30 research outputs found
Physical science workshop course for elementary teachers
Science for elementary school grades K-6 varies somewhat in content from one textbook series to another, but it is fairly common that 40-60% of the material covered is directly related to physics. These texts suggest that certain learning activities such as experiments, demonstrations, and observations be carried out by the teacher and the class. Often the apparatus for a learning activity is to be constructed from simple, readily available materials. The typical elementary school teacher has had little experience in performing experiments and is often frustrated in his/her attempts at carrying out the suggested learning activity. To meet this need we have developed a physical science workshop that is made available to teachers who are returning to the university for additional training
Wave demonstration device
Students often have difficulty gaining an understanding of wave motion without effective demonstrations being performed in the lecture. Many excellent approaches utilizing ripple tanks, waves on a spring, chain, rope, etc., are customarily employed. Perhaps the most well-known device for demonstrating many of the effects of wave motion is the shive or bell wave motion machine.1 The purpose of the present note is to describe a simple, inexpensive device which can be easily constructed by a teacher or student and can be used to demonstrate many of the properties of wave motion
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Ozone and aerosol distributions and air mass characteristics over the South Pacific during the burning season
In situ and laser remote measurements of gases and aerosols were made with airborne instrumentation to establish a baseline chemical signature of the atmosphere above the South Pacific Ocean during the NASA Global Tropospheric Experiment (GTE)/Pacific Exploratory MissionâTropics A (PEMâTropics A) conducted in AugustâOctober 1996. This paper discusses general characteristics of the air masses encountered during this experiment using an airborne lidar system for measurements of the largeâscale variations in ozone (O3) and aerosol distributions across the troposphere, calculated potential vorticity (PV) from the European Centre for MediumâRange Weather Forecasting (ECMWF), and in situ measurements for comprehensive air mass composition. Between 8°S and 52°S, biomass burning plumes containing elevated levels of O3, over 100 ppbv, were frequently encountered by the aircraft at altitudes ranging from 2 to 9 km. Air with elevated O3 was also observed remotely up to the tropopause, and these air masses were observed to have no enhanced aerosol loading. Frequently, these air masses had some enhanced PV associated with them, but not enough to explain the observed O3 levels. A relationship between PV and O3 was developed from cases of clearly defined O3 from stratospheric origin, and this relationship was used to estimate the stratospheric contribution to the air masses containing elevated O3 in the troposphere. The frequency of observation of the different air mass types and their average chemical composition is discussed in this paper
Sixteen diverse laboratory mouse reference genomes define strain-specific haplotypes and novel functional loci.
We report full-length draft de novo genome assemblies for 16 widely used inbred mouse strains and find extensive strain-specific haplotype variation. We identify and characterize 2,567 regions on the current mouse reference genome exhibiting the greatest sequence diversity. These regions are enriched for genes involved in pathogen defence and immunity and exhibit enrichment of transposable elements and signatures of recent retrotransposition events. Combinations of alleles and genes unique to an individual strain are commonly observed at these loci, reflecting distinct strain phenotypes. We used these genomes to improve the mouse reference genome, resulting in the completion of 10 new gene structures. Also, 62 new coding loci were added to the reference genome annotation. These genomes identified a large, previously unannotated, gene (Efcab3-like) encoding 5,874 amino acids. Mutant Efcab3-like mice display anomalies in multiple brain regions, suggesting a possible role for this gene in the regulation of brain development
Pricing Carbon Consumption: A Review of an Emerging Trend
Nearly every carbon price regulates the production of carbon emissions, typically at midstream points of compliance, such as a power plant. Over the last six years, however, policymakers in Australia, California, China, Japan, and Korea implemented carbon prices that regulate the consumption of carbon emissions, where points of compliance are farther downstream, such as distributors or final consumers. This article aims to describe the design of these prices on carbon consumption, understand and explain the motivations of policymakers who have implemented them, and identify insights for policymakers considering whether to price carbon consumption. We find a clear trend of policymakers layering prices on carbon consumption on top of prices on carbon production in an effort to improve economic efficiency by facilitating additional downstream abatement. In these cases, prices on carbon consumption are used to overcome a shortcoming in the price on carbon production: incomplete pass-through of the carbon price from producers to consumers. We also find that some policymakers implement prices on carbon in an effort to reduce emissions leakage or because large producers of carbon are not within jurisdiction. Since policymakers are starting to view prices on carbon consumption as a strategy to improve economic efficiency and reduce emissions leakage in a way that is compatible with local and international law, we expect jurisdictions will increasingly implement and rely upon them
Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.
BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden
Cutoff score of the sexual interest and desire inventory-female for diagnosis of hypoactive sexual desire disorder
To determine the most appropriate cutoff value for the Sexual Interest and Desire Inventory-Female (SIDI-F) score to discriminate between women with hypoactive sexual desire disorder (HSDD) and those with no female sexual dysfunction (FSD). The SIDI-F is a clinician-rated instrument consisting of 13 items designed to assess HSDD severity in women. The total score ranges from 0 to 51, with higher scores indicating better sexual function. Data from patients enrolled in a North American nontreatment study and a European nontreatment study were analyzed. Both studies were 4-week, prospective, multicenter trials designed to assess the reliability and validity of the SIDI-F. Only patients with HSDD or no FSD were included in this analysis. Receiver operating characteristics (ROC) analysis was used to determine the ability of the SIDI-F to differentiate between patients with HSDD and those with no FSD at baseline. A total of 428 women were included in this analysis: 174 from North America (HSDD 113, no FSD 61) and 254 from Europe (HSDD 130, no FSD 124). In the North American study, a SIDI-F cutoff score of 33 minimized the difference between sensitivity (94.7%) and specificity (93.4%). In the European study, SIDI-F cutoff scores of both 33 and 34 minimized the difference between sensitivity (95.2%) and specificity (94.4%). In appropriately screened women, a SIDI-F score of â€33 indicates the presence of HSD