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Entrapment: an important mechanism to explain the shortwave 3D radiative effect of clouds
Several mechanisms have previously been proposed to explain differences between the shortwave reflectance of realistic cloud scenes computed using the 1D independent column approximation (ICA) and 3D solutions of the radiative transfer equation. When the sun is low in the sky, interception of sunlight by cloud sides tends to increase reflectance relative to ICA estimates that neglect this effect. When the sun is high, 3D radiative transfer tends to make clouds less reflective, which we argue is explained by the mechanism of âentrapmentâ whereby horizontal transport of radiation beneath a cloud layer increases the chances, relative to the ICA, of light being absorbed by cloud or the surface. It is especially important for multilayered cloud scenes. We describe modifications to the previously described Speedy Algorithm for Radiative Transfer through Cloud Sides (SPARTACUS) to represent different entrapment assumptions, and test their impact on 65 contrasting scenes from a cloud-resolving model. When entrapment is represented explicitly via a calculation of the mean horizontal distance traveled by reflected light, SPARTACUS predicts a mean â3D radiative effectâ (the difference in top-of-atmosphere irradiances between 3D and ICA calculations) of 8.1 W mâ2 for overhead sun. This is within 2% of broadband Monte Carlo calculations on the same scenes. The importance of entrapment is highlighted by the finding that the extreme assumptions in SPARTACUS of âzero entrapmentâ and âmaximum entrapmentâ lead to corresponding mean 3D radiative effects of 1.7 and 19.6 W mâ2, respectively
Designing and Evaluating Interventions to Halt the Transmission of Tuberculosis.
To reduce the incidence of tuberculosis, it is insufficient to simply understand the dynamics of tuberculosis transmission. Rather, we must design and rigorously evaluate interventions to halt transmission, prioritizing those interventions most likely to achieve population-level impact. Synergy in reducing tuberculosis transmission may be attainable by combining interventions that shrink the reservoir of latent Mycobacterium tuberculosis infection (preventive therapy), shorten the time between disease onset and treatment initiation (case finding and diagnosis), and prevent transmission in key settings, such as the built environment (infection control). In evaluating efficacy and estimating population-level impact, cluster-randomized trials and mechanistic models play particularly prominent roles. Historical and contemporary evidence suggests that effective public health interventions can halt tuberculosis transmission, but an evidence-based approach based on knowledge of local epidemiology is necessary for success. We provide a roadmap for designing, evaluating, and modeling interventions to interrupt the process of transmission that fuels a diverse array of tuberculosis epidemics worldwide
Stratigraphic signature of the late Palaeozoic Ice Age in the Parmeener Supergroup of Tasmania, SE Australia, and inter-regional comparisons
Recent research in eastern Australia has established that rather than being a single, long-lived epoch, the late Palaeozoic Ice Age comprised a series of glacial intervals each 1â8 million years in duration, separated by non-glacial intervals of comparable duration. In order to test whether the glacial events recognized in New South Wales and Queensland have broader extent, we conducted a reappraisal of the Parmeener Supergroup of Tasmania, southeast Australia. A facies analysis of the Pennsylvanian to Permian section was carried out, allowing rationalization of the succession into four recurrent facies associations: a) glacigenic facies association, restricted to the basal Pennsylvanian/earliest Permian Wynyard Formation and correlatives, b) glacially/cold climate-influenced to open marine shelf facies association, which accounts for large parts of the Permian succession, c) deltaic facies association, which specifically describes the Lower Permian âLower Freshwater Sequenceâ interval, and d) fluvial to estuarine facies association, which specifically addresses