Skull metastasis of hepatocellular carcinoma in normal liver: Case report

Background: So far hepatocellular carcinoma (HCC) is the most common liver malignant tumour; it is rarely encountered on a healthy liver (9). The metastasis from HCC cancer are seen in lymph nodes (16%–40%) and lungs (34%–70%), (1,3,4,5,7,8), bone metastasis is unusual and some locations stay rare among them the skull (2,4,5). We report here a case of a patient operated in our department for skull metastasis. That patient was followed for hepatocellular carcinoma in digestive surgery department. Case presentation: The patient is a 57 years old male presenting HCC on healthy liver, the patient was referred to our department by digestive surgery colleagues to manage a parietal subcutaneous mass; brain CT scans were performed objectified a calvarial osteolytic process. We remove the tumour and we put a cranioplasty using surgical cement, later the histological studies were in favour of secondary location of hepatocellular carcinoma. Conclusion: Skull metastasis from hepatocellular carcinoma is rare, reporting such cases strengthen the idea of evoking HCC metastasis in the differential diagnosis of cranial subcutaneous mass

Preparation and characterization of electrolytic alumina deposit on austenitic stainless steel

Conversion coating modified by alumina has been studied as a way for improving the resistance to thermal oxidation of an austenitic stainless steel. Conversion coating, characterized by a particular morphology and strong interfacial adhesion with the substrate, facilitate the electrochemical deposition of ceramic layers and enhance their adhesion to the substrate. The influence of the current density and treatment time on alumina deposit was studied using statistical experimental designs like Doehlert uniform shell design. After heating, coatings present a continuous composition gradient with refractory compounds at the surface. The behavior at high temperature (1000 8C) of the alumina coating was investigated. The presence of alumina increases the oxidation resistance of an austenitic stainless steel at 1000 8C. The morphology and the chemical composition of the deposit are analyzed. Results on the thermal stability of coating on austenitic stainless steel are presented

Ewing’s sarcoma of the mobile spine: Three unusual observations

Background. Ewing’s sarcoma is a bony highly malignant tumour, it occurs most frequently in the second decade of life. Ewing’s sarcoma is a rare affection, located usually in the pelvis, the femur, the humerus, the ribs, the mandible and clavicle, other location are rare especially in the spine. We report three cases of spinal Ewing’s sarcoma, two primary spine locations and one on young adult with unusual clinical presentation. Cases presentation Case 1. The first patient is a girl of 14 years old without past medical history. She presented initially two months before consultation a neck pain followed days after by a weakness of the left upper limb; the spine imaging performed objectified a destructive process of C2 with a spinal cord compression. The patient was operated beneficiating of a spinal cord decompression and a subtotal removal of the tumour. The pathologist’s results were in favour of Ewing’s sarcoma and the patient was oriented to oncology. Case 2. The second patient is a man of 31 years old operated five years before he consulted for shoulder Ewing’s sarcoma followed by chemotherapy and radiotherapy, he presented two months before consultation a cauda equina syndrome. Spine MRI objectified a double location of an epidural tumour at T3-T4 and S1-S2 levels. The patient was operated beneficiating of subtotal removal of the tumour. The laboratory exam results were in favour of Ewing’s sarcoma and the patient was oriented to oncology. Case 3. The third patient is a 6 years old boy who presented a 1 month history of low back pain followed by a rapidly deteriorating weakness of both lower limbs over a weak. On examination there was bilateral spastic paraplegia, hypoesthesia below the level of Th10 and a urinary retention. The MRI imaging revealed a lesion on the levels Th8, Th9 and Th10 vertebras involving the body, pedicle, lamina, and the transverse process on the left side with an epidural invasion compressing the spinal cord. The tumour was radically removed. Pathology report was in favour of Ewing’s sarcoma. Two weeks after surgery the patient was able to walk. He was referred for adjuvant systemic chemotherapy. Conclusion. Ewing’s sarcoma is rare malignant tumour. The location in the spine exposes the patient to more complications because of the neurostructures compression. The surgical total removal followed by radio and chemotherapy is the only option with the best prognostic and guaranties an acceptable life quality

Nadgledanje statorskih i rotorskih pogrešaka asinkronog motora napajanog inverterom koristeći estimatore stanja

The paper deals with the application of the Extended Kalman Filter and the Extended Luenberger Observer algorithms for the stator and rotor fault detection of the induction motor fed by PWM inverter. The induction motor conditions are analyzed using estimated rotor and stator-winding resistance. Mathematical models of the extended state estimators are presented, in which the stator and rotor resistances are added as additional electromagnetic state variables. Experimental results for the inverter-fed induction motor, with shorted stator-turns and broken rotor bars, are presented and analysed.Ovaj radi proučava primjenu algoritama proširenog Kalmanovog filtra i proširenog Luenbergerovog observera za detekciju pogreške statora i rotora asinkronog motora napajanog PWM inverterom. Stanja asinkronog motora analizirana su korištenjem estimiranog otpora statorskih i rotorskih namota. Prikazani su matematički modeli proširenih estimatora stanja u kojima su otpori statora i rotora dodani kao dodatne varijable stanja. Prikazani su i analizirani eksperimentalni rezultati za asinkroni motor napajan inverterom s kratko spojenim statorskim namotima i prekinutim rotoskim polugama

