324 research outputs found

    Modeling Posidonia oceanica shoot density and rhizome primary production

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    Posidonia oceanicameadows rank among the most important and most productive ecosystems in the Mediterranean basin, due to their ecological role and to the goods and services they provide. estimations of crucial ecological process such as meadows productivity could play a major role in an environmental management perspective and in the assessment of P. oceanicaecosystem services. In this study, a Machine Learning approach, i.e. Random Forest, was aimed at modeling P. oceanica shoot density and rhizome primary production using as predictive variables only environmental factors retrieved from indirect measurements, such as maps. Our predictive models showed a good level of accuracy in modeling both shoot density and rhizome productivity (R 2 = 0.761 and R 2 = 0.736, respectively). Furthermore, as shoot density is an essential parameter in the estimation of P. oceanica productivity, we proposed a cascaded approach aimed at estimating the latter using predicted values of shoot density rather than observed measurements. In spite of the complexity of the problem, the cascaded Random forest performed quite well (R2 = 0.637). While direct measurements will always play a fundamental role, our estimates could support large scale assessment of the expected condition of P. oceanica meadows, providing valuable information about the way this crucial ecosystem works

    Consecutive episodes of heart and kidney failure in an "otherwise" healthy young man

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    Background: Acute renal failure is a rare occurrence in a patient with an unremarkable past medical history and should always lead to an in depth clinical study. The occurrence in the same healthy young subject, of consecutive episodes of heart failure and of acute renal failure is an even rarer event and should prompt diagnostic tests and restrict the diagnostic hypotheses. Case presentation: We present the case of a 28 year-old man who, while waiting to undergo assessment for a mild chronic kidney disease, was diagnosed with decompensated dilated cardiomyopathy and placed on diuretics and β-blockers. After few weeks he developed a non oligoanuric acute renal failure with a slight elevation of serum calcium. Renal biopsy proved suggestive for renal sarcoidosis; thus the hypothesis of systemic sarcoidosis with cardiac and renal involvement was possible avoiding further delay in initiation of therapy. Conclusions: Cardiac sarcoidosis is usually silent but the majority of cases are diagnosed when cardiac symptoms are present in a patient with systemic sarcoidosis. Renal involvement with granulomatous interstitial nephritis is also quite rare and can be an unexpected finding at kidney biopsy. This case highlights the need to evaluate thoroughly clinical problems that do not fit in a specific scenario and emphasizes the importance of performing a kidney biopsy in case of kidney failure of unknown etiology

    Easy preparation of liposome@pda microspheres for fast and highly efficient removal of methylene blue from water

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    Mussel-inspired chemistry was usefully exploited here with the aim of developing a high-efficiency, environmentally friendly material for water remediation. A micro-structured material based on polydopamine (PDA) was obtained by using liposomes as templating agents and was used for the first time as an adsorbent material for the removal of methylene blue (MB) dye from aqueous solutions. Phospholipid liposomes were made by extrusion and coated with PDA by self-polymerization of dopamine under simple and mild conditions. The obtained Liposome@PDA microspheres were characterized by DLS and Zeta potential analysis, TEM microscopy, and FTIR spectroscopy. The effects of pH, temperature, MB concentration, amount of Liposome@PDA, and contact time on the adsorption process were investigated. Results showed that the highest adsorption capacity was obtained in weakly alkaline conditions (pH = 8.0) and that it could reach up to 395.4 mg g−1 at 298 K. In addition, adsorption kinetics showed that the adsorption behavior fits a pseudo-second-order kinetic model well. The equilibrium adsorption data, instead, were well described by Langmuir isotherm. Thermodynamic analysis demonstrated that the adsorption process was endothermic and spontaneous (∆G0 = −12.55 kJ mol−1, ∆H0 = 13.37 kJ mol−1 ) in the investigated experimental conditions. Finally, the applicability of Liposome@PDA microspheres to model wastewater and the excellent reusability after regeneration by removing MB were demonstrated

    Results of patch-grafting of tissue infected by ‘Candidatus Phytoplasma pyri’ or by ‘Candidatus Phytoplasma prunorum’, respectively on pear and apricot plants cultivated in pot

