39,760 research outputs found
A laboratory approach for future exploitation of woody plants in the phytoremediation of antibacterials. Oral presentation
No full textAbstract: Actual veterinary practices are one of the major means through which antibiotics enter the environment. In fact, these
medicines, both used to treat animal diseases and to promote a faster biomass growth, are slowly absorbed by cattle and
the non-absorbed portion is eliminated unchanged in the excreta. As a consequence of manure application to arable
lands followed by leaching processes, surface and ground waters result frequently polluted by a large variety of
antibiotics. Several authors have raised concerns about the potential risks due to environmental presence of these drugs,
such as the spread of medicine resistance among pathogenic bacteria. In opposite to numerous organic compounds (i.e.
petroleum derivates, chlorinated substances, explosives etc.), little is known about the ability of woody plants to remove
these contaminants from the environment. With the aim to investigate the application of phytoremediation technology
to sulfonamides (SAs), one class of the most exploited veterinary medicines, we performed studies with Salix fragilis L.
plants. Willow aptitude to remediate sulfadimethoxine (SDM) was evaluated by studying its ability to both absorb and
tolerate doses of SDM found in soils and surface/ground waters.
Genetically identical Salix fragilis L. cuttings (20-cm long and 1-cm diameter) grown in hydroponic conditions, were
exposed to 0, 0.01, 0.1, 1 and 10 mg L-1
of SDM for one month. The nutrient solution, a 25 times diluted Hoagland’s
nutrient solution, pH 7.0, was entirely replaced twice a week to prevent active molecule and nutrient depletion. During
the experimental period, growth parameters were measured to address the effects of exposure on plant physiology. At
the end of the treatment, plant tissues were analyzed for their SDM and glutathione content through HPLC, to check
both antibiotic accumulation and SDM-induced oxidative stress. Finally, observed alterations in root morphology of
treated plants were studied through light microscopy and further investigated by comparing roots alterations following
both SDM and 3-indoleacetic acid exposure.
Results showed that biometric data didn’t revealed alterations on leaf and stem length, while a hormetic effect on root
length and weight was noticed. In fact, the antibiotic was found to stimulate the root development with 0.01 mg L-1
exposure and to inhibit it at
1 and 10 mg L-1
concentrations. Furthermore, at the dose 10 mg L-1
, important root
morphology alterations were noticed: in particular, this treatment was found to promote an abnormal emission of
numerous lateral roots. We hypothesized a growth hormones disturbance as explication of that hypogeal stress. For this
reason, new Salix cuttings were exposed to SDM 10 mg L-1
and 3-indoleacetic acid (from 5 to 10 mg L-1
) separately for
one month. This assay revealed similar morphologic disturbance of hypogeal apparatus between the antibiotic and the
auxin, suggesting strong hormonal disequilibrium due to SDM treatment. In spite of these evidences, root accumulation
potential was quite high at every SDM dose, while the antibiotic was not detectable in leaves. Furthermore, results
obtained after growing Salix with 10 mg L-1
SDM for two weeks at different plant development stages, showed
differences in plants tolerance according to the developmental step.
