Modeling Selective Availability of the NAVSTAR Global Positioning System

As the development of the NAVSTAR Global Positioning System (GPS) continues, there will increasingly be the need for a software centered signal model. This model must accurately generate the observed pseudorange which would typically be encountered. The observed pseudorange varies from the true geometric (slant) range due to range measurement errors. Errors in range measurement stem from a variety of hardware and environment factors. These errors are classified as either deterministic or random and, where appropriate, their models are summarized. Of particular interest is the model for Selective Availability which is derived from actual GPS data. The procedure for the determination of this model, known as the System Identification Theory, is briefly outlined. The synthesis of these error sources into the final signal model is given along with simulation results

GPS interferometric attitude and heading determination: Initial flight test results

Attitude and heading determination using GPS interferometry is a well-understood concept. However, efforts have been concentrated mainly in the development of robust algorithms and applications for low dynamic, rigid platforms (e.g., shipboard). This paper presents results of what is believed by the authors to be the first realtime flight test of a GPS attitude and heading determination system. The system is installed in Ohio University's Douglas DC-3 research aircraft. Signals from four antennas are processed by an Ashtech 3DF 24-channel GPS receiver. Data from the receiver are sent to a microcomputer for storage and further computations. Attitude and heading data are sent to a second computer for display on a software generated artificial horizon. Demonstration of this technique proves its candidacy for augmentation of aircraft state estimation for flight control and navigation as well as for numerous other applications

On the genus Bursaphelenchus Fuchs, 1937 (Nematoda: Parasitaphelenchinae) associated with wood and insects from declining forest trees in the Czech Republic

An overview of the genus Bursaphelenchus in the Czech Republic is presented, based on a recent survey for monitoring the presence of the pinewood nematode, Bursaphelenchus xylophilus, as well as on previous reports of this genus in the country. In addition, we provide a morphological and molecular characterization of four Bursaphelenchus species (B. eremus, B. pinophilus, B. vallesianus and B. borealis) found during the monitoring programme for forest pests, conducted during 2006–2010, within the Moravian and Bohemian regions. Nematodes were extracted from over 1917 insects and 1493 wood samples collected from deciduous and coniferous trees exhibiting wilting and declining symptoms. Bursaphelenchus species were found only in 0.73% of insects and 0.47% of the total number of wood samples. Bursaphelenchus borealis and B. pinophilus dauer juveniles were found associated with the insect vectors Dryocetes autographus and Pityogenes bidentatus, respectively. While a total of seven Bursaphelenchus species are now reported from the Czech Republic, the status of B. xylophilus remains as absent

The differential polarizability of CHO cells can be used to monitor changes in metabolism

The continuous monitoring of cell growth and viability is an integral part of biopharmaceutical production. Measurements of changes in the polarizability of individual cells can identify early emerging sub-populations of apoptotic cells in a dielectrophoretic (DEP) cytometer designed at the University of Manitoba. In this instrument the trajectory of individual cells was tracked as they passed through a bank of electrodes (sensitivity: 0.1 µm; rate: 5 cells per second) designed to differentially perturb the cells according to their polarizability. This perturbation was recorded as a force index (FI), which was related to the electrical displacement of the cells. Using this principle we were able to show the changing profile of Mab-secreting CHO cells from samples taken from a bioreactor during the later stages of culture. These sub-populations could be correlated with the fluorescent markers of apoptosis analyzed in a flow cytometer with fluorescent detection (Guava). The DEP cytometer can be compared to capacitance measurements of a cell population in a bioreactor using commercially available sterilizable probes (e.g. Aber). However, these probes measure an average change in the population as opposed to the analysis of single cells, which allows greater insight into the metabolic changes of sub-populations. Cytometric analysis of single cells enables low density sub-populations to be identified that might otherwise be masked by the overall response of the whole cell population. We have extended our analysis of cultures to the induction of apoptosis by alternative means such as nutrient starvation or the addition of the anti-metabolites, oligomycin, and staurosporine. In each case, discrete cell sub-populations were identified as cells passed through the various stages of apoptosis. These sub-population could be correlated with alternative measurements by fluorescent markers, a cell population-based capacitance probe and trypan blue exclusion. In the batch and the starvation culture the early changes in the measured FI of cells correlated with the Annexin V fluorescent assay, which was associated with early phase apoptosis. For the oligomycin and staurosporine cultures changes in the FI could be correlated to modifications in the mitochondrial metabolism linked with early apoptosis for both inducers. Overall our results showed that the DEP cytometer offers a sensitive method of monitoring the metabolic state of CHO cells during a bioreactor run or following treatment with a metabolic inhibitor using single cell analysis

The oxygen binding protein, HEMOXCell(R), increases CHO cell growth and extends viability by enhancing oxygen delivery

