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Cumulative Amount (cumulative + amount)
Selected AbstractsAnalysis of historical landslide time series in the Emilia-Romagna region, northern ItalyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2010Mauro Rossi Abstract A catalogue of historical landslides, 1951,2002, for three provinces in the Emilia-Romagna region of northern Italy is presented and its statistical properties studied. The catalogue consists of 2255 reported landslides and is based on historical archives and chronicles. We use two measures for the intensity of landsliding over time: (i) the number of reported landslides in a day (DL) and (ii) the number of reported landslides in an event (Sevent), where an event is one or more consecutive days with landsliding. From 1951,2002 in our study area there were 1057 days with 1 , DL ,?45 landslides per day, and 596 events with 1 , Sevent , 129 landslides per event. In the first set of analyses, we find that the probability density of landslide intensities in the time series are power-law distributed over at least two-orders of magnitude, with exponent of about ,2·0. Although our data is a proxy for landsliding built from newspaper reports, it is the first tentative evidence that the frequency-size of triggered landslide events over time (not just the landslides in a given triggered event), like earthquakes, scale as a power-law or other heavy-tailed distributions. If confirmed, this could have important implications for risk assessment and erosion modelling in a given area. In our second set of analyses, we find that for short antecedent rainfall periods, the minimum amount of rainfall necessary to trigger landslides varies considerably with the intensity of the landsliding (DL and Sevent); whereas for long antecedent periods the magnitude is largely independent of the cumulative amount of rainfall, and the largest values of landslide intensity are always preceded by abundant rainfall. Further, the analysis of the rainfall trend suggests that the trigger of landslides in the study area is related to seasonal rainfall. Copyright © 2010 John Wiley & Sons, Ltd. [source] Temperature sensitivity and substrate quality in soil organic matter decomposition: results of an incubation study with three substratesGLOBAL CHANGE BIOLOGY, Issue 6 2010J. Å. MARTIN WETTERSTEDT Abstract Kinetic theory suggests that the temperature sensitivity of decomposition of soil organic matter should increase with increasing recalcitrance. This ,temperature,quality hypothesis' was tested in a laboratory experiment. Microcosms with wheat straw, spruce needle litter and mor humus were initially placed at 5, 15 and 25 °C until the same cumulative amount of CO2 had been respired. Thereafter, microcosms from each single temperature were moved to a final set of incubation temperatures of 5, 15 and 25 °C. Straw decomposed faster than needle litter at 25 and 15 °C, but slower than needle litter at 5 °C, and showed a higher temperature sensitivity (expressed as Q10) than needle litter at low temperatures. When moved to the same temperature, needle litter initially incubated at 5 and 15 °C had significantly higher respiration rates in the final incubation than litters initially placed at 25 °C. Mor humus placed at equal temperatures during the initial and final incubations had higher cumulative respiration during the final incubation than humus experiencing a shift in temperature, both up- and downwards. These results indicate that other factors than substrate quality are needed to fully explain the temperature dependence. In agreement with the hypothesis, Q10 was always higher for the temperature step between 5 and 15 °C than between 15 and 25 °C. Also in agreement with the temperature,quality hypothesis, Q10 significantly increased with increasing degree of decomposition in five out of the six constant temperature treatments with needle litter and mor humus. Q10s for substrates moved between temperatures tended to be higher than for substrates remaining at the initial temperature and an upward shift in temperature increased Q10 more than a downward shift. This study largely supports the temperature,quality hypothesis. However, other factors like acclimation and synthesis of recalcitrant compounds can modify the temperature response. [source] Hierachically Nanostructured Mesoporous Spheres of Calcium Silicate Hydrate: Surfactant-Free Sonochemical Synthesis and Drug-Delivery System with Ultrahigh Drug-Loading CapacityADVANCED MATERIALS, Issue 6 2010Jin Wu Ultrahigh drug-loading capacity and the linear relationship between the cumulative amount of released drug and the natural logarithm of release time were discovered for the hierachically nanostructured mesoporous spheres of calcium silicate hydrate (CSH) obtained by a surfactant-free sonochemical method (see figure). During the release of loaded ibuprofen in simulated body fluid, CSH gradually transformed to hydroxyapatite. [source] Prostate cancer and PSA among statin users in the Finnish prostate cancer screening trialINTERNATIONAL JOURNAL OF CANCER, Issue 7 2010Teemu J. Murtola Abstract Decreased risk of advanced prostate cancer has been reported among men using statins. However, the evidence on overall prostate cancer risk is conflicting. We compared the relative risk between current users and non-users of statins or other cholesterol-lowering medications in a population undergoing systematical prostate cancer screening. The study cohort comprised of 23,320 men participating in the screening arm of the Finnish prostate cancer screening trial during 1996,2004. Information on medication use was obtained from a