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    Molecular analyses carried out either on the pear varieties ‘Conference’, ‘Comice’ and ‘William’ grafted on different rootstocks or on sixty-eight apricot varieties grafted on Myrobalan, showed the susceptibility of the tested combinations to 'Candidatus Phytoplasma pyri', transmitted by Cacopsylla pyri, and to 'Candidatus Phytoplasma prunorum', transmitted by Empoasca decedens, respectively. In order to find pear and/or apricot combinations immune to the associated Phytoplasma, several varieties grafted on new rootstock were tested in the period 2002-2008. 68 pear plants belonging to seven variety/rootstock combinations and 76 apricot plants belonging to seven combinations, all cultivated in pot, in greenhouse covered by anti-aphid tissue, were grafted with patches of infected tissues containing the specific phytoplasmas. Young healthy potted plants belonging to the pear combination ‘Comice’/P. communis and to the apricot combination ‘Palummella’/Myrobalan, both susceptible in open field to the associated phytoplasmas transmitted by the specific vectors, were also used and patch-grafted. Molecular analyses, carried out on nucleic acids extracted from leaf samples, to detect the presence of the pathogens, showed the pear variety ‘William’ grafted on Pyrus betulaefolia to be susceptible to 'Candidatus Phytoplasma pyri’. Neither the pear combination ‘Comice’/P. communis nor the apricot ‘Palummella’/Myrobalan 29 C, susceptible, in open field, to the associated phytoplasmas, became infected after patchgrafting under greenhouse conditions. Thus the results show that patch-grafting cannot be utilized in young potted plants for artificial transmission of these two phytoplasmas.Keywords: Phytoplasmas, source of immunity, variety/rootstock combination, molecular tests, insect proof green-hous

    Materia primordiale e Growing Design

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    Il particolare momento di crisi economica che il mondo occidentale sta attraversando, ha generato nel design alcune tendenze “autarchiche” che si sviluppano prevalentemente intorno a materie primordiali, basiche e naturalmente disponibili. Materiali al grado “zero” capaci di crescere, trasformarsi e rigenerarsi anche in vitro; materiali biologici e vivi dalle straordinarie potenzialità espressive e performative; materiali etici, sinceri e democratici perché realizzati con materia edibile o di scarto. E così, sotto il comune denominatore di una estetica del “primitivo” e dell’”imperfetto”, assistiamo ad un processo inversamente proporzionale in cui ad un maggior grado di sofisticazione tecnologica corrisponde paradossalmente un minor livello di ricercatezza estetico-formale.The economic crisis currently sweeping the western world has generated several “autarchic” trends primarily involving primordial, basic and naturally available materials. These “zero” degree materials can grow, transform and regenerate themselves even in vitro. They are live, biological materials with amazing expressive and performance potential, as well as being ethical, genuine and democratic because they are made with edible or waste material. Concealed behind this common denominator of “primitive” and “imperfect” aesthetics is an inversely proportional process; greater technological sophistication paradoxically corresponds to less aesthetic and formal refinement

    Smart Flow for the evaluation of the hemodialysis arteriovenous fistula

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    Background: Smart Flow is an innovative tool available on the Carestream Touch Prime Ultrasound machines, which provides automated blood flow measurement and shows the vectors that form the blood flow in the vessel. We compared the use of Smart Flow with traditional Duplex Doppler Ultrasound to evaluate blood flow of arteriovenous fistulas in prevalent hemodialysis patients. Methods: A total of 31 chronic patients on hemodialysis were enrolled. Blood flow was measured on the brachial artery with Smart Flow and duplex Doppler ultrasound. In a subset of 26 patients, a video of the juxta-anastomotic efferent vein was recorded and analyzed to calculate an index of flow turbulence. Results: We enrolled 21 males and 10 females aged 68.52 ± 11.64 years at the time of evaluation with an average arteriovenous fistulas vintage of 50.23 ± 47.42 months and followed them up for 18.03 ± 5.18 months. Smart Flow and Duplex Doppler Ultrasound blood flow measurements positively correlated (p < 0.0001) in the same patient but Smart Flow gave higher blood flow values (995.0 vs 730.3 mL/min, p < 0.0001), and the Duplex Doppler Ultrasound blood flow standard deviation was similar to Smart Flow (125.4 vs 114.4 mL/min, p < 0.0001). The time needed to evaluate arteriovenous fistulas with Smart Flow was significantly shorter than Duplex Doppler Ultrasound (67.58 ± 19.89 vs 146.3 ± 26.35 s, p < 0.0001). No correlation was found between blood flow turbulence and the subsequent access failure. Conclusion: Smart Flow is reliable, reproducible, and faster than traditional duplex ultrasound. However, the additional information given by the Smart Flow technique does not seem to add any further benefits in terms of prediction of the access failure

