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This research work emphasizes the capability of delivering optically shaped targets through the interaction of nanosecond laser pulses with high-density gas-jet profiles, and explores proton acceleration in the near-critical density regime via magnetic vortex acceleration (MVA). Multiple blast waves (BWs) are generated by laser pulses that compress the gas-jet into near-critical steep gradient slabs of a few micrometres thickness. Geometrical alternatives for delivering the laser pulses into the gas target are explored to efficiently control the characteristics of the density profile. The shock front collisions of the generated BWs are computationally studied by 3D magnetohydrodynamic simulations. The efficiency of the proposed target shaping method for MVA is demonstrated for TW-class lasers by a particle-in-cell simulation.

The machinability of a steel workpiece through conventional and Laser-Assisted Machining (LAM) is studied by the help of the Finite Element Method (FEM). In LAM, the laser beam is applied as a heat source to ensure sufficient local heating of the workpiece at a certain distance from the cutting tool and the machinability of materials is increased since the values of the cutting forces are decreased. A thermostructural FEM model is developed to simulate the conventional and the LAM orthogonal cutting of AISI H-13 steel. The Johnson-Cook material model that takes into account the effect of plastic strain, strain rate and temperature, along with a fracture model, is used in the simulations. For varying feed rate, parametric simulations are carried out, for different test cases of the laser beam diameter and the laser heat flux. Key engineering parameters, like cutting forces, temperature distributions, Von Mises stresses and plastic strains, are compared for both cutting processes. This comparison leads to important notifications on the influence of the cutting and laser parameters to LAM. The obtained results indicate that LAM may improve the machinability of AISI H-13 steel by reducing the cutting forces to a maximum percentage of ~15%.

The current research focuses on the characterization of the produced heat affected zone when laser heats AISI H13 steel, AISI 1045 steel and Ti6Al4V alloy workpieces via finite element simulations and experimental investigation. The surface roughness designedly varies on the surface of the samples and its influence on the absorption of laser light is investigated. Experiments are conducted at 1-4 W laser power and for two scanning speeds of 2 and 100 mm/min. A 3D transient thermo-structural finite element model for a moving Gaussian laser heat source is developed to simulate the micromachining process and predict the depth and width of the heat affected zone. The Johnson-Cook material model that takes into account the effect of plastic strain, strain rate and temperature, along with a fracture model, is adapted to the simulations. A good agreement between the experimental data and the simulation results is found. The depth and width of the heat affected zone strongly depend on the laser parameters and material properties of the irradiated samples. This study constitutes the basis to the optimization and improvement of the laser assisted micromachining process parameters and provides key insights on the roughness-absorptivity relation for the three metallic materials.

It was recently demonstrated that a newly explored instability, which was named electro-thermo-mechanical (ETM) instability, was developed in the solid elastic phase in the case of an electrically exploded conductor in the skin effect mode. Here, we present new advances in the exploration of the role of the ETM instability as seed of the magneto-hydro-dynamic instabilities that are later observed in the plasma phase. Our study, through analytical calculations, simulations and experiments, demonstrates the whole evolution dynamics of the instability amplitude, from the solid to the plasma phase, including the phase transitions. It is validated that the sustained axial wavelength modes in the plasma phase lie in the range of values of those of the ETM instability developed in the solid phase. The results are of significant importance for understanding the role of the ETM instability as seeding for the later observed instabilities in the plasma phase.

A relativistic electron source based on high power laser interaction with gas jet targets has been developed at the Institute of Plasma Physics and Lasers of the Hellenic Mediterranean University. Initial measurements were conducted using the ‘Zeus’ 45 TW laser with peak intensities in the range of 1018–1019 W cm−2 interacting with a He pulsed gas jet having a 0.8 mm diameter nozzle. A significant improvement of the electron signal was measured after using an absorber to improve the laser pulse contrast from 10−10 to 10−11. A high stability quasi-mono-energetic electron beam of about 50 MeV was achieved and measured using a magnetic spectrometer for pulsed gas jet backing pressure of 12 bar. Supplementary studies using a 3 mm diameter nozzle for backing pressures in the range of 35–40 bar showed electron beam production with energies spread in the range from 50 to 150 MeV. The pulsed jet density profile was determined using interferometric techniques. Particle-in-cell simulations, at the above experimentally determined conditions, support our experimental findings.