the Upper Permian Cygnet Coal Measures and correlatives. Indicators of sediment accumulation under glacial influence and cold climate are restricted to four discrete stratigraphic intervals, all of which indicate that glaciation was temperate in nature. The lowermost of these, incorporating the basal Wynyard Formation and its correlatives, and overlying Woody Island Formation, shows evidence of proximal glacial influence (subglacial, grounding-line fan and ?fjordal facies), and is likely a composite of one or more Pennsylvanian glacial event(s) and an earliest Permian (Asselian) glacial. The second, of late Sakmarian to early Artinskian age, comprises an initial more proximal ice-influenced section and an overlying more distal ice-influenced interval. The third (Kungurian to Roadian) and fourth (Capitanian) intervals are both distal glacimarine records. The four intervals are of comparable age to glacials P1âP4, respectively, recognized in New South Wales and Queensland (notwithstanding apparent discrepancies of \u3c 2 million years in age), and display similar facies characteristics and vertical contrasts to those intervals. Accordingly, it is concluded that the late Palaeozoic stratigraphy of Tasmania preserves a glacial/cold climate record correlatable to that of mainland eastern Australia, lending support to the hypothesis that these events were widespread across this portion of Gondwana
Fast determination of thiacloprid by photoinduced chemiluminescence
This paper was published in Applied Spectroscopy and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/as/abstract.cfm?URI=as-68-6-642. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.A new and sensitive application of the chemiluminescence detection has been developed for the determination of the pesticide thiacloprid in water. It was based on the on-line photoreaction of thiacloprid in basic medium, with quinine acting as sensitizer of the chemiluminescent response; Cerium (IV) in sulfuric acid medium was used as oxidant. A high automation and reproducibility was provided by a flow injection analysis (FIA) manifold. The validation of the method was performed in terms of selectivity, linearity, LOD, precision and accuracy. Liquid chromatography with UV detection was used as reference for mineral, tap, ground and spring water samples. The proposed method is fast (throughput of 130 h-1), sensitive (LOD of 0.8 ng mL-1 without preconcentration steps and 0.08 ng mL-1 with solid phase extraction (SPE)), low-cost and possible to couple with separative methods for the simultaneous determination of other pesticides. The enhanced chemiluminescence intensity was linear with thiacloprid concentration over the (2-80) and (80-800) ng mL-1 ranges. A possible reaction mechanism is also discussed.The authors thank the Ministerio de Educacion y Ciencia of Spain and the Fondo Europeo de Desarrollo Regional for financial support, Project CTM2006-11991.CatalĂĄ Icardo, M.; LĂłpez Paz, JL.; PĂ©rez Plancha, LM. (2014). Fast determination of thiacloprid by photoinduced chemiluminescence. Applied Spectroscopy. 68(6):642-648. https://doi.org/10.1366/13-07330S642648686Tomizawa, M., & Casida, J. E. (2005). NEONICOTINOID INSECTICIDE TOXICOLOGY: Mechanisms of Selective Action. Annual Review of Pharmacology and Toxicology, 45(1), 247-268. doi:10.1146/annurev.pharmtox.45.120403.095930Tapparo, A., Giorio, C., SoldĂ , L., Bogialli, S., Marton, D., Marzaro, M., & Girolami, V. (2012). UHPLC-DAD method for the determination of neonicotinoid insecticides in single bees and its relevance in honeybee colony loss investigations. Analytical and Bioanalytical Chemistry, 405(2-3), 1007-1014. doi:10.1007/s00216-012-6338-3Tennekes, H. A., & SĂĄnchez-Bayo, F. (2013). The molecular basis of simple relationships between exposure concentration and toxic effects with time. Toxicology, 309, 39-51. doi:10.1016/j.tox.2013.04.007Peña, A., RodrĂguez-LiĂ©bana, J. A., & Mingorance, M. D. (2011). Persistence of two neonicotinoid insecticides in wastewater, and in aqueous solutions of surfactants and dissolved organic matter. Chemosphere, 84(4), 464-470. doi:10.1016/j.chemosphere.2011.03.039Di Muccio, A., Fidente, P., Barbini, D. A., Dommarco, R., Seccia, S., & Morrica, P. (2006). Application