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1.
Sci Total Environ ; 612: 202-213, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28850839

RESUMO

Comparison of fine and coarse fractions in terms of sources and dynamics is scarce in southeast Mediterranean countries; differences are relevant because of the importance of natural sources like sea spray and Saharan dust advection, because most of the monitoring networks are limited to PM10. In this work, the main seasonal variabilities of sources and processes involving fine and coarse PM (particulate matter) were studied at the Environmental-Climate Observatory of Lecce (Southern Italy). Simultaneous PM2.5 and PM10 samples were collected between July 2013 and July 2014 and chemically analysed to determine concentrations of several species: OC (organic carbon) and EC (elemental carbon) via thermo-optical analysis, 9 major ions via IC, and 23 metals via ICP-MS. Data was processed through mass closure analysis and Positive Matrix Factorization (PMF) receptor model characterizing seasonal variabilities of nine sources contributions. Organic and inorganic secondary aerosol accounts for 43% of PM2.5 and 12% of PM2.5-10 with small seasonal changes. SIA (secondary inorganic aerosol) seasonal pattern is opposite to that of SOC (secondary organic carbon). SOC is larger during the cold period, sulphate (the major contributor to SIA) is larger during summer. Two forms of nitrate were identified: NaNO3, correlated with chloride depletion and aging of sea-spray, mainly present in PM2.5-10; NH4NO3 more abundant in PM2.5. Biomass burning is a relevant source with larger contribution during autumn and winter because of the influence of domestic heating, however, is not negligible in spring and summer, because of the contributions of fires and agricultural practices. Mass closure analysis and PMF results identify two soil sources: crustal associated to long range transport and carbonates associated to local resuspended dust. Both sources contributes to the coarse fraction and have different dynamics with crustal source contributing mainly in high winds from SE conditions and carbonates during high winds from North direction.

2.
Environ Pollut ; 184: 597-604, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24212180

RESUMO

We analysed the variability of equivalent black carbon (BC) and ozone (O3) at the global WMO/GAW station Nepal Climate Observatory-Pyramid (NCO-P, 5079 m a.s.l.) in the southern Himalayas, for evaluating the possible contribution of open vegetation fires to the variability of these short-lived climate forcers/pollutants (SLCF/SLCP) in the Himalayan region. We found that 162 days (9% of the data-set) were characterised by acute pollution events with enhanced BC and O3 in respect to the climatological values. By using satellite observations (MODIS fire products and the USGS Land Use Cover Characterization) and air mass back-trajectories, we deduced that 56% of these events were likely to be affected by emissions from open fires along the Himalayas foothills, the Indian Subcontinent and the Northern Indo-Gangetic Plain. These results suggest that open fire emissions are likely to play an important role in modulating seasonal and inter-annual BC and O3 variability over south Himalayas.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Incêndios , Ozônio/análise , Fuligem/análise , Poluição do Ar/estatística & dados numéricos , Nepal
3.
Sci Total Environ ; 445-446: 155-64, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23333511

RESUMO

Halogenated gases potentially harmful to the stratospheric ozone layer are monitored worldwide in order to assess compliance with the Montreal Protocol requiring a phase out of these compounds on a global scale. We present the results of long term (2002-2011) continuous observation conducted at the Mt. Cimone GAW Global Station located on the highest peak of the Italian Northern Apennines, at the border of two important regions: the Po Valley (and the Alps) to the North and the Mediterranean Basin to the South. Bi-hourly air samples of CFC-12, CFC-11, CFC-114, CFC-115, H-1211, H-1301, methyl chloroform, carbon tetrachloride, HCFC-22, HCFC-142b, HCFC-124 and methyl bromide are collected and analysed using a gas chromatograph-mass spectrometer, providing multi annual time series. In order to appreciate the effectiveness of the Montreal Protocol from a regional perspective, trends and annual growth rates of halogenated species have been calculated after identification of their baseline values. A comparison with results from other international observation programmes is also presented. Our data show that the peak in the atmospheric mixing ratios of four chlorofluorocarbons, two halons and two chlorocarbons has been reached and all these species now show a negative atmospheric trend. Pollution episodes are still occurring for species like halon-1211, methyl chloroform and carbon tetrachloride, indicating fresh emissions from the site domain which could be ascribed both to fugitive un-reported uses of the compounds and/or emissions from banks. For the hydrofluorocarbons changes in the baseline are affected by emissions from fast developing Countries in East Asia. Fresh emissions from the site domain are clearly declining. Methyl bromide, for which the Mediterranean area is an important source region, shows, in a generally decreasing trend, an emission pattern that is not consistent with the phase-out schedule of this compound, with a renewed increase in the last two years of pollution episodes.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/química , Monitoramento Ambiental , Poluição Ambiental/análise , Perda de Ozônio , Poluentes Atmosféricos/química , Clorofluorcarbonetos/análise , Clorofluorcarbonetos/química , Poluição Ambiental/legislação & jurisprudência , Poluição Ambiental/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas , Aquecimento Global , Halogenação , Hidrocarbonetos Halogenados/análise , Hidrocarbonetos Halogenados/química , Itália
4.
J Environ Sci (China) ; 25(8): 1618-25, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24520700