In the dawn of innovative digital tools for communication and information exchange the civil society has apparently taken a step forward into this new direction. This paper explores the process for enhancing E-participation in environmental planning and making relevant government decision-making democratically accountable. Environmental issues are dealt in the civil society context with reflexivity that incorporates lay and local knowledge. The case study emphasizes on the BLN e.V e-participation platform “Umwelt-Beteiligung-Berlin” and discusses the extent and impact of Environmental Associations involvement in sustainable environmental planning. BLN e.V was created as a hub for all Berlins registered Nature conservation/Environment protection associations as well as citizens’ initiatives on environmental projects. The platform was developed in cooperation with the nature conservation associations recognized in Brandenburg and Lower Saxony. BLN working group is supported by volunteers in the Federal Ecological Volunteers Service (ÖBFD). The paper analyses the case study impact and concludes by discussing how the concept can be proliferated on EU, national, regional and local level and the prospects of future research.

The capability of the explicit numerical methods to simulate accurately the real cutting process is investigated in this research work. Smoothed particle hydrodynamics - SPH, classical Lagrangian finite element method - FEM and Multi-Material Arbitrary Lagrangian Eulerian - ALE methods are chosen for the modeling and simulation of the orthogonal metal cutting process of AISI H13 in LS-DYNA. The cutting tool is modeled as a rigid FEM body that incrementally penetrates into the flexible deformable workpiece. At each numerical model, the dynamic elastoplastic behavior of the workpiece material is investigated by taking into account the Johnson-Cook (J-C) constitutive strength material model. The influence of the J-C parameter values found in literature to the models is explored. The obtained numerical SPH, FEM and ALE results of the estimated cutting and thrust forces, stress, plastic strain and thermal distributions are compared with results found in the literature. This comparison, leads to valuable conclusions for the performance of the three methods, concerning the approximation accuracy, model development complexity and computational time demands. Based on these conclusions the SPH method is chosen to simulate the experimentally performed orthogonal cut of AISI 1045. The obtained SPH numerical results outline its advantages among the other explicit simulation methods.

The second and final year of the Erasmus Plus programme "Innovative Education and Training in high power laser plasmas", otherwise known as PowerLaPs, is described. The PowerLaPs programme employs an innovative paradigm in that it is a multi-centre programme where teaching takes place in five separate institutes with a range of different aims and styles of delivery. The "in class" time is limited to four weeks a year, and the programme spans two years. PowerLaPs aims to train students from across Europe in theoretical, applied, and laboratory skills relevant to the pursuit of research in laser plasma interaction physics and inertial confinement fusion (ICF). Lectures are intermingled with laboratory sessions, and continuous assessment activities. The programme, which is led by workers from the Hellenic Mediterranean University, and supported by co-workers from Queens University Belfast, the University of Bordeaux, the Czech Technical University in Prague, Ecole Polytechnique, the University of Ioannina, the University of Salamanca, and the University of York, has just finished its second and final year. Six Learning Teaching Training (LTT) activities have been held, at the Queens University Belfast, the University of Bordeaux, the Czech Technical University, the University of Salamanca, and the Institute of Plasma Physics and Lasers (CPPL) of the Hellenic Mediterranean University. The last of these institute hosted two two-week long Intensive Programmes (IPs), whilst the activities at the other four universities were each five days in length. In addition to this a "Multiplier Event" was held at the University of Ioannina, which will be briefly described. In this second year the work has concentrated upon training in both experimental diagnostics and simulation techniques appropriate to the study of Plasma Physics, High Power Laser-Matter Interactions and High Energy Density Physics. The nature of the programme will be described in detail and some metrics relating to the activities carried out will be presented. In particular this paper will focus upon the overall assessment of the programme.

The surface roughness and the evolution of its morphology of a pulsed laser irradiated aluminum workpiece, is investigated via numerical simulations and experimental measurements. A three-dimensional transient thermo-structural finite element model is developed to simulate the machining process. The developed finite element material model considers the effects of plastic strain, strain rate and temperature, along with a fracture model. For the experiments, a single laser pulse of 6 ns duration and 0.7 mJ of energy at 532 nm is employed as the heat source, and the surface roughness is measured using white light interferometry set-up and related experimental diagnostics. A step-like linear approximation is used to model the surface roughness. A satisfactory agreement between the experimental data and the simulation results is found. This preliminary study aims to contribute to a better understanding of the initial physical processes involved in pulsed laser machining considering the influence of surface roughness and is beneficial for industrial applications such as laser polishing, engraving and cutting.

