303 research outputs found
Flowable Mixtures of Treated Soils for Repairing Damage Caused by Burrowing Animals
No full textThe adoption of flowable mixtures of treated soils is suggested as a sustainable solution for repairing the damage caused by burrowing animals in the Po River embankments. Soil from damaged sites is proposed to be mixed with lime or cement, other additives, and water in order to obtain mixtures with an adequate compromise between viscosity—which is crucial for flowing the mixture into the hole with site machines—and shrinkage that might occur over time according to the hole boundary conditions. Injections of soil-treated mixtures must guarantee hydraulic and mechanical continuity with the existing embankment and reduce shrinkage phenomena that frequently occur with cement–bentonite grout, which is commonly used for this purpose. This study presents an interdisciplinary experimental programme in the search for the best formulation among several recipes of mixtures of soils, collected from four embankments of Po River or its tributaries and treated with lime or cement, different percentages of water, and other additives. The mixtures, after soil classification and viscosity determinations, were then used to create samples for which shrinkage and erosion susceptibility were estimated, respectively, through a non-standard volume measurement procedure and crumb tests. An abacus will be then proposed in order to give, as a first estimation, applicative indications on the best recipe among the investigated mixtures
Assessing River Embankments Stability to FLoods through Unsaturated Centrifuge Testing In transient Seepage conditions - RES FLUCTIS
No full textRiver flood is considered one of the most relevant natural hazards in Europe in terms of economic and human life losses and is frequently due to severe damages experienced by retaining water earthworks, under extreme weather events. Moreover, the risk of breach-induced inundations is expected to increase for many river basins in a climate change scenario and a growing land urbanization. In this framework, a reliable assessment of existing river embankment safety conditions, in serviceability and limit states of operation, represents a key aspect to enhance the resilience of these critical infrastructures (CI). A satisfactory solution to this problem cannot disregard the partially saturated state of the earthfill, neither the role of river stage fluctuations on the seepage process within the embankments. Nevertheless, in the current engineering practice, these aspects are frequently neglected, mainly due to the difficulties in estimating the actual suction distribution and shear strength, providing erroneous conclusions on the effective safety margins towards possible slope instability and overall collapses.
The proposed research project aims at contributing to a better understanding of the effect of time-dependent hydraulic loadings on the stability of the CI through a series of centrifuge tests. The small-scaled physical model will be characterized by a compacted embankment made of a natural silty sand, representative for a tributary river bank, overlying a homogeneous clay foundation layer. To investigate the hydro-mechanical behaviour and the possible failure mechanisms of the CI induced by transient and stationary hydraulic boundary conditions, pore pressure transducers, displacement sensors and high-resolution cameras will be used to monitor the centrifuge tests comprehensively. The 2-week experimental campaign will include model preparation, execution and dismantling of two tests. The project will provide valuable recommendations to improve standards for the stability assessment of river embankments and support the development of more reliable flood risk reduction strategies
Oncological and Functional Outcomes of Radical Cystectomy and Orthotopic Bladder Replacement in Women. Editorial comment
No full textDuring the last decades, orthotopic bladder substitution (OBS) after radical cystectomy for bladder cancer in women has been increasingly proposed. Meanwhile, strict patient selection criteria, improved surgical techniques, long-term follow-up in large patient cohorts, and validated evaluation have defined the role of OBS in men. Several issues must be clarified in women: oncological outcome, complication rates, functional results, quality of life, and sexual function. As a matter of fact, the results of OBS in women are substantially unchanged in the last decade as stated in this paper.
From the oncological standpoint, the patient outcome seems objectively satisfactory but selection criteria are different in the published series. Fortunately, the problem of urethra recurrence seems less relevant in properly selected patients.
However several issues are still a matter of debate. Functional results in terms of continence and hypercontinence are still unsatisfactory because the optimal way to reconstruct the pelvic anatomy is still undefined. Early and late complication rates are poorly evaluated. Little data are also available about the quality of life and sexual function.
