Predictors of Achievement When Virtual Manipulatives are Used for Mathematics Instruction

The purpose of this study was to determine variables that predict performance when virtual manipulatives are used for mathematics instruction. This study included the following quasi-experimental design features: 1) a large number of students (N=350); 2) within-class random-assignment to treatment groups; 3) retention effects measured by post-test and delayed post-test; 4) fidelity of instructional treatments documented through observations; and, 5) instrument development for the unit of study. This design was used to determine variables that predict student performance on tests of fraction knowledge for third- and fourth-grade students in two treatment groups: classroom instruction using texts and physical manipulatives (CI), and computer lab instruction using virtual fraction applets (VM). The Pre-test, Post-test 1, and Post-test 2 measured learning and retention of fraction concepts. Observation ethograms documented representation use. The results revealed that fewer demographic predictors of student performance (e.g., socio-economic status, English language learner status, and gender) exist during fraction instruction when virtual manipulatives were used. When instructors used virtual manipulatives, there was an equalizing effect on achievement in third and fourth grade classrooms, in that fewer demographic factors were influential for VM groups compared to CI groups

Predictors of Achievement When Virtual Manipulatives are Used for Mathematics Instruction

The purpose of this study was to determine variables that predict performance when virtual manipulatives are used for mathematics instruction. This study included the following quasi-experimental design features: 1) a large number of students (N=350); 2) within-class random-assignment to treatment groups; 3) retention effects measured by post-test and delayed post-test; 4) fidelity of instructional treatments documented through observations; and, 5) instrument development for the unit of study. This design was used to determine variables that predict student performance on tests of fraction knowledge for third- and fourth-grade students in two treatment groups: classroom instruction using texts and physical manipulatives (CI), and computer lab instruction using virtual fraction applets (VM). The Pre-test, Post-test 1, and Post-test 2 measured learning and retention of fraction concepts. Observation ethograms documented representation use. The results revealed that fewer demographic predictors of student performance (e.g., socio-economic status, English language learner status, and gender) exist during fraction instruction when virtual manipulatives were used. When instructors used virtual manipulatives, there was an equalizing effect on achievement in third and fourth grade classrooms, in that fewer demographic factors were influential for VM groups compared to CI groups

Identification of upper thermal thresholds during development in the endangered Nechako white sturgeon with management implications for a regulated river

Climate change-induced warming effects are already evident in river ecosystems, and projected increases in temperature will continue to amplify stress on fish communities. In addition, many rivers globally are impacted by dams, which have many negative effects on fishes by altering flow, blocking fish passage, and changing sediment composition. However, in some systems, dams present an opportunity to manage river temperature through regulated releases of cooler water. For example, there is a government mandate for Kenney dam operators in the Nechako river, British Columbia, Canada, to maintain river temperature <20°C in July and August to protect migrating sockeye salmon (Oncorhynchus nerka). However, there is another endangered fish species inhabiting the same river, Nechako white sturgeon (Acipenser transmontanus), and it is unclear if these current temperature regulations, or timing of the regulations, are suitable for spawning and developing sturgeon. In this study, we aimed to identify upper thermal thresholds in white sturgeon embryos and larvae to investigate if exposure to current river temperatures are playing a role in recruitment failure. We incubated embryos and yolk-sac larvae in three environmentally relevant temperatures (14, 18 and 21°C) throughout development to identify thermal thresholds across different levels of biological organization. Our results demonstrate upper thermal thresholds at 21°C across physiological measurements in embryo and yolk-sac larvae white sturgeon. Before hatch, both embryo survival and metabolic rate were reduced at 21°C. After hatch, sublethal consequences continued at 21°C because larval sturgeon had decreased thermal plasticity and a dampened transcriptional response during development. In recent years, the Nechako river has reached 21°C by the end of June, and at this temperature, a decrease in sturgeon performance is evident in most of the traits measured. As such, the thermal thresholds identified here suggest current temperature regulations may not be suitable for developing white sturgeon and future recruitment

Inhibition of HER2 enriches for Jagged1-dependent breast cancer stem cells: role for membrane Jagged1

