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991.
Among the myriad particles the human respiratory tract is exposed to, a significant number are distinctive in that they include humic substances (HS) and humic-like substances (HULIS) as organic components. HS are heterogeneous, amorphous, organic materials which are ubiquitous occurring in all terrestrial and aqueous environments. HULIS are a complex class of organic, macromolecular compounds initially extracted from atmospheric aerosol particles which share some features with HS including an aromatic, polyacidic nature. As a result of having a variety of oxygen-containing functional groups, both HS and HULIS complex metal cations, especially iron. Following particle uptake by cells resident in the lung, host iron will be sequestered by HS- and HULIS-containing particles initiating pathways of inflammation and subsequent fibrosis. It is proposed that (1) human exposures to HS and HULIS of respirable size (<10 µm diameter) are associated with inflammatory and fibrotic lung disease and (2) following retention of particles which include HS and HULIS, the mechanism of cell and tissue injury involves complexation of host iron. Human inflammatory and fibrotic lung injuries following HS and HULIS exposures may include coal workers’ pneumoconiosis, sarcoidosis, and idiopathic pulmonary fibrosis as well as diseases associated with cigarette smoking and exposures to emission and ambient air pollution particles.  相似文献   
992.
The mineral and chemical composition of the liquid and lithogenous substances, consumed by the wild ungulate animals, at the kudurs of the Teletskoye Lake, Gorny Altai, Russia, was studied. It was investigated that all examined kudurits are argillous-aleurolitic and get in the interval from 1 to 100 μm with the predominance of the fraction 10 μm. By the mineral composition, the lithogenous kudurits present the quartz-feldspathic-hydromicaceous-chloritic mineral formations with the large content of the quartz particles (20–43%) and sodium-containing plagioclases (albite, 15–32 wt%). The lithogenous kudurits are the products of the reconstitution of the metamorphic cleaving stones as a result of the glacier abrasive effect, subsequent its aqueous deposits and then eolation in the subaerial conditions. The fontinal waters consumed at the kudurs are subsaline chloride-hydrocarbonate-sodium and sulphated-hydrocarbonate-calcium types. It essentially differs by the increased content of rare-earth elements in reference to the lake water. The acid (HCl, pH-1) extracts from the kudurits more actively extract calcium (10–35% of the gross contents; sodium extracts at the level of 1–3%). The most fluent in the microelements composition are Cu, Be, Sr, Co, Cd, Pb, Sc, Y and rare-earth elements. The transit of all these elements into the dissoluted form fluctuates about 10% from the gross contents. The reason of geophagy is related to tendency of herbivores to absorb mineralized subsoils enriched by the biologically accessible forms of rare-earth elements, arisen as a result of vital activity of specific microflora.  相似文献   
993.
The identification of geographical origin of food products is important for both consumers and producers to ensure quality and avoid label falsifications. The caper plant (Capparis spinosa L., Brassicales Capparidaceae), a xerophytic shrub common in the Mediterranean area, produces buds and fruits that are commercialized in brine at high price. Those grown in Italy in the Aeolian Islands are renowned for their high quality. This study is aimed to establish a correlation between the geological and geochemical features of soil and the chemical composition of caper buds grown in two Aeolian Islands, Lipari and Salina. Major and trace elements were investigated by X-ray fluorescence and inductively coupled plasma-mass spectrometry in soil and caper samples from three localities in Lipari and Salina, and data from the three sites were compared by a nonparametric test, a correlation test and multivariate statistics (principal component analysis). The results allowed to discriminate soils according to geolithological characteristics of each area and detect a statistically significant correspondence between soil and caper samples for the elements Co, Fe, Mg and Rb, identifying thus possible geochemical caper fingerprints of origin. These results may also be useful to protect the high quality of Aeolian caper products by a suitable “Made in Italy” trademark and avoid falsifications and frauds.  相似文献   
994.
Quality of groundwater in the Yarmouk basin, Jordan has been assessed through the study of hydrogeochemical characteristics and the water chemistry as it is considered the main source for drinking and agriculture activities in the region. The results of the relationship between Ca2+ + Mg2+ versus HCO3? + CO32?, Ca2+ + Mg2+ versus total cations, Na+ + K+ versus total cations, Cl? + SO42? versus Na+ + K+, Na+ versus Cl?, Na+ versus HCO3? + CO32?, Na+ versus Ca2+, and Na+: Cl? versus EC describe the mineral dissolution mechanism through the strong relationship between water with rocks in alkaline conditions with the release of Ca2+, Mg2+, Na+, K+, HCO3?, CO32?, SO42?, and F? ions in the groundwater for enrichment. Furthermore, evaporation processes, groundwater depletion, and ion exchange contribute to the increased concentration of Na+ and Cl? ions in groundwater. Anthropogenic sources are one of the main reasons for contamination of groundwater in the study area and for increasing the concentration of Mg2+, Na+, Cl?, SO42?, and NO3? ions. Results show the quality of groundwater in the study area is categorized as follows: HCO3? + CO32? > Cl? > SO42? > NO3? > F? and Na+ > Ca2+ > Mg2+ > K+. In conclusion, the results of TDS, TH, and chemical composition showed that 26% of the groundwater samples were unsuitable for drinking. About 28% of groundwater samples in the study area have a high concentration of Mg2+, Na+, and NO3? above the acceptable limit. Also, based on high SAR, 10% of the groundwater samples were not suitable for irrigation purposes.  相似文献   
995.
