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The emergence of high-definition television (HDTV), IPTV, and video-on-demand services, along with the advent of peer-to-peer video applications, has placed a strain on the bandwidth requirements and operational efficiency of [...]

The earliest figural art known from Greece is dated to the Neolithic period (ca. 8,5 to 5thousandyears ago). A recent study of the petroglyphs at Asphendou Cave on the island of Crete, however, suggests that such art has a much longer history in the Aegean basin. First published over forty years ago, the debate concerning the petroglyphs' age has lain dormant for decades. In light of technological advances in digital imaging and recent archaeological and palaeontological discoveries on the island we re-assess the dating of the petroglyphs and prove that some were made in the Late Pleistocene, or Upper Palaeolithic. Comparison of the iconography to fossil data demonstrates that an extinct endemic deer (Candiacervus) is represented at Asphendou Cave. This is the earliest figural art yet discovered in Greece.

Excavation at the Mesolithic site of Damnoni in southwest Crete generated nine tools made of obsidian, a raw material foreign to the island. This study characterises these artefacts' raw material via elemental analyses and their techno-typological nature. These data when located within a broader consideration of the larger Damnoni chipped stone assemblage and the consumption of obsidian at other Mesolithic sites of the larger region enables us to further develop our understanding of maritime activity and hunter-gatherer interaction in the Early Holocene Aegean. Using energy-dispersive X-ray fluorescence spectroscopy the obsidian is shown to be Melian, primarily from Sta Nychia, in keeping with Aegean Mesolithic procurement habits more generally. The artefacts were accessed in the form of ready-made tools, likely via exchange with intermediaries, the procurement of such exotic pieces conceivably serving to both maintain and reproduce social relations and cultural traditions at distance.

Industrial areas like manufacturing, logistics and power systems require highly flexible and adaptable control solutions in order to fulfill future requirements. An industrial automation system has to provide technologies, concepts and mechanisms allowing the adaption of control logic during operation. Proper engineering approaches as well as execution environments with dynamic reconfiguration capabilities are needed to turn this vision into reality. This article provides an overview of applying the IEC 61499 reference model for distributed automation as basis for a standard-compliant reconfigurable method in industrial environments. It covers the modeling and engineering of reconfiguration applications and their execution on distributed embedded controllers using IEC 61499. This approach significantly increases engineering efficiency and reuse in component-based design of industrial automation and control applications. A special focus of this contribution is the discussion of implemented industrial use cases from the manufacturing, robotics and power systems domain.

Current trends such as shorter product lifecycles, reduced time-to-market and mass-customisation require new paradigms and approaches for production lines and machines. In the long term, production and manufacturing companies will only be able to survive in the face of increasing globalisation if they can react flexibly and quickly to changing customer and market demands. New paradigms and approaches are waiting to fulfil these requirements, but their implementation requires completely new technologies. Reconfiguration, both at machine (physical) and control technology (logical) level is a promising candidate to achieve the flexibility required by these paradigms by technical means. This makes a shift from centrally controlled, highly interlinked, and often tightly interlocked production systems to distributed, modular, collaborative components essential. This paper describes the distributed control concept for a 6-DOF reconfigurable robot arm based on the IEC 61499 reference model as a demonstration platform for reconfigurable approaches.

In order to reveal syncytia within the visceral musculature of Drosophila melanogaster, we have combined the GAL4/UAS system with the single-cell transplantation technique. After transplantation of single cells from UAS-GFP donor embryos into ubiquitously GAL4-expressing recipients, the expression of the reporter gene was exclusively activated in syncytia containing both donor- and recipient-derived nuclei. In the first trial, we tested the system in the larval somatic musculature, which is already known to consist of syncytia. By this means we could show that most of the larval somatic muscles are generated by clonally non-related cells. Moreover, using this approach we were able to detect syncytia within the visceral musculature – a tissue that has previously been described as consisting of mononuclear cells. Both the longitudinal visceral musculature of the midgut and the circular musculature of the hindgut consist of syncytia and persist through metamorphosis. This novel application of the transplantation technique might be a powerful tool to trace syncytia in any organism using the GAL4/UAS system.

This paper describes the development of fiber optics technology—an essential element of the telecommunications revolution—and reviews the remarkable progress in fiber design and fabrication, optical amplifiers, UV‐induced fiber gratings, novel microstructured optical fibers, and integrated optics. The paper also explores the limits of optical fiber channel capacity and considers the future of optical communications.

A four-port bandpass filter is demonstrated with good performance by use of UV-induced Bragg gratings in P-doped channel waveguides without UV trimming. The simple, single-step fabrication procedure is experimentally and theoretically analyzed, and tolerances are calculated for achieving practical wavelength-division-multiplexed communication system performance.

Despite the great therapeutic advances, the control of hypertension in populations is far below the achievable level, even in populations with highly developed health care. By the end of the 1980's, in selected European centres, 18-34% of cases of hypertension were undetected, and among those previously known, 22-38% were untreated. The cooperative WHO/WHL Hypertension Management Audit Project aimed at assessing some of the impediments to better control of hypertension. The concepts and attitudes of 2,215 physicians were surveyed. In various centres and at various patient ages, 25-45% of physicians would not start drug treatment below 100 mm Hg. When inquiring into the perceived reasons why hypertension had not been detected earlier, among other reasons, physicians tended to incriminate their workload, while patients often felt that there was a lack of interest on the doctor's part to take a blood pressure reading. In general, patient satisfaction seemed suboptimal. Physicians' sources of information were varied; neither WHO, nor ISH or WHL seemed to play an important role in informing the physicians.

