548 research outputs found
Percentages as Part Whole Relationships
Five practising teachers in regional NSW implemented Teaching for Abstraction for the Year 6 topic âPercentagesâ. The authors constructed materials for a unit in which students explored familiar percentage contexts, searched for similarities in their mathematical structures and then applied their learnings to more abstract situations. Particular emphasis was given to additive versus multiplicative approaches in different percentage situations. After an introductory workshop, teachers taught the topic in eight 40 minute lessons. The results show that even though this approach is radically different from that to which students and teachers are accustomed, it has the potential to benefit student engagement, learning, and attitudes for both students and teachers. The overall conclusions have implications for how professional development for Teaching for Abstraction is addressed
Training and Development
Training and development are processes that lead to change in individual organizational members for the primary benefit of the organization. These processes are distinct from consulting, which helps decision makers arrive at those same goals. Training and development as well as consulting are functions for communication specialists. In this entry, the major dimensions are described. Needs assessment, technology and training, approaches to training, evaluation of training programs, and adult learning and professional development are addressed. Training as a career in organizational communication is described
Course-based Science Research Promotes Learning in Diverse Students at Diverse Institutions
Course-based research experiences (CREs) are powerful strategies for spreading learning and improving persistence for all students, both science majors and nonscience majors. Here we address the crucial components of CREs (context, discovery, ownership, iteration, communication, presentation) found across a broad range of such courses at a variety of academic institutions. We also address how the design of a CRE should vary according to the background of student participants; no single CRE format is perfect. We provide a framework for implementing CREs across multiple institutional types and several disciplines throughout the typical four years of undergraduate work, designed to a variety of student backgrounds. Our experiences implementing CREs also provide guidance on overcoming barriers to their implementation
La catåstrofe del barranco de Arås (Biescas, Pirineo Aragonés) y su contexto espacio-temporal
[ES] Se estudian las caracterĂsticas de la
precipitaciĂłn y del pico de crecida
durante la catĂĄstrofe ocurrida en el
barranco de ArĂĄs en la tarde del 7 de
agosto de 1996. Se ha podido comprobar
que aunque la tormenta fue muy
intensa en toda la cuenca, su violencia
alcanzó mayor magnitud en un pequeño
sector de la subcuenca de Betés, en
el que se ha estimado una intensidad
superior a 500 mm.hr-1 y una precipitaciĂłn
total algo superior a 250 mm.
En el tramo final del barranco de ArĂĄs
debieron registrarse unos 500 mÂłs-1
incluyendo los sedimentos transportados,
para una cuenca de 18.8 kmÂČ. Las
evaluaciones realizadas permiten estimar
que el 75 % del caudal procediĂł
de la subcuenca de Betés, que representa
sĂłlo el 28.7 % de la superficie
total de la cuenca. Se ha evaluado el
volumen de sedimentos movilizados
en el sector final del barranco de ArĂĄs.
Finalmente, el evento tormentoso ha
sido situado en un contexto espacial y
temporal mĂĄs amplio. La catĂĄstofe del
barranco de ArĂĄs confirma las limitaciones
de los actuales sistemas de anĂĄlisis
probabilĂstico de riesgos, dada su
gran irregularidad espacial y temporal.[EN] The characteristics of precipitation
and peak flow during the ArĂĄs catastrophe
in the evening of August, 7,
1996, are studied. The storm was very
intense over the whole basin, and
especially in a small area of the Betés
subbasin, in which intensities greater
than 500 mm.hr-1 have been estimated,
with a total amount of precipitation
somewhat higher than 250 mm. In
the final stretch of the ArĂĄs ravine a
discharge of 500 mÂłs-1, including the
sediments, have been estimated for a
basin of 18.8 kmÂČ.. Seventy five per
cent of the discharge carne from the
Betés subbasin, which represents only
28.7 per cent of the basin. The volume
of sediments mobilized in the final
stretch of the ArĂĄs ravine has also been
evaluated. Finally, the rainstorm event
has been placed in a larger spatial and
temporal context. The catastrophe of
the ArĂĄs ravine confirms the lirnitations
of existing systems of probabilistic
analysis, due to the spatial and temporal
irregularity of storm events.Peer reviewe
The Effect of iCook 4-H, a Childhood Obesity Prevention Program, on Blood Pressure and Quality of Life in Youth and Adults: A Randomized Control Trial
Objective: Obesity increases the risk of developing hypertension and from population-based samples with estimations that of 2-4% of the U.S. pediatric population has hypertension, which may affect quality of life. This study examined the effects of an obesity prevention program on blood pressure and quality of life in youth and adult participants. Methods: A multi-state research team recruited treatment dyads (youth and their adult meal preparer) to participate in a 12-week randomized control trial and follow-up through 24 months. The treatment group received a cooking and physical activity intervention, followed by booster sessions and mailed newsletters over the remaining two-year period. The control group received no intervention. Resting blood pressure and health related quality of life (HRQOL) surveys were administered at 0,4,12 and 24 months. Results: 228 dyads were recruited (n=77 control and n=151 for treatment). Youth and adult systolic blood pressure (SBP) increased over the 24 months (p=0.003 and p=0.03, respectively) with no differences between groups. From baseline to 24 months both control and treatment youthsâ physical and psychological HRQOL increased (p=0.01 and p=0.002, respectively). At 0 and 4 months, youth and adult SBP was positively correlated (r=0.24, p=0.003 and r=0.33, p\u3c0.001, respectively). In the treatment group, there was an inverse association between adult SBP and youth psychological HRQOL at 4 months (r=-0.20, p=0.04), and a similar trend in adult SBP and youth physical HRQOL at 4 months in the treatment group (r=-0.19, p=0.05). Conclusion: A youth-adult dyad obesity prevention program consisting of culinary, mealtime and physical activity education, elicited improvements in HRQOL in youth participants
Diagnosing Severe Falciparum Malaria in Parasitaemic African Children: A Prospective Evaluation of Plasma PfHRP2 Measurement.
