2,178 research outputs found
Study made of large amplitude fuel sloshing
Study of resonant oscillations of an ideal fluid in a cylindrical tank is used to obtain a better understanding of fuel sloshing in large liquid booster. More realistic structural design criteria may be formulated when the dynamic response of the liquid in a cylindrical tank can be predicted analytically
URACHAL CYST: AN UNSPECTED COMPLICATION
The urachus is the remnant of the allantois, which usually becomes obliterated shortly after birth. Urachal remnants
due to an incomplete obliteration of different portion of the urachus are rare, but they need to be treated surgically because
of their potential for infectious complications and malignant degeneration. We present a case report with an unespected postoperative
complication. M.E., a 10 years old boy, came to the Accident and Emergency Department for an acute abdominal
pain, without other symptoms, twice in one year. The blood tests, urine sample and voiding cystourethrogram were normal.
The ultrasound scan showed a thickened urachal duct. After antibiotic and anti-inflammatory therapy for two weeks, we
performed laparoscopic surgery. In the second postoperative day the patient showed abdominal pain and hematuria. An ultrasound
scan and a voiding cystourethrogram showed a leak from the dome of bladder. We performed an open surgery to
close the defect on the bladder’s dome. The patient was discharged in 10th postoperative day. Now he is healthy. Clinically
manifest persistent urachal anomalies are rare, but they carry a risk of recurrent infection and subsequent malignant degeneration.
For these reasons the radical excision of the remnant is suggested. Today, due to the large laparoscopic experience,
all the reports showed that this technique can be used safely, but we have to pay attention to all steps of the procedure. This
case is a paradigmatic situation and it illustrates the importance of a meticulous technique during the excision of urachal
remnant. Indeed even if laparoscopic excision could be safe and effective, it is not free of complication
Functional characterization of the sea urchin sns chromatin insulator in erythroid cells
Chromatin insulators are regulatory elements that determine domains of genetic functions. We have previously described the characterization of a 265 bp insulator element, termed sns, localized at the 3' end of the early historic H2A gene of the sea urchin Paracentrotus lividus. This sequence contains three cis-acting elements (Box A, Box B, and Box C+T) all needed for the enhancer-blocking activity in both sea urchin and human cells. The goal of this Study was to further characterize the sea urchin sns insulator in the erythroid environment. We employed colony assays in human (K562) and mouse (MEL) erythroid cell lines. We tested the capability of sns to interfere with the communication between the 5HS2 enhancer of the human beta-globin LCR and the gamma-globin promoter. We found that the sns sequence displays directional enhancer-blocking activity. By the use of antibodies against known DNA binding proteins, in electrophoretic mobility shift assays, we demonstrated the binding of the erythroid-specific GATA-1 and the ubiquitous Oct-1 and Sp1 transcription factors. These factors bind to Box A, Box B, and Box C+T, respectively, in both K562 and MEL nuclear extracts. These results may have significant implications for the conservation of insulator function ill evolutionary distant organisms and may prove to be of practical benefit in gene transfer applications for erythroid disorders such as hemoglobinopathies and thalassemias
The spectral element method as an effective tool for solving large scale dynamic soil-structure interaction problems
The spectral element method (SEM) is a powerful numerical technique naturally suited for wave propagation and dynamic soil-structure interaction (DSSI) analyses. A class of SEM has been widely used in the seismological field (local or global seismology) thanks to its capability of providing high accuracy and allowing the implementation of optimized parallel algorithms. We illustrate inthis contribution how the SEM can be effectively used also for the numerical analysis of DSSI problems, with reference to the 3D seismic response of a railway viaduct in Italy. This numerical analysis includes the combined effect of: a) strong lateral variations of soil properties; b) topographic amplification; c) DSSI; d) spatial variation of earthquake ground motion in the structural response. Some hints on the work in progress to effectively handle nonlinear problems with SEM are also given
