17 research outputs found
International study of seventh grade students' understandings of scientific inquiry : the cases of Israel and South Africa
Although understanding of scientific inquiry (SI) is included in science education reform documents around the world, virtually nothing is known about middle school students' understandings of scientific inquiry. This is partially due to the lack of any valid assessment tool. However, a valid and reliable assessment has recently been developed and published. The Views About Scientific Inquiry [VASI]) (Lederman et. al., 2014). The purpose of this international project was to acquire the first baseline data on what middle school students know. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation
Mammography reporting at Tygerberg Hospital, Cape Town, South Africa
CITATION: Pitcher, R. et al. 2014. Mammography reporting at Tygerberg Hospital, Cape Town, South Africa. South African Medical Journal, 104:7, 456-457, doi:10.7196/SAMJ.8455.The original publication is available at http://www.samj.org.zaIn their recent article, Apffelstaedt et al.[1] analysed
16 105 mammograms performed at Tygerberg Hospital (TBH),
Cape Town, South Africa (SA), between 2003 and 2012. The
summary reported that âmammograms were read by experienced
breast surgeonsâ, while the discussion stated: âA further noteworthy
fact is that this TBH series was based exclusively on mammography
interpretation by surgeons with a special interest in breast health.â
The suggestion that mammograms were exclusively interpreted by
breast surgeons does not reflect the mammography workflow at our
institution.http://www.samj.org.za/index.php/samj/article/view/8455Publisher's versio
Understandings of scientific inquiry: an international collaborative investigation of seventh grade students
Although understandings of scientific inquiry (as opposed to conducting inquiry) is included in science
education reform documents around the world, little is known about what students have learned about inquiry
during their primary school years. This is partially due to the lack of any assessment instrument to measure
understandings about scientific inquiry. However, a valid and reliable assessment has recently been developed
and published, Views About Scientific Inquiry (VASI) (Lederman J. et. al., 2014). The purpose of this large
scale (i.e., 19 countries spanning six continents and including 2,960 students) international project was to get
the first baseline data on what grade students have learned. The participating countries were: Australia,
Brazil, Canada, Chile, China, Egypt, England, Finland, France, Germany, Israel, New Zealand, Nigeria, South
Africa, Spain, Sweden, United States, Taiwan, and Turkey. In many countries, science is not formally taught
until middle school, which is the rationale for choosing seventh grade students for this investigation. This
baseline data will simultaneously provide information on what, if anything, students learn about inquiry in
primary school, as well as their beginning knowledge as they enter secondary school
TRY plant trait database â enhanced coverage and open access
Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
International study of seventh grade students' understandings of scientific inquiry : the cases of Israel and South Africa
Although understanding of scientific inquiry (SI) is included in science education reform documents around the world, virtually nothing is known about middle school students' understandings of scientific inquiry. This is partially due to the lack of any valid assessment tool. However, a valid and reliable assessment has recently been developed and published. The Views About Scientific Inquiry [VASI]) (Lederman et. al., 2014). The purpose of this international project was to acquire the first baseline data on what middle school students know. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation
Deep observations of Kepler's SNR with H.E.S.S.
Keplerâs supernova remnant (SNR) which is produced by the most recent naked-eye supernova in our Galaxy is one of the best studied SNRs, but its gamma-ray detection has eluded us so far. Observations with modern imaging atmospheric Cherenkov telescopes (IACT) have enlarged the knowledge about nearby SNRs with ages younger than 500 years by establishing Cassiopeia A and Tychoâs SNRs as very high energy (VHE) gamma-ray sources and setting a lower limit on the distance to Keplerâs SNR. This SNR is significantly more distant than the other two and expected to be one of the faintest gamma-ray sources within reach of the IACT arrays of this generation. We report strong evidence for a VHE signal from Keplerâs SNR based on deep observations of the High Energy Stereoscopic System (H.E.S.S.) with an exposure of 152 hours, including 122 hours accumulated in 2017-2020. We further discuss implications of this result for cosmic-ray acceleration in young SNRs
Observation of burst activity from SGR1935+2154 associated to first galactic FRB with H.E.S.S.
Fast radio bursts (FRB) are enigmatic powerful single radio pulses with durations of several milliseconds and high brightness temperatures suggesting coherent emission mechanism. For the time being a number of extragalactic FRBs have been detected in the high-frequency radio band including repeating ones. The most plausible explanation for these phenomena is magnetar hyperflares. The first observational evidence of this scenario was obtained in April 2020 when an FRB was detected from the direction of the Galactic magnetar and soft gamma repeater SGR1935+2154. The FRB was preceded with a number of soft gamma-ray bursts observed by Swift-BAT satellite, which triggered the follow-up program of the H.E.S.S. imaging atmospheric Cherenkov telescopes (IACTs). H.E.S.S. has observed SGR1935+2154 over a 2 hour window few hours prior to the FRB detection by STARE2 and CHIME. The observations overlapped with other X-ray bursts from the magnetar detected by INTEGRAL and Swift-BAT, thus providing first observations of a magnetar in a flaring state in the very-high energy domain. We present the analysis of these observations, discuss the obtained results and prospects of the H.E.S.S. follow-up program for soft gamma repeaters and anomalous X-ray pulsars
Observation of burst activity from SGR1935+2154 associated to first galactic FRB with H.E.S.S.
Fast radio bursts (FRB) are enigmatic powerful single radio pulses with durations of several milliseconds and high brightness temperatures suggesting coherent emission mechanism. For the time being a number of extragalactic FRBs have been detected in the high-frequency radio band including repeating ones. The most plausible explanation for these phenomena is magnetar hyperflares. The first observational evidence of this scenario was obtained in April 2020 when an FRB was detected from the direction of the Galactic magnetar and soft gamma repeater SGR1935+2154. The FRB was preceded with a number of soft gamma-ray bursts observed by Swift-BAT satellite, which triggered the follow-up program of the H.E.S.S. imaging atmospheric Cherenkov telescopes (IACTs). H.E.S.S. has observed SGR1935+2154 over a 2 hour window few hours prior to the FRB detection by STARE2 and CHIME. The observations overlapped with other X-ray bursts from the magnetar detected by INTEGRAL and Swift-BAT, thus providing first observations of a magnetar in a flaring state in the very-high energy domain. We present the analysis of these observations, discuss the obtained results and prospects of the H.E.S.S. follow-up program for soft gamma repeaters and anomalous X-ray pulsars