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Terms modified by Very Important Selected AbstractsSurvey of the pre-school child health surveillance programme in SwedenACTA PAEDIATRICA, Issue 2000R Kornfält A survey of the programme for developmental surveillance in the Child Health Centres (CHCs) in Sweden was performed using a questionnaire administered to the Chief Medical Officers (CMO) of the Child Health Services. The questionnaire asked about methods used for auditory examination, developmental surveillance and identification of disturbances in mother-child interaction. Activities for health promotion concerning breastfeeding, non-smoking and allergy prevention were also queried. Thirty-four CMOs representing 1731 CHCs and 645000 children answered the questionnaire. The reply rate was 81%. Various methods of auditory examination are offered all infants and children in Sweden. The national guidelines for health supervision are followed fairly closely by all. Screening for disturbances in attention, motor development and perception (DAMP) is performed by all but four districts, with various methods, resources and degrees of co-operation with school health services. Support in mother-child interaction is considered very important and new methods to identify and treat disturbances are gradually introduced. Breastfeeding is encouraged; breast milk is the main source of food for 67% of babies at 4 mo of age. Activities to stop or diminish use of tobacco are ongoing everywhere, as are programmes to identify children at risk of developing allergies and for allergy prevention. Thus, the Child Health Services maintain a high standard and are ambitious about introducing new methods and ideas. [source] Experiments on robustness and deception in a coalition formation modelCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2006M. V. Belmonte Abstract In the last few years coalition formation algorithms have been proposed as a possible way of modeling autonomous agent cooperation in multi-agent systems. This work is based on a previously proposed coalition formation model founded on game theory for a class of task-oriented problems that guarantees an optimum task allocation and a stable profit division. In this paper we study two properties of the model that are very important for application in real-life scenarios: robustness and tolerance to an agent's misbehavior. First, we study the robustness of this model as regards the effect the agent's failure has on the resultant profits of the coalition formation. Secondly, we also study the coalition formation model in the presence of misbehaving agents. Agents have some kind of execution autonomy, and they can deceive or mislead each other when they reveal their information, if they believe this will give them more profits. Copyright © 2005 John Wiley & Sons, Ltd. [source] How to determine the number of inner-sphere water molecules in Lanthanide(III) complexes by 17O NMR spectroscopy.CONTRAST MEDIA & MOLECULAR IMAGING, Issue 2 2007A technical note Abstract Lanthanide(III) complexes of polyaminocarboxylates are widely used in MRI as contrast agents. The paramagnetic properties of the metal ion contribute to the increase of 1H relaxation rates, while the chelate offers a stable binding with the metal. The number of water molecules, coordinated directly to the Ln(III) ion, is very important for the relaxivity and, thus, the efficacy of these contrast agents. Here, we describe convenient methods to determine this parameter by measurement of Ln(III)-induced shifts of the water 17O NMR resonance. Copyright © 2007 John Wiley & Sons, Ltd. [source] Micronization of the officinal component baicalin by SEDS-PA processCRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2007Wen Zhi He Abstract Application of micronizing technologies in processing Chinese herbal medicines is very important to improve the forms of prepared Chinese herbal medicines and promote their therapeutic efficacy. Baicalin, a major active component of the typical Chinese herb medicine Scullateria baicallensis Georgi, was micronized using the Solution Enhanced Dispersion by Supercritical fluids though Prefilming Atomization (SEDS-PA) process with the aim of evaluating the efficiency of applying supercritical fluid precipitation technologies in Chinese herb medicine. This study has shown that acicula or rod-like baicalin crystals with Particle Size (PS) of about 20×100 ,m were successfully micronized by the SEDS-PA process to long rod-like, twisted fiber-like or fibrous net-like microparticles with PS of 0.1-2.2 ,m in width within the range of experiments performed. It was found that a substantial reduction of baicalin microparticles' sizes could lead to a marked increase of adhesions among them and subsequent microparticles agglomeration. With the increase of supercritical CO2 flow rate and the decrease of solution concentration and solution flow rate, smaller and much more agglomerated microparticles were obtained. Increasing pressure led to formation of smaller microparticles. A larger tendency of particles agglomeration was produced at a higher temperature. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Raman spectroscopic and X-ray investigation of stressed states in diamond-like carbon filmsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 1-2 2005R. Krawietz Abstract The non-destructive characterization of intrinsic stress is very important to evaluate the reliability of devices based on diamond-like carbon (DLC) films. Whereas the only requirement for the X-ray diffraction method is a crystalline state of specimen, Raman spectroscopic stress analysis is restricted to materials showing intensive and sharp Raman peaks. On the other hand, Raman spectroscopy offers the possibility to measure stress profiles with lateral resolution of about 1 micron. The results of stress measurements in DLC films using both X-ray diffraction and Raman spectroscopy are found in very good correspondence. Mean stress in carbon films consisting of very small crystallites on silicon substrates has been determined by measuring and fitting the stress profiles in the substrate near artificial vertical film edges. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Environmental Risk Factors Predisposing to the Development of Basal Cell CarcinomaDERMATOLOGIC SURGERY, Issue 2004Malgorzata Zak-Prelich MD Background. Basal cell carcinomas (BCCs) are the most common malignancies in white people. The incidence varies depending on the region of the world, with the highest rate of 1% to 2% per year noted in Australia. It is estimated that BCC incidence increases by 5% annually. An increasing incidence of BCC is in line with the changes in the living style and exposure to various environmental factors. Objective. To present the environmental factors that may influence the development of BCCs. The influence of ultraviolet radiation exposure alone and in connection with immunosuppression, smoking, occupational factors, as well as arsenic and ionizing radiation exposure, was described. Conclusion. BCC is a very complex disease, with many factors influencing its development. Environmental factors are very important for the prevalence of BCC, and most of them can be avoided. The exposure to ultraviolet radiation is undoubtedly of great risk; therefore, the national campaigns against aggressive, seasonal sun exposure, especially in children and adolescents, as well as using sunscreens, are of great value in the fight against BCC development. [source] Reduced accommodative function in dyskinetic cerebral palsy: a novel management strategyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2000Linda M Ross MBCh B MRCP MRCPCH A9-year-old boy with dyskinetic cerebral palsy secondary to neonatal encephalopathy is described. He presented with blurring of near vision which had begun to impact on his school work. Objective assessment of accommodation showed that very little was present, although convergence was almost normal. The near-vision symptoms were completely removed and reading dramatically improved with the provision of varifocal spectacles. Varifocal lenses provide an optimal correction for far, intermediate (i.e. for computer screens), and near distances (i.e. for reading). Managing this type of patient with varifocal spectacles has not been previously reported. It is clearly very important to prescribe an optimal spectacle correction to provide clear vision to optimize learning. [source] ENDOSCOPIC SUBMUCOSAL DISSECTION FOR ESOPHAGEAL SQUAMOUS CELL NEOPLASMSDIGESTIVE ENDOSCOPY, Issue 2 2009Mitsuhiro Fujishiro Endoscopic submucosal dissection (ESD) has gradually gained acceptance as one of the standard treatments for early esophageal cancer, as well as for early gastric cancer in Japan, but standardization of the knowledge is still incomplete. The final goal to perform ESD is not to resect the lesion in an en bloc fashion, but to save the patient from esophageal cancer-related death. Thus, the indications should be considered based on the entire patient, not just the target lesion itself, and pre-, peri- and postoperative management of the patient is also very important, as well as technical aspects of ESD. In terms of the techniques of ESD, owing to refinement of the procedural strategy, invention of the devices, and the learning curve, acceptable safety and favorable middle-term efficacy have been obtained. We believe that ESD will become a standard treatment for early esophageal cancer not only in Japan but also worldwide in the near future. [source] Current management of esophageal perforation: 20 years experienceDISEASES OF THE ESOPHAGUS, Issue 4 2009A. Eroglu SUMMARY Esophageal perforations are surgical emergencies associated with high morbidity and mortality rates. No single strategy has been sufficient to deal with the majority of situations. We aim to postulate a therapeutic algorithm for this complication based on 20 years of experience and also on data from published literature. We performed a retrospective clinical review of 44 patients treated for esophageal perforation at our hospital between January 1989 and May 2008. We reviewed the characteristics of these patients, including age, gender, accompanying diseases, etiology of perforation, diagnosis, location, time interval between perforation and diagnosis, treatment of the perforation, morbidity, hospital mortality, and duration of hospitalization. Perforation occurred in the cervical esophagus in 14 patients (31.8%), thoracic esophagus in 18 patients (40.9%), and abdominal esophagus in 12 patients (27.3%). Management of the esophageal perforation included primary closure in 23 patients (52.3%), resection in 7 patients (15.9%), and nonsurgical therapy in 14 patients (31.8%). In the surgically treated group, the mortality rate was 3 of 30 patients (10%), and 2 of 14 patients (14.3%) in the conservatively managed group. Four of the 14 nonsurgical patients were inserted with covered self-expandable stents. The specific treatment of an esophageal perforation should be selected according to each individual patient. To date, the most effective treatment would appear to be operative management. With improvements