Ergonomic procurement guidelines for visual display units as a tool for progressive change

The Swedish Telecommunications Administration (STA) has put to gether a set of requirement specifications for general purpose Visual Display Units (VDUs), and in particular for VDUs to be used in telephone directory services and similar computer supported customer services. For VDUs based on Cathode Ray Tube technology, a rationale is presented for ergonomic requirements such as dark characters on a light background, a minimum refresh rate of 70 Hz, limits for acceptable levels of electric and magnetic field strengths, and full tilt, swivel and height adjustability of the VDU. Standardized measurement methods for e.g. legibility and resolution are needed in further developing the ergonomic procure ment process.     

Stratum corneum lipid organization as observed by atomic force,confocal and two‐photon excitation fluorescence microscopy

Skin moisturization is largely a function of stratum corneum barrier capacity, which in turn is a function of the physical state and structural organization of the stratum corneum extracellular lipid matrix [ 1 - 4 ]. Three unsolved key questions with respect to this lipid matrix’ structural organization [ 3 - 6 ] are: i) whether the lipid matrix is constituted by a single‐gel phase or by co‐existing solid (crystalline or gel) domains, ii) whether a separate fluid (liquid crystalline) phase is present and iii) whether the local pH has a direct effect on the lipid matrix’ phase behaviour. Using an array of complementary visual‐related biophysical techniques (e.g. atomic force microscopy and confocal/two‐photon excitation fluorescence microscopy), it was recently shown that reconstituted membranes composed of extracted decontaminated human stratum corneum lipids do not form a fluid phase, but exclusively a single‐gel phase that segregates into co‐existing microscopic domains below pH 6 [ 7 ]. It was further shown that the role of cholesterol is related to dispersion of ceramide‐enriched domains. This effect is counteracted by the presence of free fatty acids, which mix with skin ceramides but not with cholesterol [ 8 ].     

eMaintenance—Information logistics for maintenance support

Today's providers of maintenance and in-service support related to modern aircraft are facing major challenges. A central problem with Maintenance, Repair and Overhaul (MRO) as well as support of aircraft and other complex technical systems, is to manage the ever-increasing information flow and system complexity. Both military and commercial operators need to reduce aircraft downtime and maintenance man hours. Increased manual information management has the opposite effect, inducing unnecessary cost and affect efficiency negatively. Organizations developing and providing maintenance support products and in-service support does also need to improve the capability to efficiently exploit the increasing amount of digital product information and design data provided together with hardware (HW) and software (SW) products from aircraft manufacturers, sub-system suppliers and Original Equipment Manufacturers (OEM). One way to increase aircraft availability and improve maintenance and support efficiency, is to speed up the turnaround time for scheduled and unscheduled maintenance. The ultimate goal is risk-based utilization and support, where true Condition-Based Maintenance (CBM) is integrated with current operational requirements and available resources in real-time. This aims at the elimination of all preventive scheduled maintenance based on fixed time intervals and execution of only corrective maintenance that has been predicted and turned into scheduled maintenance facilitated by proper support. To address the challenge of information logistics of digital product data and information within maintenance in-service support, providers need to adapt new methodologies and tools that enable full utilization of the advantages of digital product data and information in processes and business models, e.g., Service-Oriented Architecture (SOA). To implement such improved support solutions in a global-support environment, eMaintenance is seen as one important building block. eMaintenance includes monitoring, collection, recording and distribution of real-time system health data, maintenance-generated data as well as other decision and performance-support information to different stakeholders independent of organization or geographical location, 24 h a day, 7 days a week (24/7). eMaintenance has the potential to improve the management and performance of activities related to the whole maintenance process, and thereby improve the dependability, safety and Life Cycle Cost (LCC) of critical systems. This can be realized through a coordinated application of Information and Communication Technology (ICT) throughout the maintenance and support processes, thus integrating Built-in Test (BIT) systems, external tests at different maintenance echelons, technical information, diagnostics, prognostics and other sources of support information.The purpose of this paper is to present some results from a joint academic and aerospace industry research project, describing requirements and expectations that are important in a global-support environment, and also to propose some central components in an eMaintenance framework that integrates maintenance and ICT perspectives.     

Advance reservations for predictive service in the Internet

We extend a measurement-based admission control algorithm suggested for predictive service to provide advance reservations for guaranteed and predictive service, while retaining the attractive features of predictive service. The admission decision for advance reservations is based on information about flows that overlap in time. For flows that have not yet started, the requested values are used, and for those that have already started measurements are used. This allows us to estimate the network load accurately for the near future. To provide advance reservations we ask users to include durations in their requests. We present simulation results to show that predictive service with advance reservations provides utilization levels significantly higher than those for guaranteed service, and comparable to those for predicted service without advance reservations. Those utilization levels are reached without any preemption of other admitted flows. Finally, we discuss how to setup advance reservations over multiple hops in the Internet using resource reservation setup protocols.     

Copper smelting in Boliden’s Rönnskär works described

As much of the production as possible in Ronnskar works is handled during the day shift. This requires three times as large furnaces and casting machines as three shifts and involves a considerable outlay of capital, but the labor force is reduced approximately two thirds with production costs decreased to a corresponding degree.     