In African children, distinguishing severe falciparum malaria from other severe febrile illnesses with coincidental Plasmodium falciparum parasitaemia is a major challenge. P. falciparum histidine-rich protein 2 (PfHRP2) is released by mature sequestered parasites and can be used to estimate the total parasite burden. We investigated the prognostic significance of plasma PfHRP2 and used it to estimate the malaria-attributable fraction in African children diagnosed with severe malaria. Admission plasma PfHRP2 was measured prospectively in African children (from Mozambique, The Gambia, Kenya, Tanzania, Uganda, Rwanda, and the Democratic Republic of the Congo) aged 1 month to 15 years with severe febrile illness and a positive P. falciparum lactate dehydrogenase (pLDH)-based rapid test in a clinical trial comparing parenteral artesunate versus quinine (the AQUAMAT trial, ISRCTN 50258054). In 3,826 severely ill children, Plasmadium falciparum PfHRP2 was higher in patients with coma (p = 0.0209), acidosis (p<0.0001), and severe anaemia (p<0.0001). Admission geometric mean (95%CI) plasma PfHRP2 was 1,611 (1,350-1,922) ng/mL in fatal cases (n = 381) versus 1,046 (991-1,104) ng/mL in survivors (n = 3,445, p<0.0001), without differences in parasitaemia as assessed by microscopy. There was a U-shaped association between log(10) plasma PfHRP2 and risk of death. Mortality increased 20% per log(10) increase in PfHRP2 above 174 ng/mL (adjusted odds ratio [AOR] 1.21, 95%CI 1.05-1.39, p = 0.009). A mechanistic model assuming a PfHRP2-independent risk of death in non-malaria illness closely fitted the observed data and showed malaria-attributable mortality less than 50% with plasma PfHRP2â€174 ng/mL. The odds ratio (OR) for death in artesunate versus quinine-treated patients was 0.61 (95%CI 0.44-0.83, p = 0.0018) in the highest PfHRP2 tertile, whereas there was no difference in the lowest tertile (OR 1.05; 95%CI 0.69-1.61; p = 0.82). A limitation of the study is that some conclusions are drawn from a mechanistic model, which is inherently dependent on certain assumptions. However, a sensitivity analysis of the model indicated that the results were robust to a plausible range of parameter estimates. Further studies are needed to validate our findings. Plasma PfHRP2 has prognostic significance in African children with severe falciparum malaria and provides a tool to stratify the risk of "true" severe malaria-attributable disease as opposed to other severe illnesses in parasitaemic African children
Housing Needs in Rural Communities
This study explored housing in small rural communities in an attempt to understand the available housing stock, perceptions of the need for housing, and perceived barriers to housing development. Data were collected through computer-assisted telephone interviews with key community informants. Interviews included forced-choice as well as open-ended questions. Housing issues are described through the words of community leaders with the goal of understanding communities\u27 needs and constraints. Lower cost housing for both renters and owners and housing options for elderly individuals continue to be areas of need in rural communities
Artemisinin resistance in Plasmodium falciparum malaria.