The Z-pinch plasma device is a type of plasma confinement system that uses electrical current to generate a magnetic field which compresses a current-carrying wire. In a previous proof-of-principle study, we demonstrated that in the interaction of a single wire with a pulsed current, the generated Electro-Thermo-Mechanical (ETM) instability in the solid phase acts as a seeding mechanism for the later developed instabilities observed in the plasma phase. In this study, the influence of the geometrical characteristics, such as length and thickness of the load-wire, on the generation of the ETM instability are investigated. Finite element multiphysics-multiphase simulations starting from the solid state are coupled with Magneto-Hydro-Dynamics (MHD) simulations to study the solid to plasma phase transition and the matter’s dynamics. The numerical results of the wire expansion dynamics prior to plasma formation are validated by experimental results from a modified Fraunhofer diffraction diagnostic, while in the plasma phase the simulated plasma dynamics is validated by shadowgraphic and interferometric experimental results. The numerical and experimental results demonstrate a satisfactory agreement for the wire expansion dynamics and the growth rate of the developed instabilities, for varying wire thickness and length.

The Heat Affected Zone - HAZ of a laser irradiated AISI H-13 steel workpiece, is investigated via numerical simulations and experimental measurements. A three-dimensional transient thermo-structural finite element model is developed to simulate the machining process. A Gaussian laser beam is employed as the heat source. The developed finite element material model considers the effects of plastic strain, strain rate and temperature, along with a fracture model. The experiments are carried out with a laser of 1-4 W power and with a scanning speed of 100 mm/min. Thermocouple sensors are used for the temperature measurements, while the surface roughness is measured using white light interferometry and related experimental diagnostics. A parametric numerical analysis regarding the average absorptivity of the workpiece is performed and is compared to the experimental findings. The depth and width of HAZ and the induced strains are studied for the plastic and melting regimes. The influence of the surface roughness of the metal workpiece on the dynamics of HAZ is also experimentally demonstrated. The findings of this study highlight the role of the absorption coefficient and the surface roughness on the HAZ below the ablation threshold and can be applied to related laser machining processes.

1,3-ß-D-glucan (BDG) is increasingly used to diagnose invasive fungal infections (IFI), although false positive results are a concern. To evaluate the potential interaction of blood products with the BDG assay, human albumin (HA), fresh frozen plasma (FFP), undiluted platelet transfusion (UPT) and packed red blood cells (PRBC) were tested for their BDG content using two different b-D-glucan tests. UPTs tested negative, FFP, PBRC and HA tested positive for BDG. In serial dilution, BDG concentration correlated with blood product concentration. To investigate the clinical impact of blood product transfusions, we measured BDG levels before and after the transfusion in three patients (2 PRBC, 1 HA). In the patients receiving PRBC transfusions, BDG values increased from 13 and 17 pg ml(-1) to 183 and 361 pg ml(-1), the HA transfusion increased the serum level from 42 to 58 pg ml(-1). BDG concentrations measured in blood products can be used to predict false positive BDG results.

Summarization: The thermomechanical transient response of matter illuminated by nanosecond laser pulses is modeled and simulated using the Finite Element Analysis (FEA). Matter’s behavior is numerically described by a three-dimensional (3D) multiphysics, coupled thermal structural, transient FEA, experimentally validated, model. FEA offers substantial insights into the materials’ micro-mechanical behaviour providing detailed information for the spatiotemporal evolution of acoustic waves. In this computational approach the impact of the geometric characteristics of the modeled metallic films to the generation and propagation of the ultrasonic waves, in relation to temperature, is investigated. The study is expanded to the dynamic reactions of matter in the presence of surface and solid volume defects and enclosures e.g.: gaps, holes or bubbles. The transient behavior of matter in the time and the space solution domains is obtained by the FEA model and presented. Presented on: Key Engineering Materials

Nanoacoustic strains are generated in Silicon by chirped femtosecond laser pulses using thin Titanium films as transducers. We investigate the effect that the generating laser pulse chirp has on the amplitude of the induced strains, manifested as Brillouin oscillations observed in degenerate femtosecond pump-probe transient reflectivity measurements. The strain amplitude is larger when negatively chirped pulses are used, which is attributed to the more efficient conversion of laser pulse light into acoustic strain in the Titanium transducer. Our present studies clearly show that the dependence of the Brillouin amplitude and the lattice strain is a non-monotonous function of the laser chirp parameter. An optimum negative laser pulse chirp is found for which the strain amplitude is maximized. A detailed thermomechanical model satisfactorily supports the experimental findings. In such a way, it is possible to suppress or enhance the induced nanoacoustic strain amplitude, thus all-optically controlling it by at least a factor of two.

