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121.
Pollen data have been recorded at Novi Sad in Serbia since 2000. The adopted method of producing pollen counts has been the use of five longitudinal transects that examine 19.64% of total sample surface. However, counting five transects is time consuming and so the main objective of this study is to investigate whether reducing the number to three or even two transects would have a significant effect on daily average and bi-hourly pollen concentrations, as well as the main characteristics of the pollen season and long-term trends. This study has shown that there is a loss of accuracy in daily average and bi-hourly pollen concentrations (an increase in % ERROR) as the sub-sampling area is reduced from five to three or two longitudinal transects. However, this loss of accuracy does not impact on the main characteristics of the season or long-term trends. As a result, this study can be used to justify changing the sub-sampling method used at Novi Sad from five to three longitudinal transects. The use of two longitudinal transects has been ruled out because, although quicker, the counts produced: (a) had the greatest amount of % ERROR, (b) altered the amount of influence of the independent variable on the dependent variable (the slope in regression analysis) and (c) the total sampled surface (7.86%) was less than the minimum requirement recommended by the European Aerobiology Society working group on Quality Control (at least 10% of total slide area).  相似文献   
122.
Environmental Science and Pollution Research - Mercury and selenium concentrations and Se:Hg molar ratio in edible muscle and hepatopancreas of the crab Callinectes arcuatus from coastal lagoons of...  相似文献   
123.
Levels of total suspended particles, PM10, PM2.5 and PM1 were continuously monitored at an urban kerbside in the Metropolitan area of Barcelona from June 1999 to June 2000. The results show that hourly levels of PM2.5 and PM1 are consistent with the daily cycle of gaseous pollutants emitted by traffic, whereas TSP and PM10 do not follow the same trend, at least in the diurnal period. The PM2.5/PM10 ratio is dependent on the traffic emissions, whereas additional contribution sources for the >10 μm fraction must be taken into account in the diurnal period. Different PM10 and PM2.5 source apportionment techniques were compared. A methodology based on the chemical determination of 83% of both PM10 and PM2.5 masses allowed us to quantify the marine (4% in PM10 and <1% in PM2.5), crustal (26% in PM10 and 8% in PM2.5) and anthropogenic (54% in PM10 and 73% in PM2.5) loads. Peaks of crustal contribution to PM10 (up to 44% of the PM10 mass) were recorded under Saharan air mass intrusions. A different seasonal trend was observed for levels of sulphate and nitrate, probably as a consequence of the different thermodynamic behaviour of these PM species and the higher summer oxidation rate of SO2.  相似文献   
124.

Background

The aim of this study was to describe the incidence of Congenital Diaphragmatic Hernia, CDH, associated with known or clinically suspected syndromes, and the postnatal outcomes from a large database for CDH.

Methods

Data from the multicenter, multinational database on infants with CDH (Congenital Diaphragmatic Hernia Study Group Registry) born from 1996 to 2020 were analyzed. Patients with known or suspected syndromes were grouped and outcome data were analyzed and compared to those without syndromic features.

Results

A total of 12,553 patients were entered in the registry during the study period, and 421 had reported known syndromes, representing 3.4% of all CDH cases in the registry. A total of 50 different associated syndromes were reported. In addition to those with clinically suspected genetic conditions, a total rate of genetic syndromes with CDH was 8.2%. The overall survival to discharge for syndromic CDH was 34% and for non-syndromic CDH was 76.7%. The most common were syndromes Fryns syndrome (19.7% of all syndromes, 17% survival), trisomy 18 or Edward syndrome (17.5%, 9% survival), trisomy 21 or Down syndrome (9%, 47% survival), trisomy 13 or Patau syndrome (6.7%, 14% survival), Cornelia de Lange syndrome (6.4% of all syndromes, 22% survival) and Pallister-Killian syndrome (5.5% of all syndromes, 39.1% survival). In addition, 379 cases had reported chromosomal anomalies and 233 cases had clinically suspected syndromes, based on two more dysmorphic features or malformations in addition to CDH, but without molecular diagnosis. The syndromic CDH group had lower birth weight and gestational age at birth and increased incidence of bilateral CDH (2.9%) and rates of non-repair (53%). The length of hospital stay was longer, and larger number of patients needed O2 at 30 days. Extracorporeal life support was used only in 15% of the cases. Those who underwent surgical repair had survival to discharge rates of 73%.