BACKGROUND: Artemisinin-based combination therapies are the recommended first-line treatments of falciparum malaria in all countries with endemic disease. There are recent concerns that the efficacy of such therapies has declined on the Thai-Cambodian border, historically a site of emerging antimalarial-drug resistance. METHODS: In two open-label, randomized trials, we compared the efficacies of two treatments for uncomplicated falciparum malaria in Pailin, western Cambodia, and Wang Pha, northwestern Thailand: oral artesunate given at a dose of 2 mg per kilogram of body weight per day, for 7 days, and artesunate given at a dose of 4 mg per kilogram per day, for 3 days, followed by mefloquine at two doses totaling 25 mg per kilogram. We assessed in vitro and in vivo Plasmodium falciparum susceptibility, artesunate pharmacokinetics, and molecular markers of resistance. RESULTS: We studied 40 patients in each of the two locations. The overall median parasite clearance times were 84 hours (interquartile range, 60 to 96) in Pailin and 48 hours (interquartile range, 36 to 66) in Wang Pha (P<0.001). Recrudescence confirmed by means of polymerase-chain-reaction assay occurred in 6 of 20 patients (30%) receiving artesunate monotherapy and 1 of 20 (5%) receiving artesunate-mefloquine therapy in Pailin, as compared with 2 of 20 (10%) and 1 of 20 (5%), respectively, in Wang Pha (P=0.31). These markedly different parasitologic responses were not explained by differences in age, artesunate or dihydroartemisinin pharmacokinetics, results of isotopic in vitro sensitivity tests, or putative molecular correlates of P. falciparum drug resistance (mutations or amplifications of the gene encoding a multidrug resistance protein [PfMDR1] or mutations in the gene encoding sarco-endoplasmic reticulum calcium ATPase6 [PfSERCA]). Adverse events were mild and did not differ significantly between the two treatment groups. CONCLUSIONS: P. falciparum has reduced in vivo susceptibility to artesunate in western Cambodia as compared with northwestern Thailand. Resistance is characterized by slow parasite clearance in vivo without corresponding reductions on conventional in vitro susceptibility testing. Containment measures are urgently needed. (ClinicalTrials.gov number, NCT00493363, and Current Controlled Trials number, ISRCTN64835265.
Dihydroartemisinin-piperaquine versus chloroquine to treat vivax malaria in Afghanistan: an open randomized, non-inferiority, trial
BACKGROUND: Afghanistan's national guidelines recommend chloroquine for the treatment of Plasmodium vivax infection, the parasite responsible for the majority of its malaria burden. Chloroquine resistance in P. vivax is emerging in Asia. Therapeutic responses across Afghanistan have not been evaluated in detail.
METHODS: Between July 2007 and February 2009, an open-label, randomized controlled trial of chloroquine and dihydroartemisinin-piperaquine in patients aged three months and over with slide-confirmed P. vivax mono-infections was conducted. Consistent with current national guidelines, primaquine was not administered. Subjects were followed up daily during the acute phase of illness (days 0-3) and weekly until day 56. The primary endpoint was the overall cumulative parasitological failure rate at day 56 after the start of treatment, with the hypothesis being that dihydroartemisinin-piperaquine was non-inferior compared to chloroquine (Delta = 5% difference in proportion of failures).
RESULTS: Of 2,182 individuals with positive blood films for P. vivax, 536 were enrolled in the trial. The day 28 cure rate was 100% in both treatment groups. Parasite clearance was more rapid with dihydroartemisinin-piperaquine than chloroquine. At day 56, there were more recurrent infections in the chloroquine arm (8.9%, 95% CI 6.0-13.1%) than the dihydroartemisinin-piperaquine arm (2.8%, 95% CI 1.4-5.8%), a difference in cumulative recurrence rate of 6.1% (2-sided 90%CI +2.6 to +9.7%). The log-rank test comparing the survival curves confirmed the superiority of dihydroartemisinin-piperaquine over chloroquine (p = 0.003). Multivariate analysis showed that a lower initial haemoglobin concentration was also independently associated with recurrence. Both regimens were well tolerated and no serious adverse events were reported.
CONCLUSIONS: Chloroquine remains an efficacious treatment for the treatment of vivax malaria in Afghanistan. In a setting where radical therapy cannot be administered, dihydroartemisinin-piperaquine provides additional benefit in terms of post-treatment prophylaxis, reducing the incidence of recurrence from 4-8 weeks after treatment
Estimation of gestational age from fundal height: a solution for resource-poor settings
Many women in resource-poor settings lack access to reliable gestational age assessment because they do not know their last menstrual period; there is no ultrasound (US) and methods of newborn gestational age dating are not practised by birth attendants. A bespoke multiple-measures model was developed to predict the expected date of delivery determined by US. The results are compared with both a linear and a nonlinear model. Prospectively collected early US and serial symphysis-pubis fundal height (SFH) data were used in the models. The data were collected from Karen and Burmese women attending antenatal care on the ThaiâBurmese border. The multiple-measures model performed best, resulting in a range of accuracy depending on the number of SFH measures recorded per mother (for example six SFH measurements resulted in a prediction accuracy of ±2 weeks). SFH remains the proxy for gestational age in much of the resource-poor world. While more accurate measures should be encouraged, we demonstrate that a formula that incorporates at least three SFH measures from an individual mother and the slopes between them provide a significant increase in the accuracy of prediction compared with the linear and nonlinear formulae also using multiple SFH measures
- âŠ