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11.
Soil Bioremediation: Combination of Earthworms and Compost for the Ecological Remediation of a Hydrocarbon Polluted Soil 总被引:1,自引:0,他引:1
Brunello Ceccanti Grazia Masciandaro Carlos Garcia Cristina Macci Serena Doni 《Water, air, and soil pollution》2006,171(1-4):383-397
A three-dimensional (3D) off-line chemical transport model (CTM) has been used to study an Arctic ozone minihole event in early December 2002, when the meteorological conditon were severely colder than in recent years. The minimum temperatures were below 188 K on 6 December 2002 and remained below 195 K for the entire month. Such temperatures are low enough for the formation of PSCs (polar stratospheric clouds) which were observed by a visible/near infrared solar occultation instrument by the Polar Ozone and Aerosol Measurement (POAM) III experiment. The SLIMCAT model compares well with the depth and evolution of the ozone distribution as observed by the second European Remote Sensing Satellite (ERS-2) Global Ozone Monitoring Experiment (GOME). The combined effect of a very strong and large intrusion of sub-tropical air, and uplifting of air masses of low ozone concentrations from the troposphere plays important role in the fomation of the ozone minihole. The modelled chemical ozone loss rate was relatively fast in the lower stratosphere in the region of frequent PSCs and higher levels of ClO and BrO. The observed PSCs in the vicinity of the minihole supports the model-predicted location of PSCs and chlorine activation. However, ozone miniholes have been attributed almost entirely to dynamical effects due to its short duration. 相似文献
12.
Greco G Madio A Buonavoglia D Totaro M Corrente M Martella V Buonavoglia C 《Veterinary journal (London, England : 1997)》2005,170(3):65-350
A study was carried out in the South of Italy to assess the role of clostridia in neonatal diseases of lambs and kids. Eighty-seven lambs and 15 kids belonging to 25 flocks were examined and Clostridium perfringens was the microorganism most commonly identified. C. perfringens isolates were analysed by polymerase chain reaction (PCR), in order to determine the prevalence of the genes cpa, cpb, cpb2, etx, iap and cpe. The most prevalent toxin-type of C. perfringens was found to be type A found in 84% of the cases with clostridial enterotoxaemia. No C. perfringens type B, C or E were found. C. perfringens type D was isolated in 16% of the cases. About 24% of the isolates were cpb2 positive. The prevalence of cpb2 across the different C. perfringens types varied. The beta(2)-toxin gene cpb2 was detected in 4/21 (19%) type A isolates, in 1/2 type D isolates, and in 1/2 type DE (cpe-carrying type D) isolates. The high rate of positivity to cpb2 among the isolates suggests that a vaccine based on the beta(2)-toxin, should be included in the vaccination schedule of the animals to confer adequate protection and to prevent the disease. 相似文献
13.
One hundred years ago a small group of psychiatrists described the abnormal protein deposits in the brain that define the most common neurodegenerative diseases. Over the past 25 years, it has become clear that the proteins forming the deposits are central to the disease process. Amyloid-beta and tau make up the plaques and tangles of Alzheimer's disease, where these normally soluble proteins assemble into amyloid-like filaments. Tau inclusions are also found in a number of related disorders. Genetic studies have shown that dysfunction of amyloid-beta or tau is sufficient to cause dementia. The ongoing molecular dissection of the neurodegenerative pathways is expected to lead to a true understanding of disease pathogenesis. 相似文献
14.
Moreno A Chiapponi C Boniotti MB Sozzi E Foni E Barbieri I Zanoni MG Faccini S Lelli D Cordioli P 《Veterinary microbiology》2012,156(3-4):265-276
Three subtypes (H1N1, H1N2, and H3N2) are currently diffused worldwide in pigs. The H1N2 subtype was detected for the first time in Italian pigs in 1998. To investigate the genetic characteristics and the molecular evolution of this subtype in Italy, we conducted a phylogenetic analysis of whole genome sequences of 26 strains isolated from 1998 to 2010. Phylogenetic analysis of HA and NA genes showed differences between the older (1998-2003) and the more recent strains (2003-2010). The older isolates were closely related to the established European H1N2 lineage, whereas the more recent isolates possessed a different NA deriving from recent human H3N2 viruses. Two other reassortant H1N2 strains have been detected: A/sw/It/22530/02 has the HA gene that is closely related to H1N1 viruses; A/sw/It/58769/10 is an uncommon strain with an HA that is closely related to H1N1 and an NA similar to H3N2 SIVs. Amino acid analysis revealed interesting features: a deletion of two amino acids (146-147) in the HA gene of the recent isolates and two strains isolated in 1998; the presence of the uncommon aa change (N66S), in the PB1-F2 protein in strains isolated from 2009 to 2010, which is said to have contributed to the increased virulence. These results demonstrate the importance of pigs as mixing vessels for animal and human influenza and show the presence and establishment of reassortant strains involving human viruses in pigs in Italy. These findings also highlighted different genomic characteristics of the NA gene the recent Italian strains compared to circulating European viruses. 相似文献
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17.