The junction area of Yunnan, Guizhou, and Sichuan provinces is the heaviest coal-burning endemic fluorosis zones in China. To better understand the pathogenicity of endemic fluorosis in this area, 87 coal samples from the late Permian outcrop or semi-outcrop coal seams were collected in eight counties of the junction area of Yunnan, Guizhou, and Sichuan provinces. The total fluorine and sulfate content, etc. in the coal was determined using combustion-hydrolysis/fluoride-ion-selective electrode method and ion chromatography, respectively. The results show that the total fluorine concentrations in the samples ranged from 44 to 382 µg g?1, with an average of 127 µg g?1. The average pH of the coals is 5.03 (1.86–8.62), and the sulfate content varied from 249 to 64,706 µg g?1 (average 7127 µg g?1). In addition, the coals were medium- and high-sulfur coals, with sulfur mass fraction ranging from 0.08 to 13.41%. By heating the outcrop coals, HF release from the coal was verified quantitatively without exception, while simulated combustion directly confirmed the release of sulfuric acid (H2SO4). The acid in coal may be in the form of acidic sulfate (\({\text{HSO}}_{4}^{ - }\)/H2SO4) because of a positive relationship between pH and \(p\left( {{\text{SO}}_{4}^{2 - } } \right)\) in the acidic coal. The possible reaction mechanism would be that a chemical reaction between the acid (H2SO4 or \({\text{HSO}}_{4}^{ - }\)) and fluorine in the coal occurred, thereby producing hydrogen fluoride (HF), which would be the chemical form of fluorine released from coal under relatively mild conditions. The unique chemical and physical property of HF may bring new insight into the pathogenic mechanism of coal-burning endemic fluorosis. The phenomenon of coal-burning fluorosis is not limited to the study area, but is common in southwest China and elsewhere. Further investigation is needed to determine whether other endemic fluorosis areas are affected by this phenomenon.  相似文献   
996.
In this study, indoor and outdoor radon (222Rn) surveys were carried out in the summer and winter seasons in homes of one hundred lung cancer patients in the year 2013–2014. The aim was to investigate the relationship between radon and cancer patients. Lung cancer patients completed a questionnaire concerning their living environment, various physical parameters and living habits. Pearson correlation and t tests revealed no meaningful results between radon concentrations, on one hand, and environmental and personal living habits, on the other hand. Consequently, the BEIR VI model was adapted and 222Rn exposure was estimated to be responsible for about 12% of the lung cancer incidences in the winter season and around 5% in the summer season in the Rize Province. However, due to the limited number of data and numerous parameters that could lead to lung cancer, the estimations done with the model should be taken very lightly. The annual effective doses due to inhalation of indoor and outdoor 222Rn were estimated to be, respectively, 1.43 and 0.94 mSv y?1. The indoor and outdoor annual effective doses were, respectively, close and below the world annual effective dose (1.3 mSv y?1). At the district level, the indoor annual effective dose equivalent in the ?yidere district was 4.52 mSv y?1, which was 3.5 times greater than the world average. The number of patients in the majority of the houses in this district was more than one.  相似文献   
997.
A new spatially balanced sampling design for environmental surveys is introduced, called Halton iterative partitioning (HIP). The design draws sample locations that are well spread over the study area. Spatially balanced designs are known to be efficient when surveying natural resources because nearby locations tend to be similar. The HIP design uses structural properties of the Halton sequence to partition a resource into nested boxes. Sample locations are then drawn from specific boxes in the partition to ensure spatial diversity. The method is conceptually simple and computationally efficient, draws spatially balanced samples in two or more dimensions and uses standard design-based estimators. Furthermore, HIP samples have an implicit ordering that can be used to define spatially balanced over-samples. This feature is particularly useful when sampling natural resources because we can dynamically add spatially balanced units from the over-sample to the sample as non-target or inaccessible units are discovered. We use several populations to show that HIP sampling draws spatially balanced samples and gives precise estimates of population totals.  相似文献   
998.
