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11.
In the frame of the international SOILSAMP project, funded and coordinated by the National Environmental Protection Agency of Italy (APAT), uncertainties due to field soil sampling were assessed. Three different sampling devices were applied in an agricultural area using the same sampling protocol. Cr, Sc and Zn mass fractions in the collected soil samples were measured by k(0)-instrumental neutron activation analysis (k(0)-INAA). For each element-device combination the experimental variograms were calculated using geostatistical tools. The variogram parameters were used to estimate the standard uncertainty arising from sampling. The sampling component represents the dominant contribution of the measurement uncertainty with a sampling uncertainty to measurement uncertainty ratio ranging between 0.6 and 0.9. The approach based on the use of variogram parameters leads to uncertainty values of the sampling component in agreement with those estimated by replicate sampling approach.  相似文献   
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46,XY/47,XY, + 17p + mosaicism was found in two primary amniotic fluid cultures (AFCs). Fetal blood karyotype was normal, but ultrasonography revealed Dandy-Walker malformation and bilateral choroid plexus cysts. Following termination of pregnancy, fetal examination revealed post-axial polydactyly and neuroblastoma-in-situ affecting both adrenals in addition to the cerebellar abnormalities. Mosaicism for the aberrant cell line was confirmed in all fetal tissues sampled and in the placenta.  相似文献   
13.
The velvet belly Etmopterus spinax (Linnaeus, 1758) is a deep water bottom-dwelling species very common in the western Mediterranean sea. This species is a portion of the by-catch of the red shrimps and Norway lobsters otter trawl fisheries on the meso and ipo-bathyal grounds. A new, simple, rapid, and inexpensive vertebral preparation method was used on a total of 241 specimens, sampled throughout 2000. Post-cranial portions of vertebral column were removed and vertebrae were prepared for ageing readings. Band pair counts ranged from 0 to 9 in females, and from 0 to 7 in males. Von Bertalanffy growth equations estimated for both sexes suggested a higher longevity for females (males: L = 394.3 mm k = 0.19 t 0 = −1.41 L 0 = 92.7 mm A 99 = 18.24 years; females: L = 450 mm k = 0.16 t 0 = −1.09 L 0 = 72 mm A 99 = 21.66 years). Age estimations are discussed in the context of deep water shark species. This is the first successful attempt at delineating faint growth bands in the poorly calcified deep coned vertebrae of E. spinax. This technique may be used in other difficult poorly calcified species.  相似文献   
14.
Omphalopagus conjoined twins were diagnosed by ultrasonography in a pregnant woman at 21 weeks' gestation. In order to clarify the anatomical connections, magnetic resonance imaging (MRI) was performed, having achieved fetal paralysis by intravascular injection of 100 mg of pancuronium into each twin. Prior to MRI, 2 ml of a 0.0001 mmol/ml solution of gadolinium DTPA was also injected into the stomach of one twin. The contrast agent opacified the bowel loops of both twins, indicating bowel to bowel anastomosis. Following pregnancy termination, autopsy confirmed the prenatal diagnosis.  相似文献   
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Five alternative waste-derived fuels obtained from municipal solid waste and different post-consumer packaging were fed in a pilot-scale bubbling fluidized bed gasifier, having a maximum feeding capacity of 100 kg/h. The experimental runs utilized beds of natural olivine, quartz sand or dolomite, fluidized by air, and were carried out under various values of equivalence ratio. The process resulted technically feasible with all the materials tested. The olivine, a neo-silicate of Fe and Mg with an olive-green colour, has proven to be a good candidate to act as a bed catalyst for tar removal during gasification of polyolefin plastic wastes. Thanks to its catalytic activity it is possible to obtain very high fractions of hydrogen in the syngas (between 20% and 30%), even using air as the gasifying agent, i.e. in the most favourable economical conditions and with the simplest plant and reactor configuration. The catalytic activity of olivine was instead reduced or completely inhibited when waste-derived fuels from municipal solid wastes and aggregates of different post-consumer plastic packagings were fed. Anyhow, these materials have given acceptable performance, yielding a syngas of sufficient quality for energy applications after an adequate downstream cleaning.  相似文献   
17.
