979 research outputs found
The Ussana “Fm”: insight about the Sardinian rift from a syn-tectonic unit evolving through space and time
The meaning and the space-and-time variable depositional features of the Ussana “Fm” and of the related
coeval units, base of the Late Oligocene - Miocene succession of the Sardinian rift, are discussed. These features, and
the presence/absence itself of the Ussana Fm, are related to tectonic and paleomorphologic characters of the Sardinian
rift shoulders and their evolution. The features of the Ussana Fm evidence the changing characteristics of the Sardinian
rift up to the southern Corsica area. Giving the extremely variable characters of the stratigraphic sections of the Ussana
Fm from S to N and also at short distance, a possible lithostratigrahic upgrade of the unit to litostratigrpahic group is
proposed
THE "GERMANIC" TRIASSIC OF SARDINIA (ITALY): A STRATIGRAPHIC, DEPOSITIONAL AND PALAEOGEOGRAPHIC REVIEW
The collection of new lithostratigraphical and sedimentological data has allowed to re-examine the Triassic sedimentation cycle in Sardinia The most important outcrops have been revisited and their general setting reinterpreted. A detailed and homogeneous depositional, palaeoenvironmental and stratigraphic picture is proposed, pointing to the analogies with both the typical Germanic Triassic of Central Europe, and the Middle Triassic Sephardic domain of Western Europe and North Africa. The lower, essentially siliciclastic, lithostratigraphic units, resting discordantly on the Hercynian Palaeozoic basement, resemble the "Buntsandstein" facies association. They are generally of Anisian age. Their depositional environments range from high-energy continental to transitional environments to the floodplain, where a shallow, epicontinental sea gradually transgressed. Overlaying these are the carbonate units of the "Muschelkalk" facies association. They are generally dolomitic at the bottom passing to calcareous at the top. These deposits, generally of Ladinian age, formed in the various subenvironments of a carbonate ramp. The few Upper Triassic successions in Sardinia point to the existence, during this period, of diverse depositional conditions in the North (Nurra) and South (Sulcis) of the island. In southern Sardinia, lagoon to shallow sea carbonate shelf deposition predominates, with minor amounts of evaporites and siliciclastics. By contrast, in Northern Sardinia mixed evaporitic-siliciclastic-carbonate facies of paralic-continental (mudflat), locally restricted lagoonal environments, were deposited. The latter are very similar to the classic Germanic "Keuper" facies. These data suggest that the Upper Triassic successions in Southern Sardinia can be set in a transitional environmental context between the open Alpine-Tethyan domain and the Germanic Triassic proper. An attempt has been made to correlate these successions with the Middle to Late Triassic eustatic cycles. 
iPSCs-Based Neural 3D Systems: A Multidimensional Approach for Disease Modeling and Drug Discovery
Induced pluripotent stem cells (iPSCs)-based two-dimensional (2D) protocols have offered invaluable insights into the pathophysiology of neurological diseases. However, these systems are unable to reproduce complex cytoarchitectural features, cell-cell and tissue-tissue interactions like their in vivo counterpart. Three-dimensional (3D)-based culture protocols, though in their infancy, have offered new insights into modeling human diseases. Human neural organoids try to recapitulate the cellular diversity of complex tissues and can be generated from iPSCs to model the pathophysiology of a wide spectrum of pathologies. The engraftment of iPSCs into mice models and the improvement of differentiation protocols towards 3D cultures has enabled the generation of more complex multicellular systems. Consequently, models of neuropsychiatric disorders, infectious diseases, brain cancer and cerebral hypoxic injury can now be investigated from new perspectives. In this review, we consider the advancements made in modeling neuropsychiatric and neurological diseases with iPSC-derived organoids and their potential use to develop new drugs
Treatment of esophageal achalasia in children: Today and tomorrow
Esophageal achalasia (EA) is a rare esophageal motility disorder in children. Laparoscopic Heller myotomy (LHM) represents the treatment of choice in young patients. Peroral endoscopic myotomy (POEM) is becoming an alternative to LHM. The aim of this study is to evaluate the effectiveness, safety, and outcomes of POEM vs LHM in treatment of children with EA.