Validated evaluation criteria in a large patient cohort are needed to objectively evaluate the results and to improve the substantially unchanged results reported in last decade. It's time to move forward!!
A naked eye aggregation assay for Pb2+ detection based on glutathione-coated gold nanostars
No full textGold nanostars (AuNS) with a mean hydrodynamic size of 40 nm, obtained with a seed-growth approach using a zwitterionic surfactant (laurylsulfobetaine, LSB), were successfully coated with glutathione (GSH), obtaining a stable and purified solid product which can be easily stored and re-dissolved on need in 0.1 M aqueous solution of Hepes buffered at pH 7. Upon exposure to micromolar concentrations of Pb2+ cation, the GSH-coated nano-objects undergo a fast aggregation followed by sedimentation leading to complete precipitation in about an hour. The subsequent disappearing of the intense LSPR extinction can of course be followed spectrophotometrically but, most importantly, can be easily detected with the naked eye. No signs of this event are noticed when other divalent cations are added to the colloidal suspension in the same condition. A careful investigation was performed to study this selectivity and the behaviour of aggregation as a function of time and Pb2+ cation concentration. We demonstrate that an easy, rapid, instrument-free, visual detection of micromolar levels of Pb2+ is thus possible with this assay, showing a good selectivity towards other investigated metal cations
Crambus varii Bassi & I- & To 2012, n.sp.
No full textCrambus varii n.sp. Figs 10, 24, 26 HOLOTYPE: TMSA, without registration number; ♀; [RSA, Western Cape, 33°57’S, 22°32’E] Saasveld George, C [ape] P[rovince], South Africa, H. Geertsema; 26.8.1964; Holotype Crambus varii n. sp. G. Bassi det. 1995, TMSA, (not dissected). PARATYPES (all from RSA): TMSA, without registration number; 1♀; same data as holotype. - TMSA, without registration number; 1♀; idem, 2.2.[19]65 - TMSA, without registration number; 1♀; idem, 1-10.II.1965. - TMSA, without registration number; 1♀; idem, 5.I.1965. - TMSA, without registration number; 13; idem, 26.XII.1964. - TMSA, without registration number; 13; idem, 1.1.1965. - TMSA, without registration number; 1♀; idem, 16.9.1964, De Fin. - TMSA, without registration number; 13; Kogelberg C [ape] P[rovince], Nature Reserve; 6-13.III.1983; Kroon & Molekane, GS 3330 GB. - TMSA, without registration number; 13; Cape Prov[ince], Kogelberg (34 18 BD), 23 Mar[ch] 1981, D.M. Kroon, GS 4193 GB. - TMSA, without registration number; 13; Stellenbosch; 3.3.’[19]21; Ch. K. Brain. - TMSA, without registration number; 13; 1♀, Vyeboom, Caledon Distr[ict]; 10.II.1954; L. Vári, GS 3300 GB. - TMSA, without registration number; 1♀; Saasveld; 5.I.[19]65. - MFNB, without registration number; 2♀♀; RSA, Bontebok NP, Swellendam; 14. 16.XI.1993; leg. Mey & Ebert. - CB, without registration number; 13; Saasveld, C.P.; 23.XII.1964; H. Geertsema, GS 5235 GB. - CB, without registration number; 1♀; Algeria Forestry, Clanwilliam Distr.; 4-10.III.1969; Potgieter & Strydom, GS 5240 GB. - MHNG, without registration number; 1♀, Worcester, Amandel spruit; 18.X.1966; Vári & Potgieter. – TMSA and CB (13), without registration number; 233; 2♀♀, Tsitsikam[m]a Goesabos Forestry; 13-22.III.1979; Potgieter & Scoble. - TMSA, without registration number; 1♀; Cape Prov[ince], Tsitsikam[m]a forest, Goesabos, 33 23 DD; 13-22 Mar 1979; J. Potgieter & M. Scoble, GS 3850 GB. - TMSA, without registration number; 1♀; Tsitsikam [m]a, Ou-brug; 17.III.1979; Potgieter & Scoble. ETYMOLOGY: The species is dedicated to Lajos Vári of the TMSA, author of very valuable entomological collections in Southern Africa. DIAGNOSIS: The combination of forewings without separated submarginal area, male genitalia with fully developed uncus, phallus with dorsoapical tooth and strong cornuti, and female genitalia with very large and strongly sclerotized ostium characterize this species among African Crambus. DESCRIPTION (Fig. 10): Wingspan: male 20-21 mm, female 25-27 mm. Labial palpi 4 X longer than widest diameter of eye, with inner side white