On beaches where natural shoreline variability is significant, beach nourishment is a useful engineering method to augment the dry beach and protect infrastructure and/or unstable cliffs. In this study, a low-cost video monitoring system is used to monitor the shoreline response to a nourishment operation on a dynamic gravel embayed beach in Central Italy. Video-derived shorelines were collected over a 15-month period to measure the evolution of the beach with regards to three specific parameters: the dry beach width, the dry beach area and the beach orientation. Moderate increases in the dry beach width of 3.6 m and 6.7 m across the embayment were observed in response to two different gravel nourishments of approximately 40,000 m3 and 46,000 m3 respectively. The orientation of the beach meanwhile was found to rotate rapidly in the clockwise direction and more gradually in the counter-clockwise direction. Analyses of individual storm events suggest these rapid clockwise rotations are caused by ESE storms, which result in beach retreat particularly at the southern end. The combination of an overall narrow beach width and a clockwise beach orientation is observed to cause a cliff erosion event at a vulnerable point along the embayment.  相似文献   
18.
The comparative effectiveness for hexavalent chromium removal from irrigation water, using two selected plant species (Phragmites australis and Ailanthus altissima) planted in soil contaminated with hexavalent chromium, has been studied in the present work. Total chromium removal from water was ranging from 55 % (Phragmites) to 61 % (Ailanthus). After 360 days, the contaminated soil dropped from 70 (initial) to 36 and 41 mg Cr/kg (dry soil), for Phragmites and Ailanthus, respectively. Phragmites accumulated the highest amount of chromium in the roots (1910 mg Cr/kg(dry tissue)), compared with 358 mg Cr/kg(dry tissue) for Ailanthus roots. Most of chromium was found in trivalent form in all plant tissues. Ailanthus had the lowest affinity for CrVI reduction in the root tissues. Phragmites indicated the highest chromium translocation potential, from roots to stems. Both plant species showed good potentialities to be used in phytoremediation installations for chromium removal.  相似文献   
19.
The main goal of the paper was to assess the pattern of risk factors having an impact on the onset of early wheezing phenotypes in the birth cohort of 468 two-year olds and to investigate the severity of respiratory illness in the two-year olds in relation to both wheezing phenotypes, environmental tobacco smoke (ETS) and personal PM2.5 exposure over pregnancy period (fine particulate matter). The secondary goal of the paper was to assess possible association of early persistent wheezing with the length of the baby at birth. Pregnant women were recruited from ambulatory prenatal clinics in the first and second trimester of pregnancy. Only women 18–35 years of age, who claimed to be non-smokers, with singleton pregnancies, without illicit drug use and HIV infection, free from chronic diseases were eligible for the study. In the statistical analysis of respiratory health of children multinomial logistic regression and zero-inflated Poisson regression models were used. Approximately one third of the children in the study sample experienced wheezing in the first 2 years of life and in about two third of cases (67%) the symptom developed already in the first year of life. The early wheezing was easily reversible and in about 70% of infants with wheezing the symptom receded in the second year of life. The adjusted relative risk ratio (RRR) of persistent wheezing increased with maternal atopy (RRR = 3.05; 95%CI: 1.30–7.15), older siblings (RRR = 3.05; 95%CI: 1.67–5.58) and prenatal ETS exposure (RRR = 1.13; 95%CI: 1.04–1.23), but was inversely associated with the length of baby at birth (RRR = 0.88; 95%CI: 0.76–1.01). The adjusted incidence risk ratios (IRR) of coughing, difficult breathing, runny/stuffy nose and pharyngitis/tonsillitis in wheezers were much higher than that observed among non-wheezers and significantly depended on prenatal PM2.5 exposure, older siblings and maternal atopy. The study shows a clear inverse association between maternal age or maternal education and respiratory illnesses and calls for more research efforts aiming at the explanation of factors hidden behind proxy measures of quality of maternal care of babies. The data support the hypothesis that burden of respiratory symptoms in early childhood and possibly in later life may be programmed already in prenatal period when the respiratory system is completing its growth and maturation.  相似文献   
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