Epidemiology of encephalitis in children. A prospective multicentre study

We found 175 cases with acute encephalitis in a population of 791,712 children aged 1 month-15 years during a 2-year surveillance period in 1993-1994. The overall incidence was 10.5/100,000 child-years with the highest figure in children < 1 year of age, 18.4/100,000 child-years. The microbial diagnosis was considered proven or suggested in 110 cases (63%); varicella zoster, respiratory and enteroviruses comprised 61% of these, and adeno, Epstein Barr-, herpes simplex and rota viruses comprised 5% each. A clearcut change seems to have occurred in the aetiology of encephalitis. Mumps, measles, and rubella virus associated encephalitides have been almost eliminated. Varicella zoster, respiratory, and enteroviruses have increased in frequency and occur in younger age groups. New causes were identified, especially Chlamydia pneumoniae and HHV-6. Our data should assist in making a specific diagnosis and defining appropriate antimicrobial therapy. CONCLUSIONS: The spectrum of encephalitis in children has changed due to vaccination programs. The incidence, however, appears to be about the same due to increasing frequency of other associated old and new microbes.     

IN-LINE MEASUREMENT OF THE REFINING EFFECT-AN IMPORTANT NEW TOOL FOR USE IN THE PULP AND PAPER INDUSTRY

In the production of paper, pulp fibers are put through a refining stage. This greatly enhances the fiber characteristics and the resulting quality and properties of the paper that is being produced.

This paper outlines the various detailed processes which occur during the refining stage and what the resulting effects are on paper quality. It discusses the measurements of 'freeness' and 'drainage rate', which are used today as the primary means of measuring the'refining effect', and provides a brief evaluation of the effectiveness and limitations of these techniques.

With the Scanning Laser Microscope, one can now observe the 'refining effect' on a microscopic basis by analyzing the structure of individual fibers. In particular one can measure the changes in the mean fiber diameter and the amount of fines that are produced. These changes are measured on a statistically significant basis in real time and provide valuable information for control of the refining process itself.

This paper reports actual test results and provides a preliminary analysis of the significance of these results and how the findings could best be implemented in an actual control strategy for operating a refiner.     

Rural energy survey and scenario analysis of village energy consumption: A case study in Lao People’s Democratic Republic

In developing countries, providing all citizens an access to modern forms of energy is among the central energy policy objectives, as the linkages between modern energy services and human development are widely recognized. This paper presents in a scenario analysis of rural energy consumption, how energy services in different sectors of a village economy contribute to the achievement of the UNDP Millennium Development Goals. In a rural village in Lao People’s Democratic Republic, household energy demand and energy uses were surveyed immediately prior to the electrification of the village. Based on the situation preceding electrification of the village, the development of village electrification was studied by simulating the village energy system, accounting for all village energy uses but transportation. To study the potential development of electricity demand in the village, three scenarios were constructed using the LEAP model: “residential demand”, “income generation” and “public services”. Energy demand in each scenario was analyzed with reference to the Millennium Development Goals.     

Upconversion fluorescence resonance energy transfer in a homogeneous immunoassay for estradiol

We recently described a novel homogeneous assay principle based on upconversion fluorescence resonance energy transfer (UC-FRET), where an upconverting phosphor (UCP) is utilized as a donor. The UC-FRET has now been applied to a competitive homogeneous immunoassay for 17beta-estradiol (E2) in serum, using a small-molecular dye as an acceptor. The assay was constructed by employing an UCP coated with an E2-specific recombinant antibody Fab fragment as a donor and an E2-conjugated small-molecular dye, Oyster-556, as an acceptor. Standard curves for the assay were produced both in buffer and in male serum. Sensitized acceptor emission was measured at 600 nm under continuous laser diode excitation at 980 nm. In buffer, the IC50 value of the assay was 1 nM and in serum 3 nM. The lower limits of detection (mean of zero calibrators, 3 SD) were 0.4 and 0.9 nM, respectively. The measurable concentration range extended up to 3 nM in buffer and 9 nM in serum. Equilibrium in the assay was reached in 30 min. The novel principle of UC-FRET has unique advantages compared to present homogeneous luminescence-based methods and can enable an attractive assay system platform for clinical diagnostics and for high-throughput screening approaches.     

