29 research outputs found
Bilateral ureteropelvic disruption following blunt abdominal trauma: Case report
<p>Abstract</p> <p>Background</p> <p>Ureteral injury occurs in less than 1% of blunt abdominal trauma cases, partly because the ureters are relatively well protected in the retroperitoneum. Bilateral ureteral injury is extremely rare, with only 10 previously reported cases. Diagnosis may be delayed if ureteric injury is not suspected, and delay of 36 hours or longer has been observed in more than 50% of patients with ureteric injury following abdominal trauma, leading to increased morbidity.</p> <p>Case presentation</p> <p>A 29-year-old man was involved in a highway motor vehicle collision and was ejected from the front passenger seat even though wearing a seatbelt. He was in a preshock state at the scene of the accident. An intravenous line and left thoracic drain were inserted, and he was transported to our hospital by helicopter. Whole-body, contrast-enhanced computed tomography (CT) scan showed left diaphragmatic disruption, splenic injury, and a grade I injury to the left kidney with a retroperitoneal haematoma. He underwent emergency laparotomy. The left diaphragmatic and splenic injuries were repaired. Although a retroperitoneal haematoma was observed, his renal injury was treated conservatively because the haematoma was not expanding. In the intensive care unit, the patient's haemodynamic state was stable, but there was no urinary output for 9 hours after surgery. Anuresis prompted a review of the abdominal x-ray which had been performed after the contrast-enhanced CT. Leakage of contrast material from the ureteropelvic junctions was detected, and review of the repeat CT scan revealed contrast retention in the perirenal retroperitoneum bilaterally. He underwent cystoscopy and bilateral retrograde pyelography, which showed bilateral complete ureteral disruption, preventing placement of ureteral stents. Diagnostic laparotomy revealed complete disruption of the ureteropelvic junctions bilaterally. Double-J ureteral stents were placed bilaterally and ureteropelvic anastomoses were performed. The patient's postoperative progress was satisfactory and he was discharged on the 23<sup>rd </sup>day.</p> <p>Conclusion</p> <p>Diagnosis of ureteral injury was delayed, although delayed phase contrast-enhanced CT and abdominal x-rays performed after CT revealed the diagnosis early. Prompt detection and early repair prevented permanent renal damage and the necessity for nephrectomy.</p
Microstructure, Tensile Deformation and Fracture Behaviour of Aluminium Alloy 7055
The microstructure, tensile deformation and fracture behaviour of aluminium alloy 7055 were studied. Detailed optical and electron microscopy observations were made to analyse the as-received microstructure of the alloy. Detailed transmission electron microscopy observations revealed the principal strengthening precipitates to be the hexagonal disc-shaped η′ phase of size 2 mm×20 mm and fully coherent with the aluminium alloy matrix, the presence of spheroidal dispersoids, equilibrium grain-boundary η precipitates and narrow precipitate-free zones adjacent to grain-boundary regions. It is shown that microstructural characteristics have a profound influence on tensile deformation and fracture behaviour. Tensile test results reveal the alloy to have uniform strength and ductility in the longitudinal and transverse orientations. Strength marginally decreased with an increase in test temperature but with a concomitant improvement in elongation and reduction in area. No change in macroscopic fracture mode was observed with sample orientation. Fracture, on a microscopic scale, was predominantly ductile comprising microvoid nucleation, growth and coalescence. The tensile deformation and fracture process are discussed in the light of the competing influences of intrinsic microstructural effects, matrix deformation characteristics, test temperature and grain-boundary failure
A brief perspective on the diverging theories of lymphatic targeting with colloids
