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Sharp Increase (sharp + increase)
Selected AbstractsProfessional Errors Caused by Lasers and Intense Pulsed Light Technology in Dermatology and Aesthetic Medicine: Preventive Strategies and Case StudiesDERMATOLOGIC SURGERY, Issue 2 2002Baerbel Greve MD background. The use of lasers and intense pulsed light (IPL) technology has become established practice in dermatology and aesthetic medicine. The increase in popularity and widespread use of such equipment has been accompanied by a sharp increase in the number of case reports about professional errors. objective. We present 14 case studies of professional errors. methods. Selected representative case reports are used to illustrate and discuss typical professional errors and serve as the basis for creating preventive strategies. results. Recommendations have been developed for the following areas: physician training, patient information, documentation, diagnosis, indication, test treatment, and performing treatment. conclusion. The use of lasers and IPL technology in dermatology and aesthetic medicine requires practitioners not only to have high levels of training and experience, but also to exercise professional judgment. In spite of all of the precautions taken, the risk of complications and side effects can be reduced but not completely eliminated. [source] Heroin users in Australia: population trendsDRUG AND ALCOHOL REVIEW, Issue 1 2004C. YALÇIN KAYA Senior Lecturer Abstract The aim of this paper is to identify certain important population trends among heroin users in Australia for the period 1971 , 97, such as: population growth, initiation, i.e. the number who were initiated to heroin in a given year, and quitting, i.e. the number that quit using heroin. For this purpose, we summarize and extract relevant characteristics from data from National Drug Strategy Household Survey (NDSHS 1998) conducted in Australia in 1998. We devise a systematic procedure to estimate historical trends from questions concerning past events. It is observed from our findings that the size of the heroin user population in Australia is in a sharp increase, especially from the early 1980s onwards. The general trend obtained for the period 1971 , 97 is strikingly similar to that obtained by Hall et al. (2000) for the dependent heroin user population in Australia, even though their study was based on different datasets and a different methodology. In our reconstruction of the time history we also detect a levelling-off prior to 1990. Initiation is also observed to be on a sharp increase. The latter trend is accompanied by a similar trend of quitting, perhaps indicating a relatively short heroin use career. A sharp decrease in both initiation and quitting is observed after 1990. In conclusion, in the case of the trend in the population of heroin users a high rate of growth has been identified that is consistent with the existing literature. In the process, we demonstrated that even a static survey such as NDSHS 1998 can, sometimes, be used to extract historical (dynamic) trends of certain important variables. [source] Discussion of landslide self-organized criticality and the initiation of debris flowEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2007Chen Chien-Yuan Abstract The study contains descriptions of landslides and debris flows in a small upland catchment in Taiwan between 1986 and 2004. This catchment, the Chushui Creek, is situated near the epicentre of the 1999 M7·6 Chi-Chi earthquake. This is an area with high background erosion rate. The Chi-Chi earthquake caused a sharp increase in the rate of mass wasting in the epicentral area, and the data presented in this study illustrates the geomorphic change associated with the earthquake. The measurements of the geometry of the trunk stream of the Chushui catchment also show its change due to the impact of a strong typhoon in 1996. Two channel reaches that were affected by separate debris flows during this event were identified. Each reach has three sections: scour, transfer and deposition. Cross profiles of these sections show a systematic change from V-shaped bedrock channel in the scour areas to flat-floored channel in the transfer and deposition areas. Debris flows also occurred on other occasions in this channel, and their frequency has increased since the 1999 earthquake. In addition, this study contains precise geographic and statistical descriptions of the landslides triggered by three typhoons and an earthquake that affected the catchment since 1996. The total landslide area is measured for different time intervals, and a marked increase in landslide incidence is found after the 1999 earthquake. Frequency,area plots of the 126 landslides in the catchment indicate a power-law scaling with an exponent of about -1·5 of these quantities, as has been observed in other studies. We propose that a link exists between landslide frequency,area distributions and initialization of debris flow in the catchment. It may be classified as a self-organized criticality process with a critical frequency,area distribution for the landslide population. In this case, the landslide frequency,area distribution is useful in quantifying the severity of the trigger and the contribution of landslides to debris flow. Copyright © 2006 John Wiley & Sons, Ltd. [source] Schumpeterian Growth Theory and the Dynamics of Income InequalityECONOMETRICA, Issue 3 2002Philippe Aghion In this lecture, it is argued that Schumpeterian Growth Theory, in which growth is driven by a sequence of quality-improving innovations, can shed light on two important puzzles raised by the recent evolution of wage inequality in developed economies. The first puzzle concerns wage inequality between educational groups, which has substantially risen in the US and the UK during the past two decades following a sharp increase in the supply of educated labor. The second puzzle concerns wage inequality within educational groups, which accounts for a large fraction of the observed increase in wage inequality, although in contrast to between-group wage inequality it has mainly affected the temporary component of income. [source] Juvenile Hormone Binding Protein Titers During Adult Metamorphosis in Manduca sextaENTOMOLOGICAL RESEARCH, Issue 4 2003Young Jin KANG ABSTRACT ABSTRACT During the pupal and adult stages, the JHBP levels displayed a sex-related difference, with