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The specific conical shape of the axicon makes them well suited for the generation of so-called Bessel beams. We present here a technological micro-glass blowing platform developed for miniaturization of micro-optical components. This employs the glass-blowing process, silicon micromachining and heterogeneous bonding. Here, we focus on the unconventional fabrication methods of micro-optical components in borosilicate glass. As an example, an original concept of a micro-machined micro-axicons for generation of Bessel beams is demonstrated and experimentally validated. more...

As intracardiac signal amplitudes fluctuate due to patient activity, drug intake, and other factors, it is imperative that an adequate sensing safety margin in an implanted pacemaker be used to compensate. We studied an investigational autosensing feature that automatically adjusts the device's sensitivity. Data were collected from 55 patients, with Intermedics model 292-03 or 294-03 pacemakers, upon inclusion of the study (Visit 1); 1 month postinclusion (Visit 2); 1 month, 1 day postinclusion (Visit 3); then 1 month, 2 days postinclusion (Visit 4). Atrial (N = 45) and/or ventricular (N = 54) thresholds were assessed at each visit; during Visit 2, myopotential tests were performed at two sensitivity settings. Autosensing was activated following Visit 1, then programmed on randomly at Visit 2 or Visit 3. From Visit 2-Visit 4, patients were monitored during daily activities (D), exercise (E), and sleep (S) with 24-hour Holter. With Autosensing on, atrial undersensing episodes were D = 33 (P > 0.2), and S = 28 (p 0.5). Ventricular oversensing episodes were S = 2; atrial oversensing episodes were S = 34 (p > 0.5), D = 2, and E = 3. Comparing Autosensing adjusted sensitivity with the recommended 2:1 safety margin, 4 patients (p = 0.15) experienced atrial myopotential oversensing, and 2 patients (p = 0.15) ventricular. No unanticipated clinical events occurred. Compared with the recommended 2:1 sensing safety margin, the Autosensing feature performed equal to manual programming in preventing episodes of under/oversensing, and was better for atrial undersensing during sleep. Autosensing obviates the need for periodic reprogramming of a fixed sensitivity value. more...

The large bandgap of SiC makes the recombination mechanism the main process in determining the forward current in a large range of temperature. We have added the Poole-Frenkel effect to the conventional Shockley-Read-Hall (SRH) term of the numerical device simulator MEDICI. This paper shows the influence of this effect on SiC. > more...

The ASDEX Upgrade programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. After the finalization of the tungsten coating of the plasma facing components, the re-availability of all flywheel-generators allowed high-power operation with up to 20 MW heating power at I p up to 1.2 MA. Implementation of alternative ECRH schemes (140 GHz O2- and X3-mode) facilitated central heating above n e = 1.2 × 1020 m−3 and low q 95 operation at B t = 1.8 T. Central O2-mode heating was successfully used in high P/R discharges with 20 MW total heating power and divertor load control with nitrogen seeding. Improved energy confinement is obtained with nitrogen seeding both for type-I and type-III ELMy conditions. The main contributor is increased plasma temperature, no significant changes in the density profile have been observed. This behaviour may be explained by higher pedestal temperatures caused by ion dilution in combination with a pressure limited pedestal and hollow nitrogen profiles. Core particle transport simulations with gyrokinetic calculations have been benchmarked by dedicated discharges using variations of the ECRH deposition location. The reaction of normalized electron density gradients to variations of temperature gradients and the T e/T i ratio could be well reproduced. Doppler reflectometry studies at the L–H transition allowed the disentanglement of the interplay between the oscillatory geodesic acoustic modes, turbulent fluctuations and the mean equilibrium E × B flow in the edge negative E r well region just inside the separatrix. Improved pedestal diagnostics revealed also a refined picture of the pedestal transport in the fully developed H-mode type-I ELM cycle. Impurity ion transport turned out to be neoclassical in between ELMs. Electron and energy transport remain anomalous, but exhibit different recovery time scales after an ELM. After recovery of the pre-ELM profiles, strong fluctuations develop in the gradients of n e and T e. The occurrence of the next ELM cannot be explained by the local current diffusion time scale, since this turns out to be too short. Fast ion losses induced by shear Alfvén eigenmodes have been investigated by time-resolved energy and pitch angle measurements. This allowed the separation of the convective and diffusive loss mechanisms. more...