The use of a pharmacophore model for identification of novel ligands for the benzodiazepine binding site of the GABAA receptor

A Catalyst pharmacophore model has been developed for the benzodiazepine site within the GABA(A) receptor complex. The model is based on a pharmacophore model originally proposed by Cook and co-workers (Drug Des. Discovery 1995, 12, 193-248) and further developed by Kahnberg et al. (J. Med. Chem. 2002, 45, 4188-4201). The Catalyst pharmacophore model has been validated by using a series of flavonoids with varying affinities for the benzodiazepine receptor and has then been used as a search query in database searching with the aim of finding novel structures which have the possibility to be modified into novel lead compounds. Five of the hits from the database searching were purchased and their affinities for the benzodiazepine site of the GABA(A) receptor were determined. Two of the compounds displayed K(i) values below 10 microM. The substance showing highest potency in-vitro displayed an affinity of 121 nM making it an interesting compound for optimization. The false positive compounds (K(i) values >10 microM affinities) have been analysed in terms of conformational energy penalties and possibilities for hydrogen bond interactions. The analysis clearly demonstrates the need for post processing of Catalyst hits.     

Skin barrier structure, function and formation - learning from cryo-electron microscopy of vitreous, fully hydrated native human epidermis

The hydration level of the stratum corneum largely depends on the physical state and molecular organization of the stratum corneum intercellular lipid matrix. A better understanding of stratum corneum lipid organization may thus aid the development of more rational cosmetic formulations. Several experimental and theoretical problems of a fundamental character remain, however, unresolved. These are, e.g. that precise quantitative skin barrier compositional data are difficult to obtain and that in vitro experimental skin barrier models usually are of limited value because of the prevailing non-equilibrium conditions in vivo. However, new experimental methods have recently been developed, which may help to overcome some of these limitations. These are, e.g. direct electrospray ionization-mass spectrometry (ESI-MS) of intact long-chain skin ceramides and direct high-resolution cryo-transmission electron microscopy (cryo-TEM) of vitreous sections of native, fully hydrated epidermis. Here, we show that cryo-transmission electron micrographs of vitreous normal human skin often dramatically differ from those obtained by conventional electron microscopy of resin-embedded skin. Our epidermal cryo-TEM data are subsequently discussed in relation to central problems of present conceptions of skin barrier structure, function and formation.     

Nanostructure of the stratum corneum extracellular lipid matrix as observed by cryo-electron microscopy of vitreous skin sections

In recent years, high-resolution cryo-electron microscopy of vitreous skin sections has been used to visualize the formation and structure of the human stratum corneum extracellular lipid matrix. The aim of the present work was to summarize these findings. It is proposed that skin barrier formation does not take place as a 'lamellar body' fusion process, but as a lamellar 'unfolding' of a small lattice parameter lipid 'phase' with cubic-like symmetry with subsequent 'crystallization' and concomitant lamellar re-organization of the extracellular lipid matrix.     

NO2 and N2 sorption in MFI films with varying Si/Al and Na/Al ratios

MFI crystals or films with controlled thicknesses and different Si/Al ratios were grown on seeded cordierite monoliths using a clear synthesis mixture with template or a template-free gel. The materials were analyzed by scanning electron microscopy, X-ray diffraction, inductively coupled plasma-atomic emission spectrometry, X-ray photoelectron spectroscopy, thermogravimetric analysis and sorption experiments using N₂ or NO₂ adsorbates. The films were uniformly distributed over the support surface. As expected, the specific monolayer N₂ adsorption capacity (mol/g_zeolite) was constant and independent of film thickness. The specific molar NO₂ adsorption capacity was significantly lower than the specific molar monolayer N₂ adsorption capacity, indicating that NO₂ is adsorbed at specific sites rather than evenly distributed in a monolayer. A number of NO₂ adsorption sites with varying strengths were observed by TPD experiments. At 30 °C, the amount of adsorbed NO₂ in the MFI films increased with increasing Al and Na content as opposed to the N₂ adsorption capacity, which was independent of these parameters. At 200 °C, the adsorbed amount of NO₂ was lower than at 30 °C and apparently independent on Al concentration in the Na-MFI films. These results indicate that different mechanisms are involved in NO₂ adsorption. NO₂ may adsorb weakly on Na⁺ cations and also react with silanol groups and residual water in the zeolite, the latter two results in more strongly bound species. Upon NO₂ adsorption, formation of NO was observed. This work represents the first systematic study of the effects of Al and Na content on NO₂ adsorption in MFI films.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

BACKGROUND: Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO). METHODS: General hemodynamics and regional blood flows assessed by microsphere technique (15 microns) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H2O end-expiratory pressure (CPPV8) before and after intravenous administration of propanolol (0.3 mg.kg-1 followed by 0.15 mg.kg-1.h-1, n = 8) or verapamil (0.1 mg.kg-1 followed by 0.3 mg.kg-1.h-1, n = 8). RESULTS: CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase. CONCLUSIONS: The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.