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Multispectral (MS) and hyperspectral (HS) sensors can facilitate target or anomaly detection in clutter since natural clutter and man-made objects diff er in the energy they radiate across the electromagnetic spectrum. Previous research in anomaly detection has formulated two popular algorithms: those based on Gauss-Markov Random Fields (GMRF) and the so-called RX-detector. Performance of these algorithms is dependent on a number of issues including spatial resolution, spectral correlation between the imaging bands, clutter/target model accuracy and the acquired data's signal-to-noise ratio (SNR). This paper provides a comparison study of the anomaly detection performance of the RXdetector and the GMRF-based algorithm using: (1) 4m MS imagery acquired f rom the IKONOS satellite and (2) pansharpened 1m MS imagery created by fusing the 4m MS and the associated 1m panchromatic image sets. The study will be based on the detection performance for stationary and slow moving targets selected f rom imagery acquired during training exercises at Canadian Forces Base (CFB) Petawawa and CFB Wainwright, Canada.

For the past four years, the Architectural Sciences Division of Public Works Canada (PWC), under the direction of Mr. Peter A. D. Mill, has been developing techniques and procedures for building enclosure evaluations. During the winter of 1980 - 1981, the Architectural Sciences Division undertook a series of wall evaluations of fifty-three federally owned buildings. Thirty-three buildings were surveyed in the Western Region (Manitoba, Saskatchewan and Alberta) and twenty buildings in St. John's, Newfoundland (Atlantic Region).* A combination of aerial surveys and exterior and interior ground surveys were conducted by both PWC staff and private sector consultants.

Nowadays, there is a growing interest in extending the service life of wood and wood products by applying natural substances that are harmless to humans and the environment. In this paper, propolis was used as an eco-friendly wood preservative. The aim of this study was to determine the resistance of Scots pine wood treated with the propolis extract against brown-rot fungus Coniophora puteana. The wood biodegradation was assessed by gravimetric method, as well as by the analysis of ergosterol concentration in decayed wood and by the determination of changes in the wood structure by means of Fourier transform infrared spectroscopy. The results indicated that the impregnation of wood with propolis extract above 12% concentration limited fungal decay. The mass loss of wood treated with 18.9% propolis extract was 2.3% and was over 21 times lower than that for untreated wood. The analysis of ergosterol content and the changes in wood structure also confirmed that the propolis extract above 12% concentration protected wood against decay caused by C. puteana. Moreover, the propolis extract used in wood impregnation was rich in phenolic compounds, mainly chrysin, pinocembrin and galangin, which possess antimicrobial activity. The obtained results indicate that the extract of Polish propolis can be a promising natural wood preservative, safe for humans and the natural environment.

This article discusses a number of outcome measures suitable for use by physiotherapists working with patients with rheumatoid arthritis. Both objective and patient-reported measures are included, which together provide a comprehensive evaluation of the disease.

ABSTRACTElectrical resistivity imaging has been successfully used to monitor near‐surface hydrologic processes but use of standard measurement arrays may not provide the greatest data sensitivity to the imaged region. We present a method of experimental design based on the concept of informed imaging for creating an electrical resistivity imaging experiment to monitor flow beneath a recharge pond. Informed imaging is the integration of all available data about a site into the acquisition, inversion and interpretation of electrical resistivity data. Informed experimental design uses all available information to develop an a priori model of the subsurface conductivity structure that guides the selection of measurement arrays for an electrical resistivity imaging experiment given spatial and temporal constraints on the acquisition. Selection of arrays focuses on maximizing the amount of unique information acquired with each source pair. We apply the method to the selection of arrays for imaging the top 5 m of the subsurface beneath a recharge pond in Northern California, which is part of an aquifer storage and recovery project. Decreasing infiltration rates over time reduce the effectiveness of the recharge pond. We seek to monitor infiltration processes at the contact between a fines‐rich sand layer and coarser sand layer in an effort to understand the hydrologic controls on infiltration. The performance of the arrays selected using informed experimental design relative to two standard arrays (Wenner and dipole‐dipole) is validated on two synthetic subsurface conductivity models, which are representative of conductivity structures that may arise during an infiltration event. Performance is evaluated in terms of a singular value decomposition of the sensitivity matrix produced by the three types of arrays, as well as a measure of the region of investigation. Results demonstrate that arrays selected using informed experimental design provide independent information about the imaged region and are robust in the presence of noise, improving the ability to image changes in a conductivity structure that result from infiltration processes.

