13 research outputs found

    Differenziazione e quantificazione dei carbonati litogenici e pedogenici di Gypsisuoli forestali attraverso l'analisi isotopica

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    Gli autori riferiscono sui tipi e sui modelli di genesi dei carbonati dei suoli, attraverso l’uso degli isotopi del 13C. Lo studio è stato condotto in un’area dell’interno collinare argilloso siciliano, su suoli che evolvono sui depositi evaporitici della Serie Gessoso-Solfifera. Sono stati scelti cinque pedon su litotipi calcarei e non. I pedon sono stati descritti in campo e campionati secondo la sequenza degli orizzonti genetici; sui campioni di suolo sono state eseguite le seguenti analisi: tessitura, reazione, conducibilità elettrica, gesso, carbonio organico ed inorganico. Inoltre, parallelamente sono state eseguite le analisi isotopiche del carbonio organico ed inorganico. I risultati hanno consentito di individuare, oltre che le complesse relazioni esistenti tra la componente abiotica e biotica del suolo, anche i modelli di genesi dell’orizzonte calcico e quindi le relative implicazioni sulla classificazione dei pedon investigati

    Diagnostic and prognostic role of myocardial perfusion scintigraphy in kidney transplant candidates: narrative review

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    PurposeCardiac screening in adult kidney transplant candidates with myocardial perfusion scintigraphy (MPS) can reveal findings associated with increased risk for coronary heart disease events, but the exact value of this screening test is still undetermined.MethodsNarrative review based on the available literature and guidelines on the yield, benefits, and harms of MPS screening in kidney transplant candidates.ResultsAlthough coronary angiography carries low risk in general population, it is not without risk particularly in patients with complex comorbid disease and the use of intravenous contrast media may precipitate a need for hospitalization and death. We could avoid invasive coronary angiography in patients with chronic kidney disease, although with high coronary calcium score, but good left ventricle function and normal perfusion, evaluated by Gated single-photon emission computed tomographic (SPECT) MPS. In fact, although Gated SPECT MPS has not a high sensitivity, it provides some variables that are closely related to sudden death: post-stress and rest-ejection fraction and left ventricular volumes, left ventricle muscle mass, extent of ischemia and scar.ConclusionsGated SPECT MPS is a valid noninvasive cardiac screening test. It can be used as alternative to stress echocardiography in kidney transplant candidates with high cardiovascular risk and a positive or inconclusive exercise tolerance ECG test.Patients with abnormal perfusion and cardiac dysfunction should undergo invasive coronary artery imaging and endovascular treatment, while angiography could be avoided in patients with normal MPI, having good long-term prognosis

    Soil physical-mechanical properties evaluation in different tillage systems

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    In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of ro-totilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the Department of Agricultural and Forest Sciences, University of Palermo, in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of three machines for shallow tillage: a chisel plough (CP), a rototilling (RT) and a spading machine (SM) on penetration resistance in semi-arid environments of the Mediterranean basin. No tillage was also included. Penetration resistance (PR) was surveyed for all the treatments to a depth of 300 mm with an electronic dynamometer. The study was carried out in 2011-201. The treatments consisted in the exe-cution of a shallow tillage to a depth of 150 mm. SP treatment allowed us to obtain PR lower values throughout the tillage profile than RT, CP and NT. It follows that the type of machine used influences soil PR, and then the soil water storage capacity, key factor for the agricultural productions in semi-arid environments as in Sicily

    Effect of different soil management in sloping vineyards on soil penetration resistance.

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    In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of rototilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the SAF (Scienze Agrarie e Forestali) Department of the University of Palermo in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of three machines for shallow tillage: a chisel plough (CP), a rototilling (RT) and a spading machine (SM) on penetration resistance in semi-arid environments of the Mediterranean basin. No tillage was also included. Penetration resistance (PR) was surveyed for all the treatments to a depth of 300 mm with an electronic dynamometer. The treatments consisted in the execution of a shallow tillage to a depth of 150 mm. SP treatment allowed us to obtain PR lower values throughout the tillage profile than RT, CP and NT. It follows that the type of machine used influences soil PR, and then the soil water storage capacity, key factor for the agricultural productions in semi-arid environments as in Sicily

    Soil management effect on soil penetration resistance in the vineyard

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    In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of rototilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the SAF (Scienze Agrarie e Forestali) Department of the University of Palermo in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of three machines for shallow tillage: a chisel plough (CP), a rototilling (RT) and a spading machine (SM) on penetration resistance in semi-arid environments of the Mediterranean basin. No tillage was also included. Penetration resistance (PR) was surveyed for all the treatments to a depth of 300 mm with an electronic dynamometer. The treatments consisted in the execution of a shallow tillage to a depth of 150 mm. SP treatment allowed us to obtain PR lower values throughout the tillage profile than RT, CP and NT. It follows that the type of machine used influences soil PR, and then the soil water storage capacity, key factor for the agricultural productions in semi-arid environments as in Sicily

    Influence of Adsorbed Water on the Activation Energy of Model Photocatalytic Reactions

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    Two commercial (Merck and Sigma-Aldrich) and two home prepared (HP05 and HP05C) powdered TiO2 photocatalysts were investigated by fast field cycling nuclear magnetic resonance experiments in order to explore the nature of the interactions between water and the solid surfaces. The results were related to the activation energies determined at temperatures ranging from 303 to 353 K for the photocatalytic oxidation in water of three model molecules presenting different interactions with the solid surface (catechol, phenol, and metylbenzoate). The photoactivity results at different temperatures were comparable to each other because the uns were carried out while keeping constant the concentration of O2 in the suspensions. The study highlights the influence of the adsorbed water on the activation energy of a photocatalytic reaction. In particular, we showed that competition between water and substrate adsorption is a determining factor in the activation energy of a photocatalytic oxidation reaction