A study on the modern dynamics and shoreline changes from 1954 to 2014 of the Molise coast (central Adriatic Sea) has been carried out. Short to long-term shoreline changes and associated surface area variations have been assessed in GIS environment for the study coast, subdivided in nine coastal segments (S1-S9), by using 100-m regularly spaced transects. In addition, the possible influence of natural and anthropogenic factors, especially of climatic variability and engineered shoreline defense structures, has been investigated. The Molise coast has experienced notable long-term erosion (period 1054-2014) that caused an overall coastal land loss of approximately 940,000 m2. Erosion was, yet, limited to coastal segments S1 and S7, nearest to the mouths of major rivers, namely Trigno and Biferno, while the major part of the study coast has remained essentially stable or even advanced. Increased shoreline protection by defense structures has generally favoured shoreline stability and frequently generated shoreline advance, except for segments S1 and S7. Observed differences in shoreline change rates over time at the decadal to interannual scale, have not find a response in the analysis of available data on meteo-marine conditions of the Molise coast and climate variability indices, pointing out the need to improve knowledge on meteomarine conditions and on climatic variability forcing of the study area. From 2004 to 2014, the Molise shoreline remained essentially stable. Nonetheless, most recent shoreline changes (period 2011-2014) and modern shoreline dynamics indicate that erosion has become more widespread, involving at least part of segments S2-S3 and S8-S9, located south of the river mouth segments. The localized long-term shoreline retreat and most recent shoreline erosion appear to be primarily related to channel adjustments of the Biferno and Trigno rivers that occurred since the 1950s under the control of human interventions on the rivers, especially the construction respectively of a dam and a check dam along their lower courses, that trap of most of their solid load, affecting so adversely the sediment budget of the river mouths areas and adjacent beaches. Overall data acquired on the recent shoreline evolution and modern shoreline dynamics of the Molise coast and on related causal factors provide a good basic knowledge for regional coastal management purposes, and for further scientific purposes. Particularly, they suggest the opportunity to deepen a number of aspects such as the relationship between the coast and river catchments feeding it, the possible influences on the Molise shoreline dynamics of the neighbouring coasts, the efficiency/obsolescence of defense structures and the present-day vulnerability to coastal erosion of the Molise coast.  相似文献   
999.
Landslides affecting the north-western coast of the Island of Malta have been investigated and monitored for 10 years. As a result of a bathymetric survey, it was discovered the deposits continued out onto the seafloor, thus raising questions as to the timing of their development. Furthermore it was uncertain as to which environment they developed in and which factors controlled their movements. The aim of this paper is to investigate representative detachments to chronologically constrain these mass movement events and outline their spatial and temporal evolution. Samples for exposure dating using the cosmogenic nuclide 36Cl were collected from head scarps and blocks located within two long-term monitored landslides characterised by extensive block slides. The results indicate the oldest dated block detachment occurring in a subaerial environment at ca. 21 ka, when the sea level was about 130 m lower than at present. Mass movement possibly accelerated when sea level reached the landslide toe during the post-glacial marine transgression. Considering the timing of block movement, the landslide deposits observed today appear to be related to a first-time failure involving a large part of the slope, though and alternative hypothesis is also taken here into account. This main event is likely to have been followed by secondary movements influenced by toe undercutting and clay saturation due to rising sea level. However, further research on mass movement kinematics is required in order to model their evolution and explore whether this interpretation is widely applicable along the Maltese coast.  相似文献   
1000.
Portuguese coastal areas are of current major concern due to the continuous expansion of a strong urbanization, accentuated development of economic activities, resilient land use and general population growth. A particular attention has been given to the shoreline evolution, pointing out evidences of critical coastal sectors that are prone to suffer adverse consequences of climate changes direct impacts. Areas where climate change and sea-level rise effects will be stronger include, among others, coastal sectors associated to soft rocky or mobile substrate shores and/or low morphological shores with recognized marked erosion trend. Within this context, the knowledge of the geological setting is imperative as different lithologies have distinct resistance and behavior against marine erosion. The available digital geological Portuguese cartography at 1:25000 scale is not suitable to well characterize the geology within the context of small geographic areas or within the perspective of costal management. Hence, the National Laboratory of Energy and Geology (LNEG) developed a prototype to evaluate the potential of the integrated “geological and coastal hazard mapping” at a 1:3000 resolution scale. The combination of detailed geology and historical coastline displacement information, in a single map, constitute a new and valuable cartographic product to support coastal managers and general users of littoral regions. The application of the prototype to the entire Portuguese coastal areas will be carried out by LNEG and digital information will be available at LNEG GeoPortal (http://geoportal.lneg.pt/).  相似文献   
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