A test equipment was developed, which allows for real time observation of the deformation behaviour of wood cellular structure under a compression load applied in radial direction. Compression tests were performed on jack pine (Pinus banksians) and balsam poplar (Populus balsamifera) specimens to explore the relationship between the yield stress and the first failure occurring in wood cell layers during radial compression. The microstructural changes for P. banksians and P. balsamifera wood below and above the yield point were analyzed. The study results showed that for P. banksians the first failure of wood cells occurred at the first earlywood layer, while for P. balsamifera it occurred at the layer with the largest vessels. The first failure of wood cell layer for each species tested was found to correspond to the yield point on the stress-strain curve. A new method of determining the yield stress for wood specimens under radial compression was developed.

AbstractAn 84 year old male with a previous history of immune thrombotic thrombocytopenic purpura (iTTP) received the first dose of COVID19 mRNA vaccine (Pfizer-Biontech). Seven days later he was diagnosed with iTTP relapse. He received in-patient treatment with therapeutic plasma exchange, high dose steroids and rituximab and subsequently recovered. This case report highlights the need to monitor patients with iTTP following vaccination.

AbstractWater samples collected from various depths of the offshore South China and Philippine Seas were exposed to solar‐simulated radiation. Photomineralization of dissolved organic carbon (DOC) and photobleaching of chromophoric dissolved organic matter (CDOM) and its humic‐like fluorescent constituent (FDOM) were observed in all samples. Protein‐like FDOM was, however, either photo‐decomposed or photo‐produced, depending on the sample's depth. The photobleaching of CDOM and humic‐like FDOM was much faster in deep than in shallow water samples while photomineralization displayed a weaker vertical zonation. Prior‐irradiated deep water inoculated with surface‐water bacteria showed enhanced microbial DOC removal but CDOM production. Results from this study suggest that deep‐ocean CDOM and FDOM can barely survive photobleaching during one ocean mixing cycle, but photochemical turnover of the bio‐refractory deep DOC is considerably longer than its average radiocarbon age. Coupled photochemical‐microbial processes can not only remove part of the bio‐refractory deep DOM but also regenerate part of it during ocean overturning circulation.

AbstractCritical transitions in ecosystem states are often sudden and unpredictable. Consequently, there is a concerted effort to identify measurable early warning signals (EWS) for these important events. Aquatic ecosystems provide an opportunity to observe critical transitions due to their high sensitivity and rapid response times. Using palaeoecological techniques, we can measure properties of time series data to determine if critical transitions are preceded by any measurable ecosystem metrics, that is, identify EWS. Using a suite of palaeoenvironmental data spanning the last 2,400 years (diatoms, pollen, geochemistry, and charcoal influx), we assess whether a critical transition in diatom community structure was preceded by measurable EWS. Lake Vera, in the temperate rain forest of western Tasmania, Australia, has a diatom community dominated by Discostella stelligera and undergoes an abrupt compositional shift at ca. 820 cal yr BP that is concomitant with increased fire disturbance of the local vegetation. This shift is manifest as a transition from less oligotrophic acidic diatom flora (Achnanthidium minutissimum, Brachysira styriaca, and Fragilaria capucina) to more oligotrophic acidic taxa (Frustulia elongatissima, Eunotia diodon, and Gomphonema multiforme). We observe a marked increase in compositional variance and rate‐of‐change prior to this critical transition, revealing these metrics are useful EWS in this system. Interestingly, vegetation remains complacent to fire disturbance until after the shift in the diatom community. Disturbance taxa invade and the vegetation system experiences an increase in both compositional variance and rate‐of‐change. These trends imply an approaching critical transition in the vegetation and the probable collapse of the local rain forest system.