Background 1,3-β-D-Glucan (BDG) is a fungal cell wall constituent used in the diagnosis of invasive fungal infections. BDG testing, although endorsed by the European Organization for Research and Treatment of Cancer, suffers from limited specificity. False-positive results have been linked to haemodialysis membranes, blood products, antineoplastic agents and antimicrobial use. Objectives The aim of this study was to determine whether false-positive BDG results in the context of antimicrobial use are caused by BDG present in infusion solutions. Methods We obtained 35 antimicrobial drugs (30 antibiotics and 5 antifungals) and analysed their BDG content using two different assays. Results Twenty-five antimicrobials (20 antibiotics and all the tested antifungals) contained enough BDG to trigger a positive test. Depending on the substance, BDG varied between 9 and 2818 pg/mL. Conclusions A majority of the available antimicrobial substances contained BDG, potentially limiting the utility of BDG testing in the context of prior exposure to these drugs. As the cumulative effects of repeated BDG exposure are unknown, efforts to reduce contamination should be considered.

The purpose of this study is to present a national survey that was performed in Greece for the establishment of national Dose Reference Levels (DRLs) for seven common adult Computed Tomography (CT) examinations. Volumetric computed tomography dose index and dose-length product values were collected from the post-data page of 65 'modern' systems that incorporate tube current modulation. Moreover, phantom dose measurements on 26 'older' systems were performed. Finally, the effective dose to the patient from a typical acquisition during these examinations was estimated. The suggested national DRLs are generally comparable with respective published values from similar European studies, with the exception of sinuses CT, which presents significantly higher values. This fact, along with the large variation of the systems' dose values that were observed even for scanners of the same type, indicates a need for further patient protection optimisation without compromising the clinical outcome. © The Author 2014.

This study aimed at assessing the effect of previous anesthesia experience on patients' knowledge of anesthesia and the role of anesthesiologists, on what they would want to know about anesthesia and the way they would like to be informed.Questionnaires with fixed questions were distributed to consenting, consecutive surgical patients before the pre-anesthetic visit. Patients were divided into two groups: patients with previous anesthesia experience (Group A) and patients without previous anesthesia experience (Group B). The questionnaires included patients' demographics, questions related to their knowledge about the anesthesiologists' role and about their desire for information.500 questionnaires were analyzed. The majority of patients (94.2%) know that the anesthesiologist is a specialized doctor and 89.2% believe that the anesthesiologist watches over the patient throughout surgery. These results were similar in both groups. The majority of patients (98.2%) also want to meet the anesthesiologist before surgery and 78% want even more information. Only 65.6% want to be aware of all possible complications, in both groups, while 17.6% do not want to know anything about complications. In general, answers to specific questions regarding what the patients want to know about anesthesia did not differ between groups. The vast majority of patients wish to talk with the anesthesiologist before surgery.Previous anesthesia experience did not seem to influence patients' desire for meeting the anesthesiologist and seeking information. A strong desire to personally meet the anesthesiologist is expressed and patients' desire for even more information is noted.

Introduction: Little is known about the role of cytokines in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Interleukin (IL)-12 and IL-15 are the major growth and differentiation factors for Th-1 cells and IL-17 is a marker of Th-17 cell expansion and activation, a high proinflammatory new subset of T cells that induce severe autoimmunity. Patients and methods: We measured by enzyme-like immunosorbent assay serum and cerebrospinal fluid (CSF) levels of IL-15, IL-12, and IL-17 in 24 patients with CIDP and 12 patients with other non-inflammatory neurological disorders and serum levels in 16 healthy subjects. Results: We found a positive association of CSF IL-12 (P=0.012) with CIDP presence (P≤0.001). Conclusions: Our findings suggest that IL-12 may be involved as potential marker of immune activation in CIDP. The increase in its levels in CSF may be a marker of initiation of Th-1 cell-mediated immunity. © W. S. Maney & Son Ltd 2012.