These results suggest that Salix fragilis L. could be a well exploitable species for phytoremediation purposes for SAs
concentrations often found in agricultural ecosystems. However, more studies are necessary to define the response of
willow in a soil growth medium, in view to applicative purposes. Furthermore, it would be interesting to scrutinize the
answers of different Salix spp. to SDM and other sulfonamides, under laboratory and field conditions
Effects of a partial to full replacement of soybean meal with Arthrospira platensis on apparent nutrient digestibility of diets for growing pigs
No full textThis study evaluated the effects of replacing soybean meal (SBM) with Arthrospira platensis (AP) on nutrient digestibility of diets for growing pigs and provided a preliminary estimation of AP in vivo digestibility and energy content. The digestibility trial involved 88 pigs during the growing phase of a feeding trial. Pigs were divided into four treatments (AP0, AP33, AP66, and AP100) differing in the progressive SBM replacement with a blend composed of AP, sugar beet pulp, wheat meal, L-lysine, and L-tryptophan at 0, 333, 666, and 1000 g/kg, respectively. Feeds were supplemented with silica (10 g/kg) to increase acid insoluble ash (AIA) content, and individual faecal samples were collected after 71 d on feed, when pigs averaged 117 ± 6 kg of BW. Nutrient digestibility was calculated based on changes in AIA concentration from feed to faeces, while AP digestibility was estimated using the difference method. The metabolisable energy (ME) and net energy (NE) contents of AP were derived from its digestible nutrient contents. Replacement of SBM with the AP-based nucleus did not affect growth rate or the apparent digestibility of dry matter (DM) and most nutrients, except for crude protein (CP), which showed a significant decrease (−3.6%) in the AP100. The digestibility coefficients of DM and CP for AP averaged 861 ± 35.5 and 848 ± 11.5 g/kg, respectively, whereas estimated ME and NE contents averaged 16.2 ± 0.573 and 10.3 ± 0.394 MJ/kg DM, respectively. Overall, replacing SBM with AP in growing pig diets appears feasible in terms of nutritional attributes
Rudist lithosomes related to current pathways in Upper Cretaceous, temperate-type, inner shelves: a case study from the Cilento area, southern Italy
No full textShallow-water foramol limestones have been studied from a locality in the southern Apennines in which outcrop conditions show an excellent overview of the lateral and vertical evolution of rudist bodies and allow their geometry and the dynamic aspects to be reconstructed.
The lithofacies suggest open depositional settings characterized by peloidal silty-muddy sediments. Rudists inhabited well-defined sectors of these shelves, giving rise to wide biostromal bodies, and supplied most of the skeletal debris via bioerosion and minor physical breakdown. In particular, the characteristics of rudist lithosomes document the existence of a complex network of channel-like depressions. In such a depositional context, the evolution of rudist lithosomes seems to have been strongly controlled by the hydrodynamic conditions of the environment. The resulting composite rudist assemblages are characterized by individuals quite often found toppled and oriented parallel to bedding, suggesting continuous sediment movement and/or removal between the organisms. The good preservation of the shells and the common articulation of the valves, however, point to an absence of sustained transport but rather a slight sediment destabilization. The gross lenticular geometry of the shell beds could be related to the above-mentioned patterns of weak, maybe channelized, currents and/or pathways. In most cases, lithosomes may be considered as a multistorey growth in channel-like systems in a persistently subtidal setting.
The depositional setting may be considered as a low-energy system with low tidal range, such that facies transition is very gradual and facies belts are broad, while distinct shoal/barrier deposits are absent. Such a depositional system implies a very low bathymetric slope on which wave energy was minimal, dampened by friction along a broad expanse of shallow water hundreds of kilometres wide. The resulting sea bottoms, dominated by biogenic carbonate sedimentation, were separated by troughs and/or tidal passes.
In such a depositional context, rudist colonization on channel margins assumes particular importance as it documents the rudist ability to exploit a wide array of environments, comparable to that of oysters in Recent seas, and reflecting the probable opportunistic nature of rudists
From artificial engineered materials to metamaterials: 10th anniversary of the Rome workshops on "Metamaterials and Special Materials for Electromagnetic Applications and TLC"