females showing higher levels than males. A sharp increase in JHBP levels was observed at day 2 of the pupal stage. After day 2 the JHBP titer declined precipitously, and then remained unchanged until day 12 in males. JHBP titers in females decreased slightly after day 2 and then remained relatively constant until day 12. In both sexes, the JHBP levels showed a steep increase and peaked around day 15. During the previtellogenic period, the JHBP titers declined dramatically until adult ecdysis. During early adult stage, JHBP titiers in the female remained constant at preecdysis level. This information could broaden our understanding of pest physiology during adult metamorphosis, and could have extensive implications for developing insect growth regulators to control agricultural pests. [source] Transcription dynamics of the functional tfdA gene during MCPA herbicide degradation by Cupriavidus necator AEO106 (pRO101) in agricultural soilENVIRONMENTAL MICROBIOLOGY, Issue 3 2008Mette Haubjerg Nicolaisen Summary A modified protocol for simultaneous extraction of RNA and DNA, followed by real-time polymerase chain reaction quantification, was used to investigate tfdA gene expression during in situ degradation of the herbicide MCPA (4-chloro-2-methylphenoxy-acetic acid) in soil. tfdA encodes an ,-ketoglutarate-dependent dioxygenase catalysing the first step in the degradation pathway of MCPA and 2,4-D (2,4-dichlorophenoxy-acetic acid). A linear recovery of tfdA mRNA over three orders of magnitude was shown, and the tfdA mRNA level was normalized using the tfdA mRNA/DNA ratio. The density of active cells required for tfdA mRNA detection was 105 cells g,1 soil. Natural soil microcosms inoculated with Cupriavidus necator (formerly Ralstonia eutropha) AEO106 (pRO101) cells were amended with four different MCPA concentrations (2, 20, 50 and 150 mg kg,1). Mineralization rates were estimated by quantification of 14CO2 emission from degradation of 14C-MCPA. tfdA mRNA was detected 1 h after amendment at all four concentrations. In soils amended with 2 and 20 mg kg,1, the mRNA/DNA ratio for tfdA demonstrated a sharp transient maximum of tfdA expression from no to full expression within 3 and 6 h respectively, followed by a decline and complete loss of expression after 19 and 43 h. A more complex pattern of tfdA expression was observed for the higher 50 and 150 mg kg,1 amendments; this coincided with growth of C. necator AEO106 (pRO101) in the system. Repeated amendment with MCPA after 2 weeks in the 20 mg kg,1 scenario revealed a sharp increase of tfdA mRNA, and absence of a mineralization lag phase. For all amendments, tfdA mRNA was detectable only during active mineralization, and thus revealed a direct correlation between tfdA mRNA presence and microbial degrader activity. The present study demonstrates that direct analysis of functional gene expression dynamics by quantification of mRNA can indeed be made in natural soil. [source] Use of monoclonal antibodies to quantify the dynamics of ,-galactosidase and endo-1,4-,-glucanase production by Trichoderma hamatum during saprotrophic growth and sporulation in peatENVIRONMENTAL MICROBIOLOGY, Issue 5 2005Christopher R. Thornton Summary Trichoderma species are ubiquitous soil and peat-borne saprotrophs that have received enormous scientific interest as biocontrol agents of plant diseases caused by destructive root pathogens. Mechanisms of biocontrol such as antibiosis and hyperparasitism are well documented and the biochemistry and molecular genetics of these processes defined. An aspect of biocontrol that has received little attention is the ability of Trichoderma species to compete for nutrients in their natural environments. Trichoderma species are efficient producers of polysaccharide-degrading enzymes that enable them to colonize organic matter thereby preventing the saprotrophic spread of plant pathogens. This study details the use of monoclonal antibodies (mAbs) to quantify the production of two enzymes implicated in the saprotrophic growth of Trichoderma species in peat. Using mAbs specific to the hemicellulase enzyme ,-galactosidase (AGL) and the cellulase enzyme endo-1,4-,-glucanase (EG), the relationship between the saprotrophic growth dynamics of a biocontrol strain of Trichoderma hamatum and the concomitant production of these enzymes in peat-based microcosms was studied. Enzyme activity assays and enzyme protein concentrations derived by enzyme-linked immunosorbent assay (ELISA) established the precision and sensitivity of mAb-based assays in quantifying enzyme production during active growth of the fungus. Trends in enzyme activities and protein concentrations were similar for both enzymes, during a 21-day sampling period in which active growth and sporulation of the fungus in peat was quantified using an independent mAb-based assay. There was a sharp increase in active biomass of T. hamatum 3 days after inoculation of microcosms with phialoconidia. After 3 days there was a rapid decline in active biomass which coincided with sporulation of the fungus. A similar trend was witnessed with EG activities and concentrations. This showed that EG production related directly to active growth of the fungus. The trend was not found, however, with AGL. There was a rapid increase in enzyme activities and protein concentrations on day 3, after which they remained static. The reason for the maintenance of elevated AGL probably resulted from secretion of the enzyme from conidia and chlamydospores. ELISA, immunofluoresence and immunogold electron microscopy studies of these cells showed that the enzyme is localized within the cytoplasm and is secreted extracellularly into the surrounding environment. It is postulated that release of oligosaccharides from polymeric hemicellulose by the constitutive spore-bound enzyme leads to AGL induction and could act as an environmental cue for spore germination. [source] Transcript and activity levels of different Pleurotus ostreatus peroxidases are differentially affected by Mn2+ENVIRONMENTAL MICROBIOLOGY, Issue 5 2001Roni Cohen The white-rot fungus Pleurotus ostreatus produces both manganese-dependent peroxidase (MnP) and versatile peroxidase (VP) in non-manganese-amended peptone medium (PM). We studied the effect of Mn2+ supplementation on MnPs and VPs in P. ostreatus by analysing the enzymatic and transcript abundance profiles of the peroxidases, as well as the lignin