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201.
The purpose of this study was to find out possible differences in prenatal diagnosis (PD) by amniocentesis or chorionic villus sampling and ultrasound examination before 16 weeks' gestation (early ultrasound examination, EUE), according to area of residence and level of education of the mothers. Data come from a multicentre study in Italy involving 43 maternity hospitals (Mercurio project) and were collected through structured interviews a few days after delivery. Study subjects were 1541 mothers of single non-malformed infants born between April 1992 and March 1994. Overall, the incidence of PD and EUE was 5.8 and 80 per cent, respectively. After adjustment for maternal age and other possible confounders, the odds ratios for PD were 2.19 (95 per cent confidence interval (CI)=1.26–3.81) when women residing in the northern regions were compared with those residing in the southern regions, and 2.06 (95 per cent CI=1.12–3.79) and 4.08 (95 per cent CI=1.97–8.42) when women with medium and high levels of education were compared with those with low level. For EUE, the odds ratios were 1.77 (95 per cent CI=1.32–2.36) and 2.88 (95 per cent CI=1.56–5.29) when comparing women with medium and high levels of education with those with low level. No relationship was found between area of residence and EUE. These geographical and social inequalities in prenatal care in Italy should be taken into account for the organization, delivery, and evaluation of pregnancy services in the coming years.  相似文献   
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To date, only a few attempts have been done to estimate the contribution of Mediterranean ecosystems to the global carbon cycle. Within this context, shrub species, composition and structure of the Mediterranean shrublands developing along the Latium coast (Italy) were analyzed in order to evaluate their contribution to carbon (C) sequestration, also taking into consideration the economic benefits at a national level. The considered shrublands had a shrub density of 1,200?±?500 shrubs ha?1. Shrubs were classified into small (S), medium (M) and large (L), according to their volume (V) and leaf area index (LAI). The total yearly carbon dioxide (CO2) sequestration per species (SCy) was calculated multiplying the total photosynthetic leaf surface area (spt) of each species by the mean yearly photosynthetic rate and the total yearly photosynthetic activity time (in hours). Q. ilex and A. unedo had the highest SCy (46.2?±?15.8 kg CO2 year?1, mean value), followed by P. latifolia (17.5?±?6.2 kg CO2 year?1), E. arborea, E. multiflora, C. incanus, P. lentiscus, R. officinalis, and S. aspera (6.8?±?4.2 kg CO2 year?1, mean value). The total yearly CO2 sequestration per shrub (SCshy) was 149?±?5 kg CO2 year?1 in L, decreasing 30 % in M and 80 % in S shrubs. Taking into account the frequency of S, M and L and their SCshy, the total CO2 sequestration of the Mediterranean maquis was quantified in 80 Mg CO2 ha?1?year?1, corresponding to 22 Mg C ha?1?year?1. From a monetary viewpoint, this quantity could be valued to more than 500 US$ ha?1?year?1. Extending this benefit to the Mediterranean shrublands throughout the whole country, we obtained a nationwide estimated annual benefit in the order of $500 million.  相似文献   
204.
Continuous measurements of the CO2 concentration were repeatedly carried out from 1996 to 2007 between Italy and New Zealand by means of a Siemens Ultramat 5E analyzer assembled for shipboard use. Along the ship routes discrete air samples were collected from 1998 to 2005 using four-litre Pyrex flasks. The δ13C of the CO2 from the flask air samples was measured according to well-established techniques. The decadal changes of these two variables can now be evaluated from these results. Large variations of the CO2 concentration were normally recorded in the Mediterranean and the Red Sea. Completely different trends of the CO2 concentration were observed in the Red Sea (30° N to about 13° N) between 2007 (a marked southward decrease) and 2005 and 2003 when a marked southward increase is apparent, at least between 23° and 13° N. A further difference among different expeditions is related to the decrease or increase of the CO2 concentration in the Gulf of Aden. The backward trajectories of the air masses help to explain, at least partially, these differences. In the Indian Ocean and Southern Ocean a decrease of a few ppmv of the CO2 concentration takes place from Cape Guardafui (Northern Somaliland) to southern New Zealand, particularly during 2005 and 2007. The yearly rate of increase of the CO2 concentration between 1996 and 2007 for the Indian Ocean is of about 1.9 ppmv yr?1, in excellent agreement with the NOAA/CMDL measurements carried out during the same period at Mahé Isld. (Indian Ocean) and Cape Grim (Tasmania). The δ13C results obtained from the CO2 of flask samples collected in the Mediterranean show the effect of anthropogenic emissions, though this is considerably smaller than expected. This inconsistency may be related to the large terrestrial biospheric sink of CO2 in the Northern Hemisphere. The results obtained from the Red Sea are quite variable through time and space, particularly in its southern section; their interpretation is not easy. The Indian Ocean and the Southern Ocean show rather homogeneous δ13C results even though a variable carbon isotope shift can be calculated from period/cruise to period/cruise. In the case of the Indian Ocean the mean δ13C value from the flask air samples collected in 2005 is ?8.29‰ and the calculated rate of the carbon isotope shift between 1998 and 2005 is ?0.034‰ yr?1, considerably larger than that calculated at the closest NOAA station (Mahé Isld.) of ?0.026‰ yr?1. This discrepancy may be, at least partially, caused by the small number of measurements carried out at sea. However, the atmosphere over the Indian Ocean is less affected by anthropogenic emissions than in other areas.  相似文献   
205.