in endoscopic procedures, the morbidity and mortality rates of esophageal perforations are significantly decreased. We suggest that minimally invasive techniques for the repair of esophageal perforations will be very important in the future treatment of this condition. [source] Evidence for repeated re-activation of old landslides under forestEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2009M. Van Den Eeckhaut Abstract Local reactivations of landslides in forests are rarely reported in landslide catalogues. The occurrence of hillslope sections with fresh morphological landslide features in forested old, deep-seated landslides, however, suggests that landslide reactivations are not restricted to residential areas. In this study, a dendrogeomorphological analysis of beech stands was used to investigate the periods of reactivation of a deep-seated rotational slide in the Koppenberg forest (Flemish Ardennes, Belgium). The relation to rainfall and the correspondence to landslide reactivations reported in a nearby built-up area were also analysed. A dendrometrical study preceding the dendrochronological analysis proved that, compared with the nearby reference site, trees on the Koppenberg forest landslide site were significantly more inclined and showed more knees, indicating that the landslide site has not stabilized yet. As the sampled trees are younger than the landslide, dendrochronology did not allow determination of the year in which the landslide was initiated, but analysis of two different tree ring width parameters (i.e. ring eccentricity and growth change) calculated for trees sampled on the Koppenberg landslide and the reference site proved to be of great help in determining the temporal sequence of landslide reactivation. During the past 80 years, several periods indicative of local reactivations (i.e. 1943,1945, 1949,1952, 1967,1970, 1972,1977, 1979,1981, 1988,1997) were found within the investigated landslide, but delineation of the spatial extent of the reactivations during these indicative periods was not straightforward. These periods generally correspond to years with above-average rainfall. Finally, the fact that at least 34% of the years indicative of reactivation of the Koppenberg forest landslide correspond to a year in which a landslide reactivation was reported in the Flemish Ardennes suggests that in built-up areas, apart from anthropogenic interventions, natural triggering factors remain very important. Copyright © 2009 John Wiley & Sons, Ltd. [source] Modelling increased soil cohesion due to roots with EUROSEMEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2008S. De Baets Abstract As organic root exudates cause soil particles to adhere firmly to root surfaces, roots significantly increase soil strength and therefore also increase the resistance of the topsoil to erosion by concentrated flow. This paper aims at contributing to a better prediction of the root effects on soil erosion rates in the EUROSEM model, as the input values accounting for roots, presented in the user manual, do not account for differences in root density or root architecture. Recent research indicates that small changes in root density or differences in root architecture considerably influence soil erosion rates during concentrated flow. The approach for incorporating the root effects into this model is based on a comparison of measured soil detachment rates for bare and for root-permeated topsoil samples with predicted erosion rates under the same flow conditions using the erosion equation of EUROSEM. Through backwards calculation, transport capacity efficiencies and corresponding soil cohesion values can be assessed for bare and root-permeated topsoils respectively. The results are promising and present soil cohesion values that are in accordance with reported values in the literature for the same soil type (silt loam). The results show that grass roots provide a larger increase in soil cohesion as compared with tap-rooted species and that the increase in soil cohesion is not significantly different under wet and dry soil conditions, either for fibrous root systems or for tap root systems. Power and exponential relationships are established between measured root density values and the corresponding calculated soil cohesion values, reflecting the effects of roots on the resistance of the topsoil to concentrated flow incision. These relationships enable one to incorporate the root effect into the soil erosion model EUROSEM, through adapting the soil cohesion input value. A scenario analysis shows that the contribution of roots to soil cohesion is very important for preventing soil loss and reducing runoff volume. The increase in soil shear strength due to the binding effect of roots on soil particles is two orders of magnitude lower as compared with soil reinforcement achieved when roots mobilize their tensile strength during soil shearing and root breakage. Copyright © 2008 John Wiley & Sons, Ltd. [source] Determination of bankfull discharge magnitude and frequency: comparison of methods on 16 gravel-bed river reachesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2006O. Navratil Abstract Bankfull discharge is identified as an important parameter for studying river morphology, sediment motion, flood dynamics and their ecological impacts. In practice, the determination of this discharge and its hydrological characteristics is not easy, and a choice has to be made between several existing methods. To evaluate the impact of the choice of methods, five bankfull elevation definitions and four hydrological