RESUMO

To study the influence of polluted air-mass transport carrying ozone (O3) and black carbon (BC) in the high Himalayas, since March 2006 the Nepal Climate Observatory at Pyramid (NCO-P) GAW-WMO global station (Nepal, 5079 m a.s.l.) is operative. During the first 5-year measurements, the O3 and BC concentrations have shown a mean value of 48 +/- 12 ppb (+/- standard deviation) and 208 +/- 374 ng/m3, respectively. Both O3 and BC showed well defined seasonal cycles with maxima during pre-monsoon (O3: 61.3 +/- 7.7 ppbV; BC: 444 +/- 433 ng/m3) and minima during the summer monsoon (O3: 40.1 +/- 12.4 ppbV; BC: 64 +/- 101 ng/m3). The analysis of the days characterised by the presence of a significant BC increase with respect to the typical seasonal cycle identified 156 days affected by "acute" pollution events, corresponding to 9.1% of the entire data-set. Such events mostly occur in the pre-monsoon period, when the O3 diurnal variability is strongly related to the transport of polluted air-mass rich on BC. On average, these "acute" pollution events were characterised by dramatic increases of BC (352%) and O3 (29%) levels compared with the remaining days.


Assuntos
Poluentes Atmosféricos/análise , Carbono/análise , Ozônio/análise , Nepal
5.
Ultrasound Obstet Gynecol ; 35(1): 35-41, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20020466

RESUMO

OBJECTIVE: To present antenatal sonographic findings and outcome of fetuses with hypoplasia or partial agenesis of the corpus callosum. METHODS: The database of our ultrasound laboratory was searched retrospectively for cases of hypoplasia or partial agenesis of the corpus callosum suspected at antenatal neurosonography between 1998 and 2008 and confirmed by pathology or postnatal neuroimaging. In surviving infants, clinical follow-up had been arranged to assess neurodevelopmental outcome. RESULTS: Nineteen fetuses with callosal underdevelopment were identified at a median gestational age of 22 (range, 21-33) weeks and confirmed at follow-up, including 14 with partial agenesis and five with hypoplasia. Among the 14 fetuses with partial agenesis, there were additional brain findings in 10, including two with absent cavum septi pellucidi, four with mild isolated ventriculomegaly and four with cerebellar abnormalities, two of which also had ventriculomegaly. Pregnancy was terminated electively in seven of the cases with partial agenesis and there was one neonatal death. Among the six surviving infants, neurodevelopmental outcome was appropriate for age in three at follow up, including two cases with isolated partial agenesis of the corpus callosum. Among the five fetuses with prenatally diagnosed callosal hypoplasia, additional anomalies were present in four. Two cases were terminated electively and three were alive at the time of writing, with a median age of 3 years. Among them, apparently normal neurological development was observed in only one case. CONCLUSIONS: An antenatal diagnosis of callosal underdevelopment is possible by expert sonography. There is often association with other major anomalies. However, even in fetuses with apparently isolated findings, the prognosis is uncertain.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Agenesia do Corpo Caloso , Doenças Fetais/diagnóstico por imagem , Anormalidades Múltiplas/mortalidade , Anormalidades Múltiplas/patologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Feminino , Doenças Fetais/mortalidade , Doenças Fetais/patologia , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos , Ultrassonografia
6.
Ultrasound Obstet Gynecol ; 34(4): 416-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19697393