Data of pediatric patients with EA, who underwent LHM and POEM from February 2009 to December 2013 in two centers, were collected.
Eighteen patients (9 male, mean age: 11.6 years; range: 2-17 years) were included. Nine patients (6 male, mean age: 10.7 years; range: 2-16 years) underwent LHM, and the other 9 (3 males, mean age: 12.2 years; range: 6-17 years) underwent POEM procedure. Mean operation time was shorter in POEM group compared with LHM group (62/149 minutes). Myotomy was longer in POEM group than in LHM group (11/7 cm). One major complication occurred after LHM (esophageal perforation). No clinical and manometric differences were observed between LHM and POEM in follow-up. The incidence of iatrogenic gastroesophageal reflux disease was low (1 patient in both groups).
Results of a midterm follow-up show that LHM and POEM are safe and effective treatments also in children. Besides, POEM is a mini-invasive technique with an inferior execution timing compared to LHM. A skilled endoscopic team is mandatory to perform this procedur
Sporadic flat ileal adenocarcinoma: an intriguing challenge in the comprehension of a rare neoplasia and its genesis. Case report and review of literature
Small bowel adenocarcinoma is a rare tumor, with a still not well studied tumorigenesis process, usually presenting in an advanced stage. The clinical diagnosis is often difficult; surgery is the treatment of choice when feasible, while the chemotherapic approach is still not well codified. We describe the case of a 71-yr-old male patient, presenting with an acute right abdomen. At laparotomy the terminal ileum appeared chronically inflamed and thickened. An ileocecal resection with laterolateral
ileocolic anastomosis was performed. The gross appearance resembled an inflammatory bowel disease, but microscopic examination revealed the extensive presence of an infiltrating ileal adenocarcinoma. Literature about small bowel adenocarcinoma has been reviewed for better understanding its pathogenesis
Analysis of particle size distribution in municipal wastewaters
Innovative membrane filtration plants for municipal wastewaters are being developed and need the support of reliable filtration models in the designing phase. In the past, semi-empirical filtration models for membrane processes have been proposed. At present, the most prominent works point out the importance of particle poly-dispersity in the development of reliable models but fail into the implementation of probability density functions (PDFs) capable of an accurate fitting of the experimental particle size distribution (PSD). We report the experimental PSDs of two different municipal wastewater samples, obtained through the laser diffraction technique. The experimental results show that the laser diffraction technique can characterize wastewater particle dimensions both in the colloidal and supra-colloidal regions. The experimental study is complemented by a comparative analysis in which many PDFs are used to fit the experimental PSDs through a least-squares approach. Some of these PDFs are proposed here for the first time to fit experimental wastewater PSDs. Among the PDFs considered for the statistical modeling, the three-parameter lognormal and the Burr PDFs are demonstrated to provide satisfactory fitting, whereas the other considered functions fail. This result is confirmed by the analysis of both the available wastewater samples
Covered self-expandable metal stents for pancreatic duct stricture: a systematic review and meta-analysis
Background and study aims Placement of a covered (C)-self-expandable metal stent (SEMS) has been recently investigated as an alternative endoscopic treatment for main pancreatic duct stricture (MPDS) in chronic pancreatitis. Our aim was to carry out a systematic review and meta-analysis of studies quantifying efficacy and safety of C-SEMSs in the management of MPDS.Methods A multiple database search was performed, including MEDLINE, Embase and Cochrane Library, from January 2000 to September 2020, to identify studies reporting the efficacy and safety of C-SEMSs in patients with MPDS. Stricture and pain resolution were investigated. Other outcomes included technical success, stent migration, stricture recurrence and need for repeated stent placement. Pancreatitis, severe abdominal pain requiring stent removal and de-novo stricture were recorded as