Controlling invasive species presents a public-good dilemma. Although environmental, social, and economic benefits of control accrue to society, costs are borne by only a few individuals and organizations. For decades, policy makers have used incentives and sanctions to encourage or coerce individual actors to contribute to the public good, with limited success. Diverse, subnational efforts to collectively manage invasive plants, insects, and animals provide effective alternatives to traditional command-and-control approaches. Despite this work, there has been little systematic evaluation of collective efforts to determine whether there are consistent principles underpinning success. We reviewed 32 studies to identify the extent to which collective-action theories from related agricultural and environmental fields explain collaborative invasive species management approaches; describe and differentiate emergent invasive species collective-action efforts; and provide guidance on how to enable more collaborative approaches to invasive species management. We identified 4 types of collective action aimed at invasive species—externally led, community led, comanaged, and organizational coalitions—that provide blueprints for future invasive species management. Existing collective-action theories could explain the importance attributed to developing shared knowledge of the social-ecological system and the need for social capital. Yet, collection action on invasive species requires different types of monitoring, sanctions, and boundary definitions. We argue that future government policies can benefit from establishing flexible boundaries that encourage social learning and enable colocated individuals and organizations to identify common goals, pool resources, and coordinate efforts.  相似文献   
206.
A new biotechnological synthetic approach to 4-hydroxybenzoic acid is reported. Thauera aromatica cells produce the phenylphosphate carboxylase enzyme that selectively carboxylates phenylphosphate in the para position, without any formation of the ortho isomer. Here we show that the enzyme also works in supercritical carbon dioxide, opening a new technological solution to the recovery of the products that is a key problem when aqueous media are used. The enzyme shows an activity comparable with that shown under CO2 pressure in aqueous media and does not require the presence of NaHCO3.  相似文献   
207.
We report a case of nuchal cystic hygroma with spontaneous resolution detected by ultrasound examination at 13 weeks' gestation. Fetal karyotype and amniotic fluid alphafetoprotein levels were normal. Extreme caution in evaluating this situation is stressed.  相似文献   
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Five arsenic-resistant bacterial strains designated MT1, MT2, MT3, V1 and V2 were isolated from sediments of the Oliveri-Tindari Lagoon (Italy), which comprises six small lakes whose sediments contain low arsenic concentrations. Phylogenetic analysis of the 16S rRNA gene sequences assigned them to the genus Bacillus. Bacillus sp. strain MT3 showed higher tolerance to As(III) and As(V), as indicated by minimum inhibitory concentrations of 14 and 135 mmol?1, respectively. Bacillus sp. strain V1 showed growth inhibition at 14 mmol?1 in the presence of As(III) and at 68 mmol?1 in the presence of As(V), whereas the arsenic resistance of Bacillus sp. strain MT1 was 10 and 27 mmol?1 for As(III) and As(V), respectively. The strains Bacillus spp. MT2 and V2 showed low levels of As(III) and As(V) resistance, as it was unable to grow at concentrations>7 and 14 mmol?1, respectively. The isolated arsenic-resistant Bacillus spp. strains were able to reduce As(V) to As(III), especially Bacillus spp. strain MT3. This study suggests that the isolated bacterial strains play a role in the arsenic biogeochemical cycle of arsenic-poor sediments in the Oliveri-Tindari Lagoon.  相似文献   
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