characterizations (determination of duration and frequency of exceedance applied to instantaneous or mean daily data) were compared on 16 gravel-bed river reaches located in France (the catchment sizes vary from 10 km2 to 1700 km2). The consistency of bankfull discharge estimated at reach scale and the hydraulic significance of the five elevation definitions were examined. The morphological definitions (Bank Inflection, Top of Bank) were found more relevant than the definitions based on a geometric criterion. The duration of exceedance was preferred to recurrence intervals (partial duration series approach) because it is not limited by the independency of flood events, especially for low discharges like those associated with the Bank Inflection definition. On average, the impacts of the choice of methods were very important for the bankfull discharge magnitude (factor of 1·6 between Bank Inflection and Top of Bank) and duration of exceedance or frequency (respectively a factor 1·8 and 1·9 between mean daily and instantaneous discharge data). The choice of one combination of methods rather than another can significantly modify the conclusions of a comparative analysis in terms of bankfull discharge magnitude and its hydrological characteristics, so that one must be cautious when comparing results from different studies that use different methods. Copyright © 2006 John Wiley & Sons, Ltd. [source] Controls on modern alluvial fan processes in the central Alps, northern ItalyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2004Giovanni B. Crosta Abstract Alluvial fan development in Alpine areas is often affected by catastrophic sedimentary processes associated with extreme ,oods events, causing serious risks for people living on the fans. Hazard assessment in these areas depends on proper identi,cation of the dominant sedimentary processes on the fans. Data from a set of 209 alluvial fans from the central Alps of Italy are presented in this paper and analysed with the help of various statistical techniques (linear regression, principal components analysis, cluster analysis, discriminant analysis and logistic regression). First, we used modern sedimentary facies and historical records (,ood events since 15th century), to distinguish between the two dominant sedimentary processes on alluvial fans: debris ,ows and stream,ows. Then, in order to analyse the main controls on past and present fan processes, 36 morphological, geological and land-use variables were analysed. As with observations for arid-environment fans, catchment morphology is the most in,uential factor in the study area, whereas geology and land use are minor controls. The role of climatic change and landsliding within the catchments also seems to be very important and is discussed. Statistical techniques also help in differentiating groups of alluvial fans by sets of controlling factors, including stage and type of evolution. Finally, by using discriminant analysis and logistic regression, we classi,ed alluvial fans according to the dominant sedimentary process, with a success rate ranging between 75 and 92 per cent. Copyright © 2004 John Wiley & Sons, Ltd. [source] Emergency Medicine Residency Selection: Factors Influencing Candidate DecisionsACADEMIC EMERGENCY MEDICINE, Issue 6 2005Melissa DeSantis MD Abstract Background: Published information is limited regarding factors considered by emergency medicine resident candidates when selecting a residency program. Objective: To identify factors considered important by applicants when making decisions about residency programs. Methods: A self-administered survey questionnaire was mailed to all applicants who interviewed at the authors' emergency medicine residency program for the 2003,2004 match year. Results: Surveys were completed by 105 respondents (53% response rate). Factors were rank-ordered by the proportion of respondents who indicated that the factor was "very important" or "important" when selecting residency programs. The five most important factors were friendliness (95%), environment (87%), interview day (81%), academics (76%), and location (74%). Male applicants were more likely to consider the existence of a flight program important or very important (55%), compared with female applicants (33%, p < 0.05, chi-square). Older respondents (over the age of 30 years) were more likely to consider gender issues (16%, compared with 13%) and research (32%, compared with 20%) as important factors (p < 0.05, chi-square). Conclusions: Residency applicants indicated that the most important factors when selecting residency program(s) were friendliness, environment, interview day, academics, and location. [source] Is the matrix a sea?ECOLOGICAL ENTOMOLOGY, Issue 1 2005Habitat specificity in a naturally fragmented landscape Abstract., 1. Metapopulation and island biogeography theory assume that landscapes consist of habitat patches set in a matrix of non-habitat. If only a small proportion of species conform to the patch,matrix assumptions then metapopulation theory may only describe special cases rather than being of more general ecological importance. 2. As an initial step towards understanding the prevalence of metapopulation dynamics in a naturally fragmented landscape, the distribution of beetle species in three replicates of three habitat types was examined, including rainforest and eucalypt forest (the habitat patches), and buttongrass sedgeland (the matrix), in south-west Tasmania, Australia. 