of solid-phase extraction and liquid chromatographyâmass spectrometry to the determination of neonicotinoid pesticide residues in fruit and vegetables. Journal of Chromatography A, 1108(1), 1-6. doi:10.1016/j.chroma.2005.12.111Fidente, P., Seccia, S., Vanni, F., & Morrica, P. (2005). Analysis of nicotinoid insecticides residues in honey by solid matrix partition clean-up and liquid chromatographyâelectrospray mass spectrometry. Journal of Chromatography A, 1094(1-2), 175-178. doi:10.1016/j.chroma.2005.09.012Seccia, S., Fidente, P., Barbini, D. A., & Morrica, P. (2005). Multiresidue determination of nicotinoid insecticide residues in drinking water by liquid chromatography with electrospray ionization mass spectrometry. Analytica Chimica Acta, 553(1-2), 21-26. doi:10.1016/j.aca.2005.08.006Pareja, L., MartĂnez-Bueno, M. J., Cesio, V., Heinzen, H., & FernĂĄndez-Alba, A. R. (2011). Trace analysis of pesticides in paddy field water by direct injection using liquid chromatographyâquadrupole-linear ion trap-mass spectrometry. Journal of Chromatography A, 1218(30), 4790-4798. doi:10.1016/j.chroma.2011.02.044Seccia, S., Fidente, P., Montesano, D., & Morrica, P. (2008). Determination of neonicotinoid insecticides residues in bovine milk samples by solid-phase extraction clean-up and liquid chromatography with diode-array detection. Journal of Chromatography A, 1214(1-2), 115-120. doi:10.1016/j.chroma.2008.10.088Wang, W., Li, Y., Wu, Q., Wang, C., Zang, X., & Wang, Z. (2012). Extraction of neonicotinoid insecticides from environmental water samples with magnetic graphene nanoparticles as adsorbent followed by determination with HPLC. Analytical Methods, 4(3), 766. doi:10.1039/c2ay05734dBi, X., & Yang, K.-L. (2009). On-Line Monitoring Imidacloprid and Thiacloprid in Celery Juice Using Quartz Crystal Microbalance. Analytical Chemistry, 81(2), 527-532. doi:10.1021/ac801786aGĂĄmiz-Gracia, L., GarcıÌa-Campaña, A. M., Soto-Chinchilla, J. J., Huertas-PĂ©rez, J. F., & GonzĂĄlez-Casado, A. (2005). Analysis of pesticides by chemiluminescence detection in the liquid phase. TrAC Trends in Analytical Chemistry, 24(11), 927-942. doi:10.1016/j.trac.2005.05.009Roda, A., & Guardigli, M. (2011). Analytical chemiluminescence and bioluminescence: latest achievements and new horizons. Analytical and Bioanalytical Chemistry, 402(1), 69-76. doi:10.1007/s00216-011-5455-8Du, J., & Li, H. (2010). Sensitive Chemiluminescence Determination of Thirteen Cephalosporin Antibiotics with LuminolâCopper(II) Reaction. Applied Spectroscopy, 64(10), 1154-1159. doi:10.1366/000370210792973613Li, Y., Li, Y., & Yang, Y. (2011). Flow-Injection Chemiluminescence Determination of Lisinopril Using LuminolâKMnO4 Reaction Catalyzed by Silver Nanoparticles. Applied Spectroscopy, 65(4), 376-381. doi:10.1366/10-06115CatalĂĄ-Icardo, M., LĂłpez-Paz, J. L., Choves-BarĂłn, C., & Peña-BĂĄdena, A. (2012). Native vs photoinduced chemiluminescence in dimethoate determination. Analytica Chimica Acta, 710, 81-87. doi:10.1016/j.aca.2011.10.043Mestre, Y. F., Zamora, L. L., & Calatayud, J. M. (2001). Flow-chemiluminescence: a growing modality of pharmaceutical analysis. Luminescence, 16(3), 213-235. doi:10.1002/bio.608Lara, F. J., GarcĂa-Campaña, A. M., & Aaron, J.-J. (2010). Analytical applications of photoinduced chemiluminescence in flow systemsâA review. Analytica Chimica Acta, 679(1-2), 17-30. doi:10.1016/j.aca.2010.09.001Icardo, M. C., & Calatayud, J. M. (2008). Photo-Induced Luminescence. Critical Reviews in Analytical Chemistry, 38(2), 118-130. doi:10.1080/10408340802039609RICART, I., ANTONFOS, G., DUART, M., MATEO, J., ZAMORA, L., & CALATAYUD, J. (2007). Theoretical prediction of the photoinduced chemiluminescence of pesticides. Talanta, 72(2), 378-386. doi:10.1016/j.talanta.2006.10.048AbramoviÄ, B. F., BaniÄ, N. D., & Ć ojiÄ, D. V. (2010). Degradation of thiacloprid in aqueous solution by UV and UV/H2O2 treatments. Chemosphere, 81(1), 114-119. doi:10.1016/j.chemosphere.2010.07.016Icardo, M. (2003). FI-on line photochemical reaction for direct chemiluminescence determination of photodegradated chloramphenicol. Talanta, 60(2-3), 405-414. doi:10.1016/s0039-9140(03)00074-2Zhao, Y., Baeyens, W. R. G., Zhang, X., Calokerinos, A. C., Nakashima, K., & Der