The continuous monitoring of cell growth and viability is an integral part of biopharmaceutical production. Measurements of changes in the polarizability of individual cells can identify early emerging sub-populations of apoptotic cells in a dielectrophoretic (DEP) cytometer designed at the University of Manitoba. In this instrument the trajectory of individual cells was tracked as they passed through a bank of electrodes (sensitivity: 0.1 µm; rate: 5 cells per second) designed to differentially perturb the cells according to their polarizability. This perturbation was recorded as a force index (FI), which was related to the electrical displacement of the cells. Using this principle we were able to show the changing profile of Mab-secreting CHO cells from samples taken from a bioreactor during the later stages of culture. These sub-populations could be correlated with the fluorescent markers of apoptosis analyzed in a flow cytometer with fluorescent detection (Guava). The DEP cytometer can be compared to capacitance measurements of a cell population in a bioreactor using commercially available sterilizable probes (e.g. Aber). However, these probes measure an average change in the population as opposed to the analysis of single cells, which allows greater insight into the metabolic changes of sub-populations. Cytometric analysis of single cells enables low density sub-populations to be identified that might otherwise be masked by the overall response of the whole cell population. We have extended our analysis of cultures to the induction of apoptosis by alternative means such as nutrient starvation or the addition of the anti-metabolites, oligomycin, and staurosporine. In each case, discrete cell sub-populations were identified as cells passed through the various stages of apoptosis. These sub-population could be correlated with alternative measurements by fluorescent markers, a cell population-based capacitance probe and trypan blue exclusion. In the batch and the starvation culture the early changes in the measured FI of cells correlated with the Annexin V fluorescent assay, which was associated with early phase apoptosis. For the oligomycin and staurosporine cultures changes in the FI could be correlated to modifications in the mitochondrial metabolism linked with early apoptosis for both inducers. Overall our results showed that the DEP cytometer offers a sensitive method of monitoring the metabolic state of CHO cells during a bioreactor run or following treatment with a metabolic inhibitor using single cell analysis

Kollokationer som fraseologisk kategori set fra forskellige synsvinker

The delimitation of collocations as a category on its own can be done along different lines. The purpose of this paper is to discuss the definition and use of the term ’collocation’ from various points of view. Collocations differ from free word combinations on one hand and from idioms on the other, having two characteristic features: a certain degree of meaning compositionality and a certain degree of formal, structural and lexical fixedness. These features appear in several combinations which form the basis of different classifications. First, criteria and classifications are discussed; second, the use of the term in lexicographic theory and corpus linguistics is analyzed. The discussion is illustrated by a few examples of lexicographic representation in Danish dictionaries. Finally, an outline of various descriptive approaches with their focus on particular features is presented

College student alcohol use: a validation of naturally occurring quantity and frequency of alcohol use subgroups and cluster analytically derived typologies for males and females

This investigation sought to identify, characterize, and contrast alcohol use subgroups, by gender, in a college sample. Subgroups were formed by (1) alcohol consumption patterns and (2) cluster analytic methods. The resulting subgroups were externally validated with instruments selected from various domains;In general, univariate and multivariate analyses evidenced the existence of empirically and conceptually distinct subgroups for the majority of cluster derived subgroups. The quantity-frequency of alcohol use subgroups exhibited overall Minnesota Multiphasic Personality Inventory (MMPI) and Personality Research Form (PRF) empirical differences but were conceptually homogeneous. Relative differences were exhibited in individual scale elevations and, in some instances, did not reflect behavioral or cognitive uniqueness. However, many PRF derived clusters did manifest conceptually distinct MMPI profiles;The vast majority of all subgroups were characterized by MMPI Ma and Sc scale elevations. Female PRF derived clusters exhibited additional MMPI F and PD scale elevations with some male quantity-frequency of alcohol use subgroups evidencing F scale elevations;Overall, PRF subgroup commonalities were found for the Infrequency and Understanding scales. Further analysis revealed a wide scatter of PRF commonalities and uniqueness reflecting statistical and conceptual subgroup distinctions for the PRF derived clusters. The majority of quantity-frequency of alcohol use subgroup distinctions were subtle and of little utility in distinguishing subgroups;Compared with previous studies, male alcohol consumption patterns increased slightly, from an already elevated level, while college females demonstrated a dramatic upswing in their drinking habits. There was an overall increase in college student moderately heavy and heavy drinking. Furthermore, college students acknowledge an alarming number of alcohol related behavioral problems

Choledocholithiasis Causing Obstructive Jaundice 52 Years After Cholecystectomy

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111145/1/j.1532-5415.1995.tb07416.x.pd