mineralization rate. The fungus was grown in PM under solid-state conditions using perlite as an inert solid support. Mn2+ amendment resulted in a 1.7-fold increase in [14C]-lignin mineralization relative to unamended medium. Anion-exchange chromatography was used to resolve the fungal peroxidase's enzymatic activity profile. Five peaks (P1,P5) of VP and one peak (P6) of MnP activity were detected in unamended medium. In Mn2+ -amended medium, a reduction in the activity of the VPs was observed. On the other hand, a sharp increase in the MnP activity level of peak P6 was detected. The P6 isoenzyme was purified and showed manganese-dependent peroxidation of phenolic substrates. Internal sequence analysis of the purified enzyme revealed 100% identity with the deduced amino acid sequence of P. ostreatus MnP3 (GenBank AB016519). The effect of Mn2+ on the relative abundance of gene transcripts of three VPs and one MnP from P. ostreatus was monitored using reverse transcription,polymerase chain reaction (RT,PCR) with oligonucleotide primer sets synthesized on the basis of non-conserved sequences of the different peroxidases. The reduction in VP gene transcript abundance and the increase in mnp3 transcript level were collinear with the changes observed in the enzyme activity profiles. These results indicate that the activity of peroxidases is regulated at the transcriptional level. We suggest that the expression of MnP and VP may be differentially regulated by the presence of Mn2+. [source] Oral health-related quality of life and its relationship with health locus of control among Indian dental university studentsEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2008S. Acharya Abstract Objectives:, The objectives of this study were to assess the relationship between Oral Health-Related Quality of Life (OHRQoL) and Health Locus of Control (HLC) among students in an Indian dental school. Materials and methods:, A cross sectional study design was used. Three hundred and twenty-five dental students returned completed forms containing the 14 item Oral Health Impact Profile (OHIP-14) and the 18 item Multidimensional Health Locus of Control Scale (MHLC). Results:, The results showed that the perceived OHRQoL differed among students studying in different stages of the dental course. The OHRQoL dimensions of ,Social Handicap' and ,Handicap' were significantly (P < 0.01) lower among the later years of the course than the freshman year students. There was a sharp increase in Self-reported dental problems, in particular, Malocclusion, Tooth decay, Calculus among the third year and final year students respectively. The OHIP-14 scores were significantly higher among those with self-reported oral problems. Correlation analysis between the OHIP-14 and the MHLC scores also showed a statistically significant (P < 0.01) correlation between the ,Chance' dimension of the MHLC and OHIP-14 scores. Conclusions:, The results of this study underscored the relationship between the OHRQoL and HLC and of importance of assessing health attitudes and their impact on OHRQoL among the dental student community. [source] Electrolytic Deposition of Hydroxyapatite Coating on CoNiCrMo SubstratesADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Dong-Yang Lin Hydroxyapatite (HA) coating was fabricated on CoNiCrMo alloy by electrolytic deposition (ELD). Different kinds of uncharged substrates were placed close to the cathode separately during the ELD process. Both CoNiCrMo and uncharged substrates were covered with uniform HA coatings composed of hexagonal prism crystals after 60,min deposition. The pH value of the bulk solution changed hardly while the local pH had a sharp increase after ELD. The results demonstrate the local pH plays a crucial role in the ELD process. [source] Increased bacterial load in shrimp hemolymph in the absence of prophenoloxidaseFEBS JOURNAL, Issue 18 2009Fernand F. Fagutao Invertebrates rely on their innate immune responses to protect themselves from pathogens, one of which is melanization of bacteria mediated by the activation of phenoloxidase (PO). Furthermore, invertebrate hemolymph, even that of healthy individuals, has been shown to contain bacterial species. The mechanisms that prevent these bacteria from proliferating and becoming deleterious to the host are, however, poorly understood. Here, we show that knocking down the activity of the inactive precursor of PO [prophenoloxidase (proPO)] by RNA interference resulted in a significant increase in the bacterial load of kuruma shrimp, Marsupenaeus japonicus, even in the absence of a bacterial or viral challenge. Silencing of proPO also led to a sharp increase in shrimp mortality. In addition, the hemolymph of proPO-depleted shrimp had significantly lower hemocyte counts and PO activity than control samples. Microarray analysis after proPO silencing also showed a decrease in the expression of a few antimicrobial peptides, but no effect on the expression of the genes involved in the clotting system. Treatment with antibiotics prior to and after proPO dsRNA injection, to counteract the loss of proPO, resulted in a significant increase in shrimp survival. Our results therefore show that the absence of proPO renders the shrimp incapable of controlling bacteria present in the hemolymph, and that proPO is therefore essential for its survival. [source] ,-diversity fluctuations in Early,Mid Ordovician brachiopod communities of South ChinaGEOLOGICAL JOURNAL, Issue 3-4 2006R.