    Concerning synthesis of new biobased polycarbonates with curcumin in replacement of bisphenol a and recycled diphenyl carbonate as example of circular economy

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    Curcumin (CM) is a natural polyphenol well-known for its antioxidant and pharmaceutical properties, that can represent a renewable alternative to bisphenol A (BPA) for the synthesis of biobased polycarbonates (PC). In the presented strategy, preparation of the CM-based PC was coupled with chemical recycling of the fossil-based BPA polycarbonate (BPA-PC) conducting a two-steps trans-polymerization that replaces BPA monomer with CM or its tetrahydrogenated colorless product (THCM). In the first step of synthetic strategy, depolymerization of commercial BPA-PC was carried out with phenol as nucleophile, according to our previous procedure based on zinc derivatives and ionic liquids as catalysts, thus producing quantitatively diphenyl carbonate (DPC) e BPA. In the second step, DPC underwent a melt transesterification with CM or THCM monomers affording the corresponding bio-based polycarbonates, CM-PC and THCM-PC, respectively. THCM was prepared by reducing natural bis-phenol with cyclohexene as a hydrogen donor and characterized by 1H-NMR and MS techniques. Polymerization reactions were monitored by infrared spectroscopy and average molecular weights and dispersity of the two biobased polymers THCM-PC and CM-PC were determined by means of gel permeation chromatography (GPC). Optical properties of the prepared polymers were also measured

    Loss of renal function in the elderly italians: a physiologic or pathologic process?

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    Abstract BACKGROUND: Nowadays it seems that chronic kidney disease (CKD) is outbreaking, mostly in the elderly participants. The aim of this study was to assess the progression of CKD in different ages. METHODS: We conducted a monocentric, retrospective, observational study enrolling 116 patients afferent to our outpatient clinic. INCLUSION CRITERIA: age >18 years, follow-up ≥5 years, estimated glomerular filtration rate (eGFR) <60mL/min/1.73 m(2), and/or diagnosed renal disease and/or presence of renal damage. Patients were divided into four groups according to their age: 25-55 years (n = 27), 56-65 (25), 66-75 (42), and 76-87 (22). eGFR was calculated using the modification of diet in renal disease and the CKD-epidemiology collaboration formulas. RESULTS: Younger patients had a significantly longer follow-up and less comorbidities, evaluated by the cumulative illness rating scale score, compared with the other groups. There was no difference between creatinine at baseline and at the end-of-follow-up period among the groups. Even though renal function significantly decreased in all groups, we noticed a slower progression as the age increased, and the difference between basal and end-of-follow-up eGFR was minimal in the group of patients aged 76-87 years. Analyzing the eGFR of every ambulatory control plotted against the year of follow-up, we showed a more rapid loss of filtrate in the younger group. Instead, loss of renal function decreased as the age of patients increased. CONCLUSIONS: This study demonstrates that, in elderly Italian participants, progression of CKD occurs more slowly than in younger patients. This implies that we may probably face an epidemic of CKD but that most of elderly patients diagnosed with CKD may not evolve to end-stage renal disease and require renal replacement therapy

    Lipid-based systems loaded with PbS nanocrystals: near infrared emitting trackable nanovectors

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    Hydrophobic PbS nanocrystals (NCs) emitting in the near infrared spectral region were encapsulated in the core of micelles and in the bilayer of liposomes, respectively, to form polyethylene glycol (PEG)-grafted phospholipids. The phospholipid-based functionalization process of PbS NCs required the replacement of the pristine capping ligand at the NC surface with thiol molecules. The procedures carried out for two systems, micelles and liposomes, using PEG-modified phospholipids were carefully monitored by optical, morphological and structural investigations. The hydrodynamic diameter and the colloidal stability of both micelles and liposomes loaded with PbS NCs were evaluated using Dynamic Light Scattering (DLS) and z-potential experiments, and both were satisfactorily stable in physiological media. The cytotoxicity of the resulting PbS NC-loaded nanovectors was assessed by the in vitro investigation on Saos-2 cells, indicating that the toxicity of the PbS NC loaded liposomes was lower than that of the micelles with the same NC cargo, which is reasonable due to the different overall composition of the two prepared nanocarriers. Finally, the cellular uptake in the Saos-2 cells of both the NC containing systems was evaluated by means of confocal microscopy studies by exploiting a visible fluorescent phospholipid and demonstrating the ability of both luminescent nanovectors to be internalized. The obtained results show the great potential of the prepared emitting nanoprobes for imaging applications in the second biological window
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