Luigi Pane Elisabetta Giacco Christian Corrà Giuliano Greco Gian Luigi Mariottini Franco Varisco Marco Faimali 《Journal of Soils and Sediments》2008,8(2):74-79
Background, Aim and Scope The toxicity of contaminated sediments should be evaluated considering the direct exposure of laboratory organisms to whole
sediments and the indirect exposure to elutriates or extracts (Tay et al. 1992, Byrne and Halloran 1999, Nendza 2002). The
alga Dunaliella tertiolecta is indicated for the use in toxicity bioassays because it is highly sensitive to several xenobiotics. Harpacticoid copepods
have been already used for toxicity testing and Tigriopus fulvus is a promising Mediterranean target-species in ecotoxicology (Todaro et al. 2001, Faraponova et al. 2003, Pane et al. 2005a).
In this study, the toxicity of sediments collected in harbour sites of the Northeastern Adriatic Sea was evaluated by growth
inhibition test with free living and alginate-immobilized Dunaliella tertiolecta and acute toxicity test with nauplii and adult Tigriopus fulvus with the aim of pointing out the importance to utilize model organisms from different trophic levels in sediment ecotoxicology.
Methodology Elutriates and whole sediments were tested on free living and immobilized (Pane et al. 1998) algal cells, and on laboratory
reared copepods. Free-living D. tertiolecta were exposed to diluted elutriates in a static, multi-well plate system. Naalginate immobilized D. tertiolecta were placed in polystyrene inserts fitted with polyester mesh bottoms and exposed to a thin layer (2 mm) of whole sediments
in multi-well plates (EPS 1992, Pane and Bertino 1999). Toxicity tests with copepods were carried out on Tigriopus fulvus nauplii (elutriates) and adults (whole sediments and elutriates). Same-aged nauplii useful for toxicity tests were obtained
by egg sac detaching and consequent hatching stimulation (Pane et al. 2006). Newborn nauplii (I–II stage) were exposed to
elutriates in multi-well plates provided with polystyrene inserts. Adult T. fulvus maintained in polystyrene inserts fitted with polyester mesh bottoms were placed in contact with a thin layer (2 mm) of whole
sediment placed on multi-well plate bottoms. All end-points were evaluated after 96 h.
Results In general, the effects increased with the increasing of elutriate concentration up to 50%; the stimulation or inhibition
of algal growth was statistically significant in comparison to the control. The inhibiting elutriates induced EC50 variations of algal growth ranging from 66.9% to 74.3%. The mortality of T. fulvus nauplii was always < 25% after treatment with 100% elutriates and < 10% after treatment with 50% dilution; no effect was
shown up with 25% dilution; therefore LC50 was not calculable. The effect of elutriates was negligible on adult copepods and LC50 values were never calculable; percent mortality always resulted in < 10% after treatment with whole sediments.
Discussion Both experimental systems gave substantially similar results after exposition to whole sediments and elutriates. During the
experiment with algal cells, the immobilization in Na-alginate and the employment of inserts which allowed the contact of
organisms with sediments and their easy counting were particularly useful. Likewise, the employment of inserts of adequate
mesh size in the tests with copepods allowed the contact of organisms with the sediment and made organism handling and counting
easy, as well as the evaluation of mortality. The methodology here described and the utilization of the proposed test-species
could have an importance also considering that the current trend in ecotoxicological research is towards finding the most
appropriate organism for specific areas of concern by using indigenous species (Mariani et al. 2006) and towards the major
significance of chronic and reproductive end-points.
Conclusions Based on the above results, it can be stated that the bioassay with Dunaliella tertiolecta could be a good estimation tool for the ecotoxicological assessment of marine sediments. The immobilization of algae in Na-alginate
was seen to be useful to evaluate the toxicity of whole sediments; the employment of polystyrene inserts allowed an improvement
of the procedures. T. fulvus nauplii and adults, as other harpacticoids such as Tigriopus japonicus (Yoon et al. 2006), satisfy the basic criteria for the employment of a standard species in marine bioassays. To date only
pelagic Acartia tonsa are utilized in the standardized procedure to evaluate the risk assessment of chemicals or wastewaters (ISO 1999). As, on
the contrary, the exposure of copepods to solid-phase contaminants it is not yet standardized, the employment of polystyrene
inserts improved the procedures for T. fulvus too. So, the rapidity and the possibility to solve practical problems could be the main attractive features of this technique
(Pane et al. 2005a) when applied to whole sediments.
