telephone interviews using questionnaires based on a standardized questionnaire for work-related skin diseases and exposure (NOSQ-2002).* The intervention activities included an evidence-based prevention program and an evidence-based method for implementation. Six of the 18 participating departments were randomly assigned to the intervention group and the remaining 12 departments to the comparison group. A total of 644 employees responded in the baseline interview and 622 in the follow-up interview carried out a year later. The participation rates were 87,5% and 71,6% respectively. Among the 495 participants answering in both interviews the frequency of eczema on hands or forearms within the past 3 months was reduced significantly by more than 25% in the intervention departments. A minor increase was observed in the comparison departments. This study has shown that even in jobs without the possibility to reduce high exposure to wet work work-related skin problems can be reduced by proper preventive measures. *) Susitaival P, Flyvholm M-A, Meding B, Kanerva L, Lindberg M, Svensson Å, Ólafsson JH. Contact Dermatitis 2003;49:70,76. [source] | ||||||||||||||||||||||||||||