Purpose: Human Epidermal Growth Factor Receptor 2 (HER2) positive breast cancer is driven by cells possessing stem-like properties of self-renewal and differentiation, referred to as Cancer Stem Cells (CSCs). CSCs are implicated in radiotherapy, chemotherapy resistance, and tumor recurrence. Notch promotes breast CSCs survival and self-renewal, and overexpression of Notch1 and the Notch ligand Jagged1 predict poor outcome. Resistance to anti-HER2 therapy in HER2+ breast cancer requires Notch1, and that combination of trastuzumab and a Gamma Secretase Inhibitor (GSI) prevents tumor relapse in xenograft models. Experimental Design: The current study investigates mechanisms by which HER2 tyrosine kinase activity regulates Notch-dependent CSC survival and tumor initiation. Results: Lapatinib-mediated HER2 inhibition shifts the population of HER2+ breast cancer cells from low membrane Jagged1 expressing to higher levels, independent of sensitivity to anti-HER2 treatment within the bulk cell population. This increase in membrane Jagged1 is associated with higher Notch receptor expression, activation, and enrichment of CSCs in vitro and in vivo. Importantly, lapatinib treatment results in growth arrest and cell death of Jagged1 low-expressing cells while the Jagged1 high-expressing cells continue to cycle. High membrane Jagged1 protein expression predicts poor overall cumulative survival in women with HER2+ breast cancer. Conclusions: These results indicate that higher membrane Jagged1 expression may be used to either predict response to anti-HER2 therapy or for detection of Notch sensitive CSCs post therapy. Sequential blockade of HER2 followed by Jagged1 or Notch could be more effective than simultaneous blockade to prevent drug resistance and tumor progression

Thermal Image Scanning for Influenza Border Screening: Results of an Airport Screening Study

Background: Infrared thermal image scanners (ITIS) appear an attractive option for the mass screening of travellers for influenza, but there are no published data on their performance in airports. Methods: ITIS was used to measure cutaneous temperature in 1275 airline travellers who had agreed to tympanic temperature measurement and respiratory sampling. The prediction by ITIS of tympanic temperature (37.8uC and 37.5uC) and of influenza infection was assessed using Receiver Operating Characteristic (ROC) curves and estimated sensitivity, specificity and positive predictive value (PPV). Findings: Using front of face ITIS for prediction of tympanic temperature $37.8uC, the area under the ROC curve was 0.86 (95$37.8uC at screening (95%CI 0 % to 12%); three had no influenza symptoms. Conclusion: ITIS performed moderately well in detecting fever but in this study, during a seasonal epidemic of predominantly influenza type B, the proportion of influenza-infected travellers who were febrile was low and ITIS were no

Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.

Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis

Safety in home care: A research protocol for studying medication management

<p>Abstract</p> <p>Background</p> <p>Patient safety is an ongoing global priority, with medication safety considered a prevalent, high-risk area of concern. Yet, we have little understanding of the supports and barriers to safe medication management in the Canadian home care environment. There is a clear need to engage the providers and recipients of care in studying and improving medication safety with collaborative approaches to exploring the nature and safety of medication management in home care.</p> <p>Methods</p> <p>A socio-ecological perspective on health and health systems drives our iterative qualitative study on medication safety with elderly home care clients, family members and other informal caregivers, and home care providers. As we purposively sample across four Canadian provinces: Alberta (AB), Ontario (ON), Quebec (QC) and Nova Scotia (NS), we will collect textual and visual data through home-based interviews, participant-led photo walkabouts of the home, and photo elicitation sessions at clients' kitchen tables. Using successive rounds of interpretive description and human factors engineering analyses, we will generate robust descriptions of managing medication at home within each provincial sample and across the four-province group. We will validate our initial interpretations through photo elicitation focus groups with home care providers in each province to develop a refined description of the phenomenon that can inform future decision-making, quality improvement efforts, and research.</p> <p>Discussion</p> <p>The application of interpretive and human factors lenses to the visual and textual data is expected to yield findings that advance our understanding of the issues, challenges, and risk-mitigating strategies related to medication safety in home care. The images are powerful knowledge translation tools for sharing what we learn with participants, decision makers, other healthcare audiences, and the public. In addition, participants engage in knowledge exchange throughout the study with the use of participatory data collection methods.</p