The convex hull for a random acceleration process in two dimensions

We compute exactly the mean perimeter and the mean area of the convex hull of a random acceleration process of duration T in two dimensions. We use an exact mapping that relates, via Cauchy's formulae, the computation of the perimeter and the area of the convex hull of an arbitrary two dimensional stochastic process [x(t); y(t)] to the computation of the extreme value statistics of the associated one dimensional component process x(t). The latter can be computed exactly for the one dimensional random acceleration process even though the process in non-Markovian. Physically, our results are relevant in describing theaverage shape of a semi-flexible ideal polymer chain in two dimensions.Comment: 17 pages, 7 figures, accepeted in Journal of Physics A: Mathematical and Theoretica

Using self-organizing maps to investigate environmental factors regulating colony size and breeding success of the White Stork (Ciconia ciconia)

We studied variations in the size of breeding colonies and in breeding performance of White Storks Ciconia ciconia in 2006–2008 in north-east Algeria. Each colony site was characterized using 12 environmental variables describing the physical environment, land-cover categories, and human activities, and by three demographic parameters: the number of breeding pairs, the number of pairs with chicks, and the number of fledged chicks per pair. Generalized linear mixed models and the self-organizing map algorithm (SOM, neural network) were used to investigate effects of biotic, abiotic, and anthropogenic factors on demographic parameters and on their relationships. Numbers of breeding pairs and of pairs with chicks were affected by the same environmental factors, mainly anthropogenic, which differed from those affecting the number of fledged chicks per pair. Numbers of fledged chicks per pair was not affected by colony size or by the number of nests with chicks. The categorization of the environmental variables into natural and anthropogenic, in connection with demographic parameters, was relevant to detect factors explaining variation in colony size and breeding parameters. The SOM proved a relevant tool to help determine actual dynamics in White Stork colonies, and thus to support effective conservation decisions at a regional scale

Pattern formation in 2-frequency forced parametric waves

We present an experimental investigation of superlattice patterns generated on the surface of a fluid via parametric forcing with 2 commensurate frequencies. The spatio-temporal behavior of 4 qualitatively different types of superlattice patterns is described in detail. These states are generated via a number of different 3--wave resonant interactions. They occur either as symmetry--breaking bifurcations of hexagonal patterns composed of a single unstable mode or via nonlinear interactions between the two primary unstable modes generated by the two forcing frequencies. A coherent picture of these states together with the phase space in which they appear is presented. In addition, we describe a number of new superlattice states generated by 4--wave interactions that arise when symmetry constraints rule out 3--wave resonances.Comment: The paper contains 34 pages and 53 figures and provides an extensive review of both the theoretical and experimental work peformed in this syste

Analysis and Verification of Service Interaction Protocols - A Brief Survey

Modeling and analysis of interactions among services is a crucial issue in Service-Oriented Computing. Composing Web services is a complicated task which requires techniques and tools to verify that the new system will behave correctly. In this paper, we first overview some formal models proposed in the literature to describe services. Second, we give a brief survey of verification techniques that can be used to analyse services and their interaction. Last, we focus on the realizability and conformance of choreographies.Comment: In Proceedings TAV-WEB 2010, arXiv:1009.330

Interaction of two modulational instabilities in a semiconductor resonator

The interaction of two neighboring modulational instabilities in a coherently driven semiconductor cavity is investigated. First, an asymptotic reduction of the general equations is performed in the limit of a nearly vertical input-output characteristic. Next, a normal form is derived in the limit where the two instabilities are close to one other. An infinity of branches of periodic solutions are found to emerge from the unstable portion of the homogeneous branch. These branches have a nontrivial envelope in the bifurcation diagram that can either smoothly join the two instability points or form an isolated branch of solutions

The future for Mediterranean wetlands: 50 key issues and 50 important conservation research questions

Wetlands are critically important for biodiversity and human wellbeing, but face a range of challenges. This is especially true in the Mediterranean region, where wetlands support endemic and threatened species and remain integral to human societies, but have been severely degraded in recent decades. Here, in order to raise awareness of future challenges and opportunities for Mediterranean wetlands, and to inform proactive research and management, we identified (a) 50 key issues that might affect Mediterranean wetlands between 2020 and 2050, and (b) 50 important research questions that, if answered, would have the greatest impact on the conservation of Mediterranean wetlands between 2020 and 2050. We gathered ideas through an online survey and review of recent literature. A diverse assessment panel prioritised ideas through an iterative, anonymised, Delphi-like process of scoring, voting and discussion. The prioritised issues included some that are already well known but likely to have a large impact on Mediterranean wetlands in the next 30 years (e.g. the accumulation of dams and reservoirs, plastic pollution and weak governance), and some that are currently overlooked in the context of Mediterranean wetlands (e.g. increasing desalination capacity and development of antimicrobial resistance). Questions largely focused on how best to carry out conservation interventions, or understanding the impacts of threats to inform conservation decision-making. This analysis will support research, policy and practice related to environmental conservation and sustainable development in the Mediterranean, and provides a model for similar analyses elsewhere in the world