RESUMO

OBJECTIVE: To investigate the clinical implications of two categories of fetal bilateral cleft lip and palate (BCLP): with premaxillary protrusion and with a flattened profile. METHODS: This was a retrospective study of fetuses with a prenatal diagnosis of BCLP at the Department of Obstetrics and Gynecology of the University of Bologna in the period 1991-2005. RESULTS: BCLP was diagnosed prenatally in 14 cases (mean gestational age at diagnosis, 21 (range, 12-36) weeks). In nine of these, there was a premaxillary pseudomass; in the remaining five, the profile was flat. Associated structural and/or chromosomal anomalies were found in two of the nine with a premaxillary pseudomass and in all five of those with a flat profile (P = 0.02). All fetuses with a flat profile had aneuploidies (three trisomy 18, one trisomy 13, one trisomy 8 mosaic), as did one of the nine with a premaxillary pseudomass. Eight of the pregnancies were terminated, including three of those with a premaxillary pseudomass and all five of those without. All continuing pregnancies resulted in live births, although one neonate affected by Krabbe's disease died shortly after birth. CONCLUSIONS: Our findings suggest that a third of cases of BCLP diagnosed in utero have a flat profile and these are at high risk of lethal aneuploidies.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Aneuploidia , Fenda Labial/diagnóstico por imagem , Fissura Palatina/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Maxila/diagnóstico por imagem , Anormalidades Múltiplas/embriologia , Anormalidades Múltiplas/mortalidade , Fenda Labial/embriologia , Fenda Labial/mortalidade , Fissura Palatina/embriologia , Fissura Palatina/mortalidade , Feminino , Doenças Fetais/mortalidade , Idade Gestacional , Humanos , Recém-Nascido , Maxila/anormalidades , Maxila/embriologia , Gravidez , Prognóstico , Estudos Retrospectivos , Ultrassonografia Pré-Natal
8.
Sci Total Environ ; 391(2-3): 252-61, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18061647

RESUMO

In this work we present the new ABC-Pyramid Atmospheric Research Observatory (Nepal, 27.95 N, 86.82 E) located in the Himalayas, specifically in the Khumbu valley at 5079 m a.s.l. This measurement station has been set-up with the aim of investigating natural and human-induced environmental changes at different scales (local, regional and global). After an accurate instrumental set-up at ISAC-CNR in Bologna (Italy) in autumn 2005, the ABC-Pyramid Observatory for aerosol (physical, chemical and optical properties) and trace gas measurements (ozone and climate altering halocarbons) was installed in the high Khumbu valley in February 2006. Since March 2006, continuous measurements of aerosol particles (optical and physical properties), ozone (O3) and meteorological parameters as well as weekly samplings of particulate matter (for chemical analyses) and grab air samples for the determination of 27 halocarbons, have been carried out. These measurements provide data on the typical atmospheric composition of the Himalayan area between India and China and make investigations of the principal differences and similarities between the monsoon and pre-monsoon seasons possible. The study is carried out within the framework of the Ev-K2-CNR "SHARE-Asia" (Stations at High Altitude for Research on the Environment in Asia) and UNEP-"ABC" (Atmospheric Brown Clouds) projects. With the name of "Nepal Climate Observatory-Pyramid" the station is now part of the Observatory program of the ABC project.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Halogenados/análise , Ozônio/análise , Material Particulado/análise , Fuligem/análise , Aerossóis , Altitude , Monitoramento Ambiental , Nepal , Estações do Ano , Tempo (Meteorologia)
9.
Ultrasound Obstet Gynecol ; 28(7): 899-903, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17086581