-B. Zhan Abstract Lower to Middle Ordovician transitional strata (Acrograptus filiformis Biozone to Exigraptus clavus Biozone) of the Upper Yangtze Platform contain rich and diverse brachiopods, particularly in the Daguanshan Formation of Sichuan Province, the Meitan Formation of Guizhou Province, and the Yingpan Formation of Houping, Chongqing City. On the basis of multivariate analyses of 207 samples (about 15,000 brachiopod specimens) and 61 species from these strata, 23 brachiopod-dominated communities and associations are delineated through six graptolitic biozones (Acrograptus filiformis to Exigraptus clavus biozones). The disparity of brachiopod associations or ,-diversity, as measured by the number of contemporaneous associations across variable ecological settings, was low in the A. filiformis Biozone and increased through the overlying graptolitic biozones to reach an acme in the Azygograptus suecisus and Expansograptus hirundo biozones, where as many as nine different brachiopod associations thrived in mid-shelf and also established in inner- and outer-shelf environments. Despite a sharp increase in ,-diversity within the Didymograptellus eobifidus Biozone, ,-diversity remained relatively low, with only three distinct brachiopod communities. The diversity of brachiopod associations suffered an abrupt drop in the E. clavus Biozone, as a result of a major faunal turnover event, with only a single Metorthis Community present in an upper mid-shelf setting. Temporally, brachiopod associations appear to be most stable in mid-shelf settings, with the Paralenorthis, Sinorthis, Desmorthis, and Euorthisina communities having a relatively high ,-diversity and lasting through two to five graptolitic biozones. In both species composition and temporal duration, the brachiopod associations at the shallow- (BA1 to upper BA2) and deep-shelf (BA4) settings are unstable, characterized by low ,-diversity and rapid vertical changes. This study implies that, during the Early and Mid Ordovician, brachiopod communities already attained a high level of organization in mid-shelf settings, but remained poorly established in high-stress environments of very shallow or very deep shelf settings. Copyright © 2006 John Wiley & Sons, Ltd. [source] Swarms of microearthquakes associated with the 2005 Vulcanian explosion sequence at Volcán de Colima, MéxicoGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2010Vyacheslav M. Zobin SUMMARY The swarms of microearthquakes, that appeared at Volcán de Colima, México before and after its large 2005 Vulcanian explosions, are discussed. The study of 966 microearthquakes is based on the seismic records of short-period seismic station EZV4 situated at a distance of 1.7 km from the crater. Three samples of microearthquakes were selected: the seismic records associated with a single 2005 September 16 large explosion, and the seismic records associated with two sequences of large explosions, the 2005 March 10 and 13 explosions and the 2005 May 30 and June 2, 5 and 7 explosions. These explosions were seven of 15 large explosions (E, 1011 J) that occurred during the 2005 explosive sequence. The microearthquake waveforms were identified as the records of rockfalls and microexplosions. The explosive microearthquakes represent from 84 to 89 per cent of the total number of microearthquakes with the readable waveforms. The dominant frequencies of the explosive microearthquakes were 2.8 Hz for the 2005 March explosion sequence and 2005 September 16 explosion, and 1.3, 2.0 and 2.8 Hz for the 2005 May-June explosion sequence. Energy of microexplosions that generated the microearthquake waveforms ranged from 104 to 7 × 107 J. The force component, corresponding to the largest microexplosive events, was estimated at a level from 3.1 × 107 to 3.6 × 108 N. The appearance of microearthquakes before large volcanic explosions and the sharp increase in their rate of appearance some hours before an explosion makes them a useful instrument for volcano monitoring. [source] Reform in a Cold Climate: Change in US Campaign Finance LawGOVERNMENT AND OPPOSITION, Issue 4 2005Dean McSweeney The Bipartisan Campaign Reform Act (BCRA) of 2002 was the first major change in US federal campaign finance law in a quarter of a century. Many attempts at reform had failed in that period. Few members of Congress were enthusiasts for reform, the two parties and two chambers had conflicting interests to protect, successive presidents did not promote the issue and public pressure for reform was weak. When reform was achieved in 2002, many of these formidable obstacles remained in place. This paper draws on the literature of public interest reform and policy innovation to attribute the change to a policy entrepreneur whose resources had undergone a sharp increase, the neutralization of opposition, the impact of an event (the bankruptcy of the Enron Corporation) and membership turnover in Congress. The substantial support for the bill in Congress from Democrats, the party with most to lose from reform, is attributed to the inescapability of past commitments. [source] Fractures and avascular necrosis before and after orthotopic liver transplantation: Long-term follow-up and predictive factors,HEPATOLOGY, Issue 4 2007Maureen M. J. Guichelaar With early posttransplant bone loss, orthotopic liver transplantation (OLT) recipients experience a high rate of fracturing and some avascular necrosis (AVN), but little is known about the incidence of and predictive factors for these skeletal complications. We studied 360 consecutive patients who underwent transplantation for primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) and assessed both vertebral and nonvertebral (rib, pelvic, and femur) fractures in a protocolized fashion. Before OLT, 20% of the patients had experienced fracturing, and 1.4% of the patients had experienced AVN. Following OLT, there was a sharp increase in fracturing, with a 30% cumulative incidence of fractures at 1 year and 46% at 8 years after transplantation. In contrast to previous studies, there was a similar incidence of posttransplant vertebral and nonvertebral fractures. The greatest risk factors for posttransplant fracturing were pretransplant fracturing and the severity of osteopenia and posttransplant glucocorticoids. Nine percent of the liver recipients experienced AVN after OLT, and this correlated with pretransplant and posttransplant lipid metabolism, bone disease (bone mineral density and fracturing), and posttransplant glucocorticoids. A novel association between cholestasis and AVN was also identified, the mechanism for which is not known. Conclusion: Fortunately, recent years have seen an increase in the bone mass of liver recipients and, along with this, less fracturing and less AVN. Nonetheless, 25% of patients undergoing OLT for chronic cholestatic liver disease still develop de novo fractures after OLT; this situation demands an ongoing search for effective therapeutic agents for these patients. (HEPATOLOGY 2007.) [source] Impact of land use on the hydraulic properties of the topsoil in a small French catchmentHYDROLOGICAL PROCESSES, Issue 17 2010E. Gonzalez-Sosa Abstract The hydraulic properties of the topsoil control the partition of rainfall into infiltration and runoff at the soil surface. They must be characterized for distributed hydrological modelling. This study presents