Karthik Siram,1 Gregory Marslin,2 Chellan Vijaya Raghavan,1 Krishnamoorthy Balakumar,1 Habibur Rahman,1 Gregory Franklin3 1Department of Pharmaceutics, PSG College of Pharmacy, Coimbatore, India; 2Centre for the Research and Technology of Agro-Environment and Biological Sciences, University of Minho, Braga, Portugal; 3Department of Integrative Plant Biology, Institute of Plant Genetics, Polish Academy of Sciences, Poznan, Poland Abstract: For targeted delivery of colloids to the lymphatic system, the colloids should efficiently reach and remain in the lymphatics for a considerable period of time. As per the current knowledge, diffusion and phagocytosis are the two mechanisms through which colloids reach the lymphatic system. Several parameters including particle size and charge have been shown to affect the direct uptake of colloids by the lymphatic system. Although many researchers attached ligands on the surface of colloids to promote phagocytosis-mediated lymphatic delivery, another school of thought suggests avoidance of phagocytosis by use of carriers like polyethylene glycol (PEG)ylated colloids to impart stealth attributes and evade phagocytosis. In this perspective, we weigh up the paradoxical theories and approaches available in the literature to draw conclusions on the conditions favorable for achieving efficient lymphatic targeting of colloids. Keywords: lymphatic targeting, colloids, PEGylation, phagocytosi
Optimal strategies for transitions in simulated moving bed chromatography
Simulated moving bed chromatography (SMBC) has emerged as a significant separation technology in the process industry. SMB operating parameters are chosen to satisfy various performance objectives such as maximization of purity or productivity and the choice of the objective is generally guided by process economics. From an industrial perspective, the SMB must be operated flexibly, so that the same unit can be operated to satisfy different objectives. Transiting from one objective to another entails large transition periods, resulting in an economic loss. We propose use of optimal transitions as an approach to minimizing transition time, reducing use of feed and desorbent during transition as well as reduction in off-specification product relative to a non-optimal, step change approach. Optimal transitions can also be used in recovering from feed upset scenarios. The above methods are demonstrated using simulations on a benchmark SMBC process for separation of glucose and fructose using Ca++ exchange resin. (C) 2015 Elsevier Ltd. All rights reserved
Spectroscopic Characterization and Modeling of Quadrupolar Charge-Transfer Dyes with Bulky Substituents
Joint experimental and theoretical work is presented on two quadrupolar D-π-A-π-D chromophores characterized by the same bulky donor (D) group and two different central cores. The first chromophore, a newly synthesized species with a malononitrile-based acceptor (A) group, has a V-shaped structure that makes its absorption spectrum very broad, covering most of the visible region. The second chromophore has a squaraine-based core and therefore a linear structure, as also evinced from its absorption spectra. Both chromophores show an anomalous red shift of the absorption band upon increasing solvent polarity, a feature that is ascribed to the large, bulky structure of the molecules. For these molecules, the basic description of polar solvation in terms of a uniform reaction field fails. Indeed, a simple extension of the model to account for two independent reaction fields associated with the two molecular arms quantitatively reproduces the observed linear absorption and fluorescence as well as fluorescence anisotropy spectra, fully rationalizing their nontrivial dependence on solvent polarity. The model derived from the analysis of linear spectra is adopted to predict nonlinear spectra and specifically hyper-Rayleigh scattering and two-photon absorption spectra. In polar solvents, the V-shaped chromophore is predicted to have a large HRS response in a wide spectral region (approximately 600–1300 nm). Anomalously large and largely solvent-dependent HRS responses for the linear chromophores are ascribed to symmetry lowering induced by polar solvation and amplified in this bulky system by the presence of two reaction fields
Nasa global change master directory: an implementation of asynchronous management protocol in a heterogeneous distributed environment
The Global Change Master Directory (GCMD) is an earth science repository that specifically tracks research data on global climatic change. The GCMD is migrating from a centralized architecture to a globally distributed replicated heterogeneous federated system. One of the greatest challenges facing database research is the integration of heterogeneous systems without compromising the local autonomy, reliability and transparency of the various databases that are participating in the integration. This paper discusses these challenges in the context of the design and implementation of the next version of the GCMD software (Version 8.0). The proposed system has been designed and developed using an object-oriented system architecture based on Java, RMI (Remote Method Invocation) and JDBC. This system enables other sources to be integrated into the GCMD system, with limited changes to the local system itself. This paper describes the components of the GCMD system and addresses the issues of heterogeneity, distribution and autonomy. Keywords