Weken, G. V. (1997). Chemiluminescence Determination of Tiopronin by Flow Injection Analysis Based on Cerium(IV) Oxidation Sensitized by Quinine. The Analyst, 122(2), 103-106. doi:10.1039/a605703iZhang, Z., Baeyens, W. R. G., Zhang, X., Zhao, Y., & Van Der Weken, G. (1997). Chemiluminescence detection coupled to liquid chromatography for the determination of penicillamine in human urine. Analytica Chimica Acta, 347(3), 325-332. doi:10.1016/s0003-2670(97)00171-2CapitĂÂĄn-Vallvey, L. (2000). Chemiluminescence determination of sodium 2-mercaptoethane sulfonate by flow injection analysis using cerium(IV) sensitized by quinine. Talanta, 51(6), 1155-1161. doi:10.1016/s0039-9140(00)00291-5NIE, L., MA, H., SUN, M., LI, X., SU, M., & LIANG, S. (2003). Direct chemiluminescence determination of cysteine in human serum using quinineâCe(IV) system. Talanta, 59(5), 959-964. doi:10.1016/s0039-9140(02)00649-5Lakowicz, J. R. (Ed.). (2006). Principles of Fluorescence Spectroscopy. doi:10.1007/978-0-387-46312-4Lookabaugh, M., & Krull, I. S. (1988). Determination of nitrite and nitrate by reversed-phase high-performance liquid chromatography using on-line post-column photolysis with ultraviolet absorbance and electrochemical detection. Journal of Chromatography A, 452, 295-308. doi:10.1016/s0021-9673(01)81454-0GĂłmez-Benito, C., Meseguer-Lloret, S., & Torres-Cartas, S. (2013). Sensitive determination of Fenamiphos in water samples by flow injection photoinduced chemiluminescence. International Journal of Environmental Analytical Chemistry, 93(2), 152-165. doi:10.1080/03067319.2012.663755CATALĂ-ICARDO, M., LĂPEZ-PAZ, J. L., & PEĂA-BĂDENA, A. (2011). FI-photoinduced Chemiluminescence Method for Diuron Determination in Water Samples. Analytical Sciences, 27(3), 291. doi:10.2116/analsci.27.291Hamilton, D. J., Ambrus, Ă., Dieterle, R. M., Felsot, A. S., Harris, C. A., Holland, P. T., ⊠Wong, S.-S. (2003). Regulatory limits for pesticide residues in water (IUPAC Technical Report). Pure and Applied Chemistry, 75(8), 1123-1155. doi:10.1351/pac20037508112
School violence, school differences and school discourses
This article highlights one strand of a study which investigated the concept of the violenceresilient school. In six inner-city secondary schools, data on violent incidents in school and violent crime in the neighbourhood were gathered, and compared with school practices to minimise violence, accessed through interviews. Some degree of association between the patterns of behaviour and school practices was found: schools with a wider range of wellconnected practices seemed to have less difficult behaviour. Interviews also showed that the different schools had different organisational discourses for construing school violence, its possible causes and the possible solutions. Differences in practices are best understood in connection with differences in these discourses. Some of the features of school discourses are outlined, including their range, their core metaphor and their silences. We suggest that organisational discourse is an important concept in explaining school effects and school differences, and that improvement attempts could have clearer regard to this concept
Advanced InSAR atmospheric correction: MERIS/MODIS combination and stacked water vapour models
A major source of error for repeat-pass Interferometric Synthetic Aperture Radar (InSAR) is the phase delay in radio signal propagation through the atmosphere (especially the part due to tropospheric water vapour). Based on experience with the Global Positioning System (GPS)/Moderate Resolution Imaging Spectroradiometer (MODIS) integrated model and the Medium Resolution Imaging Spectrometer (MERIS) correction model, two new advanced InSAR water vapour correction models are demonstrated using both MERIS and MODIS data: (1) the MERIS/MODIS combination correction model (MMCC); and (2) the MERIS/MODIS stacked correction model (MMSC). The applications of both the MMCC and MMSC models to ENVISAT Advanced Synthetic Aperture Radar (ASAR) data over the Southern California Integrated GPS Network (SCIGN) region showed a significant reduction in water vapour effects on ASAR interferograms, with the root mean square (RMS) differences between GPS- and InSAR-derived range changes in the line-of-sight (LOS) direction
