A check on the efficiency of an air-bubble screen using acoustic measurements and an artificial tracer     

Laura Cutroneo  Fokko van der Goot  Alexis Roels  Michela Castellano  Max Radermacher  Sergio Tucci  Paolo Povero  Giuseppe Canepa  Marco Capello 《Journal of Soils and Sediments》2014,14(9):1626-1637

Purpose

A working group, composed of the University of Genoa (Italy), responsible for monitoring the dredging of the Port of Genoa, and Royal Boskalis Westminster N.V. (The Netherlands), responsible for the dredging activities, carried out an experiment on closing a landfill area with a double air bubble-screen (ABS) to verify the efficiency both of this method of containing sediment and of the measurement method applied.

Materials and methods

Within the Port of Genoa dredging, which was started in 2009, the dredged material is used to fill two areas between existing quays. To contain the sediment to be placed into a third subbasin without interrupting the passage of the barges which discharge the sediment, the use of an ABS was proposed as a barrier to the spreading of the sediment. The experiment was carried out during a 4-day oceanographic campaign to verify, preliminarily, the results under different weather and sea conditions. An artificial tracer, rhodamine water tracing (RWT), was used in varying concentrations to simulate the spreading of the sediment, and an RWT sensor and an acoustic Doppler current profiler (ADCP) were used to measure the RWT distribution and verify the efficiency of the ABS.

Results and discussion

The high turbidity in the port and the high rate of RWT dilution made it relatively difficult to detect the RWT. The RWT sensor sometimes measured higher values than expected probably due to the following: the recirculation of the tracer in current eddies, other sensible suspended matter and adsorption of RWT on suspended matter. The internal ABS could not retain all the RWT, possibly because it was much weaker than the external one, and because mitigating measures, like silt screens or ABSs, are not totally closed and should not be used if complete impermeability is required. The ABS introduction accentuated the natural separation between the basin and the channel water bodies creating a barrier between the two basins.

Conclusions

An ABS installed at the entrance to a confined area with low dynamics results in a circular vertical flow with the potential to retain suspended sediments within an enclosed area. The meteorological variability during the tests showed that a weak ABS could malfunction in the presence of strong wind condition. The results showed that the ADCP is a suitable instrument to highlight the ABS position and its effect on the surrounding hydrodynamics. Further research, using a sediment tracer, is required to study with greater detail the effects of the ABS on the water column.  相似文献   

Degradation studies on benzoxazinoids. Soil degradation dynamics of 2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (DIMBOA) and its degradation products, phytotoxic allelochemicals from gramineae     

Macías FA  Oliveros-Bastidas A  Marín D  Castellano D  Simonet AM  Molinillo JM 《Journal of agricultural and food chemistry》2004,52(21):6402-6413

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Modeling flavor release using inverse gas chromatography-mass spectrometry   总被引：2，自引：0，他引：2  

Castellano J  Snow NH 《Journal of agricultural and food chemistry》2001,49(9):4296-4299

Inverse gas chromatography (IGC)-mass spectrometry was used to determine the extent of flavor release from a food matrix as a function of moisture uptake. At the surface of a solid, components with higher binding affinities can exchange with and replace components with lower binding affinities. As a low moisture baked product absorbs moisture from the air, flavor is lost from the matrix as water molecules exchange with the flavor molecules. The amount of flavor lost over time can be modeled using this approach to determine the onset of flavor release and total amount of flavor release as well as the identity of the released components and their relative order of exclusion from the matrix.  相似文献   

Normal Phagocytic Capacity of Macrophages Isolated from Different Canine Organs     

Enrique Leo  Portiansky María Cecilia  Castellano 《Anatomia, histologia, embryologia》1989,18(3):199-204

Conventional methods used in laboratory animals for collection of resident macrophages (MAC) proved suitable for isolation of hepatic, splenic, dermic, peritoneal and alveolar MAC of healthy dogs. Phagocytic assays of IgG opsonised SRBC were performed with resident MAC obtained from these organs. Results showed the existence of statistically significant differences among phagocytic capacity of the investigated MAC. According to this, three groups of MAC could be defined: a first group comprising dermic, splenic and alveolar MAC; a second group comprising hepatic MAC and a third group comprising peritoneal MAC.  相似文献   

Identification of NOx and Ozone Episodes and Estimation of Ozone by Statistical Analysis     

María Castellano  Amaya Franco  David Cartelle  Manuel Febrero  Enrique Roca 《Water, air, and soil pollution》2009,198(1-4):95-110

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Evaluation of Body Weight,Body Condition,and Muscle Condition in Cats with Hyperthyroidism          下载免费PDF全文

M.E. Peterson  C.A. Castellano  M. Rishniw 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2016,30(6):1780-1789

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Potential Biomedical Applications of Collagen Filaments derived from the Marine Demosponges Ircinia oros (Schmidt, 1864) and Sarcotragus foetidus (Schmidt, 1862)     

Marina Pozzolini  Eleonora Tassara  Andrea Dodero  Maila Castellano  Silvia Vicini  Sara Ferrando  Stefano Aicardi  Dario Cavallo  Marco Bertolino  Iaroslav Petrenko  Hermann Ehrlich  Marco Giovine 《Marine drugs》2021,19(10)