    Tolerance, Adaptation, and Cell Response Elicited by Micromonospora sp. Facing Tellurite Toxicity: A Biological and Physical-Chemical Characterization

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    The intense use of tellurium (Te) in industrial applications, along with the improper disposal of Te-derivatives, is causing their accumulation in the environment, where oxyanion tellurite (TeO32−) is the most soluble, bioavailable, and toxic Te-species. On the other hand, tellurium is a rare metalloid element whose natural supply will end shortly with possible economic and technological effects. Thus, Te-containing waste represents the source from which Te should be recycled and recovered. Among the explored strategies, the microbial TeO32− biotransformation into less toxic Te-species is the most appropriate concerning the circular economy. Actinomycetes are ideal candidates in environmental biotechnology. However, their exploration in TeO32− biotransformation is scarce due to limited knowledge regarding oxyanion microbial processing. Here, this gap was filled by investigating the cell tolerance, adaptation, and response to TeO32− of a Micromonospora strain isolated from a metal(loid)-rich environment. To this aim, an integrated biological, physical-chemical, and statistical approach combining physiological and biochemical assays with confocal or scanning electron (SEM) microscopy and Fourier-transform infrared spectroscopy in attenuated total reflectance mode (ATR-FTIR) was designed. Micromonospora cells exposed to TeO32− under different physiological states revealed a series of striking cell responses, such as cell morphology changes, extracellular polymeric substance production, cell membrane damages and modifications, oxidative stress burst, protein aggregation and phosphorylation, and superoxide dismutase induction. These results highlight this Micromonospora strain as an asset for biotechnological purposes

    Preliminary Analysis of Placental Metabolome in Maternal Obesity

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    Introduction: Maternal obesity is associated with a lipotoxic placental environment that may directly affect placental function and metabolism. Metabolomics is increasingly applied in maternal-fetal medicine for its clinical potential, by identifying specific metabolic profiles, mostly in bio-fluids such as blood, urine or amniotic fluid. This is the first preliminary study analyzing placental metabolomics in normal weight and obese pregnancies. Methods: Placentas at term were collected, washed and immediately frozen in liquid nitrogen at elective cesarean section from 20 normalweight (NW: BMI 18-25 kg/m2) and 18 obese (OB: BMI more than 30 kg/m2) women. Metabolites extraction method was optimized for hydrophilic and lipophilic phases, then analyzed by GC-MS. PLS-DA multivariate statistical analysis was applied. Results: Gestational age, fetal and placental weights were not significantly different between OB and NW.Lipophilic phase analysis in OB showed significantly lower levels of stearic acid and of the LC-PUFA derivatives DHA and arachidonic acid. Hydrophilic phase analysis revealed several metabolites allowing PLS-DA discrimination of data with significantly different levels in OB vs NW: increased glycerol, uracile, hypoxanthine, purine derivative, nicotinamide, glucose-6-P, 3-phosphoglycerate, tyrosine, isoleucine, phenylalanine, leucine, serine; decreased lysine, taurine, inosine, aspartic acid, inositol, gluconic acid, guanosine, glutamine. Conclusion: To our knowledge, this is the first study providing preliminary data on a broad range of metabolites in human obese placentas. Placental metabolome of OB showed a specific fatty acids profile suggesting a disruption of LC-PUFA biomagnification. Moreover, many of the altered metabolites in OB are part of metabolic pathways involved in antioxidant defenses and nucleotide production, as well as energy production and lipid synthesis, supporting a shift towards higher placental metabolism. Metabolic signatures in obese placentas may thus reflect changes occurring in the intrauterine metabolic environment, which may have effect on the development of adult diseases. This study can lay the foundation to further metabolomics placental characterization in the context of obesity. It can represent an additional missing link combining the two separated biological compartments of maternal blood and amniotic fluid, already investigated in other studies. Moreover, future works based on these preliminary data will help identifying a specific placental phenotype of obese pregnancies

    Pre-Dialysis B-Line Quantification at Lung Ultrasound Is a Useful Method for Evaluating the Dry Weight and Predicting the Risk of Intradialytic Hypotension

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    Intradialytic hypotension (IDH) is a frequent and well-known complication of hemodialysis, occurring in about one third of patients. An integrated approach with different methods is needed to minimize IDH episodes and their complications. In this prospective observational study, recruited patients underwent a multiparametric evaluation of fluid status through a lung ultrasound (LUS) with the quantification of B-lines, a physical examination, blood pressure, NT-proBNP and chest X-rays. The evaluation took place immediately before and at the end of the dialysis session, and the patients were divided into IDH and no-IDH groups. We recruited a total of 107 patients. A pre-dialysis B-line number ≥ 15 showed a high sensitivity in fluid overload diagnosis (94.5%), even higher than a chest X-ray (78%) or physical examination (72%) alone. The identification at the beginning of dialysis of <8 B-lines in the overall cohort or <20 B-lines in patients with NYHA 3–4 class are optimal thresholds for identifying those patients at higher risk of experiencing an IDH episode. In the multivariable analysis, the NYHA class, a low pre-dialysis systolic BP and a low pre-dialysis B-line number were independent risk factors for IDH. At the beginning of dialysis, the B-line quantification at LUS is a valuable and reliable method for evaluating fluid status and predicting IDH episodes. A post-dialysis B-line number <5 may allow for an understanding of whether the IDH episode was caused by dehydration, probably due to due to an overestimation of the dry weight
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