the results of a field campaign documenting topsoil hydraulic properties in a small French suburban catchment (7 km2) located near Lyon, France. Two types of infiltration tests were performed: single ring infiltration tests under positive head and tension-disk infiltration using a mini-disk. Both categories were processed using the BEST,Beerkan Estimation of Soil Transfer parameters,method to derive parameters describing the retention and hydraulic conductivity curves. Dry bulk density and particle size data were also sampled. Almost all the topsoils were found to belong to the sandy loam soil class. No significant differences in hydraulic properties were found in terms of pedologic units, but the results showed a high impact of land use on these properties. The lowest dry bulk density values were obtained in forested soils with the highest organic matter content. Permanent pasture soils showed intermediate values, whereas the highest values were encountered in cultivated lands. For saturated hydraulic conductivity, the highest values were found in broad-leaved forests and small woods. The complementary use of tension-disk and positive head infiltration tests highlighted a sharp increase of hydraulic conductivity between near saturation and saturated conditions, attributed to macroporosity effect. The ratio of median saturated hydraulic conductivity to median hydraulic conductivity at a pressure of , 20 mm of water was about 50. The study suggests that soil texture, such as used in most pedo-transfer functions, might not be sufficient to properly map the variability of soil hydraulic properties. Land use information should be considered in the parameterizations of topsoil within hydrological models to better represent in situ conditions, as illustrated in the paper. Copyright © 2010 John Wiley & Sons, Ltd. [source] Incidence rates of hepatocellular carcinoma in the U.S. and Denmark: Recent trendsINTERNATIONAL JOURNAL OF CANCER, Issue 7 2007Peter Jepsen Abstract Hepatocellular carcinoma (HCC) incidence rates vary by gender, age, time and place. Geographic differences in gender-, age- and time-specific HCC incidence rates may improve the understanding of HCC risk factors. We computed annual standardized HCC incidence rates for the United States (U.S.) 1978,2004 and for Denmark 1978,2003. Among U.S. white men aged 45,59 the HCC incidence rates were comparable to the Danish rates until 1995, but more than tripled over the following 8 years to become over 2.5-fold higher than the Danish rate by 2003, with an additional small increase in 2004. HCC rates in black U.S. men aged 45,59 also increased sharply after 1995. Among women aged 45,59 the U.S. HCC rates were elevated in recent years, but did not show the sharp increase after 1995 observed among men; the Danish rates showed a decreasing trend throughout 1978,2003. U.S. rates in the 60,74 years age groups showed a protracted and gradual increase with no evidence of a sharp increase after 1995. In the 60,74 years age group, rates for Danish men were comparable to those for U.S. white men, but rates for Danish women decreased. The U.S. prevalence rates of hepatitis C virus (HCV) infection are 2.1 and 1.1% for men and women, respectively, the Danish 0.2%. The disparity in HCV prevalence is the most likely explanation for the differences between Danish and U.S. trends in HCC incidence. Intravenous drug use and blood transfusions are the major sources of HCV, and we suggest that increased HCV infection prevalence among Vietnam era military veterans may contribute to the earlier and steeper HCC incidence increase for U.S. men than for U.S. women. © 2007 Wiley-Liss, Inc. [source] Variability of extreme temperature events in south,central Europe during the 20th century and its relationship with large-scale circulationINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2003Peter Domonkos Abstract The variability of winter extreme low-temperature events and summer extreme high-temperature events was investigated using daily temperature series (1901,98) from 11 sites in central and southern Europe. An extreme temperature event (EXTE) is defined by various threshold values of daily temperature or daily temperature anomaly. Systematic changes in the frequencies of EXTEs are investigated by the Mann,Kendall test and a method based on the Wilcoxon test. The catalogue of macrocirculation types over central Europe (the Hess,Brezowsky classification) is applied to investigate the connections between EXTEs and large-scale circulation. Circulation classes (HBC) are defined, and mostly spatial averages of EXTEs are examined. There were large long-term fluctuations in the frequencies of both winter extreme cold events (EXCEs) and summer extreme warm events (EXWEs) during the 20th century. The systematic changes referring to the entire period indicate a slight warming tendency, but only a few of the changes, mostly in the northernmost sites, are statistically significant. Strong connections are present between the frequencies of EXTEs and the large-scale circulation on various time scales, particularly for EXCEs. The spatial differences of EXTE fluctuations and EXTE,HBC connections are small within the study area. Northerlies and easterlies, as well as meridional and anticyclonic situations, are favourable for EXCEs, whereas southerlies and persistent anticyclonic situations are favourable for EXWE occurrences. In the latest decades, a decline in the frequency of EXCEs and a sharp increase in the frequency of EXWEs happened, and the residence times of the circulation patterns over central Europe became longer both in winter and summer. Copyright © 2003 Royal Meteorological Society [source] The establishment of an urban bird populationJOURNAL OF ANIMAL ECOLOGY, Issue 5 2008Christian Rutz Summary 1Despite the accelerating global spread of urbanized habitats and its associated implications for wildlife and humans, surprisingly little is known about the biology of urban ecosystems. 2Using data from a 60-year study period, this paper provides a detailed description of how the northern goshawk Accipiter gentilis L. , generally considered a shy forest species , colonized the city of Hamburg, Germany. Six non-mutually exclusive hypotheses are investigated regarding the environmental factors that may have triggered this invasion. 