Detailed venom reservoir and venom gland intima morphology has been investigated in reprsentatives of 84 genera and 10 subfamilies of Braconidae with particular reference to the Doryctinac, basal cyclostomes and related groups including the Opiinae, Alysiinae and Rogadinae sens. lat. Several new phylogenetically significant characters are described and illustrated. Extcnsivc secretory ductules on the primary venom duct is suggested as a synapomorphy for the subfamilies Braconinac, Doryctinae, Opiinae, Alysiinae and Gnamptodontinae. The presence of two separate venom gland insertions and their position beyond the spiral sculpture of the reservoir are suggested as synapomorphies for the subfamilies Doryctinae and Ypsistocerinac. An anterior, weakly sclerotized, probably glandular. expansion of the reservoir characterizes the Histeromerinae and Rhyssalinae and also the enigmatic genera Thoracoplites Fischer and Doryctomorpha Ashmead which are hcre transferred to the Rhyssalinae. Within the Doryctinac, venom reservoir morphology suggests three generic groups, one comprising the genera of the Odontohraconini and possibly also the genera Acanthodoryctes, Binareu and Monarea, all of which have an essentially undivided reservoir with extremely fine and uniform spiral sculpture. the second comprising the genera Doryctophasmus, Euscelinus, Gildoria, Halycea and Schlettereriella, which share horn-like processes at the base of the venom duct insertions, and a third including Acrophasmus. Dendro- soter, Heterospilus, Megaloproctus, Rutheia, Paraspathius, Schlettereriella. Spathius and Syngaster based on the presence of two markedly different densities of annulation of the reservoir. The degree to which external and other characters support these groups is discusscd. more...

The role of intention in guiding the behavior of goal-directed systems is a problem that continues to challenge behavioral science. While it is generally agreed that intentional systems must be consistent with the laws of physics, there are many obvious differences between inanimate, physical systems and sentient, intentional systems. This suggests that there must be constraints over and above those of physics that govern goal-directed behavior. In this paper it is suggested that generic properties of self-organizing mechanisms may play a central role in the origin and evolution of intentional constraints. The properties of self-organizing systems are first introduced in the context of simple physical systems and then extended to a complex (biological) system. Whereas behavior of an inanimate physical system is lawfully determined by force fields, behavior of an animate biological system is lawfully specified by information fields. Biological systems are distinguished from simple physical systems in terms of their ubiquitous use of information fields as special (biological and psychological, social, etc.) boundary conditions on classical laws. Unlike classical constraints (boundary conditions), informational constraints can vary with time and state of the system. Because of the nonstationarity of the boundary conditions, the dynamic of the system can follow a complex trajectory that is organized by a set of spatially and temporally distributed equilibrium points or regions. It is suggested that this equilibrium set and the laws that govern its transformation define a minimal requirement for an intentional system. One of the benefits of such an approach is that it suggests a realist account for the origin of semantic predicates, thereby providing a basis for the development of a theory of symbolic dynamics. Therefore, the principles of self-organization provide a comprehensive basis for investigating intentional systems by suggesting how it is that intentions arise, and by providing a lawful basis for intentional behavior that reveals how organisms become and remain lawfully informed in the pursuit of their goals. more...

As intracardiac signal amplitudes fluctuate due to patient activity, drug intake, and other factors, it is imperative that an adequate sensing safety margin in an implanted pacemaker be used to compensate. We studied an investigational autosensing feature that automatically adjusts the device's sensitivity. Data were collected from 55 patients, with Intermedics model 292-03 or 294-03 pacemakers, upon inclusion of the study (Visit 1); 1 month postinclusion (Visit 2); 1 month, 1 day postinclusion (Visit 3); then 1 month, 2 days postinclusion (Visit 4). Atrial (N = 45) and/or ventricular (N = 54) thresholds were assessed at each visit; during Visit 2, myopotential tests were performed at two sensitivity settings. Autosensing was activated following Visit 1, then programmed on randomly at Visit 2 or Visit 3. From Visit 2-Visit 4, patients were monitored during daily activities (D), exercise (E), and sleep (S) with 24-hour Holter. With Autosensing on, atrial undersensing episodes were D = 33 (P0.2), and S = 28 (p0.05); ventricular undersensing episodes were D = 6 (p0.5). Ventricular oversensing episodes were S = 2; atrial oversensing episodes were S = 34 (p0.5), D = 2, and E = 3. Comparing Autosensing adjusted sensitivity with the recommended 2:1 safety margin, 4 patients (p = 0.15) experienced atrial myopotential oversensing, and 2 patients (p = 0.15) ventricular. No unanticipated clinical events occurred. Compared with the recommended 2:1 sensing safety margin, the Autosensing feature performed equal to manual programming in preventing episodes of under/oversensing, and was better for atrial undersensing during sleep. Autosensing obviates the need for periodic reprogramming of a fixed sensitivity value. more...

The clinical findings and results obtained in a group of 100 patients with bladder tumours are presented. These patients were controlled during a 5-year period, and submitted to the same patterns of investigation and treatment. The treatment instituted was cobalt therapy together with 5-fluorouracil, followed by surgical intervention. The results have been evaluated according to the outcome and survival rates obtained. more...

In our present work we inttend to apply the ultrasounds to the field of child nephrology, by using the Vidoson 635 model. The advantages brought about by this new diagnostic method, which does not exclude others, lyes in its tridimensional vision, of easy handling, the fact of not requiring previous preparation of the patient and very little risk. In this work we present images of normal kidneys, renal agenesia, renal hypoplasia, hydronephrosis, hydrocalcinosis, cystic disease and nephroblastoma, emphasizing its use in the differential diagnosis of liquid and solid renal mass. more...

Results are presented after 2 and 4 years of follow up of 20 women with urinary stress incontinence treated by endourethral injections of teflon. Good results were obtained in 6 cases, the other 14 women obtaining no benefit, and it is concluded that the method is of little effectiveness. more...