Barrier properties of Al2O3 and alucone coatings and nanolaminates on flexible biopolymer films

Thin atomic layer deposited (ALD) Al₂O₃ coatings are efficient barriers against gases and vapors. Al₂O₃ coatings are, however, brittle and straining them generates defects that impair barrier properties. Flexibility of ALD-grown Al₂O₃ coatings on biopolymer substrates can be improved by separating thinner Al₂O₃ layers with inorganic-organic alucone layers. The number and size of defects were smaller for these nanolaminates compared to the thick Al₂O₃ films after straining, and hence straining deteriorated the oxygen barrier properties less when applied to the laminates than when applied to the Al₂O₃ coatings.     

Estimating text legibility of a mobile display on the basis of translational vibration caused by walking

Abstract— In this study, the effect of vibration on mobile‐phone text legibility caused by walking was examined. Legibility was measured as reading performance and subjective task load when reading from a mobile‐phone display while walking on a treadmill at 1.5 km/hour, 3 km/hour, and an individually defined speed (3.9 km/hour on average). Vibration was measured on the vertical, lateral, and fore‐and‐aft axes during walking. Vibration amplitude was calculated in five different frequency bands (1, 2, 4, 8, and 16 Hz), and correlated with the legibility measures. The amplitude increased most on the vertical and fore‐and‐aft axes as a function of walking speed, and the increase was largest in the 2‐Hz frequency band. Legibility decreased concurrently with increasing vibration. The strong correlation between vibration characteristics and legibility measures suggests that vibration characteristics could, to some degree, be used in estimating small‐display legibility while walking.     

Foveal optical modulation transfer function of the human eye at various pupil sizes

We determined the foveal optical modulation transfer functions of the human eye (O) for pupil sizes of 1-8 mm by using two simple psychophysical techniques. O as a function of spatial frequency f could be described by exp[-(f/fc)n] at any pupil size in our data as well as in the data available in the literature [J. Physiol. (London) 186, 558 (1966); Opt. Acta 21, 395 (1974); Vision Res. 33, 15 (1993); J. Opt. Soc. Am. A 11, 246 (1994)]. When all these estimates of fc and n were pooled the parameters were found to depend on the pupil diameter as fc = 16.6 - 1.49p and n = exp(0.840/p - 0.318). This result indicates that at 1 mm O(f) is close to the diffraction-limited system.     

Identification of free fatty acids and some other volatile flavour compounds from Swiss cheese using on-line supercritical fluid extraction-gas chromatography

On-line supercritical CO₂ extraction - gas chromatography was applied to the isolation and identification of free fatty acids and other volatile compounds of young and ripe Swiss cheese (Emmental) produced in Finland. Extractions were carried out using a micro-cartridge at 40 °C temperature and 10 MPa pressure and the volatile fractions were analysed by DB-WAX column (polyethylene glycol phase) with flame ionization detection and mass spectrometry. The total time of analysis was less than 2.5 h. Acetic acid and propionic acid predominated over the C12–C18 acids, the longer chain fatty acids increasing in concentration during the ripening of the cheese. Due to the high proportions of fatty acids, further fractionation is required for analysis of the less abundant aroma compounds such as alcohols, carbonyls and lactones.     

Step-By-Step Atomic Insights into Structural Reordering from 2D to 3D MoS2

Vertically stacked low-dimensional heterostructures are outstanding systems both for exploring fundamental physics and creating new devices. Due to nanometer-scale building blocks, atomic scale phenomena become for them of fundamental importance, including during device operation. These can be accessed in situ in aberration-corrected scanning transmission electron microscopy (STEM) experiments. Here, the dynamics of a graphene-MoS₂ heterostructure are studied under Joule heating, where the graphene serves as a high temperature atomically thin and electron transparent “hot plate” for the MoS₂. Structural dynamics and evolution of the system are shown at the atomic scale, demonstrating that at the highest temperatures (estimated to exceed 2000 K), the continuous 2D MoS₂ transforms into separated 3D nanocrystals, initiated by sulfur vacancy creation and migration followed by formation of voids and clustering at their edges. The resulting nanocrystals exhibit predominantly hexagonal shapes with the 2H and hybrid (2H/3R, 3R/TZ) polytypes. The observed morphology of the crystals is further discussed during and after the transformation, as well as their different edge configurations and stability under electron irradiation. These observations of MoS₂ at extreme temperatures provide insights into the operation of devices based on graphene/MoS₂ heterostructures and ultimately may help device fabrication techniques to create MoS₂-based nanostructures, for example, in hydrogen evolution reaction applications.