Recommendations and Perspectives The methodology here developed being also applicable to long term and reproduction tests should be recommended because it
provides relevant information in comparison with other frequently applied, standardized biotests with crustaceans (ISO 1999).
The procedure has been shown to be easily applicable to selected marine organisms.
ESS-Submission Editor: Prof. Dr. Henner Hollert (henner.hollert@bio5.rwth-aachen.de) 相似文献
18.
Post‐hatching development of the ornamental ‘Red Cherry Shrimp’ Neocaridina davidi (Bouvier, 1904) (Crustacea,Caridea, Atyidae) under laboratorial conditions
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João A F Pantaleão Rafael A Gregati Rogério C da Costa Laura S López‐Greco Maria L Negreiros‐Fransozo 《Aquaculture Research》2017,48(2):553-569
The ‘Red Cherry shrimp’, Neocaridina davidi is a small freshwater caridean shrimp living, originally, in various kinds of inland water bodies around Asian countries. This shrimp has reached several countries for ornamental use; however, basic information on the biology of the species is still scarce in the literature. Its early post embryonic development morphology has not yet been described. This paper focused on the production and the development of early post‐hatching stages of N. davidi, its male secondary sexual features, observation of the gonads and the presence of females with embryos. The larval development of N. davidi was almost suppressed as noted by the presence of relatively large‐sized eggs, first stage hatching as a decapodid; and the tail fans were present only from the 2nd post‐hatching stage. A biological important consequence of the presence of this Red Cherry shrimp species in the Neotropics is its potential release into nature, which could cause its rapid dispersion affecting populations of other indigenous caridean freshwater shrimps. 相似文献
19.
Maria Grazia Pennino Raul Vilela Jose M. Bellido Francisco Velasco 《Fisheries Oceanography》2019,28(1):54-65
One of the fundamental aims of the Ecosystem Approach to Fisheries Management is to ensure the long‐term sustainability of the fishery by protecting key life‐cycle habitats, such as recruitment areas. In this study, we apply a hurdle Bayesian hierarchical spatio‐temporal model that describes the abundance of European hake (Merluccius merluccius) recruits in the northern continental shelf of the Iberian Peninsula. Our findings clearly show four persistent nurseries, the main one being located along the continental shelf of the Artabrian gulf (off La Coruña). The preferential habitats identified for the hake recruits are areas within a bathymetric range of 120–200 m, with 15–16°C of Sea Surface Temperature, a Chl‐a concentration of 0.8–1.2 mg/m3 and low values of seabed rugosity (unconsolidated substrates). Searching for a compromise with fisheries, we also assess the degree of overlap of the main nursery areas with two fisheries footprints, a local one using Vessel Monitoring System data of trawl fishery of Marín, and a global one using Automatic Identification System data of different type of trawlers (bottom otter, beam and midwater trawls). The two fisheries footprints present different degree of overlapping in distinct areas, highlight the need of specific fleet‐adapted management rules in order to protect juvenile stages. We discuss that understanding the distributional patterns associated with key life stages, such as recruitment, and their interaction with fishing activities, is essential for applying appropriate spatial management measures and improving fishery sustainability. 相似文献
20.
Maternal colouration based on carotenoids has been proposed to negatively affect offspring quality in several taxa, since females might trade off their limited carotenoid resources between body colouration and eggs. This study investigated in the ornamental “red cherry” shrimp (Neocaridina davidi) the relationship between maternal colouration and female reproductive performance, as well as offspring quality. Females selected displayed a broad array of body colour, from less coloured to intensely red coloured and were paired with transparent males. The first two spawning events of each female were studied and compared. The number of newly hatched juveniles was associated to maternal weight, but not to maternal colouration. Offspring quality was measured in terms of survival at the end of the 90‐day growth period, weight and length increment for 0–30 days and 30–60 days periods, and protein, lipid and glycogen contents in 30‐day‐old offspring. Yet, neither of these variables was associated to maternal colouration. These results indicate that there is no trade‐off between maternal colouration and offspring quality in this species. Furthermore, no association was found between maternal and offspring colouration, evaluated at a similar age. However, body colouration in 180‐day old females was significantly higher than in 90‐day‐old females, indicating that female colouration is strongly influenced by age. 相似文献