Asymptotic stability of sampled nonlinear systems with variable sampling periods -- A bionic application Discussion

Developing Vidals and Laurents criteria for asymptotic stability of nonlinear sampled system using Liapunov function

Rlp7p is associated with 60S preribosomes, restricted to the granular component of the nucleolus, and required for pre-rRNA processing

Many analyses have examined subnucleolar structures in eukaryotic cells, but the relationship between morphological structures, pre-rRNA processing, and ribosomal particle assembly has remained unclear. Using a visual assay for export of the 60S ribosomal subunit, we isolated a ts-lethal mutation, rix9-1, which causes nucleolar accumulation of an Rpl25p-eGFP reporter construct. The mutation results in a single amino acid substitution (F(176)S) in Rlp7p, an essential nucleolar protein related to ribosomal protein Rpl7p. The rix9-1 (rlp7-1) mutation blocks the late pre-RNA cleavage at site C(2) in ITS2, which separates the precursors to the 5.8S and 25S rRNAs. Consistent with this, synthesis of the mature 5.8S and 25S rRNAs was blocked in the rlp7-1 strain at nonpermissive temperature, whereas 18S rRNA synthesis continued. Moreover, pre-rRNA containing ITS2 accumulates in the nucleolus of rix9-1 cells as revealed by in situ hybridization. Finally, tagged Rlp7p was shown to associate with a pre-60S particle, and fluorescence microscopy and immuno-EM localized Rlp7p to a subregion of the nucleolus, which could be the granular component (GC). All together, these data suggest that pre-rRNA cleavage at site C(2) specifically requires Rlp7p and occurs within pre-60S particles located in the GC region of the nucleolus

Hydrothermal synthesis of lithium silicate (Li2SiO3) from waste glass: a preliminary study

Current environmental directives to conserve resources and to divert waste streams have generated significant interest in mineral recycling. In this respect, this preliminary study has demonstrated that lithium metasilicate can be prepared by hydrothermal reaction between waste container glass and lithium hydroxide solutions at 100 °C. Minor proportions of calcium hydroxide, calcite, lithium carbonate and tobermorite were also produced during the reaction. Percentage crystallinity and proportion of lithium metasilicate in the reaction product were found to increase as functions of lithium hydroxide concentration (between 1 and 4 M). This research has also shown that the lithium metasilicate phase can take up 6.4 mmol/g of Zn2+ ions after 24 h during batch sorption. Further work to optimise the yield and to appraise the antimicrobial properties of Zn2+-bearing lithium metasilicate is now warranted

Motion-base simulator study of control of an externally blown flap STOL transport aircraft after failure of an outboard engine during landing approach

A moving-base simulator investigation of the problems of recovery and landing of a STOL aircraft after failure of an outboard engine during final approach was made. The approaches were made at 75 knots along a 6 deg glide slope. The engine was failed at low altitude and the option to go around was not allowed. The aircraft was simulated with each of three control systems, and it had four high-bypass-ratio fan-jet engines exhausting against large triple-slotted wing flaps to produce additional lift. A virtual-image out-the-window television display of a simulated STOL airport was operating during part of the investigation. Also, a simple heads-up flight director display superimposed on the airport landing scene was used by the pilots to make some of the recoveries following an engine failure. The results of the study indicated that the variation in visual cues and/or motion cues had little effect on the outcome of a recovery, but they did have some effect on the pilot's response and control patterns

Some critical remarks on a new numerical method for simulation of dynamical systems

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68690/2/10.1177_003754976600600210.pd

THE NATURE OF DSS LITERATURE PRESENTED IN MAJOR IS CONFERENCE PROCEEDINGS (1980-1985)

This paper reports and analyzes the nature, content, and trends exhibited by DSS papers presented at the four major annual or biennial IS/DSS conferences during 1980-1985. (Three of the conferences held their first meeting during this period.) It then compares the findings from this analysis with those obtained with a different database, namely all DSS articles published in 22 professional journals during this same period. Inferences are drawn concerning (1) the perceived roles and benefits of conferences versus those of journals and (2) the apparent state and direction of the DSS field

Marketing Practices of Indiana Soybean Producers

Soybean marketing decisions play a critical role in maximizing farm income. The objective of the project described here was to identify market related educational needs and to provide benchmark information for producers. The assessment was conducted through a detailed direct-mail survey. The results of the survey demonstrate differences in market access among grower operation sizes and regions, and differences in forward pricing among grower operation sizes. Farmers with large operations generally have access to more markets and are more likely to manage price risk