and outer side brown with upper margin and tip white. Maxillary palpi white with brown basis. Frons clearly produced, rounded, white. Antennae brown, with silvery costa, serrate in male, simple in female. Ocelli and chaetosemata moderately developed. Head white, with few chestnut brown scales in middle. Patagium laterally brown, white medially. Tegulae dark brown. Thorax white. Abdomen bronze brown to whitish, suffused brown. Forewings ground color bronze brown, lighter in dorsal area; costal area white, wide, and white suffused with chestnut brown toward apex; female with more pointed apex; medial stripe wide, white, reaching outer margin; veins marked by white scales toward outer margin; outer margin with seven subterminal dots, more developed in female; fringes with both short and long scales white with silvery bronzed tip, thus appearing white with medial and terminal lines silvery bronzed. Hindwings white with brown suffusion; fringes white. Fore and midlegs bronze brown; hindlegs whitish, suffused bronze brown. MALE GENITALIA (Fig. 26): Uncus long, sinuous, pointed, moderately bent downward and sclerotized. Two large and spatulate socii cover up to two thirds of length of uncus. Gnathos one third longer than uncus, with apex rounded and bent downward. Tegumen with large base, partially fused with vinculum. Vinculum stout, with large subtriangular dorsal extension. Pseudosaccus small. Valva wide, with membranous cucullus, with well developed and pointed costal and saccular processes and small medial process lamellar. Phallus slightly shorter than whole apparatus, with large subapical tooth; vesica with 5 subtriangular cornuti. FEMALE GENITALIA (Fig. 24): Papillae anales divided into two lobes and apophyses posteriores of medium size. Apophyses anteriores absent. Abdominal segment VIII with narrow tergite and strong and complex sternite. Ostium bursae very large and sclerotized. Ductus bursae longer than corpus bursae, sinuous, sclerotized in proximal two thirds, then fibrous. Ostium and ductus bursae spiculate. Ductus seminalis opening in distal third of ductus bursae. Corpus bursae with two well developed signa. DISTRIBUTION: RSA, Western Cape and Eastern Cape at Tsitsikamma. REMARKS: The presence of socii and both costal and saccular processes relates this species to C. pascuella; female genitalia are also reminiscent of some other Crambus, such as heringiellus Herrich-Schäffer.Published as part of Bassi, Graziano, 2012, New Afrotropical species of the genus Crambus Fabricius, 1798 (Lepidoptera: Pyralidae, Crambinae), pp. 269-286 in Revue suisse de Zoologie 119 (3) on pages 284-286, DOI: 10.5962/bhl.part.150195, http://zenodo.org/record/611826
Verso una politica del limite? Note sul potere e l’azione nel lessico politico di Hannah Arendt
No full textThe starting point of this essay is the Arendtian critique of violence taken as the main interpretative key of the “immense polemic" entertained by the author with the Western philosophical-political tradition. Following this theoretical path, the paper intends to discuss some recurring terms in Arendt’s lexicon. Identifying in Montesquieu and then in Rosa Luxemburg two essential references for the author of The Human Condition, the essay analyzes the questions of the limit and the divisibility of power. The thesis is that, if inserted
in this interpretative frame, Arendt does not belong to the liberal tradition. The theory of action, the praise of the councils and the historical experiences of self-government along with a relational and non-violent conception of power and law are elements that allow us to identify clear radical and libertarian tendencies in Hannah Arendt's thought
Verso una politica del limite? Note sul potere e l’azione nel lessico politico di Hannah Arendt