The Pine Wood Nematode: a personal view

The first report of the disease (“pine wilt disease”) associated with the pinewood nematode, goes back to 1905, when Yano reported an unusual decline of pines from Nagasaki. For a long time thereafter, the cause of he disease was sought, but without success. Because of the large number of insect species that were usually seen around and on infected trees, it had always been assumed that the causal agent would prove to be one of these. However, in 1971, Kiyohara and Tokushike found a nematode of the genus Bursaphelenchus in infected trees. The nematode found was multiplied on fungal culture, inoculated into healthy trees and then re-isolated from the resulting wilted trees. The subsequent published reports were impressive: this Bursaphelenchus species could kill fully-grown trees within a few months in the warmer areas of Japan, and could destroy complete forests of susceptible pine species within a few years. Pinus densiflora, P. thunbergii und P. luchuensis were particularly affected. In 1972, Mamiya and Kiyohara described the new species of nematode extracted from the wood of diseased pines; it was a named Bursaphelenchus lignicolus. Since 1975, the species has spread to the north of Japan, with the exception of the most northerly prefectures. In 1977, the loss of wood in the west of the country reached 80%. Probably as a result of unusually high summer temperatures and reduced rainfall in the years 1978 and 1979, the losses were more than 2 million m3 per year. From the beginning, B. lignicolus was always considered by Japanese scientists to be an exotic pest. But where did it come from? That this nematode could also cause damage in the USA became clear in 1979 when B. lignicolus was isolated in great numbers from wood of a 39 year-old pine tree (Pinus nigra) in Missouri which had suddenly died after the colour of its needles changed to a reddish-brown colour (Dropkin und Foudin, 2 1979). In 1981, B. lignicolus was synonymised by Nickle et al. with B. xylophilus which had been found for the first time in the USA as far back as 1929, and reported by Steiner and Buhrer in 1934. It had originally been named Aphelenchoides xylophilus, the wood-inhabiting Aphelenchoides but was recognised by Nickle, in 1970,to belong in the genus Bursaphelenchus. Its common name in the USA was the "pine wood nematode" (PWN. After its detection in Missouri, it became known that B. xylophilus was widespread throughout the USA and Canada. It occurred there on native species of conifers where, as a rule, it did not show the symptoms of pine wilt disease unless susceptible species were stressed eg., by high temperature. This fact was an illuminating piece of evidence that North America could be the homeland of PWN. Dwinell (1993) later reported the presence of B. xylophilus in Mexico. The main vector of the PWN in Japan was shown to be the long-horned beetle Monochamus alternatus, belonging to the family Cerambycidae. This beetle lays its eggs in dead or dying trees where the developing larvae then feed in the cambium layer. It was already known in Japan in the 19th century but in the 1930s, it was said to be present in most areas of Japan, but was generally uncommon. However, with the spread of the pine wilt disease, and the resulting increase of weakened trees that could act as breeding sites for beetles, the populations of Monochamus spp. increased significantly In North America, other Monochamus species transmit PWN, and the main vector is M. carolinensis. In Japan, there are also other, less efficient vectors in the genus Monochamus. Possibly, all Monochamus species that breed in conifers can transmit the PWN. The occasional transmission by less efficient species of Monochamus or by some of the many other beetle genera in the bark or wood is of little significance. In Europe, M. galloprovincialis and M. sutor transmits the closely related species B. mucronatus. Some speculate that these two insect species are “standing by” and waiting for the arrival of B. xylophilus. In 1982, the nematode was detected and China. It was first found in dead pines near the Zhongshan Monument of Nanjing (CHENG et. al. 1983); 265 trees were then killed by pine wilt disease. Despite great efforts at eradication in China, the nematode spread further and pine wilt disease has been 3 reported from parts of the provinces of Jiangsu, Anhui, Guangdong, Shandong, Zhejiang and Hubei (YANG, 2003). In 1986, the spread of the PWN to Taiwan was discovered and in 1989, the nematode was reported to be present in the Republic of Korea where it had first been detected in Pinus thunbergii and P. densiflora. It was though to have been introduced with packing material from Japan. PWN was advancing. In 1984, B. xylophilus was found in wood chips imported into Finland from the USA and Canada, and this was the impetus to establish phytosanitary measures to prevent any possible spread into Europe. Finland prohibited the import of coniferous wood chips from these sources, and the other Nordic countries soon followed suit. EPPO (the European and Mediterranean Plant Protection Organization) made a recommendation to its member countries in 1986 to refuse wood imports from infested countries. With its Directive of 1989 (77/93 EEC), the European Community (later called the European Union or EU) recognised the potential danger of B. xylophilus for European forests and imposed restrictions on imports into the Europe. PWN was placed on the quarantine list of the EU and also of other European countries. Later, in 1991, a dispensation was allowed by the Commission of the EU(92/13 EEC) for coniferous wood from North America provided that certain specified requirements were fulfilled that would prevent introduction