complications.Results Nineteen studies were identified, which included a total of 300 patients. C-SEMSs showed a pooled stricture resolution rate of 91 % [95 % confidence interval (CI), 85 %-96 %] and a pooled pain resolution rate of 92 % (95 % CI, 85 %-98 %). The pooled proportion for stricture recurrence was equal to 6 % (95 % CI, 1 %-14 %), while stent migration occurred in 33 of 300 patients, the pooled proportion being 7 % (95 % CI 1 %-15 %). The pooled mean stent duration was 133 days (95 % CI, 100-166 days). The most common complication was pancreatitis (3 %, 95 % CI 0 %-8 %), while de-novo stricture pooled proportion was 2 % (95 % CI, 0 %-5 %).Conclusions C-SEMSs are effective and safe in the treatment of MPDS. However, there is a significant need for further high-quality, well-designed studies to produce evidence-based data on short and long-term efficacy, safety, costs of C-SEMSs, and also optimal stent duration
Photocatalytic reactions of a nickel(II) annulene complex incorporated in polymeric structures
The photochemical reactions of the Ni(II) annulene complex, [NiII([5,7,12,14]-tetra methyl dibenzo[2,3- b:2,3-b,i][1,4,8,11]tetraaza[14]annulenate)], grafted into a poly(isobutylene-alt-maleate) backbone were investigated in aqueous media. The grafted Ni(II) complex becomes soluble in aqueous and organic solvents where the strands form aggregates with medium-dependent shapes. Irradiation of the polymer at 532 or 351 nm produce charge-separated macrocyclic pendants, CS, with a lifetime s 30 ns. CS reacts with electron donors and acceptors before it decays with a lifetime s 1 ms. In parallel to the decay of CS, an excited state-excited state annihilation process gives rise to luminescence whose spectrum spans wavelengths shorter than the wavelength of the irradiation, lex > 500 nm. Theoretical calculations were carried out with the aim of understanding the morphology and structures of strand aggregates, to confirm the nature of reaction products and to account for the spectroscopic and photochemical properties of the Ni(II) pendants. The endothermic reduction of CO2 to CO by S(IV) species was used as a test of the Ni(II) complex´s ability to photocatalyze the reaction. In the photoprocess, the Ni(II) complex fulfills the double role of antenna and catalyst.Fil: Estiu, G.. University Of Notre Dame-indiana; Estados UnidosFil: Ferraudi, G.. University Of Notre Dame-indiana; Estados UnidosFil: Lappin, A. G.. University Of Notre Dame-indiana; Estados UnidosFil: Ruiz, Gustavo Teodosio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico la Plata. Instituto de Investigaciones FisicoquĂmicas TeĂłricas y Aplicadas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Vericat, Carolina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico la Plata. Instituto de Investigaciones FisicoquĂmicas TeĂłricas y Aplicadas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Costamagna, J.. Universidad de Santiago de Chile; ChileFil: Villagrán, M.. Universidad de Santiago de Chile; Chil
Environmental Assessment of Solar Photo-Fenton Processes at Mild Condition in the Presence of Waste-Derived Bio-Based Substances
[EN] The assessment of environmental sustainability has assumed great importance during the study and implementation of a new process, including those aimed to waste valorization and reuse. In this research, the environmental performance of the photo-Fenton processes was evaluated using the life cycle assessment (LCA) methodology. In particular, photo-Fenton conducted in mild conditions (almost neutral pH), using soluble bio-organic substances as auxiliary agents were compared with the "classic" photo-Fenton run at pH 2.8. The evaluation was carried out both, at the laboratory level and at pilot plant scale. LCA analysis shows that working in mild conditions reduces the environmental burden associated with the use of chemicals. On the other hand, the occurring drop in effectiveness significantly increases the overall impact, thus evidencing the need of considering the process as a whole.Costamagna, M.; Arqués Sanz, A.; Lo-Iacono-Ferreira, VG.; Bianco Prevot, A. (2022). Environmental Assessment of Solar Photo-Fenton Processes at Mild Condition in the Presence of Waste-Derived Bio-Based Substances. Nanomaterials. 12(16):1-13. https://doi.org/10.3390/nano12162781113121
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