3The spatio-temporal analysis of 2556 goshawk chance observations (extracted from a total data set of 1 174 493 bird observations; 1946,2003) showed that hawks regularly visited the city centre decades before the first successful breeding attempts were recorded. Many observations were made in parts of the city where territories were established in later years, demonstrating that these early visitors had encountered, but not used, potential nest sites. 4Pioneer settlement coincided with: (i) an increase in (legal) hunting pressure on goshawks in nearby rural areas; (ii) an increase in avian prey abundance in the city; and (iii) a succession of severe winters in the Greater Hamburg area. On the other hand, there was no evidence to suggest that the early stages of the invasion were due to: (i) decreasing food availability in rural areas; (ii) major habitat changes in the city; or (iii) rural intraguild dynamics forcing hawks into urban refugia. While breeding numbers of a potential rural source population were at a long-term low when the city was colonized, prior to first settlement there was a sharp increase of goshawk chance observations in the city and its rural periphery. 5The urban population expanded rapidly, and pair numbers began to stabilize after about 10 years. Ringing data (219 ringed nestlings from 70 urban broods; 1996,2000) demonstrated that most urban recruits had fledged in the city, but also confirmed considerable gene flow between urban and rural habitats. Analysis of chance observations (as raw data or as detrended time series) suggested a tight coupling of population dynamics inside and outside the city. 6City-colonizations such as the one described here provide a valuable opportunity to study some fundamental aspects of population ecology on a scale at which detailed monitoring is logistically feasible. Furthermore, a good understanding of urban ecology has become essential for efficient wildlife conservation in modern, human-altered environments. [source] Influence of processing conditions on the weld line in doubly injection-molded glassy polycarbonate and polystyrene: Microindentation hardness studyADVANCES IN POLYMER TECHNOLOGY, Issue 1 2005M. Boyanova Abstract The microhardness (H) technique has been used to characterize the quality of the weld line in injection-molded tensile bars from a two-component machine in which both melt streams from the same material can be independently controlled. More specific, the influence of melt temperature and indentation location (closer or further from the sample edge parallel to the injection direction and across the weld line) has been followed on polycarbonate (PC) and polystyrene (PS) glassy samples. For both polymers at lower melt temperatures, a strong H decrease (between 15 and 50%) followed by a sharp increase in a narrow distance (around 0.10 mm), is observed. When the melt temperature increases up to 300°C (for PC) and 270°C (for PS), a much smaller H decrease is observed in the central part of the samples. However, closer to the tensile bar edges (2 mm) the weld line remains undetectable by microhardness measurements. The present results reveal that the processing temperature affects the broadening of the weld line through the conditions for effective mutual interdiffusion of chains from the two fronts coming from opposite sides. © 2005 Wiley Periodicals, Inc. Adv Polym Techn 24:14,20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20028 [source] Synthesis and simple method of estimating macroporosity of methyl methacrylate,divinylbenzene copolymer beadsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Muhammad Arif Malik Abstract Macroporous methyl methacrylate,divinylbenzene copolymer beads having diameter , 300 ,m were synthesized by free radical suspension copolymerization. The macroporosity was generated by diluting the monomers with inert organic liquid diluents. The macroporosity was varied in the range of ,0.1 to , 1.0 mL/g by varying a number of porosity controlling factors, such as the diluents, solvent to nonsolvent mixing ratios when employing a mixture of the two diluents, degree of dilution, and crosslinkage. Increase in pore volume from 0.1 to 0.45 mL/g resulted in a sharp increase in mesopores having diameters in the range of 3,20 nm whereas the macropores remained negligible when compared with mesopores. Increase in pore volume from 0.45 to 1 mL/g resulted in a sharp increase in macropores, whereas mesopores having diameters in the range of 3,20 nm remained almost constant. The mesopores having diameters in the range of 20,50 nm showed an increase with the increase in pore volume throughout the whole range of pore volume studied. Macroporosity characteristics, i.e., pore volume (Vm), surface area (SA), and pore size distributions were evaluated by mercury penetration method. Statistical analysis of the data obtained in the present study shows that the macroporosity characteristics can be estimated with a reasonable accuracy from the pore volumes, which in turn are determined from the densities of the copolymers. These results are explained on the basis of pore formation mechanism. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Application of chitosan solutions gelled by melB tyrosinase to water-resistant adhesivesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2008Kazunori Yamada Abstract An investigation was undertaken on the application of dilute chitosan solutions gelled by melB tyrosinase-catalyzed reaction with 3,4-dihydroxyphenethylamine (dopamine). The tyrosinase-catalyzed reaction with dopamine conferred water-resistant adhesive properties to the semi-dilute chitosan solutions. The viscosity of the chitosan solutions highly increased by the tyrosinase-catalyzed quinone conversion and the subsequent nonenzymatic reactions of o -quinones with amino groups of the chitosan chains. The viscosity of chitosan solutions highly increased in shorter reaction times by addition of melB tyrosinase. Therefore, in this study, the gelation of a chitosan solution was carried out without poly(ethylene glycol) (PEG), which was added for the gelation of chitosan solutions using mushroom tyrosinase. The highly viscous, gel-like modified chitosan materials were allowed to spread onto the surfaces of the glass slides, which were tightly lapped together and were held under water. Tensile shear adhesive strength of over 400 kPa was observed for the modified chitosan samples. An increase in either amino group concentration of the chitosan solutions or molecular mass of the chitosan samples used effectively led to an increase in adhesive strength of the glass slides. Adhesive strength obtained by chitosan materials gelled enzymatically was higher than that obtained by a chitosan gel prepared with glutaraldehyde as a chemical crosslinking agent. In addition, the use of melB tyrosinase led to a sharp increase in adhesive strength in shorter reaction times without other additives such as PEG. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Below-ground ectomycorrhizal community structure in a recently burned bishop pine forestJOURNAL OF ECOLOGY, Issue 6 2000P. Grogan Summary 1,The effects of wildfire ash on ectomycorrhizal (EM) associations were investigated by sampling bishop pine (Pinus muricata, D. Don) seedlings from control and ash-removed plots 1.5 years after a severe fire in a northern Californian P. muricata forest. The below-ground community composition of EM at the site was characterized using molecular techniques (PCR-RFLP and nucleotide sequencing). 2,A total of 30 fungal taxa were observed, many of which differed in their distribution between treatment and control seedlings. However, most of the taxa that were distinctive to either treatment or control seedlings occurred only once across the site, precluding statistical detection of potential ash effects on EM community composition. There were no significant effects of ash removal on plot-level mycorrhizal community richness or diversity, and there were no distinct treatment-related clusters in a principal components analysis. 3,Analysis of the combined data indicated that numbers of fungal taxa per seedling, numbers of successive root depth increments colonized by the same taxon, and distances to neighbouring seedlings colonized by the same taxon, were randomly distributed across the site for the majority of mycorrhizal fungi. These distributional patterns suggest that the post-fire mycorrhizal community structure on P. muricata arose primarily from successful colonization by randomly distributed point-source fungal inocula within the upper mineral soil layer of the forest floor. 4,By comparison with pre-fire studies from similar P. muricata sites nearby, our data indicate that severe wildfire disturbance resulted in marked changes in mycorrhizal community composition, and a sharp increase in the relative biomass of ascomycetous fungi. [source] US,Mexico fresh vegetable trade: the effects of trade liberalization and economic growthAGRICULTURAL ECONOMICS, Issue 1 2001Jaime E. Málaga NAFTA; Vegetables; Trade liberalization; Mexico Abstract Studies of US-Mexico vegetable trade have generally emphasized the importance of US tariffs in determining the competitive advantage of US producers. Even so, research has identified at least four factors related primarily to the different levels of economic development in the US and Mexico that also have important effects on US-Mexico agricultural trade in general and fresh vegetable trade in particular. These include the differential growth rates of US and Mexican real wages, production technology (yields), and per capita income as well as cyclical movements in the real Mexican Peso/US Dollar exchange rate. This study examines the relative contribution of NAFTA and the development-related factors to likely future changes in US fresh vegetable imports from Mexico. The analysis employs an econometric simulation model of US and Mexican markets for five fresh vegetables (tomatoes, cucumbers, squash, bell peppers, and onions) accounting for 80% of US fresh vegetable imports. The results suggest that the 1994,1995 Peso devaluation rather than NAFTA was primarily responsible for the sharp increase in US imports of Mexican vegetables observed in the first years following the implementation of NAFTA. Over time, however, the results suggest that differences in the growth rates of US and Mexican production yields and, to a lesser extent, of US and Mexican real incomes and/or real wage rates could plausibly contribute more to the future growth of US tomato, squash, and onion imports from Mexico than the trade liberalizing effects of NAFTA. [source] Effect of vaccination with recombinant modified vaccinia virus Ankara expressing structural and regulatory genes of SIVmacJ5 on the kinetics of SIV replication in cynomolgus monkeysJOURNAL OF MEDICAL PRIMATOLOGY, Issue 4 2001Donatella R.M. Negri The efficacy of a multicomponent vaccination with modified vaccinia Ankara constructs (rMVA) expressing structural and regulatory genes of simian immunodeficiency virus (SIVmac251/32H/J5) was investigated in cynomolgus monkeys, following challenge with a pathogenic SIV. Vaccination with rMVA-J5 performed at week 0, 12, and 24 induced a moderate proliferative response to whole SIV, a detectable humoral response to all but Nef SIV antigens, and failed to induce neutralizing antibodies. Two months after the last boost, the monkeys were challenged intravenously with 50 MID50 of SIVmac251. All control monkeys, previously inoculated with non-recombinant MVA, were infected by week two and seroconverted by weeks four to eight. In contrast a sharp increase of both humoral and proliferative responses at two weeks post-challenge was observed in vaccinated monkeys compared to control monkeys. Although all vaccinated monkeys were infected, vaccination with rMVA-J5 appeared to partially control viral replication during the acute and late phase of infection as judged by cell- and plasma-associated viral load. [source] External Constraints on Monetary Policy and the Financial AcceleratorJOURNAL OF MONEY, CREDIT AND BANKING, Issue 2-3 2007MARK GERTLER financial crises; exchange rate policy We develop a small open economy macroeconomic model where financial conditions influence aggregate behavior. Our goal is to explore the connection between the exchange rate regime and financial distress. We first show that a calibrated version of the model captures well the behavior of the Korean economy during its financial crisis period of 1997,98. In particular, the model accounts for the sharp increase in lending rates and the large drop in output, employment, investment, and measured productivity. The financial market frictions play an important role, further, explaining roughly half the decline in overall economic activity. We then perform some counterfactual exercises to illustrate how the fixed exchange rate regime likely exacerbated the crisis by tying