RESUMO

OBJECTIVE: To identify criteria useful for differentiating closed from open spina bifida antenatally. PATIENTS AND METHODS: A retrospective study of cases of spina bifida diagnosed in a referral center between 1997 and 2004. RESULTS: Of 66 cases of fetal spina bifida diagnosed at a median gestational age of 21 (range, 16-34) weeks, detailed follow-up was available for 57. Of these, open defects were found in 53 (93.0%) and closed defects in four (7.0%). Closed spina bifida was associated in two cases with a posterior cystic mass with thick walls and a complex appearance, while in two cases the spinal lesion could not be clearly differentiated from an open defect, particularly at mid-gestation. Open spina bifida was always associated with typical alterations of cranial anatomy, including the so-called 'banana' and 'lemon' signs, while in closed spina bifida the cranium was unremarkable. When the data were available, levels of amniotic fluid alpha-fetoprotein were always abnormally elevated with open spina bifida and within normal limits with closed forms. CONCLUSION: In this study 7% of cases of spina bifida diagnosed in utero were closed. The differentiation between open and closed forms is best shown by the sonographic demonstration of abnormal or normal cranial anatomy.


Assuntos
Doenças Fetais/diagnóstico , Diagnóstico Pré-Natal/métodos , Disrafismo Espinal/diagnóstico , Ultrassonografia Pré-Natal/métodos , Diagnóstico Diferencial , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Gravidez , Estudos Retrospectivos , Disrafismo Espinal/embriologia
10.
Transplant Proc ; 38(6): 1844-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16908301

RESUMO

The aim of the study was to evaluate the use of Surgisis (Cook Biotech Inc.), a porcine derived extracellular matrix already used in tissue engineering, as a scaffold for neointestinal regeneration in a rat model. A 3-cm length of tubular Surgisis graft was interposed with bilateral anastomoses in the middle of an isolated ileal loop of Sprague Dawley rats with an ileostomy. The grafts were harvested and analyzed using histology and immunohistochemistry at 24 weeks after operation. Macroscopic examination revealed neither stenosis nor adhesions in the area surrounding the neointestine. The regenerated small bowel showed a mean shrinkage of 30.7% (range 20%-40%). Histologic and immunohistochemical evaluation showed a well-developed three layers of mucosa and smooth muscle and serosa in the regenerated bowel wall that were similar to those of the normal bowel with evident neovascularization. Also, the regeneration of smooth muscle fibers and innervation were evident. The preliminary results of this study showed that Surgisis allowed rapid regeneration of mucosa and smooth muscle and therefore may be a promising material for the creation of a neointestine.


Assuntos
Intestino Delgado/transplante , Regiões de Interação com a Matriz/fisiologia , Anastomose Cirúrgica , Animais , Ileostomia , Íleo/cirurgia , Intestino Delgado/fisiologia , Masculino , Modelos Animais , Ratos , Ratos Sprague-Dawley , Regeneração , Suínos , Engenharia Tecidual/métodos , Coleta de Tecidos e Órgãos/métodos
11.
Ultrasound Obstet Gynecol ; 27(5): 517-21, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16586472

RESUMO

OBJECTIVE: To assess the feasibility of the prenatal diagnosis using fetal neurosonography of brain injuries in the surviving fetus after the demise of a monochorionic cotwin. METHODS: This was a retrospective observational study in the period 1990-2004 of monochorionic twin pregnancies with a single fetal demise. A detailed sonographic evaluation of the intracranial anatomy of the surviving twin had been performed whenever possible using a multiplanar approach and from 1999, fetal magnetic resonance imaging was offered as well. Postnatal follow-up was obtained in all cases. RESULTS: In six of nine cases, abnormal neurosonographic findings were identified including intracranial hemorrhage, brain atrophy, porencephaly and periventricular echogenicities evolving into polymicrogyria. Prenatal diagnosis of brain lesions was confirmed postnatally and all affected infants who survived had severe neurological sequelae. Two fetuses had normal cerebral structures both on the prenatal neurosonogram and on postnatal imaging and were following normal developmental milestones, one at 1 and the other at 5 years of age. In one case the neurosonographic examination was suboptimal and the infant was found at birth to have a porencephalic cyst. Fetal magnetic resonance imaging was performed in two cases and confirmed the ultrasound diagnosis. CONCLUSIONS: Prenatal neurosonography is a valuable tool for the prediction of neurological outcome in fetuses surviving after the intrauterine death of a monochorionic cotwin. Although our experience is limited, we suggest that magnetic resonance imaging should also be offered.