Patients with Myotonic Dystrophy show an unpredictable response to several anesthetic drugs including opioids, neuromuscular blocking agents and especially reversal agents like neostigmine. We describe the case of a 40 year old patient with myotonic dystrophy who underwent laparoscopic cholecystectomy and ovarian cyst removal under general anesthesia. The authors suggest the use of the new reversal agent suggamadex, for reversing neuromuscular blockade caused by rocuronium, in patients suffering from neuromuscular disease and especially from Myotonic Dystrophy, because it rapidly and completely reverses any residual neuromuscular blockade, but also underline the increased susceptibility of these patients to opioids.

The aim of the present study was to develop a predictive model to quantify the spoilage of yoghurt with fruits. Product samples were stored at various temperatures (5-20 °C). Samples were subjected to microbiological (total viable counts, lactic acid bacteria-LAB, yeasts and moulds) and physico-chemical analysis (pH, titratable acidity and sugars). LAB was the dominant micro-flora. Yeasts population increased at all temperatures but a delay was observed during the first days of storage. Titratable acidity and pH remained almost constant at low temperatures (5 and 10 °C). However, at higher temperatures (>10 °C), an increase in titratable acidity and reduction in pH was observed. Sugar concentration (fructose, lactose and glucose) decreased during storage. A mathematical model was developed for shelf-life determination of the product. It was successfully validated at a temperature (17 °C) not used during model development. The results showed that shelf-life of this product could not be established based only on microbiological data and use of other parameters such as sensory or/and physico-chemical analysis is required. Shelf-life determination by spoilage tests is time-consuming and the need for new rapid techniques has been raised. The developed model could help dairy industries to establish shelf-life predictions on yoghurt with fruits stored under constant temperature conditions.

Thyroid hormones decrease systemic vascular resistance by directly affecting vascular smooth muscle relaxation. There is limited literature about their effect on the mechanical performance of the aortic wall. Therefore, the authors determined the influence of hyperthyroidism on the mechanical properties and histomorphological structure of the descending thoracic aorta in rats. Severe hyperthyroidism was induced in 20 male Wistar rats by administering L-thyroxine (T,) in their drinking water for 8 weeks; agematched normal euthyroid rats acted as controls. Animals were sacrificed, and the mechanical and histomorphometrical characteristics of the descending thoracic aorta were studied. The aortic wall of hyperthyroid rats was stiffer than that of euthyroid animals at the upper physiologic levels of stress or strain (p < 0.05) but less stiff at the lower physiologic and lower levels (p < 0.05). The aorta of hyperthyroid animals compared with that of euthyroid ones showed an increase of the internal and external diameters (p < 0.05), the media area (p < 0.05), the number of smooth muscle cell nuclei (p < 0.05), and the collagen density (p < 0.05) and a decrease in the elastin laminae thickness (p < 0.00 1) and elastin density (p < 0.00 1). In hyperthyroid rats, the aortic wall was stiffer at the upper physiologic and higher levels of stress and strain. These changes correlated with microstructural changes of the aortic wall. The coexistence of hyperthyroidism with disease states or clinical conditions that predispose to increased arterial pressure may be associated with increased arterial stiffness and have undesirable consequences on the mechanical performance of the thoracic aorta and hemodynamic homeostasis. These changes could lead to an increased risk for developing vascular complications.

In this prospective case-series study, a balanced anesthetic scheme of sevoflurane in nitrous oxide supplemented with remifentanil and sustained neuromuscular block was applied in nine patients scheduled for laparoscopic adrenalectomy for pheochromocytoma. Laparoscopic adrenalectomy to treat pheochromocytoma results in marked catecholamine release during pneumoperitoneum and tumor manipulation. Remifentanil infusion was adjusted to maintain systolic arterial pressure between 120-170 mmHg. Increased infusion rate of remifentanil was used (up to 3 microg/kg/min) to prevent and treat marked hemodynamic changes from catecholamine release during tumor manipulation. Hpotension after tumor removal was treated with additional colloids fluids and decreasing the remifentanil infusion rate by 25-50%.

The history of smoking and premedication did not influence the proportion of patients who had a cough response to fentanyl when administrated as first agent during induction in anesthesia.

More than 40 industrial radiography laboratories are operating in Greece using X-ray or gamma-ray sources and more than 250 workers occupationally exposed to ionising radiation in these facilities are monitored on a regular basis. This study presents the evolution of individual doses received by radiographers during the past years. The mean annual dose (MAD) of all workers as well as of exposed workers is estimated, and correlated to the types of laboratories and practices applied. The MAD of the exposed workers in industrial radiography is compared with the doses of workers in other specialties and with the doses of radiographers in other countries. Furthermore, the study attempts to propose dose constraints for the practices in industrial radiography, according to the BSS European directive and the relevant Greek radiation protection legislation. The proposed value was defined as the dose below which the annual doses of 75% of the exposed radiographers are expected to be included. © 2006 Oxford University Press.