HYPERPLASIA OF THYMIC GLAND: LEFT VIDEO-ASSISTED THORACOSCOPIC APPROACH
Hyperplasia of thymic gland is a rare benign entity that should be considered in the differential diagnosis of anterior
mediastinal masses in children and young adolescents. We report a case of a patient with a thymic mass, diagnosed occasionally
for respiratory symptoms and treated by video-assisted thoracoscopic surgery. A previously healthy 10 years-old boy
presented to our hospital for retrosternal pain and dyspnea with restriction to daily activities from four months. Diagnostic
imaging was performed, including a chest x-ray and a magnetic resonance imaging, showing a large homogeneous anterosuperior
mediastinal mass, more extended on the left side. The additional laboratory analysis, considered essential for differential
diagnosis with myasthenia gravis and lymphoma, resulted negative. In view of these findings, our patient underwent
to video assisted thoracoscopy with left-sided approach for a total resection of thymus and perithymic fat. The patient made
an excellent recovery without postoperative complications and was discharged from the hospital four days later. Histopathological
examination showed a normal thymic architecture like a true thymic hyperplasia. At follow up, chest x-ray was normal
in absence of pleural and parenchimal alterations. Thoracoscopic thymectomy is a safe technique that allows to achieve the
goal of early thymectomy with the advantages of less invasive procedure
Photodoping and in-gap interface states across the metal-insulator transition in LaAlO3/SrTiO3 heterostructures
By using scanning tunneling microscopy/spectroscopy we show that the interface between LaAlO3 and SrTiO3 band insulators is characterized by in-gap interface states. These features were observed in insulating as well as conducting LaAlO3/SrTiO3 bilayers. The data show how the interface density of states evolves across the insulating to metal transition, demonstrating that nanoscale electronic inhomogeneities in the system are induced by spatially localized electrons
Quaternary marine and continental unconformity-bounded stratigraphic units of the NW Sicily coastal belt
In the coastal sector of NW Sicily, the regional correlation of relevant unconformities recognised within the Quaternary sedimentary successions allowed the mapping of seven unconformitybounded stratigraphic units (UBSUs). The regional unconformities are marine or subaerial erosional surfaces, as well as non-depositional surfaces, locally marked by paleosoils. The erosional surfaces were produced from marine abrasion, surface water overland/ concentrated flow, river erosion, karst solution, mass movement, or wind erosion. The main lithofacies of the Quaternary UBSUs consist of: (a) marine and coastal bioclastic calcarenites, (b) aeolian sandstones, (c) river deposits, (d) colluvial deposits, (e) talus slope deposits, (f) landslide deposits, and (g) chemical carbonates (travertines and speleothems). Quaternary environmental changes, due to tectonics, climate, and sea-level oscillations, are the causes that favoured the development of erosion/deposition processes responsible for the genesis of unconformities and deposits. As a result, through the UBSU map of the NW Sicilian coastal belt, it is possible to: (i) recognise stratigraphic units controlled by tectonic, climatic, and environmental processes (and their interplay) and (ii) detect Quaternary sedimentary evolution
Long-term use of deferiprone significantly enhances left-ventricular ejection function in thalassemia major patients
Synthesis, antiproliferative activity, and mechanism of action of a series of 2-{[2E]-3-phenylprop-2-enoylamino}benzamides
Several new 2-{[2E]-3-phenylprop-2-enoylamino}benzamides 12a-s and 17t-v were synthesized by stirring in pyridine the (E)-3-(2-R1-3-R2-4-R3-phenyl)acrylic acid chlorides 11c-k and 11t-v with the appropriate anthranilamide derivatives 10a-c or the 5-iodo anthranilic acid 13. Some of synthesized compounds were evaluated for their in vitro antiproliferative activity against the full NCI tumor cell line panel derived from nine clinically isolated cancer types (leukemia, non-small cell lung, colon, CNS, melanoma, ovarian, renal, prostate and breast). COMPARE analysis, effects on tubulin polymerization in cells and with purified tubulin, and effects on cell cycle distribution for 17t, the most active of the series, indicate that these new antiproliferative compounds act as antitubulin agent
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