Assuntos
Encefalopatias/diagnóstico por imagem , Encefalopatias/embriologia , Doenças em Gêmeos/diagnóstico por imagem , Doenças em Gêmeos/embriologia , Ecoencefalografia , Ultrassonografia Pré-Natal , Desenvolvimento Infantil , Feminino , Morte Fetal , Seguimentos , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Gravidez , Segundo Trimestre da Gravidez , Prognóstico , Estudos Retrospectivos , Gêmeos Monozigóticos
12.
Ultrasound Obstet Gynecol ; 27(5): 522-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16586477

RESUMO

OBJECTIVE: To investigate the effectiveness of a simplified approach to the evaluation of the midline structures of the fetal brain using three-dimensional (3D) ultrasound. METHODS: Sonographic examinations were performed in normal fetuses and in cases with anomalies involving the midline cerebral structures. Two-dimensional (2D) median planes were obtained by aligning the transducer with the anterior fontanelle and midline sutures by either transabdominal or transvaginal scans. Median planes were also reconstructed using 3D ultrasonography from volumes acquired from transabdominal axial planes of the fetal head (3D median planes), by either multiplanar analysis of static volumes or volume contrast imaging in the coronal plane (VCI-C). 2D and 3D median planes were compared qualitatively and quantitatively by measuring the corpus callosum and cerebellar vermis. RESULTS: 2D median planes could be visualized in 54/56 normal fetuses. 3D median planes were obtained in all, usually more easily and rapidly. There was a good correlation between 2D and 3D images. Measurements of the corpus callosum and cerebellar vermis were highly correlated, with mean variations of 6% and 14%, respectively. The abnormal group included 13 fetuses (five with partial or complete agenesis of the corpus callosum, six with posterior fossa malformations, two with a combination of these two anomalies). In all cases the diagnosis could be made by both 2D and 3D views and was always confirmed by postnatal investigation. Although 2D median views were of better quality, 3D images were always adequate for diagnosis, both in normal and abnormal fetuses. CONCLUSIONS: 3D median planes are obtained more easily than 2D ones, and allow an accurate diagnosis of normal cerebral anatomy and anomalies. The 3D approach may be valuable particularly for rapid assessment of fetal cerebral anatomy in standard examinations.


Assuntos
Encéfalo/anormalidades , Ecocardiografia Tridimensional , Ultrassonografia Pré-Natal , Agenesia do Corpo Caloso , Cerebelo/anormalidades , Cisterna Magna/anormalidades , Ecocardiografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Sensibilidade e Especificidade
13.
J Environ Pathol Toxicol Oncol ; 16(2-3): 239-44, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9276009

RESUMO

An extensive research program to record atmospheric physicochemical parameters and to track climatological trends was established at a remote Alpine station at Mt. Cimone Observatory in Italy. The main features of the study are outlined briefly and the results thus far collected, including surface ozone, carbon dioxide, stratospheric NO2 and O3, and airborne radioactivity are provided.


Assuntos
Atmosfera/análise , Dióxido de Carbono/análise , Dióxido de Nitrogênio/análise , Ozônio/análise , Radioisótopos/análise , Berílio/análise , Itália , Radônio/análise
14.
Appl Opt ; 34(15): 2737-44, 1995 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21052419

RESUMO

Our institute has recently developed a differential optical absorption spectrometry system called the gas analyzer spectrometer correlating optical absorption differences (GASCOAD), which features as a detector a linear image sensor that uses an artificial light source for long-path tropospheric-pollution monitoring. The GASCOAD, its method of eliminating interference from background sky light, and subsequent spectral analysis are reported and discussed. The spectrometer was used from 7 to 22 February 1993 in Milan, a heavily polluted metropolitan area, to measure the concentrations of SO(2), NO(2), O(3), and HNO(2) averaged over a 1.7-km horizontal light path. The findings are reported and briefly discussed.

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