3. Ordination methods indicated that the buttongrass fauna was extremely divergent from the fauna of forested habitats. Permutation tests showed that the abundance of 13 of 17 commonly captured species varied significantly among habitats, with eight species confined to eucalypts or rainforest, and three species found only in buttongrass. Approximately 60% of species were confined to forested habitat implying that metapopulation theory has the potential to be very important in the forest,buttongrass landscape. 4. Although floristically the rainforest and eucalypts were extremely distinct, the beetle faunas from eucalypts and rainforests overlapped substantially. Therefore rainforest patches connected by eucalypt forest represent continuous habitat for most species. 5. Other studies report a wide range of values for the proportion of patch-specific species in fragmented landscapes. Understanding the environmental or historical conditions under which a high proportion of species become patch specialists would help to identify where spatial dynamic theory may be especially applicable, and where habitat loss and fragmentation poses the greatest threat to biodiversity. [source] Mortgage Terminations, Heterogeneity and the Exercise of Mortgage OptionsECONOMETRICA, Issue 2 2000Yongheng Deng As applied to the behavior of homeowners with mortgages, option theory predicts that mortgage prepayment or default will be exercised if the call or put option is ,in the money' by some specific amount. Our analysis: tests the extent to which the option approach can explain default and prepayment behavior; evaluates the practical importance of modeling both options simultaneously; and models the unobserved heterogeneity of borrowers in the home mortgage market. The paper presents a unified model of the competing risks of mortgage termination by prepayment and default, considering the two hazards as dependent competing risks that are estimated jointly. It also accounts for the unobserved heterogeneity among borrowers, and estimates the unobserved heterogeneity simultaneously with the parameters and baseline hazards associated with prepayment and default functions. Our results show that the option model, in its most straightforward version, does a good job of explaining default and prepayment, but it is not enough by itself. The simultaneity of the options is very important empirically in explaining behavior. The results also show that there exists significant heterogeneity among mortgage borrowers. Ignoring this heterogeneity results in serious errors in estimating the prepayment behavior of homeowners. [source] Greek Monetary Economics in Retrospect: The Adventures of the DrachmaECONOMIC NOTES, Issue 3 2005Sophia Lazaretou This paper enumerates the adventures of the drachma step by step, dividing its story into seven parts. Specifically, its main purpose is to present some historical perspective on the behaviour of the monetary and fiscal policies pursued in Greece during the period from the early 1830s until the introduction of the euro. For Greece, the lessons of historical experience are very important. Since the formation of the modern Greek state, government officials have striven , sometimes making hard efforts , to keep abreast of international monetary developments. This was because they understood that the participation of a peripheral, poor and inflation-prone country with a weak currency and an underdeveloped money market, like Greece of the time, in a monetary club of powerful economies could improve her international credit standing and imply important benefits in terms of exchange rate and monetary stability, and long-term foreign borrowing. [source] Educational production in EuropeECONOMIC POLICY, Issue 43 2005Ludger Wößmann SUMMARY Europe's schools Available data and recently developed estimation methods make it possible to assess school performance in terms of a production process, where ,inputs' of students, teachers, and resources are combined to create a very important ,output': the cognitive skills of students. This paper estimates the education production function using representative samples of middle-school students in 15 West European countries. The size of teaching classes is a particularly important feature of the educational production process because it can be relatively easily manipulated by policy makers. However, no statistically and economically significant class-size effect is detected by any of the evidence considered in this paper. The results suggest that, at least in the context of the resources and organizational structure of West European lower secondary education systems, expensive across-the-board reduction of class sizes is extremely unlikely to foster student learning. , Ludger Wößmann [source] Autonomous dispersed control system for independent micro gridELECTRICAL ENGINEERING IN JAPAN, Issue 1 2009Kensuke Kawasaki Abstract In this paper, we show an autonomous dispersed control system for independent micro grid of which performance has been substantiated in China by Shikoku Electric Power Co. and its subsidiary companies under the trust of NEDO (New Energy and Industrial Technology Development Organization). For the control of grid interconnected generators, the exclusive information line is very important to save fuel cost and maintain high frequency quality of the electric power supply, but it is relatively expensive in such small micro grids. We contrived an autonomous dispersed control system without any exclusive information line for dispatching control and adjusting supply control. We have confirmed through the substantiation project in China that this autonomous dispersed control system for an independent micro grid has a very satisfactory characteristic from the viewpoint of less fuel consumption and high electric quality. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 28,35, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20618 [source] Attitude control of planar end-effector and estimation of contact point using parallel mechanismELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 3 2008Ryogo Kubo Abstract Recently, may robots have been utilized in unknown environment, for example, slave robots of teleoperation systems, walking robots and so on. They are called environment-adaptive robots. It is very important for the environment-adaptive robots to contact stably and to recognize unknown environment. In this paper, a compliance controller of attitude of a planar end-effector is proposed to achieve stable contact with unknown environment. The robot utilized in this research has parallel mechanism as a whole, since the planar end-effector is supported by three arms. With the assumption that only face-to-point contact exists between the end-effector and unknown environment, an estimation method of the contact point without sensors is also proposed. Moreover, excessive stress is not exerted on the robots and the environments by means of the controller we propose, when the contact point is estimated. Our new approach of contact motion can be widely applied to the robots using parallel mechanism. The validity of the proposed method is shown by the numerical and experimental results. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(3): 28, 36, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10071 [source] Lectin-aided separation of circulating tumor cells and assay of their response to an anticancer drug in an integrated microfluidic deviceELECTROPHORESIS, Issue 18 2010Li Li Abstract Metastasis caused by the entry of circulating tumor cells (CTCs) into the bloodstream or lymphatic vessels is a major factor contributing to death in cancer patients. Separation of CTCs and studies on CTC,drug interactions are very important for prognostic and therapeutic implications of metastatic cancer. In this study, an integrated microfluidic device for CTC separation through the combination of lectin and microstructure is presented. This microfluidic device and lectin concanavalin A were utilized for the separation of K562 cells in whole blood samples. The results showed that the separation efficiency can reach 84%, which is much higher than that of an experiment without concanavalin A treatment. To further demonstrate the feasibility of this microfluidic device application in sequential studies after target cells were separated, the interactions of K562 cells and an anticancer drug, cytarabine, were also examined. After 6,h on-chip treatment with cytarabine, the viabilities of K562 cells were 85.29, 77.05, and 40% for drug concentration levels of 0.25, 0.5, and 1.0,g/L, respectively. This system can facilitate the rapid and efficient in vitro investigation of CTC separation and CTC-related studies. [source] Multiple-point electrochemical detection for a dual-channel hybrid PDMS-glass microchip electrophoresis deviceELECTROPHORESIS, Issue 19 2009Mario Castaño-Álvarez Abstract A new PDMS-based dual-channel MCE with multiple-point amperometric detection has been evaluated. Electrophoresis has been optimised in a single-channel device. Pretreatment with 0.1,M NaOH is very important for increasing and stabilising the EOF. The precision is adequate for a day's work in terms of both peak current and migration time. The RSD of the peak current for five successive signals was 1.9, 2.4 and 3.1% for dopamine, p- aminophenol and hydroquinone. RSD for the migration time was always less than 1.3%, which demonstrates the stability of the EOF and the possibility of running multiple experiments in the same microchip. The adequate inter-microchip precision as well as the rapid and simple manufacturing procedure indicates the disposable nature of the PDMS microchips. A dual-channel device with very simple multiple-point amperometric detection is proposed here. Elasticity of the PDMS allows removing the polymer slightly and aligning gold wires working electrodes. Injection can be performed from each of the sample reservoirs or from both simultaneously. The distance between the separation channels is critical for obtaining adequate signals as well as the introduction of a high-voltage electrode in the buffer reservoir. Simultaneous measurement of the same analytes in both channels is possible by applying the same potential. Moreover, since no cross-separation is produced, different analytes or samples can be simultaneously measured. [source] Rapid characterization of fatty alcohol ethoxylates by non-aqueous capillary electrophoresisELECTROPHORESIS, Issue 14 2008Mónica Arias Abstract Fatty alcohol ethoxylates (FAE) (a mixture of nonionic surfactants) have been characterized using NACE with UV detection. Phenyl polyurethane derivatives of these compounds were previously obtained by reaction with phenyl isocyanate. The derivatization reaction only requires microwave irradiation for 30,s (600,W). Phenyl polyurethanes were separated and characterized using a BGE containing a mixture of ammonium nitrate (15,mM), acetic acid (1.5%) and 9:1 v/v methanol/ACN. After optimization of the instrumental conditions for the separation, phenyl polyurethane compounds (formed from the corresponding FAE) with ethylene oxide numbers (EON) of 6 (certified standard and industrial samples), 7 and 10 (both as industrial samples), and 5.5 (microemulsion phase) were successfully separated and