No full textMetamaterials Congress was initiated in 2007 by the FP6 Network of Excellence Metamorphose as the fusion between the series of conferences Bianisotropics and the series of the international workshops Metamaterials and Special Materials for Electromagnetic Applications and TLC. This year we celebrate the 20th anniversary of the Bianisotropics (previously called Bi-isotropics) conference and the 10th anniversary of the meta-workshops. In this contribution, we present a brief history of the meta-workshops and how they merged with Bianisotropics to originate the Metamaterials Congress. In particular, by using the paradigmatic example of the artificial chiral materials, we would also like to reflect the status of the research on complex media in the late 90s and in the beginning of the new century, in order to highlight the reasons behind the contemporary origin of the meta-workshops and of the network Metamorphose
α-Defensin point-of-care test for diagnosis of prosthetic joint infections : neglected role of laboratory and clinical pathologists
No full textPeriprosthetic joint infection (PJI) is a serious complication that may occur after native joint replacement leading to a severe health and economic burden. Currently, due to several confounding factors, PJI is difficult to diagnose. Today, a multidisciplinary approach is indispensable to correctly define a periprosthetic joint infection; indeed, tissue histology, microbiology cultures and clinical findings are used together to achieve this goal. Analysis of α-defensin is commonly used for PJI diagnosis, as it allows the rapid detection of α-defensin present in the synovial fluid following a microbial infection. Currently, a point-of-care testing (POCT) assay able to detect the presence of human α-defensins 1-3 in synovial fluid of patients is aimed directly at orthopedic surgeons. However, many orthopedic surgeons lack experience and training in quality laboratory practices, often failing to appreciate the significance of quality control and proper documentation when using POCT assays. To guarantee the highest quality diagnostic services, the α-defensin test should be used together with other biochemical and microbiological criteria commonly used for PJI diagnosis. Additionally, the close cooperation and communication between laboratory, pathologists and physicians is of fundamental importance in the correct diagnosis of PJI
Dark Fermentation of Arundo donax: Characterization of the Anaerobic Microbial Consortium
No full textThe dark fermentation of lignocellulose hydrolysates is a promising process for the production of hydrogen from renewable sources. Nevertheless, hydrogen yields are often lower than those obtained from other carbohydrate sources due to the presence of microbial growth inhibitors in lignocellulose hydrolysates. In this study, a microbial consortium for the production of hydrogen by dark fermentation has been obtained from a wild methanogenic sludge by means of thermal treatments. The consortium has been initially acclimated to a glucose-based medium and then used as inoculum for the fermentation of Arundo donax hydrolysates. Hydrogen yields obtained from fermentation of A. donax hydrolysates were lower than those obtained from glucose fermentation using the same inoculum (0.30 ± 0.05 versus 1.11 ± 0.06 mol of H2 per mol of glucose equivalents). The hydrogen-producing bacteria belonged mainly to the Enterobacteriaceae family in cultures growing on glucose and to Clostridium in those growing on A. donax hydrolysate. In the latter cultures, Lactobacillus outcompeted Enterobacteriaceae, although Clostridium also increased. Lactobacillus outgrowth could account for the lower yields observed in cultures growing on A. donax hydrolysate. © 2023 by the authors
Arundo donax hydrolysates shape hydrogen-producing microbial community in dark fermentation processs
No full textDark fermentation (DF) has great potential for development as a sustainable biohydrogen production system. Mixed anaerobic microbial consortia from sewage or wastewater sludge digester can be used as seeding for fermentative hydrogen (H2) production. Biomass such as energy crops are good substrates for H2 fermentation. Arundo donax (L.), a perennial non-food crop with high biomass, was chosen as a source of lignocellulosic biomass in a pilot-scale DF process. A mixed microbial consortium from a primary sludge digester, adapted to a synthetic medium amended with glucose, was used as inoculum. Before starting the hydrolysates fermentation, the inoculum was acclimated either on glucose or on A. donax hydrolysates. A glucose fermentation with glucose-acclimated inoculum was used as control. The microbial communities were characterized by Pyrotag sequencing of 16S rRNA genes. Hydrogen producing populations were quantified by Real-Time PCR of specific 16S rRNA and hydrogenase genes. Other coexisting microorganisms were also quantified. Performances of A. donax fermentation in presence of differently acclimated consortia were compared by analyzing molecular data in conjunction to H2 production. In glucose fermentation, where H2 production was fast, the bacterial consortium was characterized by the co-dominance of Enterobacteriaceae and Lactobacillaceae being 80% and 15% of the total community respectively. Microbial communities of both A. donax fermentations strongly differed from those of glucose-fermentation, being characterized by the dominance of Lactobacillaceae (40% of the total) and low percentages of H2 producing populations (<0.5% of the total). Quantification of hydrogenase genes of Clostridium spp. confirmed that these populations were present in low amount (104 gene copies). Nevertheless, remarkable H2 yields were recorded. The study evidence that the inhibitory compounds derived from the hydrolysis of A. donax had a prompt effect on the microbial community of the inoculum. However, this noticeable shift in the microbial communities did not affect H2 production. Finally, adaptation on different carbon substrates exerted a comparable selective pressure, leading to similar H2 yields