No full textThe starting point of this essay is the Arendtian critique of violence taken as the main interpretative key of the “immense polemic" entertained by the author with the Western philosophical-political tradition. Following this theoretical path, the paper intends to discuss some recurring terms in Arendt’s lexicon. Identifying in Montesquieu and then in Rosa Luxemburg two essential references for the author of The Human Condition, the essay analyzes the questions of the limit and the divisibility of power. The thesis is that, if inserted in this interpretative frame, Arendt does not belong to the liberal tradition. The theory of action, the praise of the councils and the historical experiences of self-government along with a relational and non-violent conception of power and law are elements that allow us to identify clear radical and libertarian tendencies in Hannah Arendt's thought
A naked eye aggregation assay for Pb2+ detection based on glutathione-coated gold nanostars
No full textGold nanostars (AuNS) with a mean hydrodynamic size of 40 nm, obtained with a seed-growth approach using a zwitterionic surfactant (laurylsulfobetaine, LSB), were successfully coated with glutathione (GSH), obtaining a stable and purified solid product which can be easily stored and re-dissolved on need in 0.1 M aqueous solution of Hepes buffered at pH 7. Upon exposure to micromolar concentrations of Pb2+ cation, the GSH-coated nano-objects undergo a fast aggregation followed by sedimentation leading to complete precipitation in about an hour. The subsequent disappearing of the intense LSPR extinction can of course be followed spectrophotometrically but, most importantly, can be easily detected with the naked eye. No signs of this event are noticed when other divalent cations are added to the colloidal suspension in the same condition. A careful investigation was performed to study this selectivity and the behaviour of aggregation as a function of time and Pb2+ cation concentration. We demonstrate that an easy, rapid, instrument-free, visual detection of micromolar levels of Pb2+ is thus possible with this assay, showing a good selectivity towards other investigated metal cations
Sand boil observations and geotechnical characterization of river embankments for the development of a backward erosion piping database
No full textSand boil formation at the toe of river embankments is the typical manifestation of initiation and progression of an internal erosion process known as backward erosion piping, which is recognized to be a major concern in many river systems worldwide. In Italy, more than 130 sand boils have been detected along the Po River, many of them experiencing recurrent reactivations during high-water events. As a consequence of such widespread occurrence and the risk for the safety of the surrounding territory and human activities, the development of a sand boil database has been increasingly seen as an essential tool for identifying triggering conditions and giving priorities for the implementation of mitigation measures. In recent years, as part of the activities of the European Project LIFE SandBoil, a GIS-based web application was developed in order to catalogue the sand boils observed along the Po River. The database allows keeping records of a comprehensive set of information, e.g. geometry of the river embankments, subsoil stratigraphy, data on the sand boils, and characteristics of high- water events. Taking a piping-prone cross-section along the Po River as reference, the paper aims at describing the main features of this versatile and flexible tool, which is meant to help in understanding the conditions causing initiation and the sand boil dynamics, as well as to support flood risk management against backward erosion piping
Andrea Caffi e Hannah Arendt. Appunti per un dialogo postumo [Andrea Caffi and Hannah Arendt. Notes for a Posthumous Dialogue]
No full textThe current paper primarily compares Caffi’s essay Violence and Sociability (1946) to Arendt’s essay On Violence (1969). Starting from the historical context of «politics», the journal that published Violence and Sociability and for which Arendt was a contributor, I will reconstruct the common themes that emerge from their reflections. Through demonstrating the comparability of Caffi’s thought with Arendtian political theory, the aim is to argue that Caffi is an author unjustly condemned to oblivion
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