162 research outputs found
What Matters Most When Students and Teachers Use Interactive Whiteboards in Mathematics Classrooms?
As teachers, we are encouraged to immerse our students in rich and engaging learning environments (NSW Department of Education and Training, 2003). One teaching tool that can facilitate the creation of rich learning environments is the interactive whiteboard (IWB) (Baker, 2009). IWBs are quickly being introduced into schools across the nation and worldwide, and educators are exploring the implications of having them in the classroom. Of particular interest are student attitudes to the use of IWBs: what students think and feel about IWBs, and what factors matter most to students when IWBs are used in their classroom. Attitudes play an important part in student interest and engagement levels, therefore, it is important to determine current student attitudes towards IWB use in the classroom
The regulation of copper stress response genes in the Polychaete Nereis diversicolor during prolonged extreme copper contamination
Polychaetes are frequented in toxicological studies, one reason being that some members occupy shallow burrows in sediments and are maximally exposed to the contaminants that accumulate within them. We have been studying one population of the polychaete Nereis (Hediste) diversicolor exhibiting inheritable tolerance to extreme copper contamination in estuarine sediment. Using transcriptome sequencing data we have identified a suite of genes with putative roles in metal detoxification and tolerance, and measured their regulation. Copper tolerant individuals display significantly different gene expression profiles compared to animals from a nearby population living without remarkable copper levels. Gene transcripts encoding principle copper homeostasis proteins including membrane copper ion transporters, copper ion chaperones and putative metallothionein-like proteins were significantly more abundant in tolerant animals occupying contaminated sediment. In contrast, those encoding antioxidants and cellular repair pathways were unchanged. Nontolerant animals living in contaminated sediment showed no difference in copper homeostasis-related gene expression but did have significantly elevated levels of mRNAs encoding Glutathione Peroxidase enzymes. This study represents the first use of functional genomics to investigate the copper tolerance trait in this species and provides insight into the mechanism used by these individuals to survive and flourish in conditions which are lethal to their conspecifics
Assessing the Contribution of Mixed Farming Systems to Biodiversity across Australia\u27s Sheep‐Wheat Zone: The Grain & Graze Participatory Research Model
A Population-Based Serologic Survey of Immunity to Tetanus in the United States
Background. Vaccination rates are frequently considered a surrogate measure of protection. To provide more accurate estimates, serum levels of antibody against tetanus were measured as part of the third National Health and Nutrition Examination Survey (NHANES III), which studied a representative sample of the civilian, noninstitutionalized population of the United States.
Methods. We measured tetanus antitoxin using a solid- phase enzyme immunoassay in serum samples from 10,618 persons six years of age and older who were examined during phase 1 of NHANES III in 1988 to 1991.
Results. Overall, 69.7 percent of Americans six years of age and older had protective levels of tetanus antibodies (0.15 IU per milliliter). The rate decreased from 87.7 percent among those 6 to 11 years of age to 27.8 percent among those 70 years of age or older. Among children 6 to 16 years of age, 82.2 percent had protective levels of tetanus antibodies, with little variation according to race or ethnicity. More men than women were immune (79.0percent vs. 62.4 percent). Mexican Americans had a significantly lower rate of immunity (57.9 percent, P 0.05) than either non-Hispanic whites (72.7 percent) or non-Hispanic blacks (68.1 percent). Those with a history of military service, higher levels of education, or incomes above the poverty level were more likely to have protective antibody levels. Although the prevalence of immunity declined rapidly starting at the age of 40 years, most of the 107 cases of tetanus (with 20 deaths) reported in 1989 and 1990 occurred in persons 60 years of age or older.