Comparison of carbon balance in Mediterranean pilot constructed wetlands vegetated with different C4 plant species
No full textThis study investigates carbon dioxide (CO2) and methane (CH4) emissions and carbon (C) budgets in a horizontal subsurface flow pilot-plant constructed wetland (CW) with beds vegetated with Cyperus papyrus L., Chrysopogon zizanioides (L.) Roberty, and Mischantus × giganteus Greef et Deu in the Mediterranean basin (Sicily) during the 1st year of plant growing season. At the end of the vegetative season, M. giganteus showed the higher biomass accumulation (7.4 kg m−2) followed by C. zizanioides (5.3 kg m−2) and C. papyrus (1.8 kg m−2). Significantly higher emissions of CO2 were detected in the summer, while CH4 emissions were maximum during spring. Cumulative CO2 emissions by C. papyrus and C. zizanioides during the monitoring period showed similar trends with final values of about 775 and 1,074 g m−2, respectively, whereas M. giganteus emitted 3,395 g m−2. Cumulative CH4 bed emission showed different trends for the three C4 plant species in which total gas release during the study period was for C. papyrus 12.0 g m−2 and ten times higher for M. giganteus, while C. zizanioides bed showed the greatest CH4 cumulative emission with 240.3 g m−2. The wastewater organic carbon abatement determined different C flux in the atmosphere. Gas fluxes were influenced both by plant species and monitored months with an average C-emitted-to-C-removed ratio for C. zizanioides, C. papyrus, and M. giganteus of 0.3, 0.5, and 0.9, respectively. The growing season C balances were positive for all vegetated beds with the highest C sequestered in the bed with M. giganteus (4.26 kg m−2) followed by C. zizanioides (3.78 kg m−2) and C. papyrus (1.89 kg m−2). To our knowledge, this is the first paper that presents preliminary results on CO2 and CH4 emissions from CWs vegetated with C4 plant species in Mediterranean basin during vegetative growth
MotoCell, a modular web application for studying cell movement
No full textEvaluation of motility of transformed cell lines in different experimental conditions with MotoCell
Rossella Tufano1, E. Toscano1, L.Sepe1,2, G. Paolella1,2
1Dept Molecular Medicine and Medical Biotechnology, Federico II Univ., Naples, Italy 2CEINGE Advanced Biotechnologies, Naples, Italy
Cell migration, the process by which cells or cell groups move from one location to another, plays a crucial role in different physiological and pathological conditions and may be easily observed in cultured cells as well as in vivo.
Cell migration studies imply an acquisition phase by time-lapse microscopy, followed by cell tracking and statistical analysis. MotoCell is a tool for quantitative study of cell movement, developed in our laboratory where it is continuously extended and improved. It is an environment where cell tracking, evaluation of motility parameters and statistical analysis is fully integrated, to effectively study motility of cell populations as well as the behaviour of single individual cells, maintained in different experimental conditions. Many analysis procedures use the analytical tools and graphical representations available in R, which is transparently accessed within the analysis section and provides sophisticated statistical analysis tools. All these aspects are integrated in a web application, which may be conveniently, quickly and interactively used from the operator desktop without requiring any installation step. MotoCell may be used to identify and study homogeneous subgroups in heterogenous populations by selecting movement data on the basis of the features of the observed cells
ErlangTW: a Time Warp simulator written in Erlang
No full textErlangTW is a parallel/distributed simulation middleware based on the Time Warp synchronization protocol. ErlangTW is entirely written in Erlang, a concurrent, functional programming language specifically targeted at building distributed systems. We argue that writing parallel simulation models in Erlang is considerably easier than using conventional programming languages. Moreover, ErlangTW allows simulation models to be executed either on single-core, multicore and distributed computing architectures.
We have developed a complete implementation of Time Warp and to evaluate the performance of ErlangTW we used a synthetic benchmark called PHOLD, that is a model specifically designed for the performance evaluation of Time Warp implementations.
Both ErlangTW and the PHOLD model are provided in source code with an open source license
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