Bioactivity and antimicrobial properties of chitosan-tobermorite membranes

Tobermorite (Ca5Si6O16(OH)2.4H2O) is a layered calcium silicate hydrate phase whose bioactivity and biocompatibility with respect to bone and dental tissues are documented. Chitosan is a biodegradable mucopolysaccharide derivative that has been evaluated as a tissue scaffold material for the in situ regeneration of bone and periodontal structures. Recent studies have shown that tobermorite-chitosan composites are potential candidates for use as biodegradable guided tissue regeneration (GTR) membranes [2,3]. During the GTR process, a membrane is used to isolate the exposed root surface from invasive epithelial and gingival tissues in order to enable the slow-growing periodontal ligament and hard tissues to regenerate. Resistance to potentially pathogenic oral bacteria is a highly desirable property of GTR membranes which are prone to biomaterial-centred infection. Silver (Ag+), copper (Cu2+) and gallium (Ga3+) ions are reported to confer antimicrobial activity when incorporated into bioactive materials [1,4,5]. In the present study, tobermorite was synthesised and ion-exchanged with Ag+, Cu2+ or Ga3+ ions. The in vitro bioactivity and antibacterial properties of solvent-cast tobermorite-chitosan composite membranes were then evaluated with respect to their potential use as GTR membranes to repair damaged periodontal structures

10. Effect of insecticide-treated bed nets on the dynamics of multiple Plasmodium falciparum infections

The rates of acquisition and loss of individual genotypes belonging to the FC27 family of the Plasmodium falciparum merozoite surface protein 2 (msp2) gene were studied in 120 children aged 5 months to 2·5 years, in a randomized controlled trial of insecticide-treated bed nets (ITNs) in Kiberege village, Tanzania. Analysis of longitudinal changes in positivity for individual alleles in samples collected at intervals of one month indicated that the average duration of infections, allowing for undetected parasite genotypes, was 73 d in those aged <18 months and 160 d in children aged ≥18 months, consistent with a shift from acute to chronic infection with age. Overall, 51% of genotypes infecting the host were estimated to be detected by polymerase chain reaction-restriction fragment length polymorphism analysis in any one sample of 0·5 μL of packed peripheral blood cells. In children less than 18 months old this sensitivity was 61% (SE = 6%) compared with 41% (SE = 6%) in older children. Conversely, the rate of appearance of new parasite genotypes was higher in children <18 months of age than in older children, but this partly reflected the difference in sensitivity. The overall incidence of new infections was estimated to be reduced by 17% in ITN users. There was no statistically significant difference between users and non-users in observed infection multiplicity, sensitivity, recovery rate, or estimated infection rates for individual alleles. This suggests that, in areas of high P. falciparum endemicity, ITNs have little effect on the establishment of chronic malaria infectio

The impact of professional development on general-education teachers' attitudes toward the inclusion of students with disabilities in the inclusive environment

Includes bibliographical references (pages [184]-191).The purpose of the study was (1) to identify the attitudes and concerns of general-education teachers responsible for the education of students with disabilities, and (2) to examine the extent to which professional development training influences general-education teachers’ attitudes toward inclusion. Quantitative data were collected using a pre/post-test consisting of 16 closed-ended test items while qualitative data were collected using open-ended survey questions and five openended semistructured interview questions that addressed the research questions investigated in this study. A mixed-method design was used to study 67 kindergarten through fifth-grade general-education teachers in three grade schools (K -l, 2-3, and 4-5) from a small suburban school district to assess their opinions and actions in their classroom settings regarding inclusion. Pretest data were analyzed using descriptive statistics (means and standard deviation) to assess teachers’ attitudes toward inclusion and best teaching practices prior to training. A posttest was conducted following the training to determine to what extent professional development training influences teachers’ attitudes and concerns. A paired /-test was used to compare the means of the two tests, and to test whether the differences between the means were statistically significant. The effect size was also calculated for each case school to summarize the overall effect of professional development experience. Following the posttest, 10 general-education teachers were interviewed for the purpose of determining their attitudes toward inclusion and to determine how their attitudes changed towards students with disabilities after training. The results of this study indicated that professional development had a moderate effect on teachers’ attitudes and that there is a need to provide ongoing professional development strategies to address the needs of general-education teachers, particularly pertaining to the integration of students with significant academic disabilities, or behavioral needs.Ed.D. (Doctor of Education