characterized. The properties of these FAE nonionic surfactants are very important in the petroleum industry, which requires characterization of the quality of the purchased materials as well as the final products in the microemulsion-oil-water stream process. This analytical objective has been achieved by the proposed NACE methods, allowing FAE to be distinguished from 5.5 to 10 EON with errors below 4%, and shows advantages against to HPLC methods. [source] System zones in capillary zone electrophoresis: Moving boundaries caused by freely migrating hydrogen ionsELECTROPHORESIS, Issue 2 2005Jozef L. Beckers Abstract We demonstrate that system zones (SZs) can be expected in background electrolytes (BGEs) with a low buffer capacity. The mobilities of this type of SZ (mSZ) could be determined by calculations both based on a mathematical model and by a simulation program. The values of mSZ are increasing for decreasing buffer capacities and lower concentrations of the BGEs. For completely unbuffered BGEs with a pH below 7, the mSZ reached values up to 350×10,9 m2V,1s,1. This value indicates that the existence of this type of SZ originates from migrating hydrogen ions. Although both the mathematical model and simulation program do not consider the influence of the pH of the sample solution, experiments have shown that the pH of the sample solution is also very important. The lower the pH of the sample solution, the larger the mSZ in a specific BGE for cationic SZs. Using completely unbuffered BGEs the hydrogen ions present in the original sample start to migrate freely through the capillary tube with the mobility of a single hydrogen ion and cause stepwise disturbances in the base line of the detector trace. It is remarkable that this type of SZ appears not to affect the electromigration dispersion (EMD) in a strong way and so far only dips could be obtained experimentally. [source] Debriefing critical incidents in the paediatric emergency department: Current practice and perceived needs in Australia and New ZealandEMERGENCY MEDICINE AUSTRALASIA, Issue 6 2009Theane Theophilos Abstract Anecdotally critical incident debriefing (CID) is an important topic for staff in paediatric ED. The present study aimed to determine current baseline CID practices and perceived needs of ED staff. A questionnaire regarding CID practice was circulated to all 13 Paediatric Research in Emergency Departments International Collaborative (PREDICT) sites in Australia and New Zealand (including all tertiary paediatric ED), and completed by 1 senior doctor and 1 senior nurse. All PREDICT sites participated (13 nurses, 13 doctors). Seventy per cent did not currently have a hospital protocol on debriefing and 90% did not have ED-specific guidelines. The most commonly debriefed topics were death of a patient, multi-trauma and sudden infant death syndrome, also ranked highest in importance for debriefing. The median reported debriefs per department were 4 per year (range 0,12), all conducted within a week of the CI with half within 24 h. ED workers most likely to be invited to the CID session were doctors, nurses and social workers (96%). Debriefing was mostly conducted internally (62%) and most likely facilitated by a doctor (81%) or nurse (54%). Debriefing addressed both clinical and emotional issues (89%) within the same session (69%). Debriefing was rated as very important, median of 8/10 by doctors and 10/10 by nurses. Almost 90% of those surveyed indicated that they would like a CID programme and guidelines for their department. Debriefing is perceived as important by senior ED clinicians, yet few ED have formalized guidelines or programmes. Best-practice guidelines should be developed. [source] Assessing sources of variability in measurement of ambient particulate matterENVIRONMETRICS, Issue 6 2001Michael J. Daniels Abstract Particulate matter (PM), a component of ambient air pollution, has been the subject of United States Environmental Protection Agency regulation in part due to many epidemiological studies examining its connection with health. Better understanding the PM measurement process and its dependence on location, time, and other factors is important for both modifying regulations and better understanding its effects on health. In light of this, in this paper, we will explore sources of variability in measuring PM including spatial, temporal and meteorological effects. In addition, we will assess the degree to which there is heterogeneity in the variability of the micro-scale processes, which may suggest important unmeasured processes, and the degree to which there is unexplained heterogeneity in space and time. We use Bayesian hierarchical models and restrict attention to the greater Pittsburgh (USA) area in 1996. The analyses indicated no spatial dependence after accounting for other sources of variability and also indicated heterogeneity in the variability of the micro-scale processes over time and space. Weather and temporal effects were very important and there was substantial heterogeneity in these effects across sites. Copyright © 2001 John Wiley & Sons, Ltd. [source] Reports of information and support needs of daughters and sisters of women with breast cancerEUROPEAN JOURNAL OF CANCER CARE, Issue 1 2003ASSOCIATE PROFESSOR , K. CHALMERS RN, MSC(A) The aim of this study was to describe the information and support needs of women who have primary relatives with breast cancer. The Information and Support Needs Questionnaire (ISNQ) was developed and revised from previous qualitative and pilot studies. The ISNQ addressed concepts of the importance