We determine the feasibility of using the intubating laryngeal mask airway Fastrach (ILM) as a ventilatory device during emergence from anesthesia after use as an airway intubator in patients undergoing carotid endarterectomy. Thirty-five patients (ASA 2-3, 53-84 yr) were studied. Induction was with midazolam/fentanyl/etomidate and maintenance was with sevoflurane 1-2% in O2 33-50% and N2O. Neuromuscular blockade was with cisatracurium. Tracheal intubation was with a flexible lightwand via the ILM. After successful intubation, the ILM remained in the pharynx, but with the cuff deflated. After surgery, but before anesthesia was discontinued, baseline cardiovascular variables were recorded. The ILM cuff was then reinflated, the tracheal tube removed, the anesthesia breathing system connected to the ILM and anesthesia discontinued. Any changes in the cardiovascular variables greater than +/- 20% baseline values were noted from cuff reinflation to 1 minute after ILM removal. Any adverse respiratory (laryngospasm, coughing, gagging, stridor, SpO294%, end-tidal carbon dioxide45 mmHg, regurgitation/aspiration) or electrocardiographic (ST segment or rhythm changes) events were also noted. Patients were questioned about postoperative sore throat at 2 and 24 hr. ILM insertion and intubation through the ILM were successful in all patients. Adequate ventilation was achieved in all patients before intubation and after extubation. The mean (range) time taken from cuff reinflation to ILM removal was 9 (5-21) min. The rate pressure product remained within +/- 20% baseline values in all patients. There were no adverse respiratory or electrocardiographic events. There were no adverse neurological events. The surgical field was satisfactory. Postoperative sore throat occurred in 14% at 2 hr and 0% at 24 hr. We conclude that the ILM can be used as a ventilatory device for emergence from anesthesia after use as an airway intubator for carotid endarterectomy.

The aim of this study was the evaluation of the blockade of branches of ophthalmic nerve in the management of the acute attack of migraine headache localized to the ocular region. The study included 70 female patients 23-60 years old who presented to the pain clinic at our hospital with an acute attack of migraine headache localized to the ocular and retro-ocular region. A targeted history and a neurologic examination were performed in all patients to confirm the diagnosis and at the same time to rule out life-threatening neurological dysfunction. The method applied was the blockade of the supraorbital and supratrochlear nerves which are branches of the ophthalmic nerve. By the use of a fine short needle 27G the nerves were sought for until paraesthesia is obtained and then 1 ml of lignocaine 2% with adrenaline 1:200,000 was injected in every one of the three sites of the nerves. The migraine acute attack was relieved in 58/70 patients (82%), while in 12/70 patients (18%) the results were poor. The pain relief started 3-4 min after the injection and was completed in 10-15 min. Our results support that the blockade of the branches of the ophthalmic nerve seems to be a safe and effective technique in the management of the acute attack of migraine localized to the ocular and retro-ocular region.

We have evaluated the use of a prototype lighted flexible catheter using the transillumination of the light through the soft tissues of the neck, as a detector of the accidental oesophageal intubation during the tracheal intubation through the intubating laryngeal mask. Two hundred patients undergoing general anaesthesia were studied. Accidental oesophageal intubation occurred in 12 patients (6%) during the first intubating attempt and was diagnosed by noting absence of glow on the neck during the tracheal tube advancement and was confirmed by capnography. However, 11/12 (92%) of the above patients were finally intubated successfully, using the lighted flexible catheter. In one patient persistent accidental oesophageal intubation occurred and was classified as failure.

Conditions for insertion of the cuffed oropharyngeal airway (COPA) were assessed following two different dosage regimens of propofol: group I (n = 40): 1.5 mg.kg-1; group II (n = 40): 2.5 mg.kg-1. The insertion conditions were evaluated by using a scoring system (-, + and +2) of gag and cough reflexes. The necessary use of additional dosage of propofol and the duration of post-induction apnea were also recorded. There were no significant differences between the two groups in the incidence of coughing, gagging and the additional usage of induction agent. The mean (+/- SD) duration of apnea was significantly longer in the high dose group: 9 +/- 6 min vs 5 +/- 7 min (p = 0.007). Low dose of propofol combines efficient insertion conditions with decreased length of post-induction apnea.