decreasing from ,10mm before correction to ,5mm after correction, which is similar to the GPS/MODIS integrated and MERIS correction models. It is expected that these two advanced water vapour correction models can expand the application of MERIS and MODIS data for InSAR atmospheric correction. A simple but effective approach has been developed to destripe Terra MODIS images contaminated by radiometric calibration errors. Another two limiting factors on the MMCC and MMSC models have also been investigated in this paper: (1) the impact of the time difference between MODIS and SAR data; and (2) the frequency of cloud-free conditions at the global scale
Yield stress, heterogeneities and activated processes in soft glassy materials
The rheological behavior of soft glassy materials basically results from the
interplay between shearing forces and an intrinsic slow dynamics. This
competition can be described by a microscopic theory, which can be viewed as a
nonequilibrium schematic mode-coupling theory. This statistical mechanics
approach to rheology results in a series of detailed theoretical predictions,
some of which still awaiting for their experimental verification. We present
new, preliminary, results about the description of yield stress, flow
heterogeneities and activated processes within this theoretical framework.Comment: Paper presented at "III Workshop on Non Equilibrium Phenomena...",
Pisa 22-27 Sep. 200
Wigs, disguises and child's play : solidarity in teacher education
It is generally acknowledged that much contemporary education takes place within a dominant audit culture, in which accountability becomes a powerful driver of educational practices. In this culture both pupils and teachers risk being configured as a means to an assessment and target-driven end: pupils are schooled within a particular paradigm of education. The article discusses some ethical issues raised by such schooling, particularly the tensions arising for teachers, and by implication, teacher educators who prepare and support teachers for work in situations where vocational aims and beliefs may be in in conflict with instrumentalist aims. The article offers De Certeauâs concept of âla perruqueâ to suggest an opening to playful engagement for human ends in education, as a way of contending with and managing the tensions generated. I use the concept to recover a concept of solidarity for teacher educators and teachers to enable ethical teaching in difficult times
Prospective, double-blind, placebo-controlled randomized trial of cimetidine in gastric cancer
Cimetidine is thought to inhibit suppressor T-lymphocyte function and preliminary evidence from a randomized trial indicated that it might prolong survival for patients with operable and inoperable gastric cancer. The British Stomach Cancer Group conducted a randomized, double-blind, placebo-controlled trial examining the effects of cimetidine (400 mg or 800 mg twice a day) on the survival of patients with early (stages I, II and III: n = 229) and advanced (stages IVa and IVb: n = 201) gastric cancer. The primary end point was death. A total of 442 patients were randomized by 59 consultants in 39 hospitals between February 1990 and March 1995. Log-rank survival analysis was used to assess differences between the groups. Three hundred and forty patients died during the study: 166 (49%) in the cimetidine treatment groups and 174 (51%) in the placebo groups. Median survival for patients receiving cimetidine was 13 months (95% confidence interval (CI) 9â16 months) and 11 months in the placebo arm (95% CI 9â14 months). There was no significant difference in survival between the two treatment groups (P = 0.42) or between different doses of cimetidine tablets (P = 0.46). Five-year survival of those patients randomized to cimetidine was 21% compared to 18% for those patients randomized to placebo. Cimetidine at a dose of 400 mg or 800 mg twice a day does not have a significant influence on the survival of patients with gastric cancer compared to placebo. © 1999 Cancer Research Campaig
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