Conclusion

Syndromic CDH is rare and only 3.4% of the reported cases of CDH have a known syndrome or association, but, if including patients with two dysmorphic features malformations, in addition to CDH, altogether as many as 8.2% have a diagnosed or suspected genetic condition. These children have with lower survival rates. Given higher rates of non-repair and decreased extracorporeal life support use, along with a high early mortality, decision-making regarding goals of care clearly influences outcomes. Survival varies depending on the genetic cause. Early genetic diagnosis is important and may influence the decision-making.  相似文献   
125.
Arsenic contamination in groundwater is a severe global problem, most notably in Southeast Asia where millions suffer from acute and chronic arsenic poisoning. Removing arsenic from groundwater in impoverished rural or urban areas without electricity and with no manufacturing infrastructure remains a significant challenge. Magnetite nanocrystals have proven to be useful in arsenic remediation and could feasibly be synthesized by a thermal decomposition method that employs refluxing of FeOOH and oleic acid in 1-octadecene in a laboratory setup. To reduce the initial cost of production, $US 2600/kg, and make this nanomaterial widely available, we suggest that inexpensive and accessible “everyday” chemicals be used. Here we show that it is possible to create functional and high-quality nanocrystals using methods appropriate for manufacturing in diverse and minimal infrastructure, even those without electricity. We suggest that the transfer of this knowledge is best achieved using an open source concept.  相似文献   
126.
We study whether a government-sponsored voluntary pollution reduction program (VPR) promotes or deters the development of new environmental technologies that yield future emission reduction benefits. Using a panel of 127 U.S. manufacturing industries defined by 3-digit SIC classifications over the 1989–2004 period, we estimate impacts of industry-level participation in the 33/50 program, a VPR initiated by government regulators in 1991, on industry-level rates of environmental patenting. We find that higher rates of 33/50 program participation are associated with significant reductions in the number of successful environmental patent applications five to nine years after the program ended.  相似文献   
127.
Crepipatella dilatata (Calyptraeidae) is a common intertidal or shallow subtidal protandric hermaphroditic gastropod. Intertidal snails from Puerto Madryn, Chubut, Argentina (42°46′37″S, 64°54′51″ W), showed a high prevalence, up to 46?%, of a castrating larval microphallid trematode. Reproductive success was studied during a 2-year period from September 2007 to August 2009, and the results were compared to those from an unparasitized subtidal sample. Brooding females and males were never found infected. The proportion of brooding females was higher in months with a higher prevalence of infection. The number of brooding females in the intertidal sample was higher than in the subtidal sample. Generalized linear models were utilized to determine the effects of parasitism on the reproductive success of the host population. Anticipated reproduction in smaller females in the intertidal sample, increased reproductive success in months with higher prevalence, and unparasitized males are interpreted as fitness responses to ensure host population survival when the prevalence of trematode infection is high.  相似文献   
128.
129.
Geospatial indicators of emerging water stress: an application to Africa   总被引:3,自引:0,他引:3  
This study demonstrates the use of globally available Earth system science data sets for water assessment in otherwise information-poor regions of the world. Geospatial analysis at 8 km resolution shows that 64% of Africans rely on water resources that are limited and highly variable. Where available, river corridor flow is critical in augmenting local runoff, reducing impacts of climate variability, and improving access to freshwater. A significant fraction of cropland resides in Africa's driest regions, with 39% of the irrigation nonsustainable. Chronic overuse and water stress is high for 25% of the population with an additional 13% experiencing drought-related stress once each generation. Paradoxically, water stress for the vast majority of Africans typically remains low, reflecting poor water infrastructure and service, and low levels of use. Modest increases in water use could reduce constraints on economic development, pollution, and challenges to human health. Developing explicit geospatial indicators that link biogeophysical, socioeconomic, and engineering perspectives constitutes an important next step in global water assessment.  相似文献   
130.
Joostella strains are emerging candidates for biosurfactant production. Here such ability was analyzed for Joostella strain A8 in comparison with Alcanivorax strain A53 and Pseudomonas strain A6, all previously isolated from hydrocarbon enrichment cultures made of polychaete homogenates. In pure cultures Joostella sp. A8 showed the highest stable emulsion percentage(78.33%), hydrophobicity rate(62.67%), and an optimal surface tension reduction during growth in mineral medium supplemented with diesel oil(reduction of about 12 mN/m), thus proving to be highly competitive with Alcanivorax and Pseudomonas strains. During growth in pure culture different level of biodegradation were detected for Alcanivorax strain A53(52.7%),Pseudomonas strain A6(38.2%) and Joostella strain A8(26.8%). When growing in consortia,isolates achieved similar abundance values, with the best efficiency that was observed for the Joostella-Pseudomonas co-culture. Gas-chromatographic analysis revealed an increase in the biodegradation efficiency in co-cultures(about 90%), suggesting that the contemporary action of different bacterial species could improve the process. Results were useful to compare the efficiencies of well-known biosurfactant producers(i.e. Pseudomonas and Alcanivorax representatives) with a still unknown biosurfactant producer, i.e. Joostella, and to confirm them as optimal biosurfactant-producing candidates.  相似文献   
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