Conclusions. Despite the fact that effective vaccines against tetanus have been available since the 1940s, many Americans do not have immunity to tetanus, and the rates are lowest among the elderly. There is an excellent correlation between vaccination rates (96 percent) and immunity (96 percent) among six-year-olds. However, antibody levels decline over time, and one fifth of older children (10 to 16 years of age) do not have protective antibody levels
An Alpine Malaise trap
The Southernmost region of Australia, the island of Tasmania, is also the most mountainous, with large areas of rugged alpine environments. This entomological frontier offers a distinct suite of insects for study including many endemic taxa. However, harsh weather, remote locations and rough terrain represent an environment too extreme for many existing insect trap designs. We report here on the design and efficacy of a new Alpine Malaise Trap (AMT), which can be readily hybridised with several other common insect trapping techniques. Advantages of the design include its light weight and portability, low cost, robustness, rapid deployment and long autonomous sampling period. The AMT was field tested in the Tasmanian highlands (AUST) in 2017. A total of 16 orders were collected. As expected, samples are dominated by Diptera. However, the trap also collected a range of flightless taxa including endemic and apterous species, Apteropanorpa tasmanica – closest relative of the boreal, snow scorpionflies (Boreidae). Combined and compared with other trap types the Alpine Malaise Traps captured less specimens but of a greater diversity than passive sticky traps, while drop traps captured less specimens but a greater diversity than AMT. The statistical potential of the catch is discussed
Local exome sequences facilitate imputation of less common variants and increase power of genome wide association studies
The analysis of less common variants in genome-wide association studies promises to elucidate complex trait genetics but is hampered by low power to reliably detect association. We show that addition of population-specific exome sequence data to global reference data allows more accurate imputation, particularly of less common SNPs (minor allele frequency 1–10%) in two very different European populations. The imputation improvement corresponds to an increase in effective sample size of 28–38%, for SNPs with a minor allele frequency in the range 1–3%
Male Circumcision for Prevention of HIV Transmission: What the New Data Mean for HIV Prevention in the United States
Recent clinical trials in Africa found that male circumcision reduces the risk of acquiring HIV from heterosexual sex--what are the implications of these studies for the United States
GeneDB--an annotation database for pathogens.
GeneDB (http://www.genedb.org) is a genome database for prokaryotic and eukaryotic pathogens and closely related organisms. The resource provides a portal to genome sequence and annotation data, which is primarily generated by the Pathogen Genomics group at the Wellcome Trust Sanger Institute. It combines data from completed and ongoing genome projects with curated annotation, which is readily accessible from a web based resource. The development of the database in recent years has focused on providing database-driven annotation tools and pipelines, as well as catering for increasingly frequent assembly updates. The website has been significantly redesigned to take advantage of current web technologies, and improve usability. The current release stores 41 data sets, of which 17 are manually curated and maintained by biologists, who review and incorporate data from the scientific literature, as well as other sources. GeneDB is primarily a production and annotation database for the genomes of predominantly pathogenic organisms
Measures of Autozygosity in Decline: Globalization, Urbanization, and Its Implications for Medical Genetics
This research investigates the influence of demographic factors on human genetic sub-structure. In our discovery cohort, we show significant demographic trends for decreasing autozygosity associated with population variation in chronological age. Autozygosity, the genomic signature of consanguinity, is identifiable on a genome-wide level as extended tracts of homozygosity. We identified an average of 28.6 tracts of extended homozygosity greater than 1 Mb in length in a representative population of 809 unrelated North Americans of European descent ranging in chronological age from 19–99 years old. These homozygous tracts made up a population average of 42 Mb of the genome corresponding to 1.6% of the entire genome, with each homozygous tract an average of 1.5 Mb in length. Runs of homozygosity are steadily decreasing in size and frequency as time progresses (linear regression, p<0.05). We also calculated inbreeding coefficients and showed a significant trend for population-wide increasing heterozygosity outside of linkage disequilibrium. We successfully replicated these associations in a demographically similar cohort comprised of a subgroup of 477 Baltimore Longitudinal Study of Aging participants. We also constructed statistical models showing predicted declining rates of autozygosity spanning the 20th century. These predictive models suggest a 14.0% decrease in the frequency of these runs of homozygosity and a 24.3% decrease in the percent of the genome in runs of homozygosity, as well as a 30.5% decrease in excess homozygosity based on the linkage pruned inbreeding coefficients. The trend for decreasing autozygosity due to panmixia and larger effective population sizes will likely affect the frequency of rare recessive genetic diseases in the future. Autozygosity has declined, and it seems it will continue doing so
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