of, and the degree to which, 29 information and support needs related to breast cancer had been met. The study sample consisted of 261 community-residing women who had mothers, sisters, or a mother and sister(s) with breast cancer. Data were collected using a mailed survey. In addition to the ISNQ, additional items addressed family and health history, breast self-care practices, perception of the impact of the relative's breast cancer and other variables. Also included were established and well-validated measures of anxiety and depression. The findings document women's priority information and support needs. The information need most frequently identified as very important was information about personal risk of breast cancer. Other highly rated needs addressed risk factors for breast cancer and early detection measures. Generally, the women perceived that their information and support needs were not well met. These findings illuminate needs of women for more information and support when they have close family relatives with breast cancer and opportunities for primary care providers to assist women in addressing their needs. [source] Photophysical and Photochemical Properties of Fluorinated and Nonfluorinated n -Propanol-Substituted Zinc PhthalocyaninesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2010lke Gürol Abstract The synthesis of symmetrical fluorinated and nonfluorinated zinc(II) phthalocyanine derivatives obtained from 4,5-dichlorophthalonitrile, 4-nitrophthalonitrile and 3-nitrophthalonitrile substituted with 2,2,3,3-tetrafluoro-1-propanol and n -propanol are described. The comparison of the photophysicochemical properties of fluorinated and nonfluorinated substituted zinc(II) phthalocyanines is reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H NMR and 19F NMR spectroscopy, electronic spectroscopy and mass spectra. The photophysical and photochemical properties of the compounds were studied in dimethyl sulfoxide (DMSO). The complexes were quenched with benzoquinone (BQ), and their fluorescence-quenching properties were investigated in the same solvent. The effects of the number of the substitution and the position on the photophysical and photochemical parameters of the zinc(II) phthalocyanines 1a,7a are also reported. Photophysical and photochemical properties of phthalocyanine complexes are very useful for photodynamic therapy (PDT) of cancer applications. In particular, high singlet-oxygen quantum yields are very important for Type II mechanisms. These complexes have good singlet-oxygen quantum yields and show potential as Type-II photosensitizers. [source] Stabilization of phytosterols in rapeseed oil by natural antioxidants during heatingEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 11 2009Dominik Kmiecik Abstract Antioxidants are substances that can reduce negative changes in fat. Many antioxidants are very effective during storage, but during heating they lose their properties. It is very important to find antioxidants that will be stable at high temperatures and protect fat throughout the entire frying process. The aim of this study was to estimate the effect of natural and synthetic antioxidants on changes in phytosterols of rapeseed oil during heating. Oil with antioxidants was heated at 180,°C for 4,h in a Rancimat® and in an Oxidograph®. Ethanol extract of rosemary, ethanol extract of green tea, and BHT were used in the study. The contents of phytosterols (sitosterol, campesterol, avenasterol, brassicasterol, stigmasterol) and oxyphytosterols (7,- and 7,-hydroxysterol, 5,,6,- and 5,,6,-epoxysterol, 7-ketosterol and triols) were estimated by gas chromatography. In all samples with antioxidants, a lower decrease of phytosterols and a lower increase of total oxyphytosterols were observed in comparison with the control sample (without antioxidant). The antioxidant effect depends on the type of the antioxidant and the heating conditions. The best results were observed in samples with natural antioxidants. BHT was a substance that protected phytosterols as well, but not as effectively as the other antioxidants. [source] Influence of filling fat type on praline products with nougat fillingEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 12 2007Biljana Pajin Abstract The aim of this research was to examine the composition and functional characteristics of three samples of commercial filling fat intended for the making of nougat fillings for confectionary products. The crystallization rate of the fats was measured under static conditions using the NMR technique and under dynamic conditions as well as using a rotational rheometer. The functional characteristics of the fats were estimated by means of sensory values of the prepared praline product. Under the static conditions, all investigated filling fats showed a fast crystallization rate (,2,4%/min). The sample with the highest lauric acid contents started to crystallize immediately (no induction period). The longest induction period was found for the sample with the lowest saturated fatty acid and trans fatty acid contents. During the crystallization under dynamic conditions, all investigated samples started to crystallize more rapidly (rapid viscosity increase) at practically the same temperature (,17,°C). Measuring solid fat content and viscosity are two approaches of determining the suitability of a filling fat to be used in pralines. Both measurements provide valuable information, and particularly viscosity build-up is very important from the view of production on factory scale. [source] | |||||||||||||||||||||||||||||||||||||