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Surface studies of a Middle Neolithic site near Nemea have produced pottery, chipped stone, and other finds which can be used to investigate economic and social links with contemporary settlements in the northeast Peloponnesos. Discovery of the site by survey and its subsequent archaeological and geological exploration exemplify the methods developed by the Nemea Valley Archaeological Project to examine terrain in which large quantities of artifacts of many different dates are regularly found to be widely dispersed in the landscape. Examination of the extent and total distribution of Neolithic finds in the Nemea area provides a perspective on changes in settlement within the Neolithic period and in the subsequent Early Bronze Age.

The relationship between serum total cholesterol, measured at randomization, and mortality was investigated in 822 patients, who were followed for an average of 3.1 years in a double-blind trial, conducted by the European Working Party on High Blood Pressure in the Elderly. Serum cholesterol, measured at randomization, was 0.54 mmol/l higher in women than in men, and declined with increasing age in both men (0.028 mmol/l per year) and women (0.036 mmol/l per year). During follow-up on randomized treatment, cholesterol fell by a similar amount with placebo (0.11 mmol/l per year) and with active treatment (0.14 mmol/l per year). Active treatment consisted of hydrochlorothiazide (25-50 mg/day) plus triamterene (50-100 mg/day) with the addition of oc-methyldopa (0.5—2.0 g/day) in one-third of the patients. Serum total cholesterol, measured at randomization, was independently and inversely correlated with total (P0.03), non-cardiovascular (P0.03) and cancer (P0.04) mortality during follow-up on double-blind treatment. Total and non-cardiovascular mortality were also negatively correlated with haemoglobin and body weight at randomization.

Experimental results are presented that show that diffraction off a surface-relief reflection grating can be used to extend the FWHM input coupling efficiency versus the coupled-light wavelength of a grating coupler from 0.7 to 17 nm. Use of a surface-relief reflection grating allows high diffraction efficiency over a wide wavelength range. Dispersion-matching calculations are included that illustrate that for certain output coupling applications the FWHM can be extended to 33 nm. Analysis shows that for input-coupling applications the lateral beam shift resulting from angular dispersion may be the limiting factor for wavelength compensation.

An integrated optic grating-coupler-based optical recording head that contains fewer components and is easier to align than a conventional bulk-optics-based optical head is presented. Exemplary rf signals, radial tracking, and focus error signals obtained with the head are presented. The integration of the grating head on a single coupler on a single substrate is proposed, using a grating to tapered film waveguide.

A tapered waveguide film was deposited on a substrate with a grating structure resulting in a hybrid thin-film waveguide coupler that could be designed for a broader or narrower acceptance for wavelength or incidence angle. The optimized couplers were designed and fabricated. The couplers were found to be as efficient as traditional grating couplers but with much broader acceptance. The maximum broadening was calculated to be a coupling FWHM of 2° (or 12 nm) and was confirmed experimentally. This is 4.3 times the acceptance of an identical untapered structure.

Photographic film was used to measure low intensities of guided light scattered from three different thin-film optical waveguides. The technique is shown to permit measurement of optical loss down to 0.07 dB/cm. The method involves the taking of a photograph of a guided light beam (λ = 632.8 nm) and the use of a microdensitometer to measure the two-dimensional scattered intensity profile. The sensitivity of the photographic film permits the measurement of low light levels, and the beam profile information permits the evaluation of the uniform scattering assumption. The technique can be adapted to channel waveguide loss by using high-definition photographic film. Additionally, the use of infrared-sensitive film can permit the technique to measure loss in the infrared.

Corning 7059 glass thin film waveguides prepared by rf sputtering and vapor deposition were annealed with a CO_2 laser at various powers and scan velocities. Some reduction in optical loss was observed after laser annealing of the films. The results show a reduction in optical loss with the number of laser scans. Optical profilometer measurements indicated no change in surface roughness after laser annealing. RBS analysis of laser annealed samples show no change in elemental composition. We discuss possible optical loss reduction mechanisms and present data on the marking of thin films when annealing is done at higher CO_2 laser powers.

Dual, independently addressable thin-film resistive heaters fabricated in a multilayer geometry on the surface of an optical fiber provide a new, flexible means for thermally tuning the properties of intracore gratings. In particular, control of the current that is applied to each of these heaters permits the chirp and the central wavelength of the grating to be adjusted independently. The designs and simple fabrication procedures for these types of device, the important physics of heat flow in them, and a tunable add–drop filter that demonstrates essential aspects of their operation are described.

Aldosterone(A) binding sites have been demonstrated in human mononuclear leucocytes(HML).The measurement of the mineralocorticoid binding capacity of these receptors could be a valuable tool to assess states of mineralocorticoid insensitivity in humans.We here present data obtained in 2 sibs with PH and their parents. The 8 y old girl was diagnosed in infancy after a severe salt-losing crisis. Plsma renin activity(PRA) and A were elevated. In the 2 y old brother the diagnosis was suspected when hyponatraemia and hyperkalaemia occured in the first week of life. At this time PRA and A were normal but became elevated at 3months of age. Both children receive oral sodium supplementation, the dosage needed to normalize the sodium balance in the girl is considerably higher than in the younger brother. The parents show no signs of sodium imbalance.When measuring the A binding in HML we found no binding sites in the girl. In the boy, there were 62 receptors/cell (r/c) as compared to 170±29 r/c in normal children. The binding sites in the parents were within the normal adult range. These results are strong evidence that the A insensivity in PH is due to a deficiency of mineralocorticoid receptors. It may be speculated that this deficiency is also present in other mineralocorticoid target organs in particular in the kidney. The existence of a small amount of receptor in the boy may explain the more favorable course in this child.