the hands of monetary policy. [source] Periodontal therapy: a novel non-drug-induced experimental model to study human inflammationJOURNAL OF PERIODONTAL RESEARCH, Issue 5 2004F. D'Aiuto Background:, Chronic periodontitis causes a low-grade systemic inflammatory response; its standard treatment, however, induces an acute inflammatory response. The aim of this study was to describe the systemic inflammatory reactions to an intensive periodontal treatment regimen. Methods:, Fourteen otherwise healthy subjects suffering from severe chronic periodontitis were enrolled in a 1 month pilot single-blind trial. Intensive periodontal treatment, consisting of full-mouth subgingival root debridement delivered within a 6-h period, was performed. Periodontal parameters were recorded before and 1 month after completion of treatment. Blood samples were taken at baseline and 1, 3, 5, 7 and 30 days after treatment. Interleukin-1 receptor antagonist (IL-1Ra), Interleukin-6 (IL-6) and C-reactive protein (CRP) serum concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Complete blood counts were also performed. Results:, One day after treatment, mild neutrophilia and monocytosis (p < 0.05) and lymphopenia (p < 0.01) were accompanied by a sharp increase in inflammatory markers (IL-1Ra, IL-6, p < 0.01). A 10-fold increase in CRP (p < 0.001) was detected on day 1 and its kinetics followed a pattern of a classical acute phase response (significantly raised concentrations up to 1 week, p < 0.01). At 3,7 days after treatment, subjects presented also with a mild tendency towards a normocytic anaemic state (p < 0.01) and a degree of lympho-thrombocytosis (p < 0.05). The observed changes were similar to those expected following the well-characterized endotoxin-challenge model of inflammation. Conclusions:, Intensive periodontal treatment produced an acute systemic inflammatory response of 1 week duration and might represent an alternative to classic endotoxin-challenge or drug-induced models to study acute inflammation in humans. [source] WATER ABSORPTION EFFECTS ON BIAXIAL EXTENSIONAL VISCOSITY OF WHEAT FLOUR DOUGHJOURNAL OF TEXTURE STUDIES, Issue 2 2003FERNANDO OSORIO ABSTRACT Biaxial extensional viscosities of wheat flour dough at three water absorption levels were determined as a function of biaxial strain rates using lubricated squeezing flow. The shape of the curves obtained in this study showed a sharp increase followed by a gradual increase which could indicate the presence of viscoelastic effects, which is not the usual case reported in the published literature for other products when using this technique. Plasticizing effect of water coupled with the effect of the starch and the interaction among the other components of wheat flour dough could explain the rheological behavior of flour dough during lubricated squeezing flow testing. Values of biaxial extensional viscosities of wheat flour dough for the three water absorption levels obtained in this study showed significant differences in the entire deformation range (P < 0.05). [source] Strength Properties of Poled Lead Zirconate Titanate Subjected to Biaxial Flexural Loading in High Electric FieldJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2010Hong Wang The mechanical strength of poled lead zirconate titanate (PZT) has been studied using ball-on-ring (BoR) biaxial flexure tests with a high electric field applied concurrently. Both the as-received and the aged PZT specimens were tested. The Weibull plot and a 95% confidence ratio ring were used to characterize the responses of mechanical strength under various electric loading conditions. A fractographical study has been conducted at the same time, and the fracture origins or strength-limiting flaws of tested PZT specimens have been identified and characterized accordingly. The fracture toughness was further estimated to correlate with the obtained fracture stresses and flaws. It has been observed that electric field affects the mechanical strength of poled PZT, and the degree of the effect depends on the sign and magnitude of the applied electric field. Within the examined electric field range of ,3 to +3 times the coercive field, an increasing electric field resulted in a rapid strength decrease and a sharp increase with the turning point around the negative coercive field. Surface-located volume-distributed flaws were identified to be strength limiting for this PZT material. Variations of the mechanical strength with the electric field were believed to be related to the domain switching and amount of switchable domains. An aging effect on the mechanical strength of poled PZT could be significant, especially in the OC condition. These results and observations have the potential to serve probabilistic reliability analysis and design optimization of multilayer PZT piezo actuators. [source] Oxidative behaviour of fresh-cut ,Fuji' apples treated with stabilising substancesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2008Dr Christian Larrigaudière Abstract BACKGROUND:Although changes in the quality of fresh-cut products treated with chemical stabilisers have been extensively described in the literature, very little is known about the physiology of these products. This work aims to describe the physiological aspect and particularly the effects of chemical preservatives on the oxidative behaviour of fresh-cut apples. RESULTS:Immediately after treatment, the samples treated with the anti-browning agents (ascorbic acid + cysteine) exhibited a sharp increase in H2O2 levels (a five-fold increase when compared to the other samples) and peroxidative damage, especially at the beginning of the storage period (two-fold increase after 1 day). In line with this result, peroxidase (POX) activity decreased by 50% during the first day of storage, but no significant changes in superoxide dismutase (SOD) and catalase (CAT) activities were found between the different samples. H2O2 accumulation was not attributed to the action of cysteine but to a specific action of ascorbic acid, which mainly acted as a pro-oxidant under these conditions. CONCLUSION:The results presented in this work showed that ascorbic acid cause important oxidative damage in fresh-cut Fuji apples. Alternatives are required to prevent detrimental loss of quality resulting from this oxidative action. Copyright © 2008 Society of Chemical Industry [source] | |||||||||||||||||||||||||||||||||||||||||||