Collagen filaments derived from the two marine demosponges Ircinia oros and Sarcotragus foetidus were for the first time isolated, biochemically characterised and tested for their potential use in regenerative medicine. SDS-PAGE of isolated filaments revealed a main collagen subunit band of 130 kDa in both of the samples under study. DSC analysis on 2D membranes produced with collagenous sponge filaments showed higher thermal stability than commercial mammalian-derived collagen membranes. Dynamic mechanical and thermal analysis attested that the membranes obtained from filaments of S. foetidus were more resistant and stable at the rising temperature, compared to the ones derived from filaments of I. oros. Moreover, the former has higher stability in saline and in collagenase solutions and evident antioxidant activity. Conversely, their water binding capacity results were lower than that of membranes obtained from I. oros. Adhesion and proliferation tests using L929 fibroblasts and HaCaT keratinocytes resulted in a remarkable biocompatibility of both developed membrane models, and gene expression analysis showed an evident up-regulation of ECM-related genes. Finally, membranes from I. oros significantly increased type I collagen gene expression and its release in the culture medium. The findings here reported strongly suggest the biotechnological potential of these collagenous structures of poriferan origin as scaffolds for wound healing.  相似文献   

Structure-activity relationship (SAR) studies of benzoxazinones, their degradation products, and analogues. Phytotoxicity on problematic weeds Avena fatua L. and Lolium rigidum Gaud     

Macías FA  Marín D  Oliveros-Bastidas A  Castellano D  Simonet AM  Molinillo JM 《Journal of agricultural and food chemistry》2006,54(4):1040-1048

Avena fatua L. (wild oat) and Lolium rigidum Gaud. (rigid ryegrass) are highly problematic weeds affecting a wide variety of cereal crops worldwide. The fact that both of these weeds have developed resistance to several herbicide groups made them optimal candidates as target organisms for ongoing research about the potential application of allelochemicals and analogue compounds as natural herbicide models. Benzoxazinones, a family of natural allelochemicals present in corn, wheat, and rye, including 2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4H)-one and 2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one, together with some degradation products, found in crop soils as well as in other systems, and some synthetic analogues of them were tested on wild oat and rigid ryegrass seeds; the results were statistically treated, and some structure-activity relationships, useful in further development of natural herbicide models, were elucidated. The most active compounds were the synthetic benzoxazinone 2-acetoxy-(2H)-1,4-benzoxazin-3(4H)-one and the degradation product 2-aminophenoxazin-3-one, with highly significant inhibition on the development of both weeds. The ecological role of these compounds is discussed by considering both degradability and phytotoxicity. The bioactivity of aminophenoxazines has been correlated by their aqueous solubility-lipophilicity predicted by means of computational methods.  相似文献   

Structure-Activity Relationships (SAR) studies of benzoxazinones, their degradation products and analogues. phytotoxicity on standard target species (STS)   总被引：3，自引：0，他引：3  

Macías FA  Marín D  Oliveros-Bastidas A  Castellano D  Simonet AM  Molinillo JM 《Journal of agricultural and food chemistry》2005,53(3):538-548

Benzoxazinones 2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (DIMBOA) and 2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4H)-one (DIBOA) have been considered key compounds for understanding allelopathic phenomena in Gramineae crop plants such as corn (Zea mays L.), wheat (Triticum aestivum L.), and rye (Secale cereale L.). The degradation processes in the environment observed for these compounds, in which soil microbes are directly involved, could affect potential allelopathic activity of these plants. We present in this work a complete structure-activity relationships study based on the phytotoxic effects observed for DIMBOA, DIBOA, and their main degradation products, in addition to several synthetic analogues of them. Their effects were evaluated on standard target species (STS), which include Triticum aestivum L. (wheat) and Allium cepa L. (onion) as monocots and Lepidium sativum L. (cress), Lactuca sativa L. (lettuce), and Lycopersicon esculentum Will. (tomato) as dicots. This permitted us to elucidate their ecological role and to propose new herbicide models based on their structures. The best phytotoxicity results were shown by the degradation chemical 2-aminophenoxazin-3-one (APO) and several 2-deoxy derivatives of natural benzoxazinones, including 4-acetoxy-(2H)-1,4-benzoxazin-3(4H)-one (ABOA), 4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one (D-DIBOA), and 4-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (D-DIMBOA). They showed high inhibitory activity over almost all species growth. The fact that APO is a degradation product from DIBOA with high phytotoxicity and stability makes it possible to assign an important ecological role regarding plant defense mechanisms. 2-Deoxy derivatives of natural benzoxazinones display a wide range of activities that allow proposing them as new leads for natural herbicide models with a 1,4-benzoxazine skeleton.  相似文献   

Particle Phase Concentrations of Polycyclic Aromatic Hydrocarbons in the Atmospheric Environment of Jinámar,Gran Canaria     

López Cancio  José A.  Castellano  Antonio Vera  Trujillo  Rosa Navarro  Jiménez  José Corujo 《Water, air, and soil pollution》2002,136(1-4):93-113

Airborne concentrations of 8 polycyclic aromatic hydrocarbons (PAHs): fluoranthene, Flt, Pyrene, Pyr, benzo(a)anthracene, BaA, chrysene, Chr, benzo(b)fluoranthene + benzo(k)fluoranthene,B(b + k)F, benzo(a)pyrene, BaP and benzo(g,h,i)perylene, B(ghi)P,were measured in Jinámar, a small town on the island of Gran Canaria (Spain) during a 12 month period (January 1995–December 1995). Concentrations ranged between 0.613 ng m^-3 for B(ghi)P and 0.040 and 0.046 ng m^-3 for pyrene and chrysene. Except for BaA all PAHs occurred at lower concentrations at temperatures below 20 °C. Relative humidity seems to influence concentrations of pyrene, chrysene, benzo(b + k)fluoranthene and benzo(a)pyrene, also affecting the latter ina different way to the other three hydrocarbons cited.  相似文献