comprehensive national prescription database. Cox proportional hazards regression was used to calculate multivariable adjusted hazard ratios (HRs) for prostate cancer. Serum prostate-specific antigen (PSA) level was compared between current users and non-users of cholesterol-lowering drugs. Compared with medication non-users, the overall prostate cancer incidence was decreased among statin users [HR 0.75, 95% confidence interval (CI) 0.63,0.89]. The inverse association was dose-dependent with cumulative amount of statin use, and strongest for low-grade and early stage tumors. The incidence was nonsignificantly lower also among users of other types of cholesterol-lowering drugs (HR 0.62, 95% CI 0.28,1.38), but without dose-dependence. Age-adjusted median serum PSA tended to be lower among users of cholesterol-lowering drugs, but the relative risk decrease among statin users was not related to decreased PSA. Overall incidence of prostate cancer was lowered among statin users when bias due to differential PSA testing between medication users and non-users was eliminated by systematical prostate cancer screening. Cholesterol-lowering with statins seems beneficial for prostate cancer prevention. [source] Development of Gelatin Hydrogel Pads as Antibacterial Wound DressingsMACROMOLECULAR BIOSCIENCE, Issue 10 2009Vichayarat Rattanaruengsrikul Abstract Gelatin hydrogel pads have been prepared from a 10,wt.-% gelatin solution that contained 2.5,wt.-% AgNO3 in 70% v/v acetic acid by a solvent-casting technique. The AgNO3 -containing gelatin solution was aged under mechanical stirring for various time intervals to allow for the formation of silver nanoparticles (nAgs). The formation of nAgs was monitored by a UV-vis spectrophotometer. The morphology and size of the nAgs were characterized by transmission electron microscopy (TEM). To improve the water resistance of the hydrogels, various contents of glutaraldehyde (GTA) were added to the AgNO3 -containing gelatin solution to cross-link the obtained gelatin hydrogels. These hydrogels were tested for their water retention and weight loss behavior, release characteristics of the as-loaded silver, and antibacterial activity against Gram-negative Escherichiacoli and Gram-positive Staphylococcusaureus. The AgNO3 -containing gelatin solution that had been aged for 5 d showed the greatest number of nAgs formed. The size of these particles, based on TEM results, was 10,11,nm. With an increase in the GTA content used to cross-link the hydrogels, the water retention, the weight loss, and the cumulative amount of silver released were found to decrease. Finally, all of the nAg-loaded gelatin hydrogels could inhibit the growth of the tested pathogens, which confirmed their applicability as antibacterial wound dressings. [source] Discrete search allocation game with false contactsNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 1 2007Ryusuke Hohzaki Abstract This paper deals with a two-person zero-sum game called a search allocation game, where a searcher and a target participate, taking account of false contacts. The searcher distributes his search effort in a search space in order to detect the target. On the other hand, the target moves to avoid the searcher. As a payoff of the game, we take the cumulative amount of search effort weighted by the target distribution, which can be derived as an approximation of the detection probability of the target. The searcher's strategy is a plan of distributing search effort and the target's is a movement represented by a path or transition probability across the search space. In the search, there are false contacts caused by environmental noises, signal processing noises, or real objects resembling true targets. If they happen, the searcher must take some time for their investigation, which interrupts the search for a while. There have been few researches dealing with search games with false contacts. In this paper, we formulate the game into a mathematical programming problem to obtain its equilibrium point. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007 [source] Relative lung and systemic bioavailability of sodium cromoglycate inhaled products using urinary drug excretion post inhalationBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 4 2002Osama Aswania Abstract The relative lung and systemic bioavailability of sodium cromoglycate following inhalation by different methods have been determined using a urinary excretion pharmacokinetic method. On three separate randomised study days, 7 days apart, subjects inhaled (i) 4×5 mg from an Intal® metered dose inhaler (MDI), (ii) 4×5 mg from an MDI attached to a large volume spacer (MDI+SP) and (iii) 20 mg from an Intal Spinhaler® (DPI). Urine samples were provided at 0, 0.5, 1, 2, 5 and 24 h post dose. The mean (S.D.) amount of sodium cromoglycate excreted in the urine during the first 30 min post inhalation was 38.1 (27.5), 222.3 (120.3) and 133.1 (92.2) ,g following MDI, MDI+SP and DPI, respectively. The mean ratio (90% confidence interval) of these amounts excreted in the urine over the first 30 min for MDI+SP vs MDI, DPI vs MDI and MDI+SP vs DPI was 801.0 (358.0, 1244; p<0.002)%, 457.0 (244.0, 670.0; p<0.02)% and 262.4 (110.2, 414.5)%, respectively. Similarly for the 24 h cumulative amount of sodium cromoglycate excreted over the 24 h post inhalation the ratios were 375.4 (232.9, 517.9; p<0.005)%, 287.5 (183.4, 391.6; p<0.02)% and 211.4 (88.3, 334.5)%, respectively. The results highlight better lung deposition of sodium cromoglycate from a metered dose inhaler attached to a large volume spacer. Copyright © 2002 John Wiley & Sons, Ltd. [source] | |||||||||||||