We evaluated the efficacy of a newly developed prototype illuminated flexible catheter to facilitate tracheal intubation through the intubating laryngeal mask and compared this light-guided technique with the conventional blind tracheal intubation through the intubating laryngeal mask. The illuminated flexible catheter consists of a completely flexible thin plastic catheter, a bulb attached to its distal end, a 15-mm concentric adapter at its proximal end connected with a battery and a power switch. The device is placed into a silicone tracheal tube in such a way that the bulb protrudes from the distal end of the tracheal tube. One hundred adult patients, ASA I-III, scheduled to undergo propofol/fentanyl/atracurium anaesthesia for elective surgery were studied. All participants underwent a randomized double comparative cross over trial with respect to the tracheal intubation technique through the intubating laryngeal mask. The light guided tracheal intubation was performed as follows; the tracheal tube preloaded with the illuminated flexible catheter was inserted through the intubating laryngeal mask and by observing the glow in the neck was advanced into the trachea. Whenever resistance was felt during insertion, appropriate adjusting manoeuvres were performed. The intubating laryngeal mask was inserted successfully in all patients. The success rate for the blind and light-guided technique was 91% and 100%, respectively (P = 0.003). The mean (+/- SD) duration including appropriate intubating laryngeal mask placement and tracheal intubation, was significantly lower in the light-guided tracheal intubation technique, than with the blind tracheal intubation (31 +/- 8 s vs. 43 +/- 18 s; P0.0001). We conclude that the use of an illuminated flexible catheter carries advantages either in optimizing the intubating laryngeal mask position in the laryngopharynx or in achieving a quick and safe light-guided advancement from laryngopharynx into the trachea.

The design and construction of a pulsed plasma focus device to be used as a portable neutron source for material analysis such as explosive detection using gamma spectroscopy is presented. The device is capable of operating at a repetitive rate of a few Hz. When deuterium gas is used, up to 105 neutrons per shot are expected to be produced with a temporal pulse width of a few tens of nanoseconds. The pulsed operation of the device and its portable size are its main advantage in comparison with the existing continuous neutron sources. Parts of the device include the electrical charging unit, the capacitor bank, the spark switch (spark gap), the trigger unit and the vacuum–fuel chamber / anode–cathode. Numerical simulations are used for the simulation of the electrical characteristics of the device including the scaling of the capacitor bank energies with total current, the pinch current, and the scaling of neutron yields with energies and currents. The MCNPX code is used to simulate the moderation of the produced neutrons in a simplified geometry and subsequently, the interaction of thermal neutrons with a test target and the corresponding prompt γ-ray generation.

A review study of the developments in the field of pulsed laser-solid interaction simulation methods, for moderate laser energies, is presented. The paper is focused on the methods that numerically simulate the interactions of pulsed ns-laser with solid metal targets. Three main regimes for pulsed laser excitation, are well established, namely, the thermoelastic, melting and plasma regimes. The modelling and simulation techniques that may numerically describe these three regimes and the occurring dynamic matter responses are reviewed. Modelling efforts concerning various fields of applications of lasers are briefly discussed.

The three dimensional spatiotemporal response of thin metal films surfaces excited by nanosecond laser pulses is investigated in both the thermoelastic and the ablation regimes. An experimental laser whole-field interferometric technique allows for the direct monitoring of the dynamic deformation of a macroscopic area on the surface with ultrahigh lateral resolution. A specially developed three dimension finite element model simulates the laser-surface interaction, predicts the experimentally obtained results, and computes key parameters of matter's thermomechanical response. This method provides a powerful instrument for spatiotemporal behavior of thin-film surfaces under extreme conditions demanded for innovative applications.

The object of this work is the study of the individual film badge annual dose information of classified workers in Greece, monitored and assessed by the central dosimetry service of the Greek Atomic Energy Commission. Dose summaries were recorded and processed by the Dose Registry Information System. The statistical analysis refers to the years 1989-93 and deals with the distribution of individuals in the occupational groups, the mean annual dose, the collective dose, the distribution of the dose over the different specialities and the number of workers that have exceeded any of the established dose limits. Results concerning the annual dose summaries, demonstrate a year-by-year reduction in the mean individual dose to workers in the health